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MONTHYEARML0515201562005-06-0303 June 2005 Fort Calhoun, RAI, Potential Impact of Debris Blockage on Emergency Sump Recirculation at Pressurized-Water Reactors Project stage: RAI ML0517506252005-06-27027 June 2005 Forthcoming Meeting with Omaha Public Power District, Fort Calhoun Station, Unit 1 to Discuss Pilot Plant for the NRC Staff Resolution of Generic Letter 2004-02. Project stage: Meeting LIC-05-0090, Response to Request for Additional Information Related to Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors2005-08-0101 August 2005 Response to Request for Additional Information Related to Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors Project stage: Response to RAI ML0603804072006-02-0909 February 2006 RAI Re Response to Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design-Basis Accidents at Pressurized-Water Reactors. Project stage: RAI LIC-06-0070, Supplement to Revised Request for an Extension to the Completion Date for Corrective Actions Taken in Response to Generic Letter 2004-022006-06-28028 June 2006 Supplement to Revised Request for an Extension to the Completion Date for Corrective Actions Taken in Response to Generic Letter 2004-02 Project stage: Supplement LIC-08-0021, Supplemental Response to Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors2008-02-29029 February 2008 Supplemental Response to Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors Project stage: Request LIC-08-0098, Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors, Change of Commitment for Close-out Letter Submittal2008-09-0505 September 2008 Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors, Change of Commitment for Close-out Letter Submittal Project stage: Other ML0825906662008-09-12012 September 2008 E-mail from M. Lalor, GE to A. Wang, NRR/DORL/LPL4 Re Trip Report for Observation of GL-2004-2 Sump Testing Project stage: Other ML1001500722010-02-12012 February 2010 Request for Additional Information, Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors Project stage: RAI ML1004302742010-02-12012 February 2010 Notice of Forthcoming Teleconference with Omaha Public Power District to Discuss NRC Staff Request for Additional Information on Generic Letter 2004-02 for Fort Calhoun Station, Unit 1 Project stage: RAI ML1006200722010-03-23023 March 2010 Summary of Category 1, Teleconference with Omaha Public Power District to Discuss NRC Staff Request for Additional Information on Generic Letter 2004-02 for Fort Calhoun Station, Unit 1 Project stage: RAI ML1016205062010-06-14014 June 2010 Notice of Forthcoming Teleconference Meeting with Omaha Public Power District to Discuss NRC Staff Request for Additional Information Dated 2/12/2010 on Generic Letter 2004-02 for Fort Calhoun Station, Unit 1 Project stage: RAI ML1019403012010-07-29029 July 2010 6/30/2010 Summary of Teleconference Meeting with Omaha Public Power District to Discuss NRC Staff Request for Additional Information Dated 2/12/2010 on Generic Letter 2004-02 for Fort Calhoun Station, Unit 1 Project stage: RAI 2008-02-29
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Category:Letter
MONTHYEARML24019A1672024-01-31031 January 2024 Issuance of Amendment to Renewed Facility License to Add License Condition to Include License Termination Plan Requirements IR 05000285/20230062023-12-21021 December 2023 NRC Inspection Report 05000285/2023006 LIC-23-0007, Response to Fort Calhoun, Unit 1 & Independent Spent Fuel Storage Installation Review of License Amendment Request to Add License Condition to Include License Termination Plan Requirements Request for Additional Information2023-12-0606 December 2023 Response to Fort Calhoun, Unit 1 & Independent Spent Fuel Storage Installation Review of License Amendment Request to Add License Condition to Include License Termination Plan Requirements Request for Additional Information IR 05000285/20230052023-11-0202 November 2023 NRC Inspection Room 05000285/2023005 ML23276A0042023-09-28028 September 2023 U.S. EPA Response Letter to NRC Letter on Consultation and Finality on Decommissioning and Decontamination of Contaminated Sites MOU - Fort Calhoun Station, Unit 1 (License No. DPR-40, Docket No. 50-285) IR 05000285/20230042023-09-13013 September 2023 NRC Inspection Report 05000285/2023-004 LIC-23-0005, Response to Fort Calhoun Station, Unit No. 1 - Review of License Amendment Request to Add License Condition to Include