11-24-2010 | On October 1, 2010, with Unit 3 in -Mode 6 and Unit 4 in Mode 1 operating at 100% power, an HHSI pump discharge valves creating a flow path from the Unit 4 Refueling Water Storage Tank ( RWST) through the HHSI pumps to the Unit 3 cold leg injection lines, which were open to the refueling cavity. The Unit 4 HHSI system was at a reduced capability rendering it inoperable from approximately 09:51 until 10:27 (36-minutes) when the HHSI isolation valve 3-867 was closed. The event was discovered at approximately 10:05. An 8-hour report ( EN# 46303) was made to the NRC Operations Center in accordance with 10 CFR 50.72(b)(3)(v)(D). The causes of the event include: 1) no administrative control of the operating unit Safety Injection flowpath with one unit shutdown, and 2) poor organizational processes resulted in failure to recognize the requirements to maintain Emergency Core Cooling System ( ECCS) flowpath integrity, during periods when the opposite unit is in a low pressure condition. Corrective actions include revision of processes and procedures that control ECCS flowpath integrity during periods when the opposite unit is in a low pressure condition. |
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DESCRIPTION OF THE EVENT
On October 1, 2010, with Unit 3 in Mode 6 and Unit 4 in Mode 1 operating at 100% power, an unplanned entry into Technical Specification 3.0.3 occurred at approximately 09:51 due to a misalignment of the Unit Refueling Water Storage Tank (RWST) through the HHSI pumps to the Unit 3 cold leg injection lines, which were open to the refueling cavity. The event allowed the gravity drain of 1426 gallons of borated water from the Unit 4 RWST to the Unit 3 refueling cavity via the Unit 3 reactor coolant system (RCS) [AB] cold leg injection lines. Under these conditions, the Unit 4 HHSI System was inoperable for was in Mode 6 and the HHSI System was not required to be operable to support Unit 3. The event was discovered at approximately 10:05.
At 17:56, an 8-hour report (EN# 46303) was made to the NRC Operations Center in accordance with 10 CFR 50.72(b)(3)(v)(D) for a condition that could have prevented the fulfillment of a safety function of a system required to mitigate the consequences of an accident. This event was entered into the Corrective Action Program as AR 584026584026
ANALYSIS OF THE EVENT
The primary purpose of the HHSI System is to automatically deliver cooling water to the reactor core in the event of a loss-of-cooling accident (LOCA). The HHSI pumps automatically start and develop sufficient head and flow to inject borated water to the RCS during the injection and recirculation phases of a LOCA.
This action replaces lost reactor coolant and supports short and long term emergency core cooling during reactor decay heat generation. The Turkey Point HHSI System design is a shared system with cross-connect capability and provides for all four HHSI pumps to be able to inject coolant into either Unit 3 or Unit 4.
The HHSI pumps and their associated power supplies are shared between Units 3 and 4. With one unit operating and one unit in an outage, plant Technical Specifications require three operable HHSI pumps (two from the operating unit and one from the outage unit), with each pump capable of being powered from its associated operable emergency diesel generator, and with the discharge of each pump aligned to the operating unit's RCS cold leg. During refueling outages, the outage unit's HHSI pump is aligned to take suction from the operating unit's RWST. This ensures a viable suction source is maintained for all three required HHSI pumps while the water volume in the outage unit's RWST is used for flooding-up the refueling cavity to support refueling activities.
On October 1, 2010, while hanging an Equipment Clearance Order (ECO) for valve and breaker work in the Unit 3 Safety Injection (SI) system, the two Unit 3 HHSI pump discharge Motor Operated Valves (MOVs) to the Unit 3 RCS cold legs (MOV-3-843A & MOV-3-843B - HHSI Cold Leg Injection) were manually opened prior to closing the manual isolation valve (3-867 - SI Boundary Isolation Valve) [BQ, ISV] in the discharge flow path to the Unit 3 cold legs. The action to close the manual isolation valve was a subsequent step in the ECO. The inadvertent failure to maintain the HHSI pump discharge to the Unit 3 RCS cold legs isolated created a flow path from the Unit 4 RWST through the HHSI pumps to the Unit 3 cold leg injection lines, which were essentially open to the refueling cavity. At approximately 10:05 hours on 10/01/2010, the Reactor Controls Operator noticed that the water level in the Unit 4 RWST was decreasing. Upon further investigation, it was determined that the RWST level had started decreasing at approximately 09:51 hours.
