IR 05000482/2018011
| ML19015A018 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 01/14/2019 |
| From: | James Drake NRC/RGN-IV/DRS/EB-2 |
| To: | Heflin A Wolf Creek |
| Drake J | |
| References | |
| IR 2018011 | |
| Download: ML19015A018 (13) | |
Text
ary 14, 2019
SUBJECT:
WOLF CREEK GENERATING STATION, UNIT 1 - NRC INSPECTION OF TEMPORARY INSTRUCTION 2515/194, INSPECTION REPORT 05000482/2018011
Dear Mr. Heflin:
On December 13, 2018, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Wolf Creek Generating Station. On December 13, 2018, the inspector discussed the results of this inspection with Mr. J. McCoy, Site Vice President, and other members of your staff. The results of this inspection are documented in the enclosed report.
The NRC inspector did not identify any findings or violations of more than minor significance.
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/
James F. Drake, Acting Chief Engineering Branch 2 Division of Reactor Safety Docket Nos. 50-482 License Nos. NPF-42 Enclosure:
Inspection Report 05000482/2018011 w/ Attachment: TI 2515/194 Inspection Documentation Request
U.S. NUCLEAR REGULATORY COMMISSION
Inspection Report
Docket Number: 05000482 License Number NPF-42 Report Number: 05000482/2018011 Enterprise Identifier: I-2018-011-0051 Licensee: Wolf Creek Nuclear Operating Corporation Facility: Wolf Creek Generating Station Location: Burlington, Kansas Inspection Dates: December 3, 2018, to December 13, 2018 Inspector: B. Correll, Reactor Inspector Approved By: James F. Drake Acting Chief, Engineering Branch 2 Division of Reactor Safety Enclosure
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring licensees performance by conducting Temporary Instruction 2515/194, Inspection of the Licensees Implementation of Industry Initiative Associated with the Open Phase Condition Design Vulnerabilities in Electric Power Systems (NRC Bulletin 2012-01), at Wolf Creek, 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.
List of Findings and Violations No findings were identified.
INSPECTION SCOPE
This inspection was conducted using Temporary Instruction 2515/194 (ADAMS Accession No. ML17137A416), dated October 31, 2017. The inspector reviewed the licensees implementation of Nuclear Energy Institute voluntary industry initiative in compliance with Commission guidance. The inspector discussed the licensees open phase condition system design and ongoing implementation plans with plant staff. The inspector reviewed licensee and vendor documentation, and performed system walkdowns to verify that the installed equipment was supported by the design documentation. The inspector verified that the licensee had completed the installation and testing of equipment (with the exception of the tripping functions),installed and tested alarming circuits both local and in the control room, and analyzed potential impacts associated with the design implementation on the current licensing basis.
OTHER ACTIVITIES
- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL Temporary Instruction 2515/194 - Inspection of the Licensees Implementation of Industry Initiative Associated With the Open Phase Condition Design Vulnerabilities in Electric Power Systems (NRC Bulletin 2012-01)
The objective of Temporary Instruction 2515/194 is to verify that licensees have appropriately implemented the Nuclear Energy Institute voluntary industry initiative (ADAMS Accession No. ML15075A454), dated March 16, 2015, including updating their licensing basis to reflect the need to protect against open phase conditions.
Temporary Instruction 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
Wolf Creek Generating Station selected the open phase detection system designed and manufactured by Power System Sentinel Technologies, LLC. At the end of this inspection the system remained in the monitoring mode of operation to facilitate continued data gathering of grid perturbations for evaluation of alarm and trip setpoints. The equipment was installed on the start-up transformer XMR01 and transformer 7. The licensee is scheduled to transition the open phase detection system to full implementation (tripping functions enabled) by May 18, 2020, in accordance with Nuclear Energy Institute Open Phase Condition Initiative, dated September 2018, Revision 2. The licensee was preparing associated documentation for this transition, however only proposed changes were available for review at the time of inspection.