License Termination Plan Requirements - 2nd Request for Additional Information (EPID L-2021-LIT-0000) June 2, 20232023-08-24024 August 2023 Response to Fort Calhoun Station, Unit No. 1 - Review of License Amendment Request to Add License Condition to Include License Termination Plan Requirements - 2nd Request for Additional Information (EPID L-2021-LIT-0000) June 2, 2023 ML23234A2412023-08-18018 August 2023 Email - Letter to M Porath Re Ft Calhoun Unit 1 LTP EA Section 7 Informal Consultation Request ML23234A2392023-08-18018 August 2023 Letter to B Harisis Re Ft Calhoun Unit 1 LTP EA State of Nebraska Comment Request.Pdf IR 05000285/20230032023-07-10010 July 2023 NRC Inspection Report 05000285/2023003 ML23082A2202023-06-26026 June 2023 Consultation on the Decommissioning of the Fort Calhoun Station Unit 1 Pressurized Water Reactor in Fort Calhoun, Nebraska ML23151A0032023-06-0505 June 2023 Review of License Amendment Request to Add License Condition to Include License Termination Plan Requirements 2nd Request for Additional Information (EPID L-2021-LIT-0000) June 2, 2023 IR 05000285/20230022023-06-0505 June 2023 NRC Inspection Report 05000285/2023002 LIC-23-0004, (FCS) Radiological Effluent Release Report and Radiological Environmental Operating Report2023-04-20020 April 2023 (FCS) Radiological Effluent Release Report and Radiological Environmental Operating Report LIC-23-0003, Annual Decommissioning Funding / Irradiated Fuel Management Status Report2023-03-15015 March 2023 Annual Decommissioning Funding / Irradiated Fuel Management Status Report LIC-23-0001, Response to Fort Calhoun Station, Unit No. 1 - Review of License Amendment Request to Add License Condition to Include License Termination Plan Requirements - Request for Additional Information2023-02-27027 February 2023 Response to Fort Calhoun Station, Unit No. 1 - Review of License Amendment Request to Add License Condition to Include License Termination Plan Requirements - Request for Additional Information IR 05000285/20230012023-02-24024 February 2023 NRC Inspection Report 05000285/2023001 ML22361A1022023-02-24024 February 2023 Reactor Decommissioning Branch Project Management Changes for Some Decommissioning Facilities and Establishment of Backup Project Manager for All Decommissioning Facilities LIC-23-0002, Independent Spent Fuel Storage Installation, Annual Radioactive Effluent Release Report2023-02-20020 February 2023 Independent Spent Fuel Storage Installation, Annual Radioactive Effluent Release Report ML23020A0462023-01-19019 January 2023 Threatened and Endangered Species List: Nebraska Ecological Services Field Office IR 05000285/20220062023-01-0505 January 2023 NRC Inspection Report 05000285/2022-006 ML22357A0662022-12-30030 December 2022 Technical RAI Submittal Letter on License Amendment Request for Approval of License Termination Plan IR 05000285/20220052022-10-26026 October 2022 NRC Inspection Report 05000285/2022-005 ML22276A1052022-09-30030 September 2022 Conclusion of Consultation Under Section 106 NHPA for Ft. Calhoun Station LTP ML22258A2732022-09-29029 September 2022 Letter to John Swigart, Shpo; Re., Conclusion of Consultation Under Section 106 Hnpa Fort Calhoun Station Unit 1 ML22265A0262022-09-26026 September 2022 U.S. Nuclear Regulatory Commission'S Analysis of Omaha Public Power District'S Decommissioning Status Report (License No. DPR-40, Docket No. 50-285) IR 05000285/20220042022-09-14014 September 2022 NRC Inspection Report 05000285/2022004 ML22138A1252022-08-0303 August 2022 Letter to Mr. Timothy Rhodd, Chairperson, Iowa Tribe of Kansas and Nebraska, Re., Ft Calhoun LTP Section 106 ML22138A1262022-08-0303 August 2022 Letter to Roger Trudell, Chairman, Santee Sioux Nation, Nebraska, Re., Ft Calhoun LTP Section 106 ML22101A1092022-08-0303 August 2022 Letter to Mr. Durell Cooper, Chairman, Apache Tribe of Oklahoma; Re., Ft Calhoun LTP Section 106 ML22138A1242022-08-0303 August 2022 Letter to Mr. Reggie Wassana, Governor, Cheyenne and Arapaho Tribes, Oklahoma, Re., Ft Calhoun LTP Section 106 ML22138A1292022-08-0303 August 2022 Letter to Tiauna Carnes, Chairperson, Sac and Fox Nation of Missouri in Kansas, Re., Ft Calhoun LTP Section 106 ML22138A1212022-08-0303 August 2022 Letter to Mr. Edgar Kent, Chairman, Iowa Tribe of Oklahoma, Re., Ft Calhoun LTP Section 106 ML22138A1282022-08-0303 August 2022 Letter to Victoria Kitcheyan, Chairwoman, Winnebago Tribe of Nebraska, Re., Ft Calhoun LTP Section 106 