Immediate action was taken by the operating crew, and manual isolation valve 3-867 was closed at 10:27 hours, isolating the flowpath. The event allowed the gravity drain of 1426 gallons of borated water from the Unit 4 RWST to the Unit 3 refueling cavity via the Unit 3 RCS cold leg injection lines.
Following the inadvertent transfer of Unit 4 RWST inventory, it was not immediately recognized that the misalignment of the Unit 3 HHSI pump discharge valves could also have adversely affected Unit 4 which was operating in Mode 1 at 100% power. Specifically, the misalignment of the Unit 3 HHSI pump discharge valves affected the safety function of the HHSI pumps to automatically start on an SI signal and develop sufficient head and flow to inject borated water to the Unit 4 RCS for emergency core cooling. Had and 4 RCS cold leg injection lines would have been cross-connected and the majority of flow would have been directed to the outage unit refueling cavity, vice the operating unit RCS cold legs. Consequently, the safety function of the HHSI pumps to provide adequate water inventory to the Unit 4 RCS cold leg injection lines in the event of a LOCA was challenged during the time period that the Unit 3 HHSI pump discharge valves were open. This event rendered the HHSI System inoperable for Unit 4.
This potential Technical Specification impact on Unit 4, the operating unit, was identified by site management at approximately 16:00 hours on 10/01/2010 during further discussions of the details of the event. Based on these discussions, it was determined that the operating unit (Unit 4) had an unplanned entry into a 1-hour shutdown action statement of Technical Specification 3.03 for the period from the time of discovery of the RWST decreasing water level (09:51 hours) to the time the draindown event was terminated (10:27 hours), a period of 36 minutes. Since the HHSI System was inoperable during this period, this resulted in a required 8-Hour Notification Report to the NRC pursuant to 10 CFR 50.72(b)(3)(v)(D) for a condition that could have prevented the fulfillment of a safety function of a system required to mitigate the consequences of an accident.
CAUSE OF THE EVENT
The event was evaluated to determine the root cause and contributing causal factors. There were two root causes identified for the event:
1. Inadequate administrative control of the operating unit Safety Injection flowpath with one unit shutdown (and Safety Injection operability not required on shutdown unit).
2. Poor organizational processes led to a reliance on knowledge only and resulted in failure to recognize the requirements to maintain Emergency Core Cooling System (ECCS) flowpath integrity, through proper isolations during periods when the opposite unit is in a low pressure condition.
REPORTAB ILITY
Turkey Point Unit 3 was in Mode 6 and Unit 4 was operating at 100% power in Mode 1. For single unit operation, Technical Specification 3.5.2, "ECCS Subsytems — Tavg Greater than or Equal to 350 °F," requires three operable HHSI pumps (two associated with the operating unit and one from the opposite unit), each capable of being powered from its associated operable diesel generator, with discharge aligned to the RCS cold leg. The misalignment of the Unit 3 HHSI pump discharge valves created a flow path from the Unit 4 RWST through the HHSI pumps to the Unit 3 cold leg injection lines, which were open to the refueling cavity. Under these conditions, the Unit 4 HHSI System was inoperable since it would not have RCS and refueling cavity via the open flow path.
10 CFR 50.73(a)(2)(v) requires reporting of:
Any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to:
(A) Shut down the reactor and maintain it in a safe shutdown condition; (B) Remove residual heat; (C) Control the release of radioactive material; or (D) Mitigate the consequences of an accident.
Since the HHSI System safety function was prevented for the 36-minute period, the event is reportable in accordance with 10 CFR 50.73(a)(2)(v)(B) and (D) since the HHSI System functions to both remove residual heat and mitigate the consequences of an accident were affected.
10 CFR 50.73(a)(2)(vii) requires reporting of:
Any event where a single cause or condition caused at least one independent train or channel to become inoperable in multiple systems or two independent trains or channels to become inoperable in a single system designed to:
(A) Shut down the reactor and maintain it in a safe shutdown condition; (B) Remove residual heat; (C) Control the release of radioactive material; or (D) Mitigate the consequences of an accident.
