IR 05000275/2015001
| ML15111A547 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 05/05/2015 |
| From: | Webb Patricia Walker NRC/RGN-IV/DRP/RPB-A |
| To: | Halpin E Pacific Gas & Electric Co |
| Walker W | |
| References | |
| IR 2015001 | |
| Download: ML15111A547 (33) | |
Text
May 5, 2015
SUBJECT:
DIABLO CANYON POWER PLANT - NRC INTEGRATED INSPECTION REPORT 05000275/2015001 and 05000323/2015001
Dear Mr. Halpin:
On March 31, 2015, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Diablo Canyon Power Plant Units 1 and 2. On April 9, 2015, the NRC inspectors discussed the results of this inspection with Mr. J. Welsch and other members of your staff.
Inspectors documented the results of this inspection in the enclosed inspection 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 NRC 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, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; and the NRC resident inspector at the Diablo Canyon Power Plant.
In accordance with Title 10 of the Code of Federal Regulations (10 CFR) 2.390, Public Inspections, Exemptions, Requests for Withholding, a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRCs Public Document Room or from the Publicly Available Records (PARS) component of the NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,
/RA/
Wayne C. Walker, Chief Project Branch A Division of Reactor Projects
Docket Nos. 05000275, 05000323 License Nos. DPR-80, DPR-82
Enclosure:
Inspection Report 05000275/2015001 and 05000323/2015001 w/ Attachment: Supplemental Information
REGION IV==
Docket:
05000275; 05000323 License:
05000275/2015001; 05000323/2015001 Licensee:
Pacific Gas and Electric Company Facility:
Diablo Canyon Power Plant, Units 1 and 2 Location:
7 1/2 miles NW of Avila Beach Avila Beach, CA Dates:
January 1, 2015 through March 31, 2015 Inspectors: T. Hipschman, Senior Resident Inspector J. Reynoso, Resident Inspector M. Bloodgood, Project Engineer G. Guerra, CHP, Emergency Preparedness Inspector Approved By:
Wayne Walker, Chief Chief, Project Branch A Division of Reactor Projects
- 2 -
Enclosure
SUMMARY
IR 05000275/2015001, 05000323/2015001; 01/01/2015 - 03/21/2015; Diablo Canyon Power
Plant; Follow-up of Events.
The inspection activities described in this report were performed between January 1 and March 31, 2015, by the resident inspectors at Diablo Canyon and inspectors from the NRCs Region IV office. One finding of very low safety significance (Green) is documented in this report. This finding involved a violation of NRC requirements. The significance of inspection findings is indicated by their color (Green, White, Yellow, or Red), which is determined using Inspection Manual Chapter 0609, Significance Determination Process. Their cross-cutting aspects are determined using Inspection Manual Chapter 0310, Aspects within the Cross-Cutting Areas. 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.
Cornerstone: Mitigating Systems
- Green.
The inspectors documented a self-revealing violation of 10 CFR Part 50,
Appendix B, Criterion III, Design Control, for the licensees failure to ensure that design control measures shall provide for verifying or checking the adequacy of design by the performance of design reviews and design control measures shall be applied to items such as maintenance, and repair; and delineation of acceptance criteria for inspections and tests. Specifically, the licensee failed to incorporate a design modification to remove a terminal block cover during the original installation of emergency diesel generator 2-3.
This modification was identified as a corrective action following previous trips of emergency diesel generators 1-2 and 1-1.
The licensees failure to identify that a terminal block cover was removed from emergency diesel generator 2-3 as corrective actions following previous trips of emergency diesel generators 1-2 and 1-1, and to incorporate this modification into the design and installation of emergency diesel generator 2-3, was a performance deficiency. This performance deficiency was more than minor because it is associated with the design control attribute of the Mitigating Systems cornerstone objective and adversely affected the objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). Specifically, the performance deficiency adversely affected the diesel generators capability to operate loaded for the technical specification required time.
Using Inspection Manual Chapter 0609, Attachment 04, Initial Characterization of Findings, and Appendix A, The Significance Determination Process (SDP) For Findings At-Power, dated July 1, 2012, the inspectors determined that the finding could not be screened as Green, or very low safety significance, due to loss of a function of a single train for greater than its technical specification outage time. As a result, a detailed risk evaluation was performed by a senior risk analyst. The detailed risk evaluation determined that the finding was Green, or very low safety significance. This finding did not have a cross-cutting aspect because the most significant contributor did not reflect current licensee performance. (Section 4OA3)
PLANT STATUS
Unit 1 commenced a reactor start-up on January 4, 2015, following a forced outage to repair a cracked weld in the residual heat removal system and returned to full power on January 5, 2015, and remained at full power through the end of the inspection period.
Unit 2 began the inspection period at full power and remained at or near full power through the end of the inspection period.
REPORT DETAILS
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
1R01 Adverse Weather Protection
.1 Readiness for Impending Adverse Weather Conditions
a. Inspection Scope
On February 6, 2015, the inspectors completed an inspection of the stations readiness for impending adverse weather conditions. The inspectors reviewed plant design features, the licensees procedures to respond to severe rains, and the licensees monitoring and contingency implementation of these procedures. The inspectors evaluated operator staffing and accessibility of controls and indications for those systems required to control the plant.
