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| | number = ML13269A287 | | | number = ML13269A287 |
| | issue date = 11/25/2013 | | | issue date = 11/25/2013 |
| | title = Dresden Nuclear Power Station, Units 2 and 3: LaSalle County Station, Units 1 and 2; and Quad Cities Nuclear Power Station, Units 1 and 2 - Request for Additional Information Related to Potential Loss of Spent Fuel Pool Cooling (TAC No. ME6 | | | title = County Station, Units 1 and 2; and Quad Cities Nuclear Power Station, Units 1 and 2 - Request for Additional Information Related to Potential Loss of Spent Fuel Pool Cooling |
| | author name = Hiland P L | | | author name = Hiland P |
| | author affiliation = NRC/NRR/DE | | | author affiliation = NRC/NRR/DE |
| | addressee name = Pacilio M J | | | addressee name = Pacilio M |
| | addressee affiliation = Exelon Nuclear | | | addressee affiliation = Exelon Nuclear |
| | docket = 05000237, 05000249, 05000254, 05000265, 05000373, 05000374 | | | docket = 05000237, 05000249, 05000254, 05000265, 05000373, 05000374 |
| | license number = | | | license number = |
| | contact person = Lamb J G | | | contact person = Lamb J |
| | case reference number = TAC ME6761 | | | case reference number = TAC ME6761 |
| | document type = Letter, Request for Additional Information (RAI) | | | document type = Letter, Request for Additional Information (RAI) |
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| =Text= | | =Text= |
| {{#Wiki_filter:UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555 November 25, 2013 | | {{#Wiki_filter:UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 November 25, 2013 Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555 |
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| ==SUBJECT:== | | ==SUBJECT:== |
| DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3; AND QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2-REQUEST FOR ADDITIONAL INFORMATION RELATED TO POTENTIAL LOSS OF SPENT FUEL POOL COOLING (TAC NO. ME6761) | | DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3; AND QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2- REQUEST FOR ADDITIONAL INFORMATION RELATED TO POTENTIAL LOSS OF SPENT FUEL POOL COOLING (TAC NO. ME6761) |
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| ==Dear Mr. Pacilio:== | | ==Dear Mr. Pacilio:== |
| The U.S. Nuclear Regulatory Commission (NRC) has received a petition submitted in accordance with Title 10 of the Code of Federal Regulations (1 0 CFR) 2.206, "Requests for Action under This Subpart," related to the potential loss of forced cooling to spent fuel pools (SFPs) at boiling-water reactors (BWRs). Mr. David Lochbaum, on behalf of the Union of Concerned Scientists (the Petitioner), requested that the NRC issue a demand for information (DFI) to all licensees of BWRs with Mark I or Mark II containment designs.1 The Petitioner requested that the DFI compel the licensees to describe how their individual facilities comply with 10 CFR Part 50, Appendix A, General Design Criterion (GDC) 44, "Cooling Water," and/or with 10 CFR 50.49, "Environmental Qualification of Electric Equipment Important to Safety for Nuclear Power Plants." The request was based on the need to transfer the heat from the SFP to an ultimate heat sink or account for the effects of potential boiling of the SFP following a design-basis event on the temperature, humidity, and submergence conditions within the reactor building.
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| The NRC staff initially considered this petition to be within the scope of issues that may be addressed as a result of the NRC's post-Fukushima actions because the request involved SFP boiling, which was an area of concern at the Fukushima Dai-ichi Nuclear Power Plant following the March 11, 2011, Great East Japan Earthquake and resultant tsunami. However, the focus of post-Fukushima actions has been on the protection of the fuel within the pool following beyond-design-basis events, rather than the potential for boiling in the SFPs to affect other systems and components essential for accident mitigation or safe shutdown following basis events. The NRC staff has completed an initial evaluation of the petition request using information contained in each subject facility's safety analysis report, and has concluded that additional information is necessary from certain facilities in order to evaluate the response of the facilities following design-basis events. Specifically, the NRC staff has selected facilities that share a common secondary containment surrounding two SFPs for its initial information request 1 See Letter from David Lochbaum, Director, Nuclear Safety Project, Union of Concerned Scientists, to R. William Borchardt, Executive Director for Operations, NRC (July 29, 2011) (Agencywide Documents Access and Management System (ADAMS) Accession No. ML 11213A030).
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| M. Pacilio because these facilities are more likely to have a high decay heat load due to refueling in one of the SFPs at a time when other equipment within the secondary containment may be essential for accident mitigation or safe shut down of an adjacent, operating unit. Some facilities in this group had sufficiently detailed information in the associated safety analysis report to indicate that forced SFP cooling could be reestablished to even an isolated SFP using high quality equipment designed to function following the facility design-basis earthquake.
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| However, other facility safety analysis reports had descriptions indicating that reestablishment of forced SFP cooling was not assured because, for example, connections from the residual heat removal (RHR) system to the SFP were not seismically qualified or the system was not configured to both draw water from and return cooled water to the SFP. The NRC staff believes, based on information in the safety analysis reports at Dresden Nuclear Power Station, Units 2 and 3 (Dresden), and Quad Cities Nuclear Power Station, Units 1 and 2 (Quad Cities), that a reliable means of SFP forced cooling may not exist at these facilities.
