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Category:Letter
MONTHYEARIR 05000338/20244202024-09-23023 September 2024 Security Baseline Inspection Report 05000338/2024420 and 05000339/2024420, Cover Letter IR 05000338/20244022024-09-17017 September 2024 Security Baseline Inspection Report 05000338/2024402 and 05000339/2024402 ML24215A2622024-08-28028 August 2024 Transmittal Letter for Subsequent Renewed License IR 05000338/20240052024-08-27027 August 2024 Updated Inspection Plan for North Anna Power Station, Units 1 and 2 (Report 05000338/2024005 and 05000339/2024005) 05000339/LER-2024-001, Loss of Generator Field for 2J Eog During 2-PT-82.282024-08-20020 August 2024 Loss of Generator Field for 2J Eog During 2-PT-82.28 ML24234A0742024-08-15015 August 2024 Notification of Deviation from Pressurized Water Reactor Owners Group (PWROG) Letter OG-23-63, NEI 03-08 Needed Guidance: PWR Thermal Shield Flexure Inspection Requirements ML24221A1902024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Pamunkey Indian Tribe ML24163A3002024-08-0808 August 2024 Request for Relief Request N1-I5-NDE-007 Inservice Inspection Alternative ML24206A0062024-08-0808 August 2024 Notice of Availability of the Final Environmental Impact Statement for the North Anna Nuclear Power Station Unit Numbers 1 and 2 Subsequent License Renewal (Docket Numbers: 50-338 and 50-339) ML24221A1832024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Chickahominy Indian Tribe-Eastern Division ML24221A1852024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Delaware Tribe of Indians ML24221A1942024-08-0808 August 2024 Tribal Section 106 Letters-North Anna-United Keetoowah Band of Cherokee Indians in Oklahoma ML24221A1912024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Rappahannock Tribe, Inc ML24221A1882024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Monacan Indian Nation ML24221A1932024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Upper Mattaponi Tribe ML24206A0052024-08-0808 August 2024 SLR Final EIS Letter to Achp ML24221A1842024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Delaware Nation, Oklahoma ML24221A1922024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Tuscarora Nation of New York ML24221A1872024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Eastern Shawnee Tribe of Oklahoma ML24221A1862024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Eastern Band of Cherokee Indians ML24221A1812024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Catawba Indian Nation ML24208A0142024-08-0808 August 2024 Tribal Section 106 Letters-North Anna-Absentee-Shawnee Tribe of Indians of Oklahoma ML24221A1822024-08-0808 August 2024 Tribal Section 106 Letters - North Anna - Chickahominy Indian Tribe ML24221A1892024-08-0808 August 2024 Tribal Section 106 Letters-North Anna - Nansemond Indian Nation ML24241A0692024-08-0606 August 2024 ISFSI, Submittal of Cask Registration for Spent Fuel Storage IR 05000338/20240022024-08-0202 August 2024 Integrated Inspection Report 05000338/2024002 and 05000339/2024002 ML24206A0432024-07-26026 July 2024 Feis - Letter to the Applicant 05000338/LER-2024-001, Automatic Reactor Trip Due to Prni High Negative Rate2024-07-25025 July 2024 Automatic Reactor Trip Due to Prni High Negative Rate ML24206A0902024-07-24024 July 2024 Owners Activity Report ML24178A2422024-06-25025 June 2024 2023 Annual Report of Emergency Core Cooling System (ECCS) Model, Changes Pursuant to the Requirements of 10 CFR 50.46 ML24177A2792024-06-20020 June 2024 Preparation and Scheduling of Operator Licensing Examinations ML24143A1622024-06-12012 June 2024 – Correction to Issuance of Amendment Nos. 297 and 280 and Surry Units 1 and 2, Correction to Issuance of Amendment Nos. 317 and 317, to Change Emergency Plan Staff Augmentation Times ML24170B0532024-06-10010 June 2024 DOM-NAF-2-P/NP-A, Revision 0.5, Reactor Core Thermal-Hydraulics Using the VIPRE-D Computer Code ML24165A1462024-06-0505 June 2024 Loss of Generator Field for 2J EDG During 2-PT-82.28 IR 05000338/20240102024-05-24024 May 2024 NRC Fire Protection Team