IR 05000289/2015003
| ML15306A380 | |
| Person / Time | |
|---|---|
| Site: | Three Mile Island  |
| Issue date: | 11/02/2015 |
| From: | Silas Kennedy NRC/RGN-I/DRP/PB6 |
| To: | Bryan Hanson Exelon Generation Co, Exelon Nuclear |
| KENNEDY, SR | |
| References | |
| IR 2015003 | |
| Download: ML15306A380 (32) | |
Text
UNITED STATES vember 2, 2015
SUBJECT:
THREE MILE ISLAND STATION, UNIT 1 - INTEGRATED INSPECTION REPORT 5000289/2015003
Dear Mr. Hanson:
On September 30, 2015, 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 October 16, 2015, with Mr. E.
Callan, TMI Site Vice President, and other members of your staff.
NRC inspectors 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.
The inspectors documented one finding of very low safety significance (Green) in this report.
This finding did not involve a violation of NRC requirements.
In accordance with Title 10 of the Code of Federal Regulations 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 NRCs Public Document Room or from the Publicly Available Records component of the NRCs Agencywide Documents Access Management 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/
Silas R. Kennedy, Chief Reactor Projects Branch 6 Division of Reactor Projects Docket No. 50-289 License No. DPR-50
Enclosure:
Inspection Report 05000289/2015003 w/Attachment: Supplementary Information
REGION I==
Docket No: 50-289 License No: DPR-50 Report No: 05000289/2015003 Licensee: Exelon Generation Company Facility: Three Mile Island Station, Unit 1 Location: Middletown, PA 17057 Dates: July 01 through September 30, 2015 Inspectors: D. Werkheiser, Senior Resident Inspector T. Daun, Acting Senior Resident Inspector J. Heinly, Resident Inspector J. Furia, Senior Health Physicist H. Gray, Senior Reactor Inspector M. Modes, Senior Reactor Inspector R. Rolph, Health Physicist Approved by: S. Kennedy, Chief Projects Branch 6 Division of Reactor Projects Enclosure
SUMMARY
IR 05000289/2015003, 07/01/2015-09/30/2015; Three Mile Island, Unit 1, Flood Protection
Measures.
This report covers a three-month period of inspection by resident inspectors and announced inspections performed by regional inspectors. Inspectors identified one finding of very low safety significance (Green). The significance of most findings is indicated by their color (i.e.,
greater than Green, or Green, White, Yellow, Red) and determined using Inspection Manual Chapter (IMC) 0609, Significance Determination Process, dated April 29, 2015. Cross-cutting aspects are determined using IMC 0310, Aspects Within Cross-Cutting Areas, dated December 4, 2014. All violations of Nuclear Regulatory Commission (NRC) requirements are dispositioned in accordance with the NRC Enforcement Policy, dated February 4, 2015. The NRC program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 5.
Cornerstone: Mitigating Systems
- Green.
The inspectors identified a finding because Exelon failed to meet a commitment made during original licensing to mitigate an internal flooding event. Specifically, Exelon committed to making changes to the fire water supply system to mitigate the impact of a pipe rupture in the auxiliary building. The inspectors identified that the commitment actions were not completed and no changes to the commitment were identified. The inspectors determined that the failure to perform the modifications to the fire service system, as committed to the NRC in a letter dated November 10, 1972, was a performance deficiency that was reasonably within its ability to foresee and correct.
Exelon documented the issue in issue report 2544387, performed an immediate operability evaluation, and developed corrective actions to restore compliance with the commitment.
The inspectors determined that the performance deficiency is associated with the Mitigating Systems cornerstone attribute of protection against external factors (internal flood hazard) and is more than minor because it adversely affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the performance deficiency adversely impacted the operators ability to detect and mitigate a fire service system pipe rupture in the safety related auxiliary building. The inspectors utilized IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, to determine the significance of the performance deficiency. The inspectors determined the finding to be of very low safety significance (Green) because the finding is not a design or qualification deficiency, does not represent a loss of system safety function or loss of a single train for greater than its allowed technical specification time, does not result in the loss of a high safety-significant maintenance rule train and does not involve the loss of function to mitigate internal flooding events.