These activities constituted one sample of readiness for impending adverse weather conditions, as defined in Inspection Procedure 71111.01.
b. Findings
No findings were identified.
1R04 Equipment Alignment
Partial Walkdown
a. Inspection Scope
The inspectors performed partial system walk-downs of the following risk-significant systems:
January 12, 2015, Unit 1, emergency diesel generator, EDG 1-1, air start system alignment
February 4-5, 2015, Unit 1 and 2, auxiliary seawater alignment
February 23, 2015, Unit 2, component cooling water system alignment
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
.1 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 four plant areas important to safety:
January 14-15, 2015, Unit 1, emergency diesel generator and radiator fire areas located in turbine building 85 foot and 119 foot elevations
January 28, 2015, Units 1 and 2, radioactive control areas and H block, 100 foot elevation areas
February 4, 2015, Units 1 and 2, intake structure fire areas located (-2) foot and 18 foot elevations and Lot 5 at the 85 foot elevation
February 26, 2015, Units 1 and 2, emergency diesel generator rooms 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 four quarterly inspection samples, as defined in Inspection Procedure 71111.05.
b. Findings
No findings were identified.
.2 Annual Inspection
a. Inspection Scope
On March 26, 2015, the inspectors observed fire brigade activation for an unannounced fire drill. Based on this observation and review of the fire brigade training, the inspectors evaluated the readiness of the plant fire brigade to fight fires. The inspectors verified
that the licensee staff identified deficiencies; openly discussed them in a self-critical manner at the drill debrief, and took appropriate corrective actions. Specific attributes evaluated were:
- proper wearing of turnout gear and self-contained breathing apparatus;
- proper use and layout of fire hoses;
- employment of appropriate firefighting techniques;
- sufficient firefighting equipment brought to the scene;
- effectiveness of fire brigade leader communications, command, and control;
- search for victims and propagation of the fire into other plant areas;
- smoke removal operations;
- utilization of pre-planned strategies;
- adherence to the pre-planned drill scenario;
- compliance training requirements; and
- drill objectives.
Documents reviewed are listed in the attachment to this report.
These activities constituted one annual fire protection inspection sample as defined in IP 71111.05-05.
b. Findings
No findings were identified.
1R06 Flood Protection Measures
a. Inspection Scope
On March 30, 2015, the inspectors completed an inspection of the stations ability to mitigate flooding due to internal causes. After reviewing the licensees flooding analysis, the inspectors chose one plant area containing risk-significant structures, systems, and components that was susceptible to flooding:
Unit 1 and 2, auxiliary building at 100 foot elevation internal flooding inspection
The inspectors reviewed plant design features and licensee procedures for coping with internal flooding. The inspectors walked down the selected areas to inspect the design features, including the material condition of seals, drains, and flood barriers. The inspectors evaluated whether operator actions credited for flood mitigation could be successfully accomplished.
These activities constitute completion of one flood protection measures sample, as defined in Inspection Procedure 71111.06
b. Findings
No findings were identified.
1R11 Licensed Operator Requalification Program and Licensed Operator Performance
.1 Review of Licensed Operator Requalification
a. Inspection Scope
On February 19, 2015, the inspectors observed a simulator training session for a licensed operating crew. The inspectors assessed the performance of the operators and the evaluators critique of their performance.
These activities constitute 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
The inspectors observed the performance of on-shift licensed operators in the plants main control room. The inspectors observed the operators performance of the following activities:
January 4, 2015, 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 start-up of the reactor following a forced outage.
March 31, 2015, 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 numerous spurious fire alarms that included fire pump start and fire alarms trouble. In addition, the inspectors assessed the operators adherence to plant procedures, including alarm response procedure OP K-26 and other operations department policies.
In addition, the inspectors assessed the operators adherence to plant procedures, including conduct of operations procedure and other operations department policies.
These activities constitute completion of two quarterly licensed operator performance samples, as defined in Inspection Procedure 71111.11.
b. Findings
No findings were identified.
1R12 Maintenance Effectiveness
a. Inspection Scope
The inspectors reviewed three instances of degraded performance or condition of safety-related structures, systems, and components (SSCs):
January 9, 2015, Unit 1, emergency diesel generator 1-2, lube oil heat exchanger leak from a failed O-ring
January 12-14, 2015, emergency diesel generator maintenance rule goal setting evaluation
March 15, 2015, PCV-474 pressurizer power operated relief value due to excessive leakage The inspectors reviewed the extent of condition of possible common cause SSC failures and evaluated the adequacy of the licensees corrective actions. The inspectors reviewed the licensees work practices to evaluate whether these may have played a role in the degradation of the SSCs. The inspectors assessed the licensees characterization of the degradation in accordance with 10 CFR 50.65 (the Maintenance Rule), and verified that the licensee was appropriately tracking degraded performance and conditions in accordance with the Maintenance Rule.
