ML19256F646

Final Deficiency Rept Re Use of Inadequately Supported Long Terminal Strip in Junction Boxes on Electrical Penetration Assemblies for Containment Bldg. Procedure to Brace CR151- Terminal Blocks for Electrical Penetration, Issued

ML19256F646
Person / Time
Site:	Grand Gulf
Issue date:	12/03/1979
From:	Dale L MISSISSIPPI POWER & LIGHT CO.
To:
References
AECM-79-136, NUDOCS 7912190702
Download: ML19256F646 (2)

Text

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~0 MISSISSIPPI POWER &'l_lGHT COMPANY

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Helping Build Mississippi P. O . B O X 16 4 0, J A C K S O N... MIS SIS pl i39205 anoouction or,a nvu e=7 December 3, 1979 Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, N. W., Suite 3100 Atlanta, Gecrgia 30303 ATTENTION: Mr. J. P. O'Reilly, Director Gentlemen:

SUBJECT:

Grand Gulf Nuclear Station File 0262/0498/15525/15526

-Docket Nos. 50-416/417 Final Report for PRD 79/19

. as Defined in 10 CFR 50.55(e)

AECM-79/136 On October 10, 1979, Mississippi Power & Light Company notified Mr. J. Wilcox of your office of a potential reportable deficiency con-cerning cracking, breaking, or sagging teminal strips in Westinghouse electrical penetration assemblies. We have now determined that this is a reportable deficiency within the meaning of 10 CFR 50.55(e). If this condition had gone undetected, it could have affected adversely the safety of operations of the nuclear power plant.

The ssTety implication is a postulated event where a oroken strip may cause an electrical short circuit between two conductors of a safety-related assembly. This condition could jeopardize the safe operatien of the plant.

This deficiency involves the use of inadequately supported long teminal strips in junction boxes on electrical penetration assemblies for the con-tainment building. The teminal strips are "'ype CR151-D7 manufactured by the General Electric Company. The junction box and penetrations are manu-factured and supplied by Westinghouse Electric Corporation, Horseheads, N. Y.

As corrective action, Westinghouse has issued a " Procedure to Brace CR151 - Teminal Blocks for Grand Gulf Electrical Penetration", PEN-TR-79-65, Rev. 1, 10/16/79. Af ter evaluation and approval by Bechtel Project Enginee r-ing, this procedure was transmitted on November 12, 1979 to the jobsite for ibplementation.

1626 332 g,7 ss 7912100 Member Middle South Utilit ystem d b l4L COPY. ,

MISSISSIPPI POWER & LIGHT COMPANY Mr. J. P. O'Reilly Page two Bracing of CR151 terminal strips will coc:mence af ter receipt of the required clamps from Westinghouse. All undelivered penetration junction boxes at the Westinghouse plant will include properly braced CR151 terminal blocks before shipment to the jobsite.

Details of corrective action will be summarized in Bechtel Management Corrective Action Report GGNS-57 and will be available for your review at the GGNS construction site.

6 Yours truly, L. F. Dale Nuclear Project Manager JBE/JDR:pa cc: Mr. N. L. Stampley Mr. R. B. McGehee Mr. T. B. Conner Mr. Victor Stello, Jr., Director '

Division of Inspection & Enforcement U. S. Nuclear Regulatory Cot: mission Washington, D. C. 20555 1626 433

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