IR 05000352/2010005
| ML110250035 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 01/24/2011 |
| From: | Paul Krohn Reactor Projects Region 1 Branch 4 |
| To: | Pacilio M Exelon Nuclear, Exelon Generation Co |
| Krohn P | |
| References | |
| IR-10-005 | |
| Download: ML110250035 (31) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION I
475 ALLENDALE ROAD
, KING OF PRUSSIA. PA 19406-1415 January 24, 2OII
]
Mr. MichaelJ. Pacilio Senior Vice President, Exelon Generation Company, LLC President and Chief Nuclear Officer, Exelon Nuclear 4300 Winfield Rd, Warrenville, lL 60555 SUBJECT: LIMERICK GENERATING STATION - NRC INTEGMTED tNSPECTlON REPORT 05000352/201 0005 AND 05000353/201 0005
Dear Mr. Pacilio:
On December 31 ,2010, the U. S. Nuclear Regulatory Commission (NRC) completed an inspection at your Limerick Generating Station Units 1 and 2. The enclosed integrated inspection report documents the inspection results which were discussed on January 7 ,2011, with Mr. W. Maguire and other members of your staff.
The inspection examined activities conducted under your license as they relate to safety and compliance with the Commission's rules and regulations anp-observed with the conditions of your license.
The inspectors reviewed selected procedures and records, activities, and interviewed personnel based on the results of the inspection, no findings were identified.
f n accordance with 10 Code of Federal Regulations (CFR) Part2.390 of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of the NRC's document system (ADAMS). ADAMS is accessible from the NRC Website at http://www.nrc.qov/readins-rm/adams.html (the Public Electronic Reading Room).
Sincerely, P*-z I Z*4-Paul G. Krohn, Chief Projects Branch 4 Division of Reactor Projects Docket Nos: 50-352, 50-353 License Nos: NPF-39, NPF-85
Enclosure:
Inspection Report 05000352/201 0005 and 05000353/201 0005
SUBJECT:
LIMERICK GENERATING STATION - NRC INTEGRATED INSPECTTON REPORT 05000352/201 0005 AND 05000353/201 0005
Dear Mr. Pacilio:
On December 31 ,2010, the U. S. Nucfear Regufatory Commission (NRC) completed an inspection at your Limerick Generating Station Units 1 and 2. The enclosed integrated inspection report documents the inspection results which were discussed on January 7,2011, with Mr. W. Maguire and other members of your staff.
The inspection examined activities conducted under your license as they relate to safety and compliance with the Commission's rules and regulations and with the conditions of your license.
The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel based on the results of the inspection, no findings were identified.
In a
REGION I Docket Nos: 50-352,50-353 License Nos: NPF.39, NPF-85 Report No: 05000352/201 0005 and 05000353/201 0005 Licensee: Exelon Generation Company, LLC Facility: Limerick Generating Station, Units 1 & 2 Location: Sanatoga, PA 19464 Dates: October 1, 2010 through December 31, 2010 Inspectors: E. DiPaolo, Senior Resident Inspector N. Sieller, Resident Inspector J. Hawkins, Acting Resident Inspector A. Rosebrook, Senior Project Engineer T. Moslak, Health Physicist J.Caruso, Senior Operations Engineer (Section 1R11.2)
J. D'Antonio, Senior Operations Engineer (Section 1R1 1.2)
J. Tomlinson, Operations Engineer (Section 1R1 1.2)
C. Crisden, Emergency Preparedness Specialist Approved by: Paul G. Krohn, Chief Projects Branch 4 Division of Reactor Projects Enclosure
SUMMARY OF FINDINGS
lR 0500035212010005;05000353/2010005; 1010112010-1213112010; Limerick Generating
Station, Units 1 and2; routine integrated report.
The report covered a three-month period of inspection by resident inspectors, a senior project engineer, a health physicist, an emergency preparedness specialist, and an announced inspection by operations engineers. The NRC's program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, "Reactor Oversight," Revision 4, dated December 2006.
No findings were identified.
REPORT DETAILS
Summarv of Plant Status Unit 1 began the inspection period operating at full rated thermal power (RTP). On December 4, operators reduced power to approximately 94 percent to facilitate main turbine valve testing, control rod scram timg testing, a control rod pattern adjustment, and to perform segondary plant maintenance. Power was restored to full RTP on December 5. Unit 1 '
remained at full RTP for the remainder of the inspection period.
Unit 2 began the inspection period operating at full RTP. On October 23, power was reduced (unplanned) to approximately 50 percent as a result of the trip of the 'A' recirculation pump motor-generator set. Following troubleshooting and repairs to the generator voltage regulator, power was further reduced on October 24 to approximately 33 percent to facilitate the restart of the 'A' recirculation pump. Power was restored to full RTP on October 25. On October 30, operators reduced power to 85 percent to facilitate a follow up control rod pattern adjustment.
