IR 05000220/2017003
| ML17313A215 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 11/09/2017 |
| From: | Anthony Dimitriadis Reactor Projects Branch 1 |
| To: | Bryan Hanson Exelon Generation Co, Exelon Nuclear |
| References | |
| IR 2017003 | |
| Download: ML17313A215 (33) | |
Text
Addressee (First Ini UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION I
2100 RENAISSANCE BLVD., Suite 100 KING OF PRUSSIA, PA 19406-2713 November 9, 2017 Mr. Bryan Senior Vice President, Exelon Generation Company, LLC President and Chief Nuclear Officer, Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555 SUBJECT: NINE MILE POINT NUCLEAR STATION - INTEGRATED INSPECTION REPORT 05000220/2017003 AND 05000410/2017003
Dear Mr. Hanson:
On September 30, 2017, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Nine Mile Point Nuclear Station, LLC (NMPNS), Units 1 and 2. On October 25, 2017, the NRC inspectors discussed the results of this inspection with Mr. Peter Orphanos, Site Vice President, and other members of your staff. The results of this inspection are documented in the enclosed report.
The NRC inspectors did not identify any finding or violation of more than minor significance.
This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and the NRC Public Document Room in accordance with 10 CFR 2.390, Public Inspections, Exemptions, Requests for Withholding.
Sincerely,
/RA/
Anthony Dimitriadis, Chief Reactor Projects Branch 1 Division of Reactor Projects Docket Nos. 50-220 and 50-410 License Nos. DPR-63 and NPF-69
Enclosure:
Inspection Report 05000220/2017003 and 05000410/2017003 w/Attachment: Supplementary Information
REGION I==
Docket Nos. 50-220 and 50-410 License Nos. DPR-63 and NPF-69 Report Nos. 05000220/2017003 and 05000410/2017003 Licensee: Exelon Generation Company, LLC (Exelon)
Facility: Nine Mile Point Nuclear Station, LLC (NMPNS)
Units 1 and 2 Location: Oswego, New York Dates: July 1, 2017 through September 30, 2017 Inspectors: E. Miller, Senior Resident Inspector G. Stock, Resident Inspector R. Rolph, Health Physicist S. Rutenkroger, Senior Resident Inspector C. Safouri, Project Engineer A. Turilin, Project Engineer Approved by: Anthony Dimitriadis, Chief Reactor Projects Branch 1 Division of Reactor Projects Enclosure
TABLE OF CONTENTS 1. REACTOR SAFETY ........................................................................................................... 4 1R04 Equipment Alignment ............................................................................................ 4 1R05 Fire Protection ...................................................................................................... 5 1R06 Flood Protection Measures ................................................................................... 6 1R11 Licensed Operator Requalification Program & Licensed Operator Performance ... 6 1R12 Maintenance Effectiveness ................................................................................... 7 1R13 Maintenance Risk Assessments and Emergent Work Control ............................... 8 1R15 Operability Determinations and Functionality Assessments .................................. 8 1R18 Plant Modifications ................................................................................................ 9 1R19 Post-Maintenance Testing ....................................................................................10 1R20 Refueling and Other Outage Activities .................................................................10 1R22 Surveillance Testing .............................................................................................11 1EP6 Drill Evaluation .....................................................................................................12 2. RADIATION SAFETY ........................................................................................................12 2RS1 Radiological Hazard Assessment and Exposure Controls ....................................12 2RS2 Occupational ALARA Planning and Controls ........................................................13 2RS4 Occupational Dose Assessment...........................................................................14 2RS5 Radiation Monitoring Instrumentation ...................................................................14 4. OTHER ACTIVITIES .........................................................................................................16 4OA1 Performance Indicator Verification .......................................................................16 4OA2 Problem Identification and Resolution ..................................................................17 4OA3 Follow-Up of Events and Notices of Enforcement Discretion................................19 4OA6 Meetings, Including Exit .......................................................................................20 ATTACHMENT: SUPPLEMENTARY INFORMATION ...............................................................20 SUPPLEMENTARY INFORMATION ....................................................................................... A-1 KEY POINTS OF CONTACT ................................................................................................... A-1 LIST OF ITEMS OPENED, CLOSED AND DISCUSSED ........................................................ A-1 LIST OF ITEMS OPENED, CLOSED AND DISCUSSED ........................................................ A-1 LIST OF DOCUMENTS REVIEWED ....................................................................................... A-2 LIST OF ACRONYMS ........................................................................................................... A-11
SUMMARY
Inspection Report 05000220/2017003 and 05000410/2017003; 07/01/2017 - 09/30/2017; Nine
Mile Point Nuclear Station (NMPNS), Units 1 and 2; Routine Integrated Inspection Report.
