United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for December 28, 2001

                       Headquarters Daily Report

                         DECEMBER 28, 2001

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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  DEC. 28, 2001

Licensee/Facility:                     Notification:

Southern Nuclear Operating Company     MR Number: 2-01-0020
Hatch 1 2                              Date: 12/28/01
Baxley,Georgia
Dockets: 50-321,50-366
BWR/GE-4,BWR/GE-4

Subject: UNIT 2 REACTOR SCRAM

Discussion:

Reference Event Number:  38592

On December 25, 2001, Unit 2 automatically scrammed due to high neutron
flux.  The licensee initially attributed the cause of the scram to a
speed increase of the 2A Reactor Recirculation Pump.

On December 26, 2001, after reviewing additional data the licensee
determined that a rapid steam flow reduction in the 'B' steam line
resulted in a Reactor Pressure Vessel pressure increase.  The licensee
conducted testing of the 'B' steam line and determined that the Outboard
Main Steam Isolation Valve disc had separated from the stem.  The
resulting pressure increase due to the MSIV failure cause in a positive
reactivity insertion due to void collapse causing the reactor to scram.
The licensee is in the process of evaluating the cause of the stem
failure and has planned a 94 hour forced outage to repair the valve.

Regional Action:

None.

Contact:  Curt Rapp                  (404)562-4674
          Joel Munday                (912)367-9881
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