12-21-2012 | On October 29, 2012 at 21:00, Nine Mile Point Unit 2 (NMP2) was operating at 100 percent power when an automatic actuation of the Division I Emergency Diesel Generator ( EDG) 2EGS*EG1 occurred due to the loss of a 115 kV off-site power source (Line 5).
High winds from the remnants of Hurricane Sandy caused a lightning mast maintained by grid operator National Grid to fall in the Scriba substation in close proximity to the 'A' bus, causing a fault which actuated protective relaying and isolated the 'A' bus. Line 5, the 115 kV offsite power source for Division I, was de-energized when the breaker opened to isolate the fault on the 'A' bus, leading to the automatic actuation of the Division I EDG.
Following the event, the unit continued to operate at 100 percent power and Line 5 was restored at 03:26 on October 30, 2012. The EDG was secured and placed in standby at 04:47 on October 30, 2012.
This event is reportable in accordance with 10 CFR 50.73 (a)(2)(iv)(A), as an automatic actuation of an Emergency Diesel Generator (EDG).
The cause of the lightning mast failure was a horizontal crack above the weld between the base plate and the bottom of the pole. Corrective actions taken include removal of the failed lightning mast and external and internal visual inspections of the remaining lightning masts in the Scriba substation. |
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I. DESCRIPTION OF EVENT
A. PRE-EVENT PLANT CONDITIONS:
Prior to the event, Nine Mile Point Unit 2 (NMP2) was operating at 100 percent rated thermal power, with no inoperable systems affecting this event.
B. EVENT:
At approximately 21:00 on Monday October 29, 2012, with Nine Mile Point Unit 2 (NMP2) in Mode 1 Run, the unit experienced an automatic actuation of the Division I Emergency Diesel Generator (EDG) due to the loss of a 115 kV off-site power source (Line 5) associated with the Division I onsite emergency power distribution system.
The loss of Line 5 occurred due to the 'A' 345 kV offsite power source located in the Scriba substation being de-energized. High winds from the remnants of Hurricane Sandy caused a lightning mast maintained by grid operator National Grid to fall in the Scriba substation in close proximity to the 'A' bus, causing a fault which actuated protective relaying and isolated the 'A' bus. Line 5, the 115 kV offsite power source for Division I, is fed by the 'A' bus and was de-energized when the breaker opened to isolate the fault on the 'A' bus, leading to the automatic actuation of the Division I EDG. Following the event, the unit continued to operate at 100 percent power and Line 5 was restored at 03:26 on October 30, 2012. The Diesel generator was secured and placed in standby at 04:47 on October 30, 2012.
This event also affected Nine Mile Point Unit 1 (NMP1). The event was sensed by NMP1, NMP2, and James A. Fitzpatrick, as the output of all three units is routed through the Scriba switchyard.
This event is reportable in accordance with 10 CFR 50.73 (a)(2)(iv)(A), as an automatic actuation of an Emergency Diesel Generator (EDG). The NRC was notified in accordance with 10 CFR 50.72(b)(3)(iv)(A) on October 30, 2012 at 03:35 (Event Number 48456).
C. INOPERABLE STRUCTURES, COMPONENTS, OR SYSTEMS THAT CONTRIBUTED TO THE
EVENT:
At the time of the event, there were no inoperable Systems, structures, or components (SSCs) that contributed to the event.
D. DATES AND APPROXIMATE TIMES OF MAJOR OCCURRENCES:
October 29, 2012 21:00 Loss of Line 5, diesel generator automatically initiates and energizes its bus.
`A' 345kV bus in the Scriba switchyard is de-energized.
Entered Technical Specification (TS) 3.8.1 Condition A for one offsite circuit inoperable.
Feedwater level control valves 2FWS-LV10A, B, and C actuators locked up.
21:08 2FWS-LV10A is reset. Level Control is in manual.
21:35�2FWS-LV10B placed in automatic control.
October 30, 2012 01:09�Notified by power control that the 'A' 345 kV bus in Scriba switchyard has been re- energized.
03:26�Line 5 is restored and is connected in parallel with the Division I diesel generator. Line 5 is operable. Exited TS 3.8.1 condition A.
04:47�Division I Diesel is secured and is in standby.