The finding is not assigned a cross-cutting aspect because the performance deficiency occurred during original plant construction and is not indicative of current plant performance. (Section 1R06)
REPORT DETAILS
Summary of Plant Status
Unit 1 began the inspection period at 100 percent power. On July 14, 2015, an automatic runback occurred due to a dropped control rod, and operators stabilized reactor power at approximately 57 percent. To facilitate continued operation during troubleshooting and repairs, operators reduced power to approximately 37 percent. It was determined that a manufacturing defect in the single rod power supply (SRPS) had resulted in an electrical transient, causing power to be lost to the control rod drive for the affected control rod. Following repairs, operators recovered the control rod and returned the unit to 100 percent power on July 17.
On September 5, operators reduced power to 89 percent power for planned turbine valve testing and returned to 100 percent power on September 6. 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
External Flooding
a. Inspection Scope
During the week of July 8, 2015, the inspectors performed an inspection of the external flood protection measures for Three Mile Island (TMI). The inspectors reviewed technical specifications (TSs); procedures; design documents; and the updated final safety analysis report (UFSAR), Chapter 2.4.2.4, which depicted the design flood levels and protection areas containing safety-related equipment, to identify areas that may be affected by internal flooding. The inspectors conducted a general site walkdown of all external areas of the plant, including plant discharge penetrations through the dike to ensure that Exelon erected flood protection measures in accordance with design specifications. The inspectors also reviewed operating procedures for mitigating external flooding during severe weather to determine if Exelon planned or established adequate measures to protect against external flooding events. Documents reviewed for each section of this inspection report are listed in the Attachment.
b. Findings
No findings were identified.
1R04 Equipment Alignment
.1 Partial System Walkdowns
a. Inspection Scope
The inspectors performed partial walkdowns of the following systems:
B control building chiller alignment during A control building chiller planned maintenance on September 1, 2015 Primary instrument air lineup during instrument air leak mitigation in turbine building level 305 and repair on September 14 and 15, 2015 Turbine bypass valve control line-up during main steam valve isolation (MS-V-2A/B)in-service testing on September 21, 2015 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, TSs, work orders, issue 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.
.2 Full System Walkdown
a. Inspection Scope
On August 13, 2015, the inspectors performed a complete system walkdown of accessible portions of the A emergency diesel generator (EDG) to verify the existing equipment lineup was correct. The inspectors reviewed operating procedures, surveillance tests, drawings, equipment line-up check-off lists, and the UFSAR to verify the system was aligned to perform its required safety functions. The inspectors also reviewed electrical power availability, component lubrication and equipment cooling, hanger and support functionality, and operability of support systems. The inspectors examined the material condition of the components and observed operating parameters of equipment to verify that there were no deficiencies. Additionally, the inspectors reviewed a sample of related issue reports and work orders to ensure Exelon appropriately evaluated and resolved any deficiencies.
b. Findings
No findings were identified.
1R05 Fire Protection
Resident Inspector Quarterly Walkdowns (71111.05Q - 5 samples)
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.
B EDG (DG-FA-2) on July 13, 2015 Fuel handling building 281 (FH-FZ-1) on August 27, 2015 Installation of 3-hour fire seal to support Diverse and Flexible Coping Strategies FLEX power conduit installation at penetration No. 1339 (control building 322 elevation) under work order C2033420 on September 18, 2015 Fire protection features supported by and for the B natural draft cooling tower on September 25, 2015 Intermediate building 305 corridor (IB-FZ-5) on September 25, 2015
b. Findings
No findings were identified.
1R06 Flood Protection Measures
Internal Flooding Review
a. Inspection Scope
The inspectors reviewed the UFSAR, site flooding analysis, and plant procedures to assess susceptibilities involving internal flooding. The inspectors also reviewed the corrective action program to determine if Exelon identified and corrected flooding problems and whether operator actions for coping with flooding were adequate. The inspectors also focused their review on non-seismic pipe ruptures in the turbine building and the auxiliary building heat exchanger vault to verify the adequacy of equipment seals located below the flood line, floor and water penetration seals, watertight door seals, common drain lines and sumps, sump pumps, level alarms, control circuits, and temporary or removable flood barriers.
b. Findings
Introduction.
The inspectors identified a green finding because Exelon failed to meet a commitment made during original licensing to mitigate an internal flooding event.
Specifically, Exelon committed to making changes to the fire water supply system to mitigate the impact of a pipe rupture in the auxiliary building. The inspectors identified that the commitment actions were not completed and no changes to the commitment were identified.
Description.
