IR 05000440/2018040
| ML18086B212 | |
| Person / Time | |
|---|---|
| Site: | Perry  |
| Issue date: | 03/27/2018 |
| From: | Billy Dickson NRC/RGN-III/DRP/B5 |
| To: | Hamilton D FirstEnergy Nuclear Operating Co |
| References | |
| EA-17-043 IR 2018040 | |
| Download: ML18086B212 (17) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION rch 27, 2018
SUBJECT:
PERRY NUCLEAR POWER PLANTNRC SUPPLEMENTAL INSPECTION REPORT 05000440/2018040 AND ASSESSMENT FOLLOW-UP LETTER
Dear Mr. Hamilton:
The U.S. Nuclear Regulatory Commission (NRC) completed a supplemental inspection using Inspection Procedure 95001, Supplemental Inspection Response To Action Matrix Column 2 Inputs, at your Perry Nuclear Power Plant. On February 15, 2018, the NRC discussed the results of this inspection and the implementation of your corrective actions with Mr. Frank Payne and other members of your staff in an exit Meeting. On February 16, 2018, the NRC discussed the causes and your corrective actions identified as a result of the WHITE finding, and the criteria required for returning to the Licensee Response Column of the Action Matrix with Mr. Frank Payne in a Regulatory Performance Meeting. The results of this inspection are documented in the enclosed report.
By letter dated August 24, 2017, (ADAMS ML17236A187), the U.S. Nuclear Regulatory Commission (NRC) informed you that as a result of a White (low-to-moderate safety significance) finding in the Mitigating Systems Cornerstone that the NRC assessed Perry Nuclear Power Plant performance to be in the Regulatory Response Column of the Reactor Oversight Process (ROP) Action Matrix, effective the second quarter of 2017. In the same letter, the NRC informed you of our intent to perform a supplemental inspection using Inspection Procedure 95001 upon notification of your readiness for the inspection. By letter dated October 31, 2017, we were notified by your staff that you were ready for the NRC to conduct our supplemental inspection to review the actions taken to address the White finding.
The NRC performed this inspection to review your stations actions in response to a White finding in the Mitigating System cornerstone which was documented in NRC Inspection Report 05000440/2017009 (ML17156A750). The finding involved the failure to evaluate the effects of voltage suppression diode failure on the Emergency Diesel Generator (EDG) control circuit, which was a component subject to the requirements of Title 10 of the Code of Federal Regulations (CFR) Part 50, Appendix B. Specifically, FirstEnergy failed to consider the effect of a shorted diode on the control circuitry of the EDG, and, as a result, failed to recognize that installation of voltage suppression diodes across control relays, with no mitigation for diode failure, was not suitable for the EDG control circuit. This introduction of new components (diodes) into the control circuitry resulted in the eventual failure of the EDG control circuit, thereby rendering the EDG inoperable and unable to start.
The NRC determined that the completed or planned corrective actions were sufficient to address the performance issue that led to the White finding previously described and were prioritized commensurate with the safety significance of the issue. In addition, the NRC determined that the root cause evaluation was conducted to a level of detail commensurate with the significance of the problem and reached reasonable conclusions as to the root and contributing causes of the event.
No finding or violations were documented.
After reviewing Perry Nuclear Power Plants performance in addressing the White finding subject of this Inspection Procedure 95001, the NRC concluded your actions met the objectives of the inspection. Therefore, in accordance with the guidance in Inspection Manual Chapter (IMC) 0305, Operating Reactor Assessment Program, the White finding will only be considered in assessing plant performance for a total of four quarters. As a result, the NRC determined the performance at Perry Nuclear Power Plant to be in the Licensee Response Column of the ROP Action Matrix as of April 1, 2018.
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/
Billy Dickson, Chief Branch 5 Division of Reactor Projects Docket No. 50-440 License No. NPF-58 Enclosure:
Inspection Report 05000440/2018040 cc: Distribution via LISTSERV
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring licensees performance by conducting a supplemental inspection at Perry Nuclear Power Plant in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information. NRC and self-revealed findings, violations, and additional items are summarized in the table below.
List of Findings and Violations No findings or violations were identified.
