|
---|
Category:Inspection Report
MONTHYEARIR 05000275/20230042024-02-0909 February 2024 Integrated Inspection Report 05000275/2023004 and 05000323/2023004 IR 05000275/20230112024-01-12012 January 2024 NRC License Renewal Phase 1 Inspection Report 05000275/2023011 IR 05000275/20230032023-11-13013 November 2023 Integrated Inspection Report 05000275/2023003 and 05000323/2023003 IR 05000275/20240152023-10-10010 October 2023 Information Request for the Cybersecurity Baseline Inspection, Notification to Perform Inspection (050002752024015 and 050003232024015) IR 05000275/20243012023-08-24024 August 2023 Notification of NRC Initial Operator Licensing Examination 05000275/2024301; 05000323/2024301 IR 05000275/20230052023-08-22022 August 2023 Updated Inspection Plan for Diablo Canyon Power Plant, Units 1 and 2 (Report 05000275/2023005 and 05000323/2023005) - Mid Cycle Letter IR 05000275/20230022023-08-14014 August 2023 Quarterly Integrated Inspection Report 05000275/2023002 and 05000323/2023002- August 7, 2023 IR 05000275/20213012023-08-0909 August 2023 Errata for Diablo Canyon Power Plant, Units 1 and 2 - NRC Examination Report 050002752021301 and 050003232021301 IR 05000275/20234022023-08-0303 August 2023 NRC Security Inspection Report 05000275/2023402, and 05000323/2023402 IR 05000275/20233012023-07-25025 July 2023 NRC Initial Operator Licensing Examination Approval 05000275/2023301, 05000323/2023301 IR 05000275/20230102023-05-11011 May 2023 NRC Inspection Report 05000275 2023010 and 05000323 2023010 IR 05000275/20230012023-05-0909 May 2023 Integrated Inspection Report 05000275/2023001 and 05000323/2023001 IR 05000275/20234032023-03-10010 March 2023 NRC Security Baseline Inspection Report 05000275/2023403, 05000323/2023403 (Full Report) IR 05000275/20220062023-03-0101 March 2023 Annual Assessment Letter for Diablo Canyon Power Plant, Units 1 and 2 (Report 05000275/2022006 and 05000323/2022006) IR 05000275/20220042023-02-0202 February 2023 Integrated Inspection Report 05000275/2022004 and 05000323/2022004 IR 05000275/20220102023-01-27027 January 2023 Biennial Problem Identification and Resolution Inspection Report 05000275/2022010 and 05000323/2022010 IR 05000275/20224022022-10-26026 October 2022 Security Baseline Inspection Report 05000275/2022402 and 05000323/ 2022402 IR 05000275/20220032022-10-24024 October 2022 Integrated Inspection Report 05000275/2022003 and 05000323/2022003 and Exercise of Enforcement Discretion IR 05000275/20220052022-08-23023 August 2022 Updated Inspection Plan for Diablo Canyon Power Plant, Units 1 and 2 (Report 05000275/2022005 and 05000323/2022005) IR 05000275/20220022022-08-10010 August 2022 Integrated Inspection Report 05000275/2022002 and 05000323/2022002 IR 05000275/20220112022-08-0909 August 2022 Design Basis Assurance Inspection (Teams) Inspection Report 05000275/2022011 and 05000323/2022011 IR 05000275/20224012022-08-0303 August 2022 NRC Security Inspection Report 05000275/2022401, 05000323/2022401 ML22143A8812022-05-26026 May 2022 Revised Integrated Inspection Report 05000275/2022001 and 05000323/2022001 ML22118A9362022-05-0505 May 2022 Integrated Inspection Report 05000275/2022001 and 05000323/2022001 IR 05000275/20220012022-05-0505 May 2022 Integrated Inspection Report 05000275/2022001 and 05000323/2022001 IR 05000323/20214202022-03-31031 March 2022 Security Inspection Report 05000275 and 05000323/2021420 IR 05000275/20210062022-03-0202 March 2022 Annual Assessment Letter for Diablo Canyon Power Plant, Units 1 and 2 (Report 05000275/2021006 and 05000323/2021006) IR 05000275/20210042022-02-0303 February 2022 Integrated Inspection Report 05000275/2021004 and 05000323/2021004 IR 05000275/20214042022-01-13013 