INSPECTION RESULTS
- OBSERVATIONS/ASSESSMENT Based on discussions with the licensee staff, review of available design, testing, grid data trending results documentation, and walkdowns of installed equipment, the inspector had reasonable assurance the licensee appropriately implemented the voluntary industry initiative.
The inspector determined that:
Detection, Alarms, and General Criteria TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
- (1) Open phase conditions will be detected and alarmed in the control room on the common annunciator panel, with an exception for the alternate alignment path for one offsite source.
- (2) Detection circuits will be sensitive enough to identify an open phase condition for all credited loading conditions for installed equipment.
- (3) No Class-1E circuits were being replaced with non-Class 1E circuits in the design.
Protective Actions Criteria TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
- (1) Five transformers were susceptible to an open phase condition and the licensee had installed detection and mitigating equipment for two of the five. The remaining three transformers will be discussed as an exception.
- (2) With an open phase condition present and with or without an accident condition signal, the open phase design would not adversely affect the function of important-to-safety systems, structures, or components. The licensees open phase condition design solution added two Power System Sentinel Technologies, LLC systems on the start-up transformer XMR01 and two systems on transformer 7. The tripping function, when enabled, will provide an additional input to the associated transformer lockout relays.
The credited plant response is unaffected and will be the same regardless of the conditions that generated the lockout of the transformer.
No findings were identified.
The inspector identified the following exceptions to the Temporary Instruction criteria resulting from the incomplete design modifications:
Detection, Alarms, and General Criteria Exceptions TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
- (1) The licensees design was operating in the monitoring mode with established setpoints to gather data to ensure the open phase condition design and protective schemes would minimize misoperation, or spurious actions in the range of voltage unbalance normally expected in the transmission system. Because actual demonstration of this criterion required the system to be in operation with final trip setpoints established, the inspector was not able to fully verify this criterion. After discussions with licensee staff, design document and test result reviews, the inspector had reasonable assurance that the actuation circuit design would not result in lower overall plant reliability.
- (2) The Updated Safety Analysis Report and Technical Specification Bases had not been updated to include information related to open phase conditions at the conclusion of the onsite inspection. The licensee provided the inspector with proposed changes to the licensing basis that discussed the system requirements related to the effects of, and protection for, any open phase condition design vulnerability. The licensee continued to modify and update the proposed changes during the onsite portion of the inspection. The inspector verified the proposed change process was being tracked under document change package CP 14570 for the completion of the Updated Safety Analysis Report updates. The inspector did not identify any issues of concern.
- (3) The inspector identified an alternate alignment path for one of the credited offsite sources (start-up transformer XNB01) that was not monitored for open phase conditions associated with three transformers (transformers 4, 5, and 6). This alignment path is infrequently utilized and contains a relatively short length of conductors and equipment that would be susceptible to open phase conditions. This alternate path was infrequently used in the past and has been aligned for a cumulative 47.5 days over the previous 25 year period. Also, only about 150 yards of switchyard bus bars, circuit breakers, and transformer connections would be susceptible to open phase conditions and were not monitored for open phase conditions. These factors aided in creating a very low risk condition for this alternate path alignment. The licensee proposed corrective actions to no longer consider this alternate path alignment as a credited source for the offsite circuit for start-up transformer XNB01, and was being evaluated by Condition Report 00128627.
The corrective action would require the licensee to declare start-up transformer XNB01 offsite source inoperable while aligned to this alternate source, and enter the Technical Specifications limiting condition for operation action statement when aligned to this path.
The licensee has until full implementation of the Nuclear Energy Institute voluntary industry initiative to implement these corrective actions.
Protective Actions Criteria Exceptions TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
- (1) The licensees open phase condition design solution uses Power System Sentinel Technologies, LLC to detect, alarm, and provide an input to the associated transformer lockout relays. Upon transformer lockout, the existing undervoltage relays would operate as designed to initiate starting of the emergency diesel generator to restore power to the bus.