The inspectors review of TMIs internal flooding design basis identified that not all aspects of the sites mitigation strategy had been incorporated into the current UFSAR. Therefore, the inspectors performed a detailed historical review of their design and licensing basis requirements and commitments. The inspectors identified that during original TMI plant licensing, the Atomic Energy Commission requested that Exelon (formerly GPU Nuclear) review the TMI design to determine whether the failure of any non-category I (Seismic) equipment, particularly in the circulating water system and fire protection system, could result in a condition, such as flooding or the release of chemicals, that might potentially adversely affect the performance of safety-related equipment required for safe shutdown of the facilities or to limit the consequences of an accident. Exelons review, in part, identified a vulnerability in the auxiliary building where a 12 fire main rupture had the potential to impact safety related equipment. In response to the vulnerability, Exelon committed to making three modifications to the plant to minimize the threat and provide additional operator alarms.
Specifically, Exelon committed to relocating a fire service system branch connection outside of the auxiliary building, installing orifices and a low pressure switch just outside of the auxiliary building, and adding a low pressure alarm indication to alert the operators of a fire main pipe rupture. This commitment was referenced in the original plant safety evaluation report that supported the issuance of TMIs operating license.
The inspectors performed detailed design drawing reviews and walkdowns of the fire service system in the auxiliary building. The inspectors identified that the committed changes to the fire service system, as mentioned above, were not completed and the current fire main rupture mitigation strategy was not consistent with their original licensing basis commitment. Exelon documented the issue in issue report 2544387 and performed an immediate operability evaluation. Operability of the auxiliary building safety related systems, structures and components (SSCs) were supported by crediting existing control room alarms and field operators to identify any fire service system leaks before safety related equipment would be impacted. Furthermore, Exelon has corrective actions planned to restore compliance with the commitment.
Analysis.
The inspectors determined that the failure to perform the modifications to the fire service system, as committed to the NRC in a letter dated November 10, 1972, was a performance deficiency that was reasonably within its ability to foresee and correct, and should have been prevented. Using IMC 0612, Appendix A, Issue Screening, the inspectors determined that the performance deficiency is associated with the Mitigating Systems cornerstone attribute of protection against external factors (internal flood hazard) and is more than minor because it adversely affected the cornerstone objective of ensuring the availability, reliability and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the performance deficiency adversely impacted the operators ability to detect and mitigate a fire service system pipe rupture in the safety related auxiliary building.
The inspectors utilized IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, to determine the significance of the performance deficiency. The inspectors determined the finding to be of very low safety significance (Green) because the finding is not a design or qualification deficiency, does not represent a loss of system safety function or loss of a single train for greater than its allowed technical specification time, does not result in the loss of a high safety-significant maintenance rule train and does not involve the loss of function to mitigate internal flooding events.
The finding is not assigned a cross-cutting aspect because the performance deficiency occurred during original plant construction and is not indicative of current plant performance.
Enforcement.
No violation of NRC regulatory requirements occurred. However, Exelons letter regarding internal flooding evaluation contained a commitment that was not met which constituted a performance deficiency and a finding. This finding is of very low safety significance and has been entered into Exelons corrective action program (issue report 2544387). (FIN 05000289/2015003-01, Internal Flooding Licensing Basis Commitment Not Met)
1R08 Inservice Inspection Activities
Steam Generator Tube Inspection Activities
a. Inspection Scope
Three Mile Island Station, Steam Generator Tube eddy current testing preparation for the Unit 1, 21st refueling outage During the TMI, 20th refueling outage (1R20), Exelons staff completed eddy current testing to examine the condition of the tubes in steam generators (SGs) A and B. As a result, they identified indications of increased tube-to-tube support plate wear. NRC inspectors reviewed the examination results and the subsequent SG condition monitoring and operational assessment document completed by Exelon. The results of these inspections are documented in NRC inspection reports dated February 10, 2013, and November 13, 2014 (Agencywide Documents Access and Management System ML14041A047 and ML14317A309 respectively).
On July 1, 2015, inspectors met with Exelon staff to discuss plans for SG tube examinations during the TMI 1R21 refueling outage. The inspectors determined Exelon plans to complete eddy current testing examinations, including bobbin coil probe, of 100 percent of the tubes in both the A and B SGs. The inspectors discussed Exelons plans with regard to industry SG examination program guidelines and the requirements of TMIs technical specifications.
