IR 05000336/2012002
| ML12114A204 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 04/23/2012 |
| From: | Ronald Bellamy NRC/RGN-I/DRP/PB5 |
| To: | Heacock D Dominion Resources |
| References | |
| IR-12-002 | |
| Download: ML12114A204 (30) | |
Text
April 23, 2012
SUBJECT:
MILLSTONE POWER STATION - NRC INTEGRATED INSPECTION REPORT 05000336/2012002 AND 05000423/2012002
Dear Mr. Heacock:
On March 31, 2012, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Millstone Power Station, Units 2 and 3. The enclosed inspection report documents the inspection results, which were discussed on April 19, 2012 with Mr. Stephen E. Scace, Site Vice President, and other members of your staff.
The inspection examined activities conducted under your license as they relate to safety and compliance with the Commissions rules and regulations and with the conditions of your license.
The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel.
No NRC-identified or self-revealing findings were identified during this inspection.
In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of the NRCs document system (ADAMS). ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,
/RA/
Ronald R. Bellamy, Chief Reactor Projects Branch 5 Division of Reactor Projects
Docket Nos.: 50-336, 50-423 License Nos.: DRP-65, NPF-49
Enclosure:
Inspection Report 05000336/2012002 and 05000423/2012002
w/Attachment: Supplemental Information
REGION I==
Docket Nos.:
50-336, 50-423
License Nos.:
Report No.:
05000336/2012002 and 05000423/2012002
Licensee:
Dominion Nuclear Connecticut, Inc.
Facility:
Millstone Power Station, Units 2 and 3
Location:
P.O. Box 128
Waterford, CT 06385
Dates:
January 1, 2012 through March 31, 2012
Inspectors:
S. Shaffer, Senior Resident Inspector, Division of Reactor Projects (DRP)
J. Krafty, Resident Inspector, DRP
B. Haagensen, Resident Inspector, DRP
E. Burket, Reactor Inspector, Division of Reactor Safety (DRS)
F. Arner, Senior Reactor Inspector, DRS
J. Brand, Reactor Inspector, DRS
J. Furia, Senior Health Physicist, DRS
Approved By:
Ronald R. Bellamy, Chief
Reactor Projects Branch 5
Division of Reactor Projects
Enclosure
SUMMARY OF FINDINGS
IR 05000336/2012002, 05000423/2012002; 1/1/2012-3/31/2012; Millstone Units 2 and 3;
Routine Quarterly Integrated Report
This report covered a three-month period of inspection by resident inspectors and announced inspections performed by regional inspectors. No findings or violations were identified. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 4, dated December 2006.
REPORT DETAILS
Summary of Plant Status
Millstone Unit 2 and Unit 3 began the inspection period operating at 100 percent power. On January 13, both units reduced power because of storm related fouling of the intake structure.
Unit 2 reduced power to 73 percent at 8:45 p.m. and resumed 100 percent power operations at 10:00 p.m. on January 14. Unit 3 reduced power to 80 percent at 8:20 p.m. on January 13 and resumed 100 percent power operations at 5:18 PM on January 14. On January 20, Unit 2 reduced power to 83 percent at 12:00 a.m. to replace seals on the B and C condensate pumps. On January 23, Unit 2 resumed 100 percent power operations at 2:43 a.m. On February 25, Unit 3 reduced power to 75 percent due to environmental factors affecting plant conditions. Unit 3 resumed to 100 percent power operations on February
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
==1R04 Equipment Alignment
Partial System Walkdowns (71111.04Q - 3 samples)
a. Inspection Scope
==
The inspectors performed partial walkdowns of the following systems:
Unit 2
- B Control Room Air Conditioning System (CRAC) while the A CRAC was out of service (OOS) for repairs on March 21
- A Emergency Diesel Generator (EDG) while the B EDG was OOS for surveillance testing on March 28
Unit 3
- Station Blackout (SBO) Diesel on March 30
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 (TS), work orders, condition reports (CR), 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 Dominion staff had properly identified equipment issues and entered them into their corrective action program (CAP) for resolution with the appropriate significance characterization. Documents reviewed for each section of this inspection report are listed in the Attachment.
b. Findings
No findings were identified.