Additional Tracking Items Type Issue Number Title Report Status Section NOV 05000440/2017009-01 Division 2 Diesel Generator 95001 Closed Failure to Start due to a Failed Diode in the 125 VDC Control Power Circuit
TABLE OF CONTENTS
INSPECTION SCOPES
OTHER ACTIVITIES
TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL
INSPECTION RESULTS
............................................................................................................
EXIT MEETINGS AND DEBRIEFS
............................................................................................ 13
DOCUMENTS REVIEWED
......................................................................................................... 13
INSPECTION SCOPES
Inspections were conducted using the appropriate portions of the inspection procedure (IPs) in
effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with
their attached revision histories are located on the public website at http://www.nrc.gov/reading-
rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared
complete when the IP requirements most appropriate to the inspection activity were met
consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection
Program - Operations Phase. The inspectors reviewed selected procedures and records,
observed activities, and interviewed personnel to assess licensee performance and compliance
with Commission rules and regulations, license conditions, site procedures, and standards.
OTHER ACTIVITIESTEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL
95001 - Supplemental Inspection Response to Action Matrix Column 2 Inputs
Perry Nuclear Power Plant entered the Regulatory Response column of NRCs Action Matrix
in the 2nd quarter of 2017 due to a White (low-to-moderate safety significance) inspection
finding,05000440/2017009-01, in the Mitigating Systems Cornerstone. The finding was
associated with the stations failure to evaluate the effects of voltage suppression diode failure
on the Emergency Diesel Generator (EDG) control circuit. The finding was characterized as
having White safety significance based on the results of a risk assessment performed by a
region-based Senior Reactor Analyst. This issue was documented in NRC Inspection
Reports (IRs) 05000440/2017009 and 05000440/2017010.
By letter dated November 3, 2017, the licensee notified the NRC that it had completed its
evaluation of the circumstances surrounding the degraded performance and were ready for the
NRC to assess the evaluation and subsequent corrective actions. In preparation for the
inspection, the licensee performed Root Cause Evaluation (RCE), PRA Evaluation Associated
with the Div. 2 EDG MSPI Failure (CR 2016-14456) Indicates a Preliminary Level of
Significance that Warrants a Root Cause Evaluation, Revision 2, dated October 9, 2017. It
identified weaknesses that existed in various organizations which allowed for a risk-significant
finding, and to determine the organizational attributes that resulted in the White finding.
The affected diesel generators are identified as the Standby Diesel Generator and Emergency
Diesel Generator in this reports reference documents and are used interchangeably. This
report uses Emergency Diesel Generator for consistency.
The inspectors reviewed the licensees root causes, contributing causes, extent of condition,
and extent of cause determinations. The inspectors assessed whether the licensees corrective
actions to address the root and contributing causes were sufficient to prevent recurrence. The
highlights of the performance review and NRCs assessment are documented below.
Evaluation of Inspection Requirements
(1) Problem Identification
a) [Describe who identified the issue and under what conditions the issue was
identified.]
Root cause CR 2016-14456 evaluation concluded that the diode failure (shorted) for
relay R10BB, 1R43Q0003B, which resulted in loss of the 125 Volts, Direct
Current, (VDC) control power to the Division 2 EDG, was self-revealed on
November 6, 2016, while performing surveillance test PTI-R43-P0006B, Division 2
Diesel Generator Pneumatic Logic Board Functional Check. Operators received
various unexpected alarms when a jumper was installed to simulate an
emergency (auto) start as part of the surveillance test.
b) [Describe how long the issue existed and prior opportunities for identification.]
Root cause CR 2016-14456 evaluation concluded this issue existed when the
suppression diodes were installed in the control circuitry of the Division 2 EDG on
April 21, 2007.
The licensee identified that an opportunity was missed after the diode on relay R11
failed on May 6, 2016. On April 21, 2007, the licensee initiated and discussed in
CR-2016-06450 that the new Allen Brandley relays R11A, R10BB, RSS, K4, and
associated diodes, were installed on the Division 2 EDG by ECP 04-0049. This
relay was energized on May 06, 2016 during a monthly Surveillance test. The diode
in parallel with the relay R11A failed causing alarms, abnormal indications, and
required operator action to shutdown the DIV2 EDG. The diode was replaced based
on CR-2016-06450 on May 06, 2016. The licensee did not then consider the
effects of a shorted diode, for other diodes in the system and other EDGs.
c) [Describe the plant-specific risk consequences, as applicable, and compliance
concerns associated with the issue.]
