IR 05000528/2017004
| ML18030A678 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 01/30/2018 |
| From: | Geoffrey Miller NRC/RGN-IV/DRP/RPB-D |
| To: | Bement R Arizona Public Service Co |
| Miller G | |
| References | |
| IR 2017004 | |
| Download: ML18030A678 (45) | |
Text
nuary 30, 2018
SUBJECT:
PALO VERDE NUCLEAR GENERATING STATION - NRC INTEGRATED INSPECTION REPORT 05000528/2017004, 05000529/2017004, AND 05000530/2017004
Dear Mr. Bement:
On December 31, 2017, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Palo Verde Nuclear Generating Station Units 1, 2, and 3. On January 11, 2018, the NRC inspectors discussed the results of this inspection with Ms. Maria Lacal and other members of your staff. The results of this inspection are documented in the enclosed report.
NRC inspectors documented one finding of very low safety significance (Green) in this report.
This finding involved a violation of NRC requirements. The NRC is treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2.a of the Enforcement Policy.
If you contest the violation or significance of the NCV, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region IV; the Director, Office of Enforcement; and the NRC resident inspector at Palo Verde. 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 at the NRC Public Document Room in accordance with 10 CFR 2.390, Public Inspections, Exemptions, Requests for Withholding.
Sincerely,
/RA/
Geoffrey B. Miller, Branch Chief Project Branch D Division of Reactor Projects Docket Nos. 50-528, 50-529, 50-530 License Nos. NPF-41, NPF-51, NPF-74 Enclosure:
Inspection Report 05000528/2017004, 05000529/2017004, 05000530/2017004 w/ Attachments:
1. Supplemental Information 2. Information Request for the Radiation Safety Team Inspection 3. Information Request for the Baseline Inservice Inspection
U.S. NUCLEAR REGULATORY COMMISSION
REGION IV
Docket: 05000528, 05000529, 05000530 License: NPF-41, NPF-51, NPF-74 Report: 05000528/2017004, 05000529/2017004, and 05000530/2017004 Licensee: Arizona Public Service Company Facility: Palo Verde Nuclear Generating Station Location: 5801 South Wintersburg Road Tonopah, AZ 85354 Dates: October 1 through December 31, 2017 Inspectors: C. Peabody, Senior Resident Inspector D. Reinert, PhD, Resident Inspector D. You, Resident Inspector I. Anchondo, Reactor Inspector L. Carson, Senior Health Physicist N. Green, PhD, Health Physicist S. Hedger, Emergency Preparedness Inspector B. Larson, Senior Operations Engineer Approved Geoffrey B. Miller By: Chief, Project Branch D Division of Reactor Projects Enclosure
SUMMARY
IR 05000528, 05000529, 05000530/2017004, 10/1/2017 - 12/31/2017; PALO VERDE
NUCLEAR GENERATING STATION INTEGRATED INSPECTION REPORT; Post-Maintenance Testing.
The inspection activities described in this report were performed between October 1 and December 31, 2017, by the resident inspectors at Palo Verde Nuclear Generating Station and inspectors from the NRCs Region IV office. One finding of very low safety significance (Green)is documented in this report. The significance of inspection findings is indicated by their color (i.e., Green, greater than Green, White, Yellow, or Red), determined using Inspection Manual Chapter 0609, Significance Determination Process, dated April 29, 2015. Their cross-cutting aspects are determined using Inspection Manual Chapter 0310, Aspects within the Cross-Cutting Areas, dated December 4, 2014. Violations of NRC requirements are dispositioned in accordance with the NRC Enforcement Policy. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, dated July 2016.
Cornerstone: Mitigating Systems
- Green.
The inspectors reviewed a self-revealed, non-cited violation of Technical Specification 5.4.1.a Procedures, for the failure to incorporate vendor service recommendations into the preventive maintenance program. As a result of not incorporating those recommendations, a Class 1E 4kV circuit breaker failed, rendering the Unit 2 spray pond pump B and diesel generator B inoperable. The licensee entered this condition into their corrective action program as Condition Report 17-13171. The licensee will take corrective action to replace all affected Class 1E circuit breaker components installed throughout the station. The licensee will also take corrective actions to address extent of condition by performing a Quality Assurance self-assessment of vendor recommendations reviewed during the 1990s to ensure with reasonable confidence that similar recommendations are not inadvertently being ignored.
Failure to implement or address a vendor recommendation in the preventive maintenance program is a performance deficiency. Specifically, in 1996 the licensee failed to act on General Electric Service Advisory Letter 352.1, recommendation #4, to replace the drive pawl pivot pin assembly to improve reliability. This was contrary to station procedure 30DP-9MP08, Preventive Maintenance Basis Development, Revision 5, Step A.1.10. This performance deficiency is more than minor and, therefore, a finding because it affected the equipment performance attribute of the Mitigating Systems cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, on September 19, 2017, the welded drive pawl pivot pin assembly failed on the Unit 2 spray pond pump B circuit breaker causing an inoperability and unavailability of the spray pond pump B and supported systems; as well as the inoperability of the associated diesel generator. The inspectors performed a significance determination using Inspection Manual Chapter 0609, Appendix A, Exhibit 2, Mitigating Systems Screening Questions, and determined that the finding was of very low safety significance (Green) because the finding did not represent an actual loss of function of a single train for greater than its technical specification allowed outage time. The inspectors concluded that no cross-cutting aspects should be applicable because the performance deficiency is not indicative of current licensee performance. (Section 1R19)
PLANT STATUS
Unit 1 operated at full power for the inspection period with a planned refueling outage from October 7, 2017, through November 6, 2017.