==1R05 Fire Protection
Resident Inspector Quarterly Walkdowns (71111.05Q - 3 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 Dominion 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
- B EDG Compartment, Fire Area A-16
- East DC Switchgear Room, Fire Area A-20
Unit 3
- SBO Diesel and Tank Enclosure, Fire Area SBO-1
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 a licensed operator simulator training for Unit 2 on January 10, which included letdown controller malfunction followed by flooding in the turbine building and a rupture of the auxiliary feed water pump discharge piping. 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.
The inspectors observed licensed operator simulator training for Unit 3 on January 17, which included a loss of condenser vacuum followed by a small break loss of coolant accident. The inspectors evaluated operator performance during the simulated event and verified completion of risk significant operator actions, including the use of abnormal and emergency operating procedures. The inspectors assessed the clarity and effectiveness of communications, implementation of actions in response to alarms and degrading plant conditions, and the oversight and direction provided by the control room supervisor. The inspectors verified the accuracy and timeliness of the emergency classification made by the shift manager and the technical specification action statements entered by the shift technical advisor. Additionally, the inspectors assessed the ability of the crew and training staff to identify and document crew performance problems.
b. Findings
No findings were identified.
.2 Quarterly Review of Licensed Operator Performance in the Main Control Room
a. Inspection Scope
The inspectors observed and reviewed the crews preparations for a potential TS shutdown due to inoperable Unit 3 Steam Generator (SG) pressure transmitters during the evening of February 9 and turbine valve testing on February 17. The inspectors observed infrequently performed tests or evolution briefings, pre-shift briefings, and reactivity control briefings to verify that the briefings met the criteria specified in Dominions Operations Section Expectations Handbook and Dominions Administrative Procedure OP-AA-329, Conduct of Infrequently Performed Tests and Evolutions, Revision 1. Additionally, the inspectors observed test performance to verify that procedure use, crew communications, and coordination of activities between work groups 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 structures, systems, and components (SSC) performance and reliability. The inspectors reviewed system health reports, CAP documents, maintenance work orders, and maintenance rule basis documents to ensure that Dominion was identifying and properly evaluating performance problems within the scope of the maintenance rule. For each sample selected, the inspectors verified that the SSC was properly scoped into the maintenance rule in accordance with 10 CFR 50.65 and verified that the (a)(2) performance criteria established by Dominion 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 Dominion staff was identifying and addressing common cause failures that occurred within and across maintenance rule system boundaries.
Unit 2
- Main Feedwater System
- Radiation Monitoring System
Unit 3
- Auxiliary Feedwater System
- 480 VAC Motor Control Center Breakers
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 Dominion 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 Dominion personnel performed risk assessments as required by 10 CFR 50.65(a)(4) and that the assessments were accurate and complete. When Dominion 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
- Moderate Trip Risk due to maintenance on 345 KV Line 310 which removed Unit 2s output tie to the North Bus on January 9
- Yellow Risk due to the A high pressure safety injection (HPSI) pump being out for testing on January 19
- Increased Trip Risk due to B condensate pump being taken OOS for repair immediately followed by a similar repair on the C condensate pump starting on January 20 and finishing on January 23
- Increased Trip Risk due to A stator cooling pump being replaced on February 7
Unit 3
- Unplanned loss of the A EDG during surveillance testing with the A HPSI pump, B RPCCW pump, and A TBCCW pump OOS on January 18
- Extended maintenance period due to frequency fluctuation on the A EDG during Preventive Maintenance Test (PMT) surveillance on February 21
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:
Unit 2
- CR457554, Terry Turbine HELB door not fully contacting the knife edge
- CR459124, B condensate pump elevated mechanical seal leakage and its associated Operational Decision Making (ODM)
- CR460065, A reactor coolant pump (RCP) motor oil leakage and its associated ODM
Unit 3
- OD000468, A EDG Governor Load Swings
- CR464272, Rosemount Transmitter Part 21
- CR464818, Ground Water Intrusion through ESF Cable Penetrations
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 TS and UFSAR to Dominions 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 Dominion. The inspectors determined, where appropriate, compliance with bounding limitations associated with the evaluations.
b. Findings
No findings were identified.