January 2022 Public - Security Baseline Inspection Report 05000275/2021404 and 05000323/2021404 IR 05000275/20210032021-11-0303 November 2021 Integrated Inspection Report 05000275/2021003 and 05000323/2021003 IR 05000275/20210112021-09-10010 September 2021 Design Basis Assurance Inspection (Programs) Report 05000275/2021011 and 05000323/2021011 IR 05000275/20214052021-08-0505 August 2021 Security Baseline Inspection Report 05000275/2021405 and 05000323/2021405 IR 07200026/20214012021-08-0303 August 2021 Diablo Canon Nuclear Power Plant, Security Baseline Inspection Report 07200026/2021401 IR 05000275/20210022021-08-0202 August 2021 Integrated Inspection Report 05000275/2021002 and 05000323/2021002 IR 05000275/20210122021-07-28028 July 2021 Temporary Instruction 2515/194 Report 05000275/2021012 and 05000323/2021012 IR 05000275/20214012021-07-0101 July 2021 Security Baseline Inspection Report 05000275/2021401 and 05000323/2021401 IR 05000275/20210012021-05-0707 May 2021 DC IR 2021-001-drk, Diablo Canyon Power Plant Units 1 & 2 - Integrated Inspection Report 05000275/2021001, 05000323/2021001, & Independent Spent Fuel Storage Installation Inspection Report 07200026/2021001 DCL-21-036, One Hundred Eighty Day Steam Generator Report for Diablo Canyon Power Plant Unit 1 Twenty-Second Refueling Outage2021-04-22022 April 2021 One Hundred Eighty Day Steam Generator Report for Diablo Canyon Power Plant Unit 1 Twenty-Second Refueling Outage ML21102A0702021-04-12012 April 2021 Notification of NRC Design Bases Assurance Inspection (Programs) (05000275/2021011 and 05000323/2021011) and Initial Request for Information IR 05000275/20214032021-03-31031 March 2021 Cyber Security Inspection Report 05000275/2021403 and 05000323/2021403 IR 05000275/20210102021-03-11011 March 2021 Triennial Fire Protection Inspection Report 05000275/2021010 and 05000323/2021010 IR 05000275/20200062021-03-0303 March 2021 DC 2020 Annual Assessment Letter for Diablo Canyon Power Plant, Units 1 & 2 (Report 05000275/2020006 & 05000323/2020006) IR 05000275/20200042021-01-26026 January 2021 Integrated Inspection Report 05000275/2020004 and 05000323/2020004 IR 05000275/20204112020-12-22022 December 2020 Security Baseline Inspection Report 05000275/2020411 and 05000323/2020411 IR 05000275/20204102020-12-15015 December 2020 NRC Security Inspection Report 05000275/2020410 and 05000323/2020410 IR 05000275/20200102020-10-30030 October 2020 Biennial Problem Identification and Resolution Inspection Report 05000275/2020010 and 05000323/2020010 IR 05000275/20200032020-10-29029 October 2020 Integrated Inspection Report 05000275/2020003 and 05000323/2020003 IR 05000275/20200052020-09-0101 September 2020 Updated Inspection Plan for Diablo Canyon Power Plant, Units 1 and 2 (Report 05000275/2020005 and 05000323/2020005) IR 05000275/20200022020-07-22022 July 2020 Integrated Inspection Report 05000275/2020002 and 05000323/2020002 IR 05000275/20200012020-04-16016 April 2020 Integrated Inspection Report 05000275/2020001 and 05000323/2020001 2024-02-09
[Table view] Category:Letter
MONTHYEARIR 05000275/20230042024-02-0909 February 2024 Integrated Inspection Report 05000275/2023004 and 05000323/2023004 ML24002B1802024-01-29029 January 2024 LRA Audit Plan DCL-24-010, Nuclear Material Transaction Report for New Fuel2024-01-29029 January 2024 Nuclear Material Transaction Report for New Fuel ML24018A0152024-01-29029 January 2024 License Renewal Application Review Schedule Letter ML24017A2492024-01-24024 January 2024 Letter to Neil Peyron, Chairman, Tule River Tribe, Re. Diablo Canyon ML24024A1752024-01-24024 January 2024 Letter to Tribal Council San Luis Obispo County Chumash Indians on