The licensee did not document a Probabilistic Risk Assessment (PRA) evaluation for
this condition. The Licensee discussed the NRC risk assessment that concluded the
safety significance for this issue as White (low-to-moderate) based on the
Division 2 EDG not operable and unable to perform its emergency start function from
April 2, 2015, when it passes a surveillance test, until November 8, 2016 when the
emergency start diode was replaced after failure and the Division 2 EDG was
returned to service. Because the licensee was not aware of the Div 2 EDGs
inoperability during the units operation cycle, the required actions of TS 3.8.1.F.1
and 3.8.1.F.2 were not followed. The evaluation also recognized this determination
resulted in being placed in the Regulatory Response Column of the NRCs Reactor
Oversight Process (ROP) Action Matrix.
(2) Root Cause, Extent-of-Condition, and Extent-of-Cause Evaluation
a) [Describe systematic methodology used to identify the root and contributing causes.]
The licensee assigned a multi-disciplined team to perform a Root Cause Evaluation
to identify the root and contributing causes of the EDG inoperability and the inability
to start. In its root cause analysis, the licensee used the following processes to
identify the root and contributing causes:
- Data gathering through interviews and document review;
- Event and Causal Factor Charting;
- Internal and External Laboratory Analysis;
- Equipment Apparent Cause Evaluation (EACE);
- Latent Organization Weakness Analysis;
- Performance Improvement International Failure Modes Analysis; and
- MORT Analysis.
The licensee used the above processes to evaluate equipment and human
performance issues associated with the event. The processes used were systematic
processes governed by and implemented in accordance with the licensees
procedures. The processes were used to ensure the information and circumstances
surrounding the problem were understood. The results of these processes revealed
two root causes and one contributing cause. The initial root cause evaluation
attributed the failure to a manufacturing defect in the diode with a contributing cause
related to engineering design practices. The Notice of Violation (NOV) was issued in
August of 2017 for failing to recognize that installation of voltage suppression diodes
across control relays, with no mitigation for diode failure, was not suitable for the
EDG control circuit. This introduction of new components (diodes) into the control
circuitry resulted in the eventual failure of the EDG control circuit, thereby rendering
the EDG inoperable and unable to start. After the NOV was issued, Revision 2 of the
Root Cause Evaluation identified using diodes as a common design practice as a
second root cause. This aligned closer with the NOV. The licensee also determined
that discrepancies with vendor acceptance criteria used during initial dedication was
a contributing cause.
b) [Describe level of detail of detail used in the root cause evaluation and indicate
whether it was commensurate with the significance of the problem.]
In its root cause analysis, the licensee classified the event as a significant condition
adverse to quality and applied thorough processes and methodologies to identify the
root and contributing causes associated with the licensees failure to evaluate the
effects of voltage suppression diode failure on the EDG control circuit. The analysis
performed in the root cause were of sufficient detail commensurate with the
significance of the problem. The licensees root cause evaluation included a timeline
of events. The licensee conducted interviews, and performed work history and
corrective action document reviews to capture the issues leading up to the event.
The root cause evaluation resulted in corrective actions that promptly addressed the
design issues with the use of the diodes in the EDG control circuitry that would
prevent recurrence. The engineering deficiency that was the basis of the NOV
occurred in 2005 and the root cause evaluation addressed engineering issues and
performance since then to characterize current behavior and develop corrective
actions.
c) [Describe prior occurrences and operating experience considered during the root
cause evaluation.]
The licensee included an evaluation of internal and external Operating
Experience (OE) for issues with issues related to the loss of control power resulting
from failed, shorted diodes. The licensee found that failures of diodes used to
suppress the inductive kickback of DC coils are not common at Perry nor within
the FENOC fleet.