The tripping function input to the transformer lockout relays remained disabled during the onsite portion of the inspection and was not able to be demonstrated to perform the designed function. This action was being tracked in the design change package CP 14570. Through review of design documents and discussions with licensee staff, the inspector had reasonable assurance that with an open phase condition present and with and without an accident condition signal, the open phase design would isolate the affected bus and cause an automatic restoration of power from the emergency diesel generators. Due to the configuration of Wolf Creek Generating Stations electrical distribution system, a loss of phase on one transformer would only affect one train of equipment, and loads required to mitigate postulated accidents would be available on the non-affected train, ensuring that safety functions are preserved as required by the current licensing bases. The inspector did not identify any issues of significance.
- (2) At the time of this inspection, the licensee had not finalized documentation for periodic tests, calibrations, setpoint verifications, or inspection procedures associated with the Power System Sentinel Technologies, LLC equipment. This action was being tracked in the design change package CP 14570.
The licensee has not determined the preventive maintenance process for the installed equipment and has Work Order 13-378853-073 to perform this evaluation. Existing plant equipment will continue to be maintained according to the licensees current preventative maintenance program. The inspector did not identify any issues of concern.
EXIT MEETINGS AND DEBRIEFS
On December 13, 2018, the inspector conducted an exit meeting to present the Temporary Instruction 2515/194 inspection results to Mr. J. McCoy, Site Vice President, and other members of the licensee staff. The inspector verified no proprietary information was retained.
DOCUMENTS REVIEWED
Temporary Instruction 2515/194 - Inspection of the Licensees Implementation of Industry
Initiative Associated with the Open Phase Condition Design Vulnerabilities in Electric Power
Systems (NRC Bulletin 2012-01)
Condition Report
00128627*
Drawings
Number Title Revision
E-003.3A-00001 Schematic Diagram and Wiring List SUT Open 01
Phase Detection System Channel 1
E-003.3A-00002 Schematic Diagram and Wiring List SUT Open 01
Phase Detection System Channel 2
KD-7496, Sh. 1 One Line Diagram 67
WIP-E-11026-004-A-1 Relay Setting Tabulation 01
WIP-E-11MR01-007-B-1 Startup Transformer Single Line Metering and 00
Relaying Diagram
WIP-E-12MR01-000-A-1 Startup Transformer Protection Logic Diagram 00
WIP-E-13MR10-009-B-1 Schematic Diagram Startup Transformer Protection 00
Engineering Reports
Number Title Revision
E-11023 Relay Setting Tabulation and Coordination Curves 10
System NB
XX-E-039 Open Phase Analysis 0
Miscellaneous
Documents
Number Title Date
15-00846 Interconnection Guidelines September 17,
2015
ET 18-0032 Docket No. 50-482: Wolf Creek Nuclear Operating December 7,
Corporation Change of Date for Full Implementation 2018
of Open Phase Detection System
Procedures Revision
Number Title or Date
ALR 00-012A 345 KV Trouble 9
Procedures Revision
Number Title or Date
ALR 00-014D S/U XFMR Trouble 13
ALR 843 #7 Transformer Open Phase Detection Trouble 0
CKL ZL-009 Site Readings Sheets 109
OFN AG-025 Unit Limitations 55
SYS NB-200 Transferring XNB01 Supply Between SL7 and 20
- 7 Transformer
SYS NB-201 Transferring NB01 Power Sources 61
TSO 0102-00 Waverly Wind Farm Capacitor Usage September 17,
2015
Vendor
Document
Number Title Revision
2015WCN5144 Open Phase Protection (OPP) FAT Report for Wolf 4.0.0
Creek Generating Station Dual Cabinet System with
Serial Numbers 7E0694367 and 7E0698202
Work Order
13-378853-047
TI 2515/194 Inspection Documentation Request
Please provide the following documentation (Items 1 - 8) to the lead inspector prior to the onsite
inspection date, preferably no later than November 5, 2018. Whenever practical, please provide
copies electronically (IMS/CERTREC is preferred). Please provide an index of the requested
documents which includes a brief description of the document and the numerical heading
associated with the request (i.e., where it can be found in the list of documents requested).