1R18 Plant Modifications
.1 Temporary Modifications
a. Inspection Scope
The inspectors reviewed a temporary modification to the Unit 3 D SG level transmitter low level setpoint described in Temp Mod 3-12-005, 3FWS*LB547B D SG Level Setpoint Change to determine whether the modification affected the safety functions of systems that are important to safety. The inspectors reviewed 10 CFR 50.59 documentation and post-modification testing results to verify that the temporary modifications did not degrade the design bases, licensing bases, and performance capability of the affected systems.
b. Findings
No findings were identified.
.2 Permanent Modifications
a. Inspection Scope
The inspectors evaluated a modification to the Unit 2 Refueling Water Storage Tank (RWST) remote temperature sensor implemented by design modification package DM2-00-0253-09, Unit 2 RWST RTD Modification. The inspectors reviewed the 10 CFR 50.59 justification and verified that the design bases, licensing bases, TS and performance capability of the affected systems were not degraded by the modification.
In addition, the inspectors reviewed modification design documents associated with the design change for the replacement of the RTD temperature sensor with a modified, flexible RTD and walked down the proposed field installation site.
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 were 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.
Unit 2
- Post Maintenance Test for A stator cooling pump following a motor replacement on February 8
- Post Maintenance Test for A EDG following channel head replacement of the diesel jacket water heat exchanger on February 15
Unit 3
- Post Maintenance Test for the A EDG following routine maintenance and failed fuse replacement on February 21
- C Condensate Pump following replacement on March 3
- Post Maintenance Test for the A EDG sequencer following replacement of the 15 volt and 48 volt power supplies on March 2
- Post Maintenance Test for the A EDG sequencer following the second replacement of the 48 volt power supplies on March 24
- Post Maintenance Test for the TDAFW Pump Governor Speed Setting Issue on March 26
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 TS, the UFSAR, and Dominion 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 2
- SP 2613L, Diesel Generator Slow Start Operability Test, Facility 2, Revision 005-01
- SP 2602A, Reactor Coolant Leakage, Revision 006-02 (RCS Leakage)
- CP 2802N, Primary Systems Sampling and Analysis, Revision 001-03
Unit 3
- CP 3802E, Reactor Coolant Gas Sampling and Analysis, Revision 002-01
- SP 3601F.6, Reactor Coolant System, Water Inventory Measurement, Revision 006-06
b. Findings
No findings were identified.
Cornerstone: Emergency Preparedness
1EP6 Drill Evaluation
Training Observations
a. Inspection Scope
The inspectors observed a simulator training evolution for Unit 3 licensed operators on January 17, which required emergency plan implementation by an operations crew.
Dominion planned for this evolution to be evaluated and included in performance indicator 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 any weaknesses and deficiencies in the crews performance and ensure that Dominion evaluators noted the same issues and entered them into their CAP.
b. Findings
No findings were identified.
RADIATION SAFETY
Cornerstone: Public and Occupational Radiation Safety
2RS0 1 Radiological Hazard Assessment and Exposure Controls
a. Inspection Scope
The inspectors performed walk downs of the Dominion facility, including radioactive waste processing, storage, and handling areas to evaluate material conditions and potential radiological conditions.
The inspectors selected containers holding non-exempt licensed radioactive materials that may cause unplanned or inadvertent exposure of workers, and verified that they were labeled and controlled.
During tours of the facility and review of ongoing work the inspectors evaluated ambient radiological conditions. The inspectors verified that existing conditions were consistent with posted surveys, radiation work permits (RWP), and worker briefings, as applicable.
The inspectors verified that radiation monitoring devices were placed on the individuals body consistent with the method that Dominion was employing to monitor dose from external radiation sources. The inspectors verified that the dosimeter was placed in the location of highest expected dose or that Dominion was properly employing an NRC-approved method of determining effective dose equivalent.
For high-radiation work areas with significant dose rate gradients (a factor of 5 or more),the inspectors reviewed the application of dosimetry to effectively monitor exposure to personnel. The inspectors verified that Dominion controls were adequate.
The inspectors verified that problems associated with radiation monitoring and exposure control were being identified by Dominion at an appropriate threshold and were properly addressed for resolution in their CAP. In addition, the inspectors verified the appropriateness of the corrective actions for a selected sample of problems documented by Dominion that involve radiation monitoring and exposure controls. The inspectors determined that Dominion was assessing the applicability of operating experience to their plants.
b. Findings
No findings were identified.