Power was restored to full RTP on October 31. A power reduction to 85 percent was performed on November 20 to facilitate a control rod pattern adjustment. Full power was restored on November 21. On December 3, power was reduced (unplanned) to approximately 58 percent as a result of the trip of the 'A' recirculation pump motor-generator set. Operators reduced power to approximately 35 percent to facilitate the restart of the 'A' recirculation pump following troubleshooting and repairs to the recirculation pump motor-generator set generator voltage regulator. Full RTP was restored on December 6. On December 18, operators reduced power to approximately 80 percent to facilitate main turbine valve testing, fuel channel distortion testing, and a control rod pattern adjuptment. The unit was restored to full RTP on I December 19. Unit 2 remained at full RTP for the remainder of the inspection period.
1. REACTORSAFETY
Cornerstones: Initiating Events, Mitigating Systems and Barrier Integrity
1R01 Svstem Seasonal Adverse Weather Protection (71111.01 - 1 seasonal sample)
a. Inspection Scope
The inspectors assessed the effectiveness of the licensee's cold weather protection program as it related to ensuring that equipment in the facility's spray pond pump house would remain functional and available in cold weather conditions. This equipment includes the emergency service water (ESW) pumps, residual heat removal (RHR)service water pumps, motor-operated valves associated with the spray pond, and support electrical equipment. ln addition to reviewing the licensee's program-related documents and procedures, walkdowns were conducted of the lreeze protection equipment (e.9., ventilation system dampers, building heating system, etc.) associated with the above systems/components. The inspectors observed plant conditions and evaluated those conditions against criteria documented in procedure GP-7, "Cold Weather Preparation and Operation." Licensee problem identification and resolution associated with cold weather protection was also assessed. Documents reviewed are listed in the Attachment.
c b.
Findinqs No findings were identified.
1R04 EquipmentAliqnment
Partial Walkdown (71111.04Q - 3 samples)
a. Inspection Scope
The inspectors performed partial walkdowns of the plant systems listed below to verify operability following realignment after a system outage window or while safety-related equipment in the opposite train was inoperable, undergoing surveillance testing (ST), or potentially degraded. The inspectors used Technical Specifications (TS), Exelon operating procedures, plant piping and instrumentation diagrams (P&lD), and the Updated Final Safety Analysis Report (UFSAR) as guidance for conducting partial system walkdowns. The inspectors reviewed the alignment of system valves and electrical breakers to ensure proper in-service or standby configurations as described in plant procedures and drawings. During the walkdowns, the inspectors evaluated the material condition and general housekeeping of the systems and adjacent spaces. The documents reviewed are listed in the Attachment. The inspectors performed walkdowns of the following areas:
r Emergency diesel generator (EDG) D23 on October 21,2Q10;
.
'A' control room emergency fresh air supply system following return-to-service on November 3,2010; and o Unit 2 high pressure coolant injection (HPCI) system when the 'B' loop of emergency service water was out-of-service (OOS) on December 2,201Q.
b. Findinqs No findings were identified.
1R05 Fire Protection
Fire Protection - Tours (71111.05Q - 4 samples)
a. Inspection Scope
The inspectors conducted a tour of the four areas listed below to assess the material condition and operational status of fire protection features. The inspectors verified that combustible materials and ignition sources were controlled in accordance with Exelon's procedures. Fire detection and suppression equipment was verified to be available for use, and passive fire barriers were verified to be maintained in good material condition.
The inspectors also verified that station personnel implemented compensatory measures for OOS, degraded, or inoperable fire protection equipment in accordance with the station's fire plan. The documents reviewed are listed in the Attachment. The inspectors toured the following areas:
.
Spray Pond Pumphouse, Western Half (Fire Area 122);
.
Spray Pond Pumphouse, Eastern Half (Fire Area 123)',
.
Control Room and Peripheral Rooms (Fire Area 24), and
.
Remote Shutdown Room (Fire Area 26).
b. Findinqs No findings were identified.
I
1R06 Flood Protecti6n Measures (71111.06 - 1 internal flooding sample)
a. Inspection ScoPe The inspectors reviewed the UFSAR and related flood analysis documents to identify areas that can be affected by internal flooding, to identify features designed to alert operators of a flooding event, and to identify features designed for coping with internal flooding. The inspectors performed a walkdown of the Main Control Room Chiller RoomJlneactor Enclosure, Elevation 200') and adjacent areas. The inspectors observed flood protection features to assess their ability to minimize the impact of a flooding event. The inspectors performed a review of operator actions contained in off-normal procedures for flooding to verify that the actions can reasonably be used to achieve the desired outcome. The documents reviewed are listed in the Attachment.
b. Findinqs No findings were identified.
t 1R1 1
.1 Resident Inspector Quarterlv Review (71111.11Q
- 1 sample)
a. Inspection Scope
On November g, 2010, the inspectors observed two annual licensed operator simulator examinations (LSE5-2004). The simulator scenarios tested the operators' ability to respond to operating equipment failures, reactivity transients, loss of drywell cooling, and loss of coolant leaks in the drywell. The inspectors observed licensed operator performance including operator critical tasks, which are required to ensure the safe operation of the react,or and protection of the nuclear fuel and primary containment barriers. The inspectors also assessed crew dynamics and supervisory oversight to verify the ability of operators to properly identify and implement appropriate TS actions, reguiatory reports, emergency event declarations, and notifications. The inspectors oOlerveO training instructor critiques and assessed whether appropriate feedback was provided to the licensed operators. The documents reviewed are listed in the
.
b. Findinqs No findings were identified.
