Similar Documents at Byron |
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Category:Inspection Report
MONTHYEARIR 05000454/20240112024-08-0808 August 2024 Phase 2 Post- Approval License Renewal Report 05000454/2024011 IR 05000454/20240022024-07-26026 July 2024 Integrated Inspection Report 05000454/2024002 and 05000455/2024002, and Exercise of Enforcement Discretion IR 05000454/20240012024-05-10010 May 2024 Integrated Inspection Report 05000454/2024001; 05000455/2024001 and 07200068/2024001 IR 05000454/20244012024-04-0303 April 2024 Cyber Security Inspection Report 05000454/2024401 and 05000455/2024401 (Public) IR 05000454/20230042024-02-0202 February 2024 Integrated Inspection Report 05000454/2023004 and 05000455/2023004 IR 05000454/20233012023-11-27027 November 2023 NRC Initial License Examination Report 05000454/2023301 and 05000455/2023301 IR 05000454/20230032023-11-13013 November 2023 Integrated Inspection Report 05000454/2023003 and 05000455/2023003 and Exercise of Enforcement Discretion ML23251A1622023-09-29029 September 2023 Steam Generator Tube Inspection Reports to Reflect TSTF-577 Reporting Requirements IR 05000454/20235012023-08-31031 August 2023 Emergency Preparedness Biennial Exercise Inspection Report 05000454/2023501 and 05000455/2023501 IR 05000454/20230052023-08-30030 August 2023 Updated Inspection Plan for Byron Station (Report 05000454/2023005 and 05000455/2023005) IR 05000454/20230022023-08-0303 August 2023 Integrated Inspection Report 05000454/2023002 and 05000455/2023002 IR 05000454/20234022023-07-18018 July 2023 Baseline Security Inspection Document; 05000454/2023402; 05000455/2023402 IR 05000454/20230012023-05-0505 May 2023 Integrated Inspection Report 05000454/2023001 and 05000455/2023001 IR 05000454/20230102023-04-19019 April 2023 License Phase 1 Report 05000454/2023010 IR 05000454/20234012023-03-30030 March 2023 Baseline Security Inspection 05000454/2023401; and 05000455/2023401 IR 05000454/20223012023-03-0707 March 2023 NRC Initial License Examination Report 05000454/2022301 and 05000455/2022301 IR 05000454/20220062023-03-0101 March 2023 Annual Assessment Letter for Byron Station, Units 1 and 2 (Report 05000455/2022006 and 05000454/2022006) IR 05000454/20220042023-02-0101 February 2023 Integrated Inspection Report 05000454/2022004 and 05000455/2022004 IR 05000454/20220102023-01-17017 January 2023 Design Basis Assurance Inspection (Programs) Inspection Report Report 05000454/2022010 and 05000455/2022010 IR 05000454/20224032022-12-28028 December 2022 Cyber Security Inspection Report 05000454/2022403 and 05000455/2022403 IR 05000454/20224052022-12-0909 December 2022 Material Control and Accounting Program Inspection Report 05000454/2022405 and 05000455/2022405 IR 05000454/20220032022-11-0707 November 2022 Integrated Inspection Report 05000454/2022003 and 05000455/2022003 BYRON 2022-0072, Steam Generator Tube Inspection Report for Refueling Outage 232022-10-27027 October 2022 Steam Generator Tube Inspection Report for Refueling Outage 23 IR 05000454/20220052022-08-24024 August 2022 Updated Inspection Plan for Byron Station Units 1 and 2 (Report 05000454/2022005; 05000455/2022005) IR 05000454/20224022022-08-0909 August 2022 Security Baseline Inspection Report 05000454/2022402 and 05000455/2022402 IR 05000454/20220022022-08-0808 August 2022 Integrated Inspection Report 05000454/2022002 and 05000455/2022002 IR 05000454/20220012022-05-0303 May 2022 Integrated Inspection Report 05000454/2022001 and 05000455/2022001 IR 05000454/20224012022-04-0404 April 2022 Security Baseline Inspection Report 05000454/2022401 and 05000455/2022401 IR 05000454/20210062022-03-0202 March 2022 Annual Assessment Letter for Byron Station, Units 1 and 2 (Report 05000454/2021006 and 05000455/2021006) IR 05000454/20210042022-02-11011 February 2022 Integrated Inspection Report 05000454/2021004 and 05000455/2021004 IR 05000454/20210122022-01-0606 January 2022 Biennial Problem Identification and Resolution Inpsection Report 05000454/2021012 and 05000455/2021012 IR 05000454/20213012021-12-17017 December 2021 NRC Initial License Examination Report 05000454/2021301; 