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| | number = ML12158A508 | | | number = ML12158A508 |
| | issue date = 06/12/2012 | | | issue date = 06/12/2012 |
| | title = Watts Bar Nuclear Plant, Unit 1 - Safety Concern Regarding Hydrology/Flooding Subsequent to May 31, 2012, Public Meeting (TAC No. MD7169) | | | title = Safety Concern Regarding Hydrology/Flooding Subsequent to May 31, 2012, Public Meeting |
| | author name = Lyon C F, Milano P D | | | author name = Lyon C, Milano P |
| | author affiliation = NRC/NRR/DORL/LPWB | | | author affiliation = NRC/NRR/DORL/LPWB |
| | addressee name = Leeds E J | | | addressee name = Leeds E |
| | addressee affiliation = NRC/NRR | | | addressee affiliation = NRC/NRR |
| | docket = 05000390 | | | docket = 05000390 |
| | license number = | | | license number = |
| | contact person = Lyon F C | | | contact person = Lyon F |
| | case reference number = TAC MD7169 | | | case reference number = TAC MD7169 |
| | document type = Memoranda | | | document type = Memoranda |
| | page count = 3 | | | page count = 3 |
| | project = TAC:MD7169 | | | project = TAC:MD7169 |
| | stage = | | | stage = Meeting |
| }} | | }} |
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| =Text= | | =Text= |
| {{#Wiki_filter: June 12, 2012 MEMORANDUM TO: Eric J. Leeds, Director Office of Nuclear Reactor Regulation FROM: Carl F. Lyon, Project Manager /RA/ Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Patrick D. Milano, Senior Project Manager /RA/ Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation SUBJECT: WATTS BAR NUCLEAR PLANT, UNIT 1 - STATUS OF SAFETY CONCERN REGARDING HYDROLOGY/FLOODING SUBSEQUENT TO MAY 31, 2012, PUBLIC MEETING (TAC NO. MD7169) | | {{#Wiki_filter:June 12, 2012 MEMORANDUM TO: Eric J. Leeds, Director Office of Nuclear Reactor Regulation FROM: Carl F. Lyon, Project Manager /RA/ |
| This memorandum is to document our position, subsequent to the public meeting between senior management of the U.S. Nuclear Regulatory Commission (NRC) and the Tennessee Valley Authority (TVA) on May 31, 2012 (ADAMS Accession No. ML12157A457), that there is still no reasonable assurance of adequate safety at Watts Bar Nuclear Plant (WBN) Unit 1. In fact, the situation at WBN Unit 1 is worse because TVA's estimated probable maximum flood (PMF) level has been raised to 739.2 feet, which is an additional 0.2 feet beyond the initial 0.2 feet TVA estimated in the March 29, 2012, public meeting. At this new estimated level, some safety-related flood mitigation equipment will be flooded without compensatory measures. | | Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Patrick D. Milano, Senior Project Manager /RA/ |
| The thermal barrier booster pumps (TBBPs) will be flooded, and the margins to other flood mitigation equipment will be further reduced (spent fuel pool cooling pumps to less than 6 inches, and intake pumping station to less than 1 inch). Further, TVA is still evaluating the potential to compromise safety-related equipment in the intake pumping station and developing modifications to protect or mitigate the situation. TVA stated that they were reasonably certain that the additional 0.4 feet rise in PMF level was the final number and would not change, and that the calculation only lacks TVA's management review. The TBBPs are safety-related and required to function in a PMF event. TVA acknowledged that, based on the new PMF level, the TBBPs would be flooded. The temporary flood barriers to protect the TBBPs are staged, but not in place. Without them installed, the TBBPs will no longer perform their safety function in the flooding event. It is not reasonable to conclude that a staged flood barrier, which is necessary to protect flood mitigation equipment in the PMF event, is an adequate compensatory measure, nor does it regain compliance with the plant's licensing basis and the operating license. | | Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation |
| | |
| | ==SUBJECT:== |
| | WATTS BAR NUCLEAR PLANT, UNIT 1 - STATUS OF SAFETY CONCERN REGARDING HYDROLOGY/FLOODING SUBSEQUENT TO MAY 31, 2012, PUBLIC MEETING (TAC NO. MD7169) |
