| U.S. Nuclear Regulatory Commission
Operations Center Event Reports For
10/20/2016 - 10/21/2016 ** EVENT NUMBERS ** |
 | Power Reactor | Event Number: 52214 | Facility: FERMI
Region: 3 State: MI
Unit: [2] [ ] [ ]
RX Type: [2] GE-4
NRC Notified By: GREG MILLER
HQ OPS Officer: MARK ABRAMOVITZ | Notification Date: 08/31/2016
Notification Time: 23:32 [ET]
Event Date: 08/31/2016
Event Time: 19:50 [EDT]
Last Update Date: 10/20/2016 | Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
| Person (Organization):
BILLY DICKSON (R3DO)
|
| Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | | 2 | N | Y | 74 | Power Operation | 74 | Power Operation | Event Text UNANALYZED CONDITION WITH A POTENTIAL TORNADO
"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.
"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.
"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.
"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.
"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.
"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.
"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.
"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.
"The NRC Resident Inspector has been notified."
* * * UPDATE FROM JEFF YEAGER TO JOHN SHOEMAKER AT 1508 EDT ON 10/20/2106 * * *
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.
"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.
"The licensee notified the NRC Resident Inspector."
Notified R3DO (Orth). |
| Power Reactor | Event Number: 52309 | Facility: PALO VERDE
Region: 4 State: AZ
Unit: [ ] [ ] [3]
RX Type: [1] CE,[2] CE,[3] CE
NRC Notified By: ARMANDO AVILES
HQ OPS Officer: MARK ABRAMOVITZ | Notification Date: 10/20/2016
Notification Time: 00:09 [ET]
Event Date: 10/19/2016
Event Time: 18:30 [MST]
Last Update Date: 10/20/2016 | Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(A) - DEGRADED CONDITION
| Person (Organization):
JOHN KRAMER (R4DO)
|
| Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | | 3 | N | N | 0 | Defueled | 0 | Defueled | Event Text SAFETY INJECTION PIPING WELD FLAW
"While performing a scheduled inservice inspection on a section of safety injection system piping, a flaw was identified in a circumferential weld on the 14 inch safety injection line from the 2A safety injection tank to the 2A reactor coolant loop. Examination results indicate that the flaw constitutes a welding defect that cannot be found acceptable under ASME Section XI, IWB-3600, or Table IWB-3410-1. Further analysis is being conducted.
"The unit had been shutdown for its 19th refueling outage (3R19) on October 8, 2016, at 0000.
"The NRC Resident Inspectors have been informed of this condition."
This piping is required to be operable in modes one through four. |
| Part 21 | Event Number: 52310 | Rep Org: NEXTERA ENERGY SEABROOK, LLC
Licensee: WESTINGHOUSE
Region: 1
City: SEABROOK State: NH
County:
License #:
Agreement: Y
Docket: 05000443
NRC Notified By: KEN BROWNE
HQ OPS Officer: JOHN SHOEMAKER | Notification Date: 10/20/2016
Notification Time: 11:45 [ET]
Event Date: 08/31/2016
Event Time: 11:26 [EDT]
Last Update Date: 10/20/2016 | Emergency Class: NON EMERGENCY
10 CFR Section:
21.21(d)(3)(i) - DEFECTS AND NONCOMPLIANCE
| Person (Organization):
CHRISTOPHER CAHILL (R1DO)
PART 21/50.55 REACT (EMAI)
| Event Text WESTINGHOUSE LIFE LINE D TYPE LAC INDUCTION MOTOR FAILURE
The following Part 21 Report was received from the licensee via facsimile:
10 CFR Part 21 Notification - Westinghouse Life Line D Type LAC Induction Motor Model HSDP 4000V, 700hp.
"This is a non-emergency facsimile notification required by 10 CFR 21.21(d)(3)(i). A written notification in accordance with 10 CFR 21.21(d)(3)(ii) will be provided within 30 days.
"NextEra Energy Seabrook, LLC has determined there is evidence that the Westinghouse Life Line D Type LAC Induction Motor Model HSDP 4000V, 700 hp motors, original to plant construction, have a deviation from expected quality of construction. Of the four motors purchased for Unit 1, Primary Component Cooling Water (PCCW) pumps CC-P-11-D and CC-P-11-C failed after approximately 87,000 hours of operation on July 23, 2008, and November 21, 2008, due to a short caused by localized heating. On June 13, 2015, CC-P-11-B failed due to shorted windings following approximately 32,000 hours of operation. Failure analysis determined the heating was most likely caused by a turn-to-turn short circuit which led directly to the eventual failure of the entire coil-to-ground. Forensic examination identified that the coil insulation was not tightly wrapped, resulting in less than 100% resin penetration throughout the stator insulation system (i.e., voids). The voids led to poor thermal conductivity and localized hot spots that accelerated the degrading of insulation properties over time.
"Based on the failure analysis, it can be concluded that the undesirable coil quality is most likely attributed to workmanship, not motor design. The failure of motor insulation could cause phase-to-phase and phase-to-ground faults which ultimately would prevent motor and PCCW pump from performing their intended safety function.
"The identified condition appears to be a deviation from expected quality of construction and the three failures indicate that the condition is likely applicable to all the motors manufactured at the same time.
"The NRC Senior Resident has been notified." | |