05000455/2021301 IR 05000454/20214032021-11-22022 November 2021 Security Baseline Inspection Report 05000454/2021403 and 05000455/2021403 IR 05000454/20210032021-10-29029 October 2021 Integrated Inspection Report 05000454/2021003 and 05000455/2021003 and Exercise of Enforcement Discretion IR 05000454/20214022021-09-28028 September 2021 Security Baseline Inspection Report 05000454/2021402 and 05000455/2021402 IR 05000454/20210052021-09-0101 September 2021 Updated Inspection Plan for Byron Station Units 1 and 2 (05000454/2021005 and 05000455/2021005) IR 05000454/20210022021-08-0404 August 2021 Integrated Inspection Report 05000454/2021002; 05000455/2021002; and 07200068/2021001 IR 05000454/20210112021-05-14014 May 2021 Design Basis Assurance Inspection (Teams) Inspection Report 05000454/2021011 and 05000455/2021011 IR 05000454/20215012021-04-21021 April 2021 Emergency Preparedness Biennial Exercise Inspection Report 05000454/2021501 and 05000455/2021501 IR 05000454/20210012021-04-20020 April 2021 Integrated Inspection Report 05000454/2021001 and 05000455/2021001 IR 05000454/20214012021-03-24024 March 2021 Security Baseline Inspection Report 05000454/2021401 and 05000455/2021401 IR 05000454/20180102021-03-19019 March 2021 Closure of Auxiliary Feedwater System Unresolved Item 05000454/2018010-04 and 05000455/2018010-04 IR 05000454/20200062021-03-0404 March 2021 Annual Assessment Letter for Byron Station (Report 05000454/2020006 and 05000455/2020006) IR 05000454/20210102021-02-0909 February 2021 Triennial Fire Protection Inspection Report 05000454/2021010 and 05000455/2021010 IR 05000454/20200042021-01-27027 January 2021 Integrated Inspection Report 05000454/2020004 and 05000455/2020004 IR 05000454/20204032020-12-16016 December 2020 Security Baseline Inspection Report 05000454/2020403 and 05000455/2020403 IR 05000454/20200032020-11-10010 November 2020 Integrated Inspection Report 05000454/2020003 and 05000455/2020003 IR 05000454/20200112020-09-29029 September 2020 Triennial Inspection of Evaluation of Changes, Tests and Experiments Baseline Inspection Report 05000454/2020011 and 05000455/2020011 IR 05000454/20204022020-09-18018 September 2020 Security Baseline Inspection Report 05000454/2020402 and 05000455/2020402 IR 05000454/20200052020-09-0101 September 2020 Updated Inspection Plan for Byron Station Units 1 and 2 (Report 05000454/2020005 and 05000455/2020005) 2024-08-08
[Table view] Category:Letter
MONTHYEARML24222A6772024-08-0909 August 2024 Response to Request for Additional Information for Application to Revise Technical Specifications to Adopt TSTF-591-A, “Revise Risk Informed Completion Time (RICT) Program” Revision 0 and Revise 10 CFR 50.69 License Condition IR 05000454/20240112024-08-0808 August 2024 Phase 2 Post- Approval License Renewal Report 05000454/2024011 IR 05000454/20240022024-07-26026 July 2024 Integrated Inspection Report 05000454/2024002 and 05000455/2024002, and Exercise of Enforcement Discretion ML24179A3262024-07-23023 July 2024 LTR - Constellation - SG Welds and Nozzles (L-2023-LLR-0053, L-2023-LLR-0054, L-2023-LLR-0055, L-2023-LLR-0056) RS-24-064, Nuclear Radiological Emergency Plan Document Revisions2024-06-28028 June 2024 Nuclear Radiological Emergency Plan Document Revisions RS-24-066, Inservice Testing Interval Extension for Essential Service Water Valves Due to Required Use of Containment Chiller2024-06-25025 June 2024 Inservice Testing Interval Extension for Essential Service Water Valves Due to Required Use of Containment Chiller ML24170A7652024-06-19019 June 2024 Confirmation of Initial License Examination RS-24-061, Constellation Energy Generation, LLC, Response to NRC Regulatory Issue Summary 2024-01, Preparation and Scheduling of Operator Licensing Examinations2024-06-14014 June 2024 Constellation Energy Generation, LLC, Response to NRC Regulatory Issue Summary 2024-01, Preparation and Scheduling of Operator Licensing Examinations RS-24-044, License Amendment to Transition to Framatome Gaia Fuel and Exemptions to 10 CFR 50.46 and 10 CFR 50 Appendix K. Attachments 1 to 11 Enclosed2024-05-28028 May 2024 License