IR 05000289/2013003
| ML13211A022 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 07/30/2013 |
| From: | Hunegs G NRC/RGN-I/DRP/PB6 |
| To: | Pacilio M Exelon Nuclear Generation Corp, Exelon Nuclear |
| HUNEGS, GK | |
| References | |
| IR-13-003 | |
| Download: ML13211A022 (30) | |
Text
July 30, 2013
SUBJECT:
THREE MILE ISLAND STATION, UNIT 1 - NRC INTEGRATED INSPECTION REPORT 5000289/2013003
Dear Mr. Pacilio:
June 30, 2013
SUBJECT:
THREE MILE ISLAND STATION, UNIT 1 - NRC INTEGRATED INSPECTION REPORT 5000289/2013003
Dear Mr. Pacilio:
On June 30, 2013, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Three Mile Island, Unit 1 (TMI) facility. The enclosed inspection report documents the inspection results, which were discussed on July 19, 2013 with Mr. Rick Libra, Site Vice President, and other members of your staff.
The inspection examined activities conducted under your license as they relate to safety and compliance with the Commissions 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 this inspection, no findings were identified.
In accordance with 10 CFR 2.390 of the NRCs 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 NRCs document system (ADAMS). ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,
/RA/
Gordon K. Hunegs, Chief Reactor Projects Branch 6 Division of Reactor Projects
Docket Nos.: 50-289 License Nos.: DPR-50
Enclosure:
Inspection Report 05000289/2013003
w/Attachment: Supplemental Information
REGION I==
Docket No:
50-289
License No:
Report No:
Licensee:
Exelon Generation Company
Facility:
Three Mile Island Station, Unit 1
Location:
Middletown, PA 17057
Dates:
April 01 through June 30, 2013
Inspectors:
D. Werkheiser, Senior Resident Inspector
J. Heinly, Resident Inspector
S. Galbreath, Reactor Inspector
T. Moslak, Health Physicist
Approved by:
G. Hunegs, Chief
Projects Branch 6
Division of Reactor Projects (DRP)
Enclosure
SUMMARY
IR 05000289/2013003, 04/01/2013-06/30/2013; Three Mile Island, Unit 1, Integrated Inspection
Report.
This report covered a three-month period of inspection by resident inspectors and announced inspections performed by regional inspectors. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 4.
No findings were identified.
REPORT DETAILS
Summary of Plant Status
Unit 1 began the inspection period at 100 percent power. On May 25, 2013, operators reduced power to 89 percent to perform turbine valve testing. Operators returned the unit to 100 percent on May 26, 2013. The unit remained at or near 100 percent power for the remainder of the inspection period.
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
1R01 Adverse Weather Protection
.1 Readiness for Seasonal Extreme Weather Conditions
a. Inspection Scope
The inspectors performed a review of Exelons readiness for the onset of seasonal high temperatures. The review focused on the control building ventilation system and its ability to maintain control building temperatures within FSAR limits. The inspectors reviewed the Updated Final Safety Analysis Report (UFSAR), technical specifications, control room logs, and the corrective action program to determine what temperatures or other seasonal weather could challenge the system, and to ensure Exelon personnel had adequately prepared for these challenges. The inspectors reviewed station procedures, including Exelons seasonal weather preparation procedure and applicable operating procedures. The inspectors performed walkdowns of the selected system to ensure station personnel identified issues that could challenge the operability of the systems during. Documents reviewed for each section of this inspection report are listed in the Attachment.
b. Findings
No findings were identified.
.2 Summer Readiness of Offsite and Alternate Alternating Current (AC) Power Systems
a. Inspection Scope
The inspectors performed a review of plant features and procedures for the operation and continued availability of the offsite and alternate AC power system to evaluate readiness of the systems prior to seasonal high grid loading. The inspectors reviewed Exelons procedures affecting these areas and the communications protocols between the transmission system operator and Exelon. This review focused on changes to the established program and material condition of the offsite and alternate AC power equipment. The inspectors assessed whether Exelon established and implemented appropriate procedures and protocols to monitor and maintain availability and reliability of both the offsite AC power system and the onsite alternate AC power system. The inspectors evaluated the material condition of the associated equipment by interviewing the responsible system manager, reviewing issue reports and open work orders, and walking down portions of the offsite and AC power systems including the 500 kilovolt (KV) and 220 KV switchyards.
b. Findings
No findings were identified.
