05000278/LER-1981-014, Forwards LER 81-014/01T-0.Detailed Event Analysis Submitted

Forwards LER 81-014/01T-0.Detailed Event Analysis Submitted

ML20011A683
Person / Time
Site:	Peach Bottom
Issue date:	10/13/1981
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20011A684	List: 05000278/LER-1981-014, Forwards LER 81-014/01T-0.Detailed Event Analysis Submitted 05000278/LER-1981-014-01, /01T-0:on 810928,while in Cold Shutdown Condition W/Crd Sys Off to Support Plant Testing,Problems Were Encountered in Maintaining Vessel Level.Caused by Personnel Error & Incomplete Closure of Feedwater Stop Valve
References
NUDOCS 8110290283
Download: ML20011A683 (3)

LER-1981-014, Forwards LER 81-014/01T-0.Detailed Event Analysis Submitted

Event date:
Report date:
2781981014R00 - NRC Website

text

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PHILADELPHIA ELECTRIC COMPANY 23O1 MARKET STREET P.O. BOX 8699 1881 -1981 PHILADELPHIA. PA.19101 M

(215 8414000 g\\p' ' '

October 13, 1981

? ocr2 8 ws, Ea

'IoT4,j@mn Mr.

R.

C.

Haynes, Director

\\

d' Office of Inspection and Enforcement g's Region I U.S. Nuclear Regulatory Commission C)

P 631 Park Avenue King of Prussia, PA 19406

SUBJECT:

Licensee Event Report Narrative Description

Dear Mr. Haynes:

The following occurrence was reported to Mr.

C.

Cowgill, Region I, Office of Inspection and Enforcement on. September 28, 1981.

Reference:

Docket Nos. 50-278 Report No.:

LER 3-81-14/1T-0 Report Date:

October 13, 1981 Occurrence Date:

September 28, 1981 Facility:

Peach Bottom Atomic Power Station RD #1, Delta, PA 17314 Technical Specification Reference:

f Technical Specification 3.7.A.1 states in part that "Whenever the nuclear system is pressurized above atmospheric the pressure suppression pool water volume pressure.

.shall be maintained within the following limits.

3 b.

Maximum water volume - 127,300 ft "

Technical Specification 4.6.A.2 states in part that

" Reactor vessel temperature and reactor coolant pressure shall be permanently logged at least every 15 ninutes whenever the shell temperature is below 220 F and the reactor vessel is not vented."

8110290283 811013 g_ f,jb '

yDRADOCK 05000278 7

PDR cI l

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Mr. R. C. Hnyn0, Dircctor Pags 2 Detailed Description of the Event While in cold condition with the reactor shutdown for refueling, difficulty in maintaining reactor level was encountered when the Control Rod Drive water system was removed from service to support plant testing.

Vessel level decreased to about 60 inches.

A feedwater inlet valve was then opened slightly to supply makeup water to the vessel.

Vessel level was recovered to 90 inches and the feedwater valve was closed.

Leakage through the valve occurred and level increased above the main steam line nozzles.

As a result of the loss of the reactor vent path (main steam lines to condenser), the reactor pressurized to about 32 psig for about 35 minutes.

To decrease vessel level, water was transferred from the vessel to the torus.

This increased torus level 0.15 feet above Technical Specification maximum.

The torus water cleanup pump was placed in service at this time.

The Technical Specification 4.6.A.2 requirement to log reactor vessel temperature and pressure was overlooked, however, installed plant instrumentation recorded this data.

Later, during an attempt to obtain a tight shutoff of the feedwater inlet valve, the reactor was again pressurized to about 78 psig for 30 minutes.

The reactor head vent valves were opened to depressurize the vessel.

A tight shutoff was obtained on the feedwater valve and level control was achieved by using the RWCU system.

Although the Technical Specifications do not specifically preclude operation under the temperature and pressure conditions which occurred during this event, we believe they were meant to do so and are reporting this item as such.

Probable Consequences of the Occurrence The reactor remained in the cold condition during both pressurizations.

Pressurization of the vessel occurred at a temperature which was not significantly below the 120 F limit.

Additionally, primary containment integrity was not required during the occurrence.

Therefore, the reduction in suppression chamber free volume, approximately 0.65 percent, was not significant.

Cause of Occurrence Operator failed to reeognize that he was losing primary system inventory when the CRD water system was removed from service.

Incomplete closure of the feedwater inlet valve MO-3 29B after supplying make-up wate caused level to increase above main steam line nozzles.

. Mr.

R.

C. Haynoc, Director Pegn 3

Immediate Corrective Actions

The torus water cleanup pump was placed in service to restore proper torus' level.

The reactor head vent valves were opened to depressurize the vessel to atmospheric pressure and - a tight shut was obtained on the feedwater~ inlet valve.

4 Operators were counseled on the importance of

. recognizing and monitoring those parameters which affect vessel level.

4 Actions Taken to Prevent Reoccurrence The operational aspects of this occurrence are under review to determine any appropriate further actions.

Very truly yours,

/

3 i.

M.e J. Cooney Sdperintendent Generation Division - Nuclear cc:

Director, NRC - Office of Inspection and Enforcement Mr. Norman M. Haller, NRC - Office of Management &

Program Analysis

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