This report covered a 3-month period of inspection by resident inspectors and announced inspections performed by regional inspectors. No findings were identified. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 6.
REPORT DETAILS
Summary of Plant Status
Unit 1 began the inspection period at 100 percent power. On September 6, 2017, Unit 1 experienced an automatic scram on low reactor water level due to a failure of a feedwater level control component. On September 9, following troubleshooting and repairs of the feedwater level control system, operators started up the unit and raised reactor power to 100 percent. On September 10, operators reduced reactor power to 83 percent to perform a rod pattern adjustment; operators restored reactor power to 100 percent later that same day. Unit 1 remained at or near 100 percent power for the remainder of the inspection period.
Unit 2 began the inspection period at 100 percent power. On July 1, 2017, operators reduced reactor power to 81 percent due to a malfunction associated with the moisture separator reheater (MSR) drain tank level control system. Following repairs on July 3, operators restored reactor power to 100 percent. On July 13, power was reduced to 49 percent when Unit 2 experienced a rupture of an instrument air line and subsequent trip of a feedwater pump.
On July 14, following repairs of the ruptured instrument air line, operators restored power to 100 percent. On August 4, operators reduced reactor power to 20 percent to perform repairs to the main turbine overspeed trip protection system. On August 5, following repairs to the main turbine overspeed trip protection system, operators raised power to 85 percent to perform turbine stop valve and control valve testing. During testing on August 5, Unit 2 experienced an automatic reactor scram on high reactor pressure when turbine control valves unexpectedly went closed. On August 8, following troubleshooting and repairs of the turbine control valve system, operators began power ascension and achieved criticality. On August 9, operators raised reactor power to 100 percent. On August 9, operators reduced reactor power to 85 percent when they experienced a reduction in main condenser vacuum caused by a valve malfunction in the offgas system and leakby of a safety relief valve in the main turbine gland seal system. On August 9, operators reduced reactor power to 80 percent to perform a rod pattern adjustment. On August 10, following repairs to the offgas system valve and main turbine gland seal safety relief valve, operators restored reactor power to 100 percent. Unit 2 remained at or near 100 percent for the remainder of the inspection period.
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
1R04 Equipment Alignment
Partial System Walkdowns (71111.04 - 3 samples)
a. Inspection Scope
The inspectors performed partial walkdowns of the systems listed below. 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 Updated Final Safety Analysis Report (UFSAR), technical specifications, work orders, issue reports (IRs), and the impact of ongoing work activities on redundant trains of equipment in order to identify conditions that could have impacted the systems performance of its 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 (CAP) for resolution with the appropriate significance characterization.
- Unit 1 122 containment spray system following 122 containment spray heat exchanger preventive maintenance on July 20, 2017
- Unit 2 high pressure core spray (HPCS) following planned maintenance on July 27, 2017
- Unit 2 offgas system during elevated inlet pressures and system flows on August 10, 2017
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.
- Unit 2 south reactor building 306 elevation, fire area (FA) 35, on July 20, 2017
- Unit 2 north reactor building 306 elevation, FA 34, on July 20, 2017
- Unit 1 reactor building west 318 elevation, FA 2 on August 22, 2017
- Unit 1 reactor building west 340 elevation, FA 2 on August 22, 2017
- Unit 1 reactor building west 298 elevation, FA 2 on August 22, 2017
b. Findings
No findings were identified.
