ML20072L475
| ML20072L475 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 06/20/1983 |
| From: | Tucker H DUKE POWER CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| REF-SSINS-6820 IEB-83-3, NUDOCS 8307140067 | |
| Download: ML20072L475 (4) | |
Text
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DUKE POWER GOMP gA P.O. nox 33180 CllARLOTTE, N.C. 28242 IIAL II. TU(.KER Ten.errio n June 20,19830a JUil U Aiu. O O n6 n
1M e (704) 373-4531 vna,ar.sment 6w
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Mr. James P. O'Reilly, Regional Administrator U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30303
Subject:
Oconce Nuclear Station Docket Nos. 50-269, -270, -287
Dear Sir:
As specified in IE Bulletin 83-03 dated March 10, 1983 concerning check valve failures used in diesel generator water cooling systems, please find attached a report providing a response to Item 4.
The only on-site diesel generator at Oconee is associated with the Standby Shutdown Facility (SSF) and,thus, the only check valve of concern is valve number CCW-284. The report providing the results of the initial valve integrity verification, as requested by Item 5, will be submitted within 90 days of completion of the initial checkout of the diesel generator within the SSF system.
I declare under penalty of perjury that the statements set forth herein are true and correct to the best of my knowledge, executed on June 20, 1983.
Very truly yours,
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Hal B. Tucker PFG/php Attachment (1) cc: Document Control Desk U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Mr. J. C. Bryant NRC Resident Inspector Oconee Nuclear Station Mr. John F. Suermann Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555 i
8307140067 830620 PDR ADOCK 05000269 o
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Ci JP0/PFG June 20, 1983 Duke Power Company Oconee Nuclear Station Response to IE Bulletin 83-03 Item 4 Request 1 Licensees are requested to review the plant Pump and Valve In-Service Test (IST) program required by Section XI of the ASME Boiler and Pressure Vessel Code and modify it if necessary to include check valves in the flow path of cooling water for the diesel generators from the intake to the discharge.
Those portions of the cooling water system which do not directly supply the diesel may be excluded from this review. For example, if the cooling water to the diesel is supplied by the normally operating service water system, the loop of piping to the diesel from the service water piping and back must be considered, but not the complete service water system.
For those cooling water systems which come into operation only upon demand for diesel cooling, all portions of the system which are required to change state must be reviewed.
Response 1 The sources of emergency electric power for each Oconee unit are the on-site Keowee hydro electric units instead of the usual diesel generators found in other nuclear power plants. The only on-site diesel generator is associated with the Standby Shutdown Facility (SSF) which is in the process of being installed to meet the fire protection requirements of 10 CFR 50, Appendix R.
The Oconee Nuclear Station's Pump and Valve In-Service Test (IST) program was reviewed to assure that all check valves in the flow path of cooling water for diesel generators from the intake to the discharge were included in the IST program. The only check valve, as described by the bulletin, of concern is valve number CCW-284 located within the SSF system. This check valve was identi-fled in a November 14, 1982 letter from H. B. Tucker to H. R. Denton which identified changes to the IST program. Thus, a modification of the IST program to include this check valve is not necessary.
Request 2 For the valves described in (1) above, licensees are requested to examine the IST program and modify it if necessary to include verification procedures that confirm the integrity of the valve internals. This may be accomplished by using both a forward flow and a back flow test or by valve disassembly and inspection. Other equally effective means of assuring integrity of the valves may be used. A reasonable schedule for the test of these valves shall also be included in the IST program.
Response 2 Attached.is a simplified diagrammatic lcyout of the SSF Auxiliary Service Water (ASW) system. The valve integrity will be verified by using a forward
JP0/PFG June 20, 1983 flow and a back flow check.
These checks will be performed quarterly.
The forward flow check will be made when the SSF diesel engine service water pump (DESWP) is tested. The back flow check will be made during the SSF ASW pump performance test, with the SSF DESWP off.
Request 3 Licensees are requested to submit the history of any known previous failures of these valves at your plant.
Response 3 Diesel generators havc never been previously used at Oconee; thus, there is no history of diesel generator check valve failures.
CCW-Cond:nsate Circulating Wit:r ASW-Auxiliary Service Water DESW-Diesel Engine Service Water DEHE-Diesel Engine Heat Exchanger From ASW l
2 nd 2B CCW-289 1CCW-268 CCW-266 P-2 i f ump CCW-283 Y
P-5 Z
CCW-284 2CCW-268 CCW-285
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DEHE DEHE (North End)
(South End) p
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To if 1 f X
M CCW c
CCW-310 Orifice CCW-267 Assembly
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