==1R04 Equipment Alignment
Partial System Walkdowns (71111.04 - 3 samples)
a. Inspection Scope
==
The inspectors performed partial walkdowns of the following systems:
A emergency feedwater system and turbine-driven sub-system during B motor-driven emergency feedwater valve maintenance on May 14, 2013
A reactor river water system during maintenance on B reactor river water valve RR-V-10B on June 12, 2013
A emergency safeguards actuation system relays and components during B channel testing after a planned relay replacement on June 19, 2013
The inspectors selected these systems based on their risk-significance relative to the reactor safety cornerstones at the time they were inspected. The inspectors reviewed applicable operating procedures, system diagrams, the UFSAR, technical specifications, work orders, condition reports, and the impact of ongoing work activities on redundant trains of equipment in order to identify conditions that could have impacted system performance of their intended safety functions. The inspectors also performed field walkdowns of accessible portions of the systems to verify system components and support equipment were aligned correctly and were operable. The inspectors examined the material condition of the components and observed operating parameters of equipment to verify that there were no deficiencies. The inspectors also reviewed whether Exelon staff had properly identified equipment issues and entered them into the corrective action program for resolution with the appropriate significance characterization.
b. Findings
No findings were identified.
==1R05 Fire Protection
==
.1 Resident Inspector Quarterly Walkdowns
a. Inspection Scope
The inspectors conducted tours of the areas listed below to assess the material condition and operational status of fire protection features. The inspectors verified that Exelon controlled combustible materials and ignition sources in accordance with administrative procedures. The inspectors verified that fire protection and suppression equipment was available for use as specified in the area pre-fire plan, and passive fire barriers were maintained in good material condition. The inspectors also verified that station personnel implemented compensatory measures for out of service, degraded, or inoperable fire protection equipment, as applicable, in accordance with procedures.
Control building A train ventilation component (AH-E-95A) fire protection lagging on April 5, 2013
Intake screen and pump house fire zone 2 [ISPH-FZ-2], on April 18, 2013
Auxiliary building, elevation 331 foot, chemical addition room [AB-FZ-10], on June 13, 2013
Fuel handling spent fuel pool floor, elevation 348 foot [FH-FZ-4], on June 18, 2013
b. Findings
No findings were identified.
.2 Fire Protection - Drill Observation
a. Inspection Scope
The inspectors observed station response to an actual small fire in a trash can at the waste handling packaging facility on April 4, 2013, which involved station fire brigade response. The fire was quickly extinguished by local personnel and resulted in no damage or injuries. Also, the inspectors observed a fire brigade drill scenario conducted on April 10, 2013 that simulated a fire in the A station battery room on the 322 elevation of the Control Building. The inspectors evaluated the readiness and actions of the plant fire brigade to fight fires. The inspectors verified that Exelon personnel identified deficiencies; openly discussed them in a self-critical manner at the post-drill/event debrief, and took appropriate corrective actions as required. The inspectors evaluated specific attributes as follows:
Proper wearing of turnout gear and self-contained breathing apparatus
Proper use and layout of fire hoses
Employment of appropriate fire-fighting techniques
Sufficient fire-fighting equipment brought to the scene
Effectiveness of command and control
Search for victims and propagation of the fire into other plant areas
Smoke removal operations
Utilization of pre-planned strategies
Adherence to the pre-planned drill scenario
Drill objectives met
The inspectors also evaluated the fire brigades actions to determine whether these actions were in accordance with Exelons fire-fighting strategies.
b. Findings
No findings were identified.
1R06 Flood Protection Measures
Review of Cables Located in Underground Bunkers/Manholes
a. Inspection Scope
The inspectors conducted an inspection of underground bunkers/manholes subject to flooding that contain cables whose failure could affect risk-significant equipment. The inspectors performed walkdowns of risk-significant areas, including cable vault E-4E and E-4W containing power cables scoped in the license renewal program, to verify that the cables were not submerged in water, that cables and/or splices appeared intact, and to observe the condition of cable support structures. The inspectors reviewed the passive water mitigation features designed to prevent water intrusion into the cable vaults were intact and effectively performing their function. The inspectors also ensured that drainage was provided and functioning properly in areas where dewatering devices were not installed.
b. Findings
No findings were identified.
1R11 Licensed Operator Requalification Program
.1 Quarterly Review of Licensed Operator Requalification Testing and Training
a. Inspection Scope
The inspectors observed licensed operator simulator training on June 24 and 28, 2013, which included the use of severe accident mitigating guidelines, walkthrough of up-coming control system relay replacements and how it would affect plant operations, and a review of NUREG-1022, Event Reporting Guidelines, Revision 3 changes. The inspectors evaluated operator performance during the simulated event and verified completion of risk significant operator actions, including the use of abnormal and emergency operating procedures. The inspectors assessed the clarity and effectiveness of communications, implementation of actions in response to alarms and degrading plant conditions, and the oversight and direction provided by the control room supervisor. The inspectors verified the accuracy and timeliness of the emergency classification made by the shift manager and the technical specification action statements entered by the shift technical advisor. Additionally, the inspectors assessed the ability of the crew and training staff to identify and document crew performance problems.
b. Findings
No findings were identified.