ML22138A1232022-08-0303 August 2022 Letter to Mr. Leander Merrick, Chairperson, Omaha Tribe of Nebraska, Re., Ft Calhoun LTP Section 106 ML22138A1222022-08-0303 August 2022 Letter to Mr. John Shotton, Chairman, Otoe-Missouria Tribe of Indians, Oklahoma, Re., Ft Calhoun LTP Section 106 ML22138A1272022-08-0303 August 2022 Letter to Vern Jefferson, Chairman, Sac and Fox Tribe of the Mississippi in Iowa, Re., Ft Calhoun LTP Section 106 ML22214A0922022-08-0303 August 2022 Letter to Stacy Laravie, Thpo, Ponca Tribe of Nebraska, Re., Ft Calhoun LTP Section 106 ML22138A1302022-08-0303 August 2022 Letter to Justin Wood, Principal Chief, Sac and Fox Nation, Oklahoma, Re., Ft Calhoun LTP Section 106 ML22159A2152022-06-28028 June 2022 Letter Forwarding FRN on Public Meeting and Request for Comment on License Termination Plan LIC-22-0010, Response to Fort Calhoun Station, Unit No. 1 - Review of License Termination Plan Requirements - Request for Additional Information2022-06-15015 June 2022 Response to Fort Calhoun Station, Unit No. 1 - Review of License Termination Plan Requirements - Request for Additional Information IR 05000285/20220032022-06-15015 June 2022 NRC Inspection Report 05000285/2022003 ML22119A2472022-05-0303 May 2022 Review of Amendment Request to Add a LC to Include LTP Requirements, RAI for Environmental Review IR 05000285/20220022022-04-28028 April 2022 NRC Inspection Report 050-00285/2022-002 LIC-22-0005, (FCS) Radiological Effluent Release Report and Radiological Environmental Operating Report2022-04-20020 April 2022 (FCS) Radiological Effluent Release Report and Radiological Environmental Operating Report LIC-22-0009, Annual Decommissioning Funding / Irradiated Fuel Management Status Report2022-03-30030 March 2022 Annual Decommissioning Funding / Irradiated Fuel Management Status Report 2024-01-31
[Table view] Category:Request for Additional Information (RAI)
MONTHYEARML23151A0042023-06-0606 June 2023 Second Set RAIs Rev 4 ML22357A0672022-12-30030 December 2022 Enclosure RAI Re Approval of License Termination Plan ML22119A2472022-05-0303 May 2022 Review of Amendment Request to Add a LC to Include LTP Requirements, RAI for Environmental Review ML20111A2162020-05-20020 May 2020 Revised PSDAR Request for Additional Information - RAI ML19241A1812019-08-21021 August 2019 Request for Additional Information on Proposed Changes to the FCS Emergency Plan and Emergency Action Level Scheme to Reflect an ISFSI-only Status ML18067A1432018-03-0808 March 2018 Enclosurequest for Additional Information (Letter to M. J. Fisher Request for Additional Information Regarding Omaha Public Power District'S Decommissioning Funding Plan Update for Fort Calhoun Station ISFSI) ML17236A3442017-08-24024 August 2017 NRR E-mail Capture - Final RAI for Fort Calhoun Exemption from 10 CFR 140.11(a)(4), Off-site Primary and Secondary Liability Insurance (MF9664) ML17236A3462017-08-24024 August 2017 NRR E-mail Capture - Final RAI for Fort Calhoun LAR Regarding Permanently Defueled TS (MF9567) ML17234A4692017-08-22022 August 2017 NRR E-mail Capture - Final RAI for Fort Calhoun LAR Regarding Removal of Dry Cask Loading Limits (MF9831) ML17194A9732017-07-13013 July 2017 NRR E-mail Capture - Final RAI for Fort Calhoun Ultimate Strength Design for Aux. Bldg LAR (MF8525) ML17112A0362017-04-20020 April 2017 NRR E-mail Capture - Fort Calhoun Station - Final RAI Regarding Permanently Defueled EP and EAL Scheme Change LAR ML17090A3942017-03-31031 March 2017 NRR E-mail Capture - Fort Calhoun - Final RAI Regarding Administrative Control TS Change LAR (MF8437) ML17082A0022017-03-22022 March 2017 NRR E-mail Capture - Fort Calhoun Station - Final Nsir/Dpr RAI Regarding Proposed Emergency Planning Exemption ML17081A0192017-03-21021 March 2017 NRR E-mail Capture - Fort Calhoun Station - Final RAI Regarding Proposed Emergency Planning Exemption ML17067A3862017-03-15015 March 2017 Request for Additional Information, Request for Approval of Certified Fuel Handler Training and Retraining Program to Facilitate Activities Associated with Decommissioning and Irradiated Fuel Handling Management ML17033A9692017-02-0202 February 2017 NRR E-mail Capture - Fort Calhoun Station - Final Request for Additional Information Concerning Post-Shutdown Eplan Amendment ML16263A0492016-09-20020 September 2016 Request for Additional Information, Request for Approval of Certified Fuel Handler Training and Retraining Program to Facilitate Activities Associated with