| | This memorandum is to document our position, subsequent to the public meeting between senior management of the U.S. Nuclear Regulatory Commission (NRC) and the Tennessee Valley Authority (TVA) on May 31, 2012 (ADAMS Accession No. ML12157A457), that there is still no reasonable assurance of adequate safety at Watts Bar Nuclear Plant (WBN) Unit 1. In fact, the situation at WBN Unit 1 is worse because TVAs estimated probable maximum flood (PMF) level has been raised to 739.2 feet, which is an additional 0.2 feet beyond the initial 0.2 feet TVA estimated in the March 29, 2012, public meeting. At this new estimated level, some safety-related flood mitigation equipment will be flooded without compensatory measures. |
| | The thermal barrier booster pumps (TBBPs) will be flooded, and the margins to other flood mitigation equipment will be further reduced (spent fuel pool cooling pumps to less than 6 inches, and intake pumping station to less than 1 inch). Further, TVA is still evaluating the potential to compromise safety-related equipment in the intake pumping station and developing modifications to protect or mitigate the situation. TVA stated that they were reasonably certain that the additional 0.4 feet rise in PMF level was the final number and would not change, and that the calculation only lacks TVAs management review. The TBBPs are safety-related and required to function in a PMF event. TVA acknowledged that, based on the new PMF level, the TBBPs would be flooded. The temporary flood barriers to protect the TBBPs are staged, but not in place. Without them installed, the TBBPs will no longer perform their safety function in the flooding event. It is not reasonable to conclude that a staged flood barrier, which is necessary to protect flood mitigation equipment in the PMF event, is an adequate compensatory measure, nor does it regain compliance with the plants licensing basis and the operating license. |
| TVA was unable to produce functionality assessments for the sand baskets at the four dams, but acknowledged that the sand baskets are depended upon for the PMF level calculations and flooding analysis. The sand baskets are not completely installed, and the NRC staff has questioned the capability of the sand baskets to perform their safety function in a flooding event. | | TVA was unable to produce functionality assessments for the sand baskets at the four dams, but acknowledged that the sand baskets are depended upon for the PMF level calculations and flooding analysis. The sand baskets are not completely installed, and the NRC staff has questioned the capability of the sand baskets to perform their safety function in a flooding event. |
| E. Leeds - 2 - Because the sand baskets comprise a necessary input assumption in PMF calculation, they are not "compensatory" in nature and must be ready to perform their intended function. Thus, it is not reasonable to conclude that the sand baskets are either adequate compensatory measures or reliable input assumptions. The regulations at 10 CFR 50.54(h) states that, "The licensee shall be subject to...all rules, regulations, and orders of the Commission." The operating license states that, "The facility will operate in conformity with...the rules and regulations of the Commission...." TVA continues to be in noncompliance with NRC's regulations related to flood protection, and; therefore, there is no reasonable assurance of adequate safety at WBN Unit 1. A confirmatory action letter will not restore TVA to compliance with the regulations. TVA remains outside of compliance until corrective actions (e.g., NRC-approved change to the licensing basis, permanent modifications) are complete. The NRC staff still has no analysis or safety basis to allow WBN Unit 1 to continue to operate with compensatory measures in place while the flooding issues are resolved, whether through a change to the licensing basis or by permanent modifications, either of which must be approved by the staff. NRC management needs to document its basis for the continued operation of the unit during the period that TVA attempts to regain compliance with its licensing basis. | | |
