ML16054A418
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 code 1 ANSI B31.1, 1977 Edition through Summer 1978 Addenda Number 2 Ty pe 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
22 USAR 4.5MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 1 of 2SECTION 4REACTOR COOLANT SYSTEM I/djm4.5Reactor Coolant System Vents The reactor vessel at Monticello can be vented near the top via the safety/relief valves, 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 Monticello plant 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 all larger 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 the HPCI 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 discharge pipes which give an indication of a safety/relief valve being open or leaking. There is 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 steam pressure 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 steam supply 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 Control Room. Starting the HPCI turbine auxiliary oil pump will open the HPCI turbine stop valve 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:CNSTP Assoc Ref:
SR:2yrs N Freq: USAR-MANARMS:USAR-04.05Doc Type:Admin Initials:Date:
9703 Revision 22 USAR 4.5MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 2 of 2 I/djmpiping are seismically qualified, Class I. The HPCI steam supply and discharge lines and associated valves are seismically qualified, Class I. The RCIC steam supply 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 accepted when the plant was licensed.
The safety/relief valves, the HPCI system and the RCIC system all vent to the containment suppression pool, where discharged steam is condensed without causing a rapid containment pressure/temperature transient.
All the valves associated with the venting functions of the safety/relief valves, the HPCI 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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage1of5SECTION4REACTORCOOLANTSYSTEM I/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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage2of5 I/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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage3of5 I/arb4.6.2.3InstrumentationandControlInjectionofhydrogenandoxygeniscontrolledfromacontrolpanellocatedinthenortheastcorneroftheturbinebuildingonthe931ftelevation.Theamountofhydrogeninjectedmaybeautomaticallycontrolledbyplantload(mainsteam flow).Itisalsocontrollablebyamanualcontrolswitch.Thehydrogeninjection systemisautomaticallyshutdownwhenanyofthefollowingconditionsexist:
Ghighhydrogenflow Glowmainsteamflow Gareamonitorhighhydrogenconcentration Glowoxygenpressure Gautomaticterminationofrecombineroff-gasflow Glowoxygenconcentrationonoff-gas Gmanualtripfromcontrolroom Gmanualtripfromremotecontrolpanel GReactorSCRAMHydrogeninjectioninhibitsincludefeedwaterpumpnotrunning.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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage4of5 I/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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage5of5 I/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 REPORT Page 1 of 16SECTION 4REACTOR COOLANT SYSTEM I/cah FIGURES Figure 4.2-1 Reactor Vessel Outline and Nozzles Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 3 of 16 I/cahFigure 4.2-2 Core Spray Safe End Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 4 of 16 I/cahFigure 4.3-1 Reactor Coolant Recirculation System Isometric Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 5 of 16 I/cahFigure 4.3-2 Jet Pump Isometric Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 6 of 16 I/cahFigure 4.3-3 Jet Pump Efficiency versus Flow Rate Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 7 of 16 I/cahFigure 4.3-4 Jet Pump Characteristic Curve Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 8 of 16 I/cahFigure 4.3-5 Jet Pump Head Ratio versus Area Ratio Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 9 of 16 I/cahFigure 4.3-6 Jet Pump Flow Ratio versus Area Ratio Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 10 of 16 I/cahFigure 4.3-7 Typical Jet Pump Head Capacity Characteristics Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 11 of 16 I/cahFigure 4.3-8 Core Flow Measurement System SchematicPPPPPP LOWER PLENUM PRESSURE Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 12 of 16 I/cahFigure 4.3-9 NPSH Available by Subcooling at Pump Inlet versus NPSH at VariousTemperatures Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 13 of 16 I/cahFigure 4.4-2 Dual Relief/Safety Valve - Valve Closed Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 14 of 16 I/cahFigure 4.4-3 Dual Relief/Safety Valve - Valve Open Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 15 of 16 I/cahFigure 4.4-4 SRV Low-Low Set Solenoid Actuation Circuit for SRV "H"CLOSE ON SCRAM CLOSE ON PRESSUREINCREASE IN SRV DISCHARGE LINE REACTOR PRESS.
CLOSE > 1052 PSIG*
OPEN < 972 PSIG*
HS-S4H OPEN TDR 10 SEC TDR 10 SEC SEAL IN HS-S4HAUTOBLOCK SRV REOPENING FOR 10 SEC TDR TDRSEAL INSRV SOLENOID SV2-71H (ENERGIZE TO OPEN)* SETTINGS FOR SRV "H"NOTE: TYPICAL FOR DIVISION I SRVs "E", "G" & "H" Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 16 of 16 I/cahFigure 4.4-5 SRV Low-Low Set Solenoid Actuation Circuit for SRV "E"CLOSE ON SCRAM CLOSE ON PRESSUREINCREASE IN SRV DISCHARGE LINE REACTOR PRESS.