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| Since the RHR system may not be configured to provide reliable forced cooling to the SFP and the normal SFP cooling system was not safety-related at the Dresden, and Quad Cities facilities, the NRC staff believes that a sustained loss of forced cooling to the SFPs at these facilities could be a potential consequence of a design-basis earthquake with an associated loss of offsite power. The configuration of the secondary containment at these facilities may allow accumulation of evolved steam or condensed water in reactor building areas housing related equipment that could result in inoperability of this safety-related equipment.
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| In order to better understand the reliability of the SFP cooling systems, the expected response of the affected facilities to their loss, and the safety significance of the SFP cooling function at the Dresden and Quad Cities facilities, please respond to the request for additional information provided in the enclosure to this letter. Please provide the response within 90 days of the date of this letter. If you have any questions regarding this request, please contact the petition project manager, Mr. John Lamb, at 301-415-3100.
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| Docket Nos. 50-237 and 50-249 50-254 and 50-265
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| ==Enclosure:==
| | The U.S. Nuclear Regulatory Commission (NRC) has received a petition submitted in accordance with Title 10 of the Code of Federal Regulations (1 0 CFR) 2.206, "Requests for Action under This Subpart," related to the potential loss of forced cooling to spent fuel pools (SFPs) at boiling-water reactors (BWRs). Mr. David Lochbaum, on behalf of the Union of Concerned Scientists (the Petitioner), requested that the NRC issue a demand for information (DFI) to all licensees of BWRs with Mark I or Mark II containment designs. 1 The Petitioner requested that the DFI compel the licensees to describe how their individual facilities comply with 10 CFR Part 50, Appendix A, General Design Criterion (GDC) 44, "Cooling Water," and/or with 10 CFR 50.49, "Environmental Qualification of Electric Equipment Important to Safety for Nuclear Power Plants." The request was based on the need to transfer the heat from the SFP to an ultimate heat sink or account for the effects of potential boiling of the SFP following a design-basis event on the temperature, humidity, and submergence conditions within the reactor building. |
| | The NRC staff initially considered this petition to be within the scope of issues that may be addressed as a result of the NRC's post-Fukushima actions because the request involved SFP boiling, which was an area of concern at the Fukushima Dai-ichi Nuclear Power Plant following the March 11, 2011, Great East Japan Earthquake and resultant tsunami. However, the focus of post-Fukushima actions has been on the protection of the fuel within the pool following beyond-design-basis events, rather than the potential for boiling in the SFPs to affect other systems and components essential for accident mitigation or safe shutdown following design-basis events. |
| | The NRC staff has completed an initial evaluation of the petition request using information contained in each subject facility's safety analysis report, and has concluded that additional information is necessary from certain facilities in order to evaluate the response of the facilities following design-basis events. Specifically, the NRC staff has selected facilities that share a common secondary containment surrounding two SFPs for its initial information request 1 |
| | See Letter from David Lochbaum, Director, Nuclear Safety Project, Union of Concerned Scientists, to R. |
| | William Borchardt, Executive Director for Operations, NRC (July 29, 2011) (Agencywide Documents Access and Management System (ADAMS) Accession No. ML11213A030). |
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| Request for Additional Information cc w/encl: Distribution via ListServ Sincerely, Patrick L. Hiland, Director Division of Engineering Office of Nuclear Reactor Regulation REQUEST FOR ADDITIONAL INFORMATION RELIABILITY OF FORCED SPENT FUEL POOL COOLING 2.206 PETITION FROM UNION OF CONCERNED SCIENTISTS DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2 EXELON GENERATION COMPANY DOCKET NOS. 50-237, 50-249, 50-254 AND 50-265 Please respond to the following requests for information for each requested facility.
| | M. Pacilio because these facilities are more likely to have a high decay heat load due to refueling in one of the SFPs at a time when other equipment within the secondary containment may be essential for accident mitigation or safe shut down of an adjacent, operating unit. Some facilities in this group had sufficiently detailed information in the associated safety analysis report to indicate that forced SFP cooling could be reestablished to even an isolated SFP using high quality equipment designed to function following the facility design-basis earthquake. However, other facility safety analysis reports had descriptions indicating that reestablishment of forced SFP cooling was not assured because, for example, connections from the residual heat removal (RHR) system to the SFP were not seismically qualified or the system was not configured to both draw water from and return cooled water to the SFP. |
| The performance of structures, systems, and components (SSCs) should consider standard accident analysis methods and assumptions used in the safety analysis report, including loss of function under conditions beyond those considered in the design of the SSC and consideration of additional single failures.
| | The NRC staff believes, based on information in the safety analysis reports at Dresden Nuclear Power Station, Units 2 and 3 (Dresden), and Quad Cities Nuclear Power Station, Units 1 and 2 (Quad Cities), that a reliable means of SFP forced cooling may not exist at these facilities. |
| Operator actions may be included when the action is specified in existing operating, alarm response, or emergency procedure and the personnel expected to execute the action have been properly trained. 1. Describe the ability to maintain forced cooling of the spent fuel pool (SFP) using installed equipment following a design-basis earthquake with consequential loss of offsite power. Please consider SFP configurations encountered during routine refueling and normal operating conditions.
| | Since the RHR system may not be configured to provide reliable forced cooling to the SFP and the normal SFP cooling system was not safety-related at the Dresden, and Quad Cities facilities, the NRC staff believes that a sustained loss of forced cooling to the SFPs at these facilities could be a potential consequence of a design-basis earthquake with an associated loss of offsite power. The configuration of the secondary containment at these facilities may allow accumulation of evolved steam or condensed water in reactor building areas housing safety-related equipment that could result in inoperability of this safety-related equipment. |
| The normal SFP cooling system and the SFP cooling assist mode of the residual heat removal system should be considered at a minimum, and, if a sustained loss of forced SFP cooling is expected, identify the expected range of times for the pool to reach saturation conditions.
