United States Nuclear Regulatory Commission - Protecting People and the Environment

Accession No. 9508240355

                         EVENT NOTIFICATION WORKSHEET

Notification Time:  18 Aug 1995 1352

Facility:           Watts Bar Unit 1, 2

Caller's Name:      P. L. Pace

Caller's Number:         (615) 365-1824

Event Date:         16 August 1995

Regulation:         10 CFR 50.55(e)

Description:        Finding Identification Report (FIR) WBFIR930012307 was initiated, in
part, to document potential deficiencies associated with uninspected vendor wired safety-related
electrical panels.  As part of the corrective actions to resolve the FIR condition, walkdowns of
previously uninspected vendor wired safety-related electrical panels were to be performed. 
Those walkdowns have been completed.  A review of work implementing documents generated
to resolve deficiencies identified during the FIR walkdowns revealed four categories of
deficiencies:  (1) terminal blocks; (2) loose connections; (3) cables/conductors; and (4)
cable/conductor insulation gaps.  Category 1, 3, and 4 deficiencies have been evaluated as not
having an adverse impact on plant safety.  However, the Category 2 loose connections could
have had an adverse affect on plant safety.  The loose connections involve both the termination
of incoming field cables as well as vendor terminations.  Although some of this number could
involve nonsafety-related circuits fed from the safety-related board/panel, a significant portion of
the loose connections have been confirmed to be associated with saety-related circuits in various
safety-related systems (e.g. Component Cooling System, Safety Injection System, Ventilating
System, Essential Raw Cooling Water System, Residual Heat Removal System, etc.) and involve
redundant divisions of safety-related circuits.  During a seismic event, the loose connections
must be assumed to create an open circuit.  The resulting condition may place the plant in an
indeterminate condition.

Reference:  WBFIR 930012 307
            CDR 50-390, 391/95-05
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