ML20113B872

Ro:On 850308,peak Acceleration Recorder Declared Inoperable Following Insp.Caused by Melting of Mounting Matl Used to Support Recorder Due to High Temp Inside Drywell Head Area.Recorder Replaced

ML20113B872
Person / Time
Site:	Limerick
Issue date:	03/18/1985
From:	Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Murley T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
NUDOCS 8504110446
Download: ML20113B872 (3)

Text

r PHILADELPHIA ELECTRIC COMPANY 23of MARKET STREET P.O. BOX 8699 PHILADELPHIA, PA.19101 (215)841-4000 March 18, 1985 Docket No. 50-352 Dr. Thomas E. Murley Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406

SUBJECT:

Special Reporting Requirement - Seismic Monitoring Instrumentation Inoperable for More Than 30 Days - Limerick Generating Station Unit 1

REFERENCE:

Technical Specifications 3.3.7.2 and 6.9.2

Dear Dr. Murley:

In accordance with the Limerick Generating Station subject Technical Specification reporting requirements, Philadelphia Electric Company is reporting that the peak acceleration recorder (XR-VA-151) located at the top of the reactor vessel head has been inoperable in excess of 30 days.

! The instrument was declared inoperable following an inspection on March 8, 1985.

I i

i Cause:

The mounting material used to_ support the recorder was inadequate due to high temperatures occurring inside the drywell head area.

Significant melting of this substance occurred, causing a shift in position of the unit. In addition, heat damage to internal components of the recording device was evident. These conditions, in conjunction with a loss of mounting integrity, i

would have precluded accurate data acquisition in the event of a seismic occurrence.

8504110446 850318 1 i . PDR ADOCK 05000352 1 l

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Dr. Thomas E. Murley March 18, 1985 Page 2 i The cause of the high temperatures in the drywell head area was i ' lack of insulation on the RHR head spray line in the area of the drywell where this line enters the reactor vessel head. XR-VA-151 is mounted on this line.

Corrective Actions:

The following corrective measures are being' implemented:

1) Replacement of the peak acceleration recorder.

i 2) Insulation of the recorder mounting bracket and RHR head spray piping adjacent to the device.

3) Insulation of the head' spray line-to-vessel head flange.

This work is scheduled to be completed prior to the end of the.

I current outage. These corrective measures will prevent recurrence of this event.

4

, Should-you require additional information, please do not 4

hesitate to contact us.

Very truly yours, W...T. Ullrich e Superintendent.

i Nuclear Generation Division l 1

4 cc:: J.=T. Wiggins,' Senior Site Inspector See-Attached Service List i

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cc: Judge Helen F. Hoyt Judge Jerry Harbour Judge Richard F. Cole Troy B. Conner, Jr., Esq.

Ann P. Ilodgdon, Esq.

Mr. Frank R. Romano Mr. Robert L. Anthony Ms. Phyllis Zitzer Charles W. Elliott, Esq.

Zori G. Ferkin, Esq.

Mr. Thomas Gerusky Director, Penna. Energency Management Agency Angus Love, Esq. -

David Wersan, Esq.

Robert J. Sugannan, Esq.

Martha W. Bush, Esq.

Spence W. Perry, Esq.

Jay M. Gutierrez, Esq.

Atomic Safety G Licensing Appeal Board Atomic Safety 6 Licensing Board Panel Docket 4 Service Section James Wiggins Timothy R. S. Campbell de L___ - -