Between January 16 and February 13, 2017, a power supply that supports operation of one of two ventilation supply fans for the 2A Emergency Diesel Generator ( EDG) failed. Vogtle Electric Generating Plant ( VEGP) Technical Specifications (TS), 3.8.3 Condition F requires restoration of the fan within 14 days or the EDG must be declared inoperable. This condition was not identified by operators because there is no failure indication. Therefore, the power supply was not repaired within the required time. The EDG should have been declared inoperable and TS 3.8.1. Condition B entered.
Subsequently the completion time for TS 3.8.1 Condition B expired and the unit should have been shut down. This action was not taken and Unit 2 operated in a condition prohibited by TS.
Between February 13 and February 22, 2017, the second power supply failed on this EDG resulting in the second ventilation supply fan being inoperable. Since no failure indication is available, this condition was not identified by the operators. The TS 3.8.3 action for two power supplies inoperable is to immediately declare the EDG inoperable.
Subsequently, the completion time expired and the unit operated in a condition prohibited by TS. During a monthly surveillance run on March 8, both power supplies were discovered failed. Both power supplies were replaced on March 9, 2017 and the EDG was declared operable. |
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Category:Letter
MONTHYEARML24032A0252024-02-0505 February 2024 NRC Initial Test Program and Operational Programs Integrated Inspection Report 05200026-2023009 ML24010A0712024-01-31031 January 2024 Exemption from Select Requirements of 10 CFR Part 73 (Security Notifications, Reports and Recordkeeping and Suspicious Activity Reporting) ML24031A6102024-01-31031 January 2024 Cyber Security Inspection Report 05200026/2024401 - Public ML24029A0592024-01-30030 January 2024 Request for Withholding Information from Public Disclosure Responses to NRC Request for Additional Information for Refueling Outage 1R24 Steam Generator Tube Inspection Report Enclosure 2, GAE-NRCD-RF-LR-000002 P-Attachment, Rev. 0 ML24016A1132024-01-30030 January 2024 Correction of Unit 1 Amendment Nos. 96 and 190 and Unit 2 Amendment Nos. 74 and 173 Adoption of Standard Technical Specifications Westinghouse Plants NL-24-0031, Inservice Inspection Program Owner'S Activity Report (OAR-1) for Outage 2R232024-01-29029 January 2024 Inservice Inspection Program Owner'S Activity Report (OAR-1) for Outage 2R23 IR 05000424/20244032024-01-26026 January 2024 Information Request for the Cyber-Security Baseline Inspection, Notification to Perform Inspection 05000424/2024403; 05000425/2024403 NL-24-0020, Plan, Unit 1 Responses to NRC Request for Additional Information for Refueling Outage 1R24 Steam Generator Tube Inspection Report2024-01-22022 January 2024 Plan, Unit 1 Responses to NRC Request for Additional Information for Refueling Outage 1R24 Steam Generator Tube Inspection Report ML23347A2092024-01-17017 January 2024 Voluntary Requests for Data, Information, And/Or Observation ML23279A0042024-01-17017 January 2024 Amendment No. 194 to Remove Combined License Appendix C NL-23-0926, Correction of Technical Specification Typographical Error2024-01-12012 January 2024 Correction of Technical Specification Typographical Error ML23341A2042024-01-12012 January 2024 Request for Additional Information Exemption Requests for Physical Barriers (EPID L-2023-LLE-0018 & L-2023-LLE-0021) ML23345A1312024-01-0303 January 2024 Withholding Letter - SNC Fleet - Physical Barriers Exemption (L-2023-LLE-0018 and L-2023-LLE-0021) ML23317A2072023-12-22022 December 2023 Issuance of Amendments 223 and 206 Regarding Revision to Technical Specifications to Adopt TSTF-339-A, Relocate Technical Specification Parameters to the COLR Consistent with WCAP-1448 ML23335A1222023-12-19019 December 2023 Safety Evaluation Regarding Implementation of Mitigating Strategies Related to Order EA-12-049 (EPID L-2023-LRQ-0002) - Letter ML23353A1702023-12-19019 December 2023 LAR-22-002, TS 3.8.3 Inverters Operating Completion Time Extension