.z Biennial Requalification Proqram Review (71111.118- 1 sample)
Insoection Scope The following inspection activities were performed using NUREG 1021, Revision 9, Supplement 1, "Operator Licensing Examination Standards for Power Reactors,"
lnspection Procedure Attachment71111 1 1, "Licensed Operator Requalification Program," Appendix A, "Checklist for Evaluating Facility Testing Material," and Appendix B, "Suggested Interview Topics."
A review was conducted of recent operating nistory documentation found in inspection reports, licensee event reports, the licensee's corrective action program, and the most recent, NRC plant issues matrix. The inspectors also reviewed specific events from the licensee's corrective action program which indicated possible training deficiencies to verify that they had been appropriately addressed. The senior resident inspector was also consulted for insights regarding licensed operators performance. These reviews did not detect any operational events that were indicative of possible training deficiencies.
For the 2010 examination cycle, the biennial written examinations (i.e., administered in 2OOg) and annual operating tests administered for weeks three, four, and five were reviewed for content, quality, and excessive overlap to ensure that these exams met the criteria established in the Examination Standards and 10 CFR 55.59' On December 10, 2010, the results of the annual operating tests for 2010 were reviewed to determine if pass/fail rates were consistent with the guidance of NUREG-1021, Revision 9, Supplement 1, "Operator Licensing Examination Standards for Power Reactors," and NRC Manual Chapter 0609, Appendix l, "Operator Requalification Human Performance Significance Determination Pilocess," were also performed. The review verified the following:
.
Crew pass rates were greater than 80 percent (Pass rate was 100 percent);
.
Individual pass rates on the written examination were greater than 80 percent (N/A -
Biennial written examination was not administered this yeal;
.
Individual pass rates on the job performance measures of the operating exam were greater than 80 percent (Pass rate was 98 percent); and o More than 75 percent of the individuals passed all portions of the operating examination (Pass rate was 98 percent).
Observations were made of the dynamic simulator examinations and job performance measures (JPMs) administered during the week of November 15, 2010, for Operations and Staff Crew C. These observations included facility evaluations of crew and individual performance during the dynamic simulator examinations and individual performance of JPMs.
The remediation plans for 22 out-of{he-box scenarios were reviewed to assess the effectiveness of the remedial training. Two reactivations were reviewed to ensure that 10 CFR 55.53 license conditions and applicable program requirements were met.
Instructors and training/operation's management were interviewed for feedback on their training program.
A sample of ten operator medical examinations were also reviewed for compliance with license conditions, including NRC regulations.
Simulator performance and fidelity were reviewed for conformance to the reference plant control room. Selected simulator deficiency reports were reviewed to assess licensee prioritization and timeliness of resolution. Simulator testing records were reviewed to verify that scheduled tests were performed.
b. Findinqs No findings were identified.
1R12 Maintenance Effectiveness (71111.12Q - 1 sample)
a. Inspection Scope
The inspectors evaluated Exelon's work practices and follow-up corrective actions for one issue within the scope of the maintenance rule. The inspectors reviewed the performance history of these structures, systems, and components (SSCs) and assessed the effectiveness of Exelon's corrective actions, including any extent-of-condition determinations to address potential common cause or generic implications.
The inspectors assessed Exelon's problem identification and resolution actions for these issues to evaluate whether Exelon had appropriately monitored, evaluated, and dispositioned the issues in accordance with Exelon procedures and the requirements of 1O CFR Part 50.65, "Requirements for Monitoring the Effectiveness of Maintenance." In addition, the inspectors reviewed the maintenance rule classifications, performance criteria, and goals for these SSCs and evaluated whether they appeared reasonable and appropriate. The documents reviewed are listed in the Attachment. The inspectors tI reviewed the following issue:
o lssue Report (lR) 1 137553 ESW pinhole leak repair - ESW loop 'B' return piping from Unit 2 RHR pump compartment unit cooler.
b. Findinqs No findings were identified.
1R13 Maintenance RiskAssessments and EmeroentWork Control
a. Inspection ScoPe The inspectors evaluated the effectiveness of Exelon's maintenance risk assessments required by 10 CFR Part 50.65(a)(4). This inspection included discussion with control room operitors and risk analysis personnel regarding the use of Exelon's on-line risk monitoring software. The inspectors reviewed equipment tracking documentation, daily work schedules, and per.formed plant tours to gain assurance that the actual plant configuration matched the assessed configuration. Additionally, the inspectors verified that Exelon's risk management actions, for both planned and emergent work, were consistent with those described in Exelon procedure, ER-M-600-1042, "On-Line Risk Management." The documents reviewed are listed in the Attachment. The inspectors reviewed the following samPles:
.
Units 1 and 2 on-line risk profile during the EDG D12load reject test with the 20 offsite power source unavailable on October 6' 2010; I
.
Unit 2 on-line risk profile while in single recirculation loop operations following 'A' motor generator (MG) trip October 22 - October 24,2010; o Unit 1 on-line risk and compensatory measures during fire header partial outage November 5 - November 8, 2010;
.