| Notwithstanding the above, TVA stated that their current operability determinations will be re-evaluated once the re-analysis is completed. In fact, RIS 2005-20, Revision 1, which addresses operability determinations and functionality assessments, discusses that an operability determination or functional assessment should be done on discovering that operability or functionality is called into question. TVA has been unable to produce current operability determinations for the resident inspector staff to review. For TVA to wait until the final PMF calculation review is concluded by its management does not demonstrate a good safety perspective. Regardless, operability does not equate to adequate safety, and there must always be adequate safety. | | E. Leeds Because the sand baskets comprise a necessary input assumption in PMF calculation, they are not compensatory in nature and must be ready to perform their intended function. Thus, it is not reasonable to conclude that the sand baskets are either adequate compensatory measures or reliable input assumptions. The regulations at 10 CFR 50.54(h) states that, The licensee shall be subject to...all rules, regulations, and orders of the Commission. The operating license states that, The facility will operate in conformity with...the rules and regulations of the Commission.... TVA continues to be in noncompliance with NRCs regulations related to flood protection, and; therefore, there is no reasonable assurance of adequate safety at WBN Unit 1. |
| At WBN Unit 1, the information currently available to the staff indicates that the potential flooding event is not bounded by the current licensing and design bases. Therefore, the staff's original 1995 determination of reasonable assurance of adequate safety is no longer supported. Without additional information, the staff has no reasonable assurance of safe operation of WBN Unit 1. The NRC staff has no analysis or safety basis to allow WBN Unit 1 to continue to operate with compensatory measures in place while the flooding issues are resolved. Docket No. 50-390 E. Leeds - 2 - Because the sand baskets comprise a necessary input assumption in PMF calculation, they are not "compensatory" in nature and must be ready to perform their intended function. Thus, it is not reasonable to conclude that the sand baskets are either adequate compensatory measures or reliable input assumptions. The regulations at 10 CFR 50.54(h) states that, "The licensee shall be subject to...all rules, regulations, and orders of the Commission." The operating license states that, "The facility will operate in conformity with...the rules and regulations of the Commission...." TVA continues to be in noncompliance with NRC's regulations related to flood protection, and; therefore, there is no reasonable assurance of adequate safety at WBN Unit 1. A confirmatory action letter will not restore TVA to compliance with the regulations. TVA remains outside of compliance until corrective actions (e.g., NRC-approved change to the licensing basis, permanent modifications) are complete. The NRC staff still has no analysis or safety basis to allow WBN Unit 1 to continue to operate with compensatory measures in place while the flooding issues are resolved, whether through a change to the licensing basis or by permanent modifications, either of which must be approved by the staff. NRC management needs to document its basis for the continued operation of the unit during the period that TVA attempts to regain compliance with its licensing basis. | | A confirmatory action letter will not restore TVA to compliance with the regulations. TVA remains outside of compliance until corrective actions (e.g., NRC-approved change to the licensing basis, permanent modifications) are complete. The NRC staff still has no analysis or safety basis to allow WBN Unit 1 to continue to operate with compensatory measures in place while the flooding issues are resolved, whether through a change to the licensing basis or by permanent modifications, either of which must be approved by the staff. NRC management needs to document its basis for the continued operation of the unit during the period that TVA attempts to regain compliance with its licensing basis. |
| Notwithstanding the above, TVA stated that their current operability determinations will be re-evaluated once the re-analysis is completed. In fact, RIS 2005-20, Revision 1, which addresses operability determinations and functionality assessments, discusses that an operability determination or functional assessment should be done on discovering that operability or functionality is called into question. TVA has been unable to produce current operability determinations for the resident inspector staff to review. For TVA to wait until the final PMF calculation review is concluded by its management does not demonstrate a good safety perspective. Regardless, operability does not equate to adequate safety, and there must always be adequate safety.
