ML20066J177

Revised Final Deficiency Rept Re Nonsafety Sensing Lines on safety-related Receiver Tanks.Initially Reported on 810612.Orifice Will Be Installed Between Manual Isolation Valve & Reducer in safety-related Portion of Sensing Line

ML20066J177
Person / Time
Site:	Perry
Issue date:	11/15/1982
From:	Davidson D CLEVELAND ELECTRIC ILLUMINATING CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
10CFR-050.55E, 10CFR-50.55E, NUDOCS 8211230463
Download: ML20066J177 (2)

Text

.

THE CLEVELAND ELECTRIC ILLUMIN ATING COMPANY P O DOX $000 m CLEVELANo, OHIO 44101 e TELEPHONE (216) 622-9800 m ILLUMINATING BloG e 55 PUBLIC SOUARE Serving The Best Location in the Nation November 15, 1982 Dalmyn R. Davidson vice m smNr S r5T[U E NGINF f R!NG AND CONSTRUCTION Mr. James G. Keppler Regional Administrator, Region III Of fice of Inspection and Enforcement U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137 RE: Perry Nuclear Power Plant Docket Nos. 50-440; 50-441 Revised Final Report - Nonsafety Sensing Lines on Safety-Related Receiver Tanks [RDC 30(81)]

Dear Mr. Keppler:

This letter serves as a revised final report pursuant to 10CFR50.55(e) con-cerning safety-related receiver tanks for the Star.dby Diesel Generator Starting Air System being connected to nonsafety-related sensing lines through normally open, safety-related valves for both Units I and II. This was first reported by W. J. Kacer of The Cleveland Electric Illuminating Company to R. Warnick of your office on June 12, 1981. A final report on this subject was originally submitted to your office on July 13, 1981.

This report includes a description of the deficiency, an analysis of the safety implication, and a revision to the planned corrective action outlined in our report dated July 13, 1981.

Description of Deficiency Gilbert Associates, Incorporated (Architect / Engineer for the Perry Nuclear Power Plant) design drawings D302-351 and D352-351, outline the piping system for the Standby Diesel Generator Starting Air System (R-44 System). The design incorporates two air receiver tanks and starting air compressors per diesel generator. Each receiver tank is equipped with an air sensing line which automatically starts its corresponding air compressor on low pressure.

The air sensing line includes a manually operated isolation valve. The tank, the manual isolation valve, and the sensing line up to and including a reducer located downstream of the manual isolation valve are designed safety-related.

The remaining portion of the sensing line is designed as nonsafety-related.

Analysis of Safety Implications Failure of the nonsafety portion of the sensing line during a seismic event would result in blowdown through the sensing line of the receiver tank. There is no assurance with this design that the isolation valve could be manually closed in sufficient time to prevent blowdown of the tank below the minimum required pressure. Therefore, with these assumptions, the failure of the nonsafety line would impair the starting air safety function.

8211230463 821115 PDR ADOCK 05000440 S PDR NOV 1 8 082

_m Mr. Jrmeo C. Ksppler Nov:mber 15, 1982 J

Corrective Action Planned In our final report dated July 13, 1981, we stated that the existing isolation valves would be replaced with automatic isolation valves. After further study, this fix has been revised for reasons of reliability. The final corrective action will instead make use of an orifice. The orifice will be installed between the manual isolation valve and the reducer in the safety-related portion of the sensing line to limit the rate of blowdown from the receiver tank in the event of a break in the nonsafety portion of the sensing line.- By means of the Control Room Low Header Pressure Alarm, the operator is now given 30 minutes to isolate the receiver tank before the tank air pressure falls below the minimum limit sufficient for 5 diesel engine cranking cycles.

The referenced design drawings have been revised to incorporate the orifice.

The design activities have been completed. If you have any questions, do not hesitate to contact us.

Sincerely, had: A""

Dalwyn R. Davidson Vice President System Engineering and Construction DRD:pab cc: Mr. M. L. Gildner NRC Site Office Director i Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C. 20555 U.S. Nuclear Regulatory Commission c/o Document Management Branch Washington, D.C. 20555 Mr. R. Giardina Power Systems Branch U.S. Nuclear Regulatory Commission Washington, D.C. 20555 l

- _ _