2RS0 2 Occupational ALARA Planning and Controls
a. Inspection Scope
The inspectors obtained from Dominion a list of work activities ranked by actual or estimated exposure that occurred during the last outage (3R14), and selected work activities of the highest exposure significance.
The inspectors reviewed the as low as reasonably achievable (ALARA) work activity evaluations, exposure estimates, and exposure mitigation requirements. The inspectors determined that Dominion had reasonably grouped the radiological work into work activities, based on historical precedence, industry norms, and/or special circumstances.
The inspectors verified that Dominions planning identified appropriate dose mitigation features considered alternate mitigation features commensurate with the risk of the work activity and defined reasonable dose goals. The inspectors verified that Dominions ALARA assessment had taken into account decreased worker efficiency from use of respiratory protective devices and or heat stress mitigation equipment. The inspectors determined that Dominions work planning considered the use of remote technologies as a means to reduce dose and the use of dose reduction insights from industry operating experience and plant-specific lessons learned. The inspectors verified the integration of ALARA requirements into work procedure and radiation work permit (RWP) documents.
The inspectors compared the results achieved with the intended dose established in Dominions ALARA planning for these work activities. The inspectors compared the person-hour estimates provided by maintenance planning and other groups with the actual work activity performance, and evaluated the accuracy of these time estimates.
The inspectors determined the reasons for any inconsistencies between intended and actual work activity doses. The inspectors focused on those work activities with planned or accrued exposure greater than 5 person-rem (Boric Acid Corrosion Control Program, insulation, mechanical maintenance, reactor disassembly/reassembly, scaffolding, SG work, and valve repairs).
The inspectors determined that post-job reviews were conducted and all issues identified were entered into Dominions CAP.
The inspectors evaluated Dominions method of adjusting exposure estimates, or re-planning work, when unexpected changes in scope or emergent work were encountered.
The inspectors determined that adjustments to exposure estimates were based on sound radiation protection and ALARA principles. The inspectors determined whether the frequency of these adjustments question the adequacy of the original ALARA planning process.
The inspectors verified that issues associated with ALARA planning and controls were being identified by Dominion at an appropriate threshold and were properly addressed for resolution in their CAP.
b. Findings
No findings were identified.
2RS0 4 Occupational Dose Assessment
a. Inspection Scope
The inspectors reviewed the most recent National Voluntary Laboratory Accreditation Program (NVLAP) accreditation report pertaining to Dominions dosimetry program.
The inspectors reviewed Dominion procedures associated with dosimetry operations, including issuance/use of external dosimetry, assessment of internal dose, and evaluation of dose assessment for radiological incidents.
The inspectors verified that Dominion had established procedural requirements for determining when external and internal dosimetry was required.
The inspectors verified that Dominions personnel dosimeters that require processing were NVLAP accredited. The inspectors verified the vendors NVLAP accreditation.
The inspectors ensured that the approved irradiation test categories for each type of personnel dosimeter used were consistent with the types and energies of the radiation present, and the way that the dosimeter was being used.
The inspectors selected dosimetry occurrence reports or CAP documents for adverse trends related to electronic dosimeters. The inspectors determined that Dominion had not identified any trends and where appropriate, implemented appropriate corrective actions.
The inspectors reviewed procedures used to assess dose from internally deposited nuclides using whole body counting equipment. The inspectors verified that the procedures addressed methods for determining if an individual was internally or externally contaminated, the release of contaminated individuals, the determination of entry route, and assignment of dose.
The inspectors verified that the frequency of such measurements was consistent with the biological half-life of the potential radionuclides available for intake.
The inspectors evaluated the minimum detectable activity (MDA) of instrument. The inspectors determined that the MDA were adequate to determine the potential for internally deposited radionuclides sufficient to prompt additional investigation.
The inspectors verified that the system used in each bioassay had sufficient counting time/low background to ensure appropriate sensitivity for the potential radionuclides of interest. The inspectors verified that the appropriate radionuclide library was used. The inspectors verified that any anomalous count peaks indicated in each output spectra received appropriate disposition.
The inspectors reviewed the counting laboratorys QA program and verified that if a vendor lab is used, Dominion audits of the lab were conducted. The inspectors verified that the lab participated in an analysis cross-check program and that out-of-tolerance results were evaluated and resolved appropriately.
The inspectors reviewed Dominions methodology for monitoring external dose in situations where non-uniform fields are expected or large dose gradients exist. The inspectors verified that Dominion had established criteria for determining when alternate monitoring techniques were to be implemented.