These activities constituted completion of three maintenance effectiveness samples, 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 four 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:
January 27-28, 2015, Unit 1, volume control tank hydrogen regulator repairs
February 9, 2015, Unit 2, containment fan cooling unit 2-1 and auxiliary saltwater pump 2-2 timer relay replacement
February 25, 2015, spent fuel pool cooling equipment posting requirements
March 6, 2015, preparations for 230 kV switchyard maintenance 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 three emergent work activities that had the potential to cause an initiating event, to affect the functional capability of mitigating systems, or to impact barrier integrity:
January 6, 2015, Unit 1, emergent risk evaluation due to leak on RHR system relief valve RV-8708
January 10, 2015, Unit 1, emergency diesel generator 1-2 extended outage risk management actions
March 4, 2015, RCS-2-8000A valve stroke testing 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.
These activities constitute completion of seven 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 seven operability determinations that the licensee performed for degraded or nonconforming structures, systems, or components (SSCs):
January 2 2015, operability determination of Unit 1 residual heat removal system
January 4, 2015, operability determination of Unit 2, emergency diesel generator EDG 2-3 jacket water pump leakage
January 6-8, 2015, operability determination of Unit 1, radiation monitor RM-30, high range containment detector
February 2, 2015, operability determination of Unit 2 pressurizer relief tank
February 9, 2015, operability determination of Unit 2 auxiliary salt water pump 2-1
March 4, 2015, operability determination of Unit 2 PCV-474, pressurizer power operated relief valve
March 12, 2015, Units 1 and 2 operability assessment of Fukushima Near-Term Task Force Recommendation 2.1: Seismic and Seismic Hazard Screening
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 constitute completion of seven operability and functionality review samples, as defined in Inspection Procedure 71111.15.
b. Findings
No findings were identified.
1R18 Plant Modifications
.1 Temporary Modifications
a. Inspection Scope
On January 13-14, 2015, the inspectors reviewed a temporary modification on Unit 2 to modify the temporary temperature monitoring sensors in the emergency diesel intake areas.
The inspectors verified that the licensee had appropriate procedures in place to install this temporary modification in accordance with technically adequate design documents.
The inspectors verified that this modification did not adversely impact the operability or availability of affected SSCs. The inspectors reviewed design documentation and plant procedures affected by the modification to verify the licensee maintained configuration control.
These activities constitute completion of one sample of temporary modifications, as defined in Inspection Procedure 71111.18.
b. Findings
No findings were identified.
.2 Permanent Modifications
a. Inspection Scope
The inspectors reviewed two permanent plant modifications that affected risk-significant structures, systems, and components (SSCs):
January 5, 2015, Unit 1, residual heat removal system piping supports
February 12-13, 2015, Unit 2, containment fan cooling unit 2-1 and auxiliary saltwater pump 2-2 timer relay replacement The inspectors reviewed the design and implementation of the modifications. The inspectors verified that work activities involved in implementing the modifications did not
adversely impact operator actions that may be required in response to an emergency or other unplanned event. The inspectors verified that post-modification testing was adequate to establish the operability of the SSCs as modified.
These activities constitute completion of two samples of permanent modifications, as defined in Inspection Procedure 71111.18.
b. Findings
No findings were identified.
1R19 Post-Maintenance Testing
a. Inspection Scope
The inspectors reviewed six post-maintenance testing activities that affected risk-significant structures, systems, or components (SSCs):
January 2, 2015, Unit 1, residual heat removal system following repairs and modifications
January 7, 2015, Unit 1, emergency diesel generator EDG 1-2, following maintenance
January 20, 2015, Unit 2, turbine driven auxiliary feedwater pump 2-1, lubrication and inspection post maintenance testing
February 12, 2015, Unit 2, containment fan cooling unit 2-1 and auxiliary saltwater pump 2-2 timer relay replacement
February 20, 2015, Unit 2, auxiliary salt water pump 2-1 following pressure switch calibration
March 10, 2015, Unit 2, component cooling water pump 2-1 following maintenance 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 constitute completion of six post-maintenance testing inspection samples, as defined in Inspection Procedure 71111.19.
b. Findings
No findings were identified.
1R20 Refueling and Other Outage Activities
a. Inspection Scope
During the Unit 1 forced outage that concluded on January 4, 2015, 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
Monitoring of shut-down and cool-down activities
Verification that the licensee maintained defense-in-depth during outage activities
Monitoring of heat-up and startup activities
These activities constitute completion of one forced outage activities sample, as defined in Inspection Procedure 71111.20.
b. Findings
No findings were identified.
1R22 Surveillance Testing
a. Inspection Scope
The inspectors observed six 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:
January 20, 2015, Unit 2, auxiliary feedwater surveillance stroke test of level control valves LCV 106-109 and steam admission valves
February 10, 2015, Unit 2, auxiliary salt water pump 2-1 Reactor coolant system leak detection tests:
February 4-6, 2015, reactor coolant system leak detection system surveillance
Other surveillance tests:
February 4, 2015, Unit 1, source range monitor N-31 channel calibration and surveillance
February 12, 2015, Unit 2, emergency diesel generator 2-3 surveillance test following replacement of safety injection timing relays
March 10, 2015, Unit 2 containment fan cooler unit sequencer timing
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. The inspectors verified that the licensee restored the operability of the affected SSCs following testing.