1R06 Flood Protection Measures
a. Inspection Scope
The inspectors reviewed the Updated Final Safety Analysis Report (UFSAR), the site flooding analysis, and plant procedures to identify internal flooding susceptibilities for the site. The inspectors review focused on the domestic water line to eyewash station in Unit 2 Division II emergency switchgear room. The inspectors verified the adequacy of equipment seals located below the flood line, watertight door seals, common drain lines and sumps, sump pumps, level alarms, control circuits, and temporary or removable flood barriers. The inspectors assessed the adequacy of operator actions that Exelon had identified as necessary to cope with flooding in this area and also reviewed the CAP to determine if Exelon was identifying and correcting problems associated with both flood mitigation features and site procedures for responding to flooding.
b. Findings
No findings were identified.
1R11 Licensed Operator Requalification Program and Licensed Operator Performance
.1 Quarterly Review of Licensed Operator Requalification Testing and Training (2 samples)
a. Inspection Scope
The inspectors observed:
- Unit 1 licensed operator simulator training scenario, which involved a control rod drifting out of position, a loss of 4kV electrical powerboard 101, a loss of coolant accident, and failure of a containment isolation valve on July 11, 2017
- Unit 2 licensed operator simulator training scenario, which involved a loss of turbine building closed loop cooling, a loss of the Division III 4kv electrical bus, a condensate booster pump trip, a dual reactor recirculation pump trip with an anticipated transient without scram, and a loss of coolant accident resulting in a failure of reactor pressure vessel level indication on July 11, 2017 The inspectors evaluated operator performance during the simulated events 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 unit supervisor. The inspectors verified the accuracy and timeliness of the emergency classifications made by the shift manager and the technical specification (TS) action statements by the unit supervisor. 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
(2 samples)
a. Inspection Scope
The inspectors observed:
- Unit 2 during manipulations associated with the MSR drain tank during reduced power operations at 80 percent on July 2, 2017; and during power ascension following corrective maintenance on the MSR equipment on July 3, 2017
- Unit 1 startup following forced outage on September 9, 2017 The inspectors reviewed HU-AA-101, Human Performance Tools and Verification Practices, Revision 009, and observed test performance to verify that procedure use, crew communications, and coordination of plant activities among work groups similarly met established expectations and standards.
b. Findings
No findings were identified.
1R12 Maintenance Effectiveness
a. Inspection Scope
The inspectors reviewed the sample below to assess the effectiveness of maintenance activities on structure, system, and component (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 Title 10 of the Code of Federal Regulations (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 were identifying and addressing common cause failures that occurred within and across maintenance rule system boundaries.
- Unit 1 SF-1154 silicon fluid used for hydraulic snubbers on August 21, 2017
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 from service. 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.
- Unit 2 risk mitigation actions during A residual heat removal (RHR) breaker maintenance on July 19, 2017
- Unit 2 risk mitigation actions during HPCS breaker maintenance on July 24, 2017
- Unit 1 risk mitigation actions during 12 liquid poison system surveillance on August 1, 2017
- Unit 2 Division II emergency diesel generator (EDG) during planned surveillance testing of loss of offsite power/loss of coolant accident relays on August 17, 2017
- Unit 2 A RHR discharge flow switch trip unit calibration on August 24, 2017
- Unit 2 risk mitigation actions during B and C RHR keepfill system relief valve replacement on September 6, 2017
- Unit 2 risk mitigation actions during Division I EDG maintenance window on September 19, 2017
- Unit 1 risk mitigation actions during EDG 102 maintenance window on September 26, 2017
b. Findings
No findings were identified.
1R15 Operability Determinations and Functionality Assessments
a. Inspection Scope
The inspectors reviewed operability determinations for the degraded or non-conforming conditions listed below 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.
The inspectors confirmed, where appropriate, compliance with bounding limitations associated with the evaluations. 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.