Amendment to Transition to Framatome Gaia Fuel and Exemptions to 10 CFR 50.46 and 10 CFR 50 Appendix K. Attachments 1 to 11 Enclosed RS-24-043, Application to Remove Power Distribution Monitoring System (Pdms) Details from Technical Specifications2024-05-24024 May 2024 Application to Remove Power Distribution Monitoring System (Pdms) Details from Technical Specifications ML24142A3352024-05-21021 May 2024 Quad Cities—Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes RS-24-055, 2023 Corporate Regulatory Commitment Change Summary Report2024-05-17017 May 2024 2023 Corporate Regulatory Commitment Change Summary Report BYRON 2024-0031, Completion of License Renewal Activities Prior to Entering the Period of Extended Operation2024-05-16016 May 2024 Completion of License Renewal Activities Prior to Entering the Period of Extended Operation IR 05000454/20240012024-05-10010 May 2024 Integrated Inspection Report 05000454/2024001; 05000455/2024001 and 07200068/2024001 BYRON 2024-0028, Annual Radiological Environmental Operating Report (AREOR)2024-05-0909 May 2024 Annual Radiological Environmental Operating Report (AREOR) BYRON 2024-0022, 2023 Regulatory Commitment Change Summary Report2024-05-0202 May 2024 2023 Regulatory Commitment Change Summary Report RS-24-041, Alternative Request to Utilize Code Case OMN-32, Alternative Requirements for Range and Accuracy of Pressure, Flow, and Differential Pressure Instruments Used in Pump Tests2024-04-30030 April 2024 Alternative Request to Utilize Code Case OMN-32, Alternative Requirements for Range and Accuracy of Pressure, Flow, and Differential Pressure Instruments Used in Pump Tests ML24116A1192024-04-25025 April 2024 2023 Annual Radioactive Effluent Release Report (ARERR) RS-24-026, License Amendment to Braidwood Station, Units 1 and 2, and Byron Station, Units 1 and 2, Technical Specifications 5.6.5, Core Operating Limits Report (COLR)2024-04-25025 April 2024 License Amendment to Braidwood Station, Units 1 and 2, and Byron Station, Units 1 and 2, Technical Specifications 5.6.5, Core Operating Limits Report (COLR) ML24113A1272024-04-22022 April 2024 Audit Plan in Support of Review of LAR Revision of TS 3.7.15, 3.7.16, and 4.3.1 (EPID: L-2023-LLA-0136) (Non-Proprietary) ML24113A2892024-04-22022 April 2024 Notification of NRC Baseline Inspection and Request for Information BYRON 2024-0020, Annual Dose Report for 20232024-04-18018 April 2024 Annual Dose Report for 2023 ML24103A2042024-04-12012 April 2024 Constellation Energy Generation, LLC, Application to Revise Technical Specifications to Adopt TSTF-591-A, Revise Risk Informed Completion Time (RICT) Program Revision 0 and Revise 10 CFR 50.69 License Condition BYRON 2024-0021, Registration of Use of Cask to Store Spent Fuel2024-04-11011 April 2024 Registration of Use of Cask to Store Spent Fuel RS-24-034, Annual 10 CFR 50.46 Report of Emergency Core Cooling System Evaluation Model Changes and Errors2024-04-10010 April 2024 Annual 10 CFR 50.46 Report of Emergency Core Cooling System Evaluation Model Changes and Errors IR 05000454/20244012024-04-0303 April 2024 Cyber Security Inspection Report 05000454/2024401 and 05000455/2024401 (Public) RS-24-002, Constellation Energy Generation, LLC - Annual Property Insurance Status Report2024-04-0101 April 2024 Constellation Energy Generation, LLC - Annual Property Insurance Status Report BYRON 2024-0019, Registration of Use of Cask to Store Spent Fuel2024-03-28028 March 2024 Registration of Use of Cask to Store Spent Fuel RS-24-024, Response to Request for Additional Information Regarding Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds2024-03-22022 March 2024 Response to Request for Additional Information Regarding Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds IR 05000454/20230042024-02-0202 February 2024 Integrated Inspection Report 05000454/2023004 and 05000455/2023004 ML24022A2722024-01-23023 January 2024 Request for Information for an NRC Post-Approval Site Inspection for License Renewal Inspection Report 05000454/2024011 ML24018A0362024-01-17017 January 2024 Paragon Energy Solutions, Defect with Detroit