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| : 2. If the response to the above request determines that the SFP would experience a sustained loss of SFP forced cooling, describe the expected changes in environmental conditions within each affected secondary containment ventilation zone. Address the expected response of operators to manage environmental conditions, consistent with existing procedures, and describe the survivability of ventilation systems, such as the standby gas treatment system. Identify any secondary containment areas that could experience a harsh environment (i.e., an environment significantly more severe than the environment that would occur during normal plant operation with respect to radiation, temperature, humidity, or submergence of equipment as a result of accumulated condensate) as a result of the sustained loss of SFP forced cooling. 3. If the response to the above request identifies harsh environmental conditions in any area of the facility secondary containment, describe the effect of these environmental conditions on important-to-safety electrical equipment within those areas necessary to maintain the integrity of the reactor coolant pressure boundary, the capability to shut down the reactor and maintain it in a safe shutdown condition or the capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure.
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| Enclosure 4. If the response to the above request identifies that electrical equipment necessary to shut down the reactor and maintain safe shutdown conditions could be adversely affected by a sustained loss of SFP forced cooling potentially resulting from a basis event, describe any corrective actions that will be implemented at the affected facility and the basis for concluding that those actions would acceptably resolve the described condition.
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| M. Pacilio because, for example, connections from the residual heat removal (RHR) system to the SFP were not seismically qualified or the system was not configured to both draw water from and return cooled water to the SFP. The NRC staff believes, based on information in the safety analysis reports at Dresden Nuclear Power Station, Units 2 and 3 (Dresden), and Quad Cities Nuclear Power Station, Units 1 and 2 (Quad Cities}, that a reliable means of SFP forced cooling may not exist at these facilities.
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| Since the RHR system may not be configured to provide reliable forced cooling to the SFP and the normal SFP cooling system was not safety-related at the Dresden, and Quad Cities facilities, the NRC staff believes that a sustained loss of forced cooling to the SFPs at these facilities could be a potential consequence of a design-basis earthquake with an associated loss of offsite power. The configuration of the secondary containment at these facilities may allow accumulation of evolved steam or condensed water in reactor building areas housing related equipment that could result in inoperability of this safety-related equipment. | |
| In order to better understand the reliability of the SFP cooling systems, the expected response of the affected facilities to their loss, and the safety significance of the SFP cooling function at the Dresden and Quad Cities facilities, please respond to the request for additional information provided in the enclosure to this letter. Please provide the response within 90 days of the date of this letter. If you have any questions regarding this request, please contact the petition project manager, Mr. John Lamb, at 301-415-3100. | | In order to better understand the reliability of the SFP cooling systems, the expected response of the affected facilities to their loss, and the safety significance of the SFP cooling function at the Dresden and Quad Cities facilities, please respond to the request for additional information provided in the enclosure to this letter. Please provide the response within 90 days of the date of this letter. If you have any questions regarding this request, please contact the petition project manager, Mr. John Lamb, at 301-415-3100. |
| Sincerely, Ira/ Patrick L. Hiland, Director Division of Engineering Office of Nuclear Reactor Regulation Docket Nos. 50-237 and 50-249 50-254 and 50-265 | | Sincerely, Patrick L. Hiland, Director Division of Engineering Office of Nuclear Reactor Regulation Docket Nos. 50-237 and 50-249 50-254 and 50-265 |
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| ==Enclosure:== | | ==Enclosure:== |
| | Request for Additional Information cc w/encl: Distribution via ListServ |
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| | REQUEST FOR ADDITIONAL INFORMATION RELIABILITY OF FORCED SPENT FUEL POOL COOLING 2.206 PETITION FROM UNION OF CONCERNED SCIENTISTS DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2 EXELON GENERATION COMPANY DOCKET NOS. 50-237, 50-249, 50-254 AND 50-265 Please respond to the following requests for information for each requested facility. The performance of structures, systems, and components (SSCs) should consider standard accident analysis methods and assumptions used in the safety analysis report, including loss of function under conditions beyond those considered in the design of the SSC and consideration of additional single failures. Operator actions may be included when the action is specified in existing operating, alarm response, or emergency procedure and the personnel expected to execute the action have been properly trained. |