Decommissioning and Irradiated Fuel Handling Management ML16174A1502016-06-27027 June 2016 Request for Additional Information, Relief Request, Use of Code Case N-513-4, Evaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or 3 Piping Section XI, Division 1 ML16146A1782016-05-27027 May 2016 Request for Additional Information, Round 2, Request to Revise Current Licensing Basis as Described in the Final Safety Analysis Report to Allow Equipment Classification Methodology from ANSI/ANS-58.14-2011 ML16106A0232016-04-29029 April 2016 Request for Additional Information, Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors ML16104A2872016-04-25025 April 2016 Request for Additional Information, License Amendment Request to Revise Current Licensing Basis to Use American Concrete Institute (Aci) Ultimate Strength Requirements ML16048A1542016-02-23023 February 2016 Request for Additional Information, License Amendment Request, Revise Current Licensing Basis as Described in the Final Safety Analysis Report to Allow Equipment Classification Methodology from ANSI/ANS-58.14-2011 ML16048A0242016-02-23023 February 2016 Request for Additional Information, License Amendment Request to Adopt Technical Specification Task Force (TSTF)-501, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control ML15343A1082015-12-15015 December 2015 Request for Additional Information, License Amendment Request to Make Administrative Changes to the Technical Specifications to Update Titles, Delete Obsolete Actions in Appendix B, and Relocate a Definition ML15323A0362015-11-24024 November 2015 Request for Additional Information, Relief Requests P-1 - LPSI and CS Pumps and P-2 - Adjusting Hydraulic Parameters Consistent W/Code Case OMN-21, Fifth 10-Year Inservice Testing Interval ML15194A2722015-07-14014 July 2015 Request for Additional Information, Adopt Emergency Action Level Scheme Pursuant to Nuclear Energy Institute (NEI) 99-01, Revision 6, Development of Emergency Action Levels for Non-Passive Reactors ML15057A0152015-03-0303 March 2015 Request for Additional Information, Materials Reliability Program (MRP)-227-A, Materials Reliability Program: Pressurized Water Reactor Internals Inspection and Evaluation Guidelines, Implementation Review ML15043A0612015-02-25025 February 2015 Request for Additional Information, Round 2, License Amendment Request to Revise Updated Safety Analysis Report to Allow Pipe Stress Analysis to Be Performed in Accordance with ASME Code Section III ML14353A0512014-12-22022 December 2014 Request for Additional Information, Request to Revise Updated Safety Analysis Report, Design and Evaluation of Seismic Class I Structures Using Ascm (Alternate Seismic Criteria and Methodologies) Developed Floor Response Spectra ML14259A3652014-09-24024 September 2014 Request for Additional Information, License Amendment Request to Revise Updated Safety Analysis Report to Allow Pipe Stress Analysis to Be Performed in Accordance with ASME Code Section III ML14195A0862014-07-16016 July 2014 Request for Additional Information Associated with Near-Term Task Force Recommendation 2.1, Seismic Hazard and Screening Report ML13317A5832013-11-25025 November 2013 Interim Staff Evaluation and Request for Additional Information Regarding Overall Integrated Plan for Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051) ML13304B4182013-11-0101 November 2013 Request for Additional Information Associated with Near-Term Task Force Recommendation 2.3, Seismic Walkdowns ML13282A5362013-10-0909 October 2013 Request for Additional Information Email, Round 2, Exemption Request, Use of Less Restrictive Work Hour Limitations During First 60 Days of Outage, in Lieu of 10 CFR 26.205(d)(7) ML13290A0022013-10-0909 October 2013 Request for Additional Information Email, License Amendment Request to Revise Current Licensing Basis of Pipe Break Criteria for High Energy Line Breaks ML13270A2872013-09-27027 September 2013 Email, Request for Additional Information Round 4 (Apla), Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light-Water Reactor Generating Plants (2001 Edition) ML13261A2122013-09-18018 September 2013 Request for Additional Information Email, Exemption Request, Use of Less Restrictive Work Hour Limitations During First 60 Days of Outage, in Lieu of 10 CFR 26.205(d)(7) ML13233A2482013-08-26026 August 2013 Supplemental Information Needed for Acceptance of Requested Licensing Action; Request for Exemption, Use of Less