Section 106 Consultation and Scoping Process for the Environmental Review of Diablo Canyon Nuclear Plant, Unit 1 and 2 License Renewal Application ML24003A8902024-01-24024 January 2024 Letter to P. Gerfen - Diablo Canyon Notice of Intent to Conduct Scoping and Prepare an Environmental Impact Statement ML24012A1582024-01-24024 January 2024 Letter to Hon. Violet Sage Walker, Chairwoman Northern Chumash Tribal Council on Section 106 Consultation and Scoping Process for the Environmental Review of Diablo Canyon Nuclear Plant, Unit 1 and 2 License Renewal Application ML24012A0062024-01-24024 January 2024 Achp Scoping Letter for Diablo Canyon License Renewal ML24012A0552024-01-24024 January 2024 Letter to J. Polanco, Shpo, on Request to Initiate Section 106 Consultation and Scooping Process for the Environmental Review of Diablo Canyon Nuclear Plant, Unit 1 and 2 License Renewal Application ML24024A1562024-01-24024 January 2024 Letter to Hon. Gabe Frausto, Coastal Band of Chumash Indians on Section 106 Consultation and Scoping Process for the Environmental Review of Diablo Canyon Nuclear Plant, Unit 1 and 2 License Renewal Application ML24024A1652024-01-24024 January 2024 Letter to Hon. Mona Olivas Tucker, Yak Tityu Tityu Yak Tilhini Northern Chumas Indians on Section 106 Consultation and Scoping Process for the Environmental Review of Diablo Canyon Nuclear Plant, Unit 1 and 2 License Renewal Application ML24024A1612024-01-24024 January 2024 Letter Hon. Gary Pierce, Salian Tribe of Monterey and San Luis Obispo Counties on Section 106 Consultation and Scoping Process for the Environmental Review of Diablo Canyon Nuclear Plant, Unit 1 and 2 License Renewal Application ML24012A0362024-01-24024 January 2024 Request to Initiate Section 106 Consultation and Scoping Process for the Environmental Review License Renewal Application DCL-24-009, Nuclear Material Transaction Report for New Fuel2024-01-17017 January 2024 Nuclear Material Transaction Report for New Fuel DCL-24-008, Schedule Considerations for Review of the DCPP License Renewal Application2024-01-17017 January 2024 Schedule Considerations for Review of the DCPP License Renewal Application DCL-24-004, Supplement to License Amendment Request 23-01 Revision to Technical Specifications to Adopt Risk-Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b2024-01-15015 January 2024 Supplement to License Amendment Request 23-01 Revision to Technical Specifications to Adopt Risk-Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b IR 05000275/20230112024-01-12012 January 2024 NRC License Renewal Phase 1 Inspection Report 05000275/2023011 DCL-23-129, Nuclear Material Transaction Report for New Fuel2023-12-27027 December 2023 Nuclear Material Transaction Report for New Fuel ML23326A0122023-12-21021 December 2023 12-21-23 Letter to the Honorable Byron Donalds from Chair Hanson Responds to Letter Regarding 2.206 Petition to Close Diablo Canyon Nuclear Power Plant, Unit 1 ML23341A0042023-12-19019 December 2023 LRA Acceptance Letter ML23352A2342023-12-18018 December 2023 Notification of Age-Related Degradation Inspection (05000275/2024014 and 05000323/2024014) and Request for Information DCL-23-122, Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation2023-12-14014 December 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation DCL-23-128, Emergency Plan Update2023-12-13013 December 2023 Emergency Plan Update ML23355A0952023-12-0808 December 2023 License Renewal Application Online Reference Portal DCL-23-125, Core Operating Limits Report for Unit 1 Cycle 252023-12-0606 December 2023 Core Operating Limits Report for Unit 1 Cycle 25 ML23291A2702023-11-28028 November 2023 Letter to Nakia