While the HHSI System trains are not totally independent due to various piping cross-connections and common suction and discharge lines, the pumps are intended to be independent both electrically and mechanically so that a single failure of a pump can be tolerated. The HHSI System safety function of automatically delivering cooling water to Unit 4 was prevented for the 36-minute period due to the misalignment of the Unit 3 HHSI pump discharge valves creating a flow path from the Unit 4 RWST through the HI-ISI pumps to the Unit 3 cold leg injection lines. The event is reportable in accordance with 10 CFR 50.73(a)(2)(vii)(B) and (D) since the HHSI System functions to both remove residual heat and mitigate the consequences of an accident were affected.
ANALYSIS OF SAFETY SIGNIFICANCE
FPL performed a calculation to quantify and document the change in Core Damage Frequency (ACDF), change in Large Early Release Frequency (ALERF), the Incremental Conditional Core Damage Probability (ICCDP), and the Incremental Conditional Large Early Release Probability (ICLERP) associated with a 36 minute period where HHSI was rendered unavailable for Unit 4.
The ICCDP and ICLERP were calculated from the results of four case studies using the Turkey Point Probabilistic Safety Assessment (PSA) model. The results are shown in the following two Tables, respectively.
Unit 4 ICCDP Description Result Baseline CDF (per year) 1.80E-06 CDF (HHSI out of service) (per year) 2.96E-03 ACDF (per year) 2.96E-03 HHSI outage duration (minutes) 36 ICCDP 2.0E-07 The resulting ICCDP value of 2.0E-07 falls well below the 1.0E-06 Green-to-White ICCDP threshold for the Significance Determination Process (SDP) specified in NRC Inspection Manual Chapter (IMC) 0609, "Significance Determination Process." Moreover, as indicated in NRC Regulatory Guide (RG) 1.177, "An Approach for Plant-Specific, Risk-Informed Decision-Making: Technical Specifications," an ICCDP of less than 5.0E-07 is considered small and would be considered acceptable by the NRC for a change to a Technical Specification allowed outage time (AOT).
Unit 4 ICLERP Description Result Baseline LERF (per year) 1.56E-07 LERF (HHSI out of service) (per year) 3.76E-06 ALERF (HHSI out of service) 3.6E-06 HHSI outage duration (minutes) 36 ICLERP 2.5E-10 The resulting ICLERP value of 2.5E-10 falls well below the 1.0E-07 Green-to-White ICLERP threshold for the SDP specified in NRC IMC 0609. As indicated in RG 1.177, an ICLERP of less than 5.0E-08 is considered small and would be considered acceptable by the NRC for a change to a Technical Specification AOT.
Additionally, to approximate the effect of external events, the ACDF and ALERF were doubled, resulting in an ICCDP of 4.0E-07 and an ICLERP of 5.0E-10. Accordingly, these results still remain as a Green risk indicator per the SDP guidelines.
In summary, the risk associated with the unavailability of the HHSI System for the 36-minute period, results in the analysis finding of a Green risk indicator per the calculated ICCDP and ICLERP, as applied to the SDP guidelines based predominantly on the short duration.
CORRECTIVE ACTIONS
There were two corrective actions identified:
1. Utilize the Equipment Clearance Order (ECO) to control HHSI flowpath integrity (use of already in place cold shutdown placards, dual purpose to prevent Pressurized Thermal Shock and loss of HHSI discharge flowpath integrity). Use the electronic database eSOMS to track the position of cold shutdown placards (caution tags remain electronically hanging).
2. Revise procedure 3/4-0SP-202.1, "Safety Injection/Residual Heat Removal Flowpath Verification," Attachment 1 for the opposite unit to address the alignment requirements of the outage unit MOV- 3/4-843A/B valves to maintain the integrity of the HHSI discharge flowpath for the operating unit.
3. Update procedure 3/4-GOP-305, "Hot Standby To Cold Shutdown," to include information discussing why restrictions to the operation of valves are required. Update operator logs to include 12-hour readings to verify the alignment requirements of the outage unit MOV-3/4-843A/B valves to maintain the integrity of the HHSI discharge flowpath for the operating unit.
Corrective actions to address the event's contributing factors have been entered in the Turkey Point Corrective Action Program in AR 584026584026
ADDITIONAL INFORMATION
component function identifier (if appropriate)].
Condition Report AR 584026584026was initiated due to this event.