.2 Quarterly Review of Licensed Operator Performance in the Main Control Room
a. Inspection Scope
The inspectors observed control room operations during instrumentation and control surveillance testing conducted on June 25 and 26, 2013. The inspectors observed licensed operators performance to verify that procedure use, crew communications, and coordination of activities between work groups met the criteria specified in Exelons OP-AA-1, Conduct of Operations, Revision 0. In addition, the inspectors verified that licensee supervision and management were adequately engaged in plant operations oversight and appropriately assessed control room operator performance and similarly met established expectations and standards.
b. Findings
No findings were identified.
1R12 Maintenance Effectiveness
a. Inspection Scope
The inspectors reviewed the samples listed below to assess the effectiveness of maintenance activities on SSC performance and reliability. The inspectors reviewed system health reports, corrective action program documents, maintenance work orders, maintenance rule periodic assessment report and maintenance rule basis documents to ensure that Exelon was identifying and properly evaluating performance problems within the scope of the maintenance rule. For each sample selected, the inspectors verified that the SSC was properly scoped into the maintenance rule in accordance with 10 CFR 50.65 and verified that the (a)(2) performance criteria established by Exelon staff was reasonable. As applicable, for SSCs classified as (a)(1), the inspectors assessed the adequacy of goals and corrective actions to return these SSCs to (a)(2). Additionally, the inspectors ensured that Exelon staff was identifying and addressing common cause failures that occurred within and across maintenance rule system boundaries.
B emergency diesel generator criteria exceeded as documented in IR 1498010, on April 8, 2013
Maintenance Rule Periodic Assessment Topical Report for January 2011 to December 2012, on April 14, 2013
Loose parts monitor alarm maintenance preventable functional failure evaluation, on May 10, 2013
b. Findings
No findings were identified.
1R13 Maintenance Risk Assessments and Emergent Work Control
a. Inspection Scope
The inspectors reviewed station evaluation and management of plant risk for the maintenance and emergent work activities listed below to verify that Exelon performed the appropriate risk assessments prior to removing equipment for work. The inspectors selected these activities based on potential risk significance relative to the reactor safety cornerstones. As applicable for each activity, the inspectors verified that Exelon personnel performed risk assessments as required by 10 CFR 50.65(a)(4) and that the assessments were accurate and complete. When Exelon performed emergent work, the inspectors verified that operations personnel promptly assessed and managed plant risk.
The inspectors reviewed the scope of maintenance work and discussed the results of the assessment with the stations probabilistic risk analyst to verify plant conditions were consistent with the risk assessment. The inspectors also reviewed the technical specification requirements and inspected portions of redundant safety systems, when applicable, to verify risk analysis assumptions were valid and applicable requirements were met.
Station risk regarding Foxboro power supplies affected by issues documented in 10 CFR 21 notice EN 48863 and documented in IR 1496437, on April 2 - 15, 2013
Station risk during B emergency diesel generator work and diving operations to desilt river intake area #2 affecting safety-related river water pumps, on April 22 - 23, 2013
Station risk during diving operations to desilt river intake areas #4 and #5 affecting safety-related river water pumps, on May 2 - 3, 2013
Station risk during B emergency diesel generator work and maintenance on emergency feedwater valve EF-V-30D, on May 14, 2013
Station risk evaluation of emergency diesel generator surveillance testing with an impending severe thunderstorm warning, on June 13, 2013
b. Findings
No findings were identified.
1R15 Operability Determinations and Functionality Assessments
a. Inspection Scope
The inspectors reviewed operability determinations for the following degraded or non-conforming conditions:
Station blackout diesel generator (EG-Y-4) control room voltage indication lower than local indication as documented in IR 1503158, on April 17, 2013
Reinstallation of original speed switch for B emergency diesel generator, on April 24, 2013
Make-up pump discharge pressure transmitter (MU2-PT) out of tolerance as documented in IR 1507280, on May 1, 2013
B emergency diesel generator fuel leak at injector #9 documented in IR 1513793, May 14-15, 2013
Intake and pump screen house safety-related pump ventilation issues as documented in IR 1512260, May 10, 2013
B control building normal ventilation fan (AH-E-17B) delayed stop as documented in IR 1512953, on May 12, 2013
B control building emergency ventilation fan (AH-E-18B) trip as documented in IR 1515220, on May 20, 2013
The inspectors selected these issues based on the risk significance of the associated components and systems. The inspectors evaluated the technical adequacy of the operability determinations to assess whether technical specification operability was properly justified and the subject component or system remained available such that no unrecognized increase in risk occurred. The inspectors compared the operability and design criteria in the appropriate sections of the technical specifications and UFSAR to Exelons evaluations to determine whether the components or systems were operable.
