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The following information was provided by the licensee via email: At 2333 EDT on June 12, 2023, the division 2 Mechanical Draft Cooling Tower (MDCT) Fan `D' was declared inoperable due to a trip of the fan while running in high speed. The MDCT fans are required to support operability of the Ultimate Heat Sink (UHS). The UHS is required to support operability of the division 2 Emergency Equipment Cooling Water (EECW) system. The EECW system cools various safety related components, including the High-Pressure Coolant Injection (HPCI) system room cooler. An unplanned HPCI inoperability occurred based on a loss of the HPCI room cooler. The cause of MDCT Fan `D' trip is currently unknown with trouble shooting being developed for remediation of the condition. This report is being made pursuant to 10 CFR 50.72(b)(3)(v)(D) based on an unplanned HPCI inoperability. The NRC Senior Resident Inspector has been notified.

• * * RETRACTION AT 1540 EDT ON 8/8/2023 FROM WHITNEY HEMINGWAY TO BILL GOTT * * *

The purpose of this notification is to retract a previous event notification (EN) 56570 reported on June 13, 2023, at 0602 EDT. The cause of the fan trip was a failed vibration switch. At 0429 EDT on June 14, 2023, the vibration switch was replaced, the MDCT fan "D" was tested satisfactory for operability, and the UHS, emergency diesel generator 13/14, and MDCT were declared operable. Following the initial EN, further analysis of the condition was performed utilizing a previously performed gothic analysis model (to perform HPCI room heat-up calculations) which bounded this condition. Based on the initial conditions at the time of the indication loss, specifically HPCI room and suppression pool temperature, it was determined that the resulting worst case post-accident room temperature was sufficiently low enough to provide margin to HPCI operability without the room cooler in service for the required mission time. No other concerns were noted during the event. HPCI remained operable and there was no loss of safety function. The fan trip did not involve a condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident under 10 CFR 50.72(b)(3)(v)(D). Therefore, the NRC non-emergency 10CFR50.72(b)(3)(v)(D) report was not required and the NRC report 56570 can be retracted, and no licensee event report under 10 CFR 50.73(a)(2)(v)(D) is required to be submitted. The licensee notified the NRC Resident Inspector. Notified R3DO (Nguyen)

The following information was provided by the licensee via email: At 0148 EST on January 4, 2023 it was identified that P4400F603B, Division 2 Emergency Equipment Cooling Water (EECW) Supply Isolation Valve, lost position indication. Division 2 EECW System was declared inoperable due to the potential that this valve may not be capable of performing its safety function to automatically isolate the safety related Division 2 EECW system from the non-safety related Reactor Building Closed Cooling Water (RBCCW) system. Because the Division 2 EECW system provides cooling to the High Pressure Coolant Injection (HPCI) room cooler, HPCI was also declared inoperable; therefore, this condition is being reported as an eight-hour, non--emergency notification per 10 CFR 50.72(b)(3)(v)(D). At 0240 EST, position indication was restored and Division 2 EECW and HPCI was returned to operable following inspection of the associated motor control center (MCC) and testing of the associated fuses. The cause of the loss of indication is under investigation. The Senior NRC resident inspector has been notified.

• * * RETRACTION ON 3/6/23 AT 1740 EST FROM GREGORY MILLER TO KERBY SCALES * * *

The following retraction was received from the licensee via email: The purpose of this notification is to retract a previous Event Notification, EN 56295, reported on 1/4/2023. Following the initial EN, further analysis of the condition was performed utilizing a gothic analysis model to perform HPCI room heat-up calculations. Based on the initial conditions at the time of the indication loss, specifically HPCI room and Suppression Pool temperature, it was determined that the resulting worst case post-accident room temperature was sufficiently low enough to provide margin to HPCI operability without the room cooler in service for the required mission time. No other concerns were noted during the event. Therefore, HPCI remained operable and there was no loss of safety function. The event did not involve a condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident under 10 CFR 50.72(b)(3)(v)(D). Therefore, the NRC non-emergency 10 CFR 50.72(b)(3)(v)(D) report was not required and the NRC report 56295 can be retracted and no Licensee Event Report under 10 CFR 50.73(a)(2)(v)(D) is required to be submitted. The NRC Senior Resident Inspector has been notified. Notified R3DO (Ruiz).