Units 1 and 2 on-line risk profile when the 'B' control enclosure chiller was discovered to be unavailable due to insufficient ESW flow on November 13, 201Q;
.
Units 1 and 2 on-line risk profile when the 222 Plant Services bus was de-energized November 24 - 25 due to a supply feeder cable fault; and
.
Unit 2 risk profile while in single recirculation loop operations following 'A' MG trip December 3.2010 - December 5, 2010.
b. Findinos No findings were identified.
1R15 Operabilitv Evaluations
a. lnsoection Scope The inspectors assessed the technical adequacy of a sample of seven operability evaluations to ensure that Exelon properly justified TS operability and verified that the subject component or system remained available such that no unrecognized increase in risk occurred. The inspectors reviewed the UFSAR to verify that the system or component remained available to perform its intended safety function. In addition, the inspectors reviewed compensatory measures implemented to ensure that the measures worked and were adequately controlled. The inspectors also reviewed a sample of lRs to verify that Exelon identified and corrected deficiencies associated with operability evaluations. The documents reviewed are listed in the Attachment. The inspectors reviewed the following evaluations:
.
lR 1120701, Radiation monitor failed check source functional test;
.
lR 1132289, Degraded wire connection on Unit 1 drywellfloor drain sump level monitor;
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lR 1137553, ESW pinhole leak on 'B' loop return piping from Unit 2 RHR pump compartment unit cooler (OPE-10-008, Revision 08);
.
lR 1143600, ESW'B' loop flow balance issues;
.
lR 1143434, Unit 1 scram discharge volume (SDV) valve exceeded maximum allowed stroke time;
.
lR 1151354, Unit 1 HPCI turbine mechanical overspeed will not reset; and
.
lR 1153065, EDG D14 fuel oil supply pressure fluxuations during operations.
b. Findinqs No findings were identified.
1R19 Post-Maintenance Testinq (71111.19 - I samples)
a. Inspection Scope
The inspectors reviewed eight post-maintenance tests to verify that procedures and test activities ensured system operability and functional capability. The inspectors reviewed Exelon's test procedures to verify that the procedures adequately tested the safety functions that may have been affected by the maintenance activity, and that the acceptance criteria in the procedures were consistent with information in the licensing and design basis documents. The inspectors also witnessed the test or reviewed test data to verify that the results adequately demonstrated restoration of [he affected safety functions. The documents reviewed are listed in the Attachment. The inspectors reviewed the following samPles:
.
R1 152057, Repair Unit 1 Division lV steam leak detection;
.
C0235528, Unit 2 'A' MG set voltage regulator dynamic testing after card replacements;
.
C0235261, Troubleshoot and rework Technical Support Center emergency ventilation system outside air damper;
.
C0231042, ESW'B'loop flow balance;
.
C0236019, Unit 2'A' recirculation pump MG repair;
.
41 786977 , Loss of power to Unit 2 outboard main steam isolation valve logic;
.
C0235392, Replace Unit 2 Division lll emergency core cooling system inverter; and
.
C0236065, Adjust pressure regulator to Unit 1 SDV piping vent primary containment isolation valve (XV-O47 -1F01 1).
b. Findinqs No findings wpre identified.
t
1R22 SurveillanceTestinq (71111.22-7 samples; 5routinesurveillances, 1in-service testing
(lST) and 1 reactor coolant system leakage)
a. Inspection Scope
The inspectors either witnessed the performance of, or reviewed test data, for seven STs associated with risk-significant SSCs. The reviews verified that Exelon personnel followed TS requirements and that acceptance criteria were appropriate. The inspectors also verified that the station established proper test conditions, as specified in the procedures, that no equipment preconditioning activities occurred, and that acceptance criteria were met. The documents reviewed are listed in the Attachment. The inspectors reviewed the following samPles:
.
5T-6-052-760, Safeguard Piping Fill Quarterly Valve Test;
.
5T-6-060-460-1, Primary Containment lsolation Capability Check;
.
5T-6-092-323-1, D13 DG Loss of Coolant Accident Load Reject Testing and Fast Start Operability Test Run;
.
5T-6-082-365-0, Inoperable Unit 1 Safeguard Power Supply Actions for Both Units;
.
3T-6-049-230-1, Reactor Core lsolation Cooling Pump, Valve & Flow IST;
.
5T-6-047-200-1, SDV Exercise Test; and
.
5T-6-107-596-2, Drywell Floor Drain Sump/ Equipment Drain Tank Surveillance Log/
OPCON 1, 2, 3 (reactor coolant system leakage).
b. Findinss No findings were identified.
Cornerstone: Emergency Preparedness (EP)
1EP2 Alert and Notification Svstem (ANS) Evaluation.(71114.02 - 1 sample)a.
An onsite review was conducted to assess the maintenance and testing of the current Limerick ANS. The inspectors reviewed ANS procedures and the updated Limerick ANS design report to ensure Exelon's compliance with design report commitments for system maintenance and testing. A sample of lRs pertaining to the ANS was reviewed for causes, trends, and corrective actions. The inspectors observed the conduct of the Limerick monthly siren test. During the inspection, the inspectors also interviewed the Mid-Atlantic EP Manager in regards to the new ANS which is planned for approval in April 201 1. The inspection was conducted in accordance with NRC Inspection Procedure 71114, Attachment 2. Planning Standard, 10 CFR 50.47(b)(5) and the related requirements of 10 CFR 50, Appendix E, were used as reference criteria.
b.