Where compensatory measures were required to maintain operability, the inspectors determined whether the measures in place would function as intended and were properly controlled by Exelon. The inspectors determined, where appropriate, compliance with bounding limitations associated with the evaluations.
b. Findings
No findings were identified.
1R18 Plant Modifications
a. Inspection Scope
The inspectors reviewed the temporary modifications listed below to determine whether the modifications affected the safety functions of systems that are important to safety.
The inspectors reviewed 10 CFR 50.59 documentation and post-modification testing results, and conducted field walkdowns of the modifications to verify that the temporary modifications did not degrade the design bases, licensing bases, and performance capability of the affected systems.
TC-0151517 - ESAS J-C Relay Replacement, on June 13, 2013
b. Findings
No findings were identified.
1R19 Post-Maintenance Testing
a. Inspection Scope
The inspectors reviewed the post-maintenance tests for the maintenance activities listed below to verify that procedures and test activities ensured system operability and functional capability. The inspectors reviewed the test procedure to verify that the procedure adequately tested the safety functions that may have been affected by the maintenance activity, that the acceptance criteria in the procedure was consistent with the information in the applicable licensing basis and/or design basis documents, and that the procedure had been properly reviewed and approved. The inspectors also witnessed the test or reviewed test data to verify that the test results adequately demonstrated restoration of the affected safety functions.
A control building ventilation damper replacements on April 5, 2013
Replacement of circuit breaker (EG-H-2B-BK) under A1730435 that supports B emergency diesel generator (EDG), on April 25, 2013
B EDG post maintenance-outage under WOs R2184442 and R2206257, on April 26, 2013
B EDG speed switch repairs under WO C2012150-04, on April 24, 2013 Station blackout diesel generator control room voltage meter replacement under WO R2215121, on May 10, 2013
Air intake tunnel deluge sump pump (SD-P-7) after motor bearing greasing, on May 14, 2013
B control building normal ventilation fan (AH-E-17B) after damper solenoid replacement under A2329938, on May 15, 2013
b. Findings
No findings were identified.
1R20 Refueling and Other Outage Activities
a. Inspection Scope
The inspectors observed performance of the calibration and surveillance test of spent fuel pool area refueling bridge limit switches and fuel-assembly transfer system in May and June 2013.
b. Findings
No findings were identified.
1R22 Surveillance Testing
a. Inspection Scope
The inspectors observed performance of surveillance tests and/or reviewed test data of selected risk-significant SSCs to assess whether test results satisfied technical specifications, the UFSAR, and Exelon procedure requirements. The inspectors verified that test acceptance criteria were clear, tests demonstrated operational readiness and were consistent with design documentation, test instrumentation had current calibrations and the range and accuracy for the application, tests were performed as written, and applicable test prerequisites were satisfied. Upon test completion, the inspectors considered whether the test results supported that equipment was capable of performing the required safety functions. The inspectors reviewed the following surveillance tests:
CY-AA-170-1000, Meteorological Tower Instrumentation Test on April 11, 2013
1450-013, 4160/480 Volt Transformer Overcurrent Relay Test on April 13, 2013
1303-4.2A RPS Channel A CRD Breaker and Test Module Testing on April 22, 2013
ST-1303-4.16, Monthly Test of the B EDG, on April 26, 2013
ST-OP-TM-212-02, In-service test of A decay heat pump (DH-P-1A), on May 6, 2013 (in-service test)
ST-1303-4.16, Annual Voltage/Frequency Checks for A EDG, on May 9, 2013
OP-TM-220-251, RCS Leak Rate Determination, June 24, 2013 (leak rate)
b. Findings
No findings were identified.
Cornerstone: Emergency Preparedness
1EP6 Drill Evaluation
a. Inspection Scope
The inspectors evaluated the conduct of emergency event identification, classification, and notification during an evaluated hostile-action based emergency preparedness drill conducted on April 16, 2013. Exelon planned for this evolution to be evaluated and included in performance indicator data regarding drill and exercise performance. The inspectors also attended the post-evolution critique for the scenario. The focus of the inspectors activities was to note any weaknesses and deficiencies in the crews performance and ensure that Exelons evaluators noted the same issues and entered them into the corrective action program.
b. Findings
No findings were identified.
RADIATION SAFETY
Cornerstone: Public Radiation Safety
2RS6 Radioactive Gaseous and Liquid Effluent Treatment
a. Inspection Scope
Groundwater Protection Initiative (GPI) Program
During the period April 15 - 19, 2013, the inspector reviewed groundwater monitoring results and changes to Exelons program for identifying, mitigating, and monitoring contaminated spills/leaks to on-site groundwater pathways. The inspector used the guidance contained in Nuclear Energy Institute (NEI) 07-07, Industry Ground Water Protection Initiative (GPI), to evaluate the licensees implementation of the GPI.
