IR 05000336/2014004
| ML14302A535 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 10/27/2014 |
| From: | Raymond Mckinley NRC/RGN-I/DRP/PB5 |
| To: | Heacock D Dominion Resources |
| McKinley R | |
| References | |
| IR 2014004 | |
| Download: ML14302A535 (32) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION I
2100 RENAISSANCE BLVD., SUITE 100 KING OF PRUSSIA, PA 19406-2713 October 27, 2014 Mr. David Heacock President and Chief Nuclear Officer Dominion Resources 5000 Dominion Boulevard Glen Allen, VA 23060-6711 SUBJECT: MILLSTONE POWER STATION - NRC INTEGRATED INSPECTION REPORT 05000336/2014004 AND 05000423/2014004
Dear Mr. Heacock:
On September 30, 2014, 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 October 7, 2014, 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 findings were identified during this inspection.
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 NRC Public Document Room or from the Publicly Available Records component of the NRCs Agencywide Documents Access and 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/
Raymond R. McKinley, Chief Reactor Projects Branch 5 Division of Reactor Projects Docket Nos. 50-336 and 50-423 License Nos. DPR-65 and NPF-49
Enclosure:
Inspection Report 05000336/2014004 and 05000423/2014004 w/Attachment: Supplementary Information
REGION I==
Docket Nos. 50-336 and 50-423 License Nos. DPR-65 and NPF-49 Report Nos. 05000336/2014004 and 05000423/2014004 Licensee: Dominion Nuclear Connecticut, Inc.
Facility: Millstone Power Station, Units 2 and 3 Location: P.O. Box 128 Waterford, CT 06385 Dates: July 1, 2014 through September 30, 2014 Inspectors: J. Ambrosini, Sr. Resident Inspector, Division of Reactor Projects (DRP)
N. Day, Resident Inspector (Acting), DRP B. Haagensen, Resident Inspector, DRP L. McKown, Resident Inspector, DRP J. DeBoer, Project Engineer, DRP S. Shaffer, Senior Project Engineer, DRP Approved By: Raymond R. McKinley, Chief Reactor Projects Branch 5 Division of Reactor Projects Enclosure
SUMMARY
IR 05000336/2014004, 05000423/2014004; 07/01/2014 - 09/30/2014; Millstone Power Station (Millstone) Units 2 and 3, Routine Integrated Inspection Report.
This report covered a three-month period of inspection by resident inspectors and regional project engineers. 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 4.
Other Findings
Two violations of very low safety significance that were identified by Dominion were reviewed by the inspectors. Corrective actions taken or planned by Dominion have been entered into Dominions corrective action program (CAP). These violations and corrective action tracking numbers are listed in Section 4OA7 of this report.
REPORT DETAILS
Summary of Plant Status
Millstone Units 2 and 3 began the inspection period operating at 100 percent power and operated at or near 100 percent power for the period with one exception. On July 26, Unit 2 began a shutdown required by technical specifications (TS) because the turbine-driven auxiliary feedwater pump (TDAFW) was inoperable for greater than the allowed outage time. Unit 2 returned to 100 percent power on July
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
1R01 Adverse Weather Protection
.1 External Flooding
a. Inspection Scope
During the week of August 4, the inspectors performed an inspection of the external flood protection measures for Millstone. The inspectors reviewed TS, procedures, design documents, and the Updated Final Safety Analysis Report (UFSAR), which depicted the design flood levels and protection areas containing safety-related equipment to identify areas that may be affected by external flooding. The inspectors conducted a general site walkdown of external areas of the plant and the emergency diesel generator (EDG) enclosures to ensure that Dominion 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 Dominion 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:
Unit 2 High Pressure Safety Injection, Facility 1, while Facility 2 was out of service for planned surveillance testing on August 12 B EDG due to recent scaffolding setup/removal and painting in the area on August 18 - 20 Unit 3 AC [alternating current) Distribution System Normal and Emergency 4.16 kilovolt buses and 480 volt load centers, during TDAFW pump inoperability for condition monitoring on September 17 The inspectors selected these systems based on their risk-significance relative to the reactor safety cornerstones at the time they were inspected. The inspectors reviewed applicable operating procedures, system diagrams, the UFSAR, Technical Specifications (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 the CAP for resolution with the appropriate significance characterization.
b. Findings
No findings were identified.