Units 2 and 3 operated at full power for the entire inspection period.
REPORT DETAILS
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
1R04 Equipment Alignment
Partial Walk-Down
a. Inspection Scope
The inspectors performed partial system walk-downs of the following risk-significant systems:
- November 17, 2017, Unit 3 480 volt essential electric system A
- December 15, 2017, Unit 3 control building ventilation for the Class 1E batteries and the DC equipment rooms
- December 19, 2017, Unit 1 spent fuel pool cooling system The inspectors reviewed the licensees procedures and system design information to determine the correct lineup for the systems. They visually verified that critical portions of the systems were correctly aligned for the existing plant configuration.
These activities constituted three partial system walk-down samples as defined in Inspection Procedure 71111.04.
b. Findings
No findings were identified.
1R05 Fire Protection
Quarterly Inspection
a. Inspection Scope
The inspectors evaluated the licensees fire protection program for operational status and material condition. The inspectors focused their inspection on five plant areas important to safety:
- October 16, 2017, Unit 1 condensate storage tank area
- October 25, 2017, Unit 2 lower cable spreading room, Fire Zone 14
- November 8, 2017, Unit 3 remote shutdown panel B room, Fire Zone 10B
- December 19, 2017, Unit 1 Class 1E 4kV switchgear B room, Fire Zone 5B
- December 28, 2017, Unit 2 Class 1E battery B and D rooms, Fire Zone 8B and 9B For each area, the inspectors evaluated the fire plan against defined hazards and defense-in-depth features in the licensees fire protection program. The inspectors evaluated control of transient combustibles and ignition sources, fire detection and suppression systems, manual firefighting equipment and capability, passive fire protection features, and compensatory measures for degraded conditions.
These activities constituted five quarterly inspection samples, as defined in Inspection Procedure 71111.05.
b. Findings
No findings were identified.
1R08 Inservice Inspection Activities
.1 Non-destructive Examination Activities and Welding Activities
a. Inspection Scope
The inspectors directly observed the following nondestructive examinations:
SYSTEM COMPONENT/WELD IDENTIFICATION EXAMINATION TYPE Steam Generator SG-1 Nozzle-to-Vessel Ultrasonic Weld 3-101 Report 17-UTE-1046 Steam Generator SG-1 Cold Leg Inner Radius Ultrasonic Weld 3-102 Report 17-UTE-1045 Steam Generator SG-to-Nozzle Magnetic Particle Weld 41-110 Report 17-MT-1006 Feedwater Pipe-to-Pipe Magnetic Particle Weld 57-3 Report 17-MT-1007 Steam Generator SG-1 Nozzle-to-Vessel Ultrasonic Weld 3-102 Report 17-UTE-1047 The inspectors reviewed records for the following nondestructive examinations:
SYSTEM COMPONENT/WELD IDENTIFICATION EXAMINATION TYPE Steam Generator SG-to-Nozzle Ultrasonic Weld 41-110 Report 17-UTE-1042 Feedwater Pipe-to-Pipe Ultrasonic Weld 57-3 Report 17-UTE-1053 Reactor Vessel Bottom Head Area Weld, Cladding Visual (VT-3)
During the review and observation of each examination, the inspectors observed whether activities were performed in accordance with the American Society of Mechanical Engineers (ASME) Code requirements and applicable procedures. The inspectors reviewed two indications that were previously examined, and observed whether the licensee evaluated and accepted the indications in accordance with the ASME Code and/or an NRC approved alternative. The inspectors also reviewed the qualifications of all nondestructive examination technicians performing the inspections to determine whether they were current.
During Refueling Outage 1R20, a visual inspection (VT-3), as part of the 10-year inservice inspection of the reactor vessel, identified an indication adjacent to the 180-degree flow baffle support pad. The indication was determined to be 0.7-inches x 0.8-inches x 0.20-inches in depth. The inspectors verified that the indication was acceptable by ASME Code requirements. The licensees corrosion analysis determined, that within a 15 year interval, the affected area will degrade an additional 0.2765 inches. This is equivalent to 4.25 percent degradation of the wall thickness at the next inservice inspection. Therefore, the requirements of IWB-3520.2(d) of Section XI of the ASME Code are expected to be satisfied prior to the next required inspection. The inspectors concluded that the postulated corrosion rates are conservative and find it appropriate for the licensee to perform the next required inspection on a normally scheduled 10-year inservice inspection with adequate assurance that the structural integrity of the reactor vessel will remain intact.
b. Findings
No findings were identified.