These activities constitute completion of six 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 the following document changes to the Diablo Canyon Power Plant, Units 1 and 2, Emergency Plan:
Emergency Plan Section 1, Definitions and Abbreviations, Revision 4.07;
Emergency Plan Section 2, Scope and Applicability, Revision 4.04;
Emergency Plan Section 4, Emergency Conditions, Revision 4.14;
Emergency Plan Section 5, Organizational Control of Emergencies, Revision 4.15;
Emergency Plan Section 6, Emergency Measures, Revision 4.14;
Emergency Plan Section 7, Emergency Facilities and Equipment, Revision 4.19;
Emergency Plan Section 8, Maintaining Emergency Preparedness, Revision 4.12;
Emergency Plan Appendix A, Procedures, Revision 4.06;
Emergency Plan Appendix F, ERO On-Shift Staffing Analysis Report, Revision 4.01;
Emergency Plan Appendix G, Protective Action Recommendation (PAR)
Strategy Bases, Revision 4.00;
Emergency Procedure EP G-3, Emergency Notifications of Off-Site Agencies, Revision 57;
Emergency Procedure EP RB-10, Protective Action Recommendations, Revision 18;
Emergency Procedure EP RB-16, Operating Instructions for the EARS Computer Program, Revision 11.
The changes implement the following:
Implemented requirements for challenging drills and exercises;
Added a Shift Phone Talker position to on-shift staffing;
Revised protective action recommendation strategy to align with new federal guidance in NUREG-0654, Supplement 3, Criteria for Preparation and Evaluation of Radiological Emergency Response Plans and Preparedness in Support of Nuclear Power Plants - Guidance for Protective Action Strategies, Revision 1;
Implementation of dose assessment capabilities in the control room;
Implementation of multi-unit dose assessment.
Additionally, several editorial corrections were made. These changes were submitted to the NRC in the following letters:
DCL-14-117, dated December 16, 2014;
DCL-15-002, dated January 8, 2015;
DCL-15-003, dated January 12, 2015;
DCL-15-004, dated January 15, 2015.
These revisions were compared to previous revisions, 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, 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 reduce 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.
Additionally, the inspector reviewed corrective action program document, Notification 50692872, documenting the licensees emergency plan and implementing procedure change submittal processes required in accordance with 10 CFR 50.54(q)(5).
The inspector noted that the licensee planned enhancements to facilitate future plan change submittal reviews.
These activities constitute completion of 13 emergency action level and emergency plan change samples as defined in Inspection Procedure 71114.04.
b. Findings
No findings were identified.
1EP6 Drill Evaluation
.1 Emergency Preparedness Drill Observation
a. Inspection Scope
During the inspection period, the inspectors observed two separate emergency preparedness drills, to verify the adequacy and capability of the licensees assessment of drill performance.
On January 27, 2015, the inspectors reviewed the drill scenario, observed the drill from the simulator, and attended the post-drill critique.
On March 11, 2015, the inspectors reviewed the drill scenario, observed the drill from the simulator and technical support center (TSC), and attended the post-drill critique.
During both emergency preparedness drill observations, the inspectors verified that the licensees emergency classifications, off site notifications, and protective action recommendations were appropriate and timely. The inspectors verified that any emergency preparedness weaknesses were appropriately identified by the licensee in the post-drill critiques and entered into the corrective action program for resolution.
These activities constitute completion of two emergency preparedness drill observation samples, as defined in Inspection Procedure 71114.06.
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 Unplanned Scrams per 7000 Critical Hours (IE01)
a. Inspection Scope
The inspectors reviewed licensee event reports (LERs) for the period of January 1, 2014, through December 31, 2014, to determine the number of scrams that occurred. The inspectors compared the number of scrams reported in these LERs to the number reported for the performance indicator. Additionally, the inspectors sampled monthly operating logs to verify the number of critical hours during the period. 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 data reported.
These activities constituted verification of the unplanned scrams per 7000 critical hours performance indicator for Units 1 and 2, as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
.2 Unplanned Power Changes per 7000 Critical Hours (IE03)
a. Inspection Scope
The inspectors reviewed operating logs, corrective action program records, and monthly operating reports for the period of January 1, 2014, through December 31, 2014, to determine the number of unplanned power changes that occurred. The inspectors compared the number of unplanned power changes documented to the number reported for the performance indicator. Additionally, the inspectors sampled monthly operating logs to verify the number of critical hours during the period. 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 data reported.
These activities constituted verification of the unplanned power outages per 7000 critical hours performance indicator for Units 1 and 2, as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
.3 Unplanned Scrams with Complications (IE04)
a. Inspection Scope
The inspectors reviewed the licensees basis for including or excluding in this performance indicator each scram that occurred between January 1, 2014, and December 31, 2014. 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 data reported.
These activities constituted verification of the unplanned scrams with complications performance indicator for Units 1 and 2, as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
4OA2 Problem Identification and Resolution
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 notification 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.
4OA3 Follow-up of Events and Notices of Enforcement Discretion
.1 (Closed) LER 05000323/2-2013-004-00 and -01:
Technical Specification 3.8.1 Not Met Due to Failed Wire Lug on Emergency Diesel Generator 2-3
a. Inspection Scope
On June 8, 2013, Emergency Diesel Generator (EDG) 2-3 tripped due to differential overcurrent during a scheduled Technical Specification Surveillance Test, STP M-9A, 24-hour load run. Technical Specification Surveillance Requirement 3.8.1.14 requires an emergency diesel generator to operate loaded for a minimum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Cyclic fatigue failure of a wire lug in the EDG 2-3 current differential protection circuit caused an automatic EDG shutdown 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> and 42 minutes into the run. The wire lug was replaced and the EDG was returned to service on June 9, 2013.
b. Findings
Introduction.