Brian Correll, Lead Inspector
RIV/DRS/EB2
1600 E. Lamar Blvd.
Arlington, TX 76011
817-200-1565
brian.correll@nrc.gov
1. Copies of any calculations, analyses, and/or test reports performed to support the
implementation of your open phase condition (OPC) solution. If, in your implementation,
OPCs are not detected and alarmed in the control room please include documentation that:
a. Demonstrates the OPC will not prevent functioning of important-to-safety SSCs; AND
b. Detection of an OPC will occur within a short period of time (e.g., 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />).
2. Copies of any modification packages, including 10 CFR 50.59 evaluations if performed,
used for or planned for the implementation of your OPC solution.
3. Copies of periodic maintenance, surveillance, setpoint calibration, and/or test procedures
implemented or planned, for your OPC solution.
4. Copies of your licensing basis changes to Updated Final Safety Analysis Report (UFSAR)
and/or Technical Specifications (TS), as applicable, which discuss the design features and
analyses related to the effects of, and protection for, any open phase condition design
vulnerability. If these documents have not been updated, provide documentation of your
plans to do so.
5. Copies of any procurement specifications and acceptance testing documents related to the
installation of your OPC solution.
6. Copies of any site training the team will need to accomplish to gain access to areas with, or
planned, major electrical equipment used in your OPC solution (i.e. switchyard).
7. Provide documentation showing that with an OPC occurrence and no accident condition
signal present, either:
a. An OPC does not adversely affect the function of important-to-safety SSCs, OR
b. TS LCOs are maintained or the TS actions are met without entry into TS LCO 3.0.3
AND
i. Important-to-safety equipment is not damaged by the OPC, AND
ii. Shutdown safety is not compromised
8. With OPC occurrence and an accident condition signal present:
a. Provide documentation showing that automatic detection and actuation will transfer
loads required to mitigate postulated accidents to an alternate source and ensure
that safety functions are preserved, as required by the current licensing bases, OR
b. Provide documentation showing that all design basis accident acceptance criteria are
met with the OPC, given other plant design features. Accident assumptions must
include licensing provisions associated with single failures. Typically, licensing bases
will not permit consideration of the OPC as the single failure since this failure is a
non-safety system.
Please provide the following documentation to the team when they arrive onsite. Whenever
practical, please provide copies electronically, except for drawings. Drawings should be
provided as paper copies of sufficient size (ANSI C or D) such that all details are legible.
9. A brief presentation describing your electric power system design and typical electrical
transmission and distribution system alignments; OPC design schemes installed to detect,
alarm and actuate; bus transfer schemes; and maintenance and surveillance requirements.
This presentation should be a general overview of your system. Please schedule the
overview shortly after the entrance meeting.
10. Plant layout and equipment drawings for areas that identify: (a) the physical plant locations
of major electrical equipment used in your open phase condition solution; (b) the locations of
detection and indication equipment used in the open phase condition sensing circuits.
11. If OPC actuation circuits are required, provide documentation that demonstrates continued
coordination with the other protective devices in both the offsite electrical system (within
Wolf Creek Generating Stations area of responsibility) and the onsite electrical systems.
2. Access to locations in which open phase condition equipment is installed or planned (i.e.
switchyard, etc.)
13. Copies of documentation or testing that demonstrates your OPC solution minimizes spurious
actuation or misoperation in the range of voltage imbalance normally expected in the
transmission system that could cause undesired separation from an operable off-site power
source.
This document does not contain new or amended information collection requirements
subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). Existing
information collection requirements were approved by the Office of Management and
Budget, Control Number 31500011. The NRC may not conduct or sponsor, and a person
is not required to respond to, a request for information or an information collection
requirement unless the requesting document displays a currently valid Office of
Management and Budget control number.
This document 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.
SUNSI Review: ADAMS: Non-Publicly Available Non-Sensitive Keyword: NRC-002
By: BKC Yes No Publicly Available Sensitive
OFFICE RI:EB2 AC:EB2 C:PBB AC:EB2
NAME BCorrell JDrake NTaylor JDrake
SIGNATURE /RA/ /RA/ /RA/ /RA/
DATE 1/8/2019 1/8/2019 1/11/2019 1/14/2019