Letter ML23310A2922023-12-0707 December 2023 Issuance of Amendment for Exception to Regulatory Guide 1.163, LAR 23 007 ML23339A1812023-12-0707 December 2023 Correction Letter Regarding License Amendment Request: More Restrictive Action for Technical Specification 3.1.9 ML23338A2182023-12-0606 December 2023 Project Manager Reassignment NL-23-0878, Request for Exemption from Security Event Notification Implementation2023-11-29029 November 2023 Request for Exemption from Security Event Notification Implementation ML23289A1632023-11-28028 November 2023 Letter and Amendment 195 and 192 LAR-23-006R1 TS 3.1.9 More Restrictive Action NL-23-0827, Response to Requests for Additional Information for a License Amendment Request and a Proposed Alternative Related to TS 3.4.142023-11-17017 November 2023 Response to Requests for Additional Information for a License Amendment Request and a Proposed Alternative Related to TS 3.4.14 ML23318A4582023-11-14014 November 2023 Integrated Inspection Report 05200025/2023003 ML23312A3502023-11-14014 November 2023 Integrated Inspection Report 05200026/2023003 ML23306A3552023-11-0808 November 2023 NRC Initial Test Program and Operational Programs Integrated Inspection Report 052000/262023008 ML23268A0572023-11-0707 November 2023 Issuance of Amendments 194 & 191 Request for License Amendment Relocation of Technical Specification 3.7.9, Spent Fuel Pool Makeup Water Sources (LAR-23-003) IR 05000424/20234022023-11-0606 November 2023 Security Baseline Inspection Report 05000424/2023402 and 05000425/2023402 IR 05000424/20230032023-10-27027 October 2023 Integrated Inspection Report 05000424/2023003 and 05000425/2023003 ML23291A1512023-10-18018 October 2023 Information Request for the Cyber Security Baseline Inspection, Notification to Perform Inspection 0520026/2024401 ML23263A9852023-10-12012 October 2023 Issuance of Amendments Nos. 221 and 204, Regarding Technical Specification 5.5.11.C, Acceptance Criteria for Charcoal Filter Testing ML23283A0472023-10-0808 October 2023 Neop Letter Dated October 8, 2023 - Vogtle 3 & 4 - TS 3.7.6 License Amendment Request NL-23-0750, Response to Second Request for Additional Information Regarding License Amendment Request: Technical Specification Revision to Adopt TSTF-339-A, Relocate Technical Specification Parameters to the Colr2023-10-0404 October 2023 Response to Second Request for Additional Information Regarding License Amendment Request: Technical Specification Revision to Adopt TSTF-339-A, Relocate Technical Specification Parameters to the Colr NL-23-0745, Refueling Outage 1R24 Steam Generator Tube Inspection Report2023-09-22022 September 2023 Refueling Outage 1R24 Steam Generator Tube Inspection Report ML23254A2032023-09-13013 September 2023 Initial Test Program and Operational Programs Inspection Report 05200025/2023013 ML23241B0212023-09-12012 September 2023 Review of Quality Assurance Topical Report ML23234A2352023-09-0808 September 2023 Request for Withholding Information from Public Disclosure Notification of Full Compliance of Required Action for NRC Order EA-12-049 Mitigation Strategies for Beyond-Design-Basis External Events IR 05000424/20230912023-09-0505 September 2023 Plan Units 1 and 2 - NRC Investigation Report 2-2022-006 and Notice of Violation - NRC Inspection Report 05000424/2023091 and 05000425/2023091 ML23234A3002023-09-0101 September 2023 NRC Integrated Inspection Report 05200026/2023003 ML23243A0092023-08-31031 August 2023 Updated Inspection Plan for Vogtle Electric Generating Plant, Units 3 & 4 (Report 05200025 2023005 & 05200026 2023005) NL-23-0695, Response to Round 2 Request for Additional Information Regarding License Amendment Request for Technical Specification 3.8.3, Inverters Operating, Completion Time Extension (LAR-22-002S2)2023-08-31031 August 2023 Response to Round 2 Request for Additional Information Regarding License Amendment Request for Technical Specification 3.8.3, Inverters Operating, Completion Time Extension (LAR-22-002S2) ML23243B0252023-08-30030 August 2023 Exam Corporate Notification Letter (210 Day) IR 05000424/20230052023-08-29029 August 2023 Updated Inspection Plan for Vogtle Electric Generating Plant, Units 1 & 2 - Report 05000424/2023005 and 05000425/2023005 NL-23-0666, License Amendment Request: Remove Combined License Appendix C (LAR 23-008)2023-08-28028 August 2023 License Amendment Request: Remove Combined License Appendix C (LAR 23-008) 2024-02-05