.2 Vessel Upper Head Penetration Inspection Activities
a. Inspection Scope
The inspectors reviewed the results of the licensees bare metal visual inspection of the Reactor Vessel Upper Head Penetrations to determine whether the licensee identified any evidence of boric acid challenging the structural integrity of the reactor head components and attachments. The inspectors also verified that the required inspection coverage was achieved and limitations were properly recorded. The inspectors reviewed whether the personnel performing the inspection were certified examiners to their respective nondestructive examination method. During the examination, the licensee identified 14 Control Element Drive Mechanism nozzle penetrations that had been affected by leakage coming from a vent valve above the reactor vessel head at the start of the previous operating cycle. Discounting the apparent source of the leakage, the requirements of ASME Code Case 729-4, Alternative Examination Requirements for PWR Reactor Vessel Upper Heads with Nozzles Having Pressure-Retaining Partial-Penetration WeldsSection XI, Division 1, require the classification of the physical condition of the affected nozzle penetrations as containing a relevant condition.
Specifically, Code Case 729-4 requires further interrogation of the relevant condition to verify that the condition is not indicative of possible nozzle leakage. The licensee proceeded to clean the affected nozzle penetrations without any further actions. The inspectors identified that the actions taken by the licensee were not in compliance with the requirements of ASME Code Case N-729-4. Consequently, by letter dated October 26, 2017, the licensee submitted Relief Request RR-57, Request for Alternative to American Society of Mechanical Engineers Code Case N-729-4 for Replacement Reactor Vessel Closure Head Penetration Nozzles. The NRC granted verbal authorization on November 1, 2017, concluding that the licensees proposed alternative to perform a bare metal visual examination of 14 nozzles penetrations in accordance with ASME Code Case N-729-4, during the operating cycle 21, will provide reasonable assurance of the structural integrity of the reactor vessel closure head until the next scheduled volumetric or visual examination. At the time of the inspection, the NRC had not yet written a safety evaluation. The licensee documented the condition on the reactor vessel head in Condition Report 2017-14723.
b. Findings
No findings were identified.
.3 Boric Acid Corrosion Control Inspection Activities
a. Inspection Scope
The inspectors reviewed the licensees implementation of its boric acid corrosion control program for monitoring degradation of those systems that could be adversely affected by boric acid corrosion. The inspectors reviewed the documentation associated with the licensees boric acid corrosion control walk-down as specified in procedures 70TI-9ZC01, Boric Acid Walkdown Leak Detection, Revision 19, and 73DP-9ZC01, Boric Acid Corrosion Control Program, Revision 7. The inspectors reviewed whether the visual inspections emphasized locations where boric acid leaks could cause degradation of safety significant components, and whether engineering evaluation used corrosion rates applicable to the affected components and properly assessed the effects of corrosion-induced wastage on structural or pressure boundary integrity. The inspectors observed whether corrective actions taken were consistent with the ASME Code, and 10 CFR Part 50, Appendix B requirements.
b. Findings
No findings were identified.
.4 Steam Generator Tube Inspection Activities
a. Inspection Scope
No steam generator tube inspection activities were scheduled for Palo Verde, Unit 1, Refueling Outage 1R20.
b. Findings
No findings were identified.
.5 Identification and Resolution of Problems
a. Inspection Scope
The inspectors reviewed 18 condition reports which dealt with inservice inspection activities and found the corrective actions for inservice inspection issues were appropriate. From this review the inspectors concluded that the licensee has an appropriate threshold for entering inservice inspection issues into the corrective action program and has procedures that direct a root cause evaluation when necessary. The licensee also has an effective program for applying industry inservice inspection operating experience. Specific documents reviewed during this inspection are listed in the attachment.
b. Findings
No findings were identified.
These activities constituted completion of one inservice inspection sample, as defined in Inspection Procedure 71111.08
1R11 Licensed Operator Requalification Program and Licensed Operator Performance
.1 Review of Licensed Operator Requalification
a. Inspection Scope
On November 14, 2017, the inspectors observed a portion of an annual requalification test for licensed operators. The inspectors assessed the performance of the operators and the evaluators critique of their performance. The inspectors also assessed and the modeling and performance of the simulator during the requalification activities.
These activities constituted completion of one quarterly licensed operator requalification program sample, as defined in Inspection Procedure 71111.11.
b. Findings
No findings were identified.
.2 Review of Licensed Operator Performance
a. Inspection Scope
On October 6, 2017, the inspectors observed the performance of on-shift licensed operators in the plants main control room. At the time of the observations, the plant was in a period of heightened activity due to a planned reactor shutdown for a refueling outage. The inspectors observed the operators control of reactivity during the scheduled reactor shutdown.
In addition, the inspectors assessed the operators adherence to plant procedures, including 40DP-9OP02, Conduct of Operations, Revision 72, and other operations department policies.
These activities constituted completion of one quarterly licensed operator performance sample, as defined in Inspection Procedure 71111.11.
b. Findings
No findings were identified.
.3 Annual Review of Requalification Examination Results
a. Inspection Scope
The inspector conducted an in-office review of the annual requalification training program to determine the results of this program.
