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During the performance of the High Pressur … During the performance of the High Pressure Core Spray system (HPCS) quarterly pump and valve operability test, the waterleg pump discharge low pressure alarm was unable to be cleared. It was determined that the waterleg pump discharge check valve had failed to open to provide keepfill flow.</br>The HPCS system had been declared (inoperable at 0818 for a planned surveillance activity. At 1109, the low pressure alarm came in as expected, but was not able to be cleared. Subsequent mechanical agitation of the waterleg pump discharge check valve caused the valve to open and the low pressure condition to clear.</br>Tech Spec 3.5.1 is applicable. Entry time 0818 on 12/17/04. </br>Action is to restore HPCS to Operable within 14 days.</br>NRC Resident Inspector was notified.</br>* * * UPDATE ON 01/05/05 @1211 BY KEN MEADE TO CHAUNCEY GOULD * * * RETRACTION</br>An 8 hour notification was made on December 17, 2004, in accordance with 10CFR50.72(b)(3)(v)(C) and 10CFR50.72(b)(3)(v)(D). The report was made due to a potential loss of the High Pressure Core Spray (HPCS) system safety function as a result of the loss of keep-fill pressure.</br>The water-leg pump discharge check valve was determined to be the most likely cause of the loss of keep-fill pressure and was replaced. A preliminary investigation has determined that the water-leg pump discharge check valve had sufficient corrosion products (on the rising stem) to cause the valve disk to stick. With the check valve not able to fully open, the system low pressure alarm was activated.</br>The lowest system pressure, about 24 psig, was determined to be just below the alarm setpoint of 27 psig. The alarm setpoint includes a 10 psig margin between receipt of the alarm and the pressure at which the piping would start to void. The pressure, 24 psig, was equivalent to the static head provided by the Condensate Storage Tank (CST) to the HPCS system. This alignment is the method used to maintain the system filled when the water-leg pump is unavailable.</br>The 24 psig system pressure was adequate to maintain the system full. Since the system pressure was adequate and the HPCS system was maintained full, the safety function of the system was not adversely affected. Since the safety function was not affected, there is no reportable condition and Event Notification 41269 is retracted.</br>The NRC Resident Inspector was notified..
The NRC Resident Inspector was notified.
16:09:00, 17 December 2004 +
16:40:00, 17 December 2004 +
16:09:00, 17 December 2004 +
During the performance of the High Pressur … During the performance of the High Pressure Core Spray system (HPCS) quarterly pump and valve operability test, the waterleg pump discharge low pressure alarm was unable to be cleared. It was determined that the waterleg pump discharge check valve had failed to open to provide keepfill flow.</br>The HPCS system had been declared (inoperable at 0818 for a planned surveillance activity. At 1109, the low pressure alarm came in as expected, but was not able to be cleared. Subsequent mechanical agitation of the waterleg pump discharge check valve caused the valve to open and the low pressure condition to clear.</br>Tech Spec 3.5.1 is applicable. Entry time 0818 on 12/17/04. </br>Action is to restore HPCS to Operable within 14 days.</br>NRC Resident Inspector was notified.</br>* * * UPDATE ON 01/05/05 @1211 BY KEN MEADE TO CHAUNCEY GOULD * * * RETRACTION</br>An 8 hour notification was made on December 17, 2004, in accordance with 10CFR50.72(b)(3)(v)(C) and 10CFR50.72(b)(3)(v)(D). The report was made due to a potential loss of the High Pressure Core Spray (HPCS) system safety function as a result of the loss of keep-fill pressure.</br>The water-leg pump discharge check valve was determined to be the most likely cause of the loss of keep-fill pressure and was replaced. A preliminary investigation has determined that the water-leg pump discharge check valve had sufficient corrosion products (on the rising stem) to cause the valve disk to stick. With the check valve not able to fully open, the system low pressure alarm was activated.</br>The lowest system pressure, about 24 psig, was determined to be just below the alarm setpoint of 27 psig. The alarm setpoint includes a 10 psig margin between receipt of the alarm and the pressure at which the piping would start to void. The pressure, 24 psig, was equivalent to the static head provided by the Condensate Storage Tank (CST) to the HPCS system. This alignment is the method used to maintain the system filled when the water-leg pump is unavailable.</br>The 24 psig system pressure was adequate to maintain the system full. Since the system pressure was adequate and the HPCS system was maintained full, the safety function of the system was not adversely affected. Since the safety function was not affected, there is no reportable condition and Event Notification 41269 is retracted.</br>The NRC Resident Inspector was notified..
The NRC Resident Inspector was notified.
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99 +
00:00:00, 5 January 2005 +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
02:22:02, 2 March 2018 +
16:40:00, 17 December 2004 +
true +
false +
0.0217 d (0.52 hours, 0.0031 weeks, 7.12296e-4 months) +
16:09:00, 17 December 2004 +
URL"URL" is a <a href="/Special:Types/URL" title="Special:Types/URL">type</a> and predefined property provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a> to represent URI/URL values.