1R05 Fire Protection
.1 Resident Inspector Quarterly Walkdowns
a. Inspection Scope
The inspectors conducted tours of the areas listed below to assess the material condition and operational status of fire protection features. The inspectors verified that 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 Reactor Coolant Pump Rebuild Shop Preparation Room, Area A-29 on August 4 West Piping Penetration Area, Area A-8C on August 13 Unit 3 Intake Structure East Service Water Cubicle Area CSW-3 on July 2 Fire Areas EG-3A, North Enclosure, A EDG and EG-4A, South Enclosure, B EDG on July 30 East Switchgear Room (Inverter Room), Area CB-17 on August 7 West Switchgear Room, Area CB-1 on September 17 Engineered Safety Features Building B Motor-Driven Auxiliary Feedpump Cubicle, Area ESF-9 on September 22
b. Findings
No findings were identified.
1R07 Heat Sink Performance (711111.07A - 1 sample)
a. Inspection Scope
The inspectors reviewed the Unit 3 EDG thermal performance test, which tested the jacket water, lube oil cooler, and intercooler heat exchangers to determine readiness and availability to perform safety functions. The inspectors reviewed the design basis for the component and verified Dominions commitments to NRC Generic Letter 89-13. The inspectors observed actual performance tests for the heat exchangers and/or reviewed the results of previous inspections of the A EDG jacket water, intercooler, and lube oil heat exchangers. The inspectors discussed the results of the most recent inspection with engineering staff and reviewed pictures of the as-found and as-left conditions. The inspectors verified that Dominion initiated appropriate corrective actions for identified deficiencies and properly computed the bio-fouling factors. The inspectors also verified that the number of tubes plugged within the heat exchanger did not exceed the maximum amount allowed.
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 Unit 3 licensed operator requalification simulator training on August 6, which included response to a reactor coolant system leak, a failed power range channel nuclear instrument, and a large break loss of coolant accident with containment sump blockage. The inspectors observed Unit 2 licensed operator requalification simulator training on September 25, which included two scenarios. The first scenario began from 100 percent power with the failure of a feedwater heater extraction valve. The crew reduced turbine load using abnormal operating procedure 2525, Rapid Downpower, and stabilized power at 92 percent. Subsequently, the simultaneous failure of the B channel of the reactor protection system caused an anticipated transient without scram and the failure of the D reactor coolant pump seal caused a loss of coolant accident into the reactor building closed cooling water (RBCCW) system which bypassed containment to the auxiliary building. The operators tripped the reactor, initiated a safety injection actuation signal, and manually isolated the leak outside of containment and cooled down the plant. The second scenario began from 100 percent power with an earthquake causing a pressurizer level control failure.
Subsequently, the failure of the circulating water pump caused a loss of condenser vacuum which lead to a reactor trip. The main steam line to #1 Steam Generator (S/G)failed causing a faulted generator and the #2 S/G experienced a tube rupture. 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 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 and reviewed reactor startup activities for Unit 2 on July 29, and July 30, 2014. The inspectors observed the Unit 3 end of life reactor coefficient testing in accordance with SP 31005A, Moderator Temperature Coefficient and Power Coefficient Measurements, Power Exchange Method, during a four hour period on August 8, 2014. The inspectors observed the pre-test 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-100, Conduct of Operations. Additionally, the inspectors observed control room behavior 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.
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 Title 10 of the Code of Federal Regulations (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 Yellow Risk scheduled for concurrent testing of A service water (SW) pump and TDAFW pump on July 11 Yellow Risk scheduled for concurrent C SW strainer overhaul and C RBCCW Pump in-service test on August 11 Yellow Risk scheduled during A EDG post-maintenance testing on September 30 Unit 3 High Risk Contingency Plan for South Bus outage on September 5 Planned entry into Red Risk state following the restoration of the TDAFW pump after the full flow test on September 13 Plant Risk Assessment during performance of TDAFW pump confidence run scheduled concurrent with activities which could challenge S/G Feedwater on September 24
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 CR553433, DB3-201D Battery Cell (Unit 2 Turbine Battery) Temps Above Max Cell Temp of 95 degrees on July 25 CR554612, Terry Turbine failed SP2610BO-002, Quarterly Surveillance, on July 26 CR 548846, Ultrasonic testing of feedwater piping on August 28 Unit 3 ODM000334, 'A power operated relief valve (PORV) Leakage on July 3 CR556453, B EDG crankcase vacuum pump out of service for maintenance on August 25 CR557043, B EDG recirculation damper failed closed on August 28 CR558542, TDAFW Pump following full flow test on September 15 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.