| | : 1. Describe the ability to maintain forced cooling of the spent fuel pool (SFP) using installed equipment following a design-basis earthquake with consequential loss of offsite power. |
| | Please consider SFP configurations encountered during routine refueling and normal operating conditions. The normal SFP cooling system and the SFP cooling assist mode of the residual heat removal system should be considered at a minimum, and, if a sustained loss of forced SFP cooling is expected, identify the expected range of times for the pool to reach saturation conditions. |
| | : 2. If the response to the above request determines that the SFP would experience a sustained loss of SFP forced cooling, describe the expected changes in environmental conditions within each affected secondary containment ventilation zone. Address the expected response of operators to manage environmental conditions, consistent with existing procedures, and describe the survivability of ventilation systems, such as the standby gas treatment system. Identify any secondary containment areas that could experience a harsh environment (i.e., an environment significantly more severe than the environment that would occur during normal plant operation with respect to radiation, temperature, humidity, or submergence of equipment as a result of accumulated condensate) as a result of the sustained loss of SFP forced cooling. |
| | : 3. If the response to the above request identifies harsh environmental conditions in any area of the facility secondary containment, describe the effect of these environmental conditions on important-to-safety electrical equipment within those areas necessary to maintain the integrity of the reactor coolant pressure boundary, the capability to shut down the reactor and maintain it in a safe shutdown condition or the capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure. |
| | Enclosure |
| | : 4. If the response to the above request identifies that electrical equipment necessary to shut down the reactor and maintain safe shutdown conditions could be adversely affected by a sustained loss of SFP forced cooling potentially resulting from a design-basis event, describe any corrective actions that will be implemented at the affected facility and the basis for concluding that those actions would acceptably resolve the described condition. |
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| Request for Additional Information cc w/encl: Distribution via ListServ Distribution:
| | ML13269A287 OFFICE DORULPLI-2/PM DORULPLII-2/LA DORULPLII-2/BC DSS/SBPB/BC DE/EEEB/BC NAME Jlamb A Baxter VRodriguez GCasto JZimmerman DATE 10/23/2013 10/22/2013 10/23/2013 10/30/2013 11/05/2013 OFFICE OGC- NLO DORUD DSS/D DE/D NAME JWachutka MEvans TMcGinty PHiland DATE 11/07/2013 11/21/2013 11/21/2013 11/25/2013}} |
| PUBLIC RidsNrrPMDresden RidsNrrDorl RidsNrrDe ADAMS Accession No ML13269A287 OFFICE DORULPLI-2/PM NAME Jlamb DATE 10/23/2013 OFFICE OGC-NLO NAME JWachutka DATE 11/07/2013 RidsNrrDeEeeb RidsNrrDss RidsNrrDoriLpll-2 RidsNrrPMQuadCities DORULPLII-2/LA DORULPLII-2/BC A Baxter VRodriguez 10/22/2013 10/23/2013 DORUD DSS/D MEvans TMcGinty 11/21/2013 11/21/2013 OFFICIAL RECORD COPY RidsNrrDssSbpb JLamb, NRRIDORL SJones, NRR DSS/SBPB/BC GCasto 10/30/2013 DE/D PHiland 11/25/2013 DE/EEEB/BC JZimmerman 11/05/2013}}
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Category:Letter
MONTHYEARIR 05000237/20240022024-08-14014 August 2024 Integrated Inspection Report 05000237/2024002 and 05000249/2024002 IR 05000373/20240022024-08-13013 August 2024 County Station - Integrated Inspection Report 05000373/2024002 and 05000374/2024002 ML24222A6772024-08-0909 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 05000237/20240102024-08-0909 August 2024 NRC Age-Related Degradation Inspection Report 05000237/2024010 and 05000249/2024010 ML24183A1082024-08-0808 August 2024 – Issuance of Amendment Nos. 302 and 298 Adoption of Tstf-505, Provide Risk Informed Extended Completion Times – RITSTF Initiative 4b SVP-24-049, Owners Activity Report Submittal Sixth 10-Year Interval 2024 Refueling Outage Activities2024-08-0707 August 2024 Owners Activity Report Submittal Sixth 10-Year Interval 2024 Refueling Outage Activities IR 05000237/20230112024-08-0707 August 2024 Reissue - Dresden Nuclear Power Station, Units 2 and 3 Comprehensive Engineering Team Inspection Report 05000237/2023011 and 05000249/2023011 IR 05000237/20200012024-08-0606 August 2024 Reissue - Dresden Nuclear Power Station, Units 2 and 3 - Integrated Inspection Report 05000237/2020001 and 05000249/2020001 IR 05000373/20244202024-08-0505 August 2024 County Station - Security Baseline Inspection Report 05000373 2024420 and 05000374 2024420 ML24184A1712024-08-0202 August 2024 SLRA Schedule Letter IR 05000254/20243012024-08-0101 August 2024 NRC Initial License Examination Report 05000254/2024301; 05000265/2024301 SVP-24-048, Registration of Use of Casks to Store Spent Fuel2024-07-31031 July 2024 Registration of Use of Casks to Store Spent Fuel RS-24-073, Alternative Schedule to Complete Decommissioning Beyond 60 