Zavalla, Shpo, the Santa Ynez Band of Chumash Indians; Re., Diablo Canyon ISFSI Initiating Section 106 Consultation ML23320A2442023-11-28028 November 2023 Letter to Kerri Vera, Director of Department of Environmental Protection, Tule River Tribe; Re., Diablo Canyon ISFSI Initiating Section 106 Consultation ML23325A1382023-11-27027 November 2023 ISFSI Tribal Letter to San Luis Obispo County Chumash Indians ML23325A1322023-11-27027 November 2023 ISFSI Tribal Letter to Salian Tribe of Montgomery, San Luis Obispo ML23325A1332023-11-27027 November 2023 ISFSI Tribal Letter to Yak Tityu Tityu Northern Chumash Indians ML23307A0062023-11-27027 November 2023 ISFSI Tribal Letter to Northern Chumash Tribal Council ML24003A7242023-11-27027 November 2023 Independent Safety Committee; Diab Lo Canyon Nuclear Power Plant Operations, Thirty-Third Annual Report on the Safety ML23325A1292023-11-27027 November 2023 ISFSI Tribal Letter to Coastal Band of Chumash ML23320A1502023-11-17017 November 2023 Individual Notice of Consideration of Issuance of Amendment to Facility Operating License, Proposed No Significant Hazards Consideration Determination, & Opportunity for Hearing (Exigent Circumstances) (EPID L-2023-LLA-0155) - LTR DCL-23-121, Supplement to License Amendment Request 23-03, Revision to Technical Specification3.7.8, Auxiliary Saltwater System2023-11-16016 November 2023 Supplement to License Amendment Request 23-03, Revision to Technical Specification3.7.8, Auxiliary Saltwater System ML23296A0982023-11-15015 November 2023 Notification and Request for Consultation Regarding Pacific Gas and Electric Diablo Canyon Independent Spent Fuel Storage Installation Material License Renewal Request (Docket Number: 72-26) DCL-23-120, License Amendment Request 23-03 Revision to Technical Specification 3.7.8, Auxiliary Saltwater (Asw) System2023-11-14014 November 2023 License Amendment Request 23-03 Revision to Technical Specification 3.7.8, Auxiliary Saltwater (Asw) System ML23293A1052023-11-14014 November 2023 Receipt and Availability of License Renewal Application IR 05000275/20230032023-11-13013 November 2023 Integrated Inspection Report 05000275/2023003 and 05000323/2023003 ML23311A2082023-11-0909 November 2023 Reassignment of U.S. Nuclear Regulatory Commission Branch Chief in the Division of Operating Reactor Licensing for Plant Licensing Branch IV DCL-23-118, License Renewal Application2023-11-0707 November 2023 License Renewal Application ML23318A2102023-10-31031 October 2023 Independent Safety Committee; Thirty-Third Annual Report on the Safety of Diablo Canyon Nuclear Power Plant Operations DCL-2023-520, Discharge Self-Monitoring at Diablo Canyon Power Plant (DCPP)2023-10-19019 October 2023 Discharge Self-Monitoring at Diablo Canyon Power Plant (DCPP) DCL-23-103, Independent Spent Fuel Storage Installation - Withdrawal of License Amendment Request 22-01, Request for Approval of Alternative Security Measures for Early Warning System2023-10-13013 October 2023 Independent Spent Fuel Storage Installation - Withdrawal of License Amendment Request 22-01, Request for Approval of Alternative Security Measures for Early Warning System IR 05000275/20240152023-10-10010 October 2023 Information Request for the Cybersecurity Baseline Inspection, Notification to Perform Inspection (050002752024015 and 050003232024015) 2024-02-09
[Table view] |
Text
July 28, 2021
SUBJECT:
DIABLO CANYON POWER PLANT, UNITS 1 AND 2 - TEMPORARY INSTRUCTION 2515/194 REPORT 05000275/2021012 AND 05000323/2021012
Dear Mr. Welsch:
On June 15, 2021, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Diablo Canyon Power Plant, Units 1 and 2 and discussed the results of this inspection with Ms.