The following information was provided by the licensee via email: At 2108 EDT on August 17, 2022 the Division 2 Mechanical Draft Cooling Tower (MDCT) fans were declared inoperable due to failure of the over speed fan brake inverter. The brakes prevent fan over speed from a design basis tornado. The MDCT fans are required to support operability of the Ultimate Heat Sink (UHS). The UHS is required to support operability of the Division 2 Emergency Equipment Cooling Water (EECW) system. The Division 2 EECW system cools various safety related components, including the High Pressure Coolant Injection (HPCI) room cooler and Division 2 Control Center HVAC (CCHVAC) chiller. An unplanned HPCI inoperability occurred based on a loss of the HPCI Room Cooler. At the time of the event, Division I CCHVAC was inoperable for maintenance (but was running for a maintenance run) and the event caused an inoperability of Division 2 CCHVAC. This resulted in an inoperability of both divisions of CCHVAC. Failure of the Division 2 MDCT Fan brake inverter occurred due to a trip of the DC input breaker. The breaker was reset at 2128 EDT restoring Division 2 UHS Operability. This report is being made pursuant to 10CFR50.72(b)(3)(v)(D) as a condition that at the time of discovery could have prevented the fulfilment of the safety function of structures or systems that are needed to mitigate the consequences of an accident based on a loss of a single train safety system and loss of both divisions of a safety system. The Senior NRC Resident Inspector has been notified

• * * RETRACTION ON 09/08/2022 AT 0856 EDT FROM JEFF MYERS TO MIKE STAFFORD * * *

The following information was provided by the licensee via email: On 8/17/22 at 2108 EDT the Division 2 (Div. 2) mechanical draft cooling tower (MDCT) brake inverter input breaker tripped for an unknown cause. The result of the loss of power was the inoperability of the MDCT fan brakes which impacts the ultimate heat sink (UHS) (TS 3.7.2). The UHS cascades to the EECW (emergency equipment cooling water) (TS 3.7.2) which is a support system for Div. 2 CCHVAC (Control Cell) Chiller A/C system (TS 3.7.4). This resulted in the inoperability of the Div. 2 CCHVAC Chiller. The cause for the breaker to trip is an intermittent electrical transient. Immediate corrective action was to reset the breaker, and the long-term action is to implement a modification to mitigate susceptibility to voltage variations. Div. 1 has implemented this long-term mod and no unexpected trips have occurred to date. Div. 1 CCHVAC Chiller was previously inoperable from equipment issues which was repaired, and the unit was in service for a 24-hour confidence run. Although licensed personnel had not completed the administrative actions for documenting operability during the 24-hour confidence run to monitor parameters, the (post maintenance test) PMT related to the maintenance was already completed, which included a 4-hour run in accordance with surveillance 24.413.01, Div. 1 and Div. 2 Chilled Water Pump and Valve, to verify normal operation and motor current. These PMT's were completed prior to the identified inoperability of the Div. 2 UHS due to the tripped breaker on the brake power supply. At the time of the MDCT brake inverter trip, the Operations' Senior License and the Night Shift Manager were aligned that, although still operating as part of the 24-hour confidence run, the unit was in service and capable of performing its safety function, but the administrative tasks were not completed, the Limited Condition of Operation (LCO) sheet had not been cleared, and no log entries were made. Since the Div. 1 Chiller was, in fact, operable at the time of the trip of the breaker on the inverter, this would allow the use of Technical Specification (TS) 3.0.9 'Barriers'. Per Operations Department Expectation (ODE)-12 `LCOs' (standard guidance and expectations for preparing and implementing an LCO), Operations determined that the MDCT brakes are barriers to a tornado event and TS 3.0.9 could be utilized. By invoking TS 3.0.9, as long as all other supported systems in the other division are operable, Div. 2 supported systems relying upon the UHS can remain operable and the Automatic Depressurization System (ADS) and Reactor Core Isolation Cooling (RCIC) system can be used as backup to the High Pressure Coolant Injection (HPCI) system. Based on this information, there was no loss of safety function with CCHVAC A/C system or HPCI. Therefore, the NRC non-emergency 10CFR50.72(b)(3)(v)(D) report was not required and the NRC report 56054 can be retracted. The NRC Resident Inspector has been notified. Notified R3DO (Orlikowski)

