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At 0920 on June 10, 2009, technicians (performing) a Halon detection functional surveillance found a No. 10 AWG Tefzel coated conductor that ran in the Division 1, Division 2, and non-divisional cable trough in the Main Control Room subfloor panels. The conductor is terminated at a ring lug to a bus bar on one end, and the termination point on the other end is unknown. The Tefzel coating is combustible. This is reportable as an 8 hour report in accordance with 10 CFR 50.72(b)(3)(ii)(B) as 'any condition that results in the nuclear power plant being in an unanalyzed condition that significantly degrades plant safety.' Clinton is required to have divisional separation in the event of a fire, and if the cable caught fire both Division 1 and Division 2 could be impacted. The station is working on determining the design function of the conductor and what the conductor is connected to. The licensee will notify the on-site state IEMA Resident Inspector. The licensee will notify the NRC Resident Inspector.

• * * UPDATE AT 1655 EDT ON 6/15/09 FROM REANDEAU TO HUFFMAN * * *

The licensee is retracting this event based on the following: Further inspection of the duct run in the subfloor section reveals that the #10 AWG Tefzel coated conductor is actually 2 separate conductors, not just one. Each is a ground for the flex conduits in the divisional ducts (as described in USAR section 8.3.1.4.5.5), installed to ensure that hot shorts in the wiring inside the flex conduit will melt the upstream fuses. In addition, between the division 1 and division 2 duct sections, there is a metal barrier in the duct, providing the separation barrier between redundant Class 1E equipment (Division 1 and Division 2 cables) as described in IEEE 384. Also, further review shows that Tefzel is flame retardant and non-propagating, passes the IEEE 383 and UL vertical tray flame test, and is rated 'non-burning' under ASTM D635. There is no divisional separation issue and no condition that results in the nuclear power plant being in an unanalyzed condition that significantly degrades plant safety. The licensee has notified the on-site state IEMA Resident Inspector and NRC Resident Inspector. R3DO (Lipa) notified.