Walkdowns and Observations The inspector reviewed the recent results of water samples taken from the monitoring well MS-22, located near the Unit 1 borated water storage tank (BWST), where elevated tritium concentrations were detected in April 2012. The inspector reviewed Exelons measures to identify the source and control the spread of contamination by installing additional monitoring well clusters in the vicinity of MS-22.
The inspector assessed the current on-site ground water sample results to determine the trends in the concentrations of tritiated water in the monitoring wells, determine the adequacy of the sampling program, and evaluate the suitability for the locations of new monitoring wells.
Problem Identification and Resolution The inspector assessed whether problems associated with the GPI program are being identified by the licensee at an appropriate threshold and are properly addressed for resolution in the Exelons corrective action program.
b. Findings and Observations
No findings were identified.
2RS7 Radiological Environmental Monitoring Program
a. Inspection Scope
During the period April 15 - 19, 2013, the inspector verified that the radiological environmental monitoring program (REMP) quantifies the impact of radioactive effluent releases to the environment and sufficiently validates the integrity of the radioactive gaseous and liquid effluent release program.
The inspector used the requirements in 10 CFR Part 20; 10 CFR Part 50 Appendix A Criterion 60 - Control of Release of Radioactivity to the Environment; 10 CFR 50 Appendix I Numerical Guides for Design Objectives and Limiting Conditions for Operations to Meet the Criterion As Low as is Reasonably Achievable (ALARA) for Radioactive Material in Light-Water-Cooled Nuclear Power Reactor Effluents; 40 CFR Part 190 Environmental Radiation Protection Standards for Nuclear Power Operations; 40 CFR Part 141 Maximum Contaminant Levels for Radionuclides; the guidance in RGs 1.23 Meteorological Measurements Program for Nuclear Power Plants, RG 4.1 Radiological Environmental Monitoring Programs for Nuclear Power Plants; RG 4.15 Quality Assurance for Radiological Monitoring Programs; NUREG 1301 Offsite Dose Calculation Manual (ODCM) Guidance: Standard Radiological Effluent Controls; applicable industry standards; and licensee procedures as criteria for determining compliance.
The inspector reviewed the Three Mile Island Annual Radiological Environmental Operating Reports for 2010 and 2011, and the results of licensee assessments since the last inspection to verify that the REMP was implemented and reported in accordance with requirements. This review included changes to the ODCM with respect to environmental monitoring, commitments in terms of sampling locations, monitoring and measurement frequencies, land use census, inter-laboratory comparison program, and analysis of data.
The inspector reviewed the Three Mile Island ODCM to identify locations of environmental monitoring stations. The inspector reviewed the Three Mile Island UFSAR for information regarding the environmental monitoring program and meteorological monitoring instrumentation. The inspector reviewed quality assurance audits and technical evaluations performed on the vendors analytical laboratory program. The inspector reviewed the Three Mile Island Annual Radioactive Effluent Release Reports and the most recent results from waste stream analysis, to determine if Exelon is sampling and analyzing for the predominant radionuclides likely to be released in effluents.
Site/Environmental Inspection The inspector walked down seven air sampling stations (Nos. E1-2, F1-3, G2-1, M2-1, A3-1, H3-1, Q15-1)) and eleven optically stimulated luminescent dosimeter (OSLD)monitoring locations (Nos. J1-1, F1-1, C1-1, L1-1, K1-1, J1-3, H3-1, E1-2, A3-1, Q15-1, M2-1) to determine whether they are located as described in the ODCM and to determine the equipment material condition.
For the selected air samplers, the inspector reviewed the calibration and maintenance records to verify the operability of the samplers components.
The inspector observed the collection and preparation of six environmental water samples. Included in these observations were three surface water samples (monitoring locations: J1-2, A3-2, Q9-1) and three drinking water samples (monitoring locations: Q9-1, G15-2, G15-3), The inspector determined whether the environmental sampling was representative of the release pathways as specified in the ODCM and that sampling techniques were performed in accordance with procedures.
The inspector toured milk sampling locations (E2-2, F4-1, G2-1, P4-1) to verify that the locations were as described in the ODCM. The inspector performed an assessment of whether Exelon has initiated sampling of other appropriate media upon loss of a required sampling station; e.g., establishing vegetation sampling to replace the loss of milk sampling.
Based on direct observation and review of records, the inspector assessed whether the meteorological instruments were operable, calibrated, and maintained in accordance with procedures. The inspector determined whether the meteorological data readout and recording instruments in the control room and at the meteorological tower were operable and were reading similar values. The inspector confirmed that redundant instrumentation was available and that the recovery rate for meteorological data was greater than 90%.
