ML20084N446

Interim Deficiency Rept 83-05 Re Preservice Insp Weld Indications.Initially Reported on 830429.Disposition of Weld Indications to Be Finalized within 90 Days of Completion of Hot Functional Testing Scheduled for 830801

ML20084N446
Person / Time
Site:	Byron
Issue date:	05/26/1983
From:	Swartz E COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
10CFR-050.55E, 10CFR-50.55E, 10CFR-505-55E, 6656N, 83-05, 83-5, NUDOCS 8306030225
Download: ML20084N446 (3)

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x Commonwrith Edison C ) one First National Plaza, Chicago, Ilhnois 6 C' - Address Reply to: Post diEe Box 767  !

] Chicago. tilinois 60690 f

May 26, 1983 i

Mr. James G. Keppler, Regional Administrator Directorate of Inspection and i

Enforcement - Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road j Glen Ellyn, IL 60137 i

Subject:

Byron Station Unit 1 10 CFR 50.55(e) 30 Day Report Preservice Inspection Weld Indications NRC Docket No. 50-454-References (a): E. D. Swartz letter to H. R. Denton 1 dated Marchf23, 1983.

(b): 'D. L. Farrar letter to J. G. Keppler dated May 16, 1983.

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Dear Mr. Keppler:

On April 29, 1983, the Commonwealth Edison Company Project

Engineering Department notified Mr. Julian M. Hinds of your office of a l deficiency reportable pursuant to 10 CFR 50.55(e) regarding weld indica-d tions identified during the Unit-1 Preservice Inspection at Byron Station.

For your tract:ing purposes, this deficiency was assigned Number 83-05.

This letter fulfills the thirty (30) day reporting requirements of 10 CFR 50.55(e) regarding this matter and is considered to be an interim report, i

DESCRIPTION OF DEFICIENCY

, The preservice nondestructive examination under ASME Section XI 1977 i Edition, with addenda through the Summer 1978 Addenda, has resulted in seven (7) rejectable indications in weld seams on Steam Generators #1 and

1. 2, and the Pressurizer o f Byron Unit 1. On Steam Generator #1, two (2) indications are located in weld seam SGC-03, which is the third circumferential weld from the bottom of the steam generator. On Steam bu Generator #2, three (3) indications are located on weld seam SGC-06, the l circumferential~ weld between the transition cone and the upper shell. On i the Pressurizer, two (2) indications are located on weld seam PC-01, the i circumferential weld between the shell and the bottom head.

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J. G. Keppl~er. -

2- May 26, 1983 ANALYSIS'0F SAFETY IMPLICATIONS A

Stresses ~due to system pressure and repeated heat-ups and cooldowns 4 have the potential for causing. Code. rejectable weld indications to t -propagate into-through-wall cracks. There is a possibility that such F propagation'migh,t occur'before it could be detected by nondestructive testing.duringjthe(first inservice inspection interval.

'For1the indicat' ions in the Pressurizer, a-th' rough-wall crack would result-in Reacto;r' Coolant System (RCS) leakage.- In such an event, the

, loss > of, RCS inventory is expected to be small and.would .be detected by the various available Reactor Coolant Inventory Monitoring. Systems. A detailed description of these monitoring systems can be! found in Section 5.2.5 of the Byron FSAR as recently revised and documented in References (a) and.(b). -

For the indications in'the. Steam Ge"nerato'rs, a through-wall crack-would result in a secondary system.steamuleak. If such a leak occurred,

'the leak would:be expected to be small and it would be detected by a change in the containment environmental parameters as well as a change in the containment-sump inventory.

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I I In both case's of weld indication propagation, the.resultantEl'eaks are expected tolbe promptly detected in-order.to prevent anyLadverse safety consequences. ,/ ,

CORRECTIVEiACTION I :The seven'(7) weld indications-were originally identified by the .

preservice11nspection contractor. After.the' examination-data was analyzed by Westinghouse; re-examinations of the indications were performed to verifythe}accuracyofstheoriginaldata.. The results are asifollows:

A. ' Steam Generator #1 - On'e indication is rejectable and one indication v" is marginally rejectable. based on Section~XI calculations. Both indications will be removedk' l- 'B. Steam' Generator #2 - Re-examinationsswere prevented by insulation-L -rings needed for hot-functional? testing. The re-examinations will be b ,e performed af ter _- the completion o f . hot - functional ' testing. 'The-

, acceptablility of' the three indications will be determined :from the results/off these examinations.

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C. Pressurizer - Re-examination 'of the two (2) indications were y perforned, however, 'the' accuracy of the data . is 'somewhat suspect due itofthe(complex entry surface-geometry. Conclusions on' acceptability-r -areicontingent on further analysis' of geometrical configurations of

[_ . sweld area after hot functional.. testing. -

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J. G. Keppler May 26, 1983 Hot-functional testing is expected to be completed by August 1, 1983. The disposition of all weld indications should be finalized within ninety (90) days following this date and a - final report will be provided at that time. All required repairs will be made prior to final fuel load.

Please address any gestions that you or your staff may have concerning this matter to this office.

Very truly yours, E. Douglas Swartz Nuclear Licensing Administrator 1m-cc: Region III Inspector - Byron Director of Insp. and Enf.

US Nuclear Regulatory. Commission Washington, D.C. 20555 i

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- 6656N-i._

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