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.
Unit 2 RBCCW Outlet Valve Stroke and Timing Test following the drop test and addition of actuator oil on September 9 Unit 3 Auxiliary Feedwater Pump 3FWA*P2 Operational Readiness Test following replacement of the failed K1 relay and associated power supply on July 16 Station Blackout (SBO) Diesel following maintenance overhaul on July 23 TDAFW pump full flow test following governor replacement on September 13
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 structures, systems, and components 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 2610BS, TDAFW Pump Full Flow Test in Mode 3 on July 27 SP 2612A, A SW Pump and Facility 1 Discharge Check Valve in-service test on August 8 Unit 3 SP 3646A.1, A EDG Start from the Emergency Generator Loading Sequencer on July 8 SP 3622.3, Auxiliary Feedwater Pump 3FWA*P2 Operational Readiness Test on July 15 SP 3670.4-015, Quarterly SBO preventive maintenance on July 23 SP 3601F.5-007/008, Quarterly PORV Block Valve Stroke Testing change of In-service Testing frequency via relief request and Surveillance Testing frequency via surveillance frequency control program, on September 9 - 11 SP 3622.3, Auxiliary Feedwater Pump 3FWA*P2 Operational Readiness Test on September 29
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA1 Performance Indicator Verification
.1 Mitigating Systems Performance Index (10 samples)
a. Inspection Scope
The inspectors reviewed Dominions submittal of the Mitigating Systems Performance Index for the following systems for the period of July 1, 2013 through June 30, 2014:
Unit 2 Emergency AC System (EDGs) on September 29 High Pressure Injection System on September 8 Heat Removal System (Auxiliary Feedwater System) on September 8 Residual Heat Removal System on September 8 Cooling Water Systems on September 8 Unit 3 Emergency AC System (EDGs) on September 23 High Pressure Injection System on September 23 Heat Removal System (Auxiliary Feedwater System) on September 25 Residual Heat Removal System on September 23 Cooling Water Systems on September 23 To determine the accuracy of the performance indicator data reported during those periods, the inspectors used definitions and guidance contained in Nuclear Energy Institute Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7. The inspectors also reviewed Dominions operator narrative logs, CRs, 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 Dominion entered issues into their 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 and periodically attended CR screening meetings.
b. Findings
No findings were identified.
.2 Annual Sample: Unit 3 Reactor Plant Closed Cooling Water (RPCCW) Heat Exchanger
Tube Deterioration
a. Inspection Scope
The inspectors performed an in-depth review of Dominions apparent cause analysis and corrective actions associated with CR 553047, MP-3 Coating Damage in Inlet/Outlet End Channel Head over gasket area of 3CCP*E1A. Specifically, the A and B RPCCW heat exchangers, 3CCP*E1A/B, have experienced multiple tube leaks over a period of several years.
The inspectors assessed Dominions problem identification threshold, cause analyses, extent of condition reviews, compensatory actions, and the prioritization and timeliness of Dominions corrective actions to determine whether Dominion 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 Dominions 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.
The RPCCW heat exchangers have experienced tube leaks for several years. These leaks have resulted in several unplanned entries into TS 3.7.3 action statement which provides 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to isolate or repair the leak. The RPCCW system is currently in an A(1) status for the maintenance rule and the heat exchangers are scheduled for replacement in refueling outages 3RFO17, 18, and 19.
Although the number of plugged tubes in each heat exchanger is below 115 (the current design limit), the number of plugged tubes added to the number of significantly damaged tubes which may require plugging in the near future exceeds the limit of allowable plugged tubes. For the 3CCP*E1A heat exchanger there are 117 tubes and for 3CCP*E1B heat exchanger there are 180 tubes that are either plugged or significantly degraded. If left unmitigated, the current rate of degradation may exceed the tube plugging limit prior to the scheduled heat exchanger replacement.
The inspectors noted that several proposed corrective actions were being pursued.
