IR 05000237/2016009
| ML16217A194 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 08/04/2016 |
| From: | Jeffers M NRC/RGN-III/DRS/EB2 |
| To: | Bryan Hanson Exelon Generation Co |
| References | |
| IR 2016009 | |
| Download: ML16217A194 (15) | |
Text
UNITED STATES ust 4, 2016
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - NRC PILOT DESIGN BASES INSPECTION (PROGRAMS) INSPECTION REPORT 05000237/2016009; 05000249/2016009
Dear Mr. Hanson:
On July 1, 2016, the U.S. Nuclear Regulatory Commission (NRC) completed the team portion of the pilot Design Bases Inspection at your Dresden Nuclear Power Station, Units 2 and 3. The enclosed report documents the results of this inspection, which were discussed on July 1, 2016, with Mr. J. Washko, and other members of your staff.
Based on the results of this inspection, the NRC inspectors identified one finding of very-low safety significance (Green) in this report. The finding did not involve a violation of NRC requirements.
In accordance with Title 10 of the Code of Federal Regulations (10 CFR) 2.390, Public Inspections, Exemptions, Requests for Withholding, of the NRC's "Rules of Practice," 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/
Mark T. Jeffers, Chief Engineering Branch 2 Division of Reactor Safety Docket Nos. 50-237, 50-249 License Nos. DPR-19; DPR-25
Enclosure:
IR 05000237/2016009; 05000249/2016009
REGION III==
Docket Nos. 50-237, 50-249 License Nos. DPR-19; DPR-25 Report No: 05000237/2016009; 05000249/2016009 Licensee: Exelon Generation Company, LLC Facility: Dresden Nuclear Power Station, Units 2 and 3 Location: Morris, IL Dates: June 27 - July 1, 2016 Inspectors: A. Dunlop, Senior Reactor Inspector, Lead S. Sheldon, Senior Project Engineer G. Hausman, Senior Reactor Inspector Observers: M. Domke, Reactor Inspector Approved by: M. Jeffers, Chief Engineering Branch 2 Division of Reactor Safety Enclosure
SUMMARY
Inspection Report 05000237/2016009; 05000249/2016009, 06/27/2016 - 07/01/2016;
Dresden Nuclear Power Station, Units 2 and 3; Pilot Design Bases Inspection (Programs).
The inspection was a 1-week onsite baseline inspection that focused on the implementation of the Environmental Qualification Program. The inspection was conducted by three regional engineering inspectors. One finding was identified by the inspectors. The significance of inspection findings are indicated by their color (i.e., greater than Green, or Green, White,
Yellow, Red) and determined using Inspection Manual Chapter 0609, Significance Determination Process, dated April 29, 2015. Cross-cutting aspects are determined using Inspection Manual Chapter 0310, Components Within the Cross Cutting Areas, dated December 4, 2014. The U.S. Nuclear Regulatory Commission's program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 5, dated February 201
NRC-Identified
and Self-Revealed Findings
Cornerstone: Mitigating Systems
- Green.
The inspectors identified a finding of very-low safety significance for the failure to perform a 24-month channel calibration of the Regulatory Guide 1.97 safety/relief valve acoustic monitoring system in accordance with the Technical Requirements Manual. Specifically, the licensee failed to perform a channel calibration, where the channel calibration shall encompass all devices in the channel required for channel operability and the channel functional test.
The performance deficiency was determined to be more-than-minor because the finding was associated with the Mitigating Systems cornerstone attribute of Procedure Quality and affected the cornerstones objective of ensuring the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the licensee failed to maintain the acoustic safety/relief valve position indicators instrumentation in accordance with the Technical Requirements Manual. The performance deficiency affected the design or qualification of a mitigating system, structure or component; however, the system, structure or component maintained its functionality based on successful completion of channel functionality checks. Since the system, structure or component remained functional, the inspectors screened the finding as having very low safety significance (Green). The inspectors did not identify a cross-cutting aspect associated with this finding because the finding was not representative of the licensees current performance. (Section 1R21.3b)
Licensee-Identified Violations
No findings were identified.
