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During a review of a High-Energy Line Break (HELB) calculation, valve FBV0146 on a 3" Auxiliary Steam line, FB-093-HBD-3", was found to be kept normally open. This is not consistent with HELB analysis, which assumes flow in line FB-093-HBD-3" is restricted by an orifice plate or isolated by FBV0146. This HELB analysis classified FB-093-HBD-3" as a moderate-energy line downstream of FBV0146 as a result of line isolation. No orifice plate was installed, and line FB-093-HBD-3" downstream of the FBV0146 is considered a high-energy line if FBV0146 is open. A room containing line FB-093-HBD-3" downstream from FBV0146 includes several components, the most critical of which are two RCS (Reactor Coolant System) pressure transmitters in one train which are used to provide indications during post-accident conditions. This configuration is therefore outside of current HELB analysis and potentially represents a condition that significantly degrades plant safety. Valve FBV0146 was closed at 1522. The NRC resident inspectors have been notified.

• * * RETRACTION FROM KEITH CRIBLEZ TO VINCE KLCO ON 1/21/2010 AT 1739 * * *

On 12/15/2009, EN #45571 provided notification that valve FBV0146 on Auxiliary Steam line FB-093-HBD-3 was found to be kept normally open. This configuration was not consistent with High Energy Line Break (HELB) analysis which assumes flow beyond this valve to be restricted or isolated. An engineering evaluation was subsequently performed for the rooms containing this line downstream of FBV0146. This evaluation has determined that all safety-related components in the affected rooms would be able to perform their safety functions in the event of a line break. Pipe whip, jet impingement, compartment over pressurization, flooding, and internal missiles resulting from a postulated line break would not prevent any safety-related equipment from performing its design function. As supported by this evaluation, this condition does not meet the criteria for an unanalyzed condition that significantly degrades plant safety as stated in 10CFR 50.72(b)(3)(ii)(B). Therefore, the notification made on 12/15/2009 is hereby retracted. The (NRC) Resident Inspectors have been notified. Notified the R4DO (Werner).