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During performance of the quarterly HPCI valve stroke test the HV-55-2F006, HPCI pump discharge isolation valve to Core Spray failed to open within the maximum allowed time. The HV-55-2F006 valve is a motor operated valve and the maximum allowed opening time is 17.25 seconds. The valve was given an open signal via the hand switch as required by the test but did not initially respond. Several minutes later the valve went full open. HPCI was declared inoperable at 0315 on 6/21/2007. Cause for valve stroke time failure is not known at this time. As a result, the licensee is in a 14 day shutdown LCO. The licensee notified the NRC Resident Inspector.

• * * RETRACTION FROM ARNOSKY TO HUFFMAN AT 0807 EDT ON 8/01/07 * * *

This is a retraction of the event notification made on 6/21/07 at 04:05 hours EDT. This event (#43436) was initially reported as a condition that at the time of discovery could have prevented the fulfillment of the High Pressure Coolant Injection (HPCI) system safety function under the requirement of 10CFR50.72(b)(3)(v)(D). The Unit 2 HPCI system was declared inoperable due to failure of the HPCI pump discharge isolation valve to Core Spray to open within the maximum allowed time during surveillance testing. The valve was required to open within 17.25 seconds but opened several minutes after the open signal was initiated. The open contactor was replaced and the valve was successfully tested. The affected valve was declared operable on 6/22/07 at 04:07 hours. The HPCI system was restored to operable on 6/23/07 at 04:07 hours following completion of maintenance and testing activities. An evaluation determined that HPCI was capable of injecting sufficient flow to complete its safety function through the unaffected operable injection flow path to the feedwater header. The achievable flow rate would have exceeded the leakage from a one-inch liquid line break. Also, HPCI operation remained capable of being terminated by operator action during an ATWS event. Therefore, HPCI remained capable of fulfilling its safety function while the injection flow path to Core Spray was unavailable. A condition did not exist at the time of discovery that could have prevented the fulfillment of the HPCI safety function. The licensee notified the NRC Resident Inspector. R1DO (White) notified.

A division 2 Primary Containment Isolation Instrument System component inoperable required the manual isolation of High Pressure Coolant Injection (HPCI) outboard Primary Containment Isolation valves (PCIV). This isolation was required by T/S action 3.3.2.b.1. This report made pursuant to 10CFR 50,72 (b)(3)(v)(D) for the inability of single train system to mitigate the consequences of an accident. At approximately midnight on 10/7/06, Control Room Operators received a Div 2 Steam Leak Detection Trouble Alarm. Troubleshooting identified the failure as associated with the GE NUMAC drawer where temperature inputs are processed. The applicable 14-day T/S LCO Action Statement requires completion of repairs within 6 hours or isolation of HPCI 1 hour later. HPCI was isolated at 0657 EDT. There was no I&C work in progress at the time of the failure. Repair parts are available and onsite. The licensee informed the NRC Resident Inspector.

• * * RETRACTION RECEIVED FROM EDWARD DENNIN TO JOE O'HARA AT 1500 ON 12/04/06 * * *

This is a retraction of the event notification made on 10/07/06 at 11:05 hours. This event (#42883) was initially reported as a safety system functional failure under the requirement of 10CFR50.72(b)(3)(v)(D). Unit 2 High Pressure Coolant Injection (HPCI) system was declared inoperable due to a manual closure of the HPCI steam line outboard primary containment isolation valve (PCIV). The PCIV was closed to support the maintenance on an inoperable steam leak detection (SLD) channel and to satisfy the Technical Specification (TS) 3.3.2 Isolation Actuation Instrumentation action statement. The event was initiated at 00:06 hours by a trouble alarm due to a 'self test fault' condition on the Division 2 SLD instrument channel. Troubleshooting determined that the instrument channel was inoperable. TS 3.3.2 Action 'b.1' requires the channel to be restored to operable status within 6 hours. Since this action could not be completed Table 3.3.2-1 Action 23 was applicable. Action 23 required the affected system isolation valves to be closed within one hour and the system (HPCI) to be declared inoperable. This action was completed at 06:57 hours. Two modules were replaced in the SLD instrument chassis. The instrument channel was tested satisfactorily and returned to service, Unit 2 HPCI was restored to operable status at 23:48 hours. The system was removed from service as part of a planned evolution to conduct maintenance in accordance with an approved procedure and the plant's Technical Specifications. The system was secured for the purpose of conducting maintenance on an inoperable SLD instrument channel and completing the TS action. The failed instrument did not adversely affect the HPCI system's capability of performing its safety function. HPCI remained capable of automatic initiation until the PCIV was manually closed to support maintenance by completing the TS actions. A condition did not exist at the time of discovery that could have prevented the fulfillment of the HPCI safety function. The licensee notified the NRC Resident Inspector. Notified R1DO(Sykes).

On 3/19/04 at 14:08 PM EST, the Unit-1. HPCI system was declared inoperable due to a hand-switch failure, which prevented main control room operation of the HV-055-1F0O1 HPCI steam admission valve. The system had just successfully completed its functional surveillance test and the switch broke resulting in the operators using an, alternate means to shutdown the HPCI system. The steam admission valve is not a PCIV. The valve was open all the time; the system was shutdown using an alternate procedure. The system is now blocked for hand-switch replacement. This report is being made pursuant to 10CFR50.72(b)(3)(v) for failure of a single train accident mitigation system. The NRC Resident inspector was notified. Operators entered the unit into a 14 day LCO for declaring HPCI system inoperable.

• • • • • RETRACTED ON 4/14/04 AT 12:56 FROM GAMBLE TO LAURA*****

This is a retraction of the event notification made on 3/19/04 at 21:00 hours. This event (#40600) was initially reported as a safety system functional failure under the requirement of 10CFR50.72(b)(3)(v)(D). Unit 1 High Pressure Coolant Injection (HPCI) system was declared inoperable due to a handswitch failure that prevented operation of the HV-055-1F001 HPCI steam admission valve from the main control room. The handswitch failed while attempting to close the steam admission valve during system shutdown at the conclusion of surveillance testing. The operator then closed the outboard steam line isolation valve to complete the system shutdown. HPCI is automatically initiated by low reactor level or high drywell pressure signals. Manual HPCI initiation for inventory makeup is performed by depressing the initiation pushbutton. Both automatic initiation and manual initiation using the pushbutton open the steam admission valve. The failed handswitch did not adversely affect the initiation of the HPCI system in the inventory makeup mode. The manual startup of the system in the test mode of operation is unavailable when the handswitch is failed. The test mode can be used to remove decay heat following an isolation of the main steam lines but it is not a credited safety function. The steam admission valve handswitch would not be used to shutdown the system when an automatic initiation signal is present; the outboard steam line isolation valve would be closed to secure the system. This is the method that was used to secure the system during the surveillance test. The handswitch is mainly used to startup and secure the system during surveillance testing. The system was removed from service as part of a planned evolution to conduct surveillance testing in accordance with an approved procedure and the plant's Technical Specifications. The system was secured for the purpose of concluding the surveillance test and replacing the handswitch. The failed handswitch did not adversely affect the systems capability of performing its safety function. A condition did not exist at the time of discovery that could have prevented the fulfillment of the HPCI safety function. Notified R1DO (B. MCDERMOTT).