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During normal power operations at 100 percent power on Unit 2, both trains of Containment Air Return Fans (CARF) were declared inoperable at 19:28 (EST) on January 9, 2018 due to a common issue with control power fuses. The fuses potentially could not handle the in-rush current upon re-energizing the circuits. This condition resulted in a loss of a reasonable expectation that the Unit 2 Containment Air Return Fans would meet their design safety function and mitigate an accident. This loss of safety function is reportable under 10CFR50.72(b)(3)(v)(D), 8 hour report. The site entered T.S. 3.0.3 at 19:28 and exited at 20:54 when repairs to 2B CARF were completed. 2A CARF repairs are complete. There was no impact on the health and safety of the public or plant personnel. The senior NRC Resident Inspector has been notified. The licensee verified this problem does not affect unit-1.

• * * RETRACTION AT 0939 EST ON 03/08/2018 FROM JUSTIN BLACK TO TOM KENDZIA * * *

A subsequent evaluation determined that the fuses for the Containment Air Return Fans (CARFs) would be able to perform their safety function and were operable at the time of discovery. The limiting safety condition for the fuses is the return to power following a Loss of Offsite Power (LOOP). The evaluation determined that the fuses would satisfy their safety function upon re-energizing the circuits if a LOOP occurred and would not impact the ability of the CARFs to perform their safety function. The subject fuses were replaced on January 9, 2018." The Licensee notified the NRC Senior Resident Inspector. Notified the R2DO (Musser).

Rod L-13 did not function as expected during control rod movement test. This rod is in Shutdown Bank C. When withdrawing this bank, rod L-13 did not withdraw and when the bank was manually inserted, rod L-13 began to withdraw. The (operating) crew went to Enclosure 13.2 of the procedure to deal with the misaligned rods. This enclosure has procedural guidance to open the reactor trip breakers, if desired. The reactor trip breakers were opened and all 211 rods are fully inserted. The reactor was not critical. This activity was performed twice (at the request of reactor engineering). The licensee will remain in Mode 5 (Cold Shutdown) until troubleshooting and repair is completed. The licensee will be notifying the NRC Resident Inspector.

• * * RETRACTION AT 1528 ON 4/26/2011 FROM JAMES DAIN TO MARK ABRAMOVITZ * * *

This notification pertains to Event Number 46709. Based on further investigation, this event is being retracted. The event described in Event Number 46709 involved a control rod malfunction on Unit 2 while in Mode 5, during RCCA movement testing. Specifically, Control Rod 'L-13' in Shutdown Bank 'c' did not move with the bank when the bank was withdrawn from the bottom of the core. When the bank was reinserted to the bottom of the core, L-13 was observed to be 12 steps withdrawn. This condition was corrected by opening the reactor trip breakers which placed L-13 at the bottom of the core. The subsequent troubleshooting plan involved further manipulation of Shutdown Bank 'C' with additional instrumentation on the rod control cabinets. The same anomaly occurred and the reactor trip breakers were again opened. This event (both openings of the reactor trip breakers) was reported to the NRC on 3/30/11 as a valid RPS actuation (8-hour report; 10 CFR 50.72(b)(3)(iv)(A)). The event in question did not result in any consequences, given that the plant was in Mode 5 and not critical. NUREG-1022, Revision 2 states that actuations that need not be reported are those initiated for reasons other than to mitigate the consequences of an event (e.g., at the discretion of the licensee as part of a preplanned procedure). Notwithstanding the issue of whether opening the reactor trip breakers was to mitigate the consequences of an event, NUREG-1022 cites one valid example of actuations that need not be reported, namely if the actuation was 'at the discretion of the licensee as part of a preplanned procedure'. The purpose of the test being conducted was to identify issues with the control rod system. The malfunction that occurred is one of a host of possible issues that could reasonably be expected to occur. Although the test personnel did not go into the test expecting the need to open the reactor trip breakers, the malfunction that occurred resulted in a desire to open the reactor trip breakers in order to restore the plant to the desired configuration. This action was a choice as allowed by the test procedure, and the personnel involved were aware of the result of the action before it occurred. Therefore, the event constituted a 'pre-planned sequence during testing', and was 'at the discretion of the licensee as part of a preplanned procedure.' Based upon the above considerations, the event does not meet the aforementioned criteria for an 8-hour report, and Event Number 46709 is therefore retracted. The licensee has notified the NRC Resident Inspector of this update. Notified the R2DO (Seymour).

The following information was provided by the licensee via facsimile (licensee text in quotes): (The licensee) reduced power on Unit 2 due to a steam leak on a moisture separator reheater vent line. The reactor was manually tripped at 20% reactor power per normal shutdown sequence. All systems and components operated correctly. Unit restart will commence following completion of a planned refueling outage. All rods fully inserted. One steam line secondary PORV lifted and reseated. Decay heat removal is via AFW and steam bypass valves to the main condenser. The steam leak was reported to be on a 2-inch MSR vent line elbow. The licensee has notified the NRC Resident Inspector.

• * * RETRACTION FROM GRADY PICKLER TO HOWIE CROUCH @ 1501 EST ON 3/17/05 * * *

The following information was obtained from the licensee via facsimile (licensee text in quotes): On March 1, 2005, McGuire Unit 2 experienced a steam leak on a two-inch pipe in the heater bleed steam system. In consideration of that leak, Unit 2 was shutdown by manually tripping the reactor. This was reported as an unplanned valid actuation of the reactor protection system (10CFR 50.72 (b) (2)(iv)(B)). Reference Event Report 41453. The manual reactor trip of Unit 2 was not required to mitigate the steam leak. However, in consideration of the steam leak, a decision was made to perform a shutdown of Unit 2 using the normal reactor shutdown procedure. This procedure requires that the control rods be inserted by manually tripping the reactor. As per guidance provided in NUREG-1022, the above actions do not satisfy the criteria for reporting under the requirements of 10CFR 50.72 (b) (2)(iv)(B) or any other reporting criteria. Therefore, McGuire is retracting Event Report 41453. The licensee has notified the NRC Resident Inspector. Notified R2DO (Cahill).