ML20086K207

Environ RO 75-1:on 750124,second Fan Lost on Cooling Tower C & Cooling Tower a Lift Pump Removed from Svc.Caused by High Vibration.Fan Vibration Trips Reset & Fan Operated Satisfactorily

ML20086K207
Person / Time
Site:	Peach Bottom
Issue date:	02/03/1975
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Giambusso A Office of Nuclear Reactor Regulation
References
RO-75-1, NUDOCS 8401260350
Download: ML20086K207 (2)

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i PHILADELPHIA ELECTRIC COMPANY

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2301 MARKET STREET

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February 3, 1975 '%[j r g 9' # .

s Mr. A. Giambusso Director, Division of Reactor Licensing Office of Nuclear ~ Reactor Regulations United States Nuclear Regulatory Commission Washington, DC 20555

Subject:

Environmental Deviation The following deviations were reported to Mr. Tom Shedlowsky, N.R.C. Region i Office of Inspection and Enforcement and to Mr. T. Fabian of Pennsylvania Department of Environmental Resources on January 24, 1975

Reference:

License Number DPR-44/56 Environmental Technical Specifications Report No.: 50-277/278-75-1 Report-Date: February 3, 1975 Deviation Date: January 24, 1975 Facility: Peach Bottom Atomic Power Station Units 2/3 R.D. I, Delta, Pennsylvania 17314 Identification of Deviation:

Loss of a second fan on the "C" Cool'ing Tower and removal of the "A" Cooling Tower 1ift pump from service. Both the. fan and *.he lift pump are in' service.as of this writing.

l Conditions Prior to Deviation:

Unit 2 operating at approximately 35% power. Unit 3 shutdown.

, Description of Deviation:

1.

The "B" fan motor breaker tripped making this the second in-operabic fan on the "C" Cooling Tower.

During calibration of a pump suction screen differential -

. pressure device,- it was noted that a section of ins trument standpipe had broken at the water level. A section of 4 inch diameter pipe, i about 15 feet long fell into the lif t pump suction bay. The lift pump was removed from service to protect it from potential damage.

8401260350 750203 PDR ADOCK 05000277 S PDR

~1 Mr. A. Giambusso  %.) (V Februzry 3, 1975 ,

Page 2 Designation of Apparent Cause of Deviation:

Investigation revealed that the fan motor had tripped on high vibration.

The standpipe is free-standing and not braced either hori-zontally or vertically, and is in the water flow path to the suction of the pump. The failure is attributed to the flow induced forces and vibration aggravated by low temperaturcs.

Analysis of the Deviation:

The "B" F an was out of service a short time and did not cause a change in the temperature of the water discharged from the tower.

While the missing piece of pipe was being located and removed, additional data on river flows and temperatures was taken at the request of the Pennsylvania Department of Environmental Resources. The relatively low plant power output, high river flows and negligible temperature changes resulted in insignificant impact on the environment.

Corrective Action:

The fan vibration trips were reset and the fan has ope ated satisfactorily since being restarted. A diver was used to locate and re.r.ove tne missing section or pipe from the pump suction bay and the li f t pump was returned to service.

Qilure Data:

Environmental Deviation Report Number 50-277/278-74-2 (fan motor).

Very truly yours, M

M. J. Cooney A s't Gen' t Superintendent Generation Division cc: Mr. J. P. O'Reilly, Director Office of Inspection and Enforcement Region 1 United States Nuclear Regulatory Comission ,

631 Park Avenue King of Prussia, PA 19406 1

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