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At 2006 (MST), on 3/31/2019, the Palo Verd … At 2006 (MST), on 3/31/2019, the Palo Verde Nuclear Generating Station Unit 1 Shift Manager was informed that leakage was measured from the Train A Emergency Core Cooling System (ECCS) piping at approximately 100 ml/minute through a High Pressure Safety Injection (HPSI) A drain valve. This value exceeds the assumed 3000 ml/hour ECCS leakage for a large break loss of coolant accident analysis. At 0230 (MST) on April 1, 2019, the valve was flushed and the leakage reduced to 10 ml/minute (600 ml/hour) and was no longer above the limit of the safety analysis. This condition is being reported as an unanalyzed condition per 10 CFR 50.72(b)3)(ii)(B) and a condition that could have prevented the fulfillment of a safety function to the control the release of radioactive material per 10 CFR </br>50.72(b)(3)(v)(C). This event did not result in an abnormal release of radioactive material.</br>Notification received by Caty Nolan and emailed to HOO.HOC@NRC.GOV</br>The NRC asked a followup question: </br>Why was the criterion for Control of Radioactive Material selected? </br>per the PVNGS Unit 1 Shift Manager, this criterion was selected due to the potential of exceeding offsite dose projections, post recirculation, following a Design Basis Accident.</br>The resident inspector has been notified.</br>* * * UPDATE ON 05/15/19 AT 1417 EDT FROM SEAN DORNSEIF TO BETHANY CECERE * * *</br>An engineering evaluation concluded that the as-found ECCS leakage would not have degraded the performance of the Pump Room Exhaust Air Cleanup system; therefore, it remained operable. </br>The evaluation also concluded that the as-found leakage was within the analysis margins for HPSI pump hydraulic performance and containment flood level following a Large Break Loss of Coolant Accident; therefore, the ECCS also remained operable. </br>Based on the above information, the condition identified on March 31, 2019, was an unanalyzed condition per 10 CFR 50.72(b)(3)(ii)(B), but did not prevent the fulfillment of the safety function of the structures or systems that are needed to control the release of radioactive material per 10 CFR 50.72(b)(3)(v)(C). </br>The NRC resident inspectors have been informed.</br>Notified R4DO (Proulx).ave been informed.
Notified R4DO (Proulx).
03:06:00, 1 April 2019 +
53,968 +
06:40:00, 1 April 2019 +
03:06:00, 1 April 2019 +
At 2006 (MST), on 3/31/2019, the Palo Verd … At 2006 (MST), on 3/31/2019, the Palo Verde Nuclear Generating Station Unit 1 Shift Manager was informed that leakage was measured from the Train A Emergency Core Cooling System (ECCS) piping at approximately 100 ml/minute through a High Pressure Safety Injection (HPSI) A drain valve. This value exceeds the assumed 3000 ml/hour ECCS leakage for a large break loss of coolant accident analysis. At 0230 (MST) on April 1, 2019, the valve was flushed and the leakage reduced to 10 ml/minute (600 ml/hour) and was no longer above the limit of the safety analysis. This condition is being reported as an unanalyzed condition per 10 CFR 50.72(b)3)(ii)(B) and a condition that could have prevented the fulfillment of a safety function to the control the release of radioactive material per 10 CFR </br>50.72(b)(3)(v)(C). This event did not result in an abnormal release of radioactive material.</br>Notification received by Caty Nolan and emailed to HOO.HOC@NRC.GOV</br>The NRC asked a followup question: </br>Why was the criterion for Control of Radioactive Material selected? </br>per the PVNGS Unit 1 Shift Manager, this criterion was selected due to the potential of exceeding offsite dose projections, post recirculation, following a Design Basis Accident.</br>The resident inspector has been notified.</br>* * * UPDATE ON 05/15/19 AT 1417 EDT FROM SEAN DORNSEIF TO BETHANY CECERE * * *</br>An engineering evaluation concluded that the as-found ECCS leakage would not have degraded the performance of the Pump Room Exhaust Air Cleanup system; therefore, it remained operable. </br>The evaluation also concluded that the as-found leakage was within the analysis margins for HPSI pump hydraulic performance and containment flood level following a Large Break Loss of Coolant Accident; therefore, the ECCS also remained operable. </br>Based on the above information, the condition identified on March 31, 2019, was an unanalyzed condition per 10 CFR 50.72(b)(3)(ii)(B), but did not prevent the fulfillment of the safety function of the structures or systems that are needed to control the release of radioactive material per 10 CFR 50.72(b)(3)(v)(C). </br>The NRC resident inspectors have been informed.</br>Notified R4DO (Proulx).ave been informed.
Notified R4DO (Proulx).
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00:00:00, 15 May 2019 +
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>.
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03:06:00, 1 April 2019 +
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