CR 557017 directed preparation of work orders to implement a bridging strategy to coat the tube internals with a Plastocor epoxy for the first pass tubes of all three heat exchangers, 3CCP*E1A/B/C. This coating is designed to reduce the flow erosion rate and extend the life of the tubes until they are replaced.
.3 Annual Sample: Unit 2 Group 1 Pressurizer Proportional Heaters
a. Inspection Scope
The inspectors reviewed root cause evaluation 001114, associated with CR 538495, Entry into 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> shutdown TSAS [technical specification action statement]. On January 30, 2014, Unit 2 entered a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> shutdown action statement due to an unplanned loss of the Group 1 pressurizer proportional heaters concurrent with a planned maintenance outage on the B EDG. Dominion determined the root cause of the event was the continued failure of pressurizer heaters due to manufacturing defects associated with replacement heaters and determined this was a repeat failure because corrective actions to prevent recurrence (CAPRs) from a previous event in 2009 were not complete.
The inspectors assessed Dominions problem identification threshold, cause analyses, extent of condition reviews, compensatory actions, and the prioritization and timeliness of Dominions corrective actions to determine whether Dominion 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 Dominions CAP and 10 CFR 50, Appendix B.
b. Findings and Observations
No findings were identified.
In March 2009, Dominion completed a root cause analysis on a series of pressurizer heater and/or heater circuit failures that happened from 2007 - 2009, which determined that the root cause was fabrication deficiencies during the heater manufacturing process.
CAPRs for this root cause included:
- (1) design engineering to determine manufacturing process changes and/or assessment of alternate heaters;
- (2) determination of appropriate replacement interval for heaters; and
- (3) development of control scheme to increase heater longevity. CAPR 1 was closed because Dominion determined the heater design had more impact than the manufacturing process. CAPR 2 was closed with no action taken. CAPR 3 was closed to the Request for Engineering Assistance (REA) process, with no follow on assignment. According to the CAP process at the time, the CAPR should have directed a follow on assignment for an REA and should have remained open until the REA was complete. This REA was later cancelled by the plant health committee.
For the January 2014 event, Dominion developed one CAPR (CAPR 000982), to evaluate and determine the optimum solution for the Unit 2 pressurizer heater repeat failures. According to PI-AA-300, Cause Evaluation, Revision 7, CAPR is defined as actions designed to prevent recurrence of the root cause. The inspectors determined that CAPR 000982 as stated was not sufficient on its own to prevent recurrence, as it did not actually change anything related to the pressurizer heaters. However, this CAPR was closed on August 25, with an assignment to engineering to develop and present an REA for a new pressurizer heater design. Millstone Plant Health Working Group approved REA MP-2014-055 for scoping on August 11. The REA contains a reference to the CAPR, which acts as a safeguard to prevent inadvertent REA closure without an appropriate level of oversight. Completion and installation of the new heater design is not currently scheduled until 2RFO24 (2017), although there is a standing order for operators to monitor for a failed heater element as a short term corrective action. The inspectors noted that the REA creation completes the CAPR requirements as stated; however, at the close of the inspection period, there was nothing in the CAP driving the actual replacement of the heaters. The inspectors documented a licensee-identified corrective action violation for this issue in Section 4OA7 of this report. The inspectors noted that there are many steps in the REA process (scoping, funding, scheduling) to go until full restoration is complete.
4OA3 Follow-Up of Events and Notices of Enforcement Discretion
.1 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 Dominion made appropriate emergency classification assessments and properly reported the event in accordance with 10 CFR Parts 50.72 and 50.73. The inspectors reviewed Dominions follow-up actions related to the events to assure that Dominion implemented appropriate corrective actions commensurate with their safety significance.
Unit 2 TDAFW Pump In-service Test Failure on July 23 On July 23, Dominion entered the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Limiting Condition for Operation, TS 3.7.1.2, to perform scheduled in-service test surveillances. Following performance of SP 2610BO, TDAFW Tests, Operating, the TDAFW failed to meet the acceptance criteria for minimum recirculation flow. Dominion could not find a definitive cause for the test failure within the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed outage time and shut the plant down as required by the TS on July 26. On July 27, in Mode 3, Dominion performed a full flow TDAFW test in accordance with SP 2610BS, TDAFW Tests, Shutdown, with satisfactory results, which indicated the cause of the initial test failure was limited to the recirculation line. Dominion found a small piece of debris in the chambers of the recirculation line flow orifice and successfully ran the operational test on July 28 before returning the unit online.
