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On 11/9/03 at 2315 (EST), with Unit 2 in M … On 11/9/03 at 2315 (EST), with Unit 2 in Mode 3 in preparation for a Refueling Outage, an unanticipated ESF actuation occurred. With one Main Feedwater Pump (MFP) reset and one MFP tripped per the General Operating Procedures, Main Condenser Vacuum was being broken. Low Condenser vacuum caused the trip of the reset MFP. The signal for trip of two MFPs caused an Aux Feedwater (AFW) start. AFW was in service in manual control per procedure when the start signal was received; however, the start signal caused the Level Control Valves (LCVs) to reposition to their accident position.</br>The licensee notified the NRC Resident Inspector.</br>* * * RETRACTION PROVIDED BY B HARRIS TO JEFF ROTTON AT 1442 EST ON 01/05/04 * * *</br>On November 9, 2003, after the planned Unit 2 reactor shutdown for refueling outage number 12, an auxiliary feedwater system start signal was initiated. During the shutdown, the auxiliary feedwater pumps (AFW) were started and both main feedwater pumps (MFP) had been tripped. Following transition from emergency operating procedure to the normal plant shutdown procedure, the feedwater isolation signal and one MFP trip were reset to allow shutdown of the turbine-driven pump, in accordance with plant procedures. As a result of the reactor coolant temperature decreasing below 540 degrees Fahrenheit, emergency boration was performed, and subsequently, control room personnel closed the main steam isolation valves (MSIVs) to limit cooldown of the RCS. After closure of the MSIVs, Operations personnel broke main condenser vacuum in accordance with plant procedures. The operators knew by their procedure that this would result in a low-condenser vacuum trip signal to the reset MFP trip bus and, with both MFPs trip bus tripped, the logic would be completed for initiation of an AFW start signal. The procedure states 'Breaking main condenser vacuum will cause loss of main feed pump turbine condenser vacuum to both MFPs resulting in an ESF actuation.'</br>On November 10, 2003, at 0039 Eastern standard time, NRC was notified in accordance with 10 CFR 50.72 (b)(3)(iv)(A) of the ESF actuation (event notification No. 40305).</br>10 CFR 50.72 and 50.73 requires reporting of any event or condition that results in valid actuation of any of the systems listed in paragraph (b)(3)(iv)(B) except when the actuation results from and is part of a pre-planned sequence during testing or reactor operation. NUREG 1022 states that the intent is to require reporting of actuations of systems that mitigate the consequences of significant events. The breaking of the condenser vacuum was driven by plant conditions. However, the start signal to the AFW system was not to mitigate an event for the condition the plant was in (i.e., both MFPs had been secured and decay heat was being controlled by AFW in accordance with normal operating procedures) and is therefore considered a preplanned event.</br>Based on the above information, the initiation of the AFW start signal is not reportable and the notification is being withdrawn.</br>The licensee has notified the NRC Resident Inspector. Notified R2DO(Ayres) Resident Inspector. Notified R2DO(Ayres)
04:15:00, 10 November 2003 +
00:39:00, 10 November 2003 +
04:15:00, 10 November 2003 +
On 11/9/03 at 2315 (EST), with Unit 2 in M … On 11/9/03 at 2315 (EST), with Unit 2 in Mode 3 in preparation for a Refueling Outage, an unanticipated ESF actuation occurred. With one Main Feedwater Pump (MFP) reset and one MFP tripped per the General Operating Procedures, Main Condenser Vacuum was being broken. Low Condenser vacuum caused the trip of the reset MFP. The signal for trip of two MFPs caused an Aux Feedwater (AFW) start. AFW was in service in manual control per procedure when the start signal was received; however, the start signal caused the Level Control Valves (LCVs) to reposition to their accident position.</br>The licensee notified the NRC Resident Inspector.</br>* * * RETRACTION PROVIDED BY B HARRIS TO JEFF ROTTON AT 1442 EST ON 01/05/04 * * *</br>On November 9, 2003, after the planned Unit 2 reactor shutdown for refueling outage number 12, an auxiliary feedwater system start signal was initiated. During the shutdown, the auxiliary feedwater pumps (AFW) were started and both main feedwater pumps (MFP) had been tripped. Following transition from emergency operating procedure to the normal plant shutdown procedure, the feedwater isolation signal and one MFP trip were reset to allow shutdown of the turbine-driven pump, in accordance with plant procedures. As a result of the reactor coolant temperature decreasing below 540 degrees Fahrenheit, emergency boration was performed, and subsequently, control room personnel closed the main steam isolation valves (MSIVs) to limit cooldown of the RCS. After closure of the MSIVs, Operations personnel broke main condenser vacuum in accordance with plant procedures. The operators knew by their procedure that this would result in a low-condenser vacuum trip signal to the reset MFP trip bus and, with both MFPs trip bus tripped, the logic would be completed for initiation of an AFW start signal. The procedure states 'Breaking main condenser vacuum will cause loss of main feed pump turbine condenser vacuum to both MFPs resulting in an ESF actuation.'</br>On November 10, 2003, at 0039 Eastern standard time, NRC was notified in accordance with 10 CFR 50.72 (b)(3)(iv)(A) of the ESF actuation (event notification No. 40305).</br>10 CFR 50.72 and 50.73 requires reporting of any event or condition that results in valid actuation of any of the systems listed in paragraph (b)(3)(iv)(B) except when the actuation results from and is part of a pre-planned sequence during testing or reactor operation. NUREG 1022 states that the intent is to require reporting of actuations of systems that mitigate the consequences of significant events. The breaking of the condenser vacuum was driven by plant conditions. However, the start signal to the AFW system was not to mitigate an event for the condition the plant was in (i.e., both MFPs had been secured and decay heat was being controlled by AFW in accordance with normal operating procedures) and is therefore considered a preplanned event.</br>Based on the above information, the initiation of the AFW start signal is not reportable and the notification is being withdrawn.</br>The licensee has notified the NRC Resident Inspector. Notified R2DO(Ayres) Resident Inspector. Notified R2DO(Ayres)
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