ML20069G681

Responds to NRC Re Violation Noted in Insp Repts 50-369/94-08 & 50-370/94-08.Corrective Actions: PIP 0-M93-1253 Initiated & Present & Past Operability Evaluations W/Regard to Compliance W/Ts 3.4.6.2 Initiated

ML20069G681
Person / Time
Site:	McGuire, Mcguire
Issue date:	06/01/1994
From:	Mcmeekin T DUKE POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9406100112
Download: ML20069G681 (3)

Text

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), 11 1 Dukeit>wer Company T C hlchtmur McGuire NucIcar Generatwn Depoonent Lice President i2700Ilagers Ferry Rced(MG01\P) (704)8754800 fluntehville. NC250?it8b85 (704)5754809Far l DUKEPOWER l

June 1,1994 I i

U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555

Subject:

McGu!re Nuclear Station, Units 1 and 2 Docket Nos. 50-369 and 50-370 NRC Inspection Report No. 50-369, 370/94-08 Violation 50-369,370/94-08-01 Reply to a Notice of Violation Gentlemen:

Enclosed is the response to the Notice of Violation issued May 6,1994 concerning a non-conservative unidentified reactor coolant leakage calculation.

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Should there be any questions concerning this response, contact Randy Cross at (704) 875-4179.

Very Truly Yours, 7/@/

. C. McMeekin Attachment xc: (w/ attachment)

Mr. S. D. Ebneter Mr. George Maxwell Regional Administrator, Region il NRC Senior Resident inspector U.S. Nuclear Regulatory Commission McGuire Nuclear Station 101 Marietta St., NW, Suite 2900 Atlanta, Georgia 30323 Mr. Victor Nerses U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation One White Flint North, Mail Stop 9H3 Washington, D. C. 20555 I

1 9406100112 940601 PDR ADOCK 05000369 O PDR }i t

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McGuire Nuclear Station {

Reply to a Notice of Violation Violation 369. 370/94-08-01 Technicai Specification 3.4.6.2 requires that the unidentified leakage rate shall not exceed one gallon per minute while in Modes 1,2,3, and 4.

Contrary to the above, unidentified leakage rate exceeded the technical specification limit on at least twelve occasions during the past twelve months prior to December 7,1993 while in Modes 1, 2, 3, and 4.

This is a Severity Level IV violation (Supplement 1).

_RJplylo Violation 3ft9. 370/94-08-01

1. Reason for the Violation:

The reason for the violation is failure to consider the system / component interaction in the original design of the program for the reactor coolant (NC) system leakage calculation. The calculation did not recognize inputs of water from other systems to the reactor coolant system drain tank (NCDT) and pressurizer relief tank (PRT).

Failure to recognize these potential inputs and the subsequent effect on the calculation logic could have caused the calculation to be non-conservative. Since plant personnel had not been aware of these potential inputs being accounted for as identified leakage, they were unaware of potentially exceeding the 1 gpm Technical Specification limit. Because they were unaware, n-.

actions were taken to reduce the leakage or shutdown as required by the Technical Specification.

2. Cgr_rective sLeps that have been taken and the results achieved:

a. Systems Engineering personnel initiated PIP 0-M93-1253 to investigate the circumstances surrounding the problem and determine appropriate corrective actions.

b. Systems Engineering personnel initiated present and past operability evaluations with regard to compliance with Technical Specification 3.4.6.2.

c. Instrumentation and Electrical (IAE) personnelimplemented Temporary Modi :4 ions 6314 and 6315 to eliminate inputs to the NCDT drain header which are not NC system related.

d. Systems Engineering personnel verified that potential for Cold Leg Accumulator drain and drain header inputs of refueling water storage tank (FWST) water to the NCDT were removed.

e. Operations personnel changed procedures PT/1 & 2/A/4150/01B, Reactor Coolant Leakage Calculation, to conservatively lock out the input from PRT level increases.

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3. Corrective steps that will be taken to avoid further violations: I

a. Mechanical Nuclear Engineering personnel will determine the best way to permanently remove non-NC system related inputs from the NC system leakage calculation. The evaluation for permanently removing inputs will be completed by July 5,1994.

b. Modification Engineering personnel will include appropriate information io the Design Basis Document (D8D) for the NC system to address the NC system leakage calculation and the consequences of introducing inputs from other systems into the calculation. The NC System DBD will be completed by December 31,1994.

4. Date when full compliance will be achieved:

Full compliance will be achieved by December 31,1994 2

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