Unit 3 TDAFW Pump Failure to Start on July 15 At 3:58 AM on July 14, Dominion entered the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Limiting Condition for Operation, TS 3.7.1.2, to perform maintenance activities associated with the TDAFW pump that consisted of a lube oil pressure calibration, a discharge pressure calibration, centering two pins located in the overspeed trip latch mechanism, and a limit switch calibration on the AOV-31A Steam Admission valve. At 5:25 AM on July 15, 2014, when attempting to start the TDAFW pump, the pump failed to start and come up to rated speed. Dominion performed subsequent troubleshooting and concluded that the K1 under-speed relay and associated power supply was not functioning properly and they were both replaced. At 8:00 PM on July 16, 2014, Dominion successfully ran a TDAFW surveillance run and post-maintenance test. Following completion of the surveillance, while removing the test equipment, the technician accidently shorted the test leads and blew two fuses in the speed controller circuit. Following completion of the fuse replacement and circuit testing, the TDAFW was declared operable at 2:17 AM on July 17, 2014.
TDAFW Pump Failure to Start on September 10 On September 10, the Unit 3 TDAFW pump failed to start during routine surveillance testing. Due to the similarities with the July events and the NRCs continued concern with the reliability of the TDAFW, the NRC decided to launch a Special Inspection Team to review the events and Dominions troubleshooting activities. The Special Inspection Team began onsite activities on September 15 to review the adequacy and completeness of testing on the pump and causal evaluations of the problems.
The results of the Special Inspection will be discussed in a report expected to be issued within 45 days after the completion of the inspection.
b. Findings
No findings were identified.
As stated above, the Special Inspection Team is ongoing and may identify further performance deficiencies which will be evaluated and documented in future inspection reports.
.2 (Closed) Licensee Event Report (LER) 05000336/2014-006-00: Millstone Power Station
Dual Unit Reactor Trip on Loss of Offsite Power At 7:01 AM, on May 25, 2014, a dual-unit reactor trip occurred at Millstone. Prior to the event, the station had one offsite line out-of-service (Line 371) for maintenance. A suspected ground fault on the grid in the Northeast Utilities Card substation caused the loss of offsite line 383. Line 310 tripped on instantaneous ground over current which was unexpected. The final line (Line 348) tripped on over current when both units attempted to feed the full power output of both Millstone units through the single remaining line (Line 348). All onsite EDGs started and powered their respective safety busses. Dominion declared a Notice of Unusual Event (NOUE) for both units at 7:15 AM due to a loss of offsite power for greater than 15 minutes. Offsite power was restored to at least one safety bus at each unit by approximately 10:30 AM and fully restored at 12:56 PM on May 25, 2014. Dominion exited the NOUE at 2:14 PM on May 25, 2014.
The NRC completed a Special Inspection in response to this plant event on July 15 and the enforcement aspects of this event are discussed in the Special Inspection report 05000336/2014011 and 05000423/2014011 (ML14240A006). The inspectors did not identify any new issues during the review of the LER. This LER is closed.
.3 (Closed) LER 05000423/2014-001-00: Limiting Condition for Operation Exceeded Upon
Approval of Enforcement Discretion and
.4 (Closed) LER 05000423/2014-003-00: TDAFW Pump Operability Impacted by Incorrect
Bearing On January 26, Dominion requested and received a Notice of Enforcement Discretion (NOED) from the requirements of TS 3.7.1.2, Action C, to complete restoration and post-maintenance testing of the TDAFW following a failed surveillance test. Following the successful test and after declaring the TDAFW system operable, Dominion determined that the installed cam follower bearing, that rolls in the cam plate slot, was an inappropriate part. Specifically, the installed bearing lacked an aluminum bronze insert that provided inherent lubricity. On February 3, Dominion took the TDAFW pump out of service, replaced the cam follower bearing with the correct part, successfully completed post-maintenance testing, and declared TDAFW operable.
The NRC completed a Special Inspection in response to the TDAFW system failure and the enforcement aspects are discussed in the Special Inspection Report 05000423/2014008 (ML14240A051). The inspectors did not identify any new issues during the review of the LERs. These LERs are closed.