| | Notwithstanding the above, TVA stated that their current operability determinations will be re-evaluated once the re-analysis is completed. In fact, RIS 2005-20, Revision 1, which addresses operability determinations and functionality assessments, discusses that an operability determination or functional assessment should be done on discovering that operability or functionality is called into question. TVA has been unable to produce current operability determinations for the resident inspector staff to review. For TVA to wait until the final PMF calculation review is concluded by its management does not demonstrate a good safety perspective. Regardless, operability does not equate to adequate safety, and there must always be adequate safety. |
| At WBN Unit 1, the information currently available to the staff indicates that the potential flooding event is not bounded by the current licensing and design bases. Therefore, the staff's original 1995 determination of reasonable assurance of adequate safety is no longer supported. Without additional information, the staff has no reasonable assurance of safe operation of WBN Unit 1. The NRC staff has no analysis or safety basis to allow WBN Unit 1 to continue to operate with compensatory measures in place while the flooding issues are resolved. Docket No. 50-390 DISTRIBUTION: NON-PUBLIC LPWB R/F RidsNrrDorlLpwb Resource SShaeffer, RII RidsNrrDeEmcb Resource JSharkey, OCMKS JTappert, OCMWO RidsNrrLABClayton Resource RidsNrrPMWattsBar1 Resource PMilano, NRR RCroteau, RII JGwo, NRR BSosa, OCMGA RidsNrrDorlLpl2-2 RidsNrrDorl Resource RidsNrrOd Resource VMcCree, RII ACoggins, OCM PBubar, OCMWM GWilson, NRR THipschman, OCM ADAMS Accession No. ML12158A508 *previously concurred OFFICE DORL/LPWB/PM DORL/LPWB/SPM DORL/LPWB/LA DORL/LPWB/PM NAME FLyon PMilano BClayton* FLyon DATE 6/8/12 6/12/12 6/8/12 6/12/12 OFFICIAL RECORD COPY
| | At WBN Unit 1, the information currently available to the staff indicates that the potential flooding event is not bounded by the current licensing and design bases. Therefore, the staffs original 1995 determination of reasonable assurance of adequate safety is no longer supported. |
| }} | | Without additional information, the staff has no reasonable assurance of safe operation of WBN Unit 1. The NRC staff has no analysis or safety basis to allow WBN Unit 1 to continue to operate with compensatory measures in place while the flooding issues are resolved. |
| | Docket No. 50-390 |
| | |
| | ML12158A508 *previously concurred OFFICE DORL/LPWB/PM DORL/LPWB/SPM DORL/LPWB/LA DORL/LPWB/PM NAME FLyon PMilano BClayton* FLyon DATE 6/8/12 6/12/12 6/8/12 6/12/12}} |
Letter Sequence Meeting |
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MONTHYEARML1204812132012-02-17017 February 2012
10 CFR 50.54(f) Letter Courtesy Copies Re Thermal Conductivity Degradation
Project stage: Other
ML12115A1652012-04-24024 April 2012
Follow-Up to Safety Concern Regarding Hydrology/Flooding
Project stage: Other
ML12122A6742012-05-0303 May 2012
Open Door Policy in the Matter of Watts Bar Nuclear Plant, Unit 1-Safety Concern Regarding Hydrology/Flooding
Project stage: Other
ML12156A0762012-05-31031 May 2012
TVA Slides for Nrc/Tva Public Meeting on May 31, 2012
Project stage: Meeting
ML12158A5082012-06-12012 June 2012
Safety Concern Regarding Hydrology/Flooding Subsequent to May 31, 2012, Public Meeting
Project stage: Meeting
ML12173A3232012-06-21021 June 2012
Email Next Actions for Safety Concern at WBN1
Project stage: Other
2012-05-03
[Table View] |
|
|---|
Category:Memoranda
MONTHYEARML24089A0712024-04-0101 April 2024
3/20/24 & 3/27/24 2023 TVA Public Annual Assessment Meeting Summary
ML23142A2132023-05-22022 May 2023
Public Meeting Summary - 2022 Annual Assessment Meetings for Browns Ferry, Sequoyah and Watts Bar Nuclear Plants
ML21137A0022021-05-17017 May 2021
Public Meeting Summary - Browns Ferry, Sequoyah and Watts Bar Nuclear Plants, Docket Nos. 50-259, 50-260, 50-296, 50-327, 50-328, 50-390, and 50-391, Meeting Number 20210392