Years of Permanent Cessation of Operations – Additional Information Supporting Request to Withhold Security-Related Information2024-07-31031 July 2024 Alternative Schedule to Complete Decommissioning Beyond 60 Years of Permanent Cessation of Operations – Additional Information Supporting Request to Withhold Security-Related Information ML24136A1322024-07-30030 July 2024 Transmittal Letter for Renewed License ML24208A0962024-07-25025 July 2024 57243-EN 57243 - Rssc Wire & Cable LLC, Dba Marmon - Part 21 Notification ML24193A0882024-07-24024 July 2024 Request for Withholding Information from Public Disclosure for Dresden Nuclear Power Station, Unit 1 Alternative Schedule to Complete Decommissioning Beyond 60-Years of Permanent Cessation of Operations (Docket 50-10) ML24204A1862024-07-24024 July 2024 – Regulatory Audit in Support of License Amendment Requests to Adopt TSTF 505, Revision 2; TSTF-591, Revision 0; and 10 CFR 50.69 RS-24-070, Independent Spent Fuel Storage Installation, Nine Mile Point, Units 1 and 2, Quad Cities, Units 1 and 2, R. E. Ginna - Nuclear Radiological Emergency Plan Document Revisions2024-07-12012 July 2024 Independent Spent Fuel Storage Installation, Nine Mile Point, Units 1 and 2, Quad Cities, Units 1 and 2, R. E. Ginna - Nuclear Radiological Emergency Plan Document Revisions SVP-24-041, Regulatory Commitment Change Summary Report2024-07-0505 July 2024 Regulatory Commitment Change Summary Report SVP-24-043, Registration of Use of Casks to Store Spent Fuel2024-07-0505 July 2024 Registration of Use of Casks to Store Spent Fuel ML24162A0982024-07-0303 July 2024 – Issuance of Amendment Nos. 301 and 297 Adoption of 10 CFR 50.69 “Risk Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors” RS-24-064, Nuclear Radiological Emergency Plan Document Revisions2024-06-28028 June 2024 Nuclear Radiological Emergency Plan Document Revisions ML24178A2522024-06-27027 June 2024 County Station – Acknowledgement of Response to NRC Inspection Report 05000373/2024001 and 05000374/2024001 and Disputed Non-Cited Violation IR 05000237/20243012024-06-27027 June 2024 NRC Initial License Examination Report 05000237/2024301; 05000249/2024301 ML24138A0572024-06-26026 June 2024 – Issuance of Amendment Nos. 285 and 278 Application to Adopt TSTF-564, “Safety Limit Mcpr” SVP-24-040, Registration of Use of Casks to Store Spent Fuel2024-06-25025 June 2024 Registration of Use of Casks to Store Spent Fuel ML24138A1812024-06-18018 June 2024 Aging Management Audit Plan Regarding the Subsequent License Renewal Application Review ML24128A2742024-06-14014 June 2024 Notice of Acceptance and Opportunity for Hearing - Letter RS-24-063, Response to Request for Additional Information for 10 CFR 50.55a Request No. I5R-222024-06-14014 June 2024 Response to Request for Additional Information for 10 CFR 50.55a Request No. I5R-22 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 SVP-24-039, Ile Post Exam Package Letter2024-06-12012 June 2024 Ile Post Exam Package Letter ML24156A2332024-06-11011 June 2024 Letter Supplemental Information for Alternative Schedule to Complete Decommissioning Beyond 60-Years of Permanent Cessation of Operations RS-24-053, Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed2024-06-0606 June 2024 Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed ML24151A6482024-06-0303 June 2024 Changes in Reactor Decommissioning Branch Project Management Assignments for Some Decommissioning Facilities SVPLTR 24-0020, Registration of Use of Casks to Store Spent Fuel2024-05-30030 May 2024 Registration of Use of Casks to Store Spent Fuel ML24183A2752024-05-30030 May 2024 Registration of Use of Casks to Store Spent Fuel IR 05000373/20240102024-05-29029 May 2024 County Station - Commercial Grade Dedication Inspection Report 05000373/2024010 and 05000374/2024010 ML24110A0492024-05-28028 May 2024 Audit Report Related to the TSTF-505 and 10 CFR 50.59 Amendments RS-24-056, Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors2024-05-28028 May 2024 Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors ML24079A0762024-05-23023 May 2024 Issuance of Amendments to Adopt TSTF 264 ML24145A0432024-05-23023 May 2024 Registration of Use of Casks to Store Spent Fuel 10 CFR 72.212 SVPLTR 24-0019, Registration of Use of Casks to Store Spent Fuel2024-05-23023 May 2024 Registration of Use of Casks to Store Spent Fuel ML24158A0012024-05-22022 May 2024 License Amendment Request to Adopt TSTF-564 (EPID L-2023-LLA-0120) Illinois State Concurrence ML24142A3352024-05-21021 May 2024 Quad Cities—Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes ML24141A2102024-05-20020 May 2024 Operator Licensing Examination Approval - Quad Cities Nuclear Power Station, May 2024 RS-24-055, 2023 Corporate Regulatory Commitment Change Summary Report2024-05-17017 May 2024 2023 Corporate Regulatory Commitment Change Summary Report IR 05000254/20240012024-05-14014 May 2024 Integrated Inspection Report Nos. 05000254/2024001 and 05000265/2024001 IR 05000373/20240012024-05-13013 May 2024 County Station - Integrated Report 05000373/2024001 and 05000374/2024001 RS-24-042, Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion2024-05-10010 May 2024 Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion SVP-24-034, Annual Radiological Environmental Operating Report2024-05-10010 May 2024 Annual Radiological Environmental Operating Report 2024-08-09
