ML18008A038

Forwards Acceptance Criteria for ECCS in Light Water Nuclear Power Reactors for Period 891017-901026

ML18008A038
Person / Time
Site:	Turkey Point
Issue date:	12/20/1990
From:	Plunkett T FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
L-90-434, NUDOCS 9101030099
Download: ML18008A038 (8)

Text

ACCELERATED DIST UTION DEMONSTRATION SYSTEM l.

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR: 9101030099 DOC. DATE: 90/12/20 NOTARIZED: NO DOCKET g FACIL:50-250 Turkey Point Plant, Unit 3, Florida Power and Light C 05000250 50-251 Turkey Point Plant, Unit 4, Florida Power and Light C 05000251 AUTH. NAME AUTHOR AFFILIATION PLUNKETT,T.F. Florida Power & Light Co.

RECIP.NAME RECIPIENT AFFILIATION R Document Control Branch (Document Control Desk)

SUWECT: Forwards acceptance criteria for ECCS in light water nuclear power reactors for period 891017-901026. D DISTRIBUTION CODE: A001D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: OR Submittal: General Distribution NOTES RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-2 LA 1 1 PD2-2 PD 1 1 D AULUCK,R 2 2 D

INTERNAL: NRR/DET/ECMB 9H 1 1 NRR/DET/ESGB 1 1 NRR/DOEA/OTSB11 1 1 NRR/DST 8E2 1 1 S NRR/DST/SELB 8D 1 1 NRR/DST/SICB 7E 1 1 NRR/DST/SRXB 8E 1 1 NUDOCS-ABSTRACT 1 1 OC 1 0 OGC/HDS2 1 0 G FILE 01 1 1 RES/DSIR/EIB 1 1 EXTERNAL: NRC PDR 1 1 NSIC 1 1 D

D D

NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE iVASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 18 ENCL 16

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P.O. Box 029100, Miami, FL, 33102-9100 DEC RO 1980 L-90-434 10 CFR 50.46 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Re: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling Systems In Light Water Nuclear Power Reactors" Annual Re ort Gentlemen:

10 CFR 50.46(a) (3)(ii) requires that licensees report to the Commission at least annually the nature of changes to or errors discovered in the emergency core cooling system (ECCS) evaluation models, or in the application of such models, that affect the peak clad temperature calculation, and their effect on the limiting ECCS analysis. Florida Power and Light Company's report for Turkey Point Units 3 and 4 for the period October 17, 1989 through October 26, 1990 is attached.

Should there be any questions, please contact us.

Very truly yours, 7,

T~

f plcclvkE~ k/

F. Plunkett Vice President Turkey Point Plant Nuclear Attachment TFP/RJT/rjt cc: Stewart D. Ebneter, Regional Administrator, Region Il, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant

,A 9iOi030099'0i220 05000250 PDR ADOCK R PDR an FPL Group company

L-90-434 Attachment Page 1 ATTACHMENT Re: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling Systems In Light Water Nuclear Power Reactors" Annual Re ort By letter L-89-422 dated December 20, 1989, Florida Power and Light Company (FPL) reported a peak clad temperature of 2144'F in the event of a worst case large break LOCA (LBLOCA) transient. This value included a calculated temperature of 2051'F plus 93'F increment due to reduced safety injection flow, increased containment spray flow, transition fuel core penalty, containment purge coincident with a LBLOCAg and increased steady-state pressurizer pressure uncertainty band.

Recent plant changes and corrections in LBLOCA coding have resulted in a further increase in the peak clad temperature for the worst case large break LOCA of 27'F for a total of 2171'F. This includes a 25'F increase due to LOCTA coding errors and a 2'F increase due to the insertion of stainless steel rods in reconstituted fuel assemblies .

By letter L-89-422, Florida Power and Light Company reported a peak clad temperature of 1989'F in the event of a worst case small break LOCA (SBLOCA) transient. This value included a calculated temperature of 1605'F plus 384'F increment increase due to delayed AFW Enthalpy Switchover, AFW initiation delay time, open blowdown sample lines, thimble plugs removal, increase in allowed containment temperature, increase in steady-state pressurizer uncertainty and transition core penalty.

Recent plant changes and corrections in SBLOCA coding have resulted in a further increase in the peak clad temperature for the worst case small break LOCA of 71'F for a total of 2060'F. This includes a 25'F increase due to SBLOCTA coding errors, 40 F increase due to a reduced fuel rod gap pressure, 4'F increase due to K(z) discrepancy, and a 2'F increase due to the insertion of stainless steel rods in reconstituted fuel assemblies.

The large break LOCA analysis as described in the FSAR was performed by Westinghouse in 1983 using the BART computer model without spacer grids.

The small break LOCA analysis as described in the FSAR was performed by Westinghouse in 1983 using the WFLASH computer code.

L-90-434 Attachment Page 2 The revised peak clad temperatures of 2171'F for the worst case large break LOCA and 2060'F for the worst case small break LOCA correcting for the effects discussed herein and summarized in Tables 1 and 2 (enclosed) are below the limit of 2200'F as per the acceptance criteria in 10 CFR 50.46.

Westinghouse continues to work to resolve the generic issues related to their LOCA models. Issues which may impact Turkey Point's large break LOCA analyses are: (1) the top skewed axial power shapes, and (2) steam generator tube damage due to combined seismic and LOCA loads. Scoping analyses performed by Westinghouse have shown that the use of spacer grids in the BART model would provide enough PCT reduction to cover potential penalties caused by the above effects.

L-O0-434 Attachment Page 3 TABLE 1 TURKEY POINT UNITS 3 AND 4 PREDICTED PEAK CLAD TEMPERATURES CURRENT LBLOCA EVALUATIONS THAT HAVE ASSESSED PCT PENALTIES Analysis of Record Evaluations s ecified in L-89-422 3 HHSI TO 2 HHSI Pumps O' Increased Containment Spray Flow 15 F Reduced LHSI/RHR Flow 32'F Effect of Containment Purging O' Implementation of Debris Resistant FA 3F Pressurizer Pressure Uncertainty 8'F Transition Core Penalty 10 F Further Reduced RHR Flow 7 F Total LBLOCA PCT specified in L-89-422 Evaluations since issuance of L-89-422 LOCTA Coding Errors 25oF Stainless Steel Rods Cycle 12 Fuel 2 F Total Estimated LBLOCA PCT

0 L-90-434 Attachment Page 4 TABLE 2 TURKEY POINT UNITS 3 AND 4 PREDICTED PEAK CLAD TEMPERATURES CURRENT SBLOCA EVALUATIONS THAT HAVE ASSESSED PCT PENALTIES Analysis of Record 1605F Evaluation s ecified in L-89-422 Open Blowdown Sample Lines 19F Thimble Plug Removal 21'1'F Increase in Allowed Containment Temperature Pressurizer Pressure Uncertainty 13 F Implementation of Debris Resistant FA 27'F Delayed AFW Enthalpy Switchover 223'F Increase in AFW Initiation Delay Time 50 F Total SBLOCA PCT specified in L-89-422 198 9F Evaluations since issuance of L-89-422 SBLOCTA Coding Errors 25 F Reduced Reload Gap Pressure 4 O' Stainless Steel Rods Cycle 12 Fuel 2 F Power Increase Due to K(z) Discrepancy 4 F Total Estimated SBLOCA PCT 2060'V