[Table view] Category:Licensee Event Report (LER)
MONTHYEARND-23-0439, ITAAC Closure Notification on Completion of ITAAC 2.2.05.07a.i (Index Number 265)2023-07-18018 July 2023 ITAAC Closure Notification on Completion of ITAAC 2.2.05.07a.i (Index Number 265) 05000425/LER-2017-0022017-11-17017 November 2017 Valid Undervottage Condition results in Automatic Actuation of a Safety System, LER 17-002-00 for Vogtle, Unit 2, Regarding Valid Undervoltage Condition Results in Automatic Actuation of a Safety System 05000424/LER-2017-0022017-06-29029 June 2017 Vice President Vogtle Units 1-2 7821 River RD Waynesboro GA, 30830 706-848-0004 tel 706-848-3321 fax June 29, 2017 Docket No: 50-424 NL-17-1104 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Vogtle Electric Generating Plant — Unit 1 Licensee Event Report 2017-002-01 Wiring Error results in Automatic Actuation of a Safety System Ladies and Gentlemen: In accordance with the requirements of 10 CFR 50.73(a)(2)(iv)(A), Southern Nuclear Operating Company is submitting the enclosed Licensee Event Report, 2017-002-01 for Vogtle Electric Generating Plant Unit 1. This letter contains no NRC commitments. If you have any questions, please contact Dom Sutton at (706) 848-1428. Respectfully sub Darin J. M rs Vice President — Plant ogtle Units 1&2 - SNC DJM/KCW Enclosure: Unit 1 Licensee Event Report 2017-002-01 Cc: Regional Administrator NRR Project Manager — Vogtle 1 & 2 Senior Resident Inspector — Vogtle 1 & 2 RType: CVC7000 Vogtle Electric Generating Plant — Unit 1 Licensee Event Report 2017-002-01 Wiring Labeling Error results in Automatic Actuation of a Safety System Enclosure Unit 1 Licensee Event Report 2017-002-01 NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (04-2017) LICENSEE EVENT REPORT (LER) ILWa t l,viricir (See Page 2 for required number of digits/charactersfor each block) ••••••• (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.qovireadincl-rmidoc-collections/nuregs/staff/sr1022/r3i) APPROVED BY OMB: NO. 3150-0104 EXPIRES: 0313112020 Estimated burden per response to comply with this mandatory collection request: 80 hours Reported lessons learned are incorporated into the licensing process and fed back to industry Send comments regarding burden estimate to the Information Services Branch (T-2 F43), US Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to Infocollects Resource@nrc gov, and to the Desk Officer, Office of Information •and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington. DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection. 1. FACILITY NAME Vogtle Electric Generating Plant . DOCKET NUMBER 13. PAGE 17.:15000424 1 1 OF 2 4. TITLE Mirina Error results in_AulomaticActuation_of a Safety System_, LER 17-002-01 for Vogtle, Unit 1, Wiring Error Results in Automatic Actuation of a Safety System 05000425/LER-2017-0012017-06-29029 June 2017 1 OF 3, LER 17-001-01 for Vogtle, Unit 2, Regarding Power Supply Failure Results in Operation in a Condition Prohibited by Technical Specifications Supplement NL-10-0577, LER 10-S01-00 for Vogtle, Units 1 & 2 Regarding Supplemental Worker'S Unescorted Access Not Revoked in a Timely Manner2010-03-30030 March 2010 LER 10-S01-00 for Vogtle, Units 1 & 2 Regarding Supplemental Worker'S Unescorted Access Not Revoked in a Timely Manner 2023-07-18
[Table view] |
Infocollects Resource@nrc.goy and to the Desk Officer Office of Information and Regulatory Affairs NEOB-10202 (3150-0104) Office of Management and Budget Washington DC 20503 If a means used to impose an information cm'ection does not display a currently valid OMB contra number the NRC may not conduct or sporsor and a person is not required to respond to the nformation collection Vogtle Electric Generating Plant 05000-425 2017
SEQUENT AL
- 001
NO
