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On 10/10/2007 a 2245, the Unit 2 High Pres … On 10/10/2007 a 2245, the Unit 2 High Pressure Coolant Injection (HPCI) Pump developed a leak of approximately 5 gpm due to a suspected pump seal failure. </br>HPCI was in service for a scheduled surveillance test per plant procedure OPT-09.2, HPCI System Operability Test.</br>When the leak was identified, operators secured HPCI. The leak was isolated by securing the pump, closing the pump suction isolation valves, isolating the keep fill supply valves. Operators declared the Unit 2 HPCI System inoperable when the keep fill system was isolated.</br>No automatic system isolation or actuation set points were reached.</br>Safety significance is minimal due to the operability and availability of redundant systems. If a Loss of Coolant Accident (LOCA) were to occur the Reactor Core Isolation Cooling (RCIC) System would automatically inject and if necessary the Automatic Depressurization System (ADS) would depressurize the reactor pressure vessel allowing low pressure Emergency Core Cooling Systems (ECCS) to inject. All low pressure ECCS are operable.</br>Plant risk has been evaluated and remains 'Green'.</br>The Unit 2 HPCI system has been removed from service. The pump suction isolation valves have been closed. Injection piping keep fill connections have been isolated. These actions were taken to stop the leakage of system water out of the failed pump seal.</br>Actions have been taken to protect redundant safety systems, including the RCIC System and ADS.</br>In accordance with Technical Specification 3.5.1 Required Actions: RCIC has been verified to be operable, and HPCI must be restored to operable status within 14 days.</br>HPCI pump seal replacement is being planned in accordance with the site's Work Management process. This event has been entered into the sites Corrective Action Program and an investigation into the cause of the seal failure will be performed.</br>The licensee notified the NRC Resident Inspector.</br>* * * RETRACTION RECEIVED FROM LEE GRZEK TO JOE O'HARA AT 1045 EST ON 1/30/08 * * *</br>On October 11, 2007, at 0520 hours, the control room Supervisor made a notification (Event Number 43711) to the NRC Operations Center in accordance with. 10 CFR 50.72(b)(3)(v)(D) (i.e., any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident). The notification was made as a result of the High Pressure Coolant Injection (HPCI) system being declared inoperable due to indications of a main pump seal leak. Specifically, water was discovered leaking an approximate five gallons per minute from the main pump turbine side seal during performance of OPT-09.2, 'HPCI System Operability Test.'</br>Basis for Retraction</br>Unit 2 HPCI was declared inoperable when the main pump seal leak was first identified. Upon further detailed engineering evaluation, it has been determined that the HPCI system was not rendered inoperable as a result of the condition identified on October 10, 2007, and was able to fulfill its safety functions in the degraded condition.</br>The HPCI pump uses seal purge water piping in combination with mechanical seals to limit shaft leakage. The investigation found debris blocking the seal purge piping, which led to the seal faces overheating and subsequent failure. Water intrusion into the oil system was determined to be the limiting impact of the seal failure. The limiting event for HPCI was determined to be 4.1 hours of operation during a loss of Feedwater event with HPCI only, due to the short runtimes followed by long idle times which maximize water intrusion. The evaluation concluded that the HPCI pump would be able to operate for 4.1 hours, as required for the limiting event, and would be available for 8 hours. Thus, Unit 2 HPCI was degraded but able to meet all required safety functions.</br>On this basis, the HPCI system was capable of performing its safety functions to mitigate the consequences of an accident and the issue is not reportable under 10 CFR 50.72(b)(3)(v)(D).</br>The NRC Resident was notified of this retraction.</br>Notified R2DO(Bonner) of this retraction.
Notified R2DO(Bonner)
02:45:00, 11 October 2007 +
43,711 +
05:20:00, 11 October 2007 +
02:45:00, 11 October 2007 +
On 10/10/2007 a 2245, the Unit 2 High Pres … On 10/10/2007 a 2245, the Unit 2 High Pressure Coolant Injection (HPCI) Pump developed a leak of approximately 5 gpm due to a suspected pump seal failure. </br>HPCI was in service for a scheduled surveillance test per plant procedure OPT-09.2, HPCI System Operability Test.</br>When the leak was identified, operators secured HPCI. The leak was isolated by securing the pump, closing the pump suction isolation valves, isolating the keep fill supply valves. Operators declared the Unit 2 HPCI System inoperable when the keep fill system was isolated.</br>No automatic system isolation or actuation set points were reached.</br>Safety significance is minimal due to the operability and availability of redundant systems. If a Loss of Coolant Accident (LOCA) were to occur the Reactor Core Isolation Cooling (RCIC) System would automatically inject and if necessary the Automatic Depressurization System (ADS) would depressurize the reactor pressure vessel allowing low pressure Emergency Core Cooling Systems (ECCS) to inject. All low pressure ECCS are operable.</br>Plant risk has been evaluated and remains 'Green'.</br>The Unit 2 HPCI system has been removed from service. The pump suction isolation valves have been closed. Injection piping keep fill connections have been isolated. These actions were taken to stop the leakage of system water out of the failed pump seal.</br>Actions have been taken to protect redundant safety systems, including the RCIC System and ADS.</br>In accordance with Technical Specification 3.5.1 Required Actions: RCIC has been verified to be operable, and HPCI must be restored to operable status within 14 days.</br>HPCI pump seal replacement is being planned in accordance with the site's Work Management process. This event has been entered into the sites Corrective Action Program and an investigation into the cause of the seal failure will be performed.</br>The licensee notified the NRC Resident Inspector.</br>* * * RETRACTION RECEIVED FROM LEE GRZEK TO JOE O'HARA AT 1045 EST ON 1/30/08 * * *</br>On October 11, 2007, at 0520 hours, the control room Supervisor made a notification (Event Number 43711) to the NRC Operations Center in accordance with. 10 CFR 50.72(b)(3)(v)(D) (i.e., any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident). The notification was made as a result of the High Pressure Coolant Injection (HPCI) system being declared inoperable due to indications of a main pump seal leak. Specifically, water was discovered leaking an approximate five gallons per minute from the main pump turbine side seal during performance of OPT-09.2, 'HPCI System Operability Test.'</br>Basis for Retraction</br>Unit 2 HPCI was declared inoperable when the main pump seal leak was first identified. Upon further detailed engineering evaluation, it has been determined that the HPCI system was not rendered inoperable as a result of the condition identified on October 10, 2007, and was able to fulfill its safety functions in the degraded condition.</br>The HPCI pump uses seal purge water piping in combination with mechanical seals to limit shaft leakage. The investigation found debris blocking the seal purge piping, which led to the seal faces overheating and subsequent failure. Water intrusion into the oil system was determined to be the limiting impact of the seal failure. The limiting event for HPCI was determined to be 4.1 hours of operation during a loss of Feedwater event with HPCI only, due to the short runtimes followed by long idle times which maximize water intrusion. The evaluation concluded that the HPCI pump would be able to operate for 4.1 hours, as required for the limiting event, and would be available for 8 hours. Thus, Unit 2 HPCI was degraded but able to meet all required safety functions.</br>On this basis, the HPCI system was capable of performing its safety functions to mitigate the consequences of an accident and the issue is not reportable under 10 CFR 50.72(b)(3)(v)(D).</br>The NRC Resident was notified of this retraction.</br>Notified R2DO(Bonner) of this retraction.
Notified R2DO(Bonner)
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