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 August 4, 2015, which included a loss of coolant accident that resulted in a loss of subcooling margin and the failure of select components to automatically start as required. 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 TS 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 in support of recovering a dropped control rod and power escalation conducted on July 16 and July 17, 2015. 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 000. In addition, the inspectors verified that Exelon 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, 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 Code of Federal Regulations (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 Exelons staff was identifying and addressing common cause failures that occurred within and across maintenance rule system boundaries.
Control tower chiller maintenance on July 21, 2015 Control rod system (system 622) due to digital control drive control system SRPS system failure for control rod 5-1 on July, 30, 2015 Engineered Safeguards Activation System (ESAS) relay maintenance impact on 4 kilovolt maintenance rule function on September 25, 2015
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 TS requirements and inspected portions of redundant safety systems, when applicable, to verify risk analysis assumptions were valid and applicable requirements were met.
Planned yellow risk for maintenance on 1A building spray pump (BS-P-1A) on July 31, 2015 Planned risk mitigation actions for a B ESAS relay replacement on August 24, 2015 Station risk during planned A station air compressor (IA-P-4) maintenance on September 23, 2015
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:
Power range channel NI-7 with unsatisfactory shift and daily checks for heat balance as documented in issue report 02535427, on July 31, 2015 Aggregate review of operator work-arounds on August 26, 2015 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 TS 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 TSs 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
Permanent Modifications
a. Inspection Scope
The inspectors evaluated a modification to the integrated control system rate-limiter implemented under work order R2255301 on September 6, 2015. The inspectors verified that the design bases, licensing bases, and performance capability of the affected systems were not degraded by the modification. In addition, the inspectors reviewed modification documents associated with the upgrade and design change, including installation of logic jumpers within the system card. The inspectors also reviewed revisions to the control room operating procedure regarding power maneuvers and interviewed engineering and operations personnel to ensure the procedure could be reasonably performed.
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.
ESAS relay replacement (63Z-1B/R-C3B) on July 23, 2015 A control tower chiller planned maintenance outage on September 4, 2015 B EDG ring catcher gasket replacement on September 10, 2015 ESAS relay replacement (63Z-2E/R-B1A) on September 15, 2015
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 TSs, 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:
C reactor protection system high flux trip setpoint change and nuclear instrumentation calibration on July 21, 2015 1410-T-1, tank inspection of fire service altitude tank (FS-T-1) on July 22, 2015 (in-service test)
ST 1306-4.16, EDG (EG-Y-1A) monthly test on August 6, 2015 1450-001, 4160 volt motor feeder breaker functional test on September 8, 2015 ST 1303-13.4, remote shutdown system functional test of the B EDG output breaker (G11-02) under work order R2226832 on September 18, 2015
b. Findings
No findings were identified.
Cornerstone: Emergency Preparedness
1EP6 Drill Evaluation
.1 Emergency Preparedness Drill Observation
a. Inspection Scope
The inspectors evaluated the conduct of a routine Exelon emergency drill on July 28, 2015, to identify any weaknesses and deficiencies in the classification, notification, and protective action recommendation development activities. The inspectors observed emergency response operations in the simulator and technical support center to determine whether the event classification, notifications, and protective action recommendations were performed in accordance with procedures. The inspectors also attended the station drill critique to compare inspector observations with those identified by Exelon staff in order to evaluate Exelons critique and to verify whether the Exelon staff was properly identifying weaknesses and entering them into the corrective action program.
b. Findings
No findings were identified.
RADIATION SAFETY
Cornerstone: Occupational and Public Radiation Safety
2RS1 Radiological Hazard Assessment and Exposure Controls
a. Inspection Scope
The inspectors reviewed Exelons performance in assessing and controlling radiological hazards in the workplace. The inspectors used the requirements contained in 10 CFR 20, TSs, applicable Regulatory Guides (RGs), and the procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors reviewed the performance indicators for the occupational exposure cornerstone, radiation protection program audits, and reports of operational occurrences in occupational radiation safety since the last inspection.
Radiological Hazard Assessment The inspectors reviewed recent plant radiation surveys and any changes to plant operations since the last inspection to identify any new radiological hazards for onsite workers or members of the public.
Instructions to Workers The inspectors reviewed several occurrences where a workers electronic personal dosimeter alarmed. The inspectors reviewed Exelons evaluation of the incidents, documentation in the corrective action program, and whether compensatory dose evaluations were conducted when appropriate.
Contamination and Radioactive Material Control The inspectors observed the monitoring of potentially contaminated material leaving the radiological control area and inspected the methods and radiation monitoring instrumentation used for control, survey, and release of that material.
