Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
ACCESSION #: 9705210401
NSD-NRC-97-5093
Westinghouse Energy Systems Nuclear Services Division
Electric Corporation
Box 355
Pittsburgh, Pennsylvania 15230-
0355
May 14, 1997
U.S. Nuclear Regulatory Commission
ATTN: Document Control Desk
Washington, DC 20555-0001
Attention: NRC Operations Center
Subject: Notification of the Potential Existence of Defects Pursuant to
10CFR21.21
Westinghouse has identified defects that could create a substantial
safety hazard should the defect remain uncorrected.
Background/Evaluation
Deviations were identified by Westinghouse during a lessons learned
review of a pilot program to provide safety-related circuit breaker
refurbishment for the Byron/Braidwood Nuclear Station sites. The
refurbishment pilot program included both Westinghouse Type DHP Series
and DS Series breakers. The pilot program was conducted at Westinghouse
satellite facilities and failed to utilize correct procedures which
resulted in certain tests and inspections not being performed or
documented. The items which were omitted or not documented included the
performance of timing tests, contact resistance checks to correct values,
reapplication of lubricant, opening force margin verification, and weld
inspections. These tests and inspections are designed to provide
assurance that breaker operation, either to open or close, will be
successfully completed. W determined that the tests that were performed
on the refurbished breakers before their return to Byron/Braidwood were
insufficient to reestablish full qualification of the breakers.
Safety Significance
The DHP and DS circuit breakers are used in applications such as SI
pumps, RHR pumps, fan coolers and vent fans. Although unlikely,
installation of breakers that are not fully qualified in redundant trains
could result in the inability to perform a safety function on demand.
Since the Westinghouse data from the pilot program was considered
insufficient, the utility was contacted to collect the operational
history of each breaker after refurbishment to provide reasonable
assurance of operability. Based on the utility provided data and the
fact that the breakers were refurbished at Westinghouse's facilities
under controlled conditions by competent personnel, it was determined
that the breakers would be operable in the short term. Additional
cycling was performed on some refurbished breakers to provide confidence
that the breakers would remain operable until proper refurbishment could
he completed.
"The mission of NSD is to provide our customers with people,
equipment and services that set the standards of excellence in the
nuclear industry"
2418C-RBM-1:051297
NSD-NRC-97-5093 2 May 14, 1997
The only plants involved in the pilot program were Byron and Braidwood
Nuclear Stations. The population of affected applications is limited to
twelve DHP and twelve DS breakers which were returned to the Braidwood
site and two DS breakers which were returned to the Byron site.
Recommendations/Corrective Action
All of the breakers that were refurbished using incorrect procedures have
been identified. Personnel from each applicable plant have been notified
and have confirmed operability of the breakers. As corrective actions,
approved Procedures at Westinghouse's satellite facilities have been
developed for the continued refurbishment of both DHP and DS breakers to
preclude the reoccurrence of this situation. Plans to complete the
proper refurbishment of all of the returned breakers are being
established.
If you have any questions regarding the notifications, please call me at
(412) 374-5282.
Very truly yours,
H. A. Sepp, Manager
Regulatory and Licensing Engineering
/p
2418C-RBM-2:051297
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