EN Revision Text: HPCI INOPERABLE DUE TO MECHANICAL DRAFT COOLING TOWER FAN BRAKE INVERTER FAILURE At 0935 EST on December 4, 2018, the Division 2 Mechanical Draft Cooling Tower (MDCT) fans were declared inoperable due to failure of the over speed fan brake inverter. The brakes prevent fan over speed from a design basis tornado. The MDCT fans are required to support operability of the Ultimate Heat Sink (UHS). The UHS is required to support operability of the Division 2 Emergency Equipment Cooling Water (EECW) system. The EECW system cools various safety related components, including the High Pressure Coolant Injection (HPCI) system room cooler. An unplanned HPCI inoperability occurred based on a loss of the HPCI Room Cooler. Investigation into why the Division 2 MDCT fan over speed brake inverter failed is in progress. This report is being made pursuant to 10 CFR 50.72(b)(3)(v)(D) based on an unplanned HPCI inoperability. The NRC Resident Inspector has been notified. Fermi 2 is in a 14-day LCO for inoperability of HPCI and a 72-hour LCO for UHS inoperability.

• * * RETRACTION ON 1/30/19 AT 1605 EST FROM CHRIS ROBINSON TO BETHANY CECERE * * *

The purpose of this notification is to retract EN 53772 made on December 4, 2018. Subsequent to the initial notification, the event and site Technical Specifications (TS) were reviewed further. An evaluation determined that TS Limiting Condition for Operation (LCO) 3.0.9 for barriers could be applied to the MDCT fan brakes. As a result of applying TS LCO 3.0.9 to the MDCT fan brakes, it was not necessary to declare the UHS inoperable. With the Division 2 UHS operable on December 4, 2018, the HPCI system was also operable. With HPCI operable, there was no event or condition that could have prevented the fulfillment of a safety function needed to mitigate the consequences of an accident under 10 CFR 50.72(b)(3)(v)(D). Therefore, EN 53772 is retracted and no Licensee Event Report (LER) under 10 CFR 50.73(a)(2)(v)(D) is required to be submitted. The licensee has notified the NRC Resident Inspector. Notified R3DO (Cameron).

At 1040 EDT, Fermi 2 automatically scrammed on RPV (Reactor Pressure Vessel) Level 3 following a loss of the Division 1 Station System Transformer (SST) #64. All control rods fully inserted. HPCI (High Pressure Coolant Injection) and RCIC (Reactor Core Isolation Cooling) automatically started as designed on Reactor Water Level (RWL) 2 and restored RWL. The lowest RWL reached was 101.8 inches (above Top of Active Fuel). HPCI injected for approximately 35 seconds. RWL is currently being maintained in the normal level band with RCIC. No Safety Relief Valves (SRVs) actuated. All isolations and actuations for RWL 3 and 2 occurred as expected. Investigation into loss of SST #64 continues. At the time of the scram, all Emergency Core Cooling Systems (ECCS) and Emergency Diesel Generators (EDGs) were operable, and no safety related equipment was out of service. This report is being made in accordance with 10CFR50.72(b)(2)(iv)(A), any event that results in ECCS discharge into the reactor coolant system as a result of a valid signal and 10CFR50.72(b)(2)(iv)(B), any event that results in the actuation of the Reactor Protection System (RPS) when the reactor is critical. Following the loss of power and reactor scram, the Division 2 EECW (Emergency Equipment Cooling Water) Temperature Control Valve (TCV) controller was in Emergency Manual and maintaining max cooling. Operators placed the controller in Auto and the TCV is controlling normally. The NRC Senior Resident has been notified. Decay heat is being removed via Division 2 steam dumps to the condenser. The plant is in a modified shutdown electric lineup with offsite power available and stable. Emergency diesel generators did automatically start and load.

• * * UPDATE ON 4/14/2018 AT 1838 EDT FROM JEFF MYERS TO HOWIE CROUCH * * *

This update provides additional clarification of the applicable reporting criteria for this event associated with Primary Containment Isolation Actuations. All isolations and actuations for RWL (Groups 4, 13, and 15) and RWL 2 (Groups 2, 10, 11, 12, 14, 16, 17, and 18) occurred as expected. This report is also being made in accordance with 10CFR50.72(b)(3)(iv)(A), any event or condition that results in valid actuation of any systems listed in paragraph (b)(3)(iv)(B): RPS, HPCI, and RCIC. RPV pressure is being maintained by the bypass valves to the main condenser. All actuations that occurred were fully completed and restored. The licensee notified the NRC Resident Inspector. Notified R3DO (Stone).