REPORT DETAILS
REACTOR SAFETY
Cornerstone: Mitigating Systems and Barrier Integrity
1R21 Design Bases Inspection (Programs)
.1 Introduction
This is a pilot inspection of a licensee program conducted per U.S. Nuclear Regulatory Commission (NRC) Inspection Procedure (IP) 71111.21N. The objective of the Design Bases Inspection is to gain reasonable assurance that structures, systems, and components (SSC) can adequately perform their design basis function. This includes reasonable assurance that electrical equipment important-to-safety for which a qualified life has been established can perform its safety functions without experiencing common cause failures before, during, and after applicable design basis events. This inspection will review the licensees implementation of the electrical equipment Environmental Qualification (EQ) Program, as required by their license, for maintaining the qualified status of equipment during the life of the plant. The inspection is intended to assess the programs effectiveness by sampling a limited number of components. This inspectable area verifies aspects of the Mitigating Systems and Barrier Integrity cornerstones for which there are no indicators to measure performance.
The inspectors assessed the implementation of the EQ program, established to meet the requirements of Title 10 of the Code of Federal Regulations, Part 50.49, Environmental Qualification of Electrical Equipment Important to Safety for Nuclear Power Plants. The scope of this rule included safety-related equipment relied upon to remain functional during and following design basis events, nonsafety-related equipment whose failure under postulated environmental conditions could prevent safety-related equipment from performing design functions, and certain post-accident monitoring equipment. The NRC originally verified plants EQ Program implementation through a series of onsite inspections from 1984 - 1989. The EQ Program at that time established measures to ensure components met the EQ rule through the 40-year operating license period.
Since that time, both units have renewed their operating licenses for an additional 20 years. Unit 2 entered its period of extended operation in 2009 and Unit 3 entered its period of extended operation in 2011.
Specific documents reviewed during the inspection are listed in the Attachment to the report.
.2 Inspection Sample Selection Process
The inspectors selected components for review using information provided by the licensee. This included risk informing the selection based in part on the Dresden Nuclear Power Station probabilistic risk assessment by generally selecting components that had a high Fussell Vesely Importance factor. Both safety-related and nonsafety-related components were considered in the selection process. Additional selection criteria included discussions with plant staff, reviewing procurement, maintenance, and design records, component location, Regulatory Guide (RG) 1.97, Criteria for Accident Monitoring Instrumentation for Nuclear Power Plants, instruments and walking down plant areas susceptible to high-energy line breaks. Based on these reviews, the inspectors focused the inspection on EQ Program elements and components repaired, modified, or replaced. Components from each unit were selected and included motor-operated valves, air operated valves, motors, electrical containment penetrations, breakers, and transmitters (pressure, flow, and level) located both inside and outside of containment. For each component selected, the inspectors evaluated the environmental qualifications of supporting sub-components including seals, lubricants, connectors, control and power cables, solenoids, transducers, limit switches, and terminal blocks.
This inspection constituted eight samples as defined in IP 71111.21N, Attachment 1, Section 02.01. The program Design Bases Inspection, in conjunction with the team portion of the Design Bases Inspection (IP 71111.21M), constitutes completion of the baseline triennial Component Design Bases Inspection (IP 71111.21).
.3 Component Design
a. Inspection Scope
The inspectors assessed the licensees implementation of the EQ Program as required by Title 10 of the Code of Federal Regulations, Part 50.49. The inspectors evaluated whether the licensee staff properly maintained the EQ of electrical equipment important to safety through plant life (repair, replacement, modification, and plant life extension),established and maintained required EQ documentation records, and implemented an effective Corrective Action Program (CAP) to identify and correct EQ-related deficiencies and evaluate EQ-related industry operating experience.
This inspection effort included a review of EQ Program-related procedures, component EQ files, EQ test records, equipment maintenance and operating history, maintenance and operating procedures, vendor documents, design documents, and calculations.