ML21060A9122021-03-17017 March 2021
Memo to File: Final Environmental Assessment and Finding of No Significant Impact for Initial and Updated Decommissioning Funding Plans for Watts Bar ISFSI
ML20127H8412020-05-0606 May 2020
Public Meeting Summary - Browns Ferry, Sequoyah and Watts Bar Nuclear Plant, Meeting No. 20200384
ML19142A3602019-05-21021 May 2019
May 9, 2019 Summary of Public Meeting; Watts Bar Nuclear Plant
ML18227A5992018-08-23023 August 2018
Request to Use a Later Edition of the Asme Boiler and Pressure Vessel Code, Section XI for Containment Inservice Inspection Activities
ML18165A3962018-06-14014 June 2018
Summary of Public Meeting Concerning Annual Assessment of Watts Bar Nuclear Plant - Docket Nos. 50-390 and 391
ML17356A2692017-12-20020 December 2017
Construction Lessons Learned Report
ML17332A2012017-11-28028 November 2017
Approval for Exceedance of the Watts Bar Maximum Baseline Inspection Samples
ML17192A0312017-06-26026 June 2017
Construction Inspection and Oversight Lessons Learned
ML17151A5092017-05-31031 May 2017
Public Meeting Summary - 2016 Annual Assessment Public Meeting Regarding Watts Bar Nuclear Plant
ML16252A2042016-09-0909 September 2016
Memo Ico Staff Review of Watts Bar Nuclear Plant Security Plan, Training and Qualification Plan, Safeguards Contingency Plan, Revision 20 (Ns113989) for Verification of ASM Order EA-14-044 Implementation (Cac# L25130)
ML16194A2522016-07-12012 July 2016
Memorandum to T. Mossman Technical Assistance Request-Review of Physical Security Plan for the Watts Bar Nuclear Plant Independent Spent Fuel Storage Installation (CAC No. L25130)
ML16131A6172016-05-10010 May 2016
Summary of Public Meeting with Watts Bar, Units 1 and 2, to Discuss the Annual Assessment
ML15259A4172015-10-21021 October 2015
the U.S. Nuclear Regulatory Commission Staff Evaluation of the Final Rule for Continued Storage of Spent Nuclear Fuel for the Operating License Environmental Review for Watts Bar Nuclear Plant, Unit 2
ML15288A3052015-10-15015 October 2015
Readiness of Watts Bar Unit 2 to Receive an Operating License
ML15096A2042015-04-23023 April 2015
Reactor Oversight Process Transition Plan for Watts Bar Nuclear Plant, Unit 2
ML15104A2982015-04-10010 April 2015
March 26, 2015, Summary of Public Meeting with Watts Bar, Unit 2, Senior Management
ML15104A2392015-04-10010 April 2015
March 26, 2015, Summary of Public Meeting with Watts Bar, Unit 2, EOC Assessment
ML15084A4242015-03-25025 March 2015
March 17, 2015, Summary of Public Meeting with Watts Bar, Unit 1, Concerning Annual Assessment
ML15015A4772015-02-0202 February 2015
Environmental Protection Plan (Non-Radiological) Technical Specification Review
ML14247A4522014-08-28028 August 2014
FEMA Response to NRC for Watts Bar Nuclear Site
ML14234A1462014-08-20020 August 2014
Memo to D. Safer Re M141030: Welcome Package for D.Safer for the Briefing on Watts Bar Unit 2 License Application Review
ML14231B0102014-08-19019 August 2014
Summary of the Public Meeting to Discuss Aspects of Tva'S Response to 2009 Confirmatory Order, August 18, 2014
ML14197A6082014-08-0606 August 2014
July 1, 2014, Summary of Category 1 Public Meeting with Tennessee Valley Authority to Discuss Seismic Hazard Reevaluations Associated with Implementation of Japan Lessons-Learned Near-Term Task Force Recommendation 2.1
ML14364A1682014-06-0202 June 2014
Flowserve Corp., Vermont, Formal Evaluation of Deviations Reported - Notification of Defect - Watts Bar II
ML14015A4522014-01-16016 January 2014
Notice of Meeting with Tennessee Valley Authority Regarding Open Items for Watts Bar Unit 2
ML14014A3262014-01-16016 January 2014
Notice of Forthcoming Meeting with Tennessee Valley Authority Regarding Watts Bar Nuclear Plant (WBN) Unit 1 Fire Protection Amendment Request
ML13352A4332013-12-19019 December 2013
Notice of Meeting with Tennessee Valley Authority Regarding Status of Construction and Licensing of Watts Bar Nuclear Plant, Unit 2
ML13213A4102013-08-0202 August 2013
Notice of Forthcoming Meeting with Tennessee Valley Authority on Watts Bar Electrical System LAR Review