- Unit 2 instrumentation associated with reactor water cleanup isolation due to standby liquid control system (SLCS) initiation on July 5, 2017
- Unit 1 EDG 103 during air receiver tank 5 isolation for planned maintenance on July 31, 2017
- Unit 2 Division II EDG due to a failure to run during a monthly surveillance on August 2, 2017
- Unit 2 2MSS*AOV7D, main steam isolation valve 7D following identification 33-6 limit switch not making proper contact on August 10, 2017
- Unit 2 A RHR system following failed as-found surveillance testing of discharge flow transmitter 2RHS*FT86A on August 21, 2017
- Unit 2 failure of reactor manual control system during control rod exercise surveillance testing on August 28 and September 13, 2017
- Unit 1 11 drywell equipment drain tank following level alarm malfunction on September 27, 2017
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.
- Unit 1 seismic qualification of the control room G panel with the average power range monitor drawers racked out for an extended period of time on August 3, 2017
- Unit 2 engineering change package (ECP)-17-000531, temporary modification to reduce the risk of changes in turbine control valve demand signal on August 9, 2017
- Unit 1 ECP-13-000651 and Unit 2 ECP-13-000652, reliable spent fuel pool instrumentation modification on August 28, 2017
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 adequately tested the safety functions that may have been affected by the maintenance activity, that the acceptance criteria in the procedure were consistent with the information in the applicable licensing basis and/or design basis documents, and that the test results were properly reviewed and accepted and problems were appropriately documented. The inspectors also walked down the affected job site, and reviewed test data to verify quality control hold points were performed and checked, and that results adequately demonstrated restoration of the affected safety functions.
- Unit 1 11 reactor building emergency ventilation fan run following fan belt replacement on July 6, 2017
- Unit 1 EDG 103 monthly run following safety valve replacement on starting air receiver 5 on July 10, 2017
- Unit 1 containment spray 122 operability test following heat exchanger and valve preventative maintenance July 13, 2017
- Unit 1 A RHR pump and valve operability test following breaker maintenance on July 20, 2017
- Unit 2 HPCS pump and valve operability test following maintenance on July 26, 2017
- Unit 2 Division II SLCS following oil change and breaker preventive maintenance on August 2, 2017
- Unit 2 2HVC*CAB18A control room air intake radiation monitor following sample pump replacement on August 16, 2017
- Unit 1 turbine stop valve 14 reactor protection limit switch following repairs on September 8, 2017
- Unit 2 Division 2 control room chiller following maintenance and check valve 2SWP*V240B following replacement on September 15, 2017
- EDG 103 following 18-year maintenance window on September 29, 2017
b. Findings
No findings were identified.
1R20 Refueling and Other Outage Activities
a. Inspection Scope
The inspectors reviewed the stations work schedules and outage risk plans for a Unit 2 forced outage August 4-9, 2017, and a Unit 1 forced outage September 6-8, 2017. The inspectors reviewed Exelons development and implementation of outage plans and schedules to verify that risk, industry experience, previous site specific problems, and defense-in-depth were considered. During the outages, the inspectors observed portions of the shutdown and cooldown processes and monitored controls associated with the following outage activities:
- Configuration management, including maintenance of defense-in-depth, commensurate with the outage plan for the key safety functions and compliance with the applicable technical specifications when taking equipment out of service
- Status and configuration of electrical systems and switchyard activities to ensure that technical specifications were met
- Reactor water inventory controls, including flow paths, configurations, alternative means for inventory additions, and controls to prevent inventory loss
- Activities that could affect reactivity
- Identification and resolution of problems related to outage activities
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:
- Unit 1, N1-ST-Q3, High Pressure Coolant Injection Pump and Check Valve Operability Test on July 5, 2017
- Unit 1, N1-ST-Q13, Emergency Service Water Pump and Check Valve Operability Test on August 1, 2017
- Unit 1, N1-ST-Q1A, CS 111 Pump, Valve and shutdown cooling (SDC) Water Seal Check Valve Operability Test on August 22, 2017 (in-service test)
- Unit 2, N2-OSP-EGS-M@002, Diesel Generator and Diesel Air Start Valve Operability Test - Division III on August 23, 2017
b. Findings
No findings were identified.