Additionally, the inspectors performed in-plant walkdowns of accessible components to verify installed equipment was the same as described in the EQ component documentation files, verify components were installed in their tested configuration, determine whether equipment surrounding the EQ component may fail in a manner that could prevent the EQ component from performing its safety function, and verify that components located in areas susceptible to a high energy line break were properly evaluated for operation in a harsh environment. Two components removed from the EQ program were reviewed to ensure an adequate basis existed to no longer require the components to meet EQ requirements. The inspectors reviewed procurement records and inspected a sample of replacement parts stored in the warehouse to verify EQ parts approved for installation in the plant were properly identified and controlled; and that storage time and environmental conditions did not adversely affect the components qualified life or service life. Documents reviewed for this inspection are listed in the
. The following eight EQ components (samples), including four components located within the drywell were reviewed:
Main Steam Isolation Valve (3-0203-2B); EQ sub-components: AC Solenoid (3-0203-2B-1) and DC Solenoid (3-0203-2B-2);
Isolation Condenser Reactor Outlet Isolation Motor-Operated Valves (2-1301-1);
EQ sub-components: actuator, limit switch, power cable, and motor; RG 1.97 Instrument; High-Pressure Coolant Injection Room Cooler Fan Motor (3-5747);
Low-Voltage Containment Penetration (2-1600-X-202-F);
High-Pressure Coolant Injection Turbine Auxiliary Oil Pump Breaker (3-83250-3AB1);
Main Steam Safety Relief Valve (2-203-4B) Leak Detector; EQ sub-components:
Acoustic Sensor (2-0261-63B) and Preamplifier (2-0261-64B); Nonsafety-Related; RG 1.97 Instrument; Main Steam Line Electromatic Relief Valve Actuator (2-0203-3E); and Recirculation Loop Sample Air-Operated Valves (3-0220-45); EQ sub-components:
Solenoid Valve and Limit Switch; RG 1.97 Instrument.
b. Findings
Main Steam Acoustic Safety/Relief Valve Monitoring Channel Calibration Not Performed
Introduction:
The inspectors identified a finding of very-low safety significance (Green)for the failure to perform a 24-month channel calibration of the RG 1.97 safety/relief valve acoustic monitoring system in accordance with the Technical Requirements Manual (TRM). Specifically, the licensee failed to perform a channel calibration, where the channel calibration shall encompass all devices in the channel required for channel operability and the channel functional test.
Description:
The inspectors reviewed EQ-01D, Environmental Qualification of NDT
[Non-Destructive Testing Company] Acoustic Safety/Relief Valve Monitoring System Sensor Model 838-1 & Preamplifier Model 400A. The inspectors determined from Tab E, Section 2, Maintenance and Surveillance Requirements to Maintain Qualification, the licensee was required to install new Raychem heat shrink tubing whenever the connector was disengaged for any reason. Based on this EQ Binder requirement, the inspectors reviewed documentation to verify during acoustic monitoring system activities that new Raychem heat shrink tubing was installed as directed by EQ-01D. The inspectors were also concerned based on the sensors EQ qualified life (i.e., >60 years) that existing Raychem heat shrink tubing was periodically inspected, if it was not replaced. The inspectors review also identified Tab D, Section 4.2 Justification for Including/Excluding of Maintenance and Surveillance Requirements, Paragraph 4.2.2, Requirement, stated, Perform the following calibration and evaluation activities every refueling outage [i.e., 24-months] or whenever the sensor is giving unusual data. These activities included the following:
Sensor sensitivity calibration Preamplifier checkout calibration System sensitivity calibration Alarm verification and Valve crosstalk evaluation The licensee stated that the above activities were considered non-EQ related and therefore, were not included in Tab E. However, EQ-01D stated the recommended calibration and evaluation activities shall be performed to satisfy the system performance and technical specification requirements or whenever the sensor sensitivity is in doubt.