On December 22, 2017, the licensee informed the inspector of the following Palo Verde Nuclear Generating Station annual operating test results:
- 21 of 21 crews passed the simulator scenario portion of the operating test
- 107 of 107 licensed operators passed the simulator scenario portion of the operating test
- 105 of 107 licensed operators passed the job performance measure portion of the operating test The two operators that failed the job performance measure portion of the operating test were remediated and successfully passed a retake operating test prior to returning to shift.
The inspector completed one inspection sample of the annual licensed operator requalification program.
b. Findings
No findings were identified.
1R12 Maintenance Effectiveness
Quality Control
a. Inspection Scope
On November 29, 2017, the inspectors reviewed the licensees quality control activities through a review of parts installed in fire dampers that were purchased as commercial-grade parts but were dedicated prior to installation in a quality-grade application.
These activities constituted completion of one quality control sample, as defined in Inspection Procedure 71111.12.
b. Findings
No findings were identified.
1R13 Maintenance Risk Assessments and Emergent Work Control
a. Inspection Scope
The inspectors reviewed two risk assessments performed by the licensee prior to changes in plant configuration and the risk management actions taken by the licensee in response to elevated risk:
- October 11, 2017, Unit 1 reactor coolant system reduced inventory volume to remove reactor vessel head for refueling
- October 20, 2017, Unit 1 reactor coolant pump 2B motor heavy lift The inspectors verified that these risk assessments were performed timely and in accordance with the requirements of 10 CFR 50.65 (the Maintenance Rule) and plant procedures. The inspectors reviewed the accuracy and completeness of the licensees risk assessments and verified that the licensee implemented appropriate risk management actions based on the result of the assessments.
The inspectors also observed portions of two emergent work activities that had the potential to affect the functional capability of mitigating systems:
- October 3, 2017, Unit 1 train A diesel generator trip on high jacket water temperature
- November 21, 2017, Unit 2 auxiliary feedwater pump B motor circuit breaker replacement The inspectors verified that the licensee appropriately developed and followed a work plan for these activities. The inspectors verified that the licensee took precautions to minimize the impact of the work activities on unaffected structures, systems, and components (SSCs).
These activities constituted completion of four maintenance risk assessments and emergent work control inspection samples, as defined in Inspection Procedure 71111.13.
b. Findings
No findings were identified.
1R15 Operability Determinations and Functionality Assessments
a. Inspection Scope
The inspectors reviewed four operability determinations that the licensee performed for degraded or nonconforming structures, systems, or components (SSCs):
- October 3, 2017 operability determination of Unit 1 diesel generator A following high jacket water temperature trip during surveillance testing
- October 12, 2017, operability determination of Unit 3 train A spray pond pump following an inservice test
- November 3, 2017, operability determination of Unit 1 reactor vessel stainless steel cladding degradation
- December 21, 2017, operability determination of Unit 1 high pressure safety injection pump A boric acid leakage from pump seals and mini-flow line drain The inspectors reviewed the timeliness and technical adequacy of the licensees evaluations. Where the licensee determined the degraded SSC to be operable, the inspectors verified that the licensees compensatory measures were appropriate to provide reasonable assurance of operability. The inspectors verified that the licensee had considered the effect of other degraded conditions on the operability of the degraded SSC.
These activities constituted completion of four operability and functionality review samples as defined in Inspection Procedure 71111.15.
b. Findings
No findings were identified.
1R19 Post-Maintenance Testing
a. Inspection Scope
The inspectors reviewed five post-maintenance testing activities that affected risk-significant structures, systems, or components (SSCs):
- October 4, 2017, Unit 2 Class 1E battery charger C following preventive maintenance
- October 17, 2017, Unit 1 Class 1E circuit breaker to load center 33 following breaker replacement to remove welded driving pall crank assembly
- October 17, 2017, Unit 1 Class 1E circuit breaker to load center 35 following breaker replacement to remove welded driving pall crank assembly
- October 18, 2017, Unit 1 Class 1E battery A discharge test following battery bank replacement
- October 24, 2017, Unit 1 low pressure safety injection pump A inservice test following motor replacement The inspectors reviewed licensing- and design-basis documents for the SSCs and the maintenance and post-maintenance test procedures. The inspectors observed the performance of the post-maintenance tests to verify that the licensee performed the tests in accordance with approved procedures, satisfied the established acceptance criteria, and restored the operability of the affected SSCs.
These activities constituted completion of five post-maintenance testing inspection samples as defined in Inspection Procedure 71111.19.
b. Findings
Failure to Incorporate Vendor Overhaul Recommendations for Class 1E Medium Voltage Circuit Breaker Preventive Maintenance Program
Introduction.
The inspectors reviewed a self-revealed, Green, non-cited violation of Technical Specification 5.4.1.a Procedures. for the failure to incorporate vendor service recommendations into the preventive maintenance program. As a result of not incorporating those recommendations, a Class 1E 4kV circuit breaker failed, rendering the Unit 2 spray pond pump B and diesel generator B inoperable.
Description.
