| 05-21-2009 | On March 23, 2009 21:00 Central Daylight Time with the station at 100 percent power, inoperability of the containment fan coil unit 'A' was identified. While preparing to remove the fan motor during maintenance, workers saw that the fan was spinning backward and an excessive amount of air was blowing through gaps in the ventilation ductwork. Investigation found the containment fan coil unit backdraft damper not fully closed.
The fan had been in an off/auto condition since November 14, 2008. This condition allowed backflow from the operating containment fan coil unit 'B'. With the fan spinning backward, it is postulated that the fan would trip on overcurrent when started. Following review of the operability of required containment cooling systems since November 14, it was determined that Technical Specifications had been violated numerous times due to inoperability of various combinations of containment cooling system components and the postulated inoperable containment fan coil unit 'A'.
This condition is being reported pursuant to 10 CFR 50.73(a)(2)(i)(B), as a condition which was prohibited by the plant's Technical Specifications, 10 CFR 50.73(a)(2)(ii)(B), as a condition that resulted in the nuclear power plant being in an unanalyzed condition, and since both trains of containment cooling systems were inoperable, this condition is being reported under 10 CFR 50.73(a)(2)(v), for any event & condition that could have prevented the fulfillment.of the safety function of structures or systems that are needed to: (C) Control the release of radioactive material; or (D) Mitigate the consequences of an accident. |
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Event Description:
On March 23, 2009 21:00 Central Daylight Time (CDT) with the station at 100 percent power, inoperability of the containment fan coil unit 'A' [FCU] was identified. While preparing to remove the fan [FAN] motor [MO] during maintenance, workers saw that the fan was spinning backward and an excessive amount of air was blowing through gaps in the ventilation ductwork [DUCT]. The fan had been in an off/auto condition since November 14, 2008. Investigation found the containment fan coil unit backdraft damper [UDMP] not fully closed. This condition allowed backflow from the operating containment fan coil unit 'B'. At the time of discovery there was no immediate reportability since the fan was inoperable and the Technical Specification (TS) Limiting Condition for Operation (LCO) had been entered for the maintenance activity of replacing the fan motor.
Following a review of the operability of required containment cooling systems [BK] since November 2008, it was determined that Technical Specifications had been violated numerous times during this time due to inoperability of various combinations of containment cooling system components and the stuck open containment fan coil unit 'A' backdraft damper. Engineering determined that with the backdraft damper failing to close upon stopping the fan, the containment fan coil unit 'A' would likely have tripped if required to start during an accident from the off/auto condition due to overcurrent.
Per the Updated Safety Analysis Report (USAR) Revision 21, Section 6.4:
"Either of the following combinations of equipment will provide sufficient heat removal capability to maintain the post-accident containment vessel pressure below the design value:
- All four containment fan-coil units - Two containment fan coil units and one internal containment spray pump" The following TS apply to the containment cooling systems:
TS 3.3.c.1.A.3. During power operation or recovery from inadvertent trip, any one of the following conditions of inoperability may exist during the time intervals specified. If OPERABILITY is not restored within the time specified, then within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> action shall be initiated to:
- Achieve HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
- Achieve HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
- Achieve COLD SHUTDOWN within an additional 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.
(i) One containment fancoil unit train may be out of service for 7 days provided the opposite containment fancoil unit train remains OPERABLE.
(ii) One containment spray train may be out of service for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> provided the opposite containment spray train remains OPERABLE.
(iii) The same containment fancoil unit and containment spray trains may be out of service for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> provided their opposite containment fancoil unit and containment spray trains remain OPERABLE.
The last time the containment fan coil unit 'A' was placed to the off/auto position was November 14, 2008 and the backdraft damper has been open since then. A review of the inoperability of the two containment fan coil unit trains (A' and 'B' for one train and 'C' and 'D' for the other train) and the two containment spray pump [BE] trains (`A' and 'B'), show numerous cases where TS 3.3.c.1.A.3 has been violated. Examples were found where both trains of containment fan coil units were inoperable or where the same train containment fan coil unit and containment spray train was out of service with the opposite train inoperable.