The inspector evaluated whether missed and/or anomalous environmental samples were identified and reported in the Annual Radiological Environmental Operating Reports.
The inspector selected events that involved a missed sample, inoperable air sampler, lost TLDs/OSLDs, or anomalous measurement to verify that Exelon has identified the cause and has implemented appropriate corrective actions.
The inspector assessed whether the controls associated with the Unit 1 condensate storage tanks, sodium thiosulfate tank, borated water storage tank, sodium hydroxide tank, radwaste piping, turbine building sump, and auxiliary building sump included operational and engineering measures to identify credible pathways for radioactive material to reach ground water. The inspector assessed whether Exelon has implemented a monitoring program to provide early detection of leakage from these components and has implemented mitigation measures to limit the migration of tritiated groundwater.
The inspector reviewed the decommissioning files, per 10 CFR 50.75 (g), to verify that any spills or leaks of contaminated material, were documented and monitored.
The inspector reviewed any significant changes made by Exelon to the ODCM as the result of changes to the land census, long-term meteorological conditions or modifications to the sampler stations since the last inspection. The inspector reviewed technical justifications for any changed sampling locations to verify that Exelon performed the reviews required to ensure that the changes did not affect its ability to monitor the impacts of radioactive effluent releases on the environment.
The inspector assessed whether the detection sensitivities for environmental samples met the lower limits of detection specified in the ODCM. The inspector reviewed the results of the Exelon inter-laboratory and intra-laboratory comparison programs to verify the adequacy of environmental sample analyses performed by the licensee. The inspector assessed whether the results included the radionuclide mix appropriate for the facility.
Identification and Resolution of Problems The inspector assessed whether problems associated with the REMP are being identified by Exelon at an appropriate threshold and appropriate corrective actions are assigned for resolution in the licensees corrective action program.
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA1 Performance Indicator Verification
.1 Reactor Coolant System (RCS) Specific Activity and RCS Leak Rate (2 samples)
a. Inspection Scope
The inspectors reviewed Exelons submittal for the RCS specific activity and RCS leak rate performance indicators for TMI for the period of April 1, 2012 through April 1, 2013.
To determine the accuracy of the performance indicator data reported during those periods, the inspectors used definitions and guidance contained in NEI Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 6. The inspectors also reviewed RCS sample analysis and control room logs of daily measurements of RCS leakage, and compared that information to the data reported by the performance indicator. Additionally, the inspectors observed surveillance activities that determined the RCS identified leakage rate, and chemistry personnel taking and analyzing an RCS sample.
b. Inspection Findings
No findings were identified.
4OA2 Problem Identification and Resolution
.1 Routine Review of Problem Identification and Resolution Activities
a. Inspection Scope
As required by Inspection Procedure 71152, Problem Identification and Resolution, the inspectors routinely reviewed issues during baseline inspection activities and plant status reviews to verify that Exelon entered issues into the corrective action program at an appropriate threshold, gave adequate attention to timely corrective actions, and identified and addressed adverse trends. In order to assist with the identification of repetitive equipment failures and specific human performance issues for follow-up, the inspectors performed a daily screening of items entered into the corrective action program and periodically attended issue report screening meetings.
b. Findings
No findings were identified.
.2 Semi-Annual Trend Review
a. Inspection Scope
The inspectors performed a semi-annual review of site issues, as required by Inspection Procedure 71152, Problem Identification and Resolution, to identify trends that might indicate the existence of more significant safety issues. In this review, the inspectors included repetitive or closely-related issues that may have been documented by Exelon outside of the corrective action program, such as trend reports, performance indicators, major equipment problem lists, system health reports, maintenance rule assessments, and maintenance or corrective action program backlogs. The inspectors also reviewed Exelons corrective action program database for the first and second quarters of 2013 to assess issue reports written in various subject areas (equipment problems, human performance issues, etc.), as well as individual issues identified during the NRCs daily condition report review (Section 4OA2.1). The inspectors reviewed the available Exelon quarterly trend reports for 2013 to verify that Exelon personnel were appropriately evaluating and trending adverse conditions in accordance with applicable procedures.
b. Findings and Observations
No findings were identified.
The inspectors evaluated a sample of various department issues that were provided as input into the quarterly trend report and rolled-up and identified as monitored trends.
This review included a sample of issues and events that occurred over the course of the past two quarters to objectively determine whether issues were appropriately considered or ruled as emerging or adverse trends, and in some cases, verified the appropriate disposition of resolved trends. The inspectors verified that these issues were addressed within the scope of the corrective action program. For example, the inspectors noted that consistent with an identified adverse trend in transient combustible-free zone violations and other fire protection issues into the 1st quarter 2013, a common-cause and root cause evaluation was completed by Exelon and corrective actions implemented in the 2nd quarter 2013. The inspectors noted a significant improvement in the implementation of fire protection requirements with no adverse trend noted by the end of the 2nd quarter 2013. Regarding the only other root cause, involving flood protection barriers, issues continue to be identified by the inspectors, however the issues were not safety-significant nor contributed to an adverse trend.