On September 19, 2017, at 8:35 p.m., Unit 2 control room operators started spray pond pump B for routine pond water chemistry control and optimization. After the pump was started, operators received safety equipment inoperable status alarms for the Unit 2 spray pond pump B circuit breaker. An auxiliary operator responded to the equipment in the field and determined that the closing springs were discharged and, although the charging motor could be heard running, the springs were not charging. If the springs are not charged, the breaker cannot reclose as designed following a loss of offsite power. The licensee declared the affected spray pond pump B inoperable, which also made the associated diesel generator B inoperable for loss of cooling. The failed spray pond pump condition therefore rendered all train B safety equipment unable to respond during a loss of offsite power. The licensee swapped out the Class 1E 4kV GE Magneblast circuit breaker with a spare. The spray pond pump was tested to restore operability to all affected components at 9:27 a.m. on the morning of September 20, 2017. No applicable technical specification action statement completion times were exceeded.
Examination of the failed circuit breaker revealed that the cause of the failure was a mechanical failure of the drive pawl assembly. Specifically, a welded pin that held the assembly in place failed causing the assembly to fall to the bottom of the cabinet. On September 27, 2017, a group of engineers and electricians working on the corrective actions updated the inspectors on their preliminary findings. The licensee determined that the failure that occurred was applicable to recommendation #4 from GE Service Advisory Letter (SAL) 352.1, dated July 7, 1995. The recommendation was to replace the driving pawl crank assembly at the next overhaul opportunity to incorporate a revised driving pawl pivot pin assembly to improve reliability. Further licensee investigation determined that the basis for the recommendation was 10 CFR Part 21 Report #79015, submitted by the Golden Gate Switchboard Company in 1979. That report detailed a high cycle qualification testing failure of the same welded pin. In response to this event, in November 1979, GE redesigned the driving pawl crank assembly to a mechanical pin connection in order to improve reliability. During this time Palo Verde was procuring breakers for plant construction, which is why the plant had a combination of old and new style breakers. Although they redesigned the driving pawl assembly, GE did not recall the welded pin breakers already delivered, and did not otherwise communicate the vulnerability until the roll-up SAL 352.1 issued in July 1995. The licensee reviewed SAL 352.1 under Adverse Condition Report Disposition Request 9-6-Q583 and, amidst confusion, incorrectly determined SAL 352.1 was merely a roll up of many previous SALs already addressed in the corrective action program. The licensee did not specify a proper evaluation and disposition for recommendation #4. As a result, when the failed breaker was last overhauled in 2004, the welded driving pawl assembly was reused.
The inspectors determined that failure to incorporate vendor recommendations without analysis or basis is a violation of the preventive maintenance program. In 1995, station procedure 30DP-9MP08, Preventive Maintenance Basis Development, Revision 5, was in effect. Appendix A, Section 1, PM Basis Evaluation Logic and Approval Process -
Research for Recommendations and Requirements, Step A.1.10, requires the licensee to consider recommendations or requirements provided in other pertinent documents including vendor Technical Information Letters. This procedural requirement has not changed noticeably in the last 23 years. Current station procedure 30DP-9MP08, Preventive Maintenance Program, Revision 28, contains the same guidance in Appendix A, step A.2.10.
Analysis.
Failure to implement or otherwise address a vendor recommendation in the preventive maintenance program is a performance deficiency. Specifically, in 1996 the licensee failed to act on GE SAL 352.1, recommendation #4, to replace the drive pawl pivot pin assembly to improve reliability, contrary to station procedure 30DP-9MP08, Revision 5, Step A.1.10. This performance deficiency is more than minor and, therefore, a finding because it affected the equipment performance attribute of the Mitigating Systems cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences.
Specifically, on September 19, 2017, the welded drive pawl pivot pin assembly failed on the Unit 2 spray pond pump B circuit breaker causing an inoperability and unavailability of the spray pond pump B and supported systems; as well as the inoperability of the associated diesel generator. The inspectors performed a significance determination using Inspection Manual Chapter 0609, Appendix A, Exhibit 2, Mitigating Systems Screening Questions, and determined that the finding was of very low safety significance (Green) because the finding did not represent an actual loss of function of a single train for greater than its technical specification allowed outage time. The inspectors concluded that no cross-cutting aspects should be applicable because the performance deficiency is not indicative of current licensee performance.
Enforcement.
Technical Specification 5.4.1.a Procedures, requires, in part, that the licensee implement procedures recommended by Regulatory Guide 1.33, Revision 2.
Regulatory Guide 1.33, Appendix A, Section 9.b, recommends procedures for scheduling preventive maintenance of components that have a specified lifetime. The licensee satisfies these requirements, in part, through procedure 30DP-9MP08, Preventive Maintenance Basis Development, Revision 5. Procedure 30DP-9MP08, Step A.1.10, requires the licensee to consider recommendations or requirements provided in other pertinent documents such including vendor technical information letters. Contrary to the above, from October 23, 1996, through September 20, 2017, the licensee did not appropriately consider GE SAL 352.1, a pertinent document, recommendation #4 to replace the drive pawl pivot pin assembly. As a result, on September 19, 2017, a welded drive pawl pivot pin assembly failed causing the loss of Unit 2 spray pond pump train B and supported systems. The licensee entered this condition into their corrective action program as Condition Report 17-13171. The licensee will take corrective action to replace all 45 of the welded drive pawl pivot pin assemblies installed throughout the station. The licensee will also take corrective actions to address extent of condition by performing a Quality Assurance self-assessment of vendor recommendations reviewed during the 1990s to ensure with reasonable confidence that similar recommendations are not inadvertently being ignored. Because this finding is of very low safety significance (Green), and has been entered into the licensee corrective action program, it is being treated as a non-cited violation in accordance with Section 2.3.2.a of the NRC Enforcement Policy, NCV 05000529/2017004-01 Failure to Incorporate Vendor Overhaul Recommendations for Class 1E Medium Voltage Circuit Breaker Preventive Maintenance Program.