E. OTHER SYSTEMS OR SECONDARY FUNCTIONS AFFECTED:
The fault in the 'A' 345 kV offsite power source also caused a voltage transient and NMP2 experienced a feedwater level control lockup due to the electrical transient, requiring operators to take manual control.
Reactor pressure vessel level rose slightly, however no Emergency Core Cooling Systems actuated and operators returned feedwater level control to automatic.
F. METHOD OF DISCOVERY:
On October 29, 2012, at 21:00, Operators noted that the 'A' 345 kV Bus was de-energized, leading to a trip of the 115 kV supply line and a loss of offsite power (Line 5).
G. MAJOR OPERATOR ACTION:
■ Entered Special Operating Procedure (SOP) for Loss of offsite power and stabilized the service water system.
■ Entered TS 3.8.1 condition A for one offsite circuit inoperable.
■ Entered SOP for Feedwater Failure and Feedwater Level Control placed in manual mode.
H. SAFETY SYSTEM RESPONSES:
The Division I Emergency Diesel Generator automatically actuated due to the loss of Line 5 and energized its bus.
II. CAUSE OF THE EVENT:
The cause of this event was the failure of the lightning mast which fell in close proximity to the 'A' 345 kV bus.
This caused a fault in the 'A' bus and the subsequent trip of the 115 kV offsite power source (Line 5) and the Division I diesel actuation.
The cause of lightning mast failure was a horizontal crack above the weld between the base plate and the bottom of the mast. The crack propagated around the circumference of the pole just above the base, leading to the lightning mast's failure during the high winds experienced on October 29, 2012.
This event was entered into the Nine Mile Point (NMP) corrective action program as condition report CR-2012- 009832.
III. ANALYSIS OF THE EVENT:
The event is reportable in accordance with 10 CFR 50.73 (a)(2)(iv)(A), as an automatic actuation of an Emergency Diesel Generator (EDG).
There were no systems inoperable and no system failures related to this event. There were no actual safety consequences from this event. The onsite emergency or safety-related ac power system includes the standby ac power system consisting of the standby diesel generators that feed the safety-related loads in case of loss of offsite power (LOOP). The onsite emergency ac power system is divided into three physically separate and electrically independent divisions, any two out of three divisions being capable of bringing the plant to safe shutdown in case of a loss-of-coolant accident (LOCA) or any other Design Basis Accident (DBA). The emergency ac power system is normally energized from offsite power sources. In case of a LOOP, this system is energized by the standby diesel generators.
During the event, the normal power source for one division of the onsite emergency power distribution system was tripped when a lighting mast fell in the Scriba switchyard. A fault in the 'A' offsite power source led to the loss of Line 5 and as a result, the diesel generator actuated automatically as designed and accelerated to rated speed, voltage, and frequency to energize the safety-related loads. The unit was operating at steady-state 100 percent power prior to and following the event. The event did not occur concurrently with a LOCA or DBA, and did not require the actuation of any safety related equipment required to mitigate an accident. Had the high winds also de-energized the remaining 115 kV offsite power source, the Division II and Division III diesel generators would have been available to power their associated safety-related loads.
During the event, NMP2 also experienced a feedwater level control lockup that required operators to take manual control. No Emergency Core Cooling Systems actuated, and operators returned feedwater level control to automatic.
Based on the above considerations, it has been concluded that the safety significance of this event is low, and the event did not pose a threat to the health and safety of the public or plant personnel.
This event does not affect NRC Reactor Oversight Process (ROP) Performance Indicators.
IV. CORRECTIVE ACTIONS:
A. ACTION TAKEN TO RETURN AFFECTED SYSTEMS TO PRE-EVENT NORMAL STATUS:
1. The failed lightning mast has been removed from service by National Grid and will be replaced.
B. ACTION TAKEN OR PLANNED TO PREVENT RECURRENCE:
1. All remaining lightning masts in the Scriba switchyard were visually inspected by National Grid. No other defective masts were found.
2. Interior inspections of the lightning masts in the Scriba switchyard were performed with a digital inspection camera by National Grid.
3. All lightning masts in the NMP1 and NMP2 switchyards were visually inspected. No defective masts were found.
V. ADDITIONAL INFORMATION:
A. FAILED COMPONENTS:
There were no failed components that contributed to this event.