In other cases, Exelon has identified an adverse trend in the use of the corrective action program and took corrective actions, specifically with the staff and corrective action coordinators by reinforcing CAP standards and procedures, to address the trend. The inspectors have observed measurable improvement in the identification of issues and the use of CAP evaluations. An adverse trend was noted with the integrated control system unit load demand module tripping to manual (IR 1511473). Exelon has an open troubleshooting matrix to support further evaluation.
The inspectors noted TMI now more clearly documents operating experience with respect to defects reported to the NRC; the licensee documents each reported condition communicated to the station in their CAP for evaluation regardless if it directly affects TMI. Additionally, the inspectors recently observed, consistent with Exelon issue reports, an apparent increase in chemistry performance issues. Exelon has entered these issues in their CAP and has taken immediate management actions to the address the issues.
.3 Annual Sample: Review of Single-Rod Power Supply Failures
a. Inspection Scope
The inspectors performed a review of multiple Single Rod Power Supply (SRPS)failures, similar to those documented in IRs 1449888 and 1436736, of the digital control rod drive system that was installed at the station in November 2011. This system is not safety-related, but throughout the subsequent operating cycle, the station has experienced a high number and rate of SRPS failures. The inspectors reviewed the failures as they occurred and assessed the overall station impact, including Exelons review of the issue. The inspectors evaluated whether station personnel had identified, assessed, and reviewed causal factors leading to these failures and any long-term corrective actions. The inspectors also walked the system in the field and reviewed operating conditions and visually inspected failure power supplies.
b. Findings and Observations
No findings were identified.
The inspectors determined that the majority of the SRPS failures occurred within six months of operation and were attributed to a lower than expected DC voltage on one of three output phases. An adverse trend in SRPS failures was identified by Exelon and documented in IR 1353918. Exelon, with assistance from the vendor, determined that the majority of failures were caused by an internal silicon controlled rectifier failure. The licensee determined that the lower DC phase voltage was below a conservative DC setpoint which actuates the control rod system fault logic and main control room alarm when reached. There are two SRPSs in parallel for each control rod drive mechanism; one SRPS can carry full load. A single SRPS failure to a control rod does not impact plant operations. The licensee has monitored SRPS failure rate, which is still higher than expected, and are proactively planning rectifier replacements for a number of SRPSs. The inspectors review did not identify any issues that would adversely affect the capability of the operators to implement abnormal or emergency operating procedures and concluded Exelons actions are reasonable.
.4 Annual Sample: Review of Integrated Control System (ICS) and Computer-Based
Instrumentation Issues
a. Inspection Scope
The inspectors assessed Exelons review of multiple issues affecting the Integrated Control System (ICS), Primary Plant Computer (PPC), and Fixed Incore Detector Monitoring System (FIDMS). Together these systems provide indication and control capability of the reactor and power conversion systems to the main control room operators. Particularly, issues reviewed were related to an adverse trend in ICS Unit Load Demand (ULD) module tripping to manual control, as documented in IR 1511473, PPC failovers from one server to another as documented in IR 1476473, and FIDMS calculation issue as documented in IR 1514496 or server failure as documented in IR 1514633.
The inspectors assessed Exelons problem identification threshold, cause analyses, extent of condition reviews, compensatory actions, and the prioritization and timeliness of corrective actions to determine whether Exelon was appropriately identifying, characterizing, and correcting problems associated with this issue and whether the planned or completed corrective actions were appropriate. The inspectors compared the actions taken to the requirements of Exelons corrective action program and 10 CFR 50, Appendix B. In addition, the inspectors performed field walkdowns and interviewed personnel to assess the effectiveness of the implemented corrective actions.
b. Findings and Observations
No findings were identified.
Regarding ICS issues, Exelon has appropriately documented and evaluated each issue in CAP and assembled a team composed of other industry ICS users and designers to review TMIs ICS issues and gain information and experience from others. A number of actions resulted from this team, including the establishment of long term ICS reliability preventive maintenance strategy, which would address ICS usability via a combination of comprehensive module refurbishment, re-engineering, or STAR module replacements until an ICS replacement is determined. Other significant actions and recommendations were documented in IR 1420753-12. Exelon continues to experience, troubleshoot, and monitor the ULD module unexpectedly tripping to manual. No definitive cause has been determined, but the licensee documents the circumstances of each occurrence into CAP and continues to troubleshoot the issue.
