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In Event Notification (EN) 52202 on August … In Event Notification (EN) 52202 on August 25, 2016, Fermi 2 identified an unanalyzed condition related to the inoperability of Mechanical Draft Cooling Tower (MDCT) fans due to nonfunctionality of the associated brakes that occurred on April 6, 2016. The MDCT fan brake is required to prevent fan over speed from a design basis tornado. The MDCT fans are required to support the operability of the Ultimate Heat Sink (UHS) reservoir and associated Emergency Diesel Generators (EDGs). The EN noted that a past operability review was in progress to determine if declaring a MDCT fan inoperable due to a fan brake being nonfunctional resulted in additional instances of unanalyzed conditions within the: three years prior to August 25, 2016.</br>On August 31, 2016 at 1950 EDT, the past operability review identified five additional instances of unanalyzed conditions within the past three years. These five instances are being reported in one EN since they are related and were all discovered and reported within 8 hours. Although these instances are related to the one previously reported in EN 52202, they are being reported in a new EN due to the time elapsed since EN 52202. The MDCT fans and fan brakes are currently operable.</br>1) February 2016 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 0936 EST to 1344 EST on February 25, 2016. This nonfunctionality of the MDCT fan 'A' brake coincided with a High Pressure Coolant Injection (HPCI) system outage in Division 2.</br>2) March 2015 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 1000 EDT on March 23, 2015, until 1447 EDT on April 9, 2015. There is reasonable expectation that the nonfunctionality of the MDCT fan 'A' brake coincided with various Division 2 systems, structures, or components (SSCs) out of service during a forced outage.</br>3) February 2014 - The Division 2 MDCT fan 'B' brake nitrogen bottle pressure was below the required limit from 1118 EST to 1529 EST on February 20, 2014. There is reasonable expectation that the nonfunctionality of the MDCT fan 'B' brake coincided with various Division 1 SSCs out of service during a refueling outage.</br>4) February 2014 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 1747 EST on February 14, 2014, until 1514 EST on February 24, 2014. There is reasonable expectation that the nonfunctionality of the MDCT fan 'A' brake coincided with various Division 2 SSCs out of service during a refueling outage.</br>5) January 2014 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 0915 EST on January 24, 2014, until 1537 EST on January 31, 2014. This nonfunctionality of the MDCT fan 'A' brake coincided with approximately 30 hours where various Division 2 safety-related SSCs were inoperable.</br>The occurrences discussed above resulted in unanalyzed conditions because the plant configuration when equipment in one division was inoperable while a MCDT fan brake was nonfunctional in the opposite division would not support safe shutdown capability in the event of a tornado. This condition is reportable under 10 CFR 50.72(b)(3)(ii)(B), as an event or condition that results in an unanalyzed condition that significantly degrades plant safety. There was no adverse impact to public health and safety or to plant employees.</br>The NRC Resident Inspector has been notified.</br>* * * UPDATE FROM JEFF YEAGER TO JOHN SHOEMAKER AT 1508 EDT ON 10/20/2106 * * * </br>The licensee is RETRACTING item 1 only of the 5 events listed above: 1) February 2016 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 0936 EST to 1344 EST on February 25, 2016. This nonfunctionality of the MDCT fan 'A' brake coincided with a High Pressure Coolant Injection (HPCI) system outage in Division 2.</br>Fermi 2 is retracting item 1 of the 8-hour event notification made on August 31, 2016, at 2332 EDT, (EN #52214). EN #52214 originally reported a non-functionality of the Division 1 MDCT fan 'A' brake on February 25, 2016, as an unanalyzed condition due to it coinciding with a Division 2 High Pressure Coolant Injection (HPCI) system outage. Subsequent engineering evaluation has determined that although the intermediate nitrogen bottle pressure was below its required limit, the pressure in the main nitrogen bottle was sufficient to ensure that the MDCT fan 'A' brake could have performed its intended function in the event of a tornado. Since the MDCT fan 'A' brake was determined to be functional, the MDCT fan 'A', the associated Division 1 UHS reservoir, and the Division 1 EDGs were all operable at that time. Therefore, no unanalyzed condition existed on February 25, 2016. The other four items (2-5) included in EN #52214 are not being retracted and are still considered unanalyzed conditions.</br>The licensee notified the NRC Resident Inspector.</br>Notified R3DO (Orth). Resident Inspector.
Notified R3DO (Orth).
