United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for August 24, 1999

                       Headquarters Daily Report

                         AUGUST 24, 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 III  AUGUST 24, 1999

Licensee/Facility:                     Notification:

Commonwealth Edison Co.                MR Number: 3-99-0074
La Salle 2                             Date: 08/22/99
Marseilles,Illinois                    Licensee report/Resident call 8/23
Dockets: 50-374
BWR/GE-5

Subject: Automatic Shutdown on Low Reactor Water Level

Discussion:

At 22:00 on 8/21/99 Unit 2 operators commenced a load drop to repair a
degraded condition on the main generator phase A potential transformer.
At 22:55 with the reactor at 78 percent power, the reactor scrammed
automatically due to low reactor level induced by a feedwater level
transient. All control rods fully inserted. Reactor level and pressure
followed expected trends. All systems responded as expected. Subsequent
to the scram, minor problems were encountered putting the main turbine
and the "A" turbine driven feed pump on their respective turning gear.
The licensee's preliminary investigation of the event has determined two
causes for the scram. First, was inadequate testing and tuning of the
feedwater control system at this power level. The licensee plans to
conduct further feedwater system testing and tuning during the return to
full power. Second, the operator did not perform the expected procedural
actions in response to the event. The licensee is continuing to determine
the potential extent of condition and corrective actions.

Regional Action:

The senior resident inspector responded to the site and is monitoring the
licensee's post scram investigation and corrective actions.

Contact:  Melvyn Leach               (630)829-9705
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REGION III  MORNING REPORT     PAGE  2          AUGUST 24, 1999

Licensee/Facility:                     Notification:

Commonwealth Edison Co.                MR Number: 3-99-0075
La Salle 2                             Date: 08/22/99
Marseilles,Illinois                    Licensee report, 8/23/99 R.I. call
Dockets: 50-374
BWR/GE-5

Subject: Automatic Shutdown on Low Reactor Water Level
Reportable Event Number: 36056

Discussion:

At 22:00 on 8/21/99 Unit 2 operators commenced a load drop to repair a
degraded condition on the main generator phase A potential transformer.
At 22:55 with the reactor at 78 percent power, the reactor scrammed
automatically due to low reactor level induced by a feedwater level
transient. All control rods fully inserted. Reactor level and pressure
followed expected trends. All systems responded as expected. Subsequent
to the scram, minor problems were encountered putting the main turbine
and the "A" turbine driven feed pump on their respective turning gear.

The licensee's preliminary investigation of the event has determined two
causes for the scram. First, was inadequate testing and tuning of the
feedwater control system at this power level. The licensee plans to
conduct further feedwater system testing and tuning during the return to
full power. Second, the operator did not perform the expected procedural
actions in response to the event. The licensee is continuing to determine
the potential extent of condition and corrective actions.

Regional Action:

The senior resident inspector responded to the site and is monitoring the
licensee's post scram investigation and corrective actions.

Contact:  Melvyn Leach               (630)829-9705
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