FAILED COMPONENTS IDENTIFIED: None PREVIOUS SIMILAR EVENTS: None
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05000220/LER-2010-001 | Reactor Scram Due to Inadequate Post Maintenance Testing | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000410/LER-2010-001 | Reactor Scram Due to Inadvertent Actuation of the Redundant Reactivity Control System During Maintenance | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000395/LER-2010-001 | Reactor Building Cooling Units Reduced Air Flow Rate Below Technical Specification Limits | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000382/LER-2010-001 | Spent Fuel Pool Cooling Single Failure | 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.72(b)(3)(ii), Degraded or Unanalyzed Condition | 05000374/LER-2010-001 | High Pressure Core Spray System Declared Inoperable Due to Failed Room Ventilation Control Relay | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000373/LER-2010-001 | Unauthorized Individual Gained Access to the Protected Area. | | 05000370/LER-2010-001 | Loose connection in a panel board serving a Solid State Protection System Train concurrent with redundant train maintenance could have prevented fulfillment of a safety function. | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - 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Mitigate the Consequences of an Accident 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000498/LER-2010-001 | Unit Shutdown Required by Technical Specifications | 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown | 05000316/LER-2010-001 | Valid Actuation of Auxiliary Feedwater System in Response to Valid Steam Generator Low-Low Levels | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000321/LER-2010-001 | Corrosion Induced Bonding Results in Safety Relief Valve Lift Setpoint Drift | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000336/LER-2010-001 | Millstone Power Station Unit 2 Reactor Trip | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000413/LER-2010-001 | Technical Specification Violation Associated with Failure to Perform Offsite Circuit Verification | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000440/LER-2010-001 | Invalid Isolation Signal Results in Shutdown Cooling Interruption | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat | 05000424/LER-2010-001 | Breaker Failure Results in I B Train Containment Cooling System Being Declared Inoperable | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000416/LER-2010-001 | Automatic Reactor Scram On Decreasing Reactor Water Level Due To Inadvertent Reactor Feed Pump Trip | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000249/LER-2010-001 | OPRM Power Supply Failure during Maintenance Results in Unit 3 Automatic Reactor Scram | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000251/LER-2010-001 | Two Shutdown Bank Rods Were Dropped from Fully Withdrawn Position | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(iv), System Actuation | 05000261/LER-2010-002 | Plant Trip due to Electrical Fault | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000255/LER-2010-002 | Condition that Could Have Prevented the Fulfillment of a Safety Function | 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 | 05000335/LER-2010-002 | Opened ECCS Boundary Door in Violation of Identified Compensatory Measures | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000334/LER-2010-002 | 270 Degree Circumferential Flaw Found on Residual Heat Removal System Drain Valve Socket Weld | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000316/LER-2010-002 | Containment Divider Barrier Seal Mounting Bolts Not Properly Installed | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000250/LER-2010-002 | Fuel Transfer Pump Failure Renders 3B Emergency Diesel Generator Inoperable | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000269/LER-2010-002 | Manual Reactor Trip due to 1A1 and 1A2 Reactor Coolant PumDHigh Vibration Indication | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000315/LER-2010-002 | Manual Auxiliary Feedwater Actuation in Response to Main Feedpump Failure | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000271/LER-2010-002 | Inoperability of Main Steam Safety Relief Valves due to Degraded Thread Seals | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000277/LER-2010-002 | Improperly Fastened Rod Hanger Results in Inoperable Subsystem of Emergency Service Water | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000413/LER-2010-002 | Discovery of Reactor Coolant System Pressure Boundary Leak at Thermowell 1NCTW5850 Seal Weld. | | 05000282/LER-2010-002 | Postulated Flooding of Unit 1 Fuel Oil Transfer Pump Motor Starters Could Have Resulted In Reduced Fuel Oil Inventory | | 05000414/LER-2010-002 | Duke Energy Corporation Catawba Nuclear Station 4800 Concord Road York, SC 29745 803-701-4251 803-701-3221 fax December 15, 2010 U.S. Nuclear Regulatory Commission
Attention: Document Control Desk
Washington, D.C. 20555
Subject:�Duke Energy Carolinas, LLC (Duke Energy)
Catawba Nuclear Station, Unit 2
Docket No. 50-414
Licensee Event Report 414/2010-002