Radiological Hazards Control and Work Coverage The inspectors evaluated in-plant radiological conditions during facility walk-downs and observation of radiological work activities. The inspectors assessed whether posted surveys, radiation work permits, worker radiological briefings, the use of continuous air monitoring and dosimetry monitoring were consistent with the present conditions. The inspectors examined the posting and physical controls for selected high radiation areas (HRAs) and locked high radiation areas to verify conformance with the occupational performance indicator.
Risk-Significant HRA and Very High Radiation Area (VHRA) Controls The inspectors reviewed the controls and procedures for HRAs, VHRAs, and radiological transient areas in the plant.
Problem Identification and Resolution The inspectors evaluated whether problems associated with radiation monitoring and exposure control were identified at an appropriate threshold and properly addressed in the corrective action program.
b. Findings
No findings were identified.
2RS2 Occupational ALARA Planning and Controls
a. Inspection Scope
The inspectors assessed Exelons performance with respect to maintaining occupational individual and collective radiation exposures as low as is reasonably achievable (ALARA). The inspectors used the requirements contained in 10 CFR 20, applicable RGs, TSs, and procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors conducted a review of TMIs collective dose history and trends; ongoing and planned radiological work activities; radiological source term history and trends; and ALARA dose estimating and tracking procedures.
Verification of Dose Estimates and Exposure Tracking Systems The inspectors reviewed the current annual collective dose estimate; basis methodology; and measures to track, trend, and reduce occupational doses for ongoing work activities.
Source Term Reduction and Control The inspectors reviewed the current plant radiological source term and historical trend, plans for plant source term reduction, and contingency plans for changes in the source term as the result of changes in plant fuel performance or changes in plant primary chemistry.
Problem Identification and Resolution The inspectors evaluated whether problems associated with ALARA planning and controls were identified at an appropriate threshold and properly addressed in the corrective action program.
b. Findings
No findings were identified.
2RS4 Occupational Dose Assessment
a. Inspection Scope
The inspectors reviewed the monitoring, assessment, and reporting of occupational dose. The inspectors used the requirements in 10 CFR 20, RGs, TSs, and procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors reviewed: radiation protection program audits, National Voluntary Laboratory Accreditation Program (NVLAP) dosimetry testing reports, and procedures associated with dosimetry operations.
External Dosimetry The inspectors reviewed: dosimetry NVLAP accreditation; onsite storage of dosimeters; the use of correction factors to align electronic personal dosimeter results with NVLAP dosimetry results; dosimetry occurrence reports; and corrective action program documents for adverse trends related to external dosimetry.
b. Findings
No findings were identified.
2RS7 Radiological Environmental Monitoring Program
a. Inspection Scope
The inspectors reviewed the radiological environment monitoring program (REMP) to validate the effectiveness of the radioactive gaseous and liquid effluent release program. The inspectors used the requirements in 10 CFR 20; 40 CFR 190; 10 CFR 50 Appendix I; and the sites TSs, Offsite Dose Calculation Manual (ODCM), and procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors reviewed: Exelon - Three Mile Island 2013 and 2014 annual radiological environmental reports, REMP program audits, ODCM changes, land use census, and inter-laboratory comparison program results.
Onsite Inspection The inspectors reviewed and/or observed the following:
Sample collection, monitoring, and dose measurement stations (e.g.,
thermoluminescent dosimeter, air monitoring, vegetation, milk)
Calibration and maintenance records for air sample and dosimetry measurement equipment Environmental sampling of the effluent release pathways specified in the ODCM Meteorological tower and meteorological data readouts Meteorological instrument operability status and calibration results Missed and anomalous environmental samples identified, resolved, and reported in the annual radioactive environmental monitoring report Positive environmental sample assessment results The groundwater monitoring program as it applies to selected potential leaking SSCs 10 CFR 50.75(g) records of leaks, spills, and remediation since the previous inspection Changes to the ODCM due to changes to the land use census, long-term meteorological conditions, and/or modifications to the environmental sample stations Environmental sample laboratory analysis results, and measurement detection sensitivities Results of the laboratory quality control program audit, and the inter-and intra-laboratory comparison program results Identification and Resolution of Problems The inspectors evaluated whether problems associated with the REMP were identified at an appropriate threshold and properly addressed in TMIs corrective action program.
b. Findings
No findings were identified.