CLOSE > 1072*
OPEN < 992*
TD R 10 SEC TD R 10 SECSEAL INBLOCK SRV REOPENING FOR 10 SEC TD R TD RSEAL IN SOLENOID SV2-71J* SETTINGS FOR SRV "E" HS-S19 OPEN HS-S19AUTO LOW-LOW SET LOGIC BYPASSSRV DIV II TRANSFERRELAYNOTE: TYPICAL FOR DIVISION II SRVs "E", "G" & "H"SRV DIV II TRANSFER RELAY (C-253D)HS-S43 OPENSRV DIV II Local Control (C-253D)HS-S19A OPEN (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 code 1 ANSI B31.1, 1977 Edition through Summer 1978 Addenda Number 2 Ty pe 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
22 USAR 4.5MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 1 of 2SECTION 4REACTOR COOLANT SYSTEM I/djm4.5Reactor Coolant System Vents The reactor vessel at Monticello can be vented near the top via the safety/relief valves, 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 Monticello plant 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 all larger 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 the HPCI 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 discharge pipes which give an indication of a safety/relief valve being open or leaking. There is 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 steam pressure 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 steam supply 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 Control Room. Starting the HPCI turbine auxiliary oil pump will open the HPCI turbine stop valve 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:CNSTP Assoc Ref:
SR:2yrs N Freq: USAR-MANARMS:USAR-04.05Doc Type:Admin Initials:Date:
9703 Revision 22 USAR 4.5MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 2 of 2 I/djmpiping are seismically qualified, Class I. The HPCI steam supply and discharge lines and associated valves are seismically qualified, Class I. The RCIC steam supply 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 accepted when the plant was licensed.
The safety/relief valves, the HPCI system and the RCIC system all vent to the containment suppression pool, where discharged steam is condensed without causing a rapid containment pressure/temperature transient.
All the valves associated with the venting functions of the safety/relief valves, the HPCI 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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage1of5SECTION4REACTORCOOLANTSYSTEM I/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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage2of5 I/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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage3of5 I/arb4.6.2.3InstrumentationandControlInjectionofhydrogenandoxygeniscontrolledfromacontrolpanellocatedinthenortheastcorneroftheturbinebuildingonthe931ftelevation.Theamountofhydrogeninjectedmaybeautomaticallycontrolledbyplantload(mainsteam flow).Itisalsocontrollablebyamanualcontrolswitch.Thehydrogeninjection systemisautomaticallyshutdownwhenanyofthefollowingconditionsexist:
Ghighhydrogenflow Glowmainsteamflow Gareamonitorhighhydrogenconcentration Glowoxygenpressure Gautomaticterminationofrecombineroff-gasflow Glowoxygenconcentrationonoff-gas Gmanualtripfromcontrolroom Gmanualtripfromremotecontrolpanel GReactorSCRAMHydrogeninjectioninhibitsincludefeedwaterpumpnotrunning.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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage4of5 I/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-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage5of5 I/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 REPORT Page 1 of 16SECTION 4REACTOR COOLANT SYSTEM I/cah FIGURES Figure 4.2-1 Reactor Vessel Outline and Nozzles Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 3 of 16 I/cahFigure 4.2-2 Core Spray Safe End Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 4 of 16 I/cahFigure 4.3-1 Reactor Coolant Recirculation System Isometric Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 5 of 16 I/cahFigure 4.3-2 Jet Pump Isometric Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 6 of 16 I/cahFigure 4.3-3 Jet Pump Efficiency versus Flow Rate Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 7 of 16 I/cahFigure 4.3-4 Jet Pump Characteristic Curve Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 8 of 16 I/cahFigure 4.3-5 Jet Pump Head Ratio versus Area Ratio Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 9 of 16 I/cahFigure 4.3-6 Jet Pump Flow Ratio versus Area Ratio Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 10 of 16 I/cahFigure 4.3-7 Typical Jet Pump Head Capacity Characteristics Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 11 of 16 I/cahFigure 4.3-8 Core Flow Measurement System SchematicPPPPPP LOWER PLENUM PRESSURE Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 12 of 16 I/cahFigure 4.3-9 NPSH Available by Subcooling at Pump Inlet versus NPSH at VariousTemperatures Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 13 of 16 I/cahFigure 4.4-2 Dual Relief/Safety Valve - Valve Closed Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 14 of 16 I/cahFigure 4.4-3 Dual Relief/Safety Valve - Valve Open Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 15 of 16 I/cahFigure 4.4-4 SRV Low-Low Set Solenoid Actuation Circuit for SRV "H"CLOSE ON SCRAM CLOSE ON PRESSUREINCREASE IN SRV DISCHARGE LINE REACTOR PRESS.
CLOSE > 1052 PSIG*
OPEN < 972 PSIG*
HS-S4H OPEN TDR 10 SEC TDR 10 SEC SEAL IN HS-S4HAUTOBLOCK SRV REOPENING FOR 10 SEC TDR TDRSEAL INSRV SOLENOID SV2-71H (ENERGIZE TO OPEN)* SETTINGS FOR SRV "H"NOTE: TYPICAL FOR DIVISION I SRVs "E", "G" & "H" Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 16 of 16 I/cahFigure 4.4-5 SRV Low-Low Set Solenoid Actuation Circuit for SRV "E"CLOSE ON SCRAM CLOSE ON PRESSUREINCREASE IN SRV DISCHARGE LINE REACTOR PRESS.
CLOSE > 1072*
OPEN < 992*
TD R 10 SEC TD R 10 SECSEAL INBLOCK SRV REOPENING FOR 10 SEC TD R TD RSEAL IN SOLENOID SV2-71J* SETTINGS FOR SRV "E" HS-S19 OPEN HS-S19AUTO LOW-LOW SET LOGIC BYPASSSRV DIV II TRANSFERRELAYNOTE: TYPICAL FOR DIVISION II SRVs "E", "G" & "H"SRV DIV II TRANSFER RELAY (C-253D)HS-S43 OPENSRV DIV II Local Control (C-253D)HS-S19A OPEN (C-253D)01048864