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At 1140 (CDT) on August 24th, Unit 2 recei … At 1140 (CDT) on August 24th, Unit 2 received Essential Service Water (SX) discharge header pressure low and SX strainer delta pressure high alarms indicative of high flow. At the time, a 2B SX ASME surveillance was in progress which involved field operations by Equipment Operators (EO's). At the time of the event, SX discharge header pressure dropped to 65 psig, less than the 89 psig necessary for operability. The Control Room responded by directing the EO's to restore SX discharge header pressure, which was promptly restored.</br>The 2B SX ASME surveillance sets initial conditions prior to data collection. The surveillance has the total SX flow be adjusted to 24000 gpm via the U2 Component Cooling Water (CC) heat exchanger outlet throttle valve, 2SX007. The subject flow was intended to be measured via an installed ultrasonic flow gauge 2FE-SX147. The EO's, instead used the U2 CC heat exchanger flow gauge 2FE-SX031. As a result, in an attempt to achieve 24000 gpm through the U2 CC heat exchanger, total SX flow exceeded the 24000 gpm since the U2 CC heat exchanger is but one of many loads the 2B SX pump is serving.</br>For the 5 minutes described above, the SX system was in a lineup that may have prevented it to fulfill its safety function and placed Unit 2 in a potentially unanalyzed condition. This condition is still being evaluated.</br>Site Engineering has determined no runout conditions existed. The licensee notified the NRC Resident Inspector.</br>* * * RETRACTION FROM JOE KLEVORN TO VINCE KLCO ON 10/19/2011 AT 1626 EDT* * *</br>The evaluation of the condition has been completed. Based on Essential Service Water (SX) system flow model runs performed, the conditions that existed at the time of the low SX header pressure would have resulted in low flow supplied to multiple safety related components. However, the safety function to provide necessary cooling to required safety-related safe shutdown equipment would have been met under design basis conditions with the auto-start of the 2A SX pump. Therefore, this did not result in a condition that could have prevented fulfillment of a safety function or in an unanalyzed condition that significantly degraded plant safety. Therefore, ENS notification 46203 is being retracted.</br>The licensee notified the NRC Resident Inspector.</br>Notified the R3DO (Daley).dent Inspector.
Notified the R3DO (Daley).
16:40:00, 24 August 2010 +
46,203 +
20:02:00, 24 August 2010 +
16:40:00, 24 August 2010 +
At 1140 (CDT) on August 24th, Unit 2 recei … At 1140 (CDT) on August 24th, Unit 2 received Essential Service Water (SX) discharge header pressure low and SX strainer delta pressure high alarms indicative of high flow. At the time, a 2B SX ASME surveillance was in progress which involved field operations by Equipment Operators (EO's). At the time of the event, SX discharge header pressure dropped to 65 psig, less than the 89 psig necessary for operability. The Control Room responded by directing the EO's to restore SX discharge header pressure, which was promptly restored.</br>The 2B SX ASME surveillance sets initial conditions prior to data collection. The surveillance has the total SX flow be adjusted to 24000 gpm via the U2 Component Cooling Water (CC) heat exchanger outlet throttle valve, 2SX007. The subject flow was intended to be measured via an installed ultrasonic flow gauge 2FE-SX147. The EO's, instead used the U2 CC heat exchanger flow gauge 2FE-SX031. As a result, in an attempt to achieve 24000 gpm through the U2 CC heat exchanger, total SX flow exceeded the 24000 gpm since the U2 CC heat exchanger is but one of many loads the 2B SX pump is serving.</br>For the 5 minutes described above, the SX system was in a lineup that may have prevented it to fulfill its safety function and placed Unit 2 in a potentially unanalyzed condition. This condition is still being evaluated.</br>Site Engineering has determined no runout conditions existed. The licensee notified the NRC Resident Inspector.</br>* * * RETRACTION FROM JOE KLEVORN TO VINCE KLCO ON 10/19/2011 AT 1626 EDT* * *</br>The evaluation of the condition has been completed. Based on Essential Service Water (SX) system flow model runs performed, the conditions that existed at the time of the low SX header pressure would have resulted in low flow supplied to multiple safety related components. However, the safety function to provide necessary cooling to required safety-related safe shutdown equipment would have been met under design basis conditions with the auto-start of the 2A SX pump. Therefore, this did not result in a condition that could have prevented fulfillment of a safety function or in an unanalyzed condition that significantly degraded plant safety. Therefore, ENS notification 46203 is being retracted.</br>The licensee notified the NRC Resident Inspector.</br>Notified the R3DO (Daley).dent Inspector.
Notified the R3DO (Daley).
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100 +
00:00:00, 19 October 2011 +
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>.
02:05:43, 2 March 2018 +
20:02:00, 24 August 2010 +
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0.14 d (3.37 hours, 0.0201 weeks, 0.00462 months) +
16:40:00, 24 August 2010 +
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.