The inspectors reviewed a Green, self-revealing violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, for the licensees failure to ensure that design control measures shall provide for verifying or checking the adequacy of design by the performance of design reviews and design control measures shall be applied to items such as maintenance, and repair; and delineation of acceptance criteria for inspections and tests. Specifically, the licensee failed to incorporate a design modification to remove a terminal block cover during the original installation of emergency diesel generator (EDG) 2-3. This modification was identified as a corrective action following trips of EDGs 1-2 and 1-1.
Description.
On June 8, 2013, emergency diesel generator (EDG) 2-3 tripped due to differential overcurrent during a scheduled Technical Specification Surveillance Test, STP M-9A, 24-hour load run. Technical Specification Surveillance Requirement 3.8.1.14 requires an emergency diesel generator to operate loaded for a minimum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Cyclic fatigue failure of a wire lug in the EDG 2-3 current differential protection circuit caused an automatic EDG shutdown 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> and 42 minutes into the test.
The licensee initiated Notification 50567942 to investigate the trip of EDG 2-3. The investigation determined that the broken lug was located in the junction box (BTA503)containing the current transformer test switches. The failure of the lug was categorized as a cyclic failure due to vibration experienced during EDG operation, as well as wire fretting due to contact with the terminal block dust cover.
During the licensees apparent cause evaluation, the licensee identified that EDG 2-3 was the only EDG with the installed dust cover in the junction box containing the Current Transformer Test switches. Previous plant operating experience identified that EDG 1-2 tripped in December 1989, (Action Request A0172916) due to a differential relay trip caused from a broken wire lug in the current transformer output circuitry. Additionally the inspectors identified an additional trip of EDG 1-1 in April 1990, (Action Request A0185742) due a differential relay trip which resulted from a broken terminal lug. The failures of the lugs were determined, in Quality Evaluation Q0007424, to be the result of cyclic vibration of the wire due to terminal box vibration during EDG operations. The licensees corrective actions for EDGs 1-1, 1-2, 1-3, 2-1 and 2-2 included rerouting the associated wires and removing the associated terminal box cover. The lessons learned from the EDG 1-1 and 1-2 events were not incorporated into the design and installation of EDG 2-3 in 1992-1993. This resulted in the terminal block cover remaining installed in the junction box on EDG 2-3 and lack of maintenance direction for the inspection of the terminal box.
Prior to the failure, on November 30, 2012, Procedure STP M-81G, Diesel Engine Generator Inspection (Electrical Every Refueling Cycle), was partially performed in accordance with Work Order 64045607. This work order included completion of high potential testing in accordance with Procedure MP E-57.14A, PI and Hipot Testing.
This testing required the removal and reinstallation of the terminal block cover in Junction Box BTA503. Procedure MP E-57.14A did not specify inspection requirements for the terminations or reinstallation of the terminal cover.
During the apparent cause evaluation in 2013 the licensee permanently removed the terminal block cover as a corrective action, previously performed on the other five EDGs, and identified as a prudent action to revise procedures to inspect terminations for tightness and cyclic fatigue.
Analysis.
The licensees failure to identify that a terminal block cover was removed from emergency diesel generator (EDG) 2-3 as corrective actions following previous trips of EDGs 1-2 and 1-1 and to incorporate this modification into the design and installation of EDG 2-3 was a performance deficiency. This performance deficiency was more than minor because it is associated with the design control attribute of the Mitigating Systems cornerstone objective and adversely affected the objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). Specifically, the performance deficiency adversely affected the diesel generators capability to operate loaded for the technical specification required time. Using Inspection Manual Chapter 0609, Attachment 04, Initial Characterization of Findings, and Appendix A, The Significance Determination Process (SDP) For Findings At-Power, dated July 1, 2012, the inspectors determined that the finding could not be screened as Green, or very low safety significance due to loss of a function of a single train for greater than its technical specification outage time.
As a result, a detailed risk evaluation was performed by a senior risk analyst.
The Region IV senior reactor analyst performed a detailed risk evaluation in accordance with Manual Chapter 0609, Appendix A, Section 6.0, Detailed Risk Evaluation. The detailed risk evaluation resulted in a calculated change in core damage frequency of 9.87 E-7. The dominating sequences in the analysis included an unrecovered station blackout beyond battery depletion and by an unrecoverable seismically-induced loss of offsite power. Additionally, the analyst determined that the finding did not involve a
significant increase in the risk of a large, early release of radiation. Because the calculated change in core damage frequency was less than 1E-6, the finding was determined to be of very low safety significance (Green).
This finding was determined not to have a cross-cutting aspect because it did not reflect current licensee performance.
Enforcement.
Title 10 of the Code of Federal Regulations, Part 50, Appendix B, Criterion III, Design Control, requires, in part, that design control measures shall provide for verifying or checking the adequacy of design, such as by the performance of design reviews and design control measures shall be applied to items such as maintenance, and repair; and delineation of acceptance criteria for inspections and tests.