Diesel/Mtu Fuel Injectors P/N R5229660 Cat Id 0001390618 ML23320A1762023-12-13013 December 2023 Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0027 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting)) ML23277A0032023-12-11011 December 2023 Issuance of Amendments Regarding Adoption of TSTF-370 ML23318A5102023-12-0101 December 2023 Relief from the Requirements of the ASME Code IR 05000454/20233012023-11-27027 November 2023 NRC Initial License Examination Report 05000454/2023301 and 05000455/2023301 BYRON 2023-0065, Unit 2 - Notification of Deviation from Electric Power Research Institute (EPRI) Topical Report MRP-227, Revision 1-A, Materials Reliability Program: Pressurized Water Reactor Internals Inspection and Evaluation Guideline2023-11-17017 November 2023 Unit 2 - Notification of Deviation from Electric Power Research Institute (EPRI) Topical Report MRP-227, Revision 1-A, Materials Reliability Program: Pressurized Water Reactor Internals Inspection and Evaluation Guideline BYRON 2023-0063, Day Inservice Inspection Report for Interval 4, Period 3, (B2R24)2023-11-16016 November 2023 Day Inservice Inspection Report for Interval 4, Period 3, (B2R24) IR 05000454/20230032023-11-13013 November 2023 Integrated Inspection Report 05000454/2023003 and 05000455/2023003 and Exercise of Enforcement Discretion ML23317A1192023-11-10010 November 2023 Constellation Energy Generation, LLC - 2023 Annual Report - Guarantees of Payment of Deferred Premiums RS-23-117, Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information2023-11-10010 November 2023 Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information ML23313A0852023-11-0909 November 2023 Submittal of 2023-301 Byron Initial License Examination Post-Examination Comments RS-23-114, Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds2023-11-0101 November 2023 Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds ML23297A2352023-10-26026 October 2023 Information Request for the Cyber Security Baseline Inspection, Notification to Perform Inspection RS-23-100, Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation2023-10-13013 October 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation RS-23-097, Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans2023-10-12012 October 2023 Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans RS-23-108, Proposed Alternative for Examinations of Examination Categories B-B, B-D, and C-A Steam Generator Pressure Retaining Welds and Full Penetration Welded Nozzles2023-10-11011 October 2023 Proposed Alternative for Examinations of Examination Categories B-B, B-D, and C-A Steam Generator Pressure Retaining Welds and Full Penetration Welded Nozzles RS-23-105, Proposed Alternative for Examinations of Examination Category C-B Steam Generator Nozzle-to-Shell Welds and Nozzle Inside Radius Sections2023-10-10010 October 2023 Proposed Alternative for Examinations of Examination Category C-B Steam Generator Nozzle-to-Shell Welds and Nozzle Inside Radius Sections ML23278A0272023-10-0505 October 2023 Operator Licensing Examination Approval - Byron Station, October 2023 RS-23-094, Relief Request I4R-24, Alternative for Post-Peening Reexamination Frequency for Reactor Pressure Vessel Head Penetration Nozzle Number 752023-09-29029 September 2023 Relief Request I4R-24, Alternative for Post-Peening Reexamination Frequency for Reactor Pressure Vessel Head Penetration Nozzle Number 75 2024-08-09
[Table view] |
Inspection Report - Byron - 2008008 |
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Text
May 5, 2008
Mr. Charles Exelon Nuclear Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT: BYRON STATION, UNITS 1 AND 2 FOLLOW UP INSPECTION OF AN UNRESOLVED ITEM (URI) 05000454/2008008; 05000455/2008008
Dear Mr. Pardee:
