ML20045G712
| ML20045G712 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 07/02/1993 |
| From: | J. J. Barton GENERAL PUBLIC UTILITIES CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| C321-93-2174, GL-88-20, NUDOCS 9307150084 | |
| Download: ML20045G712 (2) | |
Text
.
GPU Nuclear Corporation -
u U YMClear n,e rg er 88 p
o Forked River, New Jersey 08731-0388 609 971-4000 Wnter's Direct Dial Nurnber:
July 2,1993 C321-93-2174 U. S. Nuclear Regulatory Commission Attention:
Document Control Desk Washington, D.C.
20555 Gentlemen:
Subject:
Oyster Creek Nuclear Generating Station (OCNGS)
Operating License No. DPR-16 Docket No. 50-219 i
Generic Letter 88-20, " Individual Plant Examinations for Severe Accident Vulnerabilities (IPE)"
The OCNGS response to NRC Generic Letter 88-20 was submitted on August 14, 1992 (C321-92-2201).
The IPE Submittal Report, Section 8.1.2.2, indicated that implementation of a portable DC generator and equipment necessary to supply essential loads would be considered for procurement as a possible cost-effective improvement for use in coping with long term losses of DC power following a station blackout event and subsequent failure of the installed alternate AC power sources.
This letter provides the current status of the feasibility study for implementation of a portable DC power generator.
The existing DC power supply design provides redundant safety related 125VDC station batter %s which supply separate Safety Division A and B loads.
These
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batteries are designed to provide emergency power for a minimum of 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />. A separate station battery supplies normal power to non-safety related loads. For short term loss of DC power, continued power to the DC electrical divisions is provided through the battery chargers.
For long term loss of DC power, due to complete battery discharge in a station blackout (SBO) event, and postulating failure of the SB0 alternate AC power sources, temporary AC generators could be readily obtained through an outside supplier.
A portable AC generator would restore DC power through the battery chargers, and provide a comparable enhancement for coping with a postulated long term loss of DC. power.
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C321-93-2174 Page 2 Additionally, further consideration indicates that portable 125VDC generators are not readily available from electrical suppliers, and permanent installation requires significant engineering and design. Implementation of an alternate DC power source therefore does not provide a cost effective reduction in the overall risk significance of loss of DC power events.
Therefore, procurement and installation of a portable DC power supply will not be pursued. However, an OCNGS accident management guideline will be considered to address loss of DC power events, including use of portable AC power supplies as outlined above.
Accident management guidelines are planned for completion following the issuance of generic NRC guidance on accident management guideline implementation. Final scheduling will be in accordance with the OCNGS Integrated
- Schedule, if you have any questions on this information, please contact David J. Distel, Senior Licensing Engineer at 201-316-7955.
Since ely,
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(\\&O, J.
Bar on I ent and Director 2 Pres 4
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" eek JJB/DJD/amk cc: Administrator, Region I NRC Resident Inspector Mr. Alex Dromerick, Jr., Project Manager J. Butler, NUMARC