Contrary to the above, the licensee failed to identify that a terminal block cover that was removed from the existing diesel generators as corrective actions following previous trips of emergency diesel generators (EDGs) 1-2 and 1-1, and incorporate this modification into the design and installation of EDG 2-3. This resulted in the failure of the EDG 2-3 to meet Technical Specification Surveillance Requirement 3.8.1.14, which requires, an emergency diesel generator to operate loaded for a minimum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Because this violation was of very low safety significance (Green) and was entered into the licensees corrective action program as Notification 50567942, it is being treated as a non-cited violation consistent with Section 2.3.2.a of the NRCs Enforcement Policy:
NCV 05000323/2014005-01, Failure to Provide Adequate Design Review of EDG 2-3.
.2 (Closed) LER 05000275/1-2014-001-00:
Technical Specification 3.4.3, Reactor Coolant System Pressure Limit Violation During Vacuum Refill Due to Human Error On January 28, 2014, Pacific Gas and Electric documented in Notification 50606432 the potential of generic implications from Regulatory Operating Experience at another station to Diablo Canyon Power Plant. The operating experience described another nuclear power plants failure to comply with technical specifications reactor coolant system (RCS) pressure and temperature limits. This failure was associated with reducing RCS pressure below zero pounds per square inch gauge (PSIG) to support a cold shutdown activity. Since 2001, this activity was also used by PG&E operators following refueling outages and after a design change to the plant allowed implementation of OP A-2:IX, Reactor Vessel-Vacuum Refill of the RCS. This change reduced worker dose and improved primary water chemistry following refueling outages.
On March 31, 2014, the licensee submitted a licensee event report on this event for an apparent failure to comply with RCS Pressure and Temperature Limits when RCS pressure was below zero pounds per square inch gauge (psig) during RCS vacuum fill operations. The licensee event report identified Technical Specifications (TS) 3.4.3, RCS Pressure and Temperature Limits, states RCS pressure, RCS temperature, and RCS heat up and cooldown rate shall be maintained within the limits specified in the Pressure Temperature Limits Report (PTLR).
The PTLR contains pressure/temperature administrative limits includes curves for heat up, cooldown, leak testing and maximum rate of RCS temperature. The licensee verified the refill activity was bounded by the applicable TS 3.4.3 limits and revised the PTLR curves to ensure pressure scale extended to a pressure value of 0.0 pounds per square inch absolute (psia) as the lower limit.
On December 29, 2014, the licensee documented in a letter to the NRC justification for cancelling Licensee Event Report (LER) 1-2014-001 based on in-depth evaluation, which concluded a violation of technical specifications, had not occurred. Using guidance in Section 5.1.2 of NUREG-1022, Revision 3, Event Reporting Guidelines 10 CFR 50.72 and 50.73, the inspectors reviewed the licensees evaluation and determined that the withdrawal of the LER was appropriate.
The specific documents reviewed during this inspection are listed in Attachment 1. This licensee event report is closed.
These activities constitute completion of two event follow-up samples, as defined in Inspection Procedure 71153.
4OA6 Meetings, Including Exit
Exit Meeting Summary
On March 18, 2015, the inspector conducted a telephonic exit meeting to present the results of the in-office inspection of changes to the licensees emergency plan and implementing procedures to Mr. B. Ashbrook, Acting Director, Nuclear Security and Emergency Services, and other members of the licensee staff. The licensee acknowledged the issues presented.
On April 9, 2015, the resident inspectors presented the inspection results to Mr. J. Welsch, Site Vice President, 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
- B. Allen, Vice President Nuclear Services
- B. Ashbrook, Acting Director, Nuclear Security and Emergency Services
- T. Baldwin, Director, Nuclear Site Services
- D. Evans, Director, Security & Emergency Services
- P. Gerfen, Director of Operation Services
- M. Ginn, Manager, Nuclear Emergency Planning
- E. Halpin, Sr. Vice President, Chief Nuclear Officer
- A. Heffner, NRC Interface, Regulatory Services
- J. Hinds, Director, Quality Verification
- T. Irving, Manager, Radiation Protection