On March 28, 2008, the U. S. Nuclear Regulatory Commission (NRC) completed an inspection at Byron Station. This report documents the actions taken to review an URI from the 2005 safety systems design, performance and capability inspection at your Byron Station (URI 05000454/2005002-06; URI 05000455/2005002-06). The results were discussed on March 28, 2008, with members of your staff. The inspection examined activities conducted under your license, as they relate to safety and to compliance with the Commission's rules and regulations, and with the conditions of your license. The inspector reviewed selected analyses, and records. Based on the results of this inspection, the NRC identified a concern with respect to the single failure assumptions taken in your ultimate heat sink analyses. In a previous correspondence, you described a less conservative single failure assumption for the ultimate heat sink analysis and that analysis was approved by the agency. After further review, the NRC has determined that a modification is necessary to bring a facility into compliance with the rules or orders of the Commission. Specifically, the passive failures of electrical components need to be postulated to comply with 10 CFR Part 50, Appendix A. The staff assessed this issue as it relates to a backfit and determined that the provisions of 10 CFR 50.109 (a)(4), were applicable, in that, a modification is necessary to bring a facility into compliance with the rules or orders of the Commission. The NRC has also determined that this is not a violation of NRC requirements due to the apparent change in NRC position promulgated by our earlier inaction on your previous correspondence. The circumstances surrounding the issue are described in detail in the subject inspection report. You are requested to respond to this letter with a description of your intended actions to address the noncompliance including a proposed schedule to complete those actions. You have 30 calendar days from the date of this letter to appeal the staff's determination. Such appeals will be considered to have merit only if they meet the criteria given in the NRC Inspection Manual Chapter 0609, Attachment 2. To the extent possible, your response should not include any personal privacy, proprietary, or safeguards information so that it can be made available to the Public without redaction. You should provide a response within 30 days of the date of this inspection report, with your proposed actions or the basis for your appeal, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001, with a copy to the Regional Administrator, U.S. Nuclear Regulatory Commission - Region III, 2443 Warrenville Road, Suite 210, Lisle, IL 60532-4352; the Director, Office of Enforcement, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; and the Resident Inspector Office at the Byron Station Nuclear Plant. In accordance with 10 CFR 2.390 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 NRC Public Document Room or from the Publicly Available Records System (PARS) component of NRC's Agencywide Documents Access and Management System (ADAMS), accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,/RA/ Ann Marie Stone, Chief Engineering Branch 2 Division of Reactor Safety Docket Nos. 50-454; 50-455 License Nos. NPF-37; NPF-66
Enclosure:
Inspection Report No. 05000454/2008008; 05000455/2008008
w/Attachment:
Supplemental Information cc w/encl: Site Vice President - Byron Station Plant Manager - Byron Station Regulatory Assurance Manager - Byron Station Chief Operating Officer and Senior Vice President Senior Vice President - Midwest Operations Senior Vice President - Operations Support Vice President - Licensing and Regulatory Affairs Director - Licensing and Regulatory Affairs Manager Licensing - Braidwood, Byron, and LaSalle Associate General Counsel Document Control Desk - Licensing Assistant Attorney General Illinois Emergency Management Agency J. Klinger, State Liaison Officer, State of Illinois P. Schmidt, State Liaison Officer, State of Wisconsin Chairman, Illinois Commerce Commission B. Quigley, Byron Station
SUMMARY OF FINDINGS
IR 05000454/2008008; 05000455/2008008; March 28, 2008; Byron Station, Units 1 and 2; routine inspection. This report covers a follow up inspection of an unresolved item (URI) by regional inspectors. The NRC's program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, "Reactor Oversight Process," Revision 4, dated December 2006.
