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Event Notification Report for September 29, 2016

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
09/28/2016 - 09/29/2016

** EVENT NUMBERS **


52267 52269

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Power Reactor Event Number: 52267
Facility: ARKANSAS NUCLEAR
Region: 4 State: AR
Unit: [ ] [2] [ ]
RX Type: [1] B&W-L-LP,[2] CE
NRC Notified By: ALBERT MARTIN
HQ OPS Officer: STEVE SANDIN
Notification Date: 09/28/2016
Notification Time: 09:46 [ET]
Event Date: 09/28/2016
Event Time: 07:45 [CDT]
Last Update Date: 09/28/2016
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(i) - PLANT S/D REQD BY TS
Person (Organization):
JEREMY GROOM (R4DO)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
2 N Y 100 Power Operation 65 Power Operation

Event Text

UNIT 2 SHUTDOWN REQUIRED BY TECHNICAL SPECIFICATIONS DUE TO INOPERABLE DIESEL GENERATOR

"On September 16, 2016, at 0036 [CDT], during a 24-hour Technical Specification (TS) endurance run, the Arkansas Nuclear One, Unit 2 (ANO-2) red train Emergency Diesel Generator (EDG) became inoperable when its inboard generator bearing failed. ANO-2 TS 3.8.1.1, 'AC Sources', requires an inoperable EDG to be restored to service within 14 days or actions to place the unit in a shutdown condition initiated.

"It has been determined that repair options cannot be completed within the Allowed Outage Time (AOT) due to unforeseen circumstances which evolved during recovery efforts. At 0745 [CDT], ANO-2 initiated plant shutdown due to the inability to restore the red train EDG. ANO-2 will be shutdown and cooled down to Mode 5."

The licensee informed the NRC Resident Inspectors.

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Part 21 Event Number: 52269
Rep Org: WECTEC LLC
Licensee: CB&I LAURENS
Region: 1
City: CHARLOTTE State: NC
County:
License #:
Agreement: Y
Docket:
NRC Notified By: CURTIS CASTELL
HQ OPS Officer: VINCE KLCO
Notification Date: 09/28/2016
Notification Time: 14:57 [ET]
Event Date: 09/28/2016
Event Time: [EDT]
Last Update Date: 09/28/2016
Emergency Class: NON EMERGENCY
10 CFR Section:
21.21(d)(3)(i) - DEFECTS AND NONCOMPLIANCE
Person (Organization):
BINOY DESAI (R2DO)
PART 21/50.55 REACT (EMAI)

Event Text

PART 21 REPORT REGARDING PIPE SPOOL FLANGES FOR VOGTLE UNIT 3

The following was excerpted from an email received from WECTEC LLC:

"Nature of the defect or failure to comply and the safety hazard which is created or could be created by such defect or failure to comply.

"The two flanges identified with deviations on Passive Core Cooling System pipe spools for the Vogtle Unit 3 AP1000r project had incorrect raised-face dimensions. This appears to have been caused by the two flanges being transposed due to an inadvertent fabrication error that occurred at the pipe spool supplier's facilities (CB&I Laurens). The error was subsequently discovered after delivery to the fabrication facility (Aecon Industrial).

"This error resulted in conditions where the two flanged connections would not have met the design configuration. If the flanged connections had been assembled in the delivered configuration, it is not known if system integrity and operability would have been maintained during operation. The incorrect configuration could have also led to subsequent failure after installation and operation. Hydrostatic testing of these connections is required, but had not yet been performed because the condition was discovered prior to the assembly and testing of these portions of the system. The condition is being corrected prior to the performance of that hydrostatic testing, therefore it is not known if the flanges in the incorrect configuration would have been able to pass hydrostatic testing.

"Due to the possibility that system integrity and operability could have been impacted by the use of the incorrect flanges, it has been conservatively concluded that this condition should be reported under 10 CFR Part 21. This conservative conclusion is based on the possibility that the Passive Core Cooling System could have been adversely impacted by the identified deviations, if the deviations had been left uncorrected.

"The corrective action which has been, is being, or will be taken; the name of the individual or organization responsible for the action; and the length of time that has been or will be taken to complete the action.

". . . The flange configuration was corrected and the Q223 Mechanical Module was delivered to the Vogtle Unit 3 site on September 23, 2016. A corrective action report has been entered into the Westinghouse/WECTEC system to further evaluate the circumstances that led to the identified deviations."

Page Last Reviewed/Updated Thursday, September 29, 2016
Thursday, September 29, 2016