• * * UPDATE ON 4/15/2018 AT 1950 EDT FROM KELLEY BELENKY TO DAVID AIRD * * *

This update provides additional information regarding the specified system actuations and an additional applicable reporting criteria. The loss of Division 1 Station System Transformer (SST) #64 at 1040 EDT on 4/14/2018 resulted in the automatic initiation of Emergency Diesel Generators (EDG) 11 and 12. The EDGs started as expected and continue to supply their associated busses. This is reportable pursuant to 10CFR50.72(b)(3)(iv)(A), as an event or condition that resulted in a valid actuation of any system listed in paragraph (b)(3)(iv)(B), including EDGs. In addition, the loss of the Division 1 SST #64 resulted in the expected transfer from the normal to alternate power source for the Low Pressure Coolant Injection (LPCI) swing bus, rendering LPCI loop select inoperable. The alternate power source continued to energize the LPCI swing bus throughout the event until the system was realigned to the normal power source at 1239 EDT on 4/14/2018. This condition is reportable pursuant to 10CFR50.72(b)(3)(v)(D). The licensee notified the NRC Resident Inspector. Notified R3DO (Stone).

On January 6, 2016, at approximately 1514 EST, with Fermi 2 in Mode 1 operating at 100 percent reactor thermal power, the East and West Turbine Bypass Valves (TBVs) automatically opened for 3 minutes and 32 seconds in response to the number one High Pressure Turbine Stop Valve (TSV) drifting from full open to 25 percent open. Reactor power was subsequently lowered to 91.0 percent reactor thermal power and the bypass valves closed. Per Technical Specification Bases 3.3.1.1, TBVs must remain shut while reactor thermal power is at or above 29.5 percent to consider the TSV closure and Turbine Control Valve (TCV) fast closure Reactor Protection System (RPS) functions operable. The condition was recognized at the time of the event and the RPS functions were not declared inoperable since the functions were verified to remain enabled. Since the RPS functions were not declared inoperable, Fermi 2 did not report this event within 8 hours of occurrence. However, after further evaluation, it was determined that this event met the reporting criterion. Accordingly, this event is being reported pursuant to 10 CFR 50.72(b)(3)(v)(A). The licensee informed the NRC Resident Inspector. The cause of the High Pressure Turbine Stop Valve drifting was due to an actuator malfunction that has since been corrected. This event was determined to be reportable at 1200 EST on 02/24/16. See EN #51756 for a similar event that occurred on 02/21/16.

• * * UPDATE FROM JEFF GROFF TO STEVEN VITTO ON 03/02/2016 AT 1530 EST * * *

Upon further review, it was determined that this event also meets the reporting criterion of 10CFR50.72(b)(3)(v)(D) for a condition that could have prevented the fulfillment of a safety function of structures or systems that are needed to mitigate the consequences of an accident. Although this event was determined to be reportable at 1200 EST on 02/24/16, it met the reporting requirement on the date of the event (01/06/2016). The licensee informed the NRC Resident Inspector. Notified R3DO (Valos).

On February 21, 2015, at approximately 0030 EST, with Fermi 2 in Mode 1 operating at 100 percent reactor thermal power, the West Turbine Bypass Valve (TBV) automatically opened in response to the number two High Pressure Turbine Stop Valve (TSV) cycling from full open to closed and then to 22 percent open. Reactor power was subsequently lowered to 91.5 percent reactor thermal power and the bypass valve closed. Per Technical Specification Bases 3.3.1.1, TBVs must remain shut while reactor thermal power is at or above 29.5 percent to consider the TSV closure and Turbine Control Valve (TCV) fast closure Reactor Protection System (RPS) functions operable. The condition was recognized at the time of the event and the RPS functions were declared inoperable. The Limiting Condition for Operation was exited at 0031 EST following TBV closure. Since the RPS functions were verified to remain enabled, Fermi 2 did not report this event within 8 hours of occurrence. However, this event was subsequently determined to meet the reporting criterion and is being reported pursuant to 10 CFR 50.72(b)(3)(v)(A). The licensee informed the NRC Resident Inspector. The cause of the High Pressure Turbine Stop Valve cycling was due to a communication card failure that has since been corrected. This event was determined to be reportable at 1200 EST on 02/24/16. See EN #51755 for a similar event that occurred on 01/06/16.