.5 (Closed) LER 05000423/2013-008-00: Loss of Licensed Radioactive Material, Trijicon
Rifle Scopes On December 11, 2013, Dominion reported the theft of two security rifle scopes to the NRC in accordance with 10 CFR 20.2201(a)(ii). These rifle scopes are similar to ones commonly sold for general use by the public without additional regulatory controls due to the low level of radioactivity contained within (57.766 milli-Curies and 60.528 milli-Curies of tritium for each scope). Because Millstone is an NRC licensee, Dominion is subject to additional regulatory requirements related to the reporting of devices containing licensed material. Dominion worked with the Waterford, Connecticut Police Department to conduct an investigation and recovered one of the scopes in question. The inspectors did not identify any new issues during the review of the LER. This LER is closed.
.6 (Closed) LER 05000336/2014-005-00: Train A Containment Spray Inoperable Due to
Gas Voids On May 17, while returning Unit 2 to power following a refueling outage, Dominion discovered the presence of gas voids in the A containment spray system, which rendered the system inoperable. The gas was introduced into the system during maintenance work earlier in the refueling outage, but was not detected until Dominion completed surveillance testing on May 17. Dominion vented the system and restored the containment spray system to operable on May 17, 88 hours0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br /> after entering TS 3.6.2.1. The enforcement aspects of this issue are discussed in Section 4OA7. The inspectors did not identify any new issues during the review of the LER. This LER is closed.
.7 (Closed) LER 05000336/2014-001-00): Completion of Plant Shutdown Required by
Technical Specifications On January 30, 2014, Unit 2 entered a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> shutdown action statement due to an unplanned loss of the Group 1 pressurizer proportional heaters concurrent with a planned maintenance outage on the B EDG. Dominion determined the root cause of the event was the continued failure of pressurizer heaters due to manufacturing defects associated with replacement heaters and determined this was a repeat failure because CAPRs from a previous event in 2009 were not complete. The inspectors reviewed this issue as a Problem Identification and Resolution sample which is documented in Section 4OA2. The enforcement aspects of this issue are discussed in Section 4OA7. The inspectors did not identify any new issues during the review of the LER. This LER is closed.
4OA6 Meetings, Including Exit
On October 7, the inspectors presented the inspection results to Mr. Daniel G. Stoddard, Senior Vice President for Nuclear Operations, Mr. 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.
4OA7 Licensee-Identified Violations
The following violations of very low safety significance (Green) were identified by Dominion and are violations of NRC requirements which meet the criteria of the NRC Enforcement Policy for being dispositioned as non-cited violations.
TS 3.6.2.1, Containment Spray and Cooling Systems, requires two containment spray trains and two containment cooling trains to be operable in Modes 1, 2, and 3.
If one containment spray train is inoperable, the TS required action is to restore the inoperable train within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in Hot Standby within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. Contrary to the above, at 7:33 PM on May 16, Dominion exceeded the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed outage time for the A containment spray train, due to the delayed completion of the gas void detection surveillance test. In addition, TS 3.0.4 prohibits entry into an Operational Mode without all requisite limiting conditions of operation met. Contrary to the above, at 7:33 PM on May 13, Unit 2 entered Mode 3 with pressure greater than 1750 psia and an inoperable A containment spray train. Dominion entered the issue into the CAP as CR 549280. The inspectors determined that this finding was of very low safety significance using IMC 0609, Appendix A, because the period of unavailability was of short duration (approximately 88 hours0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br />) and occurred during Mode 3. The B train of containment spray remained unaffected by the voids found in the A train.
10 CFR 50, Appendix B, Criterion XVI, states, in part, that measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected. Contrary to the above, for the January 30 Unit 2 pressurizer heater failure, Dominion determined the root cause of the event was the continued failure of pressurizer heaters due to manufacturing defects associated with replacement heaters and determined this was a repeat failure because CAPRs from a previous event in 2009 were not complete. Dominion entered the issue into the CAP as CR 538495. The inspectors determined that this finding was of very low safety significance using IMC 0609, Appendix A, because the finding did not cause a reactor trip and the loss of mitigation equipment relied upon to transition the plant from the onset of the trip to a stable shutdown condition.
