TENNEssEE VALLEY AUTHORITY O

CHATTANOOGA. TE10NESSE, 37401

Setemer 30v 19O3y

3DW50a.91/8261--R-i•o•botdegletiory Ceiissall mn.O'l m~tn

Region n Attn: W 8. Jaws?* O' lly,, Regimoa Administrator -101 *r16tta-Street, M9 Smit 2900Atana bo mvo an 30303lpom80;L ouhuLhI.H.•e1a

Dear Wb. Otleilly:

WAIT -Mi -aNOL KANT UNMIT 1 N 2 - P0SUVIATI) ACCIDM IMWW3-I OF -Ni TRM Mi STI 311D01 OR - UND-5D-390/62-1 11, UD-50-391/82-1011 FINAL 1T FOR IT M -MM MHIR M UDE Vl T 2

"The m~jt deficiency -s Lutlaly reprted to. C-O Inspetor U. alk'an October 15t 1012 4n accordance with 10 CPR 50.55(s) an NCR o M 21. Interls reports von admitted on Noveer 22v 1982 and Juneo23, 1963.ý_ llose Is- our final report for unit 1 and third Interim report f.r unt 2. Ve expect to subolt our net report for unit 2 oo -or about January 16, 1984.

I yohave anytquo S . pleasegotIn touch.ith 1. H. Shellat

- Very truly Yours

INUIDM I VLLEY AUIMNOI!

L. N. Hills, s oagr Nuclear Licensing

Imcosnure cc: We. Richard C. Delbungq Director (Enclosure)

Office of Inspection and Enforoement 13.3. Nuclear Regulatory Ccinission Vashlngton, D.C. 20555

Records Center (Enclosure) Institute of luolear Power Operations 1100 Circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339

OFFICIAL COPY

PDR

1983-TVA 50TH ANNIVERSARY

An Equal Opportunity Employer

lap

VATTS Dan-U~ POSTURATED A~CW UIS

10-01 1,313" 313ON? FOE UIT 1 lI

DesciptOn f Condition

"At*' -desi intent iSo omktat s•ch a manner as to adversely affee has been determined that the n0a00a steam generator Plos (at h m-amner an to cause the PORTs to sti or main feeduater line break. a stu blowdoun of mare than one stem ge -blowdoun of only one steam generato provided safety grade sition indt control room for the POls. Haweve action for 10 minutes.

PLANT VNITS -hAD 2 orF "=N! IHA 00 STUNGRAO

S50o55(ge) -TUiliD IN'T'RIM UPmON? IONt t131? 2

asmaty grade equipmnt wM not fail in t the safe operatoas of the plant. It sty grade automatic Control loop for the relief valves) could fail in s9h a at open. During a postulated main steam k open PN could cuse uncontrolled

erator (the ISMAR assumes accident r). It should be noted that TWA has eation and manual override in the main r, TVAs analysis assumes no operator

Safety Implications

If the unoontrolled bloudown of two steam generators was due to a c faedvater line break on S3-1 and a failed open PORT on S3-0, the turbine, driven pump may not be available after 10 minutes. The analysis assumes that motor-driven pump A is-available and motordriven pump 9 failed to start due to single failure. The availability of pump-A is assured by isolating the pump from the faulted steam generator In accordance with the emergency operating instructions. If the turbine driven pump and motor driven pump B are not available, the best removal capability of the Auxiliary Feeduater Systems could be degraded below its design basis. Consequently,. the ability of the affected system to safely shutdown the reactor 'ay be degraded.

Corrective Action o- Unit I

TWA will disposition the nonoonformance by rearranging the power supplies to the stem generator PORT remote mnual control circuits. The rearranging of the power supplies vill ensure that the design basis for the auxiliary feedwter system Including the effects due to single failure will not be violated by any design basis event.

Engineering change respectively) have Design work on OCR November 15, 1983. should be complete

notices (ECis) 3924 and 3925 (units 1 and 2, been Issued to implement the design changes. an IM 8211 under ECV 3924 should be complete by COS rework associated with the design revisions

by February 1, 1q84, for unit 1.

Interim ProreHs on Unit 2

TVA will provide the next report on unit 2 upon completion of the design work associated with this NCR under ECN 3925.

XOS6"