B. PREVIOUS LERs ON SIMILAR EVENTS:
NMP1 LER 2008-001, Loss of offsite Power due to an equipment malfunction. On May 13, 2008, at 08:06, with Nine Mile Point Unit 1 (NMP1) operating at 100% steady state reactor power and one of two 115 kV offsite power lines (Line 1) out of service for planned maintenance, a loss of the second 115 kV offsite power line (Line 4) occurred. Line 4 is a shared line with the James A. Fitzpatrick Nuclear Power Plant. As a result of the loss of Line 4, both emergency diesel generators auto-started and commenced carrying emergency loads as designed. The cause for the loss of Line 4 was external to Nine Mile Point (NMP) and was determined to be a switchyard equipment malfunction at the James A. Fitzpatrick Nuclear Power Plant switchyard.
C. THE ENERGY INDUSTRY IDENTIFICATION SYSTEM (EIIS) COMPONENT FUNCTION
IDENTIFIER AND SYSTEM NAME OF EACH COMPONENT OR SYSTEM REFERRED TO IN THIS
LER:
COMPONENT� IEEE 803� IEEE 805
COMPONENT IDENTIFIER SYSTEM IDENTIFICATION
Lightning Mast� LAR� FK Diesel Generator DG NA Emergency AC Power System� NA� EK Feedwater Level Control System NA JB Reactor Pressure Vessel� RPV� NA
None
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05000413/LER-2012-001 | | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000327/LER-2012-001 | Unanalyzed Condition Affecting Essential Raw Cooling Water System due to External Flooding | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition | 05000388/LER-2012-001 | Two Control Room Floor Cooling Systems Inoperable | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000395/LER-2012-001 | Vice President, Nuclear Operations 803.345.4342 August 3, 2012SCE~r .so A SCANA COMPANY Document Control Desk U. S. Nuclear Regulatory Commission
Washington, DC 20555
Dear Sir / Madam: Subject:VVIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 LICENSEE EVENT REPORT (LER 2012-001-01) CORE EXIT THERMOCOUPLES & REACTOR WATER LEVEL INDICATION SYSTEM INOPERABLE DUE TO AN INADEQUATE MAINTENANCE PROCEDURE Attached is Licensee Event Report (LER) No. 2012-001-01 for the Virgil C. Summer Nuclear Station Unit 1. This revised report describes a condition where Core Exit Thermocouples and Reactor Water Level Indication System would not be operable for accident monitoring. This report is submitted in accordance with 10 CFR 50.73(a)(2)(i)(B). This letter and attached LER contain no new commitments and no revisions to existing
commitments.
Should you have any questions, please call Bruce Thompson at (803) 931-5042. Very truly yours, Dal Thomas D. Gatlin TS/TDG/jw
Attachment
c: K. B. Marsh P. Ledbetter S. A. Byrne J. C. Mellette J. B. Archie EPIX Coordinator N. S. Carps K. M. Sutton J. H. Hamilton INPO Records Center R. J. White Marsh USA, Inc. W. M. Cherry R. J. Schwartz V. M. McCree NSRC R. E. Martin RTS (CR-11-01807) NRC Resident Inspector FileV(818.07) M. N. Browne PRSF (RC-12-0116) V fALVirgil C. Summer Station • Post Office Box 88 .Jenkinsville, SC • 29065 • F (803) 345-5209 1 NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013 (10-2010) Estimated burden per response to comply with this mandatory collection request: 80 hours.0Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the FOIA/Privacy Section (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by Internet e-mail to infocollects.resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management andLICENSEE EVENT REPORT (LER) Budget, Washington, DC 20503. If a means used to impose an information(See reverse for required number of collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, thedigits/characters for each block) information collection. 1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE Virgil C. Summer Nuclear Station Unit 1 05000 395 1 OF 5 4. TITLE Core Exit Thermocouples & Reactor Water Level Indication System Inoperable due to Inadequate Maintenance Procedure | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000397/LER-2012-001 | DG-3 Inoperable for Longer than Allowed by TS Due to Failed Governor 05000 | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000410/LER-2012-001 | Forced Shutdown Due to an Increase in Drywell Leakage in Excess of Technical Specifications Limit | 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown | 05000289/LER-2012-001 | Single Condition Making Independent Trains Inoperable | 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability | 05000286/LER-2012-001 | Common Cause Inoperability of Both Trains of Motor Driven Auxiliary Feedwater (AFW) Pumps Due to Inability to Control AFW Regulating Valves After Isolation of Nitrogen Backup | 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability | 05000265/LER-2012-001 | Main Steam Isolation Valve Local Leak Rate Test Exceeds Technical Specifications Limit | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000456/LER-2012-001 | Two Main Steam Safety Valves Failed Pre-outage Setpoint Testing Due to Abnormal Spring Geometry | 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000261/LER-2012-001 | Technical Specification Required Plant Shutdown Due to Missed Surveillance and Operation Prohibited by Technical Specifications | 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 | 05000483/LER-2012-001 | Modification Implementation Error Adversely Impacted the Containment Cooling System | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000250/LER-2012-001 | Containment Concrete Thickness At Spalled Patch Does Not Meet Technical Specification Design Value | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000414/LER-2012-001 | Carolinas Duke Energy Carolinas, LLC 4800 Concord Rd. York, SC 29745 803-701-4251 December 20, 2012 U.S. Nuclear Regulatory Commission
Attention: Document Control Desk
Washington, D.C. 20555
Subject:�Duke Energy Carolinas, LLC (Duke Energy)
Catawba Nuclear Station, Units 1 and 2
Docket Nos. 50-413 and 50-414
Licensee Event Report 414/2012-001
Pursuant to 10 CFR 50.73(a)(1) and (d), attached is Licensee Event Report 414/2012-001,
Revision 0 entitled, "Diesel Generator (DG) 2B Was Unknowingly inoperable from 09/28/12 to
10/23/12 Due to Failed Tachometer Relay Power Supply".
This report is being submitted in accordance with 10 CFR 50.73(a)(2)(i)(B), 10 CFR
50.73(a)(2)(ii)(B), and 10 CFR 50.73(a)(2)(v)(A)-(D).
There are no regulatory commitments contained in this letter or its attachment. This event is considered to be of no significance with respect to the health and safety of the
public.
If there are any questions on this report, please contact L.J. Rudy at (803) 701-3084. Kelvin Henderson LJR/s Attachment www. duke-energy. corn Document Control Desk Page 2 December 20, 2012 xc (with attachment): V.M. McCree Regional Administrator U.S. Nuclear Regulatory Commission - Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, GA 30303-1257 J.H. Thompson (addressee only) NRC Project Manager U.S. Nuclear Regulatory Commission Mail Stop 8-G9A 11555 Rockville Pike Rockville, MD 20852-2738 G.A. Hutto, III NRC Senior Resident Inspector Catawba Nuclear Station INPO Records Center 700 Galleria Place Atlanta, GA 30339-5957 Document Control Desk Page 3 December 20, 2012 bxc (electronic copy)(with attachment): INPO L.E. Harmon C.S. Kamilaris R.D. Hart G.Y. Helton S.F. Hatley (ICES) M.K. Green R.T. Simril, Jr. B.C. Carroll M.C. Nolan W.J. Pritchett, Jr. T.L. Patterson K.R. Alter H.D. Brewer R.E. Abbott, Jr. B.J. Horsley S.L. Western bxc (hard copy)(with attachment): D.B. Alexander L.S. Nichols L.J. Rudy ELL Master File CN-801.01 LER File RGC Date File NCMPA-1 NCEMC PMPA ICES Lee.Harmon@NRC.gov NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013
(10-2010) Estimated burden per response to comply with this mandatory collection request: 80 hours. Reported
lessons learned are incorporated into the licensing process and fed back to industry. Send commentsLICENSEE EVENT REPORT (LER) regarding burden estimate to the Records and FOIA/Privacy Service Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to infocollects.resource@nrclov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used(See reverse for required number of to impose an information collection does not display a currently valid OMB control number, the NRCdigits/characters for each block) may not conduct or sponsor, and a person is not required to respond to, the information collection. r1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE Catawba Nuclear Station, Unit 2 05000414 10OF •4. TITLE Diesel Generator (DG) 2B Was Unknowingly Inoperable from 09/28/12 to 10/23/12 Due to Failed Tachometer
Relay Power Supply | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.72(b)(3)(ii), Degraded or Unanalyzed Condition | 05000247/LER-2012-001 | Technical Specification (TS) Prohibited Condition Caused by an Inoperable 23 Emergency Diesel Generator Fuel Oil Storage Tank Due to Fuel Oil Below TS Limit | 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000269/LER-2012-001 | Unanalyzed Conditions Exist for Standby Shutdown Facility Mitizated Events | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000445/LER-2012-002 | COMANCHE PEAK 05000445 10OF06 | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident 10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System | 05000413/LER-2012-002 | Discovery of Inadequacy in