A. NRC-Identified
and Self-Revealed Findings
No violations of significance were identified.
B. Licensee-Identified Violations
No violations of significance were identified.
2
REPORT DETAILS
OTHER ACTIVITIES
4OA5 Other Activities
Concerns With Single Failure Assumptions
a. Inspection Scope
During the 2005 NRC safety systems design and performance capability inspection, the inspectors noted that in Technical Specification (TS) Amendment No. 95 for Byron Station (changes to the ultimate heat sink to support steam generator replacement), the most limiting single failure evaluated was the failure of active breakers or switches in the 480 Vac service water cooling towers (SXCT) bus which resulted in the failure of one service water cooling tower fan. The inspectors noted that the licensee did not address the 480 Vac feed breakers between the 4160/480 Vac transformer and bus 131Z (for example). The inspectors also noted that a single failure of either of the breakers would de-energize the bus and result in a loss of two service water cooling tower fans. See below for an illustration of the configuration.
The licensee disagreed, stating the breakers were normally closed and therefore, a passive failure need not be considered.
The configuration of the breakers and the licensee's assessment that passive failures need not be considered was previously reviewed and approved by the NRC.
Specifically, in response to a request for additional information (RAI) dated July 30, 1997, the licensee stated that failure of the 4160 volt feed breakers was not postulated because the breakers did not automatically open on a loss-of-offsite power load sequence and therefore remained in the closed position for the accident. In the Safety Evaluation Report for the issued Amendment No. 95, dated December 12, 1997, the NRC "determined that the licensee's revised analysis is based on conservative assumptions including the most limiting single active failure as documented in the Current postulated breaker in single failure analysis. Originally, not postulated to fail. This was not challen ged durin g NRC review.Failure was not evaluated. However, failure would result in a loss of two fans. 4160 volt feed breaker 480 Vac feed breaker 3licensee's July 30, 1997, submittal in response to the staff's request for additional information. The licensee's proposed change to LCO 3.7.5.d is, therefore, acceptable." The issue was unresolved pending determination on whether the loss of the 4160 feed breaker should have been considered as the single failure.
