05000327/LER-1981-026-01, /01T-0:on 810310,analysis of Primary Containment Airlock Electrical Penetrations Revealed Probable Leak Paths Under Accident Conditions.Caused by Design Failure to Evaluate Sealing Matl.New Cables,Conduits & Seals Ordered

/01T-0:on 810310,analysis of Primary Containment Airlock Electrical Penetrations Revealed Probable Leak Paths Under Accident Conditions.Caused by Design Failure to Evaluate Sealing Matl.New Cables,Conduits & Seals Ordered

ML19343C802
Person / Time
Site:	Sequoyah
Issue date:	03/18/1981
From:	Maddox S, Mcgriff J TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19343C798	List: 05000327/LER-1981-026, Forwards LER 81-026/01T-0 05000327/LER-1981-026-01, /01T-0:on 810310,analysis of Primary Containment Airlock Electrical Penetrations Revealed Probable Leak Paths Under Accident Conditions.Caused by Design Failure to Evaluate Sealing Matl.New Cables,Conduits & Seals Ordered
References
LER-81-026-01T, LER-81-26-1T, NUDOCS 8103250306
Download: ML19343C802 (2)

LER-1981-026, /01T-0:on 810310,analysis of Primary Containment Airlock Electrical Penetrations Revealed Probable Leak Paths Under Accident Conditions.Caused by Design Failure to Evaluate Sealing Matl.New Cables,Conduits & Seals Ordered

Event date:
Report date:
3271981026R01 - NRC Website

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PART 21 REPORT NCR SQNEEB8108 i

LER SQRO-50-327/81026 Originating Document No. PRO l-81-055 Plant Seouovah Nuclear Plant, Unit 1 i

Component or System Identification Primary containe.ent airlock electrical penetrations Supplier of Component Nature of Defect or Noncompliance Ekch oersonnel airlock has two (2) 1" and one (1) 2" conduits that are nealed with chico A comoound in an EYS explosion-proof seal-ing condulet or RTV silicone rubber in a "C" or "L" type condulet. These materials will not maintain a seal against steam pressure.

Extent of Safety llazard Failure could cause leak rate of entire containment to exceed the value allowed by 10 CFR 50 and/or cause radiation release to exceed that allowed by 10 CFR 100.

Date Which Defect or Noncompliance Was Discovered 3/10/81 Number of Identical Components in Use 6 (4-1", 2-2") per unit Location of Components Personnel airlocks at elevation 734 and 690 t

l Corrective Action Taken or To Be Taken Interim corrective action-cables were re-i

- moved, conduits stubbed at airlocks, caps installed on conduits, and leak tested.

Permanent design change will install new conduit, cable and qualified sealing material.

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Interim corrective actions have been Length of Time Required to Complete Action accomolished and verified by a satisfactory leak rate test. The permanent modi-fications will be accomplished during outages.

- Has defect or noncompliance been reported previously? Yes No X

If yes, by what means?

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