IR 05000445/2018012

Comanche Peak Nuclear Power Plant - NRC Inspection of Temporary Instruction 2515/194, Inspection Report 05000445/2018012 and 05000446/2018012

ML18285A725
Person / Time
Site:	Comanche Peak
Issue date:	10/12/2018
From:	Greg Werner NRC/RGN-IV/DRS/EB-2
To:	Peters K Vistra Operations Company
Werner G
References
IR 2018012
Download: ML18285A725 (13)

Text

ber 12, 2018

SUBJECT:

COMANCHE PEAK NUCLEAR POWER PLANT - NRC INSPECTION OF TEMPORARY INSTRUCTION 2515/194, INSPECTION REPORT 05000445/2018012 AND 05000446/2018012

Dear Mr. Peters,

On September 13, 2018, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Comanche Peak Nuclear Power Plant, Units 1 and 2. On September 13, 2018, the NRC inspector discussed the results of this inspection with Mr. Tom McCool, 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 finding or violation 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/

Gregory E. Werner, Chief Engineering Branch 2 Division of Reactor Safety Docket Nos. 50-445 and 50-446 License Nos. NPF-87 and NPF-89 Enclosure:

Enclosure: Inspection Report 5000445/2018012 and 05000446/2018012 w/ Attachment: TI 2515/194 Inspection Documentation Request

U.S. NUCLEAR REGULATORY COMMISSION

Inspection Report

Docket Numbers: 05000445 and 05000446 License Numbers: NPF-87, NPF-89 Report Numbers: 05000445/2018012 and 05000446/2018012 Enterprise Identifier: I-2018-012-0018 Licensee: Vistra Operations Company, LLC Facility: Comanche Peak Nuclear Power Plant, Units 1 and 2 Location: Glen Rose, Texas Inspection Dates: September 10, 2018, to September 13, 2018 Inspector: S. Graves, Senior Reactor Inspector Approved By: Gregory E. Werner Chief, Engineering Branch 2 Division of Reactor Safety Enclosure

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a 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 Comanche Peak Nuclear Power Plant, Units 1 and 2, 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.

Additional Tracking Items None.

INSPECTION SCOPE

This inspection was conducted using Temporary Instruction 2515/194 (ADAMS Accession No. ML17137A416), issue date 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 and planned equipment was supported by the design documentation. The licensee had not completed the installation and testing of all related equipment by the end of the inspection.

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)

Vistra Operations Company, LLC selected the open phase detection system designed and manufactured by Power System Sentinel Technologies, LLC, as the design vendor for Comanche Peak Nuclear Power Plant. At the end of this inspection the licensee had installed one complete system on startup transformer XST1, but had not completed final testing. Startup transformer XST2A installation was in progress with testing scheduled. System installation on the other two startup transformers, XST1A and XST2, was in progress. The licensee is scheduled to transition each Power System Sentinel Technologies system to a monitoring mode of operation (tripping functions disabled) as individual installations are completed, followed by transition to full operation (tripping functions enabled) in December 2019. The licensee was preparing design modifications and associated documentation for this transition, however they were not complete at the time of inspection. The licensee documented activities associated with this design change and installation in action items under condition report CR-2016-005840.

INSPECTION RESULTS

- OBSERVATIONS/ASSESSMENT Based on discussions with licensee staff, review of available design and testing documentation, and walkdowns of installed and prepared equipment, the inspector had reasonable assurance the licensee is appropriately implementing, with noted exceptions discussed below, the voluntary industry initiative.

The inspector determined by design document review, walkdowns, staff discussions, and observation 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 for each unit on the common annunciator panel.

(2) Detection circuits will be sensitive enough to identify an open phase condition for all credited loading conditions.

(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) The transformers were susceptible to an open phase condition and the licensee was implementing design changes to mitigate the effects.

(2) With an open phase condition present and no accident condition signal, the Power System Sentinel Technologies system would not adversely affect the function of important-to-safety systems, structures, or components. The licensees open phase condition design solution added a set of additional tripping inputs in parallel with existing transformer isolation controls. This addition added a new tripping condition (open phase) to the previously analyzed electrical faults which result in isolation of one startup transformer. The credited plant response was unaffected and would be the same regardless of the conditions that generated the isolation 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 installation was in progress on the four startup transformers.

Vendor recommended trip and alarm setpoints were established, and one set of detection and alarm circuitry had been installed, waiting for final testing with others in progress or planned. After installation, the licensee planned to gather data in a monitoring mode of operation 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 requires 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, walkdown of control room panels where the open phase condition alarm had been connected and design document and test results reviewed, the inspector had reasonable assurance that the actuation circuit design would not result in lower overall plant operation reliability. The licensee currently has the ability to read phase-to-phase voltages and line voltages on the transformer lines. The inspector did not identify any issues of concern.

(2) The Final Safety Analysis Report had not been updated to include information related to open phase conditions at the conclusion of the onsite inspection. The licensee provided a copy of action item TR-2016-005840-44, written to track review of open phase protection system impacts to the Final Safety Analysis Report. The inspector held discussions with senior licensee staff related to the guidelines for licensing basis document updates and the voluntary industry initiative items. The licensee expected to update their Final Safety Analysis Report after completion. The inspector did not identify any issues of concern.