Findinss No findings were identified.
1EP3 Emeroencv Response Oroanization (ERO\ Staffilq and Auomentation Svstem
a. lnspection Scope The inspectors conducted a review of Limerick's ERO augmentation staffing requirements and the process for notifying and augmenting the ERO was conducted.
This was performed to ensure the readiness of key licensee staff to respond to an emergency event and to ensure Exelon's ability to activate their emergency facilities in a timely manner. The inspectors reviewed the Limerick and corporate ERO rosters, station and corporate augmentation reports since March 2009, and CRs related to the ERO staffing augmentation system. The inspectors also reviewed a sampling of ERO responder's training records to ensure training and qualifications were up to date. The inspection was conducted in accordance with NRC Inspection Procedure 71114,
10 CFR 50, Appendix E, were used as reference criteria.
b. Findinqs No findings were identified.
1EP4 Emerqencv Action Level (EAL) and Emerqencv Plan Chanoes
a. Inspection Scope
various since the last NRC inspection of this program area, Exelon implemented procedures- Exelon had changes to their Emergency Plan and implementing made to the Plan' determined that, in acdordance with 1O CFR 50.54(q), any change decrease in and its lower-tier implementing procedures' had not resulted in any standards in effectiveness of the Plan, and that the revised Plan continued to meet the reviewed all 50.47(b) and the requirements of 10 cFR 50, Appendix E. The inspectors to the security EALs as endorsed Emergency Action Level changeg, including changes plan changes including the chinges by Ndl gg-02, Revision S. A simple of emergency plan implementing procedures, were evaluated for any potential to lower-tier decreases in"r"if"n.y the effeJtiveness of the Emergency Plan. However, this review by and does not inspectors was not documented in an tttRc satety Evaluation Report Therefore, these changes remain constitute forr"irunC approval of the changes.
inspection was conducted in subject to future NRC inspection in their entirety. The accordance witn runc lnspection Procedure 71-114, Attachment 4' The requirements in 1O CFR 50.5a(q)were used as reference criteria' b. Findinqs No findings were identified.
1EPs Correction of Emerqencv Preparedness Weaknesses (71114'05 - 1 sample)a. lnsoection Scope and reports to The inspectors reviewed a samplipg of self-assessment procedures The inspebtors assess Exelon's ability to evaluate their EP performance "nd-ptogr"ms.
2010, initiated by reviewed a sampling or cnr from March 2009 through December reviewed.l0 CFR Exelon at Limerick fiom drills and audits. Additionally, the inspectors This inspection was so.s+1t) audits from 2009 and 2010; and self-assessment reports.
5' conducted in accordance with NRC lnspection Procedure 71114, requirements of 10 CFR 50' Planning Standard, tO Cfn 50.47(b)(14), and the related Appendix E, were used as reference criteria' h Findinqs No findings were identified'
RADIATION SAFETY
cornerstones: occupational and Public Radiation safety (71124'01- 1 sample)2RSO1 Radiolooical Hazard Assessment and Exposure controls a.
Inspection ScoPe the following During the period December 13 - 17,2010, the inspectors conducted and controlling activiies to verify that the licensee was evaluating, monitoring, locked high radiation areas, including the radiological hazards for work performed in other radiological controlled Independent Spent Fuel Storage Installation (lSFSl), and in these areas' areas. and workers were adheiing to these controls when working lmplementation of these controls was reviewed against the criteria contained in 10 CFR 20, TS's, and Exelon's procedures. The documents reviewed listed in the Attachment.
Radioloqical Hazards Assessment The inspectors reviewed recent revisions to radiation protection procedures regarding various radiation protection processes, including radiological postings, and contamination monitoring. The inspectors determined that the new revisions did not reduce the scope or effectiveness of previously established radiological controls.
Radioloqical Hazards Control and Work Coveraqe The inspectors toured accessible radiological controlled areas in Units 1 &2, including the lSFSl, turbine buildings, and reactor buildings to confirm the accuracy of survey data and the adequacy of postings and radiation work permits (RWP). The inspectors reviewed survey maps for areas toured to determine the timeliness of survey data and the adequacy of RWP controls.
Contamination and Radioactive Material Control The inspectors observed workers surveying and releasing potentially contaminated materials for unrestricted use. The inspectors verified that the counting instrumentation was located in a low background area and that the instruments sensitivity was appropriate for the type of contamination being measured.
Problem ldentification and Resolution Relevant lRs, associated with radiological controls, and electronic dosimeter dose/dose rate alarm reports initiated between March through November 2010, were reviewed by the inspectors. The inspectors discussed the lRs with licensee staff to determine if the follow up activities were being conducted in an effective and timely manner, commensurate with their safety significance.
b. Findinos No findings were identified.
