ML17258A570
| ML17258A570 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 08/05/1976 |
| From: | WHITE L D ROCHESTER GAS & ELECTRIC CORP. |
| To: | SCHWENCER A Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML17258A569 | List: |
| References | |
| NUDOCS 8202240227 | |
| Download: ML17258A570 (6) | |
Text
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~S9EA5TAVENUE,ROCHESTER.
N.,Y.>>~4~'~,AP'I~.August5,1976A.Schwencer, ChiefOperating ReactorsBranch41DivisionofOperating ReactorsOfficeofNuclearReactorRegulations U.S.NuclearRegulatory Commission Washington, D.C.20555
DearMr.Schwencer:
ThisletterisinresponsetoyourletterofJune24,1976,whichrequested additional information regarding ourproposedspentfuelpoolmodification.
Enclosedpleasefindtheresponses toyourquestions andtheresponses totheStaff'squestions re-sultingfromtheMay21,1976meetingbetweentheNRCStaffandRG&E.Verytrulyyours,LeonD.White,Jr.LDW/cernEnclosures 8202240227 82021'8PDRADOCN05000244P.PDRJ fp<>
Question15Theproposaltoincreasethestoragecapability ofthespentfuelstoragepoolfrom210fuelassemblies to595appearstochangethepossibleconsequences ifanobjectsuchasatornadomissileoi.droppedcraneloadimpactsonthestoredspentfuel.Providethefollowing additional information:
RESPONSE
(a)Whatconsideration hasbeengiventoreducingtheprobability orconsequences ofatornadomissileimpacting onstoredspentfuel?Theconsequences ofapostulated missileimpacting storedspentfuelintheproposedracks(595lo-cations)hasbeendecreased belowthatoftheexistingracks(210locations)'by preventing thefuelassemblies inthelatestdischarge batchfrombeingallgroupedtogether.
Thefissionproductdensityisgreatestinfuelassemblies thathavetheshortestcooldowntime,assumingsimilarirradiation.
Therefore, thestoredfissionproductdensitycanbereducedbysurrounding arecentlydischarge fuelassembly'withfuelassemblies thathavebeenstoredforayearormore.Figure15-1illustrates asectionoftheproposedspentfuelstoragerackswiththerecent.discharcre storedasillustrated.
There-mainingstoragelocations wereassumedtobefilledwithfuelassemblies thathavebeenoutofthereactorforoneyear(SeeFigure15-2).Thepossibleconsequences ofapostulated missileimpacting storedfuelwasevaluated bycomparing thesumofthefissionproductperunitofspentfuelpoolvolumedividedbytheMPCforthatnuclide,orxiMPC~iunitofspentfuelpoolvolumewhere:X.istheifissionproduct..th3.MPC.istheMaximumPermissive 3..thConcentration oftheifissionproduct(10CFR20)
.15-1 Question15(Continued)
Thisquantityweightsthefissionproductdensitysothatthenuclidesmostimportant indosecalculations aregivenmoreweight.Thisweighting represents amoremeaningful comparison thanifthecomparison weredoneonfissionproductdensityonly.Theabovequantitywascalculated fortheexistingspentfuelracksandtheproposedspentfuelrackswiththeloadingpatternillustrated onFigure15-2.Sincethisquantityislessfortheproposedrackandloadingpatternthanfortheexistingracks,theconsequences ofamissilewhichtransverses thesamespentfuelpoolvolumewillalsobelessthanfortheexistingpoolstructure.
15-2 Figure15-1ProposedSpentFuelRackWithRecentDischarge StoredAsXllustrated RecentDischarged FuelAssemblyWaterBoxEmptyFuelBox igure15-2OFOFOFOFOFOFOF'FRDF=RecentDischarged FuelOF=OldFuel