Review of the external operating experience from INPO and NRC Websites was also
conducted that revealed seven issues related to diode failures. Three of these
occurred prior to completion of the engineering change package in 2005 that
subsequently installed the suppression diodes in the EDG control circuit. While
several of these events included failed, shorted diodes, none of the applications were
for suppression diodes. One event at Seabrook in 2003, OE 16764, concluded the
failed diodes were from manufacturing defects. At the time the licensees initial
screening of this OE did not identify any specific diode issues that would likely have
resulted in the corrective actions necessary to address the issue identified in Root
Cause (CR) 2016-14456.
The inspectors did identify one issue at Cooper, OE 214246, concerning the failure
of a blocking diodes in the transient suppression circuit of the EDG was not included
in root cause CR 2016-14456. The licensee reviewed this OE and concluded it was
missed during the external OE review. The licensee wrote CR 05-02410 that
determined the inclusion of this OE would not have changed the conclusion in the
root cause report.
d) [Describe the extent of condition and the extent of cause evaluations performed.]
Extent of Condition is defined in NRC Inspection Manual 95001 as the extent to
which the actual condition exists with other plant processes, equipment, or human
performance. The licensee determined there were two conditions of concern.
The first condition was that suppression (flyback) diodes were installed in
class 1E 125VDC circuitry whose failure could go undetected for an extended period
of time. To evaluate this equipment condition, the licensee identified the extent to
where the same component is used in the same or similar applications. In addition,
the licensee identified whether similar components existed in same or similar
applications. A review of Perry stock codes was performed to see where Allen
Bradley 199-FSMZ-1 flyback diodes were installed in the plant. The review
identified that these diodes were only utilized on each of the Division 1 and 2 EDGs
across relays R11A, R10BB, RSS, and K4. These diodes were all installed as part
of the ECP 04-0049 which upgraded the speed control governing system from a
Woodward EGA/EGB-35C to a Woodward2301A/EGB-35P for the Division 1 and 2
EDGs. All eight of these diodes have since been removed by the implementation of
ECP 16-0348 in December 2016. There was no other location identified in the plant
where this particular diode is used.
Lab testing of the Division 1 R10BB Relay (the same relay that failed in the
Division 2) after removal provided assurance that the relay surge suppressor would
have performed had an EDG Division 1 Auto-Start occurred during the time it had
been installed.
The licensee also identified systems and their respective drawings that were likely to
include 1E components. It was determined that there were 13 drawings warranting
further review by the Responsible System Engineers to identify diodes/relays that are
not tested at least quarterly. This review found there were four systems as follows:
Reactor Recirculation System (2 total)
Residual Heat Removal System (52 total)
Division 3 HPCS Diesel Generator (4 total)
Reactor Core Isolation Cooling System (18 total)
These components were tested and found satisfactory through continuity tests or
performance of surveillance tests. The diodes in these systems were installed in
accordance with industry and vendor design practice and not Perry engineering
modifications. Their reliability has been established over the many numbers of years
of operating experience. The consequences of failures of any of the diodes were
evaluated by engineering and operations and found to be no different than a failure
of any part in the system and designed to be identified during the normal scheduled
surveillances.
The second condition defined by the licensee was associated with Plant Processes
and Human Performance. Specifically, related to the NRC performance deficiency
cited in the NOV as the failure to evaluate the effects of voltage suppression diode
failure on the EDG control circuit. The licensee reviewed the corrective action
program to identify issues that may have existed because the failure effects of
components added/changed by the modification process were not properly evaluated
resulting in a system/component failure. The review identified evidence that the
failure effects of components added/changed by the modification process at Perry
were not properly evaluated and resulted in a system/component failure. Seven
issues were identified in the last ten years, however none within the last three years.
The licensee created CA 2016-14456-015 to perform a self-assessment of the
safety related design modifications issued at Perry since 2005. This assessment will
verify that proper failure modes and effects have been considered for the new
components added to MSPI systems. This corrective action will address the
potential existence of latent design deficiencies that have not yet resulted in an
equipment failure. This corrective action completion date is scheduled for
March 30, 2018.
The extent of cause (EOC) evaluation determines the extent to which the causes of
an identified problem have impacted other plant processes, equipment, or human
performance.
