Morning Report for September 19, 2002

                       Headquarters Daily Report

                         SEPTEMBER 19, 2002

                    REPORT             NEGATIVE
                    ATTACHED           INPUT RECEIVED

HEADQUARTERS                           X
REGION I                               X
REGION II                              X
REGION III                             X
REGION IV           X


Licensee/Facility:                     Notification:

Entergy Operations, Inc.               MR Number: 4-02-0002
River Bend 1                           Date: 09/19/02
St Francisville,Louisiana              Licensee to SRI on 9/18
Dockets: 50-458

Reportable Event Number: 39200


At approximately 8:24 p.m. on September 18, 2002, the River Bend Station
scrammed from 100 percent reactor power due to a high average power range
monitor flux trip.  All control rods fully inserted in the core.  The
cause of the reactor trip is currently under investigation.  Preliminary
evidence indicates that a failure of the electrohydraulic control system,
resulting in rapid cycling of the turbine generator bypass valves, may
have been the cause for the high power scram.

Following the scram, both steam jet air ejector condensers experienced
gasket failures on the end bells of the condensers, and all reactor feed
pumps tripped on low suction pressure.  Operators responded to the
condensate system gasket failure by securing all condensate pumps and
manually isolating the steam jet air ejector condensers.  With the loss
of condensate to the reactor vessel, operators manually initiated the
reactor core isolation cooling system to maintain the appropriate reactor
level and remove decay heat.

Upon securing the condensate pumps, the control rod drive pumps
automatically aligned suction to the condensate storage tank.  Following
this transfer, alarms in the control room indicated high differential
pressure conditions on the control rod drive pump's suction and discharge
filters.  Operators bypassed the filters and were able to regain flow.
The licensee currently believes the high differential pressure condition
was a result of particulate in the condensate storage tank being
collected in the control rod drive system filters.

The licensee currently believes the transient causing the steam jet air
ejector condenser gasket failure and loss of feed pump suction pressure
were both initiated as a result of an inadvertent closure of the
condensate full flow filter bypass valve following the scram.

Using the reactor core isolation cooling system and the control rod drive
pumps, the operators have continued to maintain the reactor in a stable
hot standby condition.

The licensee continues to investigate the cause of the reactor trip, the
failure of the steam jet air ejector condienser gaskets, and the
inadvertent closure of the condensate full flow filter bypass valve.

Regional Action:

In response to this event, NRC resident inspectors responded to the
licensee's control room.  They continue to monitor licensee activities.
REGION IV  MORNING REPORT     PAGE  2          SEP. 19, 2002
MR Number: 4-02-0002 (cont.)

Contact:  R. Kopriva                 (817)860-8104
          P. Alter                   (225)635-3193


Page Last Reviewed/Updated Wednesday, March 24, 2021