1R20 Refueling and Other Outage Activities
a. Inspection Scope
During the stations Unit 1 refueling outage that concluded on November 7, 2017, the inspectors evaluated the licensees outage activities. The inspectors verified that the licensee considered risk in developing and implementing the outage plan, appropriately managed personnel fatigue, and developed mitigation strategies for losses of key safety functions. This verification included the following:
- Review of the licensees outage plan prior to the outage
- Review and verification of the licensees fatigue management activities
- Monitoring of shut-down and cool-down activities
- Verification that the licensee maintained defense-in-depth during outage activities
- Observation and review of reduced-inventory and lowered-inventory activities
- Observation and review of fuel handling activities
- Monitoring of heat-up and startup activities These activities constituted completion of one refueling outage sample as defined in Inspection Procedure 71111.20.
b. Findings
No findings were identified.
1R22 Surveillance Testing
a. Inspection Scope
The inspectors observed four risk-significant surveillance tests and reviewed test results to verify that these tests adequately demonstrated that the structures, systems, and components (SSCs) were capable of performing their safety functions:
In-service tests:
- October 23, 2017, Unit 1 auxiliary feedwater pump B surveillance test Containment isolation valve surveillance tests:
- October 23, 2017, Unit 1 letdown heat exchanger valve CH-516 (penetration 40)
Other surveillance tests:
- October 31, 2017, Unit 1 pressurizer spray control valve RCE-100F actuator drop test
- November 8, 2017, Unit 3 surveillance test of steam generator 2 downcomer blowdown sample isolation valve SG-223 The inspectors verified that these tests met technical specification requirements, that the licensee performed the tests in accordance with their procedures, and that the results of the test satisfied appropriate acceptance criteria.
These activities constituted completion of four surveillance testing inspection samples, as defined in Inspection Procedure 71111.22.
b. Findings
No findings were identified.
Cornerstone: Emergency Preparedness
1EP4 Emergency Action Level and Emergency Plan Changes
a. Inspection Scope
The inspector performed an in-office review of Palo Verde Nuclear Generating Stations Emergency Plan, Revisions 59 and 60. Revision 59 addressed the implementation of a revised emergency action level (EAL) scheme approved by the NRC in License Amendment 198 on September 8, 2016. Revision 60 addressed the following changes:
- Revised the hydrogen concentration level used for evaluation of EALs associated with the containment fission product barrier, based on updated information in the licensees emergency operating procedures
- Revised the description of the Radiation Protection Coordinator in the Technical Support Center to more clearly describe the individuals role and responsibilities
- Updated references to a local support medical facility which recently changed its name
- Completed numerous editorial changes This revision was compared to its previous revision, to the criteria of NUREG-0654, Criteria for Preparation and Evaluation of Radiological Emergency Response Plans and Preparedness in Support of Nuclear Power Plants, Revision 1, to Nuclear Energy Institute Report 99-01, Emergency Action Level Methodology, Revision 6, and to the standards in 10 CFR 50.47(b) to determine if the revision adequately implemented the requirements of 10 CFR 50.54(q)(3) and 50.54(q)(4). The inspector verified that the revisions did not decrease the effectiveness of the emergency plan. This review was not documented in a safety evaluation report and did not constitute approval of licensee-generated changes; therefore, these revisions are subject to future inspection.
These activities constitute completion of two emergency action level and emergency plan changes sample as defined in Inspection Procedure 71114.04.
b. Findings
No findings were identified.
RADIATION SAFETY
Cornerstones: Public Radiation Safety and Occupational Radiation Safety
2RS1 Radiological Hazard Assessment and Exposure Controls
a. Inspection Scope
The inspectors evaluated the licensees performance in assessing the radiological hazards in the workplace associated with licensed activities. The inspectors assessed the licensees implementation of appropriate radiation monitoring and exposure control measures for both individual and collective exposures. During the inspection, the inspectors interviewed licensee personnel, walked down various areas in the plant, performed independent radiation dose rate measurements, and observed postings and physical controls. The inspectors reviewed licensee performance in the following areas:
- Radiological hazard assessment, including a review of the plants radiological source terms and associated radiological hazards. The inspectors also reviewed the licensees radiological survey program to determine whether radiological hazards were properly identified for routine and non-routine activities and assessed for changes in plant operations.
- Instructions to workers including radiation work permit requirements and restrictions, actions for electronic dosimeter alarms, changing radiological condition, and radioactive material container labeling.
