ML20237G933

Forwards Util to NRC Identifying Nonconservatisms in ECCS Discovered During Review of Design Basis.Revised Estimated Peak Clad Temp Below Limit of ECCS Acceptance Criteria.W/Certificate of Svc.Related Correspondence

ML20237G933
Person / Time
Site:	Turkey Point
Issue date:	08/21/1987
From:	Bauser M FLORIDA POWER & LIGHT CO., NEWMAN & HOLTZINGER
To:	Edles G, Gotchy R, Wilber H NRC ATOMIC SAFETY & LICENSING APPEAL PANEL (ASLAP)
References
CON-#387-4270 OLA-1, NUDOCS 8709030037
Download: ML20237G933 (6)

Text

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, $EIATED CORRESPA'DE m NEWMAN & HOLTZINGER, P.ge - pr-JACK R NEWMAN 1615 L ST R E ET, N.W. WiLUAM C bat R. JR JOMN E MOLTZiNGER JR DOUGL AS L BERE5rORD MelOL D F REIS WASHINGTON, D.C. 20036 JADE A E ATON NAUD8CE AKELRAD IP

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• JANETE B ECKER JA DOUst NIGMT. JR 3 ~) ,

LOf$ R FINRELST[lN*

PAut M mEc" GEORGE L EDG AR 2OR 955 6600 sRIAN R GISM JsLL E GRANT kATHLEEN M SME A ,.

ANDREW N GRC[NE*

DOUGL Ab G GREEN '

PAMEL A A L ACEV KAROL LYN NEWMAN .~ ~ ,

JOMN T STOUGM, JR FRANK R UNDM JAMES S VASILE KEVIN J LIPSON MICHAEL A BAUSER KATHLEEN M McDERMOTT ALVIN H GUTTERMAN JErrREY B MULMALL*

ED.ARDJ TWOMEv ERROL R PATTERSON JAME5 S WILCOA, JR August 21, 1987 s^~ci a'**

PAUL J EAviDG E

• REVIN P GALLEN JACOLYN A SiMMONS THOMAS A SCMMUT2 ROBERT H SOLOMON MiCMAEL F ME ALv ROBERT 4 WMiTg CHARLE5 C. THEBAUD. JR N ANCY A WMITE*

SCOTT A MARMAN ROBIN T. WIGGIN$*

STtA N P WRAnTZ -

DavlC B RA5mN

~ ROBERT LOWEN$T[iN DONALD J SILVERMAN HERBERT S COMN ERNE $T C SAYNARD,lif JOSEPM E STUBBS or covastL cov=sEL

• woT AD.sitTED *N O C Gary J. Edles, Chairman Howard A. Wilber Administrative Judge Administrative Judge Atomic Safety and Licensing Atomic Safety and Licensing Appeal Board Appeal Board U.S. Nuclear Regulatory U.S. Nuclear Regulatory 3 Commission Commission Washington, D.C. 20555 Washington, D.C. 20555 Dr. Reginald L. Gotchy Administrative Judge Atomic Safety and Licensing Appeal Board U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Re: In the Matter of Florida Power and Light Company (Turkey Point Plant, Unit Nos. 3 and 4) Docket Nos.

50-250 OLA-1, 50-251 OLA-1 m

Dear Administrative Judges:

Enclosed is a. copy of a letter dated August 20, 1987 f rom Florida Power arid Light Company ("FPL" or the " Company")

to the Nuclear Regulatory Commission Staff containing information concerning Emergency Core Cooling System ("ECCS") analysis for Turkey Point, Units 3 and 4.

As reported in the letter, and primarily as a result of a systematic review of the ECCS design basis for Turkey 8709030037 870821 PDR ADDCK 05000250 G PDR

Newx 4x & Hot.Tz1xozn. P. C.

Point initiated by the Company, FPL has discovered non-conservatism which have been estimated to result in a total )

increase in calculated peak clad temperature (PCT) of 56 F.

Adding 56*F to the previously calculated PCT of 2,051 F --

and allowing an additional 10 F for transition core effects to account for the presence of two types of fuel currently in the Turkey Point reactors (see generally, e.g., Florida ]

Power and Light Co. (Turkey Point Plant, Units 3 and 4), l LBP-87-21, 25 NRC - , slip op, at 3-11 (Jun. 23, 1987)) -- results j

' in an estimated PCT of 2,117 F. This is below the 2,200 F l l

limit contained in the ECCS acceptance criteria of 13 C.F.R.

S 50.46(b)(1). {

Sincerely, I

m i eE 4j Michael A. Bauser Enclosure MAB/ rap l

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__ --. - ~ _ . , _ _

t i

i AUGUST. 2 0 1987 I

l L-87-336 i U. S. Nuclear Regulatory Commission .

