United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for January 19, 1999

                       Headquarters Daily Report

                         JANUARY 19, 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 - HEADQUARTERS JANUARY 19, 1999

MR Number: H-99-0001

                           NRR DAILY REPORT ITEM
                           GENERIC COMMUNICATIONS



Subject: GENERIC LETTER 98-01, SUPPLEMENT 1 ISSUED

NRC Generic Letter No. 98-01, Supplement 1: Year 2000 Readiness of
Computer Systems at Nuclear Power Plants, Dated January 14, 1999

The U. S. Nuclear Regulatory Commission issued this generic letter
supplement to provide addresses with a voluntary alternative response to
that required in Generic Letter 98-01 on Year 2000 (Y2K) readiness of
their respective facilities.

Technical Contact:  Matt Chiramal, NRR
                    301-415-2845
                    E-Mail: mxc@nrc.gov

Lead Project Manager:   Allen G. Hansen, NRR
                        301-415-1390
                        E-Mail: agh@nrc.gov
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REGION III  MORNING REPORT     PAGE  2          JANUARY 19, 1999

Licensee/Facility:                     Notification:

Commonwealth Edison Co.                MR Number: 3-99-0003
Braidwood 1                            Date: 01/19/99
Braceville,Illinois                    Licensee via ENS
Dockets: 50-456
PWR/W-4-LP

Subject: LOSS OF APPROXIMATELY 35 PERCENT OF CONTROL ROOM ANNUNCIATORS

Discussion:

ComEd's Braidwood Station Unit 1 experienced a loss of approximately 35
percent of the control room safety related annunciators when redundant
power supplies failed. Upon recognition, the licensee declared an unusual
event at 8:17 p.m. on 1/18/99, made the appropriate 10 CFR 50.72
notification, and summoned the proper people to the site for trouble
shooting and repair.

One power supply rectifier failed on 1/17/99 and the licensee was
preparing to conduct repairs and the second rectifier failed on 1/18/99.
The second power supply failure was identified when operators were
investigating a turbine supervisory alarm and found that the alarm system
was not behaving as expected. The second failed power supply is the
backup to the first failed power supply. Additional operators were
assigned to Unit 1 to monitor the plant and no indications were lost.
When the failed power supply rectifiers were identified, they were
replaced, the system was tested and returned to service.

At 4:07 a.m. on 1/19/99, the unusual event was terminated.

The licensee is continuing to investigate the cause of the failures.

Regional Action:

The resident inspectors are following the licensees investigation.

Contact:  Michael Jordan             (630)829-9637
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