ML20115J610

Forwards Rev 2 to EMF-91-168, Grand Gulf Unit 1 Cycle 6 Plant Transient Analysis & Rev 1 to EMF-91-169, Grand Gulf Unit 1 Cycle 6 Reload Analysis. Repts Submitted to Address Discrepancy in Procedure for Cycles 5 & 6 Failure Event

ML20115J610
Person / Time
Site:	Grand Gulf
Issue date:	10/26/1992
From:	Cottle W ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20115J613	List: ML20115J610 ML20115J614 ML20115J619
References
GNRO-92-00113, GNRO-92-113, NUDOCS 9210280269
Download: ML20115J610 (3)

Text

.a

e. :=:=:= ENTERGY October 26, 1992

w. Y. c onie, ti. S. Nuclea r Regulat ot y Comm iss ion linil Sint ion PI-137 Wash ingt on, D.C.

20555 Attentlon:

Doc utn e n t Cotitiol Desk Sub ject '

Grand Gulf Nurlent Statton Unit i

!)ock e t No.90-416 1.icense No. NPF-29 fondwnt er Cont r oller f a ilure Evotit Rentin 1 ys i s Re f erotums :

1.

l.e t t e r ftom W. T. Cott1e, Etit et gy Opern t lotis, I ric, to NRC,

" Cycle 5 Relond," June 8, 1990 ( AITM-90/0092) 2.

Letter from W. T. Cottlo, hntetgy Opetat.lons, I tic. to NRC,

" Cycle 6 Relond," December 5, lu91 (GNRO-91/00186)

GNRO-9?/00111 Gent lemen:

hntorgy Operntlons, luc. was I ereut ly not i f led b) Slemens Power Colporntlon (SPC) of n discrepancy in the procedoro u rl to anr y e t iv> Cycle 5 and i

cycle 6 l eedwnt er C<ntroller Unilure event (FWCF).

This in:lition was Iepoited utnler 10CFR Part ?! for the WNP-2 facil' s (h( en, No. NPP-1) v ia let t er rint ed August 6,

In9?.

Thin procedure

,a-first asr4 Int '

=

Cycle 5 nini wns used ngnin in t ha nnalyslu for Cycle 6.

SPC revet,t conclueled that the proceduto used in these GGNS FWCF nilysen in non-conservat ive relative to the benchmark cntos for t he SPC COTRANSA?

methodology, e,PC rennslyzed the IWCF event for CGNS nnd determined the blent i f ied non-conservat ism has no i tn pa c t on GGNS operntitis limits.

The COTRANSA2 code validntion is based on a comparison t o erspi r ical dat o Ior tnihine trip testing at the Peach 1:ottom Plant.

Ilow ev e r, the 1 WCl event in s1ight ly d ( f f ei ont from the bencl.ma rk case.

In 'hn FWCT event,

• be turbine t r ip ou.ui s above the norna l wa t e r level; wherens, in the bonchtna rk case, the trip e : curs at normal water level.

This di f fer ence, and thn associated difference in core p ress.ur i zat ion ra t e, conned the non-conservntive result s for 1he 1WCF nonlysit..

SPC established a rw orocedure which cor 'ct s the non-cotiservat ism atul provides conformance wi,h the nppioved hacin for the methodology.

The FWCr case wit h t he least mornin for GGNS Cycle 6 was then rennnlyzed using this I

new procedute.

Thn result s assore that the MCPR operating limit remains valid at thn most l im i t ing cond i t lon ( 102', Powe r/108%, Flow a t E00-30 EPPD and est ablishes a bonod ing incronse in event - ACPR t o ho applied t o results g ',\\ l r'

2 8 0 0'? ^27'/8NCrhR -

i 9210280269 921026 PDR ADOCK 05000416 p

PDR

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October 26, 1992 GNRO-92/00113 Page 2 of 4 for all other caans.

The rennnlysis reeulted in a mnx!.im luctenso of 0.014 in rWCF ACPR results for the limiting cond1 Lion which is conservatively rounded to 0.02 for all other canon. The results of tho tennalysis indicate that the FWCP is no more limiting than the bond Rojection No flypans t ransient at rated conditions.

These resulta have benn j

nynlunted in accordanco with the requirements of 10CTR50,59 and found to be l

accept able.

Although the Cycin 5 and Cycle 6 MCPR operating limits remnin valid, specific ACPR resulta reported in Attachmenta 4 and 5 of Rnforenco 1, and At tachments 6 and 7 of Referenco 2 do not reflect the result s obt alnod using the revised proceduro.

SN han revised t he GGNS current cyclo (Cycin 6) Rolond and Transient Annlysin Reports to include the chnnges in resulta nsmocinted with the revised FWCF proceduro. Theno updnted reports nro included an Attachmnnts 1 and 2.

Thn Cycle 5 Roland Report would bn updated as follows:

FWCENil vnluns in paragraph 5.1, page 15:

Do.1tn,CPR M C-2000 MWa/MTy mC FWCrNil 0,10 0.15 The Cycle 5 Transient Analysir; Report would bn updated at follown:

TWCFNil values in Tnbin 2.1, page 6:

Delta-CPR EOC-2000 mwd /MT,y E00 030 9X2 fl0 2X2 FWCFNil 0.09 0.10 0.15 0.15 Note: Corresponding data points in Figurn 2.1 and 2.2 would niso be updated.

Yours truly, I

t w:> F~' dae.a.;. -

WTC/WEL/nms l

nttachments: 1.

EMP-91-168 Revision 2, Grand Gulf Unit 1 Cycle 6 Plnnt Transient Analysis, September 1992 l-2.

EMF-91-169, Revision 1 Grand Gulf Unit 1 Cycin 6 Rolond Analysis, July 1992 i :

(Sco Next Pagn)-

09208271/SNhlCFIR - 2 l-l l

h October 26, 1992 GNRO-92/00113 Page 3 of 4 l

cc:

Mr. R.11. Detahard (w/n) i Hr. D. C. Illut r. (w/n)

Mr. R. B. McGehen (w/a)

Mr. N. S. Hoynolds (w/n) l' Hr.11. I.. Thomas (w/o)

- i Mr. Stewart D. Ebnet or (w/n) kegional Ariministrator U.S. Nuclear Regulatory Commission Region 11 101 Harletta St.

N.W., Sult a 2900 Atinnta, Georgin 30323 Mr. P. W. O'Connor, Project Manager (w/2) f Offico of Nucinar Reactor Regulation U.S. Nuclear Regulnt ory Cornmission Hall Stop 13113 Washington, D.C.

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