Attn: Document Control Desk j Washington, D. C. 20555  ;

Gentlemen: -

Re: Turkey Point Units 3 md 4 Docket Nos. 50-250 and 50-251 Lorge Break LOCA Analysis By letter L-85-157 dated April 16, 1985, Florido Power & Light Company (FPL) l reported a calculated peak clad temperature (PCT) of 2051 F in the event of a l worst case large break LOCA transient. The calculation was found acceptoble by l the NRC in a sofety evolvation issued on May 14, 1985. FPL has now completed its review of a recent Westinghouse evoluotion of subsequent PCT changes ,

resulting from non-conservatism identified during the Turkey Point Plant design l basis reconstitution effort. in accordance with 10 CFR 50, Appendix K,11.1, these l changes are hereby reported. I Westinghouse has informed FPL of m input error where three high-head safety l

injection pumps had been assumed in the analysis instead of two. The corrected i use of two pumps increased the PCT by 90 F to 2060 F. This change was reported to the NRC as Licensee Event Report (LER) 250-85-033.

While reviewing the design basis of the Emergency Core Cooling System (ECCS), o i non-conservatism in the assumed containment spray flow rate was discovered. I The analysis assumes a containment spray flow of 2900 gpm correspor: ding to a containment pressure of 60 psig. In octuality, the spray flow rate may increase to 3643 [g'pm while the containment pressure is nearly 0 psig in the beginning of the transient. This would cause additional heat removal from the containment, lower containment pressure, higher break flow md higher peak clad temperature. This non-conservatism was reported to the NRC os LER 250-87-14. Westinghouse has estiraated a PCT increase of 15 F to a total of 2075 F due to the increased containment spray flow.

TCC6/042/1 an FPL Group company

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i U. S. Nuclear Regulatory Commission )

L 336 .;

Page two )

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Another non-conservatism was discovered reioting to the low head safety injection <

pump flow rates assumed in the cecident analysis; a minimum of 3600 gpm during  !

the injection phase, and a maximum flow limit of 3750 gpm because of NPSH requirements during post-accident recirculation from the containment sump.

These current upper and lower flow rate limitations do not provide a large enough bond to allow the low head safety injection flow rote to be set with the required precision assuming the instrument inaccurocles associated with the instrumentation used to measure the pump flow. To broaden the band, the i minimum flow rate was reduced to 3400 gpm. This reduced analysis flow value l would result in on increase in PCT of 32 F, resulting in a revised PCT of 2107 F.

The revised PCT of 21070F for the worst case large -break LOCA transient correcting for the effects discussed herein is below the limit of 2200 F as per the i acceptance criteria in 10 CFR 50.46. FPL is evoluoting design changes to 1

mitigate the increases in PCT.

If there are any questions, please call us.

Very truly yours, W-.

C. O. Wo d Group V President Nuclear Energy l

COW /TCG/gp I i

cc: Dr. J. Nelson Croce, Regional Administrator, Region 11, USNRC  !

Mr. D. R. Brewer, USNRC Senior Resident inspector, Turkey Point Plant .

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TCG6/042/2

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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION *87 A,,

vo 24 R2 :06 )

BEFORE THE ATOMIC SAFETY AND LICENSING APPEAL BOARD I 20.

vou e

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In the Matter of ) Docket Nos. 50-250 OLA-1

) 50-251 OLA-1 FLORIDA POWER & LIGHT COMPANY )

) (Vessel Flux Reduction)

(Turkey Point Plant, )

Units 3 and 4) )

1 CERTIFICATE OF SERVICE I hereby certify that copies of the attached letter, dated August 21, 1987, to members of the Appeal Board from Michael A. Bauser and its Enclosure, were served on the following by deposit in the United States mail, first-class, postage prepaid and properly addressed, on the date shown below.

Dr. Robert M. Lazo, Chairman I l

Atomic Safety and Licensing Board Panel U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Dr. Emmeth A. Luebke Atomic Safety and Licensing Board Panel l U.S. Nuclear Regulatory Commission  !

Washington, D.C. 20555 Dr. Richard F. Cole Atomic Safety and Licensing Board Panel U.S. Nuclear Regulatory Commission Washington, DSC. 20555 Atomic Safety and Licensing Board Panel U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Secretary U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Attention: Chief, Docketing and Service Section (Original plus two copies)

Mitzi A. Young, Esq.

Office of Executive Legal Director U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Norman A. Coll, Esq.

Coll, Davidson, Cartdr, Smith, Salter 5 Barkett 3200 Miami Center 100 Chopin Plaza Miami, Florida 33131 Martin H. Hodder, Esq.

1131 N.E. 86th Street Miami, Florida 33138 Dated this 21st day of August, 1987.

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. H Michael A. Bauher' Newman & Holtzinger, P.C.

l 3615 L Street, N.W., Suite 1000 Washington, D.C. 20036 l

Telephone: (202) 955-6669 Attorneys for Florida Power & Light Company l

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