ML13126A2522013-07-25025 July 2013
Request for Additional Information on the 2013 Decommissioning Funding Status Report
ML13149A1222013-05-30030 May 2013
Notice of Meeting with Tennessee Valley Authority Regarding Status of Construction and Licensing of Watts Bar Nuclear Plant, Unit 2
ML13105A3942013-04-16016 April 2013
Location Change - Notice of Forthcoming Meeting for Public Meeting with Tennessee Valley Authority (TVA) on 2.1 Response Extension Request, Sequoyah Nuclear Plant and Watts Bar Nuclear Plant
ML13078A4212013-03-19019 March 2013
Public Meeting Notice Tennessee Valley Authority, Browns Ferry, Sequoyah, Watts Bar for Commercial Grade Dedication Program
ML13072A1212013-03-19019 March 2013
Differing Professional Opinion Involving External Flooding (DPO-2012-003)
ML13035A0572013-02-0404 February 2013
2/7/13 Cancellation of Public Meeting with TVA Re 2.1 Response Schedule for Watts Bar Nuclear Plant, Unit 1
ML13025A1742013-01-25025 January 2013
Meeting Notice with TVA to Discuss the Schedule to Respond to Recommendation 2.1 of the Near-Term Task Force Review of the Insights from the Fukushima Da-ichi Accident
ML13007A0452013-01-0808 January 2013
1/23/13 Notice of Forthcoming Meeting with Tennessee Valley Authority Proposed Watts Bar Nuclear Plant, Units 1 License Amendment
ML12362A1132012-12-27027 December 2012
1/7/2013 Cancellation Notice of Public Meeting with TVA Re Watts Bar Nuclear Plant, Units 1 and 2, Regarding a Proposed License Amendment Request
ML12319A1722012-11-14014 November 2012
Meeting Notice with Tennessee Valley Authority to Discuss Hydrology Issues at Watts Bar Nuclear Plant, Unit 1
IR 05000390/20100082012-07-0606 July 2012
Errata for Electronic Closure of Watts Bar Inspection Report 05000390/2010-008 Memo Dated July 21, 2011 (ML 112020591)
ML12158A5082012-06-12012 June 2012
Safety Concern Regarding Hydrology/Flooding Subsequent to May 31, 2012, Public Meeting
ML12109A4282012-05-17017 May 2012
Final TIA 4 18 12
ML12122A6742012-05-0303 May 2012
Open Door Policy in the Matter of Watts Bar Nuclear Plant, Unit 1-Safety Concern Regarding Hydrology/Flooding
ML12115A1652012-04-24024 April 2012
Follow-Up to Safety Concern Regarding Hydrology/Flooding
ML1207501092012-03-15015 March 2012
Notice of Meeting with Tennessee Valley Authority to Discuss Pre-submittal Planning for Licensing Basis Change Regarding Hydrology for Watts Bar Nuclear Plant, Unit 1
ML1204610612012-02-0606 February 2012
Minutes of the ACRS Plant Operations and Fire Proctection Subcommittee Meeting December 15, 2011 (Open)
IR 05000327/20100082011-07-21021 July 2011
IR 05000327-10-008, 05000328-10-008 for Electronic Closure of Sequoyah, and IR 05000390-10-008 for Watts Bar
ML1120205912011-07-21021 July 2011
IR 05000327-10-008, 05000328-10-008 for Electronic Closure of Sequoyah, and IR 05000390-10-008 for Watts Bar
2024-04-01
[Table view] |
Text
June 12, 2012 MEMORANDUM TO: Eric J. Leeds, Director Office of Nuclear Reactor Regulation FROM: Carl F. Lyon, Project Manager /RA/
Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Patrick D. Milano, Senior Project Manager /RA/
Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
SUBJECT:
WATTS BAR NUCLEAR PLANT, UNIT 1 - STATUS OF SAFETY CONCERN REGARDING HYDROLOGY/FLOODING SUBSEQUENT TO MAY 31, 2012, PUBLIC MEETING (TAC NO. MD7169)
This memorandum is to document our position, subsequent to the public meeting between senior management of the U.S. Nuclear Regulatory Commission (NRC) and the Tennessee Valley Authority (TVA) on May 31, 2012 (ADAMS Accession No. ML12157A457), that there is still no reasonable assurance of adequate safety at Watts Bar Nuclear Plant (WBN) Unit 1. In fact, the situation at WBN Unit 1 is worse because TVAs estimated probable maximum flood (PMF) level has been raised to 739.2 feet, which is an additional 0.2 feet beyond the initial 0.2 feet TVA estimated in the March 29, 2012, public meeting. At this new estimated level, some safety-related flood mitigation equipment will be flooded without compensatory measures.