• * * UPDATE FROM JEFF GROFF TO STEVEN VITTO ON 03/02/2016 AT 1530 EST * * *

Upon further review, it was determined that this event also meets the reporting criterion of 10CFR50.72(b)(3)(v)(D) for a condition that could have prevented the fulfillment of a safety function of structures or systems that are needed to mitigate the consequences of an accident. Although this event was determined to be reportable at 1200 EST on 02/24/16, it met the reporting requirement on the date of the event (02/21/2015). The licensee informed the NRC Resident Inspector. Notified R3DO (Valos).

At 1053 (EDT) on April 3, 2013, during the performance of a surveillance test on the Division 2 Emergency Equipment Cooling Water (EECW) system the EECW system was declared inoperable due to the Division 2 EECW makeup pump failing to start during the surveillance. The EECW system cools various safety related components, including the High Pressure Coolant Injection (HPCI) room cooler. A 14 day Limiting Condition for Operation (LCO) was entered for HPCI via (Technical Specification) LCO 3.5.1. Investigation into why the makeup pump did not start is currently in progress. This report is being made pursuant to 10 CFR 50.72 (b)(3)(v)(D) as a condition that at the time of discovery could have prevented the fulfillment of a safety function needed to mitigate the consequences of an accident, based on a loss of a single train safety system. The NRC Resident Inspector has been notified.

• * * UPDATE FROM BRETT JEBBIA TO VINCE KLCO ON 5/28/13 AT 1613 EDT * * *

An evaluation of Event 48886 has determined that the Division 2 Emergency Cooling Water (EECW) system was capable of supporting HPCI Room Cooler and HPCI operation for a period of time in excess of that required to perform the required safety functions as assumed in the accident analysis. Therefore, this event is retracted. The licensee notified the NRC Resident Inspector. Notified the R3DO (Orth).

On January 28, 2009 at 0730 the Division 2 Emergency Equipment Cooling Water System (EECW) was declared inoperable due to a blown control power fuse in the bucket for the P4400F604 - Div 2 EECW Supply to Control Rod Drive (CRD) pumps. This is a normally open valve and is required to close upon EECW initiation to remove non-essential loads. The blown control power fuse would have prevented this action from occurring. The ECCW System cools various safety related components including the High Pressure Coolant Injection (HPCI) System Area Cooler. An unplanned HPCI inoperability occurred due to the Division 2 EECW inoperability based on a loss of the HPCI System Area Cooler. A 14 day Limiting Condition for Operation (LCO) was entered for HPCI per LCO 3.5.1. The control power fuse was replaced, EECW and HPCI were declared operable, and LCO 3.5.1 exited on January 28, 2009 at 1025. This report is being made pursuant to 10CFR50.72(b)(3)(v)(D) as a condition that at the time of discovery could have prevented the fulfillment of a safety function needed to mitigate the consequences of an accident, based on loss of a single train safety system. The NRC Resident Inspector has been notified.

• * * RETRACTION FROM JIM KONRAD TO DONALD NORWOOD AT 1449 ON 3/11/09 * * *

The As-Found condition of the Division 2 Emergency Equipment Cooling Water (EECW) Control Rod Drive (CRD) Pump Supply Valve and High Pressure Coolant Injection (HPCI) System Room Cooler were evaluated. The HPCI System Room Cooler was operable with P4400-F604, Division 2 EECW to the CRD supply valve open. Based on an Engineering evaluation of EECW flow during a Loss of Coolant Accident (LOCA) and Non-LOCA conditions with the valve open, there is adequate flow margin in the EECW system. The HPCI Room Cooler had adequate cooling flow to perform its design function. The HPCI room temperature would have been maintained below the HPCI equipment room high temperature isolation setpoint. Additionally, plant procedures provide directions for bypassing the HPCI equipment room high temperature trip. Consequently, there was no loss of HPCI safety function. Declaring HPCI inoperable was conservative and based on initial considerations. Therefore, event notification 44811 is retracted. The Licensee notified the NRC Resident Inspector. Notified R3DO (Lara).