- Contamination and radioactive material control, including release of potentially contaminated material from the radiologically controlled area, radiological survey performance, radiation instrument sensitivities, material control and release criteria, and control and accountability of sealed radioactive sources.
- Radiological hazards control and work coverage. During walkdowns of the facility and job performance observations, the inspectors evaluated ambient radiological conditions, radiological postings, adequacy of radiological controls, radiation protection job coverage, and contamination controls. The inspectors also evaluated dosimetry selection and placement as well as the use of dosimetry in areas with significant dose rate gradients. The inspectors examined the licensees controls for items stored in the spent fuel pool and evaluated airborne radioactivity controls and monitoring.
- High radiation area and very high radiation area controls. During plant walkdowns, the inspectors verified the adequacy of posting and physical controls, including areas of the plant with the potential to become risk-significant high radiation areas.
- Radiation worker performance and radiation protection technician proficiency with respect to radiation protection work requirements. The inspectors determined if workers were aware of significant radiological conditions in their workplace, radiation work permit controls/limits in place, and electronic dosimeter dose and dose rate set points. The inspectors observed radiation protection technician job performance, including the performance of radiation surveys.
- Problem identification and resolution for radiological hazard assessment and exposure controls. The inspectors reviewed audits, self-assessments, and corrective action program documents to verify problems were being identified and properly addressed for resolution.
These activities constitute completion of the seven required samples of radiological hazard assessment and exposure control program, as defined in Inspection Procedure 71124.01.
b. Findings
No findings were identified.
2RS2 Occupational ALARA Planning and Controls
a. Inspection Scope
The inspectors assessed licensee performance with respect to maintaining individual and collective radiation exposures as low as is reasonably achievable (ALARA). The inspectors performed this portion of the attachment during the refueling outage, in order to directly observe the licensees ALARA process activities including planning, implementation of radiological work controls, execution of work activities, and ALARA review of work-in-progress. During the inspection the inspectors interviewed licensee personnel, reviewed licensee documents, and evaluated licensee performance in the following areas:
- Implementation of ALARA and radiological work controls. The inspectors observed pre-job briefings, reviewed planned radiological administrative, operational, and engineering controls, and compared the planned controls to field activities.
- Radiation worker and radiation protection technician performance during work activities performed in radiation areas, airborne radioactivity areas, or high radiation areas.
- Problem identification and resolution for ALARA and radiological work controls.
The inspectors reviewed audits, self-assessments, and corrective action program documents to verify problems were being identified and properly addressed for resolution.
These activities constitute completion of three samples of the five required samples of occupational ALARA planning and controls program, as defined in Inspection Procedure 71124.02, and completes the inspection.
b. Findings
No findings were identified.
OTHER ACTIVITIES
Cornerstones: Initiating Events, Mitigating Systems, Barrier Integrity, Emergency Preparedness, Public Radiation Safety, Occupational Radiation Safety, and security
4OA1 Performance Indicator Verification
.1 Occupational Exposure Control Effectiveness (OR01)
a. Inspection Scope
The inspectors verified that there were no unplanned exposures or losses of radiological control over locked high radiation areas and very high radiation areas during the period of March 31, 2016, to September 30, 2017. The inspectors reviewed a sample of radiologically controlled area exit transactions showing exposures greater than 100 millirem. The inspectors used definitions and guidance contained in Nuclear Energy Institute Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7, to determine the accuracy of the reported data.
These activities constituted verification of the occupational exposure control effectiveness performance indicator as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
.2 Radiological Effluent Technical Specifications (RETS)/Offsite Dose Calculation Manual
(ODCM) Radiological Effluent Occurrences (PR01)
a. Inspection Scope
The inspectors reviewed corrective action program records for liquid or gaseous effluent releases that occurred between March 31, 2016, and September 30, 2017, and were reported to the NRC to verify the performance indicator data. The inspectors used definitions and guidance contained in Nuclear Energy Institute Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7, to determine the accuracy of the reported data.
These activities constituted verification of the radiological effluent technical specifications (RETS)/offsite dose calculation manual (ODCM) radiological effluent occurrences performance indicator as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
4OA2 Problem Identification and Resolution
.1 Routine Review
a. Inspection Scope
Throughout the inspection period, the inspectors performed daily reviews of items entered into the licensees corrective action program and periodically attended the licensees condition report screening meetings. The inspectors verified that licensee personnel were identifying problems at an appropriate threshold and entering these problems into the corrective action program for resolution. The inspectors verified that the licensee developed and implemented corrective actions commensurate with the significance of the problems identified. The inspectors also reviewed the licensees problem identification and resolution activities during the performance of the other inspection activities documented in this report.
b. Findings
No findings were identified.
.2 Semiannual Trend Review
a. Inspection Scope
The inspectors reviewed the licensees corrective action program, performance indicators, system health reports, and other documentation to identify trends that might indicate the existence of a more significant safety issue. The inspectors verified that the licensee was taking corrective actions to address identified adverse trends.