The Root Cause Evaluation CR 2016-14456, identified two root causes and one
contributing cause including:
Root Cause: Using diodes as a common design practice
Root Cause: Manufacturing Defect
Contributing Cause: Discrepancies with vendor (ESI) acceptance criteria used
during initial dedication testing.
The inspectors only reviewed the extent of the root cause related to using diodes as
a common design practice. This evaluation is similar to the extent of condition
evaluation associated with Plant Processes and Human Performance discussed
above. While the other root cause associated with a manufacturing defect was
useful to the licensee, the inspectors determined that absent the performance
deficiency cited in the NOV, the failure of the diode in the R10BB relay due to the
manufacturing defect would not have had the same consequences.
To evaluate the extent of using diodes as a common design practice, the licensee
reviewed safety-related design changes implemented since 2005 identify other
locations where surge suppression devices were installed in the plant that may not
be needed and hence may have created an unnecessary failure mechanism. To
identify if other types of incorrect mindset or misapplication of common design
standards existed within engineering that have affected the quality of engineering
changes, the Perry site performance indicators associated with engineering changes
were reviewed.
As a result of the evaluations, the licensee did not identify any other applications
where diodes were not needed. Also, an adverse trend in engineering product
quality identified in the Engineering indicators was closed in the first half of 2016
based on a sustained improvement in engineering product/ECP quality.
e) [Indicate whether safety culture components were appropriate considered during the
root cause, extent of condition, and extent of cause evaluations performed.]
Safety Culture components were adequately addressed in the root cause by
evaluation of the causal factors against the NRC safety culture aspects and the
categories for INPO traits of a healthy safety culture. The licensee identified no
safety culture aspects as significant contributors to the event. No cross-cutting issue
was assigned by the NRC in the NOV since the performance deficiency associated
with this finding occurred more than three years ago; therefore, it did not reflect
current licensee performance.
The root cause did identify related cross cutting aspects that could be related to the
design aspects of the NOVs performance deficiency. Specific aspects identified
were, (1) Avoid Complacency, (2) Consistent Process and, (3) Conservative Bias.
Corrective actions CA-2016-14456-02 and CA-2016-14456-013 were initiated to
address these safety culture aspects. The first action provided training and lessons
learned to all engineering staff that emphasized minimizing installation of
components that are not needed. The second action was to discuss the lessons
learned from this issue to all supervisory staff. Both of these actions were
completed.
(3) Corrective Actions
a) [Describe corrective actions taken, planned, or why unnecessary for each root and
contributing cause. Specifically identify those corrective action taken or planned to
prevent recurrence. Planned corrective actions to prevent recurrence will be
inspected using IP 71152.]
The Root Cause Evaluation in CR 2016-14456, identified two root causes and one
contributing cause including:
Root Cause: Using diodes as a common design practice
Root Cause: Manufacturing Defect
Contributing Cause: Discrepancies with vendor acceptance criteria used during
initial dedication testing.
The NOV cited the failure to consider the effect of a shorted diode on the control
circuitry of the Division 2 EDG, and, as a result, the failure to recognize that
installation of voltage suppression diodes across control relays, with no mitigation for
diode failure, was not suitable for the EDG control circuit and was a violation
of 10 CFR, Part 50, Appendix B, Criterion III, Design Control.
Corrective actions that addressed the NOV were conducted under CR 2016-13183.
These actions included an evaluation by engineering that all the suppression diodes
installed in the control circuitry were not needed and therefore could be removed
permanently in ECP 16-0348-004. Removal of the all the suppression diodes
was completed for the Division 1 EDG by Work Order (WO) 200701159 on
December 17, 2016 and for the Division 2 EDG by WO 200701164 on
December 22, 2016. These actions were completed prior to issuance of the NOV.
The actions above addressed the licensee root cause of using diodes as a common
design practice. To further address this root cause the licensee initiated corrective
actions that performed or will perform reviews of engineering packages since 2006 to
determine current engineering practices and standards. Additional corrective actions
included training for all design engineers on this issue, ensuring this issue is part of
the mentoring program discussions for all new engineers, discussions of this issue
with all plant supervisors, and finally revisions to the EDG systems training plan.