While performing Div. 1 & 2 Emergency Equipment Cooling Water (EECW)/Emergency Equipment Service Water (EESW) Valve Lineup Verification surveillance on 12/22/05, the temperature control valve (TCV) on both divisions of EECW were found to be approximately 95% open rather than their required full open position. The system design requires that the TCV, or the associated TCV bypass valve, be in the full open position during system startup to avoid a potentially damaging pressure transient from occurring. Both divisions of EECW and all supported systems (including HPCl, both divisions Core Spray, and both divisions of RHR) were declared INOPERABLE at 2225 EST. Multiple LCO Required Actions were entered, including entry into LCO 3.0.3. At 2250 EST, Div. 1 EECW was restored to OPERABLE status by fully opening the TCV bypass valve and isolating the TCV, and LCO 3.0.3 was exited. At 2252 EST, Div. 2 EECW was restored to OPERABLE status by fully opening the TCV bypass valve and isolating the TCV, and all associated LCO Required Actions were exited. Reactor power remained at 100% throughout the event. The NRC resident inspector has been notified. This report is being made pursuant to 10CFR50.72(b)(3)(ii)(B) as an unanalyzed condition and 10CFR50.72(b)(3)(v)(D) as a condition that at the time of discovery could have prevented the fulfillment of a safety function needed to mitigate the consequences of an accident. The licensee is investigating the cause of the valve not being fully open. The licensee notified the NRC Resident Inspector.

• * * UPDATE PROVIDED BY YEAGER TO ROTTON AT 1524 ON 01/05/06 * * *

This is a retraction of NRC Event #42224. Based on further engineering review, it is concluded that no potential damage from a pressure transient would occur as a result of the TCV being approximately 95% open. System startup pressure transient concerns reflected in the operating procedures originated from a previously-experienced pressure transient resulting from void collapse against a closed TCV. System startup with the as-found TCV position still provides a sufficiently-open flow path to preclude void collapse against a closed boundary. Additionally, Engineering has determined that system operation with a 90% open TCV would have no significant impact on total system flow and the cooling function. Therefore, both divisions of EECW and all other supported systems (including HPCI, both divisions of Core Spray, and both divisions of RHR) were operable with the TCV in the approximately 95% open position. The licensee notified the NRC Resident Inspector. Notified R3DO (Ring).

With the plant in Mode 1 and 100% reactor power at 2043 (EDT) on September 30, 2003, while shifting divisions of Control Center HVAC (CCHVAC), the Division 1 chiller failed to start and Division 1 CCHVAC was declared INOPERABLE. At 2050, a restart of Division 2 CCHVAC was attempted and the Division 2 chiller failed to start. Division 2 CCHVAC was declared INOPERABLE, and the plant entered LCO 3.0.3 as required by LCO 3.7.4 Condition D. Plant shutdown was initiated at 2146. Division 1 CCHVAC was declared OPERABLE at 2315, and LCO 3.0.3 was exited. Plant shutdown was terminated at 2315 with the reactor at 84% power. Division 2 CCHVAC remains INOPERABLE and under investigation, with plant operating under LCO 3.7.4 Condition A. Plans are to return to 100% reactor power. All ECCS systems remained OPERABLE during this event. The NRC Resident Inspector has been notified. This report is being made pursuant to 10 CFR 50.72(b)(2)(i) and 10 CFR 50.72(b)(3)(v)(D).

• * * UPDATE 1428 EDT ON 10/20/03 FROM JEFF YEAGER TO S. SANDIN * * *

The licensee is retracting the notification required per 10 CFR 50.72(b)(3)(v) based on the following: At 2050 hours on September 30,2003 with the plant operating at 100 percent reactor power air conditioning chillers for both divisions of the Control Center Air Conditioning System failed to start. Technical Specification (TS) LCO 3.0.3 was entered as directed by LCO 3.7.4, Control Center Air Conditioning System, Condition D.1 and a plant shutdown initiated at 2146 hours. Notification was made in accordance with 10 CFR 50.72(b)(2)(i), a Plant Shutdown Required by Technical Specifications. The chiller for Division 1 Control Center Air Conditioning System was started after approximately one hour and subsequently declared operable at 2315 hours. TS 3.0.3 was exited and power reduction was terminated at 84 percent reactor power. Notification was also made in accordance with 10 CFR 50.72(b)(3)(v), Event or Condition that Could Have Prevented Fulfillment of a Safety Function. Investigation revealed an oil pressure permissive was not met for start of the chiller due to a small amount of air leaking into a pressure switch while shutdown. This delayed meeting the oil pressure permissive for starting the chiller. Subsequent start attempts removed the air, allowing the pressure permissive to be met and the chiller to be restarted. This restart of the chiller was accomplished from the main control room in accordance with plant procedures. Therefore, Division 1 Control Center Air Conditioning was capable of performing its intended function. This condition is therefore not reportable under 10 CFR 50.72(b)(3)(v). The original notification, Event Number 40210, is retracted. The licensee informed the NRC Resident Inspector. Notified R3DO (Jim Creed).