Protective Actions Criteria Exceptions TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)

(1) The open phase condition design solution will use the existing isolation and power scheme for safety-related accident loads; only a new tripping condition (open phase)is being added to the electrical faults which result in isolation of one preferred source of power. A loss of voltage, including a loss of voltage caused by isolation of the preferred source due to an open phase condition, on the affected safety-related bus results in the affected trains electrical loads being automatically transferred to the onsite emergency power source. While no changes to this configuration were planned due to the inclusion of the Power System Sentinel Technologies system, actual demonstration of this criterion requires the system to be in full operation

(2) At the time of this inspection, the licensee had not finalized documentation for periodic tests, calibrations, setpoint verifications, or inspection procedures for open phase protection system components. The inspector held discussions with licensee staff and identified that the vendor guidance, including periodic tests, setpoint verification, and equipment maintenance and inspection would be integrated into plant procedures and processes. The licensee entered this issue into their corrective action program as action item TR-2016-005840-14, to develop preventive maintenance and testing strategies for the open phase protection system. Licensee staff also explained that existing equipment in the transformer control circuit was part of the licensees maintenance rule program (10 CFR 50.65), with an expectation that the open phase equipment would also be reviewed for inclusion in the program.

The license entered this into their corrective action program as action item TR-2016-005840-20. The licensee also captured inspector observations and questions related to additional inspection criteria for the transformers neutral cable, neutral bushing, and ground connection integrity. These issues were entered into the corrective action program as action items TR-2016-005840-45, -46, -47, and -48.

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 September 13, 2018, the inspector presented the Temporary Instruction 2515/194 inspection results to Mr. T. McCool, Site Vice President, and other members of the licensee staff. The inspector verified no proprietary information was retained or documented in this report.

DOCUMENTS REVIEWED

Drawings Number Title Revision

SK-001-16-000005-02-01 138 KV Startup Transf XST1 Lockout 01

Relay 86-2/ST1 Schematic Diagram

E1-0002 Transformers XST1, XST1A, XST2 and XST2A CP-2

Cable Block Diagram

E1-0002 Main One Line Meter and Relay Diagram CP-27

E1-0002 Main One Line Meter and Relay Diagram CP-16

8.2.4 Electrical Network Interconnections

3918D853SB Elementary Diagram TR, 138KV Startup 4

Transformer

OPP-ELE-B101, Electrical Drawings

Sheets 1-17

OPP-ELE-B201, Electrical Drawings

Sheets 1-17

Design Documents Number Title Revision

FDA-2016-000005-02-01 Final Design Authorization - Install Open Phase 1

Detection System for XST1

FDA-2016-000005-03-02 Conformed Specification 2

FDA-2016-000005-04-00 Final Design Authorization - Install Open Phase 0

Detection System for XST2

FDA-2016-000005-05-00 Final Design Authorization - Install Open Phase 0

Detection System for XST1A

FDA-2016-000005-06-00 Final Design Authorization - Install Open Phase 0

Detection System for XST2A

VDRT-5575487 Factory Acceptance Test Reports for XST1 Open

Phase Protection System

VDRT-5599260 Factory Acceptance Test Reports for Open

Phase Protection System

DBD-EE-038, Section 6.2.2 Offsite Power System - Accessories and Alarms 24 and

Updates Pending

DBD-EE-051, Section 5.1.1 Protection Philosophy - Unit Connected 45 and

Equipment and Startup Transformers Pending

Miscellaneous Document

Number Title Revision

CPESE1138 Conformed System (Device) Requirements 2

Specification

Procedures Number Title Revision

ALM-0140 Alarm Procedure X-ALB-14 11

Vendor Documents

Number Title Revision

IEGR-DD-1701 Open Phase Protection (OPP) System 0.0.5

Non-Class 1E OPP Protection Settings,

Comanche Peak NPP XST1 & XST1A

IEGR-DD-1741 Open Phase Protection (OPP) System 0.0.3

Non-Class 1E OPP Protection Settings,

Comanche Peak NPP XST2 & XST2A

ITST-TP-1877 Open Phase Protection (OPP) System 0.0.0

Site Acceptance Test (SAT) Plan for One

Channel of a Dual Channel System for

Comanche Peak

ITST-TP-1878 Open Phase Protection (OPP) System 0.0.0

Site Acceptance Test (SAT) Plan for Dual

Channel System for Plant Comanche Peak

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 August 27, 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).

Sam Graves, Inspector

RIV/DRS/EB2

1600 E. Lamar Blvd.

Arlington, TX 76011

817-200-1102

Samuel.graves@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 inspector 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 inspector 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

Comanche Peaks 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.

ML18285A725

SUNSI Review: ADAMS: Non-Publicly Available Non-Sensitive Keyword: NRC-002

By: STG Yes No Publicly Available Sensitive

OFFICE SRI:EB2 C:EB2 C: PBA C:EB2

NAME SGraves GWerner MHaire GWerner

SIGNATURE /RA/ /RA/ /RA/ /RA/

DATE 10/05/2018 10/10/2018 10/11/2018 10/12/2018