To address the other licensee root cause of a manufacturing defect, corrective
actions included the removal of the diodes as discussed above. In addition, another
corrective action was to complete or verify complete the 10 CFR 21 Requirements
(internally or externally) of the defective diodes.
The licensee implemented an action for the contributing cause for the discrepancies
with vendor acceptance criteria used during initial dedication testing. The diode
supplier revised the dedication test plan to change the acceptance criteria for the
reverse bias testing of diodes from 500 micro amps leakage current to 5 micro amps.
b) [Describe the prioritization of each corrective action.]
Corrective actions were assigned a priority in accordance with procedure
NOBP-LP-2011, Root Cause Analysis, based on safety precedence. Priorities
included:
1. Design Hazard;
2. Safety Devices;
3. Safety Warnings;
4. Procedures;
5. Training/Awareness; and
6. Notify Management of Risk and Accept without Action.
c) [Describe the schedule established for implementing and completing each corrective
action.]
The Root Cause Evaluation contains the schedule for implementing the Corrective
Actions. Corrective actions to address the performance deficiency in the NOV were
completed in December 2016 when the suppression diodes were removed from the
control circuit relays in both the Division 1 and Division 2 EDGs. Most of the other
corrective actions were completed in 2017. The only corrective action not completed
by the time the 95001 inspection occurred was to perform a self-assessment of the
attached list of safety related and/or augmented quality design change packages
issued at the Perry Plant since 2005 discussed in 1 d) above.
d) [Describe the quantitative or qualitative measures of success that have been
developed for determining the effectiveness of the corrective actions to prevent
recurrence.]
The root cause evaluation contains several measures for determining the
effectiveness of the planned and completed corrective actions. Specifically:
1- Effectiveness Review (ER) 2016-14456-1, to be completed by
January 31, 2019, is to verify that between July 1, 2017 and January 1, 2019, no
new component failures have occurred in the 125 VDC control circuitry of the
Division 1 and 2 EDGs that are attributed to the removal of the diodes.
2- Effectiveness Review (ER) 2016-14456-2, to be completed by
September 1, 2019, is to perform a review of all safety related/augmented quality
design change ECPs issued between July 1, 2017 and July 1, 2019 that involve
electrical and/or instrumentation and control changes. For each ECP, the plant
will verify that suppression diodes were properly sized, a failure modes and
effects analysis or equivalent was completed, and it did not add unnecessary
components. New condition reports will be generated if these criteria were not
met.
e) [Indicate which corrective actions taken or planned adequately address the Notice of
Violation (NOV) as applicable.]
The NOV cited the failure to consider the effect of a shorted diode on the control
circuitry of the Division 2 EDG, and, as a result, the failure to recognize that
installation of voltage suppression diodes across control relays, with no mitigation for
diode failure, was not suitable for the EDG control circuit and was a violation
of 10 CFR, Part 50, Appendix B, Criterion III, Design Control.
Corrective actions that addressed the NOV were conducted under CR-2016-13183.
These actions included an evaluation by engineering that all the suppression diodes
installed in the control circuitry were not needed and could be removed permanently
in ECP 16-0348-004. Removal of the all the suppression diodes was completed
for the Division 1 EDG by Work Order (WO) 200701159 completed on
December 17, 2016 and for the Division 2 EDG by WO 200701164 completed on
December 22, 2016. These actions were completed prior to issuance of the NOV.
(4) Evaluation of IMC 0305 Criteria for Treatment of Old Design Issues. The licensee did
not request credit for self-identification of an old design issue; therefore, the risk-
significant issue was not evaluated against the IMC 0305 criteria for treatment of an old
design issue.
INSPECTION RESULTS
95001 - Supplemental Inspection Response to Action Matrix Column 2 Inputs
Observation IP 95001
Assessment of licensees evaluation and corrective actions.
The NRC determined that completed or planned corrective actions were sufficient to address
the performance issue that led to the White finding previously described and were prioritized
commensurate with the safety significance of the issue. In addition, the NRC determined that
the root cause evaluation was conducted to a level of detail commensurate with the
significance of the problem and reached reasonable conclusions as to the root and
contributing causes of the event.