Restrictive Work Hour Limitations During First 60 Days of Outage in Lieu of 10 CFR 26.205(d)(7) ML13235A1682013-08-23023 August 2013 Draft Request for Additional Information Email, Overall Integrated Plan in Response to 3/12/2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order EA-12-051) ML13234A4352013-08-22022 August 2013 Request for Additional Information Email, Round 2, Request to Revise TS 2.0.1, General Requirements, and TS 2.7, Electrical Systems, for Inoperable System, Subsystem. or Component Due to Inoperable Power Source ML13226A1222013-08-14014 August 2013 Email, Request for Additional Information Round 3 (Apla), Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light-Water Reactor Generating Plants (2001 Edition) ML13212A0092013-07-30030 July 2013 Request for Additional Information Email, Request to Revise Technical Specification (TS) 2.0.1, General Requirements, and TS 2.7, Electrical Systems, for Inoperable System, Subsystem, or Component Due to Inoperable Power Source ML13205A1252013-07-24024 July 2013 Request for Additional Information Email Round 2, Exigent Amendment Request to Revise Current Licensing Basis to Adopt Revised Design Basis/Methodology for Addressing Design-Basis Tornado/Tornado Missile Impact ML13205A0182013-07-23023 July 2013 Request for Additional Information Email, Exigent License Amendment Request to Revise Current Licensing Basis to Adopt Revised Design Basis/Methodology for Addressing Design-Basis Tornado/Tornado Missile Impact ML13144A4822013-05-23023 May 2013 Request for Additional Information Email, Decommissioning Funding Status Report ML13100A1752013-04-10010 April 2013 Request for Additional Information Email, Request for One-Time Exemption from Requirements of 10 CFR 26.205(d)(7) to Allow Less Restrictive Working Hour Limitations to Support Activities for Plant Startup ML13086A4732013-03-27027 March 2013 Request for Additional Information Email, Request to Revise Technical Specification 2.16, River Level, and Establish EAL Classification Criteria for External Flooding Events Under Radiological Emergency Response Plan ML13120A0842013-03-22022 March 2013 Request for Additional Information Email Physical Security Plan, Training and Qualification Plan, and Safeguards Contingency Plan, Revision 20 (TAC No. D91660) ML13053A2262013-02-22022 February 2013 Email, Second Round Draft Request for Additional Information, Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light-Water Reactor Generating Plants. ML13016A4322013-01-16016 January 2013 E-mail, Request for Additional Information, Round 2, Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light-Water Reactor Generating Plants (2001 Edition) 2023-06-06
[Table view] |
Text
February 9, 2006 Mr. R. T. Ridenoure Vice President - Chief Nuclear Officer Omaha Public Power District Fort Calhoun Station FC-2-4 Adm.
Post Office Box 550 Fort Calhoun, Nebraska 68023-0550
SUBJECT:
FORT CALHOUN STATION, UNIT 1, REQUEST FOR ADDITIONAL INFORMATION RE: RESPONSE TO GENERIC LETTER 2004-02, POTENTIAL IMPACT OF DEBRIS BLOCKAGE ON EMERGENCY RECIRCULATION DURING DESIGN-BASIS ACCIDENTS AT PRESSURIZED-WATER REACTORS (TAC NO. MC4686)
Dear Mr. Ridenoure:
On September 13, 2004, the Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors, as part of the NRCs efforts to assess the likelihood that the emergency core cooling system (ECCS) and containment spray system (CSS) pumps at domestic pressurized water reactors (PWRs) would experience a debris-induced loss of net positive suction head margin during sump recirculation. The NRC issued this GL to all PWR licensees to request that addressees (1) perform a mechanistic evaluation using an NRC-approved methodology of the potential for the adverse effects of post-accident debris blockage and operation with debris-laden fluids to impede or prevent the recirculation functions of the ECCS and CSS following all postulated accidents for which the recirculation of these systems is required, and (2) implement any plant modifications that the above evaluation identifies as being necessary to ensure system functionality. Addressees were also required to submit information specified in GL 2004-02 to the NRC in accordance with Title 10 of the Code of Federal Regulations Section 50.54(f). Additionally, in the GL, the NRC established a schedule for the submittal of the written responses and the completion of any corrective actions identified while complying with the requests in the GL.