23:50:00, 31 August 2016 +
52,214 +
23:32:00, 31 August 2016 +
23:50:00, 31 August 2016 +
In Event Notification (EN) 52202 on August … In Event Notification (EN) 52202 on August 25, 2016, Fermi 2 identified an unanalyzed condition related to the inoperability of Mechanical Draft Cooling Tower (MDCT) fans due to nonfunctionality of the associated brakes that occurred on April 6, 2016. The MDCT fan brake is required to prevent fan over speed from a design basis tornado. The MDCT fans are required to support the operability of the Ultimate Heat Sink (UHS) reservoir and associated Emergency Diesel Generators (EDGs). The EN noted that a past operability review was in progress to determine if declaring a MDCT fan inoperable due to a fan brake being nonfunctional resulted in additional instances of unanalyzed conditions within the: three years prior to August 25, 2016.</br>On August 31, 2016 at 1950 EDT, the past operability review identified five additional instances of unanalyzed conditions within the past three years. These five instances are being reported in one EN since they are related and were all discovered and reported within 8 hours. Although these instances are related to the one previously reported in EN 52202, they are being reported in a new EN due to the time elapsed since EN 52202. The MDCT fans and fan brakes are currently operable.</br>1) February 2016 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 0936 EST to 1344 EST on February 25, 2016. This nonfunctionality of the MDCT fan 'A' brake coincided with a High Pressure Coolant Injection (HPCI) system outage in Division 2.</br>2) March 2015 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 1000 EDT on March 23, 2015, until 1447 EDT on April 9, 2015. There is reasonable expectation that the nonfunctionality of the MDCT fan 'A' brake coincided with various Division 2 systems, structures, or components (SSCs) out of service during a forced outage.</br>3) February 2014 - The Division 2 MDCT fan 'B' brake nitrogen bottle pressure was below the required limit from 1118 EST to 1529 EST on February 20, 2014. There is reasonable expectation that the nonfunctionality of the MDCT fan 'B' brake coincided with various Division 1 SSCs out of service during a refueling outage.</br>4) February 2014 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 1747 EST on February 14, 2014, until 1514 EST on February 24, 2014. There is reasonable expectation that the nonfunctionality of the MDCT fan 'A' brake coincided with various Division 2 SSCs out of service during a refueling outage.</br>5) January 2014 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 0915 EST on January 24, 2014, until 1537 EST on January 31, 2014. This nonfunctionality of the MDCT fan 'A' brake coincided with approximately 30 hours where various Division 2 safety-related SSCs were inoperable.</br>The occurrences discussed above resulted in unanalyzed conditions because the plant configuration when equipment in one division was inoperable while a MCDT fan brake was nonfunctional in the opposite division would not support safe shutdown capability in the event of a tornado. This condition is reportable under 10 CFR 50.72(b)(3)(ii)(B), as an event or condition that results in an unanalyzed condition that significantly degrades plant safety. There was no adverse impact to public health and safety or to plant employees.</br>The NRC Resident Inspector has been notified.</br>* * * UPDATE FROM JEFF YEAGER TO JOHN SHOEMAKER AT 1508 EDT ON 10/20/2106 * * * </br>The licensee is RETRACTING item 1 only of the 5 events listed above: 1) February 2016 - The Division 1 MDCT fan 'A' brake nitrogen bottle pressure was below the required limit from 0936 EST to 1344 EST on February 25, 2016. This nonfunctionality of the MDCT fan 'A' brake coincided with a High Pressure Coolant Injection (HPCI) system outage in Division 2.</br>Fermi 2 is retracting item 1 of the 8-hour event notification made on August 31, 2016, at 2332 EDT, (EN #52214). EN #52214 originally reported a non-functionality of the Division 1 MDCT fan 'A' brake on February 25, 2016, as an unanalyzed condition due to it coinciding with a Division 2 High Pressure Coolant Injection (HPCI) system outage. Subsequent engineering evaluation has determined that although the intermediate nitrogen bottle pressure was below its required limit, the pressure in the main nitrogen bottle was sufficient to ensure that the MDCT fan 'A' brake could have performed its intended function in the event of a tornado. Since the MDCT fan 'A' brake was determined to be functional, the MDCT fan 'A', the associated Division 1 UHS reservoir, and the Division 1 EDGs were all operable at that time. Therefore, no unanalyzed condition existed on February 25, 2016. The other four items (2-5) included in EN #52214 are not being retracted and are still considered unanalyzed conditions.</br>The licensee notified the NRC Resident Inspector.</br>Notified R3DO (Orth). Resident Inspector.
Notified R3DO (Orth).
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Loss of Safety Function +, 05000341/LER-2016-006, Regarding Inadequate Interpretation of Technical Specifications Related to Mechanical Draft Cooling Tower Fan Brake System Leads to Condition Prohibited by Technical Specifications, Loss of Safety Function, and Unanalyzed +, Regarding Inadequate Interpretation of Technical Specifications Related to Mechanical Draft Cooling Tower Fan Brake System Leads to Condition Prohibited by Technical Specifications + and And Unanalyzed +
00:00:00, 20 October 2016 +
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01:43:59, 2 March 2018 +
23:32:00, 31 August 2016 +
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