ML17284A659

Provides Requested 30 Day Rept Re Insp of Reactor Core Shroud Welds for Indications of Stress Corrosion Cracking. Shroud Insp Requested by 940725 Ltr Has Been Completed

ML17284A659
Person / Time
Site:	Columbia
Issue date:	06/18/1998
From:	Webring R WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-94-03, GL-94-3, GO2-98-101, NUDOCS 9806240265
Download: ML17284A659 (8)

Text

~ CATEGORY 1 REGULATORY INFORMATION DISTRIBUTIOh YSTEM (RIDS)

ACCESSION NBR:9806240265 DOC.DATE: 98/06/18 NOTARIZED: YES DOCKET FACIL:50-397 WPPSS Nuclear Project, Unit 2, Washington Public Powe 05000397 AUTH. NAME AUTHOR AFFILIATION WEBRING,R.L,. Washington Public Power Supply System RECIP.DAME 'ECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Provides requested 30 day rept re insp of reactor core shroud welds for indications of stress corrosion cracking.

DISTRXBUTION CODE: A018D COPIES RECEIVED:LTR ENCL SIZE:

TXTLE: GL 94-03 Intergranular Stress Corrosion Cracking of Core S rouds in B NOTES:

T RECIPIENT E RECIPIENT COPIES COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL POSLUSNY,C 1 1 INTERNA '.ILE CEN E 1 1 1 NRR/DE/EMCB 1 1 NRR DE/EMEB 1 1 NRR/DSSA/SRZB 1 1 RES/DET/EMMEB 1 1 EXTERNAL: NRC PDR D

N NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD) ON EXTENSION 415-2083 TOTAL NUMBER OF COPIES REQUIRED: LTTR 7 ENCL 7

WASHINGTON PUBLIC POWER SUPPLY SYSTEM P.O. Box 968 ~ Richland, Washington 99352-0968 I~A )

June 18,1998 G02-98-101 Docket No. 50-397 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Gentlemen:

Subject:

WNP-2, OPERATING LICENSE NPF-21, 30-DAY REPORT OF INSPECTION RESULTS, GENERIC LETTER 94-03, "INTERGRANULARSTRESS CORROSION CRACKING OF CORE SHROUDS"

References:

1) NRC Generic Letter 94-03, dated July 25, 1994, "Intergranular Stress Corrosion Cracking of Core Shrouds in Boiling Water Reactors"

2) Letter GO2-96-010, dated January 15, 1996, JV Parrish (SS) to NRC, "Amendment to Generic Letter 94-03 Response"

3) Letter GO2-98-010, dated January 16, 1998, JV Parrish (SS) to NRC, "Amended Response to Generic Letter 94-03"

4) Letter GO2-98-090, dated May 22, 1998, PR Bemis (SS) to NRC, "Clarification of Amended Response to Generic Letter 94-03"

5) BWR Vessel and Internals Project (BWRVIP) Document BWRVIP-01, "BWR Core Shroud Inspection and Flaw Evaluation Guideline,"

Revision 2

6) Letter dated December 10, 1997, Carl Terry (BWROG) to NRC, "Change to Category B Core Shroud Inspection Recommendations" In Reference 1 the Staff requested that the Supply System perform an inspection of reactor core shroud welds for indications of stress corrosion cracking, and report the results of the inspection within 30 days from completion. In Reference 2 the Supply System informed the Staff that core shroud inspection would be completed during the Spring 1998 refueling outage.

References 3 and 4 provided the Staff information regarding the intended scope and methodology to be used for the inspection. The purpose of this letter is to provide the requested 30 day report and inform the Staff that the shroud inspection requested by Reference 1 has been completed.

9806240265 9'80618

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., 30-DAY REPORT OF INSPECTION RESULTS, GL 94-03, "INTERGRANULAR STRFSS CORROSION CRACKING OF CORE SHROUDS" In aCcordarice with References 5 and 6, the Supply System has completed a category B, limited core shroud weld inspection of the four core shroud representative areas. The BWRVIP category B inspection scope is for the H3, H4, H5, and H7 circumferential welds. The H3 weld connects the top guide ring to the shroud central upper cylinder. The H4 weld connects the shroud central cylinders. As discussed in Reference 4, WNP-2 is a BWR-5 and has two type H4 welds. The lower H4 weld was examined. The H5 weld connects the shroud central lower cylinder to the cole plate. The WNP-2 designator for the BWRVIP HS weld is H6A.

The H7 weld connects the shroud lower cylinder to the shroud support structure.

The examination cover.".ge exceeded the minimum required inspection. length (L g for each weld. Total weld length examined exceeded 50% for each weld. The examinations were performed on 100% of accessible weld lengths using the ultrasonic examination method.

No indication of stress corrosion cracking was detected. One planar flaw indication was detected in the lower H4 weld. This indication measured 3 inches long and 0.16 inch in

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depth. This length is 0.3% of the examined length. The signal characteristics of the

'indication were not indicative of stress corrosion cracking. The following table summarizes the examination results.

',Veld Number Weld Number  % Weld  % of Accessible  % of %of (WNP-2) (8WRVIP) Examined Region Examined Examined Examined Length Flawed Length Cracked H3 H3 67.6 100 H5 (lower H4 75.2 100 0.3 BWRVIP H4 H6A H5 75.2 100 H7 H7 50.6 100

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30-DAY REPORT OF INSPECTION RESULTS, GL 94-03, "INTERGRANULAR STRESS CORROSION CRACKING OF CORE SHROUDS" Sho6I'd you have any questions or desire additional information regarding this matter, please eall CM King at (509) 377-4515 or PJ Inserra at (509) 377-4147.

Respectfully, R. L. Webring Chief Executive Officer (Acting)

Mail Drop 1023 cc: EW MerschofF- NRC RIV C Poslusny, Jr. - NRR KE Perkins, Jr. - NRC RIV, Walnut Creek Field OIIice

• 'L NRC Sr. Resident Inspector - 927N Williams - BPA/399 PD Robinson - Winston & Strawn

STATE OF WASHINGTON )

Subject:

30-Day Report of

) In 'onR ul L 4-COUNTY OF BENTON )

I, R. L. WEBRING, being duly sworn, subscribe to and say that I am the Acting Chief Executive Officer for the WASHINGTON PUBLIC POWER SUPPLY SYSTEM, the applicant herein; that I have the full authority to execute this oath; that I have reviewed the foregoing; and that to the best of my knowledge, information, and belief the statements made in it are true.

DATE , 1998 R. L. Webring Acting Chief Executive Officer On this date personally appeared before me R, L. Webring, to me known to be the individual who executed the foregoing instrument, and acknowledged that he signed the same as his free act and deed for the uses and purposes herein mentioned.

GIVEN under my hand and seal this ~today of 0 1998 Notary Public in and for the STATE OF WASHINGTON Residing a My Commission Expires

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