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On Sept. 17, 2004, with Watts Bar Unit 1 at 100% power, the main control room was notified that the 99 sirens which make up the Public Prompt Notification System were not functional. The system uses two repeaters to control the sirens. As the remnants of Hurricane Ivan were passing through the Tennessee River Valley one of the repeaters (Pone Knob) was found to be without power around midnight. The siren system operators confirmed the second repeater (Grandview) was still functioning. Approximately 5:00 a.m., however, communications were lost with the second repeater. A maintenance crew was dispatched to the second repeater on loss of communications and they determined the radio transmitter was not functioning at 0955 and Watts Bar was immediately notified. This event is reportable under 10 CFR 50.72(b)(3)(xiii) as a loss of emergency preparedness capability. . As a result of the above siren loss, TVA notified the Tennessee Emergency Management Agency (TEMA) at 10:13a.m. Sept. 17, 2004. This government agency notification is reportable under 10 CFR 50.72(b)(2)(xi). No TVA press release is planned and TVA is not aware of any specific actions planned to be taken by TEMA. Maintenance activities to restore power to the first repeater station by the use of a portable generator are underway. The 99 sirens constitute 100% of the emergency siren capability. The licensee had no estimate for completion of repairs and restoration of the siren capability. The licensee informed the State of Tennessee and the NRC Resident Inspector.

• * * * UPDATE FROM S. SMITH TO M. RIPLEY 1350 ET 09/17/04 * * * *

Restoration of power by use of a portable generator has been completed, reducing the number of non-functional sirens to seven of ninety-nine. The licensee informed local and State authorities, and the NRC Resident Inspector. Notified R2 DO (A. Boland).