05000321/LER-1979-089-01, /01T-0:on 791106,A/E Discovered Portions of RHR Containment Spray Line,Reactor Head Vent Line & Main Steam Bypass to Condenser Valve Chest Not Seismically Supported. Caused by Deficiencies in Original Design & Deviations

/01T-0:on 791106,A/E Discovered Portions of RHR Containment Spray Line,Reactor Head Vent Line & Main Steam Bypass to Condenser Valve Chest Not Seismically Supported. Caused by Deficiencies in Original Design & Deviations

ML19256F127
Person / Time
Site:	Hatch
Issue date:	11/16/1979
From:	Coggin C GEORGIA POWER CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19256F125	List: 05000321/LER-1979-089, Forwards LER 79-089/01T-0 05000321/LER-1979-089-01, /01T-0:on 791106,A/E Discovered Portions of RHR Containment Spray Line,Reactor Head Vent Line & Main Steam Bypass to Condenser Valve Chest Not Seismically Supported. Caused by Deficiencies in Original Design & Deviations
References
LER-79-089-01T, NUDOCS 7911210456
Download: ML19256F127 (3)

LER-1979-089, /01T-0:on 791106,A/E Discovered Portions of RHR Containment Spray Line,Reactor Head Vent Line & Main Steam Bypass to Condenser Valve Chest Not Seismically Supported. Caused by Deficiencies in Original Design & Deviations

Event date:
Report date:
3211979089R01 - NRC Website

text

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EVENT OATE 74 7b HEPOHT DATE 60 EVENT DESCRIPiloN AND PROB ABLE CONSEQUENCES lWhile evaluating as-bu;1t seismic piping and supports, per IE Bulletin 79-14, it was g

l o 12 j discovered by the A/E that portions of the RHR containment spray line, the reactor gi g o p l l head vent line, and the main steam bypass to condenser valve chest are not supported l I seismic Class 1.

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Georgia Power Company Plant E. I. Ilatch Baxley, Georgia 31513 Event Description and Probable Consequencesshutdown, nor would it pose any threat to public health or safety. This is a non-repetitive occurrence.

Cause Description and Corrective Actions (cor.tinued) portion is awaiting both design and implementation.

13/6

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Narrative

Report While evaluating as-built seismic piping and supports, per IE Bulletin 79-14, it was discovered by the A/E that several portions of different systems were not supported seismic class 1.

These include:

a portion of RHR head spray piping near valve E11-F028; the main steam bypass to condenser valve chest; and the head vent line near valves B21-F003 and F004.

The RHR line supports have been modified to seismic specifications under DCR 79-423 and, therefore, are no longer considered a problem. The deficiencies in the RHR piping supports were identified and corrected prior to the A/E deem-ing the deficiency reportable. The bypass valve chest supports pose no major problem because this valve chest is downstream from both MSIVs and would be automatically isolated in the event of a pipe break.

A design modification has been generated by the A/E and will be implemented during the next cold shutdown.

The head vent line is inside the primary containment.

A line break in this area would be isolated from the reactor building.

A break in this two-inch line would not interfere with a safe reactor shutdown.

The A/E is in the process of generating a design modification for the head vent line which will be implemented during the next cold shutdown.

In addition, the occurrence of any of the above scenarids is highly unlikely due to the extremely low probability of a design basis seismic event.

The causes of this event were deficiencies in the original design and field deviations from the original design.

No releases of radioactivity or hann to personnel resulted from this event, nor was there any threat to public health or safety.

13/6 5i1