Paula Gerfen and other members of your staff. The results of this inspection are documented in the enclosed report.
No findings or violations of more than minor significance were identified during this inspection.
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 Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding.
Sincerely, Nicholas Digitally signed by Nicholas H. Taylor H. Taylor Date: 2021.07.28 14:34:05 -05'00'
Nicholas H. Taylor, Chief Engineering Branch 2 Division of Reactor Safety Docket Nos. 05000275 and 05000323 License Nos. DPR-80 and DPR-82
Enclosure:
As stated
Inspection Report
Docket Numbers: 05000275 and 05000323 License Numbers: DPR-80 and DPR-82 Report Numbers: 05000275/2021012 and 05000323/2021012 Enterprise Identifier: I-2021-012-0010 Licensee: Pacific Gas and Electric Company Facility: Diablo Canyon Power Plant, Units 1 and 2 Location: Avila Beach, CA Inspection Dates: June 07, 2021 to June 11, 2021 Inspectors: S. Graves, Senior Reactor Inspector D. Loveless, Senior Reactor Analyst Approved By: Nicholas H. Taylor, Chief Engineering Branch 2 Division of Reactor Safety 3 Enclosure
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a Temporary Instruction 2515/194 at Diablo Canyon 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 or violations of more than minor significance were identified.
Additional Tracking Items
None.
INSPECTION SCOPES
Inspections were conducted using the appropriate portions of the Temporary Instruction (TI) in effect at the beginning of the inspection unless otherwise noted. Currently approved Inspection Procedures (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 TI 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. Starting on March 20, 2020, in response to the National Emergency declared by the President of the United States on the public health risks of the coronavirus (COVID-19),inspectors were directed to begin telework. In addition, regional baseline inspections were evaluated to determine if all or a portion of the objectives and requirements stated in the IP could be performed remotely. If the inspections could be performed remotely, they were conducted per the applicable IP. In some cases, portions of an IP were completed remotely and on site. The inspections documented below met the objectives and requirements for completion of this TI.
OTHER ACTIVITIES
- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL 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 inspectors reviewed the licensees implementation of Revision 3 to the Nuclear Energy Institute Industry Initiative on Open Phase Condition, (ADAMS Accession No. ML19163A176)dated June 6, 2019. This review included the licensee's application of risk screening techniques to determine that the risk associated with an open phase condition (OPC) event is significantly reduced through the implementation of detection circuits and the use of operator manual actions in lieu of automatic trip functions. The inspectors also reviewed the updates to the DCPP licensing basis to reflect the need to protect against open phase conditions.
Inspection of the Licensees Implementation of Industry Initiative Associated With the Open Phase Condition Design Vulnerabilities In Electric Power Systems (NRC Bulletin 2012-01) (1 Sample)
- (1) Inspection of the Licensees Implementation of Industry Initiative Associated With the Open Phase Condition Design Vulnerabilities In Electric Power Systems (NRC Bulletin 2012-01) (1 Sample)
Pacific Gas and Electric Company (PG&E) had selected the open phase detection system designed and manufactured by Power System Sentinel Technologies, LLC, (PSSTech) as the design vendor for Diablo Canyon Power Plant (DCPP). The licensee had installed dual-channel open phase detection systems on the 500-kV main transformer banks for both Unit 1 and 2, as well as on the Standby Startup 230-kV transformers for both units. In total, the licensee installed eight PSSTech open phase detection systems on four transformers.