� The backdraft damper stuck open due to the damper open assist actuator linkage being out of adjustment.
The upper arm was found on the shaft such that the actuator assist pin would not contact the lever arm attached to the damper and assist in openingithe damper. The lower lever arm was found under the open assist pin rather than above it. This configuration would not aid in opening the damper with the actuator assist function. The lever arm was also founid to be interfering with a bearing mounting stud causing it to restrict movement in the closed position. The backdraft damper was repaired and the LCO was exited on March 26, 2009 at 23:35 CDT.
/This condition is being reported pursuant to 10 CFR 50.73(a)(2)(i)(B), as a condition which was prohibited by the plant's Technical Specifications, 10 CFR 50.73(a)(2)(ii)(B), as a condition that resulted in the nuclear power plant being in an unanalyzed condition, and since both trains of containment cooling systems were inoperable at various times, this condition is being reported under 10 CFR 50.73(a)(2)(v), for any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to: (C) Control the release of radioactive material; or (D) Mitigate the consequences of an accident.
Event and Safety Consequence Analysis:
The backdraft damper stuck open due to the damper open assist actuator linkage being out of adjustment.
The damper is a gravity backdraft damper with an air actuator that assists the damper to the open position.
The actuator does not assist the damper to the closed position. When air is isolated to the damper, the damper acts as a check damper.
The damper has two lever arms on the end of two of the damper blade shafts. The open assist actuator is designed to push on these to assist in'opening the damper. The push pins which assist in opening the damper move out of the way when the actuator is failed closed allowing the damper to cycle as a check damper.
This condition would not impact airflow through the ducting since an emergency discharge damper in the system is not affected by this damper and flowpath. However, with the stopped fan rotating backwards, a potential for a fan trip on a start signal is postulated due to increased starting horsepower requirement and the locked rotor inrush current.
The cooling of containment is provided by two systems: Containment fan coil units and containment spray systems. The containment fan coil units and containment spray system protect containment integrity by limiting the temperature and pressure that could be experienced following a Design Basis Accident. The Limiting Design Basis Accidents relative to containment integrity are the loss-of-coolant accident (LOCA) and steam line break (SLB). During normal operation, the fan coil units are required to remove heat lost from equipment and piping within the containment. In the event of the Design Basis Accident, either of the following combinations will provide sufficient cooling to limit containment pressure to less than design values:
Four fan coil units or two fan coil units plus one containment spray pump.
Due to various containment cooling system components being taken out of service while the damper was in the stuck open position from November through March, both trains of containment cooling were considered inoperable.
The containment air cooling system is designed to keep containment below the design pressure during a design basis event. The containment fan coil nits have minimal impact on large early release frequency because the Kewaunee containment is able t withstand a severe accident for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or more before pressure reaches the containment failure pre sure, which is significantly higher than the design pressure.
Therefore, the risk impact of this event is ve low.
Cause:
The backdraft damper stuck open due to th damper open assist actuator linkage being out of adjustment.
Corrective Actions:
The damper lever arm assist actuator linkage was readjusted to operate correctly.
The containment fan coil unit 'B' backdra t damper was checked and did not have a similar condition. The containment fan coil units 'C' and 'D' da pers are of a different design.
Similar Events:
None.
