Morning Report for January 19, 1999
Headquarters Daily Report JANUARY 19, 1999 *************************************************************************** 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 _ 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 _
Page Last Reviewed/Updated Wednesday, March 24, 2021
Page Last Reviewed/Updated Wednesday, March 24, 2021