Inspection (FPTI) Report 05000338/2024010 and 05000339/2024010 IR 05000338/20240012024-05-10010 May 2024 Integrated Inspection Report 05000338/2024001 and 05000339/2024001 IR 05000338/20244032024-04-30030 April 2024 – Security Baseline Inspection Report 05000338-2024403 and 05000339-2024403 ML24054A0142024-04-22022 April 2024 Issuance of Amendment Nos. 297 and 280, and Surry Power Station Unit Nos. 1 and 2, Issuance of Amendment Nos. 317 and 317, to Change Emergency Plan Staff Augmentation Times ML24110A1462024-04-18018 April 2024 Independent Spent Fuel Storage Installation (Sfsi) - Annual Radiological Environmental Operating Report ML24110A1502024-04-18018 April 2024 Independent Spent Fuel Storage Installation (ISFSI) - Annual Radioactive Effluent Release Report ML24110A1392024-04-18018 April 2024 Annual Environmental Operating Report ML24087A0572024-04-16016 April 2024 Correction to Issuance of Amendment Nos. 296 and 279 ML24088A2692024-03-27027 March 2024 Core Operating Limits Report Cycle 31 Pattern Sos Revision 0 ML24086A4292024-03-25025 March 2024 Response to Request for Additional Information Associated with Alternative Request N1-I5-NDE-007 Request to Deter Additional Required Reactor Coolant Pump Casing Inspection ML24082A2742024-03-22022 March 2024 Request for Approval of Alternative Request N1-I5-NDE-007 to Deter Additional Required Reactor Coolant Pump Casing Inspection ML24086A4682024-03-21021 March 2024 Summary of Facility Changes, Tests and Experiments ML24005A0042024-03-18018 March 2024 Issuance of Amendment Nos. 296 and 279, Regarding Revised Emergency Plan for Relocation of the Technical Support Center ML24074A3012024-03-14014 March 2024 Notification of Target Set Inspection and Request for Information (NRC Inspection Report 05000338-2024403 and 05000339-2024403) IR 05000338/20244012024-03-0808 March 2024 Security Baseline Inspection Report 05000338/2024401, 05000339/2024401 and 07200016/2024401 IR 05000338/20230062024-02-28028 February 2024 Annual Assessment Letter for North Anna Power Station, Units 1 and 2 - NRC Inspection Reports 05000338/2023006 and 05000339/2023006 2024-09-23
[Table view] Category:Licensee 30-Day Written Event Report
MONTHYEARML16134A0712016-05-0606 May 2016 Day Report of Emergency Core Cooling System (ECCS) Model Changes Pursuant to the Requirements of 10 CFR 50.46 ML13281A8032013-10-0202 October 2013 30-Day Report of Emergency Core Cooling System Model Changes Pursuant to the Requirements of 10 CFR 50.46 ML12334A3802012-11-14014 November 2012 Post Accident Monitoring Report ML11123A1912011-04-25025 April 2011 Independent Spent Fuel Storage Installation, Special Report on Nuhoms Dry Shielded Canisters Loaded to Incorrect Heat Load Limits ML1021401952010-07-29029 July 2010 Day Report of Emergency Core Cooling System Model Changes Pursuant to the Requirements of 10 CFR 50.46 ML0917402312009-06-17017 June 2009 Post Accident Monitoring (Pam) Report ML0708200742007-03-22022 March 2007 Day Report of Emergency Core Cooling System (ECCS) Model Changes Pursuant to the Requirements of 10 CFR 50.46 ML0526602322005-09-15015 September 2005 Post Accident Monitoring Instrumentation Report 2016-05-06
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VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 April 25, 2011 U. S. Nuclear Regulatory Commission Serial No.: 11-236 Attention:
Document Control Desk SPS: MPW RO Washington, D. C. 20555-0001 Docket No.: 72-56 VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA INDEPENDENT SPENT FUEL STORAGE INSTALLATION (ISFSI)SPECIAL REPORT ON NUHOMS DRY SHIELDED CANISTERS LOADED TO INCORRECT HEAT LOAD LIMITS This report is submitted in accordance with NUHOMS Certificate of Compliance 1030 Amendment 0 Technical Specifications 2.2.3 which requires a 30 day special report when any Functional and Operating Limit of Section 2.1 is violated.Fuel assemblies loaded into seven NUHOMS Dry Shielded Canisters (DSC) were above the decay heat limit for the loading zones in two of the center four zones and in effect had the Zone "la" and Zone "Ib" locations reversed.