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| 05000410/LER-2009-001 | Momentary Loss of Control Power to High Pressure Core Spray, Pump Due to Degraded Fuse Block Connection | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | | 05000266/LER-2009-001 | Component Coolina Water PumD Inoperable In Excess of Technical Specification Allowed Completion Time | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000263/LER-2009-001 | Containment Overpressure Not Ensured in the Appendix R Analysis | 10 CFR 50.72(b)(3)(ii), Degraded or Unanalyzed Condition | | 05000250/LER-2009-001 | Procedure Inadequacy Causes Control Room Ventilation Isolation Technical Specification Noncompliance | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000237/LER-2009-001 | Common Mode Failure of Reactor Building Isolation Dampers | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000530/LER-2009-001 | Manual Reactor Trip Due to a Loss of Instrument Air to the Containment Building | | | 05000457/LER-2009-001 | Reactor Trip on Over Temperature Delta Temperature due to a Signal Spike on One Channel With Another Channel Placed in the Tripped Condition for Surveillance Testing | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000413/LER-2009-001 | Both Trains of Chemical and Volume Control, Auxiliary Feedwater and Containment Spray Systems were Inoperable due to a Component Failure | 10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000412/LER-2009-001 | Equipment Operability for Steam Generator Tube Rupture Safety Analysis Not Met | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material
10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident
10 CFR 50.73(a)(2)(vi) | | 05000461/LER-2009-001 | Safety Function Lost Due to Capacitor Failure on Circuit Card | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | | 05000382/LER-2009-001 | Waterford 3 Steam Electric Station 05000382 1 OF 3 | | | 05000370/LER-2009-001 | | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000346/LER-2009-001 | Containment Air Cooler Fans Inoperable Due to Misapplication of Potter and Brumfield Rotary Relays | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000336/LER-2009-001 | Reactor Trip Due to High Pressurizer Pressure | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000305/LER-2009-001 | | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000281/LER-2009-001 | Manual Reactor Trip Initiated to Replace a Rod Control Data Logging Card | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000261/LER-2009-001 | Emergency Diesel Generator Inoperable in Excess of Technical Specifications Allowed Completion Time | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000220/LER-2009-001 | Failure to Implement Required Technical Specification Actions Associated with Failed Surveillance Test | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000389/LER-2009-001 | Unit 2 Main Feedwater Isolation Valves Stroke Time Potentially Affected by Temperature | 10 CFR 50.73(a)(2)(I)(B) | | 05000321/LER-2009-001 | Pump Suction Swap for HPCI and RCIC Non-Conservative With Respect To Technical Specification Requirements | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000334/LER-2009-001 | Surveillance Test Inadvertently Violates Technical Specification 3.6.1 for Containment Operability | 10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000369/LER-2009-001 | III Duke
Energy®
BRUCE H HAMILTON
Vice President
McGuire Nuclear Station
Duke Energy Corporation
MGO1VP / 12700 Hagers Ferry Road
Huntersville, NC 28078
704-875-5333
704-875-4809 fax
bhhamilton@duke-energy.com
June 24, 2009
U.S. Nuclear Regulatory Commission
ATTENTION: Document Control Desk
Washington, D.C. 20555
Subject: Duke Energy Carolinas, LLC
McGuire Nuclear Station, Units 1 and 2
Docket Nos. 50-369, 50-370
Licensee Event Report 369/2009-01, Revision 0
Problem Investigation Process (PIP) M-09-02216
Pursuant to 10 CFR 50.73 Sections (a) (1) and (d), attached
is Licensee Event Report 369/2009-01, Revision 0, regarding
the past inoperability of the Nuclear Service Water System
"A" Trains due to potential for strainer fouling.
This report is being submitted in accordance. with 10 CFR
50.73 (a) (2) (i)- (B), an Operation Prohibited by Technical
Specifications, and 10 CFR 50.73 (a) (2) (v) (B), any Event.
or Condition That Could Have Prevented Fulfillment of the
Safety Function.
This event is considered to be of no significance with
respect to the health and safety of the public. There are
no regulatory commitments contained in this LER.
If questions arise regarding this LER, contact Rick Abbott
at 980-875-4685.
Very truly yours,
Bruce H. Hamilton
Attachment
www.duke-energy.corn m
U.S. Nuclear Regulatory Commission
Date
Page 2
CC: L. A. Reyes, Regional Administrator
•U.S. Nuclear Regulatory Commission, Region.II
Sam Nunn Atlanta Federal Center
•61 Forsyth Street, SW, Suite 23T85
Atlanta, GA 30303
J. H. Thompson, Jr. (Addressee Only)
Senior Project Manager (McGuire)
U.S. Nuclear Regulatory Commission
Mail Stop 0-8G9A
Washington, DC 20555
J. B. Brady
Senior Resident Inspector
U.S. Nucle'ar Regulatory Commission-
McGuire Nuclear Station
B. 0. Hall, Section Chief
Radiation Protection Section
1645 Mall Service Center.
Raleigh, NC 27699
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LICENSEE EVENT REPORT (LER)
1. FACILITY NAME 2. DOCKET NUMBER I 3. PAGE
_McGuire Nuclear Station, . 0369 8 Unit 1 05000- OF
4. TITLE
Nuclear Service Water System (NSWS)d
"A" Trains Past Inoperable when aligned
to the Standby Nuclear Service Water Pond due to'corrosion.
