ML18142B222

LER 1977-008-00 for R.E. Ginna, B Steam Generator Tube Leak

ML18142B222
Person / Time
Site:	Ginna
Issue date:	07/18/1977
From:	White L Rochester Gas & Electric Corp
To:	O'Reilly J NRC/IE, NRC Region 1
References
LER 1977-008-00
Download: ML18142B222 (7)

Text

NRC FORM 196 I2 76 I U,S, NUCLEAR REGULATORY Cob.<<<<SSION DOCKET NUMBER rQRC DISTRIBUTION FQR PART 50 DOCKET MATERIAL FILE NUMBER TO:<<Mr-James P.OIReilly FROM: Rochester Gas 6 Elec Corp Rochester, Ni Yi L.D White, Jr.DATE OF DOCUMENT 7/18/77 DATE RECEIVED 7/21/77 TTE R Cl ORIGINAL Y DESCRIPTION QNOTORIZED

~~LASS I F I E D PROP INPUT FORM ENCLOSURE NUMBER OF COPIES RECEIVED p QfQ>>yg E9, License'e Event Report (RO 50-244/77-08) on 7/5/77 concerning the Air Ejector and Blowdown rad2Iation monitors alarming~~.~~.PLANT NAME: Ginna Unit No~(1-P)(2-P)RJL 7/21/77 NOTE: IF PERSONNEL EXPOSURE IS INVOLVED SEND DIRECTLY TO KREGER/J.COLLINS FOR ACTION/INFORMATION C.INTERNAL D IST RI BUTION EXTERNAL DISTRIBUTION CONTR NUMBER ACRS 16 SENT AS AT Q2$3 NRC FORM 196 (2-76)

T r i/i Ji'"II.'"(i'oili?Il7Tin67 ROCHESTER GAS AND ELECTRIC CORPORATION

~I1~DAI~bO o 89 EAST AVENUE, ROCHESTER, N.Y.14649 LEON O.WVHITE.JR, YIrc pRcsIDENT TCCCo><DNC AIICA rDDC VIII 546.2700 July 18, 1977 Mr.James P.O'Reilly, Director U.S.Nuclear Regulatory Commission Office of Inspection and Enforcement Region I 631 Park Avenue King of Prussia, Pennsylvania 19406"'igyggtIttafff 00cket Fltjn Subj ect.Reportable Occurrence 77-08 (14-day report),"B" Steam Generator tube leak R.E.Ginna Nuclear Power Plant, Unit No.1 Docket No.50-244

Dear Mr.O'Reilly:

In accordance with Technical Specifications, Article 6.9.2.a, the attached report of Reportable Occurrence 77-08, 14-day, is hereby submitted.

Two additional copies of this letter and the attachment are enclosed.Very.truly yours, L.D.White, Jr.Attachment cc: Dr.Ernst Volgenau (40)Mr.William G.McDonald (3)COIAIAI 77gp2p233 I 1 r f 77 I Fl e CONTROL BLOCK LER 77-08/1T I LICENSEE EVENT REPORTS fPlEASE PRINT ALL REQUIRED IMFORMAT(OM) e LICENSEE NAME QO1j N Y R E 7 89 CATEGORY IQO1]ooN1~7 8 57 58 G 1 0 14 15 REPORT REPORT 59 60 LICENSE TYPE 4 1 1 1 1 25 26 30 LICENSE NUMBER 0-0 0 0 0 0-0 0 EVENT TYPE 3'I 32 ,DOCKET NUMBER EVENT DATE REPORT DATE 0 5 0-0 2 4 4 0 7 0 5 7 7 0 7 1 8 7 7 61 68 69 74 75 80 EVENT DESCRIPTION Qpg During normal operations the Air Ejector and blowdown radiation monitors alarmed.7 8 9 80 I Analysis of the B Steam Generator blowdown verified Iodine activity from a calculated 7 8 9 80 I Eddy Current testing was erformed to determine if a attern of degradation existed.7 8 9 80 IOOI About 300 tubes were examined which included tubes in (cont'd.on attached sheet)80 7 8 9 PRI4IE SYSTEM CAUSE COMPONENT CODE CODE COMPONENT CODE SUPPLFM VOLATION[887I~CB E II T E X C II~N N 7 8 9 10 11 12 17 43 44 47 CAUSE DESCRIPTION l00m The failure of the tube R45C54 and the defect indications in tubes R44CSS, 56, 57 and COMPONENT MANUFACTURER W 1 2 0 48 7 8 9 80[os 58 are postulated to be caused by stress corrosion cracking from the inside surface of 7 8 9 80~10 the tubes.These inside diameter cracks are theorized to be (cont'd.on attached sheet)7 89 80 t00~j leak rate of 0.006 gpm.The leaking tube was located with a hydrostatic test, and OTHER STATUS OFFSITE CONSEQUENCES 7 89 FACILITY STATUS ee powER I111j E~io o NA 7 8 9 10 12 13 FORM OF ACTIVITY COATENT RELEASED OF RELEASE AMOUNT OF ACTIVITY KO'~j L~l NA 7 8 8 10 11'ERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION

~18~OO O E NA 7 8 9 11 12 13 PERSONNEL INJURIES NUMBER DESCRIPTION

~4~oo o NA 7 89 11 12 METHOD OF DISCOVERY c 44 45 46 44 45 80 DISCOVERY DESCRIPTION Rad monitors and sample analysis 80 LOCATION OF RELEASE NA 80 80 News release.ADDITIONAL FACTORS 7 89@~75 7 8 9 LOSS OR DAMAGE TO FACILITY TYPE DESCRIPTION Q~g p, 7 89 10 PUBLICITY[i<~]7 89 NA NA 80 80 80 80 7 89 A~E 4 Curtis III 80 PHDNE.7 1 6 546-2 700, ext~22 63 ciao eeI-eev Licensee Event Report Seportable Occurrence SO-244/77-08 Event Descri tion (cont'd.)the area of the leaking tube and other selected areas with previous indications.

These examinations revealed four additional tubes, in the area of the leaking tube, with similar (ID)indications.

These four tubes and the leaking tube were explosively plugged.(Reportable Occurrence 77-08, 14-day).Cause Descri tion (cont'd.)caused by a dent at:he tube to tube sheet interface which induces stress into the tube wall resulting in cracking.There are not any chemical species postu-lated to be involved in this cracking phenomena due to the purity of the primary system's water, which flows through the tubes.Corrective action taken included eddy current examination of surrounding tubes and tubes in areas where previous inservice inspections had revealed small defect indications.

There were no other tubes identified of those examined which exhibited further degradation.

Therefore, the failed tube and four others with similar (ID)indications were plugged.Further investigation is continuing with Westinghouse and RQ&E personnel involvement studying the generic PWR tube failure problem.At the next refueling outage, an inservice inspection of the steam generator tubes will include tubes in the area of this failure.

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