As a result, the DSC Zone"l b" heat load limits were exceeded in some cases for these DSCs at the time of loading. The seven affected DSCs are: DOM-32PTH-004-C, 005-C, 007-C, 010-C, 013-C, 019-C, and GBC-32PTH-011-C.
The improper fuel assembly orientation was caused by a flawed evaluation of the interface between the DSC loading map and the station DSC loading procedure.
The evaluation did not ensure that the loading process would result in the correct orientation in the transfer cask and subsequently in the horizontal storage module. The orientation requirement was not included in engineering procedures governing DSC loading map preparation.
Upon discovery, an extent of condition review was performed on all North Anna DSCs and verified that all other heat load limits were met. Decay heat loads for all fuel assemblies loaded in the seven affected DSCs were reviewed.
All DSC loadings were determined to be below the DSC total heat load limit and the combined Zone 1 a and Zone 1 b total heat load limit when loaded. Decay heat loads for all affected assemblies were determined as of the date of discovery.
Eleven of the twelve affected assemblies now have decay heat loads that meet the decay heat limits for their location within the DSC. The remaining assembly currently has a decay heat load conservatively determined to be seven watts above its location limit and is expected to cool below the limit over the next four months.It was verified that the design basis shielding analysis bounded the as-loaded DSCs.The design basis shielding analysis assumes a DSC loading of 32 assemblies having source terms applicable to assemblies generating 1.5 kW of decay heat, which bounds the as-loaded DSCs. Reactivity parameters for the DSCs were verified to be unaffected by the loading error and remain bounded by the design basis analysis assumptions.
An evaluation conservatively bounding the as-loaded configurations of the affected DSCs has been performed.
This evaluation was performed consistent with the methods and assumptions used for the 32PTH DSC thermal analysis provided in the NUHOMS HD FSAR. The evaluation conservatively assumes decay heat loads consistent with the FSAR loading pattern configuration that achieves the maximum fuel clad temperature results, except for the Zone 1 b locations.
The Zone 1 b locations were increased to bound the as-loaded heat loads of the affected assemblies.
This analyzed configuration bounds the various heat load patterns for the affected DSCs. This also conservatively increases the total DSC decay heat to greater than the current design basis analysis decay heat, and results in a combined Zone Ia and lb total decay heat load greater than the allowable decay heat load for this region. Consistent with the NUHOMS HD FSAR, the evaluation assumes an ambient temperature of 11 5 0 F consistent with off-normal storage conditions for determining the maximum fuel cladding and component temperatures.
This evaluation concludes fuel cladding temperatures did not exceed the fuel cladding temperature design limit of 4000C (752 0 F) for storage or transfer conditions.
Further it shows that the DSC fuel compartment and support rail temperatures were bounded by those used in the design basis analysis, indicating there is no impact on the current design basis structural evaluation of the DSC basket due to the error. The evaluation also concludes that the maximum DSC internal pressures would have remained below the design limit for the as-loaded configurations.
Actions to prevent recurrence include: 1) reviewing NUHOMS Technical Specifications (TS) governing the loading process to ensure that any other areas requiring clarification are identified, addressed, and documented;
- 2) revising the procedure governing the loading map process to include all issues identified in the Technical Specification review, as well as other information identified as important to prevent recurrence; and 3)providing training on this issue to all personnel qualified to prepare DSC loading maps.These actions will be completed prior to loading additional DSCs.All seven DSCs are currently considered operable and performing their intended safety functions; all post-loading surveillance parameters are within acceptable limits. A TS exemption will be submitted, within ninety days from the date of this report, to allow continued storage of the affected fuel assemblies in their associated DSCs.The NRC Operations Center was notified of the event at 1114 hours0.0129 days <br />0.309 hours <br />0.00184 weeks <br />4.23877e-4 months <br /> on March 25, 2011 under Event Notification EN#46697.This report has been reviewed by the Facility Safety Review Committee and will be forwarded to the Management Safety Review Committee for its review.Sincerely, N. Larry Lane Site Vice President North Anna Power Station Commitments contained in this letter: TS Exemption submittal cc: U. S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 NRC Senior Resident Inspector North Anna Power Station