(SNSWP) | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat | | 05000456/LER-2009-001 | Steam Generator Tube Exceeding Plugging Criteria Remained In Service During Previous Cycle | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000395/LER-2009-001 | Inadequate Procedure Results In EDG Not Obtaining Maximum Load Required By Technical Specification | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000336/LER-2009-002 | Reactor Coolant System Pressure Boundary Leakage | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded | | 05000373/LER-2009-002 | Loss of Shutdown Cooling Due to Spurious Closure of the Shutdown Cooling Suction Isolation Valve | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat | | 05000382/LER-2009-002 | Waterford 3 Steam Electric Station 05000382 10OF 4 | | | 05000278/LER-2009-002 | Inoperable 'A' Wide Range Neutron Monitor Results in Condition Prohibited by Technical Specifications | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000287/LER-2009-002 | Unit 3 Trip Due to Generator Phase Differential Lockout | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000263/LER-2009-002 | | | | 05000412/LER-2009-002 | Unacceptable Indications Identified During Reactor Vessel Head Inspection | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded | | 05000354/LER-2009-002 | As Found Values for Safety Relief Valve Lift Setpoints Exceed Technical Specification Allowable | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000346/LER-2009-002 | Vibration Induced Failure of Temperature Instrument Results in Operation above Licensed Power Limit | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000261/LER-2009-002 | Failure to Complete Technical Specifications Required Action Within the Allowed Completion Time | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000334/LER-2009-002 | Feedwater Isolation Initiates Auxiliary Feedwater System During Refueling Shutdown | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2)(v), Loss of Safety Function | | 05000254/LER-2009-002 | Quad Cities Nuclear Power Station Unit 1 05000254 1 OF 5 | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | | 05000305/LER-2009-002 | Steam Exclusion Door Blocked Open During Maintenance Activities | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition
10 CFR 50.73(a)(2)(v), Loss of Safety Function | | 05000250/LER-2009-002 | Turkey Point Unit 3 05000250 1 of 10 | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material
10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown | | 05000220/LER-2009-002 | High Pressure Coolant Injection System Initiation Following a Manual Turbine Trip Due to High Turbine Bearing Vibrations | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000298/LER-2009-002 | Manual Scram On Low Water Level Caused By Turbine Trip From Hydraulic Fluid Leak | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000305/LER-2009-003 | Containment Spray Pump A Inoperable At Degraded Voltage Protection Setpoint | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000395/LER-2009-003 | ..Potential Loss of Residual Heat Removal System Safety Function In Mode 4 Due To An Unanalyzed Condition0 | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition
10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability | | 05000389/LER-2009-003 | RCP 2B2 Lower Seal Cavity Line Leak | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded | | 05000323/LER-2009-003 | Containment Sump Recirculation Valve Position Interlock Failure Due to Inadequate Testing | | | 05000263/LER-2009-003 | | 10 CFR 50.73(a)(2)(v), Loss of Safety Function | | 05000261/LER-2009-003 | Manual Reactor Trip Due to Failure of 'A' Steam Generator Level Module | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000440/LER-2009-003 | Reactor Recirculation Pump Failure Results in Manual Reactor Protection System Actuation | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown | | 05000361/LER-2009-003 | Pressurizer Auxiliary Spray Failed Inservice Test | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat | | 05000457/LER-2009-003 | Drain Procedure for ECCS Suction Line Creates an Unanalyzed Condition Due to Inadequate Configuration Requirements | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition | | 05000237/LER-2009-003 | Emergency Diesel Generator Oil Leak | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
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