[Table view] Category:Request for Additional Information (RAI)
MONTHYEARML24197A0162024-07-12012 July 2024 NRR E-mail Capture - Final RAI - Constellation Energy Generation, LLC - Fleet Request - License Amendment Request to Adopt TSTF-591 ML24197A0482024-07-12012 July 2024 Information Request for the Quad Cities Nuclear Station Biennial Problem Identification and Resolution Inspection ML24142A3352024-05-21021 May 2024 Quad Cities—Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes ML24135A0182024-05-13013 May 2024 NRR E-mail Capture - Draft Request for Additional Information Quad Cities TSTF-505 Amendment ML24102A2422024-04-10010 April 2024 NRR E-mail Capture - Draft Request for Additional Information Quad Cities TSTF-505 and 50.69 Amendments ML24066A1532024-03-0606 March 2024 NRR E-mail Capture - Request for Additional Information TSTF-505, R2, Provide Risk-Informed Extended Completion Times, RITSTF (Risk-Informed Technical Specification Task Force) Initiative 4b and 10 CFR 50.69 License Amendments ML24066A0872024-03-0404 March 2024 NRR E-mail Capture - Dresden 2 and 3 - Request for Additional Information for Alternative Request I5R-22 ML24067A1242024-03-0101 March 2024 Email to Christian Williams: Request for Additional Information Regarding Dresden Relief Request Dated February 23, 2024 ML24053A1192024-02-22022 February 2024 Request for Information for the NRC Age-Related Degradation Inspection: Inspection Report 05000265/2024010 and 05000254/2024010 ML23360A6082023-12-27027 December 2023 County Station Request for Information for NRC Commercial Grade Dedication Inspection: Inspection Report 05000373/2024010 and 05000374/2024010 ML23349A0362023-12-14014 December 2023 NRR E-mail Capture - Draft Request for Additional Information Re Quad Cities Emergency Amendment Related to Unit 1 Diesel Generator Inoperability ML23338A1192023-11-21021 November 2023 NRR E-mail Capture - Draft Request for Additional Information Quad Cities Relief Request I5R-26 ML23264A7992023-09-21021 September 2023 NRR E-mail Capture - Final RAI - Constellation Energy Generation, LLC Fleet Request License Amendment Request to Adopt TSTF-580, Revision 1 ML23208A3182023-07-27027 July 2023 Notification of an NRC Biennial Licensed Operator Requalification Program Inspection and RFI ML23187A0462023-07-0606 July 2023 Notification of NRC Baseline Inspection and Request for Information; Inspection Report 05000237/2023004 ML23153A1562023-06-0202 June 2023 NRR E-mail Capture - RAI LaSalle pressure-temperature Limits Report (PTLR) Amendment Request ML23150A2482023-05-25025 May 2023 NRR E-mail Capture - RAI Re LaSalle Downcomer Analysis Amendment Request ML23118A1652023-04-28028 April 2023 NRR E-mail Capture - Request for Additional Information Quad Cities, Unit 2, Alternative Request I6R-11 ML23110A3202023-04-21021 April 2023 Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes Inspection ML23065A2832023-03-0707 March 2023 Request for Information for the NRC Quadrennial Comprehensive Engineering Team Inspection: Inspection Report 05000254/2023010 and 05000265/2023010 ML23052A0652023-02-21021 February 2023 NRR E-mail Capture - Dresden Units 2 and 3 - Request for Additional Information for Alternative Request RV-23H ML23037A9192023-02-0707 February 2023 Request for Information for the NRC Quadrennial Comprehensive Engineering Team Inspection: Inspection Report 05000237/2023011 and 05000249/2023011 ML23013A1502023-01-17017 January 2023 Notification of NRC Baseline Inspection and Request for Information; Inspection Report 05000254/2023002 ML23019A0132023-01-12012 January 2023 NRR E-mail Capture - Final RAI Dresden 2 and 3 - License Amendment Pertaining to GNF3 Fuel Transition ML22361A0792022-12-27027 December 2022 Notification of NRC Baseline Inspection and Request for Information (05000374/2023001) ML23004A0262022-12-16016 December 2022 NRR E-mail Capture - Draft Request for Additional Information - Quad Cities Alternative RV-04, Inservice Testing of High Pressure Coolant Injection Drain Pot Solenoid Valves (EPD L-2022-LLR-0070) ML22348A0452022-12-14014 December 2022 NRR E-mail Capture - Draft Request for Additional Information Regarding Quad Cities Alternative I6R-09 ML22290A0842022-10-13013 October 2022 NRR E-mail Capture - Dresden 2 and 3 - RAI License Amendment Request Regarding New Fuel Storage Vault and Spent Fuel Storage Pool Criticality Methodologies ML22227A1152022-09-27027 September 2022 Request for Withholding Information from Public Disclosure ML22270A1032022-09-27027 September 2022 Notification of NRC Baseline Inspection and Request for Information (05000249/2022004) ML22256A0112022-09-12012 September 2022 NRR E-mail Capture - Request for Additional Information LaSalle County Station, Units 1 and 2 and Quad Cities Nuclear Power Station, Units 1 and 2 License Amendments Related to Fuel Storage ML22249A2332022-09-0606 September 2022 Notification of NRC Fire Protection Team Inspection Request for Information Inspection Report 05000254/2022011 05000265/2022011 ML22203A0442022-07-21021 July 2022 Request for Additional Information (RAI) ML22206A0352022-07-13013 July 2022 NRR E-mail Capture - Draft RAI Quad Cities Alternative Related to Sblc Nozzle Inspection ML22199A2422022-07-13013 July 2022 NRR E-mail Capture - Draft RAI Dresden 2 and 3 Proposed