ML19341D718

Forwards LER 81-019/01T-0.Vent Monitors Could Become Inoperable If Walls Collapsed During Seismic Event

ML19341D718
Person / Time
Site:	Peach Bottom
Issue date:	04/03/1981
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Grier R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19341D719	List: ML19341D718 ML19341D720
References
NUDOCS 8104080488
Download: ML19341D718 (2)

Text

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i C q .O 9 A PHILADELPHIA ELECTRIC COMPANY 2301 M ARKET STREET I

. fj P.O. BOX 8699 y

1881 -1901 PHILADELPHI A. PA.19101 1

., 12151 841 40o0

'l April '3, 1981

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( ' 4 Pr. Bo yce H. Grier, Director 'M

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Of fice of Inspt: tion and En fo rc em en t Region I r

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U.S. Nuclear Regulatory Commission \cd '*',,qh (l' 631 Park Avenue ,

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j King o f Prussia , PA 19406 .3,.

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Dear Mr. Grier:

I

SUBJECT:

Licensee Event Recort Narrative Descriotion The following occurrenca was reported to Mr. C. Co wg ill ,

Region f, Office of Inspection and Enforcement on March 20 1991

Reference:

Cocket Number 50-277/278 t

Report No.: LER 2-81-10 /1T-0 #

Report Date

April 3, ly31 Occurrence Date: March 20, 1981 Facility: Peach Bottom Atomic Power Station RD #1, Delta, PA 1731u i

Technical Soecification

Reference:

Technical Specification 1.8.C.8 states in part that "One reactor building exhaust vent... monitoring system shall be opernbla or operating whenever steam pressure is available to the air ej ectors ."

Descriotion of the Event

During re-evaluation of concrete block walls as requirad by

I.E. Bulletin 80-11, " Masonr y '4all Design", walls 102.1 and 102.9 (Unit 2) and walls 418.10 and 418.11 (IJnit ?) were found to be unstable under the effects of an Operating Basis Earthquake (0.B.0.) .

These walls are located on the rafueling floor adj acent to the vent

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80040 80 %%B jf w.

Mr. Bo yce H. Grier, Director Page 2 April 3, 1931 LER 2-81-19/1T-0 l

stack radiation monitors and the conduit associated with these monitors.

Probable Consequences of the Occurrence The vent monitors could become inoperable should th e wa l l s collapse during a seismic event . Technical Specifiention 1.8.C.8 requires that in the event of loss o f the vent stack radiation monitors a shutdown shall be initiated within one hour, and that the plant be in hot shutdown within 10 days. The monitors have remained operable since the event was reported and they do not function in the safety system logic. Modifications to the affected walls of the e- operating unit have been completed. Additionally, in the event of a7 0.B.E. the plant would be shutdown for other reasons related to the event.

Cause of the Event Cause of event was construction or design error.

Corrective Actions

]q On March 30, 1981, modifications were completed to Unit P walls '102.8 and 102.9 to assure adequacy of the walls to withstand a

-j Design Basis Earthquake. Similar modifications will be completed on Unit 3 prior to completion of the current refueling outage.

Very truly yours ,

al~

f- /GC%CA%f

.. Cooney /

Su /rintendent GeKeration Division / Nuclear Attachment-

!j-cc: . Director, NRC - Office of Inspection and Enforcement Mr . No rm an M. Haller, NRC - Office of Management &

Program Analysis f

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