Cornerstone: Emergency Preparedness
1EP6 Drill Evaluation
Emergency Preparedness Drill Observation
a. Inspection Scope
The inspectors observed a simulator training evolution for Unit 2 licensed operators on July 11, 2017, which required emergency plan implementation by an operations crew.
Exelon planned for this evolution to be evaluated and included in performance indicator (PI) data regarding drill and exercise performance. The inspectors observed event classification and notification activities performed by the crew. The inspectors also attended the post-evolution critique for the scenario. The focus of the inspectors activities was to note if there were any weaknesses and deficiencies in the crews performance and ensure that Exelon evaluators noted the same issues and entered them into the CAP.
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 the monitoring, assessment, and reporting of occupational dose. The inspectors used the requirements in 10 CFR Part 20, Regulatory Guides 8.9 and 8.34, TSs, and procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors reviewed radiation protection program audits and procedures associated with dosimetry operations.
Contamination and Radioactive Material Control (1 sample)
The inspectors observed the monitoring of potentially contaminated material leaving the radiological controlled area and inspected the methods and radiation monitoring instrumentation used for control, survey, and release of that material. The inspectors selected several sealed sources from inventory records and assessed whether the sources were accounted for and were tested for loose surface contamination. The inspectors evaluated whether any recent transactions involving nationally tracked sources were reported in accordance with requirements.
b. Findings
No findings were identified.
2RS2 Occupational As Low As is Reasonably Achievable 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 Part 20, Regulatory Guides 8.8 and 8.10, TSs, and procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors conducted a review of NMPNS collective dose history and trends, ongoing and planned radiological work activities, previous post-outage ALARA reviews, radiological source term history and trends, and ALARA dose estimating and tracking procedures.
Radiological Work Planning (1 sample)
The inspectors selected the following radiological work activities based on exposure significance for review:
- RWP No. NM-1-17-00306, Drywell Scaffolding
- RWP No. NM-1-17-00518, Drywell In-Service-Inspection
- RWP No. NM-1-17-00542, Drywell Recirculation Pump Motor Oil Modification
- RWP No. NM-1-17-00901, Reactor Disassembly and Reassembly
- RWP No. NM-1-17-00601, Reactor Water Clean-Up Maintenance Activities For each of these activities, the inspectors reviewed ALARA work activity evaluations, exposure estimates, exposure reduction requirements, results achieved (dose rate reductions, actual dose), person-hour estimates and results achieved and post-job reviews that were conducted to identify lessons learned.
Implementation of ALARA and Radiological Work Control (1 sample)
The inspectors reviewed radiological work controls and ALARA practices during the observation of in-plant work activities. The inspectors evaluated use of shielding, contamination controls, airborne controls, RWP controls, and other work controls to determine if they were consistent with ALARA plans. The inspectors ensured that work-in-progress reviews were performed in a timely manner and adjustments made to the ALARA estimates when appropriate. The inspectors reviewed the results achieved against the intended ALARA estimates to confirm adequate implementation and oversight of radiological work controls. The inspectors also verified that the ALARA staff was involved with emergent work activities and were revising both dose estimates and ALARA controls in the associated radiation work permits/ALARA plans, as appropriate.
The inspectors reviewed performance in assuring the accuracy and operability of radiation monitoring instruments used to protect occupational workers during plant operations and from postulated accidents. The inspectors used the requirements outlined as listed in 10 CFR Part 20; regulatory guides; American National Standards Institute (ANSI) 323A, N323D, and N42.14; and procedures required by TSs as criteria for determining compliance.
Problem Identification and Resolution (1 sample)
The inspectors evaluated whether problems associated with ALARA planning and controls were identified at an appropriate threshold and properly addressed in the CAP.
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 Part 20, Regulatory Guides 8.9 and 8.34, TSs, and procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors reviewed radiation protection program audits and procedures associated with dosimetry operations.
