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ENS 5224819 September 2016 12:21:00This is a non-emergency facsimile notification required by 10 CPR 21.21(d)(3)(i). A written notification in accordance with 10 CFR 21.21(d)(3)(ii) will be provided within 30 days. Duke Energy McGuire Nuclear Station (McGuire) has determined there is evidence of a departure from technical requirements, a Deviation, associated with Joslyn Clark overload heater element Part Number (PIN) 2455. This part was procured in accordance with the Duke Energy Commercial Grade Program (CGP) and dedicated for use in safety related applications. Three of 18 overload heater elements, purchased as a lot, had insufficient top weld material. One failed in-service during a post maintenance test, the second and third failed during a visual and mechanical inspection. An extent of condition review inspected over 500 similar Joslyn Clark overload heater elements. No other inventory was found with a top weld issue. These overload heater elements are used in motor starters for the Emergency Diesel Generator (EDG) ventilation fans. This condition was discovered during post maintenance testing of the 2A EDG on July 27, 2016. None of the suspect overload heater elements were installed in Operable EDG ventilation fan motor starters. The dedicated overload heater elements, from this lot, were not transferred or sold to any third party customers. Specialty Product Technologies, manufacturer of the Joslyn Clark overload heater elements, has been notified of the deviation and is investigating their welding process. The Evaluation of the deviation determined that a Substantial Safety Hazard would have been created if the overload heater elements were installed and left uncorrected. The NRC Senior Resident Inspector has been notified.
ENS 4877521 February 2013 12:49:00At 0957 EST on 02/21/13, Unit 1 Reactor automatically tripped from 100% power, due to a turbine trip. The turbine trip was caused by a loss of both main feedwater (MFW) pumps. The 1A motor driven auxiliary feedwater (AFW) pump auto started to feed the "A" and "B" Steam Generators (S/G). The 1B motor driven AFW pump was unavailable due to planned maintenance, so the turbine driven AFW pump was manually started to feed the "C" and "D" S/Gs. The reactor trip was uncomplicated. All control rods fully inserted. Decay heat removal is to the main condenser via the turbine bypass valves. There was no primary to secondary leakage. Electrical buses are being supplied via offsite power. Steam generator levels are being returned to normal and MFW has been reset and is available. All other plant systems functioned as designed during and after the reactor trip. There is no impact on Unit 2. There is no impact on the health and safety of the public. The loss of the MFW pumps is still under investigation. The licensee has informed the NRC Resident Inspector.
ENS 4818513 August 2012 19:10:00Duke Energy notified the NC Wildlife Resource Commission of dead catfish in the vicinity of the McGuire low level intake. Notification was made on 8/13/12 at 1630 EDT. In addition, the NC Dept. of Environment and Natural Resources will be notified. The dead fish are suspected to have been caused by increasing lake temperature and decreased oxygen levels, which is common during the late summer. The NRC Resident Inspector will be notified.
ENS 4670930 March 2011 07:01:00

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).

ENS 4562713 January 2010 02:24:00The A-YC chiller (was) shutdown and tagged for yearly inspection and work. The B-YC chiller has developed a refrigerant leak and has been declared inoperable. This places both Unit 1 and Unit 2 in Tech Spec 3.0.3. Both units will have to be in Mode 3 within 7 hours; Mode 4 within 13 hours; and 37 hours to be in Mode 5. 3.0.3 was declared at 2332 on 1/12/2010. The event time is when Unit 1 began load reduction. Unit 2 will commence load reduction at 0230. The licensee notified the NRC Resident Inspector.
ENS 439584 February 2008 11:44:00A leak in the final holdup pond has resulted in a release of treated wastewater to the environment. North Carolina Department of Environment and Natural Resources (has) been notified. The volume of the leak was approximately 100,000 gallons and the leak was to groundwater. The licensee has sampled the wastewater for tritium and determined that the activity was below reporting limits. The licensee has notified the NRC Resident Inspector.
ENS 4221117 December 2005 03:45:00'A' Steam Generator hi/hi level caused a turbine trip which in turn caused a Unit 1 reactor trip. The hi/hi steam generator level also caused both feedwater pumps to trip which caused the auxiliary feedwater pumps to auto-start. The hi/hi level also caused a feedwater isolation. Appropriate emergency procedures have been implemented and the plant is currently stable. All control rods fully inserted on the trip. Offsite power is available and powering safety related buses. The emergency diesel generators are available if required. There are no known primary to secondary leaks in the steam generators. The licensee will notify the NRC Resident Inspector.