These activities constituted completion of one semiannual trend review sample, as defined in Inspection Procedure 71152.
b. Observations and Assessments The inspectors reviewed main control room deficiencies and other issues that could potentially challenge operators in performing their duties. The inspectors reviewed the licensees procedures for identifying, assessing, tracking, and communicating deficiencies associated with main control room instrumentation and controls. Multiple procedures define these processes, including:
- 40DP-9OP15, Operator Challenges and Discrepancy Tracking
- 40DP-9OP09, System Status Control
- 40DP-9OP33, Shift Turnover The inspectors observed that the licensee appears to be identifying control room deficiencies at an appropriate low threshold. However, the inspectors also noted that the licensee maintains several different mechanisms for tracking control room deficiencies. These tracking mechanisms include:
- Control room discrepancy log
- Lit annunciator log
- Jumpered alarm log
- Operator challenges log
- Temporary note (T-note) database
- Equipment status tag (EST) log
- Control room turnover comments document The control room turnover comments document is the list most frequently relied upon to communicate deficient conditions from one operating crew to another. However, of the tracking mechanisms listed above, the control room turnover comments document is the least well defined and controlled. According to the Shift Turnover procedure, 40DP-9OP33, items entered in the turnover comments document may include anything of interest to the operating crew. This broad definition permits the standards for incorporating comments to vary slightly from one operating crew to another and has resulted in producing a turnover comments document that largely consists of a very extensive list of minor control room deficiencies. The variable crew priorities and lack of procedural controls do not clearly delineate the prioritization or anticipated resolution date of the individual issues.
The inspectors shared these observations with licensee operations management. The inspectors noted that there was substantial effort during the Unit 1, fall 2017 refueling outage to reduce the backlog of items on the Unit 1 control room deficiencies lists. Also, the inspectors have observed that all turnover comments entries are now accompanied by an associated condition report or corrective maintenance work order number. The licensee has also begun efforts to implement a singular coding and tracking tool within the existing work management database to ensure that all issues that could potentially challenge operators are being maintained visible and prioritized on a single tracking list.
c. Findings
No findings were identified.
.3 Annual Follow-up of Selected Issues
a. Inspection Scope
The inspectors selected one issue for an in-depth follow-up:
- On November 6, 2017, lubrication laboratory sample analysis The inspectors assessed the licensees problem identification threshold and conduct of oil sample analysis. The inspectors verified that the licensee appropriately prioritized the planned corrective actions and that these actions were adequate to addressing any adverse conditions identified in their lubrication analysis.
These activities constituted completion of one annual follow-up sample as defined in Inspection Procedure 71152.
b. Findings
No findings were identified.
4OA6 Meetings, Including Exit
Exit Meeting Summary
On October 18, 2017, the inspectors presented the inspection results to Mr. Jack Cadogan, Senior Vice President, Site Operations, and other members of the licensee staff. The licensee acknowledged the issues presented. The licensee confirmed that any proprietary information reviewed by the inspectors had been returned or destroyed.
On October 20, 2017, the inspectors presented the radiation safety inspection results to Mr. Mike McLaughlin, Vice President, Operations Support, and other members of the licensee staff. The licensee acknowledged the issues presented. The licensee confirmed that any proprietary information reviewed by the inspectors had been returned or destroyed.
On November 30, 2017, the inspector conducted a telephonic exit meeting to present the results of the in-office inspection of changes to the licensees emergency plan and emergency action levels to Ms. Charlotte Shields, Emergency Preparedness Manager, and other members of the licensee staff. The licensee acknowledged the issues presented.
On December 22, 2017, the inspector presented the inspection results to Mr. David Oliver, Regulatory Exam Author, of the results of the licensed operator requalification program inspection. The licensee representative acknowledged the results presented. The inspector asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identified.
On January 11, 2018, the inspectors presented the inspection results to Ms. Maria Lacal, Senior Vice President, Regulatory and Oversite, and other members of the licensee staff. The licensee acknowledged the issues presented. The licensee confirmed that any proprietary information reviewed by the inspectors had been returned or destroyed.
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
- J. Cadogan, Senior Vice President, Site Operations
- M. Lacal, Senior Vice President, Regulatory and Oversite
- M. McLaughlin, Vice President, Operations Support
- H. Ridenour, Director, Maintenance
- C. Moeller, Director, Technical Support, Radiation Protection/Chemistry
- H. Nelson, Director, Projects
- M. McGhee, Department Leader, Nuclear Regulatory Affairs
- D. Elkinton, Section Leader, Nuclear Regulatory Affairs
- M. DiLorenzo, Section Leader, Compliance/ Nuclear Regulatory Affairs
- L. Grusecki, Supervisor, Radiation Protection
- S. Lantz, Supervisor, Radiation Protection
- R. Routolo, Superintendent of Tech Support, Radiation Protection
- D. Heckman, Senior Consultant, Nuclear Regulatory Affairs
- G. Nelson, Senior Health Physicist, Radiation Protection
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Opened and Closed
- 05000529-2017004-01 NCV Failure to Iincorporate Vendor Overhaul Recommendations for Class 1E Medium Voltage Circuit Breaker Preventive Maintenance Program. (Section 1R19)