Source Term Characterization (1 sample)
The inspectors reviewed the plant radiation characterization (including gamma, beta, alpha, and neutron) being monitored. The inspectors verified the use of scaling factors to account for hard-to-detect radionuclides in internal dose assessments.
Internal Dosimetry (1 sample)
The inspectors reviewed internal dosimetry procedures, whole body counter measurement sensitivity and use, adequacy of the program for whole body count monitoring of plant radionuclides or other bioassay technique, adequacy of the program for dose assessments based on air sample monitoring and the use of respiratory protection, and internal dose assessments for any actual internal exposure.
b. Findings
No findings were identified.
2RS5 Radiation Monitoring Instrumentation
a. Inspection Scope
The inspectors reviewed performance in assuring the accuracy and operability of radiation monitoring instruments used to protect occupational workers during plant operations and from postulated accidents. The inspectors used the requirements in 10 CFR Part 20; regulatory guides; ANSI 323A, N323D, and N42.14; and procedures required by TSs as criteria for determining compliance.
Inspection Planning
The inspectors reviewed NMPNS UFSARs, radiation protection audits, records of in-service survey instrumentation, and procedures for instrument source checks and calibrations.
Walkdowns and Observations (1 sample)
The inspectors conducted walkdowns of plant area radiation monitors and continuous air monitors. The inspectors assessed material condition of these instruments and that the monitor configurations aligned with the UFSARs. The inspectors checked the calibration and source check status of various portable radiation survey instruments and contamination detection monitors for personnel and equipment.
Calibration and Testing Program (1 sample)
For the following radiation detection instrumentation, the inspectors reviewed the current detector and electronic channel calibration, functional testing results, alarm set-points, and the use of scaling factors:
- laboratory analytical instruments
- whole body counter
- containment high-range monitors
- personal contamination monitors
- small article monitors
- portable survey instruments
- area radiation monitors
- electronic dosimetry
- air samplers
- continuous air monitors The inspectors reviewed the calibration standards used for portable instrument calibrations and response checks to verify that instruments were calibrated by a facility that used National Institute of Science and Technology traceable sources.
Problem Identification and Resolution (1 sample)
The inspectors verified that problems associated with radiation monitoring instrumentation (including failed calibrations) were identified at an appropriate threshold and properly addressed in the CAP.
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA1 Performance Indicator Verification
.1 Mitigating Systems Performance Index (12 samples)
a. Inspection Scope
The inspectors reviewed Exelons submittal of the Mitigating Systems Performance Index for the following systems for the period of July 1, 2016 through June 30, 2017:
Unit 1 and Unit 2
- Safety System Function Failures (MS05)
- Emergency Alternating Current Power System (MS06)
- High Pressure Injection System (MS07)
- Heat Removal System (MS08)
- Residual Heat Removal System (MS09)
- Cooling Water System (MS10)
To determine the accuracy of the PI data reported during those periods, inspectors used definitions and guidance contained in NEI 99-02, and NUREG-1022, Event Reporting Guidelines: 10 CFR 50.72 and 50.73, Revision 3. The inspectors reviewed Exelons operator narrative logs, operability assessments, maintenance rule records, incident reports, event reports, and NRC integrated inspection reports to validate the accuracy of the submittals.
b. Findings
No findings were identified.
.2 Occupational Exposure Control Effectiveness (1 sample)
a. Inspection Scope
The inspectors reviewed Exelon submittals for the occupational radiological occurrences PI for the first quarter 2016 through the third quarter 2017. The inspectors used PI definitions and guidance contained in NEI 99-02, Revision 7, to determine the accuracy of the PI data reported. The inspectors reviewed electronic personal dosimetry accumulated dose alarms, dose reports, and dose assignments for any intakes that occurred during the time period reviewed to determine if there were potentially unrecognized PI occurrences. The inspectors conducted walkdowns of various locked high and very high radiation area entrances to determine the adequacy of the controls in place for these areas.
