ML20033G632
| ML20033G632 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 03/30/1990 |
| From: | Cutter A CAROLINA POWER & LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20033G633 | List: |
| References | |
| NLS-90-074, NLS-90-74, NUDOCS 9004100429 | |
| Download: ML20033G632 (2) | |
Text
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- Memph. N C !? eof WAR 3 01990 SERIAL:
NLS.90 074 A. 5 CUTTER vice Proeisent Nuc6 ear kvioso DepMment United States Nuclear Regulatory Commission ATTENTION: Document Control Desk Washington, DC 20555 BRUNSVICR STEAM ELECTRIC PLANT, UNIT NOS. 1 AND 2 DOCKET NOS. 50 325 & $0 324/ LICENSE NOS. DPR.71 & DPR.62 EVALUATION OF THE ELECTRICAL DISTRIBUTION SYSTEM TOR COMPLIANCE WITH CDC 17 Centlemen:
In response to the NRC Diagnostic Evaluation Team (DET) report for Brunswick Units 1 ant', 2. CP&L provided the staff an Integrated Action Plan (IAp), dated Sept 0mber 27, 1989, which included relevant Brunswick Plant and Corporate improvement actions.
Item D1 of the IAP committed to a reevaluation of the Brunswick electrical distribution system for compliance with CDC 17 by March 31, 1990 and a subsequent briefing of appropriate NRR personnel on the results of the evaluation.
In a letter dated November 1, 1989, the NRC identified four questions to be answered as pa**. of the Company's evaluation. provides the bases for how the Brunswick Plant satisfied the requirements of CDC 17 at the time of licensing and responses to questions 1 through 4 of the NRC's November 1, 1989 letter.
The Brunswick Plant was designed, built, and licensed in accordanco with 7EEE Standard 308 1971 d ich specifies that the preferred power supply consist of a minimum of one circuit from the transmission network norrr. ally availabic with a provision for alternate access to the transmission, network within eight hours of post accident unit shutdown.
The preferred power supply at the Brunswick Plant is provided by any one of four off site transmission circuits via the Startup Auxiliary Transformer (SAT).
In the event of a loss of the SAT, the diesel generators are available until backfeeding of the Unit Aux *.11ary T1ansformer (UAT) can be accomplished.
Backfeeding of the UAT is the alternats access to the trar.smission network.
As a result of this evaluation, CP&L has concluded that the BNP electrical cistribution system, as designed, meets the requirementa of CDC 17, as they were interpreted when the plant was licensed.
1 In response to the Station Blackout: Rule,10 CPR 50.63 CP&L committed to l
perform modifications to enhance the cross tie capability between the Unit 1 l
and the Unit 2 4160 VAC buses (CP&L letter NLS.89 256 dated October 10, 1989).
l These modifications will ensure that alternate AC power is available within 9004100409 900330 J
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Document Contr-1 Desk t
NLs.90 074 / Page 2 I
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one hour of the onset of a station blackout event.
Once this modification is l
complete, CP&L will revise the Brunswick Plant procedures to enhance the j
ability to cope with either a station blackout event or a loss of the i
preferred power supply coincident with unavailability of the unit's diesel i
generator (s) (CDC.17) event.
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Please refer any questions regarding this submittal to Mr. M. R. Oates at (919) 546 6063.
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Yours very truly,
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i Enclosure cc:
Mr. S. D. Ebneter Mr. N. B. Le Mr. V. H. Ruland i
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