ML20238F788
| ML20238F788 | |
| Person / Time | |
|---|---|
| Site: | McGuire  |
| Issue date: | 09/03/1987 |
| From: | Tucker H DUKE POWER CO. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| NUDOCS 8709160348 | |
| Download: ML20238F788 (2) | |
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DUKE POWER GOMPANY
. P.O. Box 33189 CHARLOTTE, N.C. 28242
/HALB. TUCKER tetepuows vuon rassanswr
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(U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington,.D. C. 20555
Subject:
..McGuire Nuclear Station:
Docket Nos. 50-369 and 50-370 D
Licensee Event' Report 369/85-29 i
Submitted October 31, 1985
Dear Sir:
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' The-subject License Event Report 369/85-29 involved an event in which an analysis error in containment pressure was non-conservative. As part of the corrective actions, Duke committed to reevaluate the emergency procedure for the transfer to cold leg recirculation to determine whether it is acceptable to allow the Containment Spray (NS) Pump to remain running during the transfer. The Refueling Water Storage Tank (FWST) level setpoints would then be recalculated based on the revised procedure.
The analysis in question is the peak containment pressure transient. For the current Final Safety Analysis Report (FSAR) analysis, the' timing of key events is as follows:
Residual Heat Removal (ND) auxiliary spray initiated 3000 seconds NS Pump stopped for switchover 3320 seconds NS Pump restarted from sump-3500 seconds Ice bed meltout 4960 seconds Depending on'the assumptions made about the operator action time for valve manipulation and about FWST level instrument error, the NS Pump times can vary.
Depending on the assumption made about ice bed mass, the meltout time may be shifted earlier in time such that it occurs during or even before the time the NS Pump is stopped. There would then be a 180 second period (e.g., 3500 - 3320) with no NS spray and no ice. If the action time and level assumptions shift the NS Pump off period to before 3000 seconds, there would also be no ND spray.
It is.for these situations, if they occur, that it would be beneficial to eliminate the off period by leaving the pump running. Should this situation arise, an evaluation of the type described by the Licensee Event Report 369/85-29 commitment would indeed be made. However, since this is not currently and may never be the case, Duke rescinds this commitment.
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.U.?S.-Nuclear'Ragulatory Commission
! September 3, 1987.
Page'Two If there are any questions'regarding this matter, feel' free to contact Duke Licensing.
Very truly yours, e
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Hal B. Tucker EP. '
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SEL/127/sbn Attachment xc:
Dr. J. Nelson Grace, Regional Administrator U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 Mr. Darl Hood Office of. Nuclear Reactor Regulations U. S. Nuclear Regulatory Commission Washington, D.'C.
-20555
.INPO Records. Center Suite 1500 1100 Circle 75 Parkway Atlanta, Georgia 30339' Mr. W..T. Orders NRC Resident Inspector McGuire Nuclear Station
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