The inspectors did observe that some of the corrective actions completed prior to the
issuance of the NOV were not revised or changed to ensure they addressed the performance
deficiency cited in the NOV. An example included the action to provide lessons learned to the
engineering department on the results of this root cause investigation. The inspectors found
the focus to be on the causal factors associated with the development of ECP 04-0049.
Specifically: 1. Need to perform testing during design development to validate proper sizing of
diodes 2. Minimizing the installation of components that are not required for the modification
to minimize probability of equipment failures. The inspectors noted this training had minimal
discussion on the failure to consider the effects of a shorted diode and was not a focus of the
training. The inspectors considered this action would have better addressed the performance
deficiency of the NOV if it would have been revised with this emphasis.
After reviewing Perry Nuclear Power Plants performance in addressing the White finding
subject of this Inspection Procedure 95001, Supplemental Inspection Response To Action
Matrix Column 2 Inputs, the NRC concluded actions taken by Perry Nuclear Power Plant met
the objectives of the inspection. Therefore, violation 05000440/2017009-01 is closed.
No findings or violations were identified.
EXIT MEETINGS AND DEBRIEFS
The inspectors confirmed that proprietary information was controlled to protect from public
disclosure. No proprietary information was documented in this report.
- On February 15, 2018, the inspectors presented the Supplemental Procedure 95001
inspection results to Mr. Frank Payne, and other members of the licensee staff.
- On February 15, 2018, the NRC discussed the performance of the Perry Nuclear Power
Plant in accordance with IMC 0305, Section 10.01. during a regulatory performance
meeting. The meeting was attended by the Mr. Billy Dickson, Chief, Branch 5 and Mr. Frank
Payne, Plant General Manager, and other senior licensee staff. The NRC and licensee
discussed the issues related to the WHITE finding resulted in Perry Nuclear Power Plant
remaining in the Regulatory Response Column of the Action Matrix.
DOCUMENTS REVIEWED
95001 - Supplemental Inspection Response to Action Matrix Column 2 Inputs
Condition Reports
- CR-2016-13183; During performance of PTI-R43-P0006B CB-1, CB-2, CB-3, CB-4 DC
Breakers Trip when loaded (superseded by root cause evaluation CR-2016-14456)
- CR-2016-14251; Additional vulnerabilities identified in surge suppression diode on the DIV 1
and DIV 2 Diesel Generators
- CR-2016-14456; PRA Evaluation Associated with Div 2 EDG MSPI Failure (CR-2016-13183)
Indicates a Preliminary Level of Significance that Warrants a Root Cause Evaluation
- CR-2017-05709; 2017 Pre-NRC PI&R Assessment does not meet Smart Criteria
- CR-2017-06396; NRC Apparent Violation- Unsuitable Application of Surge Suppression
Diodes in Standby Diesel Generator Control Power Circuitry
- CR-2018-00268; Evaluation of violation 05000400/2017009-01 "Unsuitable Application of
Surge Suppression Diodes in Standby Diesel Generator Control Power Circuitry"
Condition Reports Generated During Inspection
- CR-2018-01316; NRC 95001 Inspection; OE Review for CR-2016-14456
- CR-2018-01335; NRC 95001 Inspection; Training Needs Analysis for Root
Cause 2016-14456
Procedures
- NOBP-LP-2011; Root Cause Analysis; Revision 22
- NOBP-ER-3017; Selection and Devlopment of Engineering Mentors; Revision 00
Others
- ECP 16-0348-004; Modify Div. 2 Diesel Generator control circuitry for relay flyback diode
failure; dated December 14, 2016
- Equipment Apparent Cause Evaluation Template (EACE) Diode Failure on Relay R10BB;
December 2, 2016
- Failure Analysis Report CF16-060; BETA Laboratory Services Section; Diode, Surge
Suppressor; November 11, 2016
- Design Basis Assessment Report- Second Half 2017
- E-Mail from
- Job Performance Requirement, JPR 1.1; Engineering Change, Preparation, Approval,
Turnover and Closeout, July 17, 2017
14