By letter dated March 4, 2005, as supplemented by letters dated August 1 and August 31, 2005, Omaha Public Power District provided a response to the GL. The NRC staff is reviewing and evaluating your response along with the responses from all PWR licensees. The NRC staff has determined that responses to the questions in the enclosure to this letter are necessary in order for the staff to complete its review. Please note that the Office of Nuclear Reactor Regulations Division of Component Integrity is still conducting its initial reviews with respect to coatings. Although some initial coatings questions are included in the enclosure to this letter, the NRC might issue an additional request for information regarding coatings issues in the near future.
R. T. Ridenoure Please provide your response within 60 days from the date of this letter. If you have any questions, please contact me at (301) 415-1445.
Sincerely,
/RA/
Alan B. Wang, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-285
Enclosure:
Request for Additional Information cc w/encl: see next page
R. T. Ridenoure Please provide your response within 60 days from the date of this letter. If you have any questions, please contact me at (301) 415-1445.
Sincerely,
/RA/
Alan B. Wang, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-285
Enclosure:
Request for Additional Information cc w/encl: see next page Distribution:
PUBLIC RidsNrrDorlDpr RArchitzel LPLIV Reading File WBateman THaffera RidsNrrDorlLpg RidsNrrPMJHopkins JLehning RidsNrrLALFeizollahi RidsNrrDorl HWagage RidsNrrPMAWang MMurphy SLu RidsOgcRp PKlein JHannon RidsAcrsAcnwMailCenter MYoder MScott RidsRgn4MailCenter (DGraves) BSingal, DORL DPR Accession No.: ML060380407
- per e-mail OFFICE LPL4/PM LPL4/LA DSS/SSIB DCI/CSGB LPL4/BC NAME AWang LFeizollahi DSolorio* EMurphy* DTerao DATE 02/07/06 02/07/06 2/6/06 02/08/06 02/09/06 OFFICIAL RECORD COPY
GL 2004-02 RAI Questions Plant Materials
- 1. (Not Applicable).
- 2. Identify the amounts (i.e., surface area) of the following materials that are:
(a) submerged in the containment pool following a loss-of-coolant accident (LOCA),
(b) in the containment spray zone following a LOCA:
- aluminum
- zinc (from galvanized steel and from inorganic zinc coatings)
- copper
- carbon steel not coated
- uncoated concrete Compare the amounts of these materials in the submerged and spray zones at your plant relative to the scaled amounts of these materials used in the Nuclear Regulatory Commission (NRC) nuclear industry jointly-sponsored Integrated Chemical Effects Tests (ICET) (e.g., 5x the amount of uncoated carbon steel assumed for the ICETs).
- 3. Identify the amount (surface area) and material (e.g., aluminum) for any scaffolding stored in containment. Indicate the amount, if any, that would be submerged in the containment pool following a LOCA. Clarify if scaffolding material was included in the response to Question 2.
- 4. Provide the type and amount of any metallic paints or non-stainless steel insulation jacketing (not included in the response to Question 2) that would be either submerged or subjected to containment spray.
Containment Pool Chemistry
- 5. Provide the expected containment pool pH during the emergency core cooling system (ECCS) recirculation mission time following a LOCA at the beginning of the fuel cycle and at the end of the fuel cycle. Identify any key assumptions.
- 6. For the ICET environment that is the most similar to your plant conditions, compare the expected containment pool conditions to the ICET conditions for the following items:
boron concentration, buffering agent concentration, and pH. Identify any other significant differences between the ICET environment and the expected plant-specific environment.
- 7. (Not Applicable).
Enclosure
Plant-Specific Chemical Effects
- 8. Discuss your overall strategy to evaluate potential chemical effects including demonstrating that, with chemical effects considered, there is sufficient net positive suction head (NPSH) margin available during the ECCS mission time. Provide an estimated date with milestones for the completion of all chemical effects evaluations.
- 9. Identify, if applicable, any plans to remove certain materials from the containment building and/or to make a change from the existing chemicals that buffer containment pool pH following a LOCA.
- 10. If bench-top testing is being used to inform plant-specific head loss testing, indicate how the bench-top test parameters (e.g., buffering agent concentrations, pH, materials, etc.)
compare to your plant conditions. Describe your plans for addressing uncertainties related to head loss from chemical effects including, but not limited to, use of chemical surrogates, scaling of sample size and test durations. Discuss how it will be determined that allowances made for chemical effects are conservative.
Plant Environment Specific
- 11. Provide a detailed description of any testing that has been or will be performed as part of a plant-specific chemical effects assessment. Identify the vendor, if applicable, that will be performing the testing. Identify the environment (e.g., borated water at pH 9, deionized water, tap water) and test temperature for any plant-specific head loss or transport tests. Discuss how any differences between these test environments and your plant containment pool conditions could affect the behavior of chemical surrogates.