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 Exelon entered issues into the CAP 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 condition report screening meetings. The inspectors also confirmed, on a sampling basis, that, as applicable, for identified defects and non-conformances, Exelon performed an evaluation in accordance with 10 CFR Part 21.
b. Findings
No findings were identified.
.2 Annual Sample: Unit 1 Turbine Trip Signal and High Pressure Coolant Injection Initiation
during Tagging Application
a. Inspection Scope
The inspectors performed an in-depth review of the condition that resulted in actuation of the Unit 1 High Pressure Coolant Injection (HPCI) system on March 20, 2017. Exelon provided a 60-day telephone notification to the NRC of this condition reported under 10 CFR 50.73 (a)(2)(iv) due to the invalid actuation of the HPCI flow control mode of the normal feedwater system.
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 appropriately identified, characterized, and corrected problems associated with this issue and whether the planned or completed corrective actions were appropriate. The inspectors compared the actions taken with the requirements of Exelons CAP and 10 CFR Part 50, Appendix B.
In addition, the inspectors reviewed plant parameter data and logs from March 20, 2017 and interviewed operations and engineering personnel to assess the effectiveness of the implemented corrective actions.
b. Findings and Observations
On March 20, 2017, Exelon was performing a shutdown of NMPNS Unit 1 for a planned refueling outage. Exelon removed the main generator, main turbine, and the 13 feedwater pump from service. At Unit 1, the 13 feedwater pump is clutch-driven from the main turbine to provide 100 percent capacity feedwater flow. As part of this evolution, the motor-driven 12 feedwater pump was placed into service and provided normal reactor water level control. At approximately 4 percent reactor power, a clearance tagging evolution was in progress to support shutdown activities. The tag was applied that opened the two output breakers from the automatic voltage regulator (AVR).
Although the main generator and AVR were out of service at this time, the AVR system initiated an internal trip signal from the opening of both output breakers. This trip signal generated a turbine trip signal. The turbine trip signal generated a HPCI initiation signal.
Per design, the 11 and 12 feedwater pumps received start signals, and the feedwater level control system transitioned from normal automatic mode into HPCI mode of operation. The HPCI mode of operation automatically controlled reactor water level at its higher setpoint. The 11 feedwater pump started, and the 12 feedwater pump supplied more water to increase the reactor water level to its setpoint. The operators subsequently secured the 11 feedwater pump and reset HPCI to return to normal automatic control.
Exelon conducted interviews with the operators responsible for the tagging evolution.
Exelon determined that the tagging evolution was based on previous successful experience with tagouts of the AVR system. However, a modification was performed during the last refueling outage which replaced the AVR with a new digital system. The new system included a new feature in which a redundant generator trip signal is generated when the AVR output breakers are both opened. This signal is generated regardless of whether or not the generator and AVR are already tripped. The tagout preparer, reviewer, and shift crew were not aware of the new trip feature.
Since the AVR system was new, Exelon determined that the operators should have questioned the tagout sequence to verify that no adverse consequences would result to or from the AVR system. Exelon briefed operations personnel on this issue and on having a questioning attitude.
Exelon also determined that the new trip information was only contained in the controlled vendor manual. So, Exelon revised the tagout database to flag the relevant AVR components with a notation describing the redundant trip signal with the AVR system either on or off. During tagging development, the notations are required to be reviewed, which will ensure this condition will be recognized during future tagouts involving the AVR system. The inspectors reviewed Exelons corrective actions to address the inadvertent HPCI initiation. The inspectors determined Exelon conducted a thorough technical review of the issue. The inspectors reviewed the tagging database including the relevant components with their notations. The inspectors reviewed the procedures for tagout development. The inspectors determined that Exelons corrective actions were responsive and sufficient and appropriately addressed the deficiency in the tagout process.