OTHER ACTIVITIES
4OA1 Performance lndicator (Pl) Verification
.1 Barrier lnteoritv and Mitioatinq Svstems Cornerstone Pls
a. Inspection Scope
The inspectors sampled Exelon's submittal of the Barrier lntegrity cornerstone and Mitigating Systems cornerstone Pls listed below to verify the accuracy of the data recorded from October 2009 though September 2010. The inspectors utilized performance indicator definitions and guidance contained in Nuclear Energy Institute (NEl) 99-02, "Regulatory Assessment Performance Indicator Guidelines," Revision 6, to verify the basis in reporting for each data element. The inspectors reviewed various documents, including portions of the main control room logs, issue reports, power history curves, work orders, and system derivation reports. The inspectors also discussed the method for compiling and reporting performance indicators with cognizant engineering personnel and compared graphical representations from the most recent Pl report to the raw data to verify that the report correctly reflected the data. The documents reviewed are listed in the Attachment.
Cornerst6ne: Barrier lnteoritv
.
Units 1 and 2 Reactor Coolant System Leak Rate (8102); and o Units 1 and 2 Reactor Coolant System Activity (8101).
Cornerstone: Mitiqating Svstems
o Units 1 and 2 Mitigating System Performance Index, Cooling Water Systems (MS10).
b Findinqs No findings of significance were identified.
occupational Exposure control Effectiveness Pl (71151- 1 sample)lnspection Scope The inspeqtors reviewed implementation of the licensee's Occupational Exposure Control Effbctiveness Pl Program (ORO1). Specifically, the inspectors reviewed electronic dosimetry alarm repofts, lRs, and associated documents, for occurrences involving locked high radiation areas, very high radiation areas, and unplanned exposures against the criteria specified in NEI 99-02, "Regulatory Assessment performance Indicator Guideline, Revision 6," to verify that all occurrences that met the NEI criteria were identified and reported as performance indicators.
b. Findinqs No findings were identified.
.J RETS/ODCM Radioloqical Effluent occurrences Pl (71151- 1 sample)
a. Inspection Scope
The inspectors reviewed relevant effluent release issue reports for the period October 2009 thiough Novemb er, 2010, for issues related to the public radiation safety performanCe indicator, which measures radiological effluent release occurrences that exceed 1.5 mrem/qtr whole body or 5.0 mrem/qtr organ dose for liquid effluents; Smrads/qtr gamma air dose, 10 mrad/qtr beta air dose, and 7.5 mrads/qtr for organ dose for gaseoujeffluents. The inspectors reviewed the following documents to ensure the licensee met all requirements of the performance indicator (PRQ1):
.
Monthly projected dose assessment results due to radioactive liquid and gaseous effluent releases;
.
Quarterly projected dose assessment results due to radioactive liquid and gaseous effluent releases: and
.
Dose assessment procedures.
b.
Findinos No findings were identified.
]
.4 Emerqencv Preparedness Cornerstone Pls
a. Inspection Scope
The inspectors reviewed data for Limerick's EP Pls, which are:
- (1) Drill and Exercise Performance (DEP) (EP01);
- (2) ERO Drill Participation (EP02); and,
- (3) ANS Reliability (EP03). The inspectors reviewed the Pl data and its supporting documentation from the fourth quarter of 2009 through the third quarter of 2010 to verify the accuracy of the reported data. The review of these Pls was conducted in accordance with NRC Inspection Procedure 71151, using the acceptance criteria documented in NEI 99-02, "Regulatory Assessment Performance lndicator Guidelines," Revision 6.
b.
Findinqs No findings were identified.
4c.42 ldentification and Resolution of Problems t
.1 Review of ltems Entered into the Corrective Action Proqram (CAP)
a.
lnspection Scope As required by Inspection ProcedureTll52, "ldentification and Resolution of Problems,"
and in order to help identify repetitive equipment failures or specific human performance issues for follow-up, the inspectors screened all items entered into Limerick's CAP. The inspectors accomplished this by reviewing each new condition report, attending management review committee meetings, and accessing Exelon's computerized database.
b.
Findinqs No findings were identified.
.2 Semi-Annual Review to ldentifv Trends (71152 - 1 trend sample)
a. Inspection Scope
The inspectors performed a semi-annual review of site issues, to identify trends that might indicate the existence of more safety significant safety issues, as required by f nspection Procedure 71152, "ldentification and Resolution of Problems." The inspectors included in this review, repetitive or closely-related issues that may have been documented by Exelon outside of the corrective action program, such as Plant Health Committee reports including the Top Ten Equipment lssues List, the Plant Health Committee lssues List, the Open Action ltems List, and the Performance lmprovement Integration Matrix. The inspectors also reviewed Exelon's corrective action database for the third and fourth quarters of 2010, to assess lRs written in various subject areas (e.9.,
equipment problems, human performance issues, etc.), as well as individual issues identified during the NRC's daily lR review (Section 4042.1).
Findinqs and Observations ]
No findings were identified. The inspectors assessed that Exelon was identifying issues at a low threshold and entering the issues into the CAP for resolution.