2RS8 Radioactive Solid Waste Processing and Radioactive Material Handling, Storage, and
Transportation (71124.08 - 1 sample)
a. Inspection Scope
The inspectors verified the effectiveness of TMIs programs for processing, handling, storage, and transportation of radioactive material. The inspectors used the requirements of 49 CFR 170-177; 10 CFR 20, 37, 61, and 71; applicable industry standards; RGs, and procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors conducted an in-office review of the solid radioactive waste system description in the UFSAR, the process control program, and the recent radiological effluent release report for information on the types, amounts, and processing of radioactive waste disposed. The inspectors reviewed the scope of quality assurance audits performed for this area since the last inspection.
Radioactive Material Storage The inspectors observed radioactive waste container storage areas and verified that TMI had established a process for monitoring the impact of long-term storage of the waste.
Radioactive Waste System Walk-down The inspectors walked down the following items and areas:
Accessible portions of liquid and solid radioactive waste processing systems to verify current system alignment and material condition Abandoned in place radioactive waste processing equipment to review the controls in place to ensure protection of personnel Changes made to the radioactive waste processing systems since the last inspection Processes for transferring radioactive waste resin and/or sludge discharges into shipping/disposal containers Current methods and procedures for dewatering waste Waste Characterization and Classification The inspectors identified radioactive waste streams and reviewed radiochemical sample analysis results to support radioactive waste characterization. The inspectors reviewed the use of scaling factors and calculations to account for difficult-to-measure radionuclides.
Shipment Preparation The inspectors reviewed the records of shipment packaging, surveying, labeling, marking, placarding, vehicle checks, emergency instructions, disposal manifest, shipping papers provided to the driver, and licensee verification of shipment readiness.
Shipping Records The inspectors reviewed selected non-excepted package shipment records.
Identification and Resolution of Problems The inspectors assessed whether problems associated with radioactive waste processing, handling, storage, and transportation, were identified at an appropriate threshold and properly addressed in TMIs corrective action program.
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA1 Performance Indicator Verification
.1 Radiological Effluent TS/ODCM Radiological Effluent Occurrences (1 sample)
a. Inspection Scope
The inspectors reviewed licensee submittals for the radiological effluent TS/ODCM radiological effluent occurrences performance indicator (PI) for the 1st and 2nd quarter 2015. The inspectors used PI definitions and guidance contained in Nuclear Energy Institute (NEI) 99-02, Revision 7, to determine if the PI data was reported properly. The inspectors reviewed the public dose assessments for the PI for public radiation safety to determine if related data was accurately calculated and reported.
The inspectors reviewed the corrective action program database to identify any potential occurrences such as unmonitored, uncontrolled, or improperly calculated effluent releases that may have impacted offsite dose. The inspectors reviewed gaseous and liquid effluent summary data and the results of associated offsite dose calculations to determine if indicator results were accurately reported.
b. Findings
No findings were identified.
.2 Safety System Functional Failures (1 sample)
a. Inspection Scope
The inspectors sampled Exelons submittals for the Safety System Functional Failures PI for TMI for the period of July 1, 2014 through September 30, 2015. To determine the accuracy of the PI data reported during those periods, inspectors used definitions and guidance contained in NEI 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7, and NUREG-1022, Event Reporting Guidelines 10 CFR 50.72 and 10 CFR 50.73." The inspectors reviewed Exelons operator narrative logs, operability assessments, maintenance rule records, maintenance work orders, issue reports, event reports and NRC integrated inspection reports to validate the accuracy of the submittals.
b. Findings
No findings were identified.
.3 Mitigating Systems Performance Index (5 samples)
a. Inspection Scope
The inspectors reviewed Exelons submittal of the mitigating systems PI for the following systems for the period of July 1, 2014 through September 30, 2014:
[MS 06] Emergency AC Power System (EDGs)
[MS 07] High Pressure Safety Injection System (Make-up)
[MS 08] Emergency Feedwater System
[MS 09] Decay Heat Removal
[MS 10] Cooling Water Support Systems (Decay Closed, Decay River, Nuclear Closed, Nuclear River)
To determine the accuracy of the performance indicator data reported during those periods, the inspectors used definitions and guidance contained in NEI 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7. The inspectors also reviewed Exelons operator narrative logs, issue reports, mitigating systems performance index derivation reports, event reports, and NRC integrated inspection reports to validate the accuracy of the submittals.
b. 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 Annual Sample: A Building Spray Pump (BS-P-1A) Oil Leak
a. Inspection Scope
The inspectors performed an in-depth review of Exelons troubleshooting and corrective actions associated with issue report 2473412, building spray pump 1A oil leakage at 6.6 drops per minute. Specifically, the A building spray pump (BS-P-1A) developed an oil leak from the inboard bearing lip seal during a routine surveillance test.
