ML20128J016

Suppls 850402 Response to Violations Noted in Insp Repts 50-424/84-36 & 50-425/84-36.Corrective Actions:Reexam & Evaluation of Representative Sample of Previous Ultrasonic Exams Performed.Results Acceptable in All Cases

ML20128J016
Person / Time
Site:	Vogtle
Issue date:	06/14/1985
From:	Foster D GEORGIA POWER CO.
To:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
GN-641, NUDOCS 8507100347
Download: ML20128J016 (3)

Text

Georgia Power Company g Poute 2 Box 299A Waynesboro, Georgta 30830

, Tefephone 404 554 9961. 6t 3360 404 724 8114, E t 3360 m

D. o. Foster Georgia Power the southem electic system c'e e f a ge Vogt!e Project United States Nuclear Regulatory Commission File: X7BG10j Office of Inspection and Enforcement Log: GN-641[,

Region II - Suite 2900 g 101 Marietta Street, Northwest Atlanta, Georgia 30323 G

Reference:

50-424/84-36, 50-425/84-36 y

' Attention: Mr. J. Nelson Grace [

cn The Georgia Power Company wishes to submit the following supplemental information to our response (GN-571, dated April 2, 1985) to USNRC Inspection Report 50-424, 425/84-36.

Violation 50-424, 425/84-36-01 identified two specific cases of failure by Pullman Power Products personnel to follow nondestructive examination (NDE) procedures. In one case, magnetic particle examinations were conducted without verifying magnetic field adequacy with a magnetic field indicator. In the other case, ultrasonic thickness examinations were conducted without performing an intermediate thickness verification.

In its response, Georgia Power Company indicated that additional evalua-tions would be conducted to establish a confidence level for the adequacy of previous nondestructive -examinations of the types identified in the l

violation. The additional evaluations have been completed and are summarized below: ,

I l 1. Ultrasonic Thickness Measurements - Pullman Power Products conducted a re-examination and evaluation of a representative sample of pre-vious ultrasonic examinations performed by the technician involved in the specific case cited in the violation. A total of forty-eight examinations were performed by the technician prior to the NRC l inspection. Using Military Standard 105-D to produce an acceptable sample size, eight of the forty-eight examinations were randomly selected for re-evaluation. Re-examination results were evaluated and were found to be acceptable in all cases.

2. Magnetic. Particle Examinations - Pullman Power Products conducted l

an evaluation of the technique cited in the violation to determine l . the reliability of examination results when a magnetic field indi-l cator is not used. The evaluation included a series of examinations of test specimens with known surface and subsurface defects using established techniques of yoke pole placements. The test examina-tions were conducted without the use of a magnetic field indicator hDR D WO 24

! G PDR g

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. Page'Two 5 with a standard Y-6 yoke. Since the current output is not adjustable using . the yoke with alternating current, the magnetic field strength is . constant on the part' being examined; therefore, the only variable involved is pole placement. -The test examinations were then repeated

, using.a magnetic field indicator to verify that an adequate magnetic field was . established. The evaluation concluded that all of the known surface-indications and even some of the subsurface indications were detected using the established pole placement techniques.

, Magnetic. field strength was shown to be well established for flat weld configurations and adequate, though somewhat reduced, to detect surface discontinuities in corner welds and terminations.

Based on the results of these evaluations, it is Georgia Power Company's position that adequate confidence levels have been established for the adequacy of previous nondestructive examinations of the types identified in the violation and that no additional corrective actions other than those described in our response of April 2,1985, are required.

Violation 50-424, 425/84-36-03 identified a failure in Pullman Power Products procedures to provide or reference required manufacturer instructions for the installation of spring hangers and pipe clamps.

As a result, Pullman Power Products personnel installed and inspected pipe support components without details of the manufacturer's instruc-tions. In its response, Georgia Power Company indicated that a sampling program would be established to determine the acceptability of previously j installed pipe supports requiring the use of manufacturer instructions, and committed to provide a report to the NRC by June 15, 1985, giving either the results of the sample evaluation or a schedule for its com-pletion. The status and schedule for completing the evaluation is presented in the following summary:

1. The population of pipe . supports installed and inspected prior to the correction of Pullman Power Products' procedure have been identi-fied and listed. The list consists of approximately 3300 supports.

2. Using standard statistical sampling techniques designed to provide a representative sample of the entire population, fifty-nine supports were randomly selected from the list for reinspection.

3. Pullman Power Products is presently developing a reinspection program for the specific pipe support attributes for which manufacturer instructions are required. Reinspection of the sample of fifty-nine

supports is expected to begin by July 1, 1985.

4. The results of the reinspection will be submitted to Georgia Power Company by July 20, 1985. All nonconformances will be reported and dispositioned through established procedures.

5. Georgia Power Company and Bechtel Power Corporation, the Vogtle

Project architect / engineer, will evaluate the results of the re-inspection and determine if any additional actions are required.

This evaluation is expected to be completed by mid-August.

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.Page Three l

Based on this schedule, Georgia Power Company expects to provide  !

a . report to 'the - NRC by August 30, 1985, giving the results of this evaluation.

This report contains no proprietary information and may be placed in the NRC Public Document Room.

Yours truly,

/

. . o'ste REF/D0F/tdm xc: U. S. Nuclear Regulatory Commission Document Control Desk Washington, D. C. 20555 R. J. Kelly J. A. Bailey G. Bockhold R. E. Conway 0. Batum P. D. Rice G. F. Head H. H. Gregory C. S. McCall (OPC)

J. T. Beckham W. T. Nickerson E. L. Blake, Jr.

R. A. Thomas D. R. Altman (Shaw, et. al.)

D. E. Dutton D. L. Kinnsch (BPC) J. E. Joiner W. F. Sanders (NRC) J. L. Vota (W) (Troutman, et. al.)

R. H. Pinson L. T. Gucwa D. C. Teper (GANE)

B. M. Guthrie C. E. Belflower L. Fowler (LEAF)

E. D. Groover F. B. Marsh (BPC) T. Johnson (ECPG)

R. W. McManus G. A. McCarley -

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