Subsequent to the initiation of the URI, the inspectors held several discussions with the Electrical Branch in NRR and the Office of the General Counsel. The inspectors concluded that although Amendment No. 95 did not adequately distinguish single failure of electrical components (active vs passive), the failure of these feed breaker should have been considered in the licensee's analyses. As defined in 10 CFR Part 50, Appendix A: "A single failure means an occurrence which results in the loss of capability of a component to perform its intended safety functions. Multiple failures resulting from a single occurrence are considered to be a single failure. Fluid and electric systems are considered to be designed against an assumed single failure if neither (1) a single failure of any active component (assuming passive components function properly) nor (2) a single failure of a passive component (assuming active components function properly), results in a loss of the capability of the system to perform its safety functions." Consistent with the definition of a single failure presented in 10 CFR Part 50, Appendix A, and General Design Criterion 44, the spurious failure/opening of the 4160 volt or 480 Vac should have been considered a valid single failure and assessed. In reviewing the licensee's Amendment No. 95, the NRC did not evaluate the potential for a passive failure of the electrical breakers even though passive failures were required to be evaluated under 10 CFR Part 50, Appendix A. The current NRC staff position regarding the requirement to evaluate single passive failures of the electrical breakers is different than the position communicated in the Safety Evaluation Report for Amendment No. 95. Therefore, the provisions of 10 CFR 50.109 apply. That section defines backfitting as "the modification of or addition to systems, structures, components, or design of a facility, any of which may result from a new or amended provision in the Commission rules or the imposition of a regulatory staff position interpreting the Commission rules that is either new or different from a previously applicable staff position." After consultation with NRR and the Office of General Counsel, the inspectors determined that no backfit analysis is required under 10 CFR 50.109(a)(2) because the provisions of 10 CFR 50.109 (a)(4), were applicable, in that, a modification is necessary to bring a facility into compliance with the rules or orders of the Commission. The inspectors and members of the Electrical Branch in NRR discussed the conclusions and the need to be in compliance with the licensee. The licensee initiated corrective actions 00711704 and 663350. To compensate for the nonconforming condition, the licensee continued implementing an administrative control to allow only one fan out of service (OOS), compared to two allowed by TS. By allowing only one fan OOS, the licensee maintains the required five fans needed to mitigate their design basis accident (LOCA concurrent with LOOP in one unit and LOOP in the other unit), assuming the remaining two are lost due to the single failure of the breakers.
4In addition, the licensee plans to reanalyze their design basis which may require a TS change to increase the number of UHS fans required to be operable from six to seven. Consequently, the licensee invoked the provisions of NRC Administrative Letter (AL) 98-10, "Dispositioning of Technical Specifications That Are Insufficient to Assure Plant Safety" until such time the TS are revised or an engineering analysis demonstrates six fans are still acceptable for operability. This URI does not result in a violation because the NRC approved the original design basis analysis in the amendment request. Based on this review, this unresolved item is closed.
4OA6 Management Meeting(s)
.1 Exit Meeting Summary
- On March 28, 2008, the inspectors presented the inspection results to Mr. Hoots, and other members of the licensee staff. The licensee acknowledged the issues presented. The inspectors confirmed that none of the potential report input discussed was considered proprietary.
.2 Interim Exit Meetings
An interim meeting was conducted for:
- An exit meeting was presented to Mr. Blondin and his staff on Friday, December 14, 2007. ATTACHMENT:
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee
- D. Hoots, Site Vice President
- B. Grundmann, Regulatory Assurance Manager
- A. Daniels, NOS Manager
- J. Langan, Licensing Engineer
- T. Hulbert, NRC Coordinator Nuclear Regulatory Commission
- A.M. Stone, Chief, Engineering Branch 2
- B. Jones, Byron Resident Inspector (acting)
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Closed
- 05000454/2005002-06;
- 05000455/FIN-2005002-06 URI Concerns with Single Failure Assumptions
- 2
LIST OF DOCUMENTS REVIEWED
The following is a partial list of documents reviewed during the inspection.
- Inclusion on this list does not imply that the NRC inspector reviewed the documents in their entirety, but rather that selected sections or portions of the documents were evaluated as part of the overall inspection effort.
- Inclusion of a document on this list does not imply NRC acceptance of the document or any part of it, unless this is stated in the body of the inspection report. 4OA5 Other Activities
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- 00663350; Resolution of 2005 SSDI Unresolved Item on UHS; August 22, 2007 -
- 00711704; Resolution of NRC URI on UHS Design Basis; December 14, 2007 - ComEd Letter; Response to Request for Additional Information (RAI) - Ultimate Heat Sink Technical Specification Amendment; dated July 30, 1997 - NRC Letter; Issuance of Amendments; dated December 12, 1997
- USED [[]]
- AL Administrative Letter
- OOS Out of Service
- RAI Request for Additional Information
- SRP Standard Review Plan
- SXCT Service Water Cooling Tower
- TS Technical Specifications
- URI Unresolved Items