Discuss the criteria that will be used to demonstrate that chemical surrogates produced for testing (e.g., head loss, flume) behave in a similar manner physically and chemically as in the ICET environment and plant containment pool environment.
- 12. For your plant-specific environment, provide the maximum projected head loss resulting from chemical effects (a) within the first day following a LOCA, and (b) during the entire ECCS recirculation mission time. If the response to this question will be based on testing that is either planned or in progress, provide an estimated date for providing this information to the NRC.
ICET 1 and ICET 5 Plants
- 13. (Not Applicable).
Trisodium Phosphate (TSP) Plants
- 14. Given the results from the ICET #3 tests (Agencywide Document Access and Management System (ADAMS) Accession No. ML053040533) and NRC-sponsored head loss tests (Information Notice 2005-26 and Supplement 1), estimate the concentration of dissolved calcium that would exist in your containment pool from all containment sources (e.g., concrete and materials such as calcium silicate, Marinite',
mineral wool, kaylo) following a large-break loss-of-coolant accident (LBLOCA) and discuss any ramifications related to the evaluation of chemical effects and downstream effects.
- 15. (Not Applicable).
- 16. (Not Applicable).
Additional Chemical Effects Questions
- 17. (Not Applicable).
- 18. (Not Applicable).
- 19. (Not Applicable).
- 20. (Not Applicable).
- 21. (Not Applicable).
- 22. (Not Applicable).
- 23. (Not Applicable).
- 24. (Not Applicable).
Coatings Generic - All Plants
- 25. Describe how your coatings assessment was used to identify degraded qualified/acceptable coatings and determine the amount of debris that will result from these coatings. This should include how the assessment technique(s) demonstrates that qualified/acceptable coatings remain in compliance with plant licensing requirements for design-basis accident (DBA) performance. If current examination techniques cannot demonstrate the coatings' ability to meet plant licensing requirements for DBA performance, licensees should describe an augmented testing and inspection program that provides assurance that the qualified/acceptable coatings continue to meet DBA performance requirements. Alternatively, assume all containment coatings fail and describe the potential for this debris to transport to the sump.
Plant Specific
- 26. (Not Applicable).
- 27. (Not Applicable).
- 28. (Not Applicable).
- 29. (Not Applicable).
- 30. The NRC staffs safety evaluation (SE) addresses two distinct scenarios for formation of a fiber bed on the sump screen surface. For a thin bed case, the SE states that all coatings debris should be treated as particulate and assumes 100% transport to the sump screen. For the case in which no thin bed is formed, the staffs SE states that the coatings debris should be sized based on plant-specific analyses for debris generated from within the ZOI and from outside the ZOI, or that a default chip size equivalent to the area of the sump screen openings should be used (Section 3.4.3.6). Describe how your coatings debris characteristics are modeled to account for your plant-specific fiber bed (i.e. thin bed or no thin bed). If your analysis considers both a thin bed and a non-thin bed case, discuss the coatings debris characteristics assumed for each case. If your analysis deviates from the coatings debris characteristics described in the staff-approved methodology, provide justification to support your assumptions.
- 31. You indicated that you would be evaluating downstream effects in accordance with WCAP 16406-P. The NRC is currently involved in discussions with the Westinghouse Owners Group (WOG) to address questions/concerns regarding this WCAP on a generic basis, and some of these discussions may resolve issues related to your particular station. The following issues have the potential for generic resolution; however, if a generic resolution cannot be obtained, plant-specific resolution will be required. As such, formal RAIs will not be issued on these topics at this time, but may be needed in the future. It is expected that your final evaluation response will specifically address those portions of the WCAP used, their applicability, and exceptions taken to the WCAP. For your information, topics under ongoing discussion include:
ee. Wear rates of pump-wetted materials and the effect of wear on component operation ff. Settling of debris in low flow areas downstream of the strainer or credit for filtering leading to a change in fluid composition gg. Volume of debris injected into the reactor vessel and core region hh. Debris types and properties ii. Contribution of in-vessel velocity profile to the formation of a debris bed or clog jj. Fluid and metal component temperature impact kk. Gravitational and temperature gradients ll. Debris and boron precipitation effects mm. ECCS injection paths nn. Core bypass design features oo. Radiation and chemical considerations pp. Debris adhesion to solid surfaces qq. Thermodynamic properties of coolant
- 32. Existing calculations have been performed to support crediting containment overpressure in NPSH margin calculations for a one-day period following a LOCA.