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A. Event Description
On March 15, 2017 during a review of past events with the Unit 2 A-Train Emergency Diesel Generator (EDG)[DG], it was discovered that a power supply that supports the "B" ventilation supply fan NJ] failed between the diesel run on January 16, 2017 and February 13, 2017. The EDG has two power supplies supporting a common speed sensing circuit and one ventilation fan each. The EDG can successfully operate with one power supply supporting the speed sensing circuit. The "A" ventilation fan immediately starts upon EDG start. The "B. ventilation fan enters stand-by on EDG start and operates once thermostat temperature reaches 93F. Per Vogtle TS 3.8.3 Condition F, if a ventilation supply fan is not operable, the fan must be restored operable within 14 days or the associated EDG must be declared inoperable. This restoration time was not met as the condition was not identified by operators because no indication is available to reveal the failure while the EDG is in standby. Per TS 3.8.3, Condition G, operators should have declared the associated EDG inoperable on February 27, 2017 and entered TS 3.8.1.
Condition B. TS 3.8.1 Condition B allows a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> completion time for verification of certain electrical parameters and if these are not completed, Condition C is entered, which is a 72-hour shutdown action. Because it was not recognized that the power supply was failed, these actions were not taken and the plant operated in a condition prohibited by TS from the time the power supply failed until the power supply was replaced on March 9, 2017.
Subsequently, between February 13 and February 22, 2017, the second power supply failed resulting in both ventilation supply fans being inoperable. This condition was also not identified by the operators due to no indication being available to reveal the failure. The TS required action for this condition (TS 3.8.3 Condition G) is to immediately declare the associated EDG inoperable. Declaration by the operators of the 2A EDG inoperable per TS 3.8.1 Condition B would have allowed a 1-hour completion time for verification of certain electrical parameters and if these are not completed, Condition C is entered, which is a 72-hour shutdown action. Because it was not recognized that these power supplies were failed, these actions were not taken and the plant operated in a condition prohibited by TS.
On March 8, the 2A EDG was started for a monthly surveillance; however, normal start indications were not working and the operators shut down the EDG and declared it inoperable. During troubleshooting, the two power supplies were found failed and both were replaced March 9, 2017. Once the work was complete, the 2A EDG ran successfully.
The power supplies on the B-Train EDG and the Unit 1 EDGs were checked and none of them were failed.
The unit operated in Mode 1 at 100 percent power during the entire time of these events.
Because the unit operated in a condition prohibited by Technical Specifications, these events are reportable as required by 10 CFR 50.73(a)(2)(i)(B).
B. Cause of Event
The cause of the operation in a condition prohibited by TS was a failure to recognize that the power supply had failed and rendered the ventilation supply fans inoperable. The reason for the failure of the power supplies has been attributed to random voltage spikes on the DC bus. The most likely cause is the battery charger on the circuit.
C. Safety Assessment During the first condition prohibited by Tech Specs, the EDG was able to start and load its associated safety related electrical bus because the second power supply was still available. As discussed in the Tech Spec Bases.
except in extreme temperatures, only one fan is needed to keep the temperature in the EDG room below the limit of 120F. During the time that this fan was inoperable, the outside temperatures remained well below the 93F limit for single fan operation as listed in the TS Bases. Because the EDG could perform its required safety function during this time, the safety significance of this event was very low.
