ML20090C449

AO-75-031:on 751114,both Radiation Monitors in Reactor Bldg Ventilation Duct Failed to Provide Transfer to Emergency Ventilation Sys at 5 M/H.Caused by Incorrect Adjustment Made Prior to Calibr

ML20090C449
Person / Time
Site:	Nine Mile Point
Issue date:	11/26/1975
From:	Schneider R NIAGARA MOHAWK POWER CORP.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20090C453	List: ML20090C449 ML20090C455
References
13538, 13949, AO-75-031, AO-75-31, NUDOCS 8302180076
Download: ML20090C449 (3)

Text

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NIAGARA MOHAWK POWER CCRPORATION I

NIAGARA MOHAWK i-I' DATE: November 26, 1975 c

SUBJECT:

Abnormal Occurrence Report No. 50 220 75 31 (10 Day Letter) ..

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The enclosed Abnormal Occurrence Report is being submitted in i

accordance with Technical Specificat.on .Section 6. -

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TO: James P. O'Reilly _

Directorate of Regulatory Operations .

Region 1 /

631 Park Avenue ,

King of Prussia, Pa. 19406 FROM: Niagara Mohawk Power Corporation '

Nine Mile Point - James A. FitzPatrick Site -

P.O. Box #32 Lycoming, New York 13093 Docket No. 50- 220 .

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REFERENCE:

License DPR- 63

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Report No.: 50- 220/75- 31 Report Date: 11/26/75 Occurrence Date: 11/14/75 Facility: NY NMP #1 Identification of Occurrence:

Failure of both radiation monitors located in the Reactor Building l-

! Ventilation Duct to provide a transfer to Emergency Ventilation System l at 5 mr/hr. . ,

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8302100076 751126 ,

PDR ADOCK 05000220 l S PDR

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AOR 75-31 N '

/3 Conditions Pricr to D

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Occurrence: Steady State Power ' Routine Shutdown l- ,

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Hot Standby-Cold Shutdown. Load Changes

- X -Refueling Shutdown Routine Startup ' Other i

- Description of the Occurrence:

e Durin'g routine radiation protection surveillance testing, both l

radiation monitors in the Reactor Building Ventilation Duct fail'ed to provide

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l - transfer to kmergency Ventilation System until 20 mr/hr and 30 mr/hr resfectively-was applied to the sensors. The cicetronic calibration had just previously been performed. -

j. 5 Apparent Cause o'f the Occurrence:

Design X Procedure l

l Manufacture Unu,sual Service Condition Installation / -

' Const.

X Operator Component Failure Other (Specify) ,

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l Analysis of Occurrence:

During refueling operation, the radiation monitor' located on the refueling platform will also cause a tran.fer to Emergsney Ventilation. The plant has been in refueling since September 11, 1975. Thus protection for the public was adequately supplied by this monitor in the event of a dropped fuel assembly.

P orrective Action:

i , The investigation revealed that an inadvertant adjustment was made to these instruments prior to their calibration. Better coordination be-tween the verification of trip point and the electronic alignment will be implemented, and should prevent this in the future. Additional administra-

=, tive controls,wil.1 be imposed for this type of calibration.

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Failure Data: '

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G,, '3 NIAGARA' MOHAWK POWER CORPORATION rj iN

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bit. James P. O'Reitig Directorate of Regulatory,0perations 8 *

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Region I /S. f t United States Nuctcar Regulato.tt) Connission i (f f p.fj 631 Park Avenue King of Prussia, Pa. 19406

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RE: Docket No. 50-220 _

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Dear blt. O'Reitty:

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9 Enclosed ptcase find Abnormat OccurtencE Rep &tts 75-31 and 75-32 for Nine Ilite Poin.t Nuclear Plant Unit., #1. The.se reports:are submi.ited

., in accordance with Regulatory Guide 1.16 and constitute fhtfittment of the fifteen (15) day lettet requirements. The Licensee Event Reports forms Q be submitted by the 10th of December,1975. ,

Very truly yours,

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ML f'

" R.R.-Schneid w -

Vice President ' ';  ;

Electric Operations

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