ML19321A061

Status Deficiency Rept 2 Re Damage to Intermediate Metallic Conduit.Extent & Safety Implications Remain Under Investigation.Final Rept to Be Provided No Later than 801006

ML19321A061
Person / Time
Site:	Grand Gulf
Issue date:	07/15/1980
From:	Mcgaughy J MISSISSIPPI POWER & LIGHT CO.
To:
References
AECM-80-151, NUDOCS 8007220389
Download: ML19321A061 (3)

Text

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MISSISSIPPI POWER & LIGHT COMPANY Helping Build Alississippi ,

I ', EdiddMdanB P. O. B O X 1640, J AC K S O N. MIS SIS SIP PI 3 9 2 0 5 V

mun pnocucticN oEPARTMENT July 15, 1980 Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, N.W.

Suite 3100 .

Atlanta, Georgia 30303 Attention: Mr. J. P. O'Reilly, Director

SUBJECT:

Grand Gulf Nuclear Station Units 1 and 2 Docket Nos. 50-416/417 File 0260/15525/15526 PRD-80/20, Status Report #2, Damage to Intermediate Metallic Conduit AECM-80/151

Reference:

AECM-80/101, 5/14/80 On April 14, 1980, Mississippi Power & Light Cort.pany notified Mr. F. Cantrell of your office of a Potentially Reportable Deficiency (PRD) at P.he Grand Gulf Nuclear Station (GGNS) construction site.

The deficiency concerns damage to Intermediate Metallic Conduit (IMC) resulting from adjustable threading dies.

The extent and safety implications of this deficiency remain under investigation. We expect'to provide our final report and de-termination of reportability no later than October 6, 1980. Our status report on PRD-80/20 is attached.

Yours truly,

%y J. P. McGaughy, Jr.

Assistant Vice President, Nuclear Production 1 l

ATR:mt I l

Attachment 8007220 k Member Middle Sout.h Utilities System

M12Tl!.TIPPI POWER O LIGHT COMPANY Mr. J. P. O'Reilly AECM-80/151 '

NRC Page 2 cc: Mr. N. L. Stampley Mr. R. B. McGehee Mr. T. B. Conner .

Mr. Victor Stello, Director Division of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D.C. 20555 t_ .

~ * * * ' Attachmant A to AECM-80/151 Pcgs 1 of 1 -

STATUS REPORT #2 ON PRD-80/20 I. Description of Deficiency The original description of the deficiency stated that adjustable threading dies had caused damage to Intermediate Metallic Conduit (IMC). 'It appeared the dies cut too deeply into the walls of the conduit, thus leaving sharp edges and burrs on the conduit interior which caused cable insulation damage when*the cables were instal-led in the conduit. Investigation determined the condition existed with_only 2' inch ~and larger threaded metallic conduit and was not limited to only IMC.- It has been determined that improper adjust-ment and use of dull dies along with too many threads being cut on the.end of the conduit resulted in the inward extrusion of small, sharp pieces of metal when the conduit " bottomed out" on the inner lip of conduit type fittings.

II. Safety Implications

- An evaluation of safety impact, based on damaged cables, will .

' be made on completion of f a review of the results of the reinspec-tion of affected conduit.

III. Corrective Actions All two inch and larger threaded metallic conduit with condulet type fittings has been reinspected for sharp edges and burrs.

Discrepant conditions have been documented and corrective actions are in process.

. Electrical craft personnel have been re-instructed in the proper method of threading metallic conduit.

-This deficiency is being tracked by Bechtel Management Corrective Action Report (MCAR)-GGNS No. 74.

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