During the pilot audit review, the staff noted that containment overpressure was cited as a possible source of margin to provide relief against chemical effects, which might cause increasing head loss over a timeframe from days to weeks. The staff also noted
that, in the GL response, a potential license amendment to change the methodology for crediting overpressure was discussed. Will the revised methodology analyze extending overpressure credit beyond the one-day period currently analyzed, to the timeframe of days or weeks over which chemical effects head loss might act?
- 33. During the pilot audit review, the NRC staff noted a potential nonconservatism in that the refueling cavity drains were not explicitly modeled in the CFD analysis. The staff also observed, during the pilot audit review, that the potential exists that other significant sources of nonuniformity in the spray drainage pattern might exist. Will the CFD calculation be updated to account for refueling cavity drainage and/or any other potentially significant sources of concentrated containment spray or other water drainage into the containment pool?
- 34. During the pilot audit review, the staff noted that debris settling (i.e., the near-field effect) was credited to support the design basis of the proposed replacement strainers.
Please estimate the fraction of debris that settled and describe any analyses (beyond the limited generally qualitative information provided during the pilot audit) that were performed to correlate the scaled flow conditions and any surrogate debris in the test flume with the actual flow conditions and debris types in the plants containment pool.
- 35. Are there any vents or other penetrations through the strainer control surfaces which connect the volume internal to the strainer to the containment atmosphere above the containment minimum water level? In this case, dependent upon the containment pool height and strainer and sump geometries, the presence of the vent line or penetration could prevent a water seal over the entire strainer surface from ever forming; or else this seal could be lost once the head loss across the debris bed exceeds a certain criterion, such as the submergence depth of the vent line or penetration. According to Appendix A to Regulatory Guide 1.82, Revision 3, without a water seal across the entire strainer surface, the strainer should not be considered to be fully submerged.
Therefore, if applicable, explain what sump strainer failure criteria are being applied for the vented sump scenario described above.
- 36. The staff noted that the GL response stated that the licensee is evaluating a possible modification to the refueling cavity and reactor cavity drain caps to minimize potential debris blockage. Please confirm whether or not this modification will be performed. In addition, the staff requests that the licensee describe the potential types and characteristics of debris that could reach these drains. In particular, could large pieces of debris be blown into the upper containment by pipe breaks occurring in the lower containment, and subsequently drop into the cavity?
- 37. What is the minimum strainer submergence during the postulated LOCA? At the time that the re-circulation starts, most of the strainer surface is expected to be clean, and the strainer surface close to the pump suction line may experience higher fluid flow than the rest of the strainer. Has any analysis been done to evaluate the possibility of vortex formation close to the pump suction line and possible air ingestion into the ECCS pumps? In addition, has any analysis or test been performed to evaluate the possible
accumulation of buoyant debris on top of the strainer, which may cause the formation of an air flow path directly through the strainer surface and reduce the effectiveness of the strainer?
- 38. You submitted its computational fluid dynamics (CFD) calculation performed using a FLOW-3D computer code and the NRC staff reviewed it as part of a pilot plant audit.
However, the September 2005 GL response noted that OPPD used a different computer code, Fluent, for CFD analysis. Please identify major changes made to CFD modeling with the computer code change.
- 39. The September 2005 GL response noted that you are considering testing to determine calcium silicate debris transportability. If the testing is used to design the sump screen, please summarize the basis, results, and conclusions of the testing and how you apply testing for the design.
All other RAIs that were provided previously as part of the pilot audit process need to be answered for completeness.
Ft. Calhoun Station, Unit 1 cc:
Winston & Strawn Mr. Daniel K. McGhee ATTN: James R. Curtiss, Esq. Bureau of Radiological Health 1400 L Street, N.W. Iowa Department of Public Health Washington, DC 20005-3502 Lucas State Office Building, 5th Floor 321 East 12th Street Chairman Des Moines, IA 50319 Washington County Board of Supervisors P.O. Box 466 Blair, NE 68008 Mr. John Hanna, Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 310 Fort Calhoun, NE 68023 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-4005 Ms. Julia Schmitt, Manager Radiation Control Program Nebraska Health & Human Services R & L Public Health Assurance 301 Centennial Mall, South P.O. Box 95007 Lincoln, NE 68509-5007 Mr. David J. Bannister, Manager Fort Calhoun Station Omaha Public Power District Fort Calhoun Station FC-1-1 Plant P.O. Box 550 Fort Calhoun, NE 68023-0550 Mr. Joe L. McManis Manager - Nuclear Licensing Omaha Public Power District Fort Calhoun Station FC-2-4 Adm.
P.O. Box 550 Fort Calhoun, NE 68023-0550