ML20195H147
| ML20195H147 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 06/09/1988 |
| From: | Tucker H DUKE POWER CO. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| NUDOCS 8806280226 | |
| Download: ML20195H147 (2) | |
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DUKE POWER GOMPANY P.O. BOX 33189 CHARLOTTE, N.O. 28949
'HALB. TUCKER ruternown vmm emessnest
.(704) 073 4831
- smaan esosamos June 9, 1988 U.S.. Nuclear Regulatory Commission Document Control Desk Washington, DC~ 20555 Subj ect: 'Oconee Nuclear Station Docket Nos. 50-269, -270, -287 Non-Vital' Power Supply Used in Valve Interlock Logic
Dear Sir:
s The purpose of this. letter is to. respond to the NRC letter dated March 21, 1988 which transmitted information concerning potential problems involving the-capability-to establish post-LOCA recirculation flow due to failure of the non-vital' power supply used in valve interlock logic -at an operating Westinghouse - plant.
The NRC staff requested Duke Power Company (DUKE) to review the'information and determine the possible applicability of the concern to Oconee Nuclear Station.
The potential problem identified and the NRC concern involve the capability to open. valves in-the crossover piping between low pressure injection (LPI) pump discharge: and high pressure inj ection (HPI). pump suction to establish
- post-LOCA recirculation. The valves at the Westinghouse plant are. interlocked with 1 pressure transmitters to prevent possible overpressurization. of HPI suction piping.
The transmitters are supplied with non-vital. power and would block the' valves from opening if non-vital power f ailed.
The equivalent valves at Oconee are LP-15 and LP-16 on all three units. ' These valves provide the type of flow path described in the Westinghouse bulletin.
Howeveri the HPI inlet pressure at Oconee is protected by relief valves.
Therefore,. these discharge valves are not interlocked with pressure transmitters.
The motor operators on the valves are fed by a power source that is backed up by standby power in case of loss of offsite power.
MD 8806200226 800609 PDR ADOCK 05000269 l'
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Document Control Desk June-9, 1988 Page 2 In conclusion, Duke. has determined that the subject concern does not apply to Oconee Nuclaar Station.
Very-truly yours,
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Hal B. Tucker i
MAH/16/ bhp xc:
Dr. J. Nelson Grace Regional Administrator Region II U.S. Nuclear Regulatory Commission 101 Mariotta Street, NW, Suite 2900 Atlanta, Georgia 30323 Ms. Helen Pastis Office of Nuclear Regvlation U.S. Nuclear Regulato-ey Commission Washington, DC 20555 Mr. P. H. Skinner NRC Resident Inspector Oconee Nuclear Station
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