During normal operation each unit generates and delivers power to the 500-kV transmission system via the main transformer banks. Each transformer bank has three single-phase transformers connected in a grounded-Wye primary and Delta secondary configuration. Each units main generator also provides power to the unit auxiliary loads through two auxiliary transformers (Delta configured primary windings). During periods in which the main generator is offline, such as outages, the unit main transformers can be manually realigned in a backfeed configuration. This configuration can also be used to provide offsite power to the unit if the preferred offsite source is unavailable. The licensee identified that this backfeed configuration was susceptible to open phase conditions and installed open phase detection using the common neutral connection to mitigate this condition.
The licensee also installed open phase detection systems on each units Standby Startup transformers. Each unit has a 230-kV/12-kV transformer (SUT11, SUT21) connected in a grounded-Wye/Delta configuration. These transformers are part of the preferred offsite power supply and during off-normal conditions supply offsite power to the units startup and vital loads.
As part of the licensee's implementation of Revision 3 to the open phase initiative, the licensee used contractor services to model and evaluate the effects of open phase conditions (OPCs) on the DCPP electrical distribution system and ESF/PRA-credited loads. The inspectors reviewed the contractor's report and assumptions, and discussed the distribution system behavior under various open-phase scenarios with licensee staff, including the use of existing 51N neutral overcurrent relaying and pilot wire differential protection relaying as protective elements in the licensee's OPC mitigating strategy. The inspectors noted that the 4.16-kV ESF motor circuit breaker protective relays did not use a seal-in function for overcurrent trips, allowing the motors to be reset and restarted from both the local control and the control room. The circuit breakers have an anti-pump feature which prevents the circuit breakers from immediately reclosing onto a fault.
INSPECTION RESULTS
Observation: Temporary Instruction 2515/194-03.01 - Voluntary Industry Initiative 2515/194 Based on discussions with DCPP staff, review of design and testing documentation, and walkdowns of installed equipment, the inspectors had reasonable assurance that PG&E is appropriately implementing the voluntary industry initiative at DCPP. The inspectors verified the following criteria:
Detection, Alarms and General Criteria 1. [03.01(a)(1)] Open phase conditions are detected and alarmed in the control room.
2. [03.01(a)(2)] In scenarios where automatic detection may not be possible due to very low or no load conditions, or when transformers are in a standby mode, automatic detection will occur as soon as loads are transferred to the standby source.
Additionally, where automatic detection is not reliable, PG&E has established monitoring requirements on a per shift basis, to look for evidence of an open phase condition.
3. [03.01(a)(4)] No Class 1E circuits were being replaced with non-Class 1E circuits in this design.
4. [03.01(a)(5)] The Final Safety Analysis Report was updated to discuss the design features and analyses related to the effects of any open phase condition design vulnerability.
5. [03.01(a)(6)] The open phase condition detection and alarm components are
maintained in accordance with PG&E procedures or maintenance program, and periodic tests, calibrations setpoint verifications or inspections (as applicable) have been established. The open phase equipment is covered under the licensees maintenance rule requirements.
Use of Risk-Informed Evaluation Method 1. [03.01(c)(1)] The plant configuration matched the changes made to the probabilistic risk assessment model to address an open phase condition, and the logic of the probabilistic risk assessment model changes is sound.
2. [03.01(c)(2)] The procedures which validate that the open phase condition alarm would identify the proper indication to validate the open phase conditions at all possible locations.
3. [03.01(c)(3)] Observations associated with procedure(s) and operator actions required to respond to an open phase condition alarm and potential equipment trip match the Human Reliability
Analysis.
4. [03.01(c)(4)] Assumptions listed in the NEI 19-02 Appendix A evaluation and the
sensitivity analyses listed in Section 5 of the evaluation were verified.
