Morning Report for April 27, 1999

                       Headquarters Daily Report

                         APRIL 27, 1999

                    REPORT             NEGATIVE            NO INPUT
                    ATTACHED           INPUT RECEIVED      RECEIVED

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

MR Number: H-99-0037

                           NRR DAILY REPORT ITEM
                           GENERIC COMMUNICATIONS

Subject: Information Notice 99-12 is being issued April 28, 1999

dated April 28, 1999

The NRC is issuing this information notice (IN) to inform addressees of
observations made by NRC staff during audits conducted on the Year 2000
(Y2K) readiness programs of twelve plants.

Technical contacts: A. Bryant, NRR              W. Burton, NRR
                    301-415-2712                301-415-2853
                    E-mail:        E-mail:

REGION III  MORNING REPORT     PAGE  2          APRIL 27, 1999

Licensee/Facility:                     Notification:

Commonwealth Edison Co.                MR Number: 3-99-0034
Byron 1                                Date: 04/25/99
Byron,Illinois                         SRI/RI Telecon
Dockets: 50-454

Subject: Byron Unit 1 Startup Following Refuel Outage B1R09


The Byron Unit 1 reactor was made critical at 3:56 a.m. on 4/24/99 and
the main generator was synchronized to the grid at 5:05 a.m. on 4/25/99
which ended the B1R09 refueling outage. The outage was planned for a
duration of 26 days and lasted 29 days. The major activities completed
were refueling; main generator rotor removal, inspection and repair; main
turbine maintenance; 1A reactor coolant loop cold leg stop valve
inspection and repair; reactor coolant pumps 1C and 1D seal replacement;
and emergency diesel generator inspections. NRC resident and regional
inspectors, and an Illinois Department of Nuclear Safety Inspector
monitored the activities.

Regional Action:

The resident inspectors monitored the startup activities.

Contact:  Michael Jordan             (630)829-9637
REGION III  MORNING REPORT     PAGE  3          APRIL 27, 1999

Licensee/Facility:                     Notification:

Commonwealth Edison Co.                MR Number: 3-99-0035
Braidwood 2                            Date: 04/25/99
Braceville,Illinois                    Resident Inspector via Telecon
Dockets: 50-457

Subject: Reactor Shutdown for Refueling Outage A2R07


The Braidwood Unit 2 reactor refueling outage A2R07 was started on
4/24/99. The main generator output breakers were opened at 12:02 a.m. and
the reactor was manually tripped at 12:20 a.m. The outage duration is
planned for 26 days and the main activities include refueling, main
turbine maintenance, main generator inspections, 1A and 1B emergency
diesel generator inspections, motor operated valve work, and completion
of the 211 and 212 battery modifications. NRC resident and regional
inspectors will monitor the ongoing activities.

Regional Action:

This is for information only.

Contact:  Michael Jordan             (630)829-9637
REGION IV  MORNING REPORT     PAGE  4          APRIL 27, 1999

Licensee/Facility:                     Notification:

Entergy Operations, Inc.               MR Number: 4-99-0015
Arkansas Nuclear 1 2                   Date: 04/27/99
Russelville,Arkansas                   SRI via telecon
Dockets: 50-313,50-368



On April 23, 1999, Arkansas Nuclear One (ANO) installed upgraded software
and a new operating system as part of their program to make the SBO
diesel generator Y2K compliant. The SBO diesel generator has an advanced
touch screen control/display system with control/display locations in
both the control room and locally at the machine. The software and
operating system upgrade was planned to be completed just prior to the
regularly scheduled surveillance test, which was revised to allow
verification of the functionality of the newly installed software. The
test was initially performed with the computer date at the present date
and then reperformed with the date advancing from the year 1999 to 2000.
During the performance of both tests (i.e., with the computer at the
present date and at the advanced date), the diesel would only carry a
load of approximately 500 Kw, instead of its expected load of 4400 Kw.

After verifying that the diesel would not properly load, the licensee
removed the new software and operating system and reinstalled the old
version. The test was reperformed and the diesel loaded as expected. To
ensure that the diesel would remain operable for Y2K, the computer date
was reset to 1987.

The licensee has compared the old and new versions of the software in an
attempt to identify the cause of the anomaly. No differences have been
identified to date, and as a result, the root cause of this problem has
not yet been identified. The licensee will continue their troubleshooting
efforts in an attempt to identify the problem.

The licensee has stated that no similar problems with newly installed
software have been encountered. Furthermore, they believe that this
anomaly is not a Y2K problem since the failure to properly load did not
specifically occur when the date on the computer rolled over from 1999 to

This information has been coordinated with the Office of Public Affairs.

Regional Action:

For information only.

Contact:  Phil Harrell               (817)860-8250

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