- J. MacIntyre, Director of Equipment Reliability
- J. Morris, Senior Advising Engineer
- J. Nimick, Station Director
- A. Peck, Director, Nuclear Engineering
- L. Sewell, Nuclear Radiation Protection Engineer
- R. Simmons, Manager, Nuclear Maintenance
- P. Soenen, Manager, Nuclear Regulatory Services
- A. Warwick, Supervisor, Emergency Planning
- J. Welsch, Site Vice President
- M. Wright, Nuclear Engineering, Manager
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Opened and Closed
Failure to Provide Adequate Design Review of EDG 2-3
(Section 4OA3.1)
Closed
05000323/2-2013-004-00
LER
Technical Specification 3.8.1 Not Met Due to Failed Wire
Lug on Emergency Diesel Generator 2-3 (Section 4OA3.1)
05000323/2-2013-004-01
LER
Technical Specification 3.8.1 Not Met Due to Failed Wire
Lug on Emergency Diesel Generator 2-3 (Section 4OA3.1)
05000275/1-2014-001-00
LER
Technical Specification 3.4.3, Reactor Coolant System
Pressure Limit Violation During Vacuum Refill Due to Human
Error (Section 4OA3.2)
Section 1R01: Adverse Weather Protection
Procedures
Number
Title
Revision
OP O-28
Intake Management
CP M-16
Severe Weather
Section 1R04: Equipment Alignment
Procedures
Number
Title
Revision
OP E-5:1
Unit 1 Auxiliary Saltwater - Make Available
OP E-5:1
Unit 2 Auxiliary Saltwater - Make Available
OP J-6B:II-A
Diesel Generator 1-2 alignment Checklist
OP F-2:VI
CCW System Alignment Verification
OP E-5:I-a
ASW Alignment Verification
Notifications
50599631
50680934
50682009
50681899
50412958
50667855
50541667
Drawings
Number
Title
Revision
SISI Appendix I -
Figure 12
Seismically Induced System Interaction Target Location
Drawing, Units 1 & 2 Intake Structure
SISI Appendix 1-
Figure 13
Seismically Induced System Interaction Target Location
Drawing, Parking Lot 5, Elevation 85 foot
202
Starting Air Dryer System
2021
Turbo Charger Air Assist System -Sheet 4A
107714
OVID Unit 2 Component Cooling Water System
Section 1R05: Fire Protection
Procedures
Number
Title
Revision
TQ1.DC12
Fire Brigade and Emergency Response Training
Appendix 9.5H
FSAR Update
Inspection and Testing Requirements and Program
Administration
Notifications
50682433
A0597080
50642576
50623953
50675842
50693061
50693062
50695088
50695089
50695211
50695039
Drawings
Number
Title
Revision
TB-2
Unit 1, Fire Strategy: Turbine Building Buttress Elev. 85 &
104 foot
TB-3
Unit 1, Fire Drawing: Turbine Building Elev. 85 foot
TB-8
Unit 1, Fire Drawing: Turbine Building Elev 119 foot
TB-9
Unit 1, Fire Strategy: Turbine Building Elev 119 foot
PA-1
Pre Fire Plans Unit 1&2 Intake Structure
PA-2
Pre Fire Strategies Unit 1&2 intake Structure
AD4.ID3
SISIP Housekeeping Activities
RA-7& RA-15
Pre Fire Plans Unit 1&2 RCA 100-foot elevation
RA-8& RA-16
Pre Fire Strategies Unit 1&2 RCA 100-foot elevation
Other
Number
Title
Date
Fire Drill Guide
Building 201/202 Fire
March 25, 2014
Fire Drill Guide
25 480 V MCC 15 D&E Room Fire
March 26, 2015
PG&E Fire Team
Qualification
Status Transcripts and Reports for Crews A, B, and C March 16, 2015
Section 1R06: Flood Protection Measures
Procedures
Number
Title
Revision
STP M-70D
Inspection of Fire Barriers, Rated Enclosures, Credited
Cable Tray Fire Stops, and Equipment Hatches
TS1.ID16
Plant Doors
Notifications
50694326
50694460
Drawings
Number
Title
Date
515221 Sheet 2 Unit 1-Door Schedule, Operational Requirements for
Doors with Functional Important to Safety
February 20, 2015
515224 Sheet 2
Unit 2-Door Schedule, Operational Requirements for
Doors with Functional Important to Safety
March 26, 2014
Section 1R11: Licensed Operator Requalification Program and Licensed Operator
Performance
Procedures
Number
Title
Revision
AR PK12-17
Annunciator Response Turbine Supervision
CP M-4
OP K-2C
Fire Protection Network Operations
OP1.DC10
Conduct of Operations
OP1.DC37
Plant Logs
OP L-2
Hot Standby to Startup Mode
Other
Number
Title
Revision
Lesson Plan
R145S2
D/G 1-1 Run and Fire with LOAP
0A
Section 1R12: Maintenance Effectiveness
Procedure
Number
Title
Revision
MA1.ID17
Maintenance Rule Monitoring Program
Notifications
50681425
50681169
50664392
50664707
50681514
50681169
50664392
50684437
50683171
5068683
Section 1R13: Maintenance Risk Assessments and Emergent Work Control
Procedures
Number
Title
Revision
TP TO-15001
VCT H2 Regulator PCV-955 Repair or Replacement
OP J-6B:IX
Diesel Generator Extended On-Line Maintenance
OP O-36
Protected Equipment Postings
OP1.ID7
ODM Meeting
AD7.ID14
Risk Management Plan - De-energize 230 kV to Cold Wash 0
Notifications
50680272
50680273
50560735
50673779
50684437
50683171
Work Orders
60044387
64123393
