United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for October 22, 2004

Headquarters Daily Report

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REGION II

OCONEE KEOWEE HYDRO UNITS

Licensee/Facility:

DUKE ENERGY CORP.
Oconee 1, Oconee 2, Oconee 3
SENECA, South Carolina
Dockets: 05000269, 05000270, 05000287
[1] B&W-L-LP, [2] B&W-L-LP, [3] B&W-L-LP
License No:
Notification:

MR Number: 2-2004-0015
Date: 10/22/2004

Call from Licensee

Discussion:

This Morning Report updates the 10 CFR 50.72 notification dated October 20, 2004, regarding the reported inoperability of both on-site emergency power sources. On October 19, 2004, at 3:57 a.m. (EST), Keowee Unit 1 was removed from service to perform scheduled maintenance. At 5:05 p.m., on October 20, breaker ACB-8, which supplies power to auxiliary loads for Keowee Unit 2 was opened to allow testing of another breaker as part of the post-maintenance testing. ACB-8 failed to re-close due to blown fuses in the closing coil. As a result, at 5:30 p.m., Keowee Unit 2 was declared inoperable. Operators attempted to start Keowee Unit 1, but were unable to start the unit due to a generator voltage regulator problem. At 6:11 p.m., both standby buses were energized from a Lee Combustion Turbine. At
6:28 p.m., ACB-6 was closed to supply power to auxiliary loads for Keowee Unit 2, and at 7:04 p.m., Keowee Unit 2 was declared operable.

The licensee's 10 CFR 50.72 notification reported that between 5:30 p.m. and 6:11 p.m., both on-site emergency power sources were inoperable. The staff has determined that even with ACB-8 out of service, Keowee Unit 2 would have started on an emergency start signal because of its black start capability. Therefore, the safety function of supplying electrical power to the standby buses was not lost.

Regional Action: The resident inspectors are monitoring the licensee's investigation of the event.

Accession Numbers:

Accession No Accession Date
ML042960199 10/22/2004

Contacts:

Name Office Abbrev Phone No E-Mail
ERNSTES, MICHAEL E R2 (404) 562-4638 MEE@nrc.gov
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