The inspectors review also noted the main steam acoustic safety/relief valve monitoring instrumentation was a RG 1.97 variable. The instrumentation was designated in RG 1.97, Revision 2, Table 1, BWR [Boiling Water Reactor] Variables, as the primary system safety/relief valve positions instrumentation and classified as a Category 2, Type D variable. In addition, RG 1.97, Section 1.5h, stated for Category 1, 2, and 3 variables:
Periodic checking, testing, calibration, and calibration verification should be in accordance with the applicable portions of RG 1.118, Periodic Testing of Electric Power and Protection Systems, pertaining to testing of instrument channels. The Commonwealth Edison submittal, Dresden Station Units 2 and 3 Compliance with RG 1.97, dated August 1, 1985, stated the station complied with the requirements of RG 1.97, Revision 2, for the primary system safety/relief valve positions instrumentation variable.
The TRM, dated June 2013, Section 3.3.b, Post Accident Monitoring (PAM)
Instrumentation, required the acoustic safety/relief valve position indicators instrumentation shall be operable during plant Modes 1 and 2. The TRM Surveillance Requirement (TSR) 3.3.b.3, required a channel calibration be performed every 24-months for the acoustic safety/relief valve position indicators instrumentation. The TRM Section 1.1, Definitions, stated, in-part, that a channel calibration shall encompass all devices in the channel required for channel operability and the channel functional test. Licensee procedure DIS 0203-02, Safety and Safety/Relief Valve Acoustic Monitoring System Channel Calibrations and Functional Tests, satisfied the requirements of TSR 3.3.b.3.
To ensure EQ and RG 1.97 requirements were maintained, the inspectors reviewed DIS 0203-02, Work Order (WO) 01487194 01, IMD - D2 24M TS Safety & Acoustic Mon Chn Cal & Func Test, and WO 01692895 01, IMD - D2 24M TS Safety & Acoustic Mon Chn Cal & Func Test. Based on the inspectors review of the procedure and WO, the inspectors had the following concerns:
Did not perform a sensor sensitivity calibration and valve crosstalk evaluation, which was contrary to the requirements of EQ-01D, Tab D, Section 4.2, Paragraph 4.2.2, which stated the recommended calibration and evaluation activities shall be performed [every refueling outage (i.e., every 24-months)] to satisfy the system performance and technical specification requirements or whenever the sensor sensitivity is in doubt.
Did not meet the TRM, Section 1.1, definition of a complete channel calibration, where a channel calibration shall encompass all devices in the channel (e.g., the channel calibration did not include the sensor) required for channel operability and the channel functional test.
Did not meet the TSR 3.3.b.3, which required a channel calibration be performed every 24-months for the acoustic safety/relief valve position indicators instrumentation.
Provided and/or showed no reference in the procedure or WO data sheets that existing Raychem heat shrink tubing was periodically inspected, if it was not replaced.
Therefore, the inspectors concluded a complete channel calibration per the TRM was not performed every 24-months as required by the EQ Binder and questioned if Raychem heat shrink tubing was inspected and/or replaced during performance of the work orders. As a result, the licensee issued AR 02687869, AR 02692185, and AR 02692192.
Analysis:
The inspectors determined that the licenses failure to perform a 24-month channel calibration of the RG 1.97 safety/relief valve acoustic monitoring system was contrary to the TSR 3.3.b.3. Specifically, the licensee failed to perform a channel calibration, where the channel calibration shall encompass all devices in the channel required for channel operability and the channel functional test.
The performance deficiency was determined to be more than minor because the finding was associated with the Mitigating Systems cornerstone attribute of Procedure Quality and affected the cornerstones objective of ensuring the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the licensee failed to maintain the acoustic safety/relief valve position indicators instrumentation in accordance with the TSR 3.3.b.3.
In accordance with Inspection Manual Chapter 0609, Significance Determination Process, Attachment 0609.04, Initial Characterization of Findings, Table 2, the inspectors determined that the finding affected the Mitigating Systems cornerstone.