5. [03.01(c)(5)] Assumptions, procedures, operator actions, and PG&E analyses specified above are consistent with the plant-specific design and licensing basis, including:
a. Initiating events considered in the analysis b. Boundary conditions specified in Attachment 1 of the NEI Voluntary Industry Initiative, Revision 3 c. Operating procedures for steps taken to recover equipment from the effects of open phase conditions (or use of alternate equipment) was appropriate.
d. Where recovery was assumed in the probabilistic risk assessment analysis for tripped electric equipment, restoration of the equipment was based on analyses that demonstrate that automatic isolation trips did not result in equipment damage No findings or exceptions were identified.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On June 15, 2021, the inspectors presented the Exit Meeting inspection results to Ms.
Paula Gerfen, Site Vice President, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection Type Designation Description or Title Revision or
Procedure Date
2515/194 Calculations20-064 Diablo Canyon Power Plant Open Phase Analysis (Zachry) 0
PRA 19-07 Risk Impacts of the Open Phase Condition at DCPP 3
PRA 19-07 Risk Impacts of the Open Phase Condition at DCPP 2
Corrective Action SAPN 50304396, 51073848, 51080145, 51091117, 51091286,
Documents 51094821, 51102249, 51110258, 51118174, 51118204,
51122198, 51122347
Corrective Action SAPN 51122198
Documents
Resulting from
Inspection
Drawings 437530, Sheet 1 Electrical Single Line Meter & Relay Diagram 12KV Start-Up 41
System
437531, Sheet 1 Electrical Single Line Meter and Relay Diagram 12KV 28
System
437532, Sheet 1 Unit 1 Electrical Single Line Meter & Relay Diagram 4160 29
Volt System
437595, Sheet 1 Electrical Schematic Diagram Charging Pumps No. 11 & 12 33
437618, Sheet 1 Electrical Schematic Diagram Stand By Start-Up Transformer 34
No. 11 And Associated Circuit Breakers
437619, Sheet 1 Electrical Schematic Diagram StandBy Start-Up Transformer 31
No. 11 And Associated Circuit Breakers
500790, Sheet 1 Electrical Schematic Diagram Main Annunciator Windows 43
PK2013 - PK2025
500808, sheet 1 Electrical Arrangement of Main Annunciator Window 75
501140, Sheet 1 Electrical Schematic Diagram Main Annunciator Windows 55
PK2013 - PK2025
2110, Sheet 1 Electrical Single Line Diagram 500/230/25/12/4.16KV 22
Systems
57554, Sheet 1 Electrical Cable Tray and Conduit Layout Plan Below Elev. 34
140' - 0" Area "A"
57568, Sheet 1 Electrical Cable Tray and Conduit Layout Plan Below Elev. 66
107' - 0" Area "A"
Enclosure
Inspection Type Designation Description or Title Revision or
Procedure Date
Miscellaneous 230kV Open Phase Simulator Scenario NA
DCP 1000025547 UFSAR Change Request - Section 8. 2. 3. 2. 2. 4, Operation 0
REV 0 During Severe Grid Disturbances Analysis
ATTACHMENT 8
Procedures AR PK20-19 Unit 1 Annunciator Response 230 KV Open Phase 11
AR PK20-19 Unit 2 Annunciator Response 230 KV Open Phase 4
AR PK20-24 Unit 1 Annunciator Response 230 KV SWYD 15
AR PK20-24 Unit 2 Annunciator Response 230 KV SWYD 8
EOP ECA-0.3 Unit 1 Restore 4kV Buses 24
MP E-50.46ST SUT Open Phase Detection Relay Maintenance and Testing 1
MP E-50.46ST.1 SUT Open Phase Detection Relay Data Acquisition 3
MP E- Main Bank Transformer (MBT) Open Phase Detection Relay 0
50.46TGM.2 Channel Reference
OP J-2:XII Unit 2 230kV Open Phase Protection System Operation 4
OP J-2:XII Unit 1 230kV Open Phase Protection System Operation 4
Self-Assessments Temporary Instruction (TI) 2515/194 Open Phase Condition
Design Vulnerabilities in Electric Power Systems Inspection
Date June 8, 2021 SAPN 51105830
Enclosure