ATTACHMENT:
SUPPLEMENTARY INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
M. Adams Plant Manager
- L. Armstrong Director, Nuclear Station Safety & Licensing
G. Auria Nuclear Chemistry Supervisor
- B. Bartron Supervisor, Licensing
- P. Baumann Manager, Nuclear Protection Services
J. Beaudoin Unit 3 Control Operator
T. Berger Unit 3 Shift Manager
- R. Borchert Consulting Engineer, Reactor Engineering
E. Brodeur Unit 3 Shift Manager
J. Chadourne Unit 2 IST Engineer
C. Chapin Assistant Operations Manager Unit 2
W. Chesnutt Unit 2 Supervisor Nuclear Shift Operations
C. Chatman Unit 3 Shift Manager
- W. Chestnut Supervisor, Nuclear Shift Operations Unit 2
T. Cleary Licensing Engineer
J. Claire Unit 2 Unit Supervisor
G. Closius Licensing Engineer
J. Cote Unit 3 Control Operator
- M. Cote Senior Instructor, Nuclear Operations
- L. Crone Supervisor, Nuclear Chemistry
- J. Curling Manager, Protection Services
D. Daugherty RBCCW System Engineer
S. DoBoe Unit 3 Shift Manager
J. Dorosky Health Physicist III
E. Dundon Nuclear Engineer III
B. Ferguson Unit 2 Shift Manager
- M. Finnegan Supervisor, Health Physics, ISFSI
J. Foster Unit 3 Plant Equipment Operator
J. Gardner Nuclear Engineer III
A. Gharakhanian Nuclear Engineer III
M. Goolsbey Nuclear Operations Manager
- W. Gorman Supervisor, Instrumentation & Control
J. Grogan Supervisor Nuclear Training
C. Houska I&C Technician
J. Keith Unit 3 Senior Reactor Operator
T. Killalea Engineer
G. Knight Unit 3 Plant Equipment Operator
- J. Laine Manager, Radiation Protection/Chemistry
- J. Langdon Manager, Nuclear Oversight
L. Lash Unit 3 Control Operator
M. Legg Nuclear Engineer III
- G. Marshall Manager, Outage and Planning
- R. McDonald Senior Instructor, Nuclear Operations
M. OConner Nuclear Specialist Station Support
- J. Palmer Manager, Training
K. Perkins Unit 3 Shift Technical Advisor
D. Reed Unit 3 Shift Manager
- J. Rigatti Manager, Nuclear Site Engineering
M. Roche Senior Nuclear Chemistry Technician
D. Rowe Unit 3 Shift Manager
J. Rogers Senior Instructor Nuclear Operations
P. Russell Unit 3 Shift Manager
R. Sadler Unit 3 Unit Supervisor
- L. Salyards Licensing, Nuclear Technology Specialist
S. Scace Site Vice President
M. Scott Unit 3 Shift Manager
P. Scott Unit 3 Shift Manager
H. Searle Unit 2 Control Operator / Senior Instructor
- S. Stanley Director, Nuclear Engineering
E. Smith System Engineer
- S. Smith Manager, Nuclear Operations
J. Spalter Unit 3 Supervisor
T. Spakowski Unit 2 Control Operator / Senior Instructor
J. Stoddard Supervisor Nuclear Shift Operations Unit 3
- S. Turowski Supervisor, Health Physics Technical Services
K. Truesdale Senior Instructor Nuclear Operations
- C. Vournazos IT Specialist, Meteorological Data
J. Wasylik Unit 2 Shift Manager
K. Woods Unit 3 Control Operator
- J. Young Senior Instructor, Nuclear Operations
LIST OF ITEMS OPENED, CLOSED, DISCUSSED, AND UPDATED
Closed
- 05000336/2014-006-00 LER Millstone Power Station Dual Unit Reactor Trip on Loss of Offsite Power (section 4OA3)
- 05000123/2014-001-00 LER Limiting Condition for Operation Exceeded Upon Approval of Enforcement Discretion (section 4OA3)
- 05000423/2014-003-00 LER Turbine Driven Auxiliary Feedwater (TDAFW) Pump Operability Impacted by Incorrect Bearing (section 4OA3)
- 05000423/2013-008-00 LER Loss of Licensed Radioactive Material, Trijicon Rifle Scopes (section 4OA3)
- 05000336/2014-005-00 LER Train A Containment Spray Inoperable Due to Gas Voids (section 4OA3)
- 05000336/2014-001-00 LER Completion of Plant Shutdown Required by Technical Specifications (section 4OA3)