The inspectors assessed Exelons problem identification threshold, cause analyses, extent of condition reviews, compensatory actions, and the prioritization and timeliness of Exelons 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 engineering personnel to assess the effectiveness of the implemented corrective actions.
b. Findings and Observations
No findings were identified.
Exelon performed extensive troubleshooting to determine the cause and appropriate corrective actions of the BS-P-1A bearing housing oil leak. Exelon performed an in-depth design review and precise in-field measurements that focused on the oil level, seal condition, operational practices and potentially degraded components that would result in the observed leakage. A prompt operability assessment concluded that the pump would remain operable given that the leakage rate remained below 7.5 drops per minute.
Operator rounds were enhanced to ensure oil leakage remained in the operable region throughout the troubleshooting and repair period.
The safety-related building spray system is designed to mitigate the peak pressure transient in the reactor building during a large break loss of cooling accident.
Specifically, the building spray system contains two fully redundant motor driven pumps to spray water through ring headers at the highest elevation in the reactor building to reduce building pressure. The building spray pump bearings are contained in a housing with a passive constant level oiler.
Exelons troubleshooting identified multiple potential causes for the oil leakage such as degraded oil housing lip seal, overfilled housing, or a housing internal degraded condition. Exelon replaced the lip seal, constant level oiler and performed an internal inspection of the bearing housing and did not identify any obvious degraded conditions.
The oil leak continued to persist as identified through post-maintenance testing. Exelon engaged the vendor, Flowserve, for further troubleshooting and failure-mode analysis assistance. Based upon their collective review, it was determined that the most likely cause was due to a degraded lip seal. The lip seals are delicate and are prone to damage during installation. Therefore, TMI replaced the lip seal with a more reliable labyrinth seal design that had proven reliable on similar pump designs at TMI and significantly less susceptible to damage during installation. The post maintenance test and subsequent surveillance tests on BS-P-1A has shown consistent zero oil leakage performance.
The inspectors reviewed Exelons prompt operability determination, augmented operator rounds, troubleshooting activities, and repair activities. The inspectors determined Exelons overall response to the issue was commensurate with the safety significance, was timely, and included appropriate compensatory actions. In addition, the inspectors reviewed the alternate labyrinth seal design for any adverse impact on BS-P-1A and identified no issues of concern.
4OA3 Follow-Up of Events and Notices of Enforcement Discretion
Plant Events
a. Inspection Scope
For the 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 IMC 0309, Reactive Inspection Decision Basis for Reactors, for consideration of potential reactive inspection activities. As applicable, the inspectors verified that Exelon made appropriate emergency classification assessments and properly reported the event in accordance with 10 CFR 50.72 and 50.73. The inspectors reviewed Exelons follow-up actions related to the events to assure that Exelon implemented appropriate corrective actions commensurate with their safety significance.
Dropped control rod 5-1 due to failed control rod drive mechanism SRPSs and resulting main turbine runback on July 14, 2015
b. Findings
No findings were identified.
4OA6 Meetings, Including Exit
On October 16, 2015, the inspectors presented the inspection results to Mr. Edward Callan, 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
- T. Alvey Manager, Chemistry
- D. Atherholt Manager, Regulatory Assurance
T. Bradley Normndeau Associates
- R. Campbell Manager, Site Security
- D. Divittore Manager, Radiological Engineering
- M. Fitzwater Senior Engineer, TMI Regulatory Assurance
- L. Friant Steam Generator Engineer, Exelon Corporate
T. Heindl Steam Generator Engineer
- G. McCarty Manager, Radiological Engineering
- J. Piazza Senior Manager, Design Engineering
- T. Roberts Manager, Radiation Protection Technical Support
- C. Sinn Shipper, Radiological Waste
- G. Smith Director, Maintenance
- M. Torborg Manager, Programs Engineering
- L. Weber Technical Services, Chemistry
LIST OF ITEMS OPENED, CLOSED, DISCUSSED, AND UPDATED
Opened/Closed
- 05000289/2015003-01 FIN Internal Flooding Licensing Basis Commitment Not Met (Section 1R06)