As a result, the inspectors determined the finding could be evaluated using Appendix A, The Significance Determination Process (SDP) for Findings At-Power, Exhibit 2, for the Mitigating Systems cornerstone. The performance deficiency affected the design or qualification of a mitigating SSC; however, the SSC maintained its functionality based on successful completion of channel functionality checks performed for TSR 3.3.b.1.
Therefore, the inspectors answered "yes" to the Mitigating Systems Screening Question A.1 in Exhibit 2 and screened the finding as having very-low safety significance (Green).
The inspectors did not identify a cross-cutting aspect associated with this finding because the finding was not representative of current performance.
This finding was entered into the licensees CAP as AR 02687869, AR 02692185, and AR 02692192. The licensees Design Engineering organization will review the EQ binder, TRM requirements, and surveillance procedure; and then recommend a resolution to this issue. (FIN 05000237/2016009-01; 05000249/2016009-01, Main Steam Acoustic Safety/Relief Valve Monitoring Channel Calibration Not Performed)
Enforcement:
Inspectors did not identify a violation of regulatory requirements associated with this finding.
.4 Operating Experience
a. Inspection Scope
The inspectors reviewed two EQ-related operating experience issues associated with the selected components to ensure that associated generic concerns had been adequately evaluated and addressed by the licensee. The operating experience issues listed below were reviewed as part of this inspection:NRC Information Notice 2014-04, Potential for Teflon Material Degradation in Containment Penetrations, Mechanical Seals; and OPXR 01162082-04, Limitorque Actuators Orientation and T-Drains.
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA2 Identification and Resolution of Problems
.1 Review of Items Entered Into the Corrective Action Program
a. Inspection Scope
The inspectors reviewed a sample of the selected component problems identified by the licensee and entered into the CAP. The inspectors reviewed these issues to assess the licensees threshold for identifying issues and the effectiveness of corrective actions related to design issues. In addition, corrective action documents written on issues identified during the inspection were reviewed to verify adequate problem identification and incorporation of the problem into the CAP. The specific corrective action documents sampled and reviewed by the inspectors are listed in the attachment to this report.
b. Findings
No findings were identified.
4OA6 Management Meeting(s)
.1 Exit Meeting Summary
On July 1, 2016, the inspectors presented the inspection results to Mr. J. Washko, and other members of the licensee staff. The licensee acknowledged the issues presented.
Several documents reviewed by the inspectors were considered proprietary information and were either returned to the licensee or handled in accordance with NRC policy on proprietary information.
ATTACHMENT:
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee
- J. Washko, Station Plant Manager
- M. Bcelman, Procurement Engineering Supervisor
- M. Budelier, Senior Engineering Manager
- D. Eaman, Senior Design Engineer
- M. Hosain, Site Equipment Qualification Engineer
- M. Hossain, Equipment Qualification Engineer
- B. Madderom, Engineering Manager
- M. Murskyj, Senior Engineering Manager
- S. Raja, Electrical Design Engineer
- A. Rehn, Sr. Licensing Engineer
- D. Walker, Regulatory Assurance - NRC Coordinator
- D. Wolverton, Engineering Manager
U.S. Nuclear Regulatory Commission
- M. Jeffers, Chief, Engineering Branch 2
- D. Hills, Chief, Engineering Branch 1
- R. Elliot, Resident Inspector
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Opened and Closed
- 05000237/2016009-01; FIN Main Steam Acoustic Safety/Relief Valve Monitoring
- 05000249/2016009-01 Channel Calibration Not Performed (Section 1R21.3.b)
Discussed
None LIST OF ACRONYMS USED ADAMS Agencywide Document Access Management System AR Action Request CAP Corrective Action Program CFR Code of Federal Regulations EQ Equipment Qualifications IP Inspection Procedure NRC U.S. Nuclear Regulatory Commission PARS Publicly Available Records System RG Regulatory Guide SSC System, Structure or Component TRM Technical Requirements Manual TSR TRM Surveillance Requirement WO Work Order Attachement