64123397
Other
Number
Title
Date
DDP 1-24983
Design Change Package Evaluation-PSRC Meeting
July 16, 2014
Section 1R15: Operability Determinations and Functionality Assessments
Procedures
Number
Title
Revision
CAP O-6
Adding Chemicals to Closed Water Systems
AR PK17-08
Annunciator Response Diesel 21 Cooling System
OP1.ID7
ODM Meeting
Notifications
50680660
50675134
50679028
50673779
50684437
50683171
50689586
50691242
Section 1R18: Plant Modifications
Procedures
Number
Title
Revision
CF4.ID7
Temporary Alterations
CF4.ID7
Modification Implementation
28A
STP M-74
Auto Start of the ASW Pumps on Low Pressure
Notifications
50664540
60073263
60073264
60073260
60073261
50686883
Other
Number
Title
Date
Design Change Package
Change Containment Fan Cooler Unit Timer
Relay
July 17, 2014
Section 1R19: Post-Maintenance Testing
Procedures
NUMBER
TITLE
Revision
STP M-9A2
Routine EDG 1-2 Surveillance Testing
STP P-AFW-21
Routine Surveillance Test of Turbine-Driven Auxiliary
Feedwater Pump 2-1
MP E-
60.1DEG13
Circuit Function Test EDG 13 Protection Scheme
Notifications
50681043
50681013
50681194
50681169
50681581
50682674
50687363
Work Orders
60075030
64113901
64128239
64123393
64123397
Section 1R22: Surveillance Testing
Procedures
Number
Title
Revision
STP R-10C
Reactor Coolant System Water Inventory Balance
STP 1-1B
Routine Daily Checks Required by Licenses
104
STP V-3P5
Exercising Valves LCV-106,107,108, and 109 Auxiliary
Feedwater Pump Discharge
STP V-3R6
Exercising Steam Supply Valves to AFW
STP V-3
Exercising Safety Related Valves-General Procedure
STP G-15B
Determination of Valve Strokes Times with Equipment
Timers
STP I-37-N31.B
Source Range N-31 Channel Calibration
STP M-74
Auto Start of the ASW Pumps on Low Pressure
MP E-
60.1DEG13
Circuit Function Test EDG 13 Protection Scheme
Notifications
50686089
50683048
50572355
50683131
50369393
50686653
68032209
50686883
64123393
64123397
Work Orders
64124937
64073742
64073689
64067503
64066654
60033586
600642741
1EP4: Emergency Action Level and Emergency Plan Changes
Procedures
Number
Title
Revision
Section 8, Maintaining Emergency Preparedness
Revision 4.12
Section 5, Organizational Control of Emergencies
Revision 4.15
Appendix F, ERO On-Shift Staffing Analysis Report
Revision 4.01
Section 1, Definitions and Abbreviations
Revision 4.07
Section 2, Scope and Applicability
Revision 4.04
Section 4, Emergency Conditions
Revision 4.14
Section 6, Emergency Measures
Revision 4.14
Section 7, Emergency Facilities and Equipment
Revision 4.19
Appendix A, Procedures
Revision 4.06
Appendix G, Protective Action Recommendation (PAR)
Strategy Bases
Revision 4.00
EP G-3
Emergency Notifications of Off-Site Agencies
Revision 57
EP RB-10
Protective Action Recommendations
Revision 18
EP RB-16
Operating Instructions for the EARS Computer Program
Revision 11
Documents: 50.54(q) Effectiveness Evaluation Form
Number
Title
2014-075
Appendix G
2014-078
E-Plan App A Rev 4.06
2014-090
E-Plan Sec 7 Rev 4.19
2014-092
mile radius
2014-093
Emergency Kits
2014-094
E-Plan Sec 8 Rev 4.12
2014-095
Vehicles
2014-096
Plan Section 8
2014-097
Appendix F
2014-098
RM-87 Range
2014-099
E-Plan Sec 1 Rev 4.07
2014-100
2014-104
E-Plan Sec 2 Rev 4.04
2014-110
E-Plan Sec 5 Rev 4.15
2014-116
KI Range
2014-117
EARS/MIDAS
2014-118
Manual Calcs
2014-121
E-Plan Sec 6 Rev 4.14
2014-122
E-Plan Sec 4 Rev 4.14
2014-129
EP RB-10
2014-130
EP G-3
2014-134
Section 1EP6: Drill Evaluation
Procedures
Number
Title
Revision
CP M-4
OP AP-1
Excessive Reactor Coolant Leakage
EOP ECA-1.1
Loss of Emergency Coolant Recirculation
EP G-4
Emergency Planning Implementing Procedure: Assembly
and Accountability
EP G-2
Interim Emergency Response Organization
ECTL3415
ECTL3415
Section 4OA3: Follow-up of Events and Notices of Enforcement Discretion
Procedures
Number
Title
Revision
OM4.ID3
Operating Experience Program
MA1.DC54
Conduct of Maintenance
MP E-57.14A
PI and Hipot Testing
Documents
Title
Description
Date
Perry Nuclear Power
Plant-Revised Non-Cited
Violation
NRC PI&R Inspection Report 05000440/2013007 (ML14246A151)
September 3, 2014
PG&E Letter DCL-14-121
Cancellation of Licensee Event Report 1-
2014-001 (ML14363A266)
December 29, 2014
Pressure Temperature
Limits Report (PTLR-1)
PTLR-1 Revision 14, 10 CFR 50.59 screen
February 4, 2014
Notifications
50363143
50383335
50567942
50568251
50568303
50573110
50652439
50659319
Work Orders
64021820
64045607
Action Requests
A0172916
A0185742
A0186057
Miscellaneous
Number
Title
Revision
N0001405
Nonconformance Report - Diesel Generator
SDP13-02
Risk Significance of DEG 2-3 Trip after 22 Hour Run
0