Alternative Related to Sblc Nozzle Inspection for the Sixth Inservice Inspection Interval ML22193A0412022-07-11011 July 2022 NRR E-mail Capture - RAI Quad Cities License Amendment to Expand the Use of Prime Methods ML22182A1992022-07-0101 July 2022 NRR E-mail Capture - RAI Alternative RV-11, Code Case OMN-28 ML22178A1362022-06-28028 June 2022 Information Request to Support Upcoming Problem Identification and Resolution (Pi&R) Inspection at Quad Cities Station ML22164A7852022-06-13013 June 2022 NRR E-mail Capture - RAI Quad Cities Amendment for Spent Fuel Pool Storage Analysis ML22164A8562022-06-13013 June 2022 NRR E-mail Capture - RAI Quad Cities Alternative RV-08, Safety Relief Valves ML22164A8582022-06-13013 June 2022 NRR E-mail Capture - RAI Alternative RV-09, MSSVs ML22138A4112022-05-18018 May 2022 NRR E-mail Capture - Lasalle 1 and 2 - (RAI) License Amendment Request Regarding New Fuel Storage Vault and Spent Fuel Storage Pool Criticality Methodologies, with Changes to TS Sections 4.3.1 and 5.6.5 (EPID-L-2021-LLA-0124) ML22126A0392022-05-0606 May 2022 NRR E-mail Capture - Lasalle 1 and 2 Draft (RAI) License Amendment Request Regarding New Fuel Storage Vault and Spent Fuel Storage Pool Criticality Methodologies, with Proposed Changes to TS Sections 4.3.1 and 5.6.5 ML22097A0832022-04-0707 April 2022 County Station Information Request for the Cyber-Security Baseline Inspection, Notification to Perform Inspection 05000373/2022403 and 05000374/2022403 ML22076A1122022-03-15015 March 2022 Request for Additional Information Related to the Amendment Request to Transition to GNF3 Fuels (EPID L-2021-LLA-0159) (Redacted) ML22062B0232022-03-0303 March 2022 NRR E-mail Capture - EPID-L-2022-LLR-0028, LaSalle Unit 1, Request for Additional Information (Rai), LaSalle Unit 1, Relief Request I4R-13 Relief from Code Examinations for 1B33-F060A and 1B33-F060B Repairs ML22059A9902022-03-0101 March 2022 Supplemental Information Needed for Acceptance of Requested Licensing Action Amendment to Implement Prime Methodologies for Evaluating Thermal Overpower and Mechanical Overpower Limits for Non-Global Nuclear Fuels Fuel ML22041B5362022-02-10010 February 2022 NRR E-mail Capture - Constellation Energy Generation, LLC - Request for Additional Information Regarding Fleet License Amendment Request to Adopt TSTF-541 ML22039A1912022-02-0808 February 2022 Information Request for an NRC Triennial 10 CFR 50.59 (Evaluation of Changes, Tests, and Experiments) Baseline Inspection ML22020A0642022-01-13013 January 2022 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding Proposed Fleet Alternative for Repair of Water Level Instrumentation Partial Penetration Nozzles 2024-07-12
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 November 25, 2013 Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3; AND QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2- REQUEST FOR ADDITIONAL INFORMATION RELATED TO POTENTIAL LOSS OF SPENT FUEL POOL COOLING (TAC NO. ME6761)
Dear Mr. Pacilio:
The U.S. Nuclear Regulatory Commission (NRC) has received a petition submitted in accordance with Title 10 of the Code of Federal Regulations (1 0 CFR) 2.206, "Requests for Action under This Subpart," related to the potential loss of forced cooling to spent fuel pools (SFPs) at boiling-water reactors (BWRs). Mr. David Lochbaum, on behalf of the Union of Concerned Scientists (the Petitioner), requested that the NRC issue a demand for information (DFI) to all licensees of BWRs with Mark I or Mark II containment designs. 1 The Petitioner requested that the DFI compel the licensees to describe how their individual facilities comply with 10 CFR Part 50, Appendix A, General Design Criterion (GDC) 44, "Cooling Water," and/or with 10 CFR 50.49, "Environmental Qualification of Electric Equipment Important to Safety for Nuclear Power Plants." The request was based on the need to transfer the heat from the SFP to an ultimate heat sink or account for the effects of potential boiling of the SFP following a design-basis event on the temperature, humidity, and submergence conditions within the reactor building.
The NRC staff initially considered this petition to be within the scope of issues that may be addressed as a result of the NRC's post-Fukushima actions because the request involved SFP boiling, which was an area of concern at the Fukushima Dai-ichi Nuclear Power Plant following the March 11, 2011, Great East Japan Earthquake and resultant tsunami. However, the focus of post-Fukushima actions has been on the protection of the fuel within the pool following beyond-design-basis events, rather than the potential for boiling in the SFPs to affect other systems and components essential for accident mitigation or safe shutdown following design-basis events.
The NRC staff has completed an initial evaluation of the petition request using information contained in each subject facility's safety analysis report, and has concluded that additional information is necessary from certain facilities in order to evaluate the response of the facilities following design-basis events. Specifically, the NRC staff has selected facilities that share a common secondary containment surrounding two SFPs for its initial information request 1
See Letter from David Lochbaum, Director, Nuclear Safety Project, Union of Concerned Scientists, to R.
