ML20154D521

Discusses Discovery of Addl Shop Weld in Recirculation Sys Loop a During Inservice Insp & IGSCC Mitigation Activities. Util Statements Re Performance of Stainless Steel Piping Weld Exams Conducted During 1984 Outage Require Correction

ML20154D521
Person / Time
Site:	Hatch
Issue date:	02/28/1986
From:	Gucwa L GEORGIA POWER CO.
To:	Muller D Office of Nuclear Reactor Regulation
References
2506N, SL-321, TAC-56540, TAC-60943, NUDOCS 8603060163
Download: ML20154D521 (3)

Text

.- - - - . - - . - ~ . . - --- .. . . .

% Georgia Power Cornpa,y c

333 Piedmont Avenue Atlanta, Georgia 30308 Teleptiore 404 526 6526

, Marting Address:

Post Off;ce Box 4545

! Atlanta. Georgra 30302

GeorgiaPower  ;

L T. Gucwa tre sautmvn entre system Manager Nuclear Safety and SL-321 Licensing Department 2506N -

1 February 28, 1986 i

i Director of Nuclear Reactor Regulation l

Attention: Mr. D. Muller, Project Director

! BWR Project Directorate No. 2 i Division of Boiling Water Reactor Licensing U. S. Nuclear Regulatory Commission 4 Washington, D. C. 20555

' NRC DOCKET 50-321 OPERATING LICENSE DPR-57 . ,

! EDW1N I. HATCH NUCLEAR PLANT UNIT 1 i PRESERVICE INSPECTION DISCREPANCIES Gentlemen:

j As previously discussed with the NRC, during the course of Hatch Unit 1

inservice inspection and IGSCC mitigation activities, plant personnel discovered an additional 28" diameter circumferential shop weld in the "A" -

Recirculation (Recirc) system loop. The subject shop weld is located

! between welds 1831-1RC-28A-5 and 1B31-1RC-28A-6 (Refer to Figure 1, attached) and has been designated as weld 1831-1RC-28A-5A (weld SA).

4 A detailed investigation conducted by Georgia Power Company (GPC)

personnel, including the Company's chief mechanical engineer, revealed that i weld 5A was shown only on the drawings of the piping fabricator, Associated Piping and Engineering Company (AP&E). The subject shop weld was not shown i on either the drawings of the NSSS vendor and Recirc piping supplier,

, General Electric, or the field erection drawings of the pi sing installer, i M. W. Kellogg. The original examination agency, Sout1 west Research i Institute (SwRI), did not include weld 5A and its adjacent longitudinal seam

piping welds 1B31-1RC-28A-5A-LU (weld SA-LU) and 1831-1RC-28A-5A-LD (weld 1

SA-LD) in the preservice inspection plan and the subsequent inservice

inspection plan which SwRI developed. Welds 5A, 5A-LU, and SA-LD were not

examined by SwRI during the preservice inspection of the Recirc piping in j December, 1973 Review of the AP&E documentation indicated that i nondestructive examinations were performed on weld 5A, including surface and volumetric examinations, which meet or exceed the requirements of the code l.

(i.e.,1971 Edition of ASE Section XI with Addenda through Summer 1972) to ,

j which the preservice inspection was conducted, j Welds M, 5A-LU, and 5A-LD were not inspected in service until the

current outage. Ultrasonic examination of the subject welds revealed that i' the welds were free of any rejectable indications. Subsequent to the .

ultrasonic examinations, weld 5A was treated using induction heating stress

' ,e l 8603060163 860228 '

I ADOCK 0 % y1 DR e g, y--- ,- ,9---,,,y-+---w---+,wy--g-y-.e-g----.---+--=-w-.-- -<------m, ---y---y--,-,,----.-v w--s-,-v, .w- ew- ---.,-vr------,,,-v.-- -w,--yw --w w -,,-.rwmve,yw,- ,,e,y, --ww-

l

g. 8 l

GeorgiaPower d l i

I Director of Nuclear Reactor Regulation ,

' Attention: Mr. D. Muller, Project Director BWR Project Directorate No. 2  :

February 28, 1986 l' Page Two improvement (IHSI). The weld was examined again post-IHSI and was found to 1 fully meet appropriate acceptance criteria, with no rejectable indications. -

1 It should be noted that insulation removal from this section of piping for ,

j normal or augmented inservice inspection had not been required since the  :

existence of the subject circumferential weld was unknown. The insulation 7 4

was removed during the current outage to facilitate mounting of equipment to '

perform IHSI on weld 1B31-1RC-28A-5 ,

Subsequent to the recent discovery, the ASME Code Class 1 stainless steel piping in the Rectre, Residual Heat Removal (RHR) and Reactor Water j Cleanup (RWCU) Systems for those sizes of piping required to be examined g pursuant to ASE Section XI Code requirements was walked down to assure t there were no additional welds. Two independent walkdowns indicated no additional welds exist in the aforementioned systems' piping. ,

i

As a result of the discovery of weld SA, statements made by GPC relative i

to the performance of stainless steel piping weld examinations conducted 1 1

during the 1984 maintenance / refueling outage require correction. Various  !

i GPC letters submitted to NRC relative to the 1984 outage and inspection '

+

plans for the 1985 outage have indicated that one hundred percent of the i piping welds (circumferential and branch connection welds) for those sizes i of Class 1 Recirc, RHR, and RWCU stainless steel piping required to be i examined pursuant to ASE Section XI were examined during the 1984 outage.

! As a result of the discovery of weld SA such statements were not accurate; approximately ninty nine percent of the accessible welds in the subject stainless steel piping were examined.

l Should you have any questions in this regard, please contact this office.

Sincerely yours, i

\ dWY M - m j L. T. Gucwa i

JAE/ab

Attachment

xc

Mr. J. T. Beckham, Jr.

Mr. H. C. Nix, Jr.

Dr. J. N. Grace (NRC-Region II) i Senior Resident Inspector 4

i j roons

---

._--,--_.__,,,..____.,..m_- -

--_.,___-,__..,m-__._ _ .-.~-_..m, _ , - . . . _ . _ _ - , - . , , , . , - -

N

]/ - ,

• RPV HlA **

eg2*AR-II 4- >

go lT Flo. B -l O S "' 8 - I(DISSIME.l AR M ET AL) 22*A M '

<: my 3LD-I F10. 8-l b F10. B-l6 4 LU-I 16 '

S- ~S(g (esnt s. %) SS A 124 81

.'- Ell- Rif R - 24 *- A-R ETURN 1: F10. 8- 2 l

- S(O 6A- < 14 BC-S -

84.g y H-85LU 14 9C-2 H A- 8 (s H(g-g ~

(44 HL l a 4)HA-2 a g r ,.,. " GR ATI NG (re At 1-2) SS A-2xzzz we 0R ATING

/g43c-I 10A 22 HL ON PUMP Q ll L D

• ,k il i2 -sa

= oiA. Es- .to _ #,5 9 *'of J /"'e N -i4 STANDARD 22-H 6- *

\ ) 0/ ' 14(U*O T-10 M ATERIAL SS / ,,

9 4 i

\-1 Te.  %"%

<o[ R'o<,,. ,,

'a b./>?\

r b eO o oo

,4 9 .

0.o l

GEORGI A POWER COMPANY EDWIN I. H ATCH NO. I Bil- RECIRC A-

• H AIN RECIRCUL ATION LOOP *A f/GVAE /

-