However, the inspectors determined that the engineering change which installed the new AVR system was not fully sufficient. The modification process should have determined the need to describe the new redundant trip feature in the procedures or databases used for accomplishing maintenance at NMPNS Unit 1, such as the tagging database. In particular, the inspectors noted that the current engineering change process procedure CC-AA-102, Design Input and Configuration Change Impact Screening, states, in part, if the Configuration Change is revising the basic functions, both the changes and the functions of the modified SSC should be described, including any system interaction changes that are affected by the proposed change. If the use of an SSC has changed, even when the basic function has not changed, then evaluate the effect of the change on the SSC and other SSCs. The inspectors also reviewed the configuration management form for the AVR system modification that was performed in accordance with procedures at the time. The form required operational impacts to be described, including changes to interlocks, control schemes, operational differences, and actuation signal alarm and control functions. As such, this change should have evaluated and described in the applicable procedures or databases the system interrelationship with HPCI and its impact on normal, shutdown, and abnormal operations.
In addition, the inspectors determined that Exelon did not identify or otherwise question whether a deficiency within the engineering change process resulted in an information (readily available procedures and databases) and knowledge gap within the tagout process. Specifically, the inspectors noted that current configuration change procedure, CC-AA-102-F-10A, Operations Department (including Radwaste) Configuration Change Review Checklist, states, in part, that, changes impacting the Clearance and Tagging Program have been identified and are being tracked; and, impact on configuration control and potential configuration control event precursors have been identified and are being addressed. In particular, the inspectors observed that the configuration change process for the AVR system modification did not establish robust barriers to prevent the inadvertent HPCI actuation and relied on a single barrier, a questioning attitude on the part of tagout preparers and verifiers. Exelon initiated IR 4045224 in response to the inspectors observation. The inspectors concluded that Exelons overall response to the invalid HPCI system actuation was commensurate with the safety significance, was timely, and included appropriate compensatory measures.
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 Inspection Manual Chapter (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 Parts 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.
- Unit 2 feedwater pump trip due to instrument airline rupture on July 13, 2017
- Unit 2 automatic reactor scram on high reactor pressure on August 5, 2017
- Unit 2 unexpected loss of condenser vacuum on August 9, 2017
b. Findings
No findings were identified.
4OA6 Meetings, Including Exit
On October 25, 2017, the inspectors presented the inspection results to Mr. Peter Orphanos, Site Vice President, and other members of the NMPNS staff. The inspectors verified that no propriety information was retained by the inspectors or documented in this report.
ATTACHMENT:
SUPPLEMENTARY INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
- P. Orphanos, Site Vice President
- R. Kreider, Plant Manager
- D. Bradshaw, Electrical System Engineer
- R. Bugelholl, Director Site Work Management
- M. Busch, Director Site Maintenance
- C. Christaldi, Senior Radiation Protection Technician
- R. Corcoran, Senior Engineer
- P. Doran, Engineering Manager
- D. Dougherty, Radiation Protection Chief Technician
- B. Geiss, Unit 1 Shift Operations Superintendent
- B. Gover, Senior Radiation Protection Technician
- M. Gray, Manager Site Radiation Protection
- T. Hogan, Radiation Protection Technical Support Manager
- K. James, Reactor Operator
- M. Khan, Director Site Engineering
- K. Kristensen, Regulatory Principle Engineer
- M. Kunzwiler, Manager Site Security
- K. Mattesich, Shift Manager
- D. Moore, Manager Regulatory Assurance
- C. Moorhead, Shift Manager
- S. Nicolaos, Operations Services Manager
- R. Pritchard, Regulatory Specialist
- J. Sawyer, Unit 2 Shift Operations Superintendent
- B. Shultz, Senior Manager Operations Support and Services
- T. Sollenberger, Radiation Protection Supervisor
- V. Svereika, Radiation Protection Chief Technician
- T. Tanguay, Manager Site Chemistry, Environment and Radwaste
- J. Thompson, Director Site Operations
- N. Tryt, Senior Manager Engineering
- J. Tsardakas, Director Site Training
- D. Tulowiecki, Manager Site Maintenance
LIST OF ITEMS
OPENED, CLOSED AND DISCUSSED
Opened/Closed
None
Opened
None
Closed
None