Pursuant to 10 CFR 50.73(a)(1) and (d), attached is Licensee Event Report 414/2010-002, Revision 0 entitled, "Technical Specification Violation Involving Mode Change with Inoperable Auxiliary Feedwater System Train Due to Closed Pump Discharge Valves". This report is being submitted in accordance with 10 CFR 50.73(a)(2)(i)(B). 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. Sincerely, faius4- A James R. Morris LJR/s Attachment www.duke-energy.corn (14 Document Control Desk Page 2 December 15, 2010 xc (with attachment): L.A. Reyes 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, Ill NRC Senior Resident Inspector Catawba Nuclear Station INPO Records Center 700 Galleria Place Atlanta, GA 30339-5957 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 infocollectssesource@nre.gov, 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 info(mation collection. 1.. FACILITY NAME 2. DOCKET NUMBER I3. PAGE Catawba Nuclear Station, Unit 2 05000414 1 OF 7 4. TITLE Technical Specification Violation Involving Mode Change with Inoperable Auxiliary Feedwater System Train Due to Closed Pump Discharge ValvesD • | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000306/LER-2010-002 | Unit 2 Turbine Shutdown Due To the Loss of a Main Feed Water Pump That Resulted in a Reactor Scram | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000440/LER-2010-002 | Piping Leak Results in Condition Prohibited by Technical Specifications | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000382/LER-2010-002 | Main Feedwater Isolation Valve B exceeded allowed outage time due to tubing connection failure | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000370/LER-2010-002 | ref Energy® REGIS T. REPKO Vice President McGuire Nuclear Station Duke Energy MGO1VP / 12700 Hagers Ferry Rd. Huntersville, NC 28078 980-875-4111 980-875-4809 fax regis.repko(Codu ke-energy.corn 10 CFR 50.73 May 10, 2011 U.S. Nuclear Regulatory Commission ATTENTION: Document Control Desk Washington, D.C. 20555 Subject: D Duke Energy Carolinas, LLC McGuire Nuclear Station, Unit 2 Docket Nos. 50-370 Licensee Event Report (LER) 370/2010-02, Supplement 1 Problem Investigation Process (PIP) M-10-05982 Pursuant to 10 CFR 50.73 Sections (a) (1) and (d), attached is Supplement 1 to Licensee Event Report 370/2010-02, regarding past inoperability of the Unit 2 "A" Train Nuclear Service Water System and satisfies the commitment to supplement the LER following completion of the root cause analysis This supplement to LER 370/2010-02 supersedes the LER previously submitted December 20, 2010. Completion of the root cause analysis has not affected the original reporting criteria which was completed 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 needed to remove residual heat. Additionally, the supplement did not affect the significance of the event which was considered to be of no significance with respect to the health and safety of the public. There are no regulatory commitments contained in this report. If questions arise regarding this LER, contact Rick Abbott at 980-875-4685. Very truly yours, Zi1:77 Regis T. Repko Attachment www. duke-energy. corn U.S. Nuclear Regulatory Commission May 10, 2011 Page 2 cc:�V. M. McCree, Regional Administrator U.S. Nuclear Regulatory Commission, Region II
Marquis One Tower
245 Peachtree Center Ave., NC, Suite 1200
Atlanta, Georgia 30303-1257
Jon H. Thompson (Addressee Only)
Senior Project Manager (McGuire)
U.S. Nuclear Regulatory Commission
11555 Rockville Pike
Rockville, MD 20852-2738
J. B. Brady
Senior Resident Inspector
U.S. Nuclear Regulatory Commission
McGuire Nuclear Station
W. L. Cox Ill, Section Chief North Carolina Department of Environment and Natural Resources Division of Environmental Health Radiation Protection Section 1645 Mail Service Center Raleigh, NC 27699-1645 NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB. NO 3150-0104 EXPIRES: 08/31/2013 (10-2010) Estimated burden per response to comply with this mandatory collection request: SO hours. Reported 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 info (See reverse for required number of collects resmirceOnrc.gov, and to the Desk Officer, Office of Information and Regulatory digits/characters for each block) Affairs, NEOB-10202, (3150-01041, Office of Management and Budget, Washington, DC 20503. If a means used to impose an information 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, the information collection. LICENSEE EVENT REPORT (LER) 1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE McGuire Nuclear Station,2Unit 2 05000-212
0370 OF-7 4. TITLE Unit 2 Nuclear Service Water System "A" Train Past Inoperable due to
Failed Strainer Differential Pressure Instrument. | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 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-2010-002 | | | 05000456/LER-2010-002 | Limiting Condition for Operation Action Not Completed Within the Required Time | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000249/LER-2010-003 | Steam Leak Results in HPCI Inoperability | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000251/LER-2010-003 | Damaged Speed Sensor Caused the 4A Emergency Diesel Generator to be Inoperable | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
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