The inspectors reviewed dose assessments performed using multi-badging during the current assessment period. The inspectors verified that the assessments were performed consistently with Dominion procedures and dosimetric standards.
The inspectors evaluated Dominions neutron dosimetry program, including dosimeter type(s) and/or survey instrumentation.
The inspectors verified that problems associated with occupational dose assessment were being identified by Dominion at an appropriate threshold and were properly addressed for resolution in their CAP. In addition, the inspectors verified the appropriateness of the corrective actions for a selected sample of issues documented by Dominion.
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA1 Performance Indicator Verification
Reactor Coolant System (RCS) Specific Activity and RCS Leak Rate
a. Inspection Scope
The inspectors reviewed Dominions submittal for the RCS specific activity and RCS leak rate performance indicators for both Unit 2 and Unit 3 for the period of January 1, 2011 through December 31, 2011. To determine the accuracy of the performance indicator data reported during those periods, the inspectors used definitions and guidance contained in NEI Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 6. The inspectors also reviewed RCS sample analysis and control room logs of daily measurements for RCS leakage, and compared that information to the data reported by the performance indicator. Additionally, the inspectors observed surveillance activities that determined the RCS identified leakage rate, and chemistry personnel taking and analyzing a RCS sample.
b. Findings
No findings were identified.
4OA2 Problem Identification and Resolution
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 Dominion 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 CAP.
b. Findings
No findings were identified.
4OA5 Other Activities
(Closed) NRC Temporary Instruction 2515/177 - Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal and Containment Spray Systems
a. Inspection Scope
The inspectors performed the inspection at Units 2 and 3 in accordance with Temporary Instruction (TI) 2515/177, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal and Containment Spray Systems. The NRC developed TI 2515/177 to support the NRCs confirmatory review of Dominions responses to NRC Generic Letter (GL) 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal and Containment Spray Systems. Based on a review of Dominions GL 2008-01 response letters, the NRC Office of Nuclear Reactor Regulation (NRR) staff provided additional plant specific guidance on inspection scope to the regional inspectors. The inspectors used this inspection guidance along with the TI to verify that Dominion implemented or was in the process of acceptably implementing the commitments, modifications, and programmatically controlled actions described in their GL 2008-01 response. The inspectors verified that the plant-specific information (including licensing basis documents and design information) was consistent with the information that Dominion submitted to the NRC in response to GL 2008-01.
The inspectors reviewed a sample of isometric drawings, and piping and instrumentation diagrams, and conducted selected system piping walkdowns to verify that Dominions drawings reflected the subject system configurations and UFSAR descriptions.
Specifically, the inspectors verified the following related to a sample of isometric drawings for the safety injection (SI), containment spray, and shutdown cooling systems for Unit 2 and the SI, residual heat removal system, quench spray system, and containment recirculation spray system for Unit 3.
- High point vents were identified
- High points that did not have vents were recognized and evaluated with respect to their potential for gas buildup
- Other areas where gas could accumulate and potentially impact subject system operability, such as orifices in horizontal pipes, isolated branch lines, heat exchangers, improperly sloped piping, and under closed valves, were acceptably evaluated in engineering reviews or had ultrasonic test (UT) points which would reasonably detect void formation
- For piping segments reviewed, branch lines and fittings were clearly shown The inspectors performed walkdowns of portions of the above systems to evaluate the acceptability of Dominions drawings utilized during their review of GL 2008-01. The inspectors verified that Dominion performed walkdowns of the applicable systems to confirm that the combination of system orientation, vents, instructions and procedures, testing, and training, would ensure that each system was sufficiently full of water to ensure operability. The inspectors reviewed Dominions methodology used to determine system piping high points, identification of negative sloped piping, and calculations of void sizes based on UT equipment readings, to ensure the methods were reasonable.
The inspectors also reviewed engineering analyses associated with the development of acceptance criteria for as-found voids. The review included engineering assumptions for void transport and acceptability of void fractions at the suction and discharge piping of the applicable system pumps. In addition, the inspectors verified that Dominion included all emergency core cooling systems, along with supporting systems, within the scope of the GL. The inspectors also observed several field UT measurements of the applicable piping in Unit 3 to assess the adequacy of the monitoring techniques used to ensure system operability.