Surveillance Testing of Solid State Protection System | 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000261/LER-2012-002 | Unplanned LCO 3.5.4 Entry Due to RWST alignment to Purification | 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 | 05000410/LER-2012-002 | Loss of Isolation Function on RHR Shutdown Cooling Suction Line due to Breaker Trip | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000482/LER-2012-002 | . One Train of Automatic Safety Infection Blocked During Entry Into Mode 3 Due To Procedural Weakness | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000361/LER-2012-002 | Emergency Diesel Generator Vibration Trip Not Bypassed For Non-Accident Condition | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition | 05000346/LER-2012-002 | Leak from Reactor Coolant Pump Seal Piping Socket Weld due to High Cycle Fatigue | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded | 05000333/LER-2012-002 | High Pressure Coolant Injection Pressure Control Valve Failure | 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 | 05000306/LER-2012-002 | Unit 2 Emergency Diesel Generators Inoperable Due To Missing Flood Control Barrier Seal | 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System | 05000250/LER-2012-002 | Non-compliance with TS 3.4.9.3 due to Manual Isolation Valve Found in Incorrect TS Configuration | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i) | 05000278/LER-2012-002 | Failure of Primary Containment Isolation Valve due to Foreign Material Results in Condition Prohibited by TS | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000316/LER-2012-002 | Unit 2 Reactor Trip from Generator Trip Due to Incorrect Relay Setting | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000282/LER-2012-002 | Unplanned Actuation of 121 Motor Driven Cooling Water Pump | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000298/LER-2012-002 | Improper Rotor Installation Causes Failure of Diesel Generator to Start | 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000247/LER-2012-002 | Technical Specification (TS) Prohibited Condition Caused by New Fuel Assemblies Stored in a Configuration Prohibited by the TS | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000237/LER-2012-002 | Inlet Steam Drain Pot Drain Line Leaks Result in HPCI Inoperabilities | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000298/LER-2012-003 | Reactor Building Doors Opened Simultaneously Causes Loss of Safety Function | 10 CFR 50.73(a)(2)(v), Loss of Safety Function | 05000410/LER-2012-003 | Suppression Pool Level Below Technical Specification Limit During Mode Change | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000261/LER-2012-003 | Plant Modification Interfered with the Operation of Containment Wide Range Level Indicator | | 05000298/LER-2012-004 | Cooper Nuclear Station 05000298 1 of 4 | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat | 05000410/LER-2012-004 | Manual Reactor Scram due to a Loss of Main Turbine Gland Sealing Steam Resulting in Lowering Condenser Vacuum | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000382/LER-2012-004 | Essential Chiller Oil Leak Creates Unanalyzed Past Operability Condition | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 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 | 05000265/LER-2012-004 | Drywell Radiation Monitor Failed Downscale | | 05000261/LER-2012-004 | Reactor Tripped Due to a Turbine Trip Caused by a Feedwater Isolation Signal from Steam Generator 'B' High Level | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000454/LER-2012-004 | Reactor Pressure Vessel Head Control Rod Drive Mechanism Penetration Nozzle Weld Repair Surface Indications | | 05000254/LER-2012-004 | Breech in Secondary Containment | | 05000482/LER-2012-004 | Two Charging Pumps Capable of Injecting into the RCS Due to Inadequate Definition of Centrifugal Charging Pump in LCO 3.4.12 | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000410/LER-2012-005 | Automatic Diesel Actuation Due to the Loss of a 115 kV Offsite Power Source | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000298/LER-2012-005 | Cooper Nuclear Station 05000298 1 of 4 | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000298/LER-2012-006 | Missing Vent Plug Results in Technical Specifications Prohibited Condition | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000220/LER-2012-007 | High Pressure Coolant Injection System Logic Actuation Following an Automatic Turbine Trip Signal Due to High Reactor Water Level | 10 CFR 50.73(a)(2)(iv)(A), System Actuation |
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