ML20081C849

Interim Deficiency Rept Re Cracks in Containment Penetration Welds.Initially Reported on 840209.All Welds Repaired Per ASME Code,Section Iii,Subsection Nc

ML20081C849
Person / Time
Site:	Vogtle
Issue date:	03/07/1984
From:	Foster D GEORGIA POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
GN-326, NUDOCS 8403150043
Download: ML20081C849 (4)

Text

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8 Georg:a Power Company -

l Route 2. Box 299A Waynesboro, Georgia 30830 Telephone 404 554 9961 404 724-8114 34 MAR 12 P I : 0 7 Vogtle Project March 7, 1984 United States Nuclear Regulatory Commission File: X7BG03-M56 Office of Inspection and Enforcement Log: GN-326 Region II-Suite 3100 101 Marietta Street Atlanta, Georgia 30303

Reference:

Vogtle Electric Generating Plant-Units 1 and Z. 50-424, 50-425; Containment Penetration Welds Attention: Mr. James P. O'Reilly Gentlemen:

On February 9,1984, Mr. R. E. Folker of Georgia Power Company re-ported a potential defic ency to Mr. John Rogge of the USNRC concerning i

cracks in the centainment penetration welds. After conducting an en-gineering evaluation to review this item, Georgia Power Company has concluded that it is. reportable as a significant deficiency and a sub-stantial safety hazard. Based upon NRC guidance in NUREG-0302, Revision 1, Georgia Power Company is reporting this event as a si ficiency pursuant to the requirements of 10 CFR E0.55(e)gnificant .

de-A copy of the evaluation of this concern is attached for your information.

This response contains no proprietory information and may be placed in the NRC Public Document Room upon receipt.

,r Yours truly/ /

/

D. O. Foster

~,L REF/D0F/tdm Attachment xc: U. S. Nuclear Regulatory Commission Document Control Desk Washington, D. C. 20555 xc: R. J. Kelly D. E. Dutton J. A. Bailey L. T. Gucwa R. E. Conway W. F.. Sanders 0. Batum M. Malcom G. F. Head R. H. Pinson- G. Bockhold H. H. Gregory, III C. W. Hayes P. D. Rice B. M. Guthrie J. T. Beckham, Jr.

D. M. MacLemore R. A. Thomas E. D. Groover J. L.-Vota 8403150043 840307 UNFIIdi, COPY gDRADOCK05000 gp

a EVALUATION FOR A SUBSTANTIAL SAFETY HAZARD EVALUATION FOR A SIGNIFICANT DEFICIENCY Containir. ant Penetration Welds Initial Report:

On February 9,1984, Mr. R. E. Folker of Georgia Power Company reported a potential deficiency to Mr. John Rogge of the USNRC concerning cracks in the containment penetration welds.

Background Information:

A welded assembly is used to seal the containment building wall at loca-tions where system piping passes through the wall. The identified discre-pancies are located in the connecting weld between the flued-head of tne penetration assembly and the containment wall penetration sleeve.

Penetration weld radiographs have been reviewed to ensure that no hot cracks resulted from the use of type 309L weld wire. During this review, Georgia Power Company (GPC) found indications in four penetration pipe spool weld radiographs that were not noted in the Pullman Power Products original radiographic examination report. These four radiographic films were included in GPC Deviation Report MD-5325.

The deficient welds were subsequently reradiographed by Pullman Power Products using more sensitive film (Kodak "R") and refined technique to improve the radiographic film image of the indications. The more sensi-tive radiographic examination technique resulted in an improved interpre-tation and confirmed the presence of rejectable indications. Table 1 lists the results of the two separate radiographic examinations.

Engineering Evaluation:

An evaluation was conducted to determine if the "as found" condition could have impaired the safe operation of the plant. The weld deficiencies locally constitute areas where large stress intensifications exist. The stress intensifications, when added to the existing post welding residual stresses, reduce the calculated local structural margin of safety. The possibility exists that the discrepancies could propagate into a localized through-wall crack. Through-wall cracks would not have affected the structural integrity of the penetration assemblies but could allow post-accident leakage rates that result in the exceeding of the offsite dose guidelines of 10 CFR 100.

Conclusion:

Since the potential exists for the exceeding of the offsite dose limits of 10 CFR 100, it has been concluded that the event constitutes a significant

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• Containment Penetration Welds j Page Two l

deficiency and a substantial safety hazard. Based upon NRC guidance in NUREG-0302, Revision 1, Georgia Power Company is reporting this event

} under the reporting requirements of 10 CFR 50.55(e).

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[ Corrective Action:

1 All welds have been repaired in accordance with the ASME Code,Section III, Subsection NC.

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l TABLE 1 RESULTS OF REVIEW OF RADIOGRAPHIC FILM ON PENETRATION WELDS Deficiency Reported After Penetration Information* . Deficiency Reradiograph

! Radiograph Reported In with "R" Type

Sketch No/ Penetration No/ Type MD-5325 Film SKQ79/11/III Linear Incomplete Fusion Indication SKQ92/31/II Crater Crack Crater Crack 4

SKQ126/71/III Linear Crack and Incomplete Indication Fusion

, SKQ127/72/III a. Incomplete a. Incomplete

Fusion Fusion B. Linear b. Ircomplete Indication Fusion

• Refer to Drawings: 1X4DL4A13, 1X4DL4A14 4

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