The inspectors reviewed a sample of Dominions procedures used for filling and venting the systems associated with GL 2008-01 to verify that the procedures were effective in venting or reducing voiding to acceptable levels. The inspectors verified that Dominions venting surveillance frequencies were consistent with TS and associated bases, and the UFSAR. The inspectors reviewed a sample of system venting surveillance results to ensure proper implementation of the surveillance program.
The inspectors reviewed CAP documents to verify that selected actions described in Dominions nine-month and supplemental submittals were acceptably documented including completed actions, and implementation schedule for incomplete actions. The inspectors also verified that the commitments in Dominions submittals were included in the CAP. The inspectors specifically verified the installation of hardware vents, located in the containment spray and emergency core cooling suction header and the safety injection discharge piping, as committed to in Dominions GL response. Additionally, the inspectors reviewed evaluations and corrective actions for various issues Dominion identified during their GL 2008-01 review. The inspectors performed this review to ensure Dominion appropriately evaluated and adequately addressed any gas voiding concerns, including the evaluation of operability for gas voids discovered in the field.
Finally, the inspectors reviewed Dominions training associated with gas accumulation to assess if appropriate training had been provided to the operations and engineering support staff to ensure appropriate awareness of the effects of gas voiding. This completes the inspection requirements for TI 2515/177 at Units 2 and 3.
b. Findings
No findings were identified.
4OA6 Meetings, Including Exit
On April 19, 2012, the inspectors presented the inspection results to Stephen E. Scace, Site Vice President, and other members of the Millstone 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
M. Adams
Plant Manager
L. Armstrong
Manager, Training
R. Arquaro
Unit 3 Shift Manager
G. Auria
Nuclear Chemistry Supervisor
B. Bartron
Supervisor, Licensing
R. Beale
Unit 2 Shift Manager
R. Bonner
Nuclear Engineering Supervisor
R. Burnham
Consulting Engineer
C. Chapin
Assistant Operations Manager
W. Chestnut
Supervisor, Nuclear Shift Operations Unit 2
F. Cietek
Nuclear Engineer, PRA
T. Cleary
Licensing Engineer
G. Closius
Licensing Engineer
L. Crone
Supervisor, Nuclear Chemistry
J. Curling
Manager, Protection Services
G. DAuria
Nuclear Supervisor, Chemistry
P. Dillon
Nuclear Engineer III
J. Dorosky
Health Physicist III
B. Ferguson
Unit 2 Shift Manager
M. Finnegan
Supervisor, Health Physics, ISFSI
A. Gharakhanian
Nuclear Engineer III
W. Gorman
Supervisor, Instrumentation & Control
D. Grindle
Senior Nuclear Instrumentation Technician
J. Grogan
Assistant Operations Manager
K. Grover
Manager, Nuclear Operations
C. Houska
I&C Technician
C. Janus
Nuclear Engineer III
P. Kolz
Nuclear Chemistry Technician
J. Kunze
Supervisor, Nuclear Operations Support
J. Laine
Manager, Radiation Protection/Chemistry
M. Legg
Manager, Nuclear Oversight
M. ONeill
Unit 3 Plant Equipment Operator
R. MacManus
Director, Nuclear Station Safety & Licensing
G. Marshall
Manager, Outage and Planning
R. McDonald
Nuclear Engineer III
H. McKenney
Supervisor Nuclear Operations Support
D. Reed
Unit 3 Shift Manager
R. Riley
Supervisor, Nuclear Shift Operations Unit 3
M. Roche
Senior Nuclear Chemistry Technician
D. Russo
Nuclear Engineer Level III
L. Salyards
Licensing, Nuclear Technology Specialist
J. Semancik
Engineering Director
S. Scace
Site Vice President
C. Sloan
Nuclear Plant Equipment Operator
A. Smith
Asset Management
D. Smith
Manager, Emergency Preparedness
S. Smith
Manager, Engineering
S. Turowski
Supervisor, Health Physics Technical Services
C. Vournazos
IT Specialist, Meteorological Data
B. Wilkens
Site Fire Marshall, Senior Safety Specialist
LIST OF ITEMS OPENED, CLOSED, DISCUSSED, AND UPDATED
Closed
005000336,423/2515/177 TI Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal and Containment Spray Systems (4OA5)