United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for January 19, 2000

                       Headquarters Daily Report

                         JANUARY 19, 2000

***************************************************************************
                    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  JANUARY 19, 2000

Licensee/Facility:                     Notification:

Tennessee Valley Authority             MR Number: 2-00-0003
Sequoyah 1 2                           Date: 01/19/00
Soddy-Daisy,Tennessee
Dockets: 50-327,50-328
PWR/W-4-LP,PWR/W-4-LP

Subject: UNIT 2 INADVERTENT SAFETY INJECTION AND REACTOR TRIP

Discussion:

On January 18, 2000, at 10:51 a.m., while Unit 2 was operating at 100
percent power, an engineered safety feature actuation (ESF) signal
occurred resulting in an automatic reactor trip and safety injection into
the reactor coolant system (RCS) from train "A" only.  The ESF actuation
signal occurred while modifications where in progress on vital inverter
2-IV and technicians were lifting electrical wiring.  The licensee has
initiated troubleshooting to establish the root cause for the ESF
actuation.  During the event, control room operators initiated emergency
operating procedures and manually started train "B" emergency core
cooling equipment (ECCS) as it did not start automatically.  The cause
for ECCS train "B" equipment not starting automatically was due to the
loss of power to vital inverter 2-IV which supplies electrical power to
train "B".  All systems responded as designed during the event except for
the following plant equipment operational problems:

The 2A motor driven auxiliary feedwater (MDAFW) pump failed to start.
Subsequently, the 2A MDAFW pump breaker was replaced and the pump was
placed in service satisfactorily.

During the event two steam generator pressure operated relief valves
(SG-PORVs) malfunctioned and operator action was taken to manually close
the SG-PORVs.

The resident inspectors have been following the licensee's
troubleshooting activities and corrective actions.  Two Region II
inspectors are being sent to the site to assist in a special inspection
of the event.

Currently Unit 2 is in Mode 3 hot-standby conditions.

Contact:  PAUL FREDRICKSON           (404)562-4530
_
Page Last Reviewed/Updated Thursday, March 29, 2012