The thermal barrier booster pumps (TBBPs) will be flooded, and the margins to other flood mitigation equipment will be further reduced (spent fuel pool cooling pumps to less than 6 inches, and intake pumping station to less than 1 inch). Further, TVA is still evaluating the potential to compromise safety-related equipment in the intake pumping station and developing modifications to protect or mitigate the situation. TVA stated that they were reasonably certain that the additional 0.4 feet rise in PMF level was the final number and would not change, and that the calculation only lacks TVAs management review. The TBBPs are safety-related and required to function in a PMF event. TVA acknowledged that, based on the new PMF level, the TBBPs would be flooded. The temporary flood barriers to protect the TBBPs are staged, but not in place. Without them installed, the TBBPs will no longer perform their safety function in the flooding event. It is not reasonable to conclude that a staged flood barrier, which is necessary to protect flood mitigation equipment in the PMF event, is an adequate compensatory measure, nor does it regain compliance with the plants licensing basis and the operating license.
TVA was unable to produce functionality assessments for the sand baskets at the four dams, but acknowledged that the sand baskets are depended upon for the PMF level calculations and flooding analysis. The sand baskets are not completely installed, and the NRC staff has questioned the capability of the sand baskets to perform their safety function in a flooding event.
E. Leeds Because the sand baskets comprise a necessary input assumption in PMF calculation, they are not compensatory in nature and must be ready to perform their intended function. Thus, it is not reasonable to conclude that the sand baskets are either adequate compensatory measures or reliable input assumptions. The regulations at 10 CFR 50.54(h) states that, The licensee shall be subject to...all rules, regulations, and orders of the Commission. The operating license states that, The facility will operate in conformity with...the rules and regulations of the Commission.... TVA continues to be in noncompliance with NRCs regulations related to flood protection, and; therefore, there is no reasonable assurance of adequate safety at WBN Unit 1.
A confirmatory action letter will not restore TVA to compliance with the regulations. TVA remains outside of compliance until corrective actions (e.g., NRC-approved change to the licensing basis, permanent modifications) are complete. The NRC staff still has no analysis or safety basis to allow WBN Unit 1 to continue to operate with compensatory measures in place while the flooding issues are resolved, whether through a change to the licensing basis or by permanent modifications, either of which must be approved by the staff. NRC management needs to document its basis for the continued operation of the unit during the period that TVA attempts to regain compliance with its licensing basis.
Notwithstanding the above, TVA stated that their current operability determinations will be re-evaluated once the re-analysis is completed. In fact, RIS 2005-20, Revision 1, which addresses operability determinations and functionality assessments, discusses that an operability determination or functional assessment should be done on discovering that operability or functionality is called into question. TVA has been unable to produce current operability determinations for the resident inspector staff to review. For TVA to wait until the final PMF calculation review is concluded by its management does not demonstrate a good safety perspective. Regardless, operability does not equate to adequate safety, and there must always be adequate safety.
At WBN Unit 1, the information currently available to the staff indicates that the potential flooding event is not bounded by the current licensing and design bases. Therefore, the staffs original 1995 determination of reasonable assurance of adequate safety is no longer supported.
Without additional information, the staff has no reasonable assurance of safe operation of WBN Unit 1. The NRC staff has no analysis or safety basis to allow WBN Unit 1 to continue to operate with compensatory measures in place while the flooding issues are resolved.
Docket No. 50-390
ML12158A508 *previously concurred OFFICE DORL/LPWB/PM DORL/LPWB/SPM DORL/LPWB/LA DORL/LPWB/PM NAME FLyon PMilano BClayton* FLyon DATE 6/8/12 6/12/12 6/8/12 6/12/12