Notwithstanding, the inspectors noted a recent negative trend concerning the health of non-safety-related underground 13kV power supply cables. Within a 7-month period, Limerick experienced three non-safety related cable failures. ln two of the three cases, the cables had previously been identified by Exelon as requiring repair or replacement due to degraded insulation that was discovered during testing. Specifically:
.
On April 2, 2010, the 122 Plant Services Transformer supply cable faulted shortly after being placed in service following maintenance (lR 1051496). Part of the maintenance had been to repair a known, degraded section of cable insulation.
However, the fault occurred in a section of cable that had not been repaired, despite being previously identified as degraded. At the time, Unit 1 was in a refueling outage and therefore the effect on the plant was minimal.
.
On June 23, 2010, operators insefted a manual scram on Unit 1 as a result of the loss of both recirculation pumps (lR 1083732). The initiator for the transient wastthe fault of an underground portion of the 13kV power supply cable to the 144D Technical Support Center Transformer. This, coupled with other non-related equipment failures, resulted in the loss of the operating stator cooling water pump and the tripping of the recirculation motor-generator sets. For more detail see FIN 05000352/2010004-02, "Failure to ldentify lncorrectly Adjusted Control Power Relay Resulting in Unit 1 Manual Scram." This cable had not been tested, but had been identified as requiring testing in the future.
.
On November 24,201Q, the 222 Plant Services Transformer supply cable faulted, causing the loss of two of the three Unit 2 service water pumps (lR 1144472). This cable was known to have degraded insulation resistance but had not been repaired.
Due to the ambient temperatures at the time of the loss (i.e. service water temperatures were cool), Unit 2 was able to maintain full power operations using the remaining service water pumP.
The inspectors reviewed the extent of power supply cable insulation degradation at Limerick. The inspectors noted that there were two other 13kV power supply cables that testing had identified as degraded and requiring action in the near term. These cables were issociated with the Unit 1 'A' circulating water pump and the Unit 1 'C'circulating water pump. Because of the recent failures, Exelon identified the need to expedite replacement of known degraded cables and testing of the remaining cables. As a result, a high impact team was established to coordinate cable replacements and other corrective actions. At the close of the inspection period, cable replacements were planned to commence in January 2011. ln addition, Exelon planned to coordinate with an industry research group to help determine the causes of cable failures and failure mechanisms. The inspectors concluded that Exelon had identified this trend and Exelon's actions taken or planned to address the trend appeared to be comprehensive.
The inspectors determined this trend was not applicable to safety-related cables because test results for the safety-related 4kV underground cables indicated they had acceptable insulation resistance. This was primarily due to more favorable operating conditions (e.9., lower operating voltage and intermittent operation of the load).
.3 Annual Sample: Underqround Cable VaultWater Intrusion (71152 - 1 Annual sample)
a. lnspection Scope The inspectors reviewed Limerick's actions under lR 1056715, which was initiated to track Exelon fleet-wide actions to improve long-term health of medium and low voltage power cables routed in underground structures, The inspectors reviewed the corrective actions taken or planned to assure the timeliness was commensurate with the potential safety significance. The inspectors also interviewed plant personnel regarding the identified issues and implemented corrective actions. Specific documents reviewed are listed in the Attachment.
b. Findinos and Observations No findings were identified.
lR 1003826 was initiated by Limerick to track project actions necessary to establish and maintain the underground manholes and conduits of both safety-related and non-safety-related electrical manholes in a dry condition. As discussed in Section 4042.2 above, the inspectors noted a recent negative trend concerning the health of non-safety-related underground 13kV power supply cables. For all three non-safety-related power supply cable failures experienced at Limerick in 2010, Exelon suspected that the wet underground environment contributed to the failure. As a result, Exelon identified the need to expedite replacement of known degraded cables and testing of cables that had not been previously tested.
Exelon's long{erm action plan to improve underground cable reliability was still under development at lhe time of this inspection. The long-term plan will be customized based on the results of manhole inspections, water infiltration rates, and the risk ranking of cables. The inspectors concluded, from review of the draft plan and discussions with engineers, that the long-term plan will address appropriate factors including cable testing, cable replacements, underground drainage system repairs and/ or modifications, etc. For safety-related manholes and conduits, Exelon planned to install a pumping system to maintain them dry. At the time of this inspection, the modification was scheduled for installation by June 1 ,2011. Based on a review of the key actions in lR 1056715 and lR 1003826 that have been taken to date, the inspectors concluded that Exelon's planned actions appeared to be timely and would improve long-term health of the cables.
4OA3 Event Follow-up
a. Inspection Scope
For the three plant events listed below, the inspectors reviewed and/or observed plant parameters, reviewed personnel performance, and evaluated performance of mitigating systems. The inspectors communicated the plant events to appropriate regional personnel and compared the event details with criteria contained in Inspection Manual Chapter 0309, "Reactive Inspection Decision Basis for Reactors," for consideration of potential reactive inspection activities. As applicable, the inspectors verified that Exelon made appropriate emergency action classification assessments and properly reported the event in accordance with 10 CFR Parts 50.72 and 50.73. The inspectors reviewed Exelon's follow-up actions related to the events to assure that appropriate corrective actions were implemented commensurate with their safety significancq,
.
Unit 2 'A' recirculation pump trip on October 23,2010',
.
