United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for April 15, 1999

                       Headquarters Daily Report

                         APRIL 15, 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 II  APRIL 15, 1999

Licensee/Facility:                     Notification:

Tennessee Valley Authority             MR Number: 2-99-0009
Watts Bar 1                            Date: 04/15/99
Spring City,Tennessee
Dockets: 50-390
PWR/W-4-LP

Subject: MANUAL REACTOR TRIP DURING REACTIVITY CONTROL SYSTEM TESTING
         (REPORTABLE EVENT NO. 35573)


Discussion:

On April 11, 1999 at 00:42 a.m., Unit 1 experienced a continued outward
control rod motion for shutdown bank A upon release of the rod control
switch.  This problem occurred during pre-startup control rod testing
following the refueling outage. The operator appropriately opened the
reactor trip breakers and all shutdown bank a control rods fully inserted
as expected. All other control rods were fully inserted at the time that
shutdown bank A was being tested. Reactor coolant system boron
concentration was at 2184 ppm with the unit in Mode 3 at normal operating
temperature and pressure.

Subsequent troubleshooting identified a defective logic control card in
the master cycler. The logic control card was replaced and pre-startup
control rod testing was completed satisfactory with no additional
problems.

The resident inspectors have been following licensee troubleshooting and
corrective actions activities. The licensee is planning to return the
defective logic control card to the vendor (Westinghouse) for a detailed
failure analysis.

Currently the unit is operating at 14 percent power, conducting
post-startup tests prior to resuming full power operation.

Contact:  PETER TAYLOR               (404)562-4562
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