For the second condition prohibited by Tech Specs, the EDG would have started but would not have automatically loaded the electrical bus due to an electrical permissive from the speed sensing circuit powered by the failed power supplies. During this time, the opposite train EDG was fully operable and both power supplies were verified comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission. Washington, DC 213555-0001. or by e-mail to used to impose an information coPection does rot display a currently valid OMB control number, the NRC may not conduct or sponsor and a person is not required to respond to, the information collection 2 DOCKET NUMBER 3. LER NUMBER 1. FACILITY NAME Vogtle Electric Generating Plant 05000-425 2017 - 001 - 01 to be operational. This would have allowed an electrical safety bus to be powered during an accident. Additionally, all required offsite electrical sources were available and the combustion turbines with blackstart capabilities, adequate fuel, along with the associated underground power line at Plant Wilson were available and were within their required reliability parameters. These capabilities were determined well after the condition occurred and the diesel was repaired. The capabilities of other electrical sources were not evaluated during the period of inoperability. However, with these additional measures available for supplying the safety related electrical bus, the safety significance of this event was very low.
D. Corrective Actions
Both power supplies for the 2A EDG were replaced when it was recognized that they were failed. The "A" battery charger that was in service upstream of these power supplies during all the failures was taken out of service and the "B" battery charger was put into service. During a recent 2A EDG maintenance period, the "A" battery charger was rebuilt and components sent off for failure analysis. Lastly, there is continuous monitoring of the DC bus looking for random voltage spikes. None have been detected since the monitoring was put into place.
E. Previous Similar Events:
None
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05000425/LER-2017-001 | 1 OF 3 LER 17-001-01 for Vogtle, Unit 2, Regarding Power Supply Failure Results in Operation in a Condition Prohibited by Technical Specifications Supplement | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000425/LER-2017-002 | Valid Undervottage Condition results in Automatic Actuation of a Safety System LER 17-002-00 for Vogtle, Unit 2, Regarding Valid Undervoltage Condition Results in Automatic Actuation of a Safety System | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000424/LER-2017-002 | Vice President Vogtle Units 1-2 7821 River RD Waynesboro GA, 30830 706-848-0004 tel 706-848-3321 fax June 29, 2017 Docket No: 50-424 NL-17-1104 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Vogtle Electric Generating Plant — Unit 1 Licensee Event Report 2017-002-01 Wiring Error results in Automatic Actuation of a Safety System Ladies and Gentlemen: In accordance with the requirements of 10 CFR 50.73(a)(2)(iv)(A), Southern Nuclear Operating Company is submitting the enclosed Licensee Event Report, 2017-002-01 for Vogtle Electric Generating Plant Unit 1. This letter contains no NRC commitments. If you have any questions, please contact Dom Sutton at (706) 848-1428. Respectfully sub Darin J. M rs Vice President — Plant ogtle Units 1&2 - SNC DJM/KCW Enclosure: Unit 1 Licensee Event Report 2017-002-01 Cc: Regional Administrator NRR Project Manager — Vogtle 1 & 2 Senior Resident Inspector — Vogtle 1 & 2 RType: CVC7000 Vogtle Electric Generating Plant — Unit 1 Licensee Event Report 2017-002-01 Wiring Labeling Error results in Automatic Actuation of a Safety System Enclosure Unit 1 Licensee Event Report 2017-002-01 NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (04-2017) LICENSEE EVENT REPORT (LER) ILWa t l,viricir (See Page 2 for required number of digits/charactersfor each block) ••••••• (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.qovireadincl-rmidoc-collections/nuregs/staff/sr1022/r3i) APPROVED BY OMB: NO. 3150-0104 EXPIRES: 0313112020 Estimated burden per response to comply with this mandatory collection request: 80 hours Reported lessons learned are incorporated into the licensing process and fed back to industry Send comments regarding burden estimate to the Information Services Branch (T-2 F43), US Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to Infocollects Resource@nrc gov, and to the Desk Officer, Office of Information •and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington. DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection. 1. FACILITY NAME Vogtle Electric Generating Plant . DOCKET NUMBER 13. PAGE 17.:15000424 1 1 OF 2 4. TITLE Mirina Error results in_AulomaticActuation_of a Safety System_ LER 17-002-01 for Vogtle, Unit 1, Wiring Error Results in Automatic Actuation of a Safety System | 10 CFR 50.73(a)(2)(iv)(A), System Actuation |
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