Regarding PPC issues, Exelon established a PPC team and evaluated each of the PPC failovers, and in aggregate (CCA 1476473), and determined the causes to be either insufficient memory resources or due to obsolete hardware failure. However, a majority of failures were of unknown cause and resulted in requiring field signal cards to be rebooted. The inspectors noted limited diagnostic capabilities exist for the PPC. The licensee has managed the occurrence of PPC issues and has taken actions to balance field inputs and enforce proper program memory management as much as feasibly possible. System engineering continues to monitor PPC performance with Operations and interfaces with a PPC upgrade project manager for future replacement options.
FIDMS issues are interconnected with PPC issues since FIDMS is an application that runs on the PPC to support plant heat balance calculations, among other functions.
The licensee determined that issues experienced with FIDMS are due to the limited resources of the PPC and the method that FIDMS transfers information, via an interfacing file, that may periodically cause FIDMS to lock-up. Exelon has determined that corrective actions for the PPC issues above have minimized this occurrence and that to ultimately correct this issue is to replace or upgrade the PPC hardware. Exelon is planning to replace the PPC in the future and has established a project team to manage this change.
The inspectors reviewed Exelons actions to the issues in aggregate and determined that Exelon has adequately managed the issues and taken appropriate actions to address, in the interim, and planned projects to upgrade hardware in the long term. The inspectors determined Exelons overall response to the issue was commensurate with the safety significance, was timely, and included appropriate compensatory actions.
4OA3 Follow-Up of Events and Notices of Enforcement Discretion
.1 (Closed) Licensee Event Report (LER) 05000289/2012-002-00: Missing Seals in Air
Intake Tunnel Conduits
On August 10, 2012, it was discovered during a flood protection barrier walkdown that conduits carrying cables through the Air Intake Tunnel (AIT) to the auxiliary building did not contain internal flood protection seals. The licensee took immediate compensatory actions and subsequently sealed the conduits as a final corrective action. A root cause evaluation was conducted by the licensee. The enforcement aspects of this issue were previously discussed in reports 05-289/2012005 (ADAMS Accession Nos.
ML13042A277, ML13094A219) and 05-289/2013009 (ADAMS Accession No.
ML13120A040). The inspectors did not identify any new issues during the review of the LER. This LER is closed.
.2 (Closed) LER 05000289/2012-002-01: Missing Seals in Air Intake Tunnel Conduits
On August 10, 2012, it was discovered during a flood protection barrier walkdown that conduits carrying cables through the Air Intake Tunnel (AIT) to the auxiliary building did not contain internal flood protection seals. The licensee took immediate compensatory actions and subsequently sealed the conduits as a final corrective action. A root cause evaluation was conducted by the licensee. Revision 01 of this LER documents the licensee safety significance of the identified issue. The enforcement aspects of this issue were previously discussed in reports 05-289/2012005 (ADAMS Accession Nos.
ML13042A277, ML13094A219) and 05-289/2013009 (ADAMS Accession No.
ML13120A040). The inspectors did not identify any new issues during the review of the LER. This LER is closed.
4OA6 Meetings, Including Exit
On July 19, 2013, the inspectors presented the inspection results to Mr. Rick Libra, TMI Site Vice President, and other members of the TMI staff. The inspectors verified that no proprietary information was retained by the inspectors or documented in this report.
ATTACHMENT:
SUPPLEMENTARY INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
R. Libra
Site Vice President
T. Alvey
Manager, Chemistry, Environmental, & Radwaste
D. Atherholt
Manager, Regulatory Assurance
R. Campbell
Manager, Site Security
S. Cvijic
Chemistry Manager
D. Divittore
Manager, Site Radiation Protection
J. Dullinger
Director, Engineering
M. Fitzwater
Senior Regulatory Specialist
T. Haaf
Director, Operations
G. McCarty
Supervisor, Radiation Protection
M. Newcomer
Plant Manager
J. Piazza
Senior Manager, Design Engineering
J. Pickett
Supervisor, Maintenance
J. Popielarski
Director, Work Management
C. Six
Supervisor, Shift Operations
G. Smith
Director, Maintenance
B. Shumaker
Manager, TMI Site Emergency Preparedness
S. Taylor
Engineer, TMI Fire Protection
L. Weber
Environmental Chemist
Other Personnel
D. Dyckman
Nuclear Safety Specialist
Pennsylvania Department of Environmental Protection
Bureau of Radiation Protection
LIST OF ITEMS OPENED, CLOSED, DISCUSSED, AND UPDATED
Closed
- 05000289/2012-002-00 LER Missing Seals in Air Intake Tunnel Conduits (Section 4OA3.1)
- 05000289/2012-002-01 LER Missing Seals in Air Intake Tunnel Conduits (Section 4OA3.2)