William Borchardt, Executive Director for Operations, NRC (July 29, 2011) (Agencywide Documents Access and Management System (ADAMS) Accession No. ML11213A030).
M. Pacilio because these facilities are more likely to have a high decay heat load due to refueling in one of the SFPs at a time when other equipment within the secondary containment may be essential for accident mitigation or safe shut down of an adjacent, operating unit. Some facilities in this group had sufficiently detailed information in the associated safety analysis report to indicate that forced SFP cooling could be reestablished to even an isolated SFP using high quality equipment designed to function following the facility design-basis earthquake. However, other facility safety analysis reports had descriptions indicating that reestablishment of forced SFP cooling was not assured because, for example, connections from the residual heat removal (RHR) system to the SFP were not seismically qualified or the system was not configured to both draw water from and return cooled water to the SFP.
The NRC staff believes, based on information in the safety analysis reports at Dresden Nuclear Power Station, Units 2 and 3 (Dresden), and Quad Cities Nuclear Power Station, Units 1 and 2 (Quad Cities), that a reliable means of SFP forced cooling may not exist at these facilities.
Since the RHR system may not be configured to provide reliable forced cooling to the SFP and the normal SFP cooling system was not safety-related at the Dresden, and Quad Cities facilities, the NRC staff believes that a sustained loss of forced cooling to the SFPs at these facilities could be a potential consequence of a design-basis earthquake with an associated loss of offsite power. The configuration of the secondary containment at these facilities may allow accumulation of evolved steam or condensed water in reactor building areas housing safety-related equipment that could result in inoperability of this safety-related equipment.
In order to better understand the reliability of the SFP cooling systems, the expected response of the affected facilities to their loss, and the safety significance of the SFP cooling function at the Dresden and Quad Cities facilities, please respond to the request for additional information provided in the enclosure to this letter. Please provide the response within 90 days of the date of this letter. If you have any questions regarding this request, please contact the petition project manager, Mr. John Lamb, at 301-415-3100.
Sincerely, Patrick L. Hiland, Director Division of Engineering Office of Nuclear Reactor Regulation Docket Nos. 50-237 and 50-249 50-254 and 50-265
Enclosure:
Request for Additional Information cc w/encl: Distribution via ListServ
REQUEST FOR ADDITIONAL INFORMATION RELIABILITY OF FORCED SPENT FUEL POOL COOLING 2.206 PETITION FROM UNION OF CONCERNED SCIENTISTS DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2 EXELON GENERATION COMPANY DOCKET NOS. 50-237, 50-249, 50-254 AND 50-265 Please respond to the following requests for information for each requested facility. The performance of structures, systems, and components (SSCs) should consider standard accident analysis methods and assumptions used in the safety analysis report, including loss of function under conditions beyond those considered in the design of the SSC and consideration of additional single failures. Operator actions may be included when the action is specified in existing operating, alarm response, or emergency procedure and the personnel expected to execute the action have been properly trained.
- 1. Describe the ability to maintain forced cooling of the spent fuel pool (SFP) using installed equipment following a design-basis earthquake with consequential loss of offsite power.
Please consider SFP configurations encountered during routine refueling and normal operating conditions. The normal SFP cooling system and the SFP cooling assist mode of the residual heat removal system should be considered at a minimum, and, if a sustained loss of forced SFP cooling is expected, identify the expected range of times for the pool to reach saturation conditions.
- 2. If the response to the above request determines that the SFP would experience a sustained loss of SFP forced cooling, describe the expected changes in environmental conditions within each affected secondary containment ventilation zone. Address the expected response of operators to manage environmental conditions, consistent with existing procedures, and describe the survivability of ventilation systems, such as the standby gas treatment system. Identify any secondary containment areas that could experience a harsh environment (i.e., an environment significantly more severe than the environment that would occur during normal plant operation with respect to radiation, temperature, humidity, or submergence of equipment as a result of accumulated condensate) as a result of the sustained loss of SFP forced cooling.
- 3. If the response to the above request identifies harsh environmental conditions in any area of the facility secondary containment, describe the effect of these environmental conditions on important-to-safety electrical equipment within those areas necessary to maintain the integrity of the reactor coolant pressure boundary, the capability to shut down the reactor and maintain it in a safe shutdown condition or the capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure.
Enclosure
- 4. If the response to the above request identifies that electrical equipment necessary to shut down the reactor and maintain safe shutdown conditions could be adversely affected by a sustained loss of SFP forced cooling potentially resulting from a design-basis event, describe any corrective actions that will be implemented at the affected facility and the basis for concluding that those actions would acceptably resolve the described condition.
ML13269A287 OFFICE DORULPLI-2/PM DORULPLII-2/LA DORULPLII-2/BC DSS/SBPB/BC DE/EEEB/BC NAME Jlamb A Baxter VRodriguez GCasto JZimmerman DATE 10/23/2013 10/22/2013 10/23/2013 10/30/2013 11/05/2013 OFFICE OGC- NLO DORUD DSS/D DE/D NAME JWachutka MEvans TMcGinty PHiland DATE 11/07/2013 11/21/2013 11/21/2013 11/25/2013