Loss of Plant Services Bus 222 on November 24,2010; and o Unit 2 'A' recirculation pump trip on December 3,2010.
b.
Findinqs No findings were identified.
4OA5 Other Activities
.1 Independent Spent Fuel Storaqe Installation (lSFSl) Monitorinq Controls
(71124.01160855 - 1 sample)
a. Inspection Scope
The inspectors reviewed routine operations and monitoring of the ISFSI (Docket No.
72-1004)., The inspectors walked down the ISFSI and with the assistan of a Senior Radiation'Protection Technician, performed independent dose rate measurements of the storage modules, and confirmed module temperatures were within the required limits.
The inspectors also reviewed plant equipment operator logs for ISFSI surveillances, relevant issue reports, and environmental ISFSI dosimetry records. Radiological control activities for the ISFSI were evaluated against 10 CFR 20, ISFSI TS's, and the licensee's procedures.
The inspectors also reviewed the effectiveness of radiological controls for the most recent loading and transfer of five
- (5) dry storage casks, that was conducted during the June through August 2010 period. Actual worker dose was compared to forecasted estimated exposure and determined be within a reasonable range (< 50% difference)and cumulative exposure was less than 5 person-rem.
b. Findinqs No findings were identified.
.2 (Closed) Unresolved ltem (URl) 05000352/353/2009006-02, Technical Specification
Requirements for Motor-Operated Valve (MOV) Thermal Overload Bvpass Feature
a. Inspection Scope
During the 2009 component design bases inspection (CDBI), a URI was opened to determine if Exelon was meeting the intent of TS 3.8.4.2.b regarding the bypassing of thermal overloads on certain manually operated MOVs during an accident condition.
Exelon entered the issue into the CAP. The inspectors reviewed the lR and corrective 1q actions initiated to address the URl, which included a technical evaluation of the issue.
The inspectors reviewed procedures OP-LG-108-101-1004, "Valves," Revision 4, and OP-LG*103-102-1002, "Strategies for Successful Transient Mitigation," Revision 5, to determine whether the operators were provided adequate guidance on manually operated MOV operation and bypassing of the thermal overloads. The inspectors interviewed training staff to ensure thermal overload bypass operation was part of the long range training program, and that the appropriate training had been in place and conducted prior to the CDBI. The inspectors also interviewed operators and observed simulated operator actions in the simulator to assess operator knowledge on proper valve stroke indication, thermal overload actuation indication, and thermal overload bypass operation of the manually operated MOVs to ensure complete valve operation.
b. Findinss No performance deficiencies or findings were identified and the URI is closed.
4OAO Meetinqs. lncludinq Exit On January 7, the inspectors presented the inspection results to Mr. W. Maguire and other members his staff. The inspectors confirmed that proprietary information was not included in the inspection report.
ATTACHMENT: SUPPLEMENTAL I NFORMATION
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
- W. Maguire, Site Vice President
- E. Callan, Plant Manager !
- S. Johnson, Assistant Plant Manager
- R. Dickinson, Director of Training
- P. Gardner, Director of Operations
- R. Kreider, Director of Maintenance
- C. Gerdes, Security Manager
- D. Merchant, Radiation Protection Manager
- D. Palena, Manager Nuclear Oversight
- J. Hunter, Manager, Regulatory Assurance
- S. Bobyock, Manager, Plant Engineering Programs
- N. Dennin, Shift Operations Superintendent
- R. McLaughlin, Operations Support Manager
- W. Lewis, Senior Engineering Manager
- M. Gillin, Balance of Plant Engineering Manager
- K. Slough, Mechanical/Structural Engineering Design Manager
- M. DiRado, Engineering Rapid Response Manager
- J. Risteter, Radiation Protection Manager
- R. Harding, Regulatory Assurance Engineer
- C. Goff, Operations Training Manager t
- T. Carr, Maintenance Supervisor
R. Rhode - Licensed Operator Requalification Training Supervisor
- V. Hydro, Simulator Supervisor
- R. Forst, Annual Operating Exam Developer
- S. Cohen, Annual Operating Exam Developer
- J. Mihm, Biannual Written DeveloPer
- F. Buzynski, Systems Engineer
Barth, Systems Engineer
Brittain, Senior Staff Engineer
Deihm, Work Week Manager
Leahy, Procurement Engineer Supervisor
Minicozzi, System Engineer
Tracey, Systems Engineer
Weiss, Systems Engineer
Welch, Maintenance Planner QV Inspector
Zaharchuk, Systems Engineer
Commiskey, Radiological Engineer
Wahl, Environmental Scientist
NRC Personnel
- E. DiPaolo, Senior Resident Inspector
- N. Sieller, Resident Inspector
- J. Hawkins, Acting Resident Inspector
- A. Rosebrook, Senior Project Engineer
- C. Crisden, Emergency Preparedness Specialist
A-Z
LIST OF ITEMS
OPENED OR CLOSED
Opened
None
Closed
- 05000352/353/2009006-02 URI Technical Specification Requirements for Motor Operated Valve Thermal Overload Bypass Feature (Section 4C45.2)
Opened and Closec None
Discussed
None