United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for August 13, 1999

                       Headquarters Daily Report

                         AUGUST 13, 1999

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                    REPORT             NEGATIVE            NO INPUT
                    ATTACHED           INPUT RECEIVED      RECEIVED

HEADQUARTERS                           X
REGION I            X
REGION II                              X
REGION III                             X
REGION IV                              X
PRIORITY ATTENTION REQUIRED  MORNING REPORT - REGION I  AUGUST 13, 1999

Licensee/Facility:                     Notification:

New York Power Authority               MR Number: 1-99-0029
Indian Point 3                         Date: 08/13/99
Buchanan,New York
Dockets: 50-286
PWR/W-4-LP

Subject: SUPPLEMENTAL REACTOR TRIP INFORMATION
Reportable Event Number: 36023

Discussion:

At approximately 4:05 a.m. on August 12, 1999, the Indian Point-3 reactor
tripped on low steam generator level following a loss of main feedwater
and a turbine runback that resulted from the loss of one instrument bus.
A blown fuse in the static inverter to the 34 instrument bus caused the
bus to de-energize, which removed control power to all feedwater
regulating valves causing them to fail closed.  The bus does not have an
automatic transfer to an alternate power supply.  Following the reactor
trip, one pressurizer power-operated relief valve and one steam generator
safety relief valve lifted.  In addition, the instrument bus loss
resulted in the loss of the high pressure main steam dumps and two of
four steam generator atmospheric relief valves.

Secondary heat removal was provided by the remaining steam generator
atmospheric relief valves.  At approximately 5:05 a.m. and again at 5:45
a.m. the 32 steam generator safety valve lifted again and reseated at the
appropriate setpoints.

The instrument bus was placed on the alternate power supply after
approximately 1-1/2 hours and the main steam dumps were restored as the
means for secondary heat removal.  The licensee is evaluating the causes
of the instrument bus failure, the subsequent plant transient, and
operator performance following the reactor trip.

Regional Action:

Continue to monitor licensee's review.

Contact:  John Rogge                 (610)337-5146
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