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| | number = ML14149A217 | | | number = ML14149A217 |
| | issue date = 05/21/2014 | | | issue date = 05/21/2014 |
| | title = Watts Bar Nuclear Plant, Unit 1 - E-mail Re. WBN 1 Hydrology LAR with UFSAR Changes (TAC MF9130) | | | title = E-mail Re. WBN 1 Hydrology LAR with UFSAR Changes |
| | author name = Lingam S P | | | author name = Lingam S |
| | author affiliation = NRC/NRR/DORL/LPWB | | | author affiliation = NRC/NRR/DORL/LPWB |
| | addressee name = Hess T A | | | addressee name = Hess T |
| | addressee affiliation = Tennessee Valley Authority | | | addressee affiliation = Tennessee Valley Authority |
| | docket = 05000391 | | | docket = 05000391 |
| | license number = NPF-090 | | | license number = NPF-090 |
| | contact person = Lingam S P | | | contact person = Lingam S |
| | case reference number = TAC ME9130 | | | case reference number = TAC ME9130 |
| | document type = E-Mail | | | document type = E-Mail |
| | page count = 2 | | | page count = 2 |
| | project = TAC:MF9130, TAC:ME9130 | | | project = TAC:ME9130, TAC:MF9130 |
| | stage = | | | stage = Other |
| }} | | }} |
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| =Text= | | =Text= |
| {{#Wiki_filter:From: Sent: To: Cc: Lingam, Siva Wednesday, May 21, 2014 2:23 PM Hess, Thomas A (tahess@tva.gov) Quichocho, Jessie; McMurtray, Anthony; Han, Andrew; Poole, Justin; Dian, Jeanne; Hoang, Dan; Cheng, Yuan Subject: Watts Bar, Unit 1 Hydrology LAR with UFSAR Changes (TAC No. ME9130) Per our telephone conversation yesterday, please note the following RAis that require your responses. At your request, Andy will arrange another conference call on May 27, 2014 for further discussion. Areas of concern to the LAR and proposed response to the RAI The LAR (ML 12236A 167) and the licensee's proposed response to the RAI (ML 14129A316) does not provide a sufficient dam safety factor for stability during a PMF. a-TVA failed to provide any analysis and calculations, or reference to industry standards (e.g. FERC, Army Corp of Engineers, and TVA River Operations), that support the UFSAR changes, that using a factor of safety greater than 1.0 for sliding, provides an adequate basis that dam structures are considered safe against failure. b-TVA did not describe or provide justification for the removal of factor of safety of 1.52 in the One-Half PMF on Watts Bar Dam. c-Under Section 2.4.1.2, "Hydrosphere' of the LAR, Enclosure 1, Attachment 1, TVA proposes to delete the following paragraph "in 1982, TVA officially began a safety review of all dams. The TVA Dam safety program was designed to be consistent with the Federal Emergency Management Agency's (FEMA) ... " Under Section 2.4.4, "Potential Dam Failures, Seismically Induced' of the LAR, Enclosure 1, Attachment 1, 41h paragraph, it notes that: "TVA Dam Safety Program (DSP), which is consistent with the Federal Guidelines for Dam Safety (37J * , conducts technical studies and engineering analyses to assess ... " (The superscript 37 represents the reference number used in the LAR, which refer to FEMA's dam safety guideline). However, the use of 1.0 as a factor of safety is contrary to the Federal Guidelines for Dam Safety indicate a factor of safety well above 1.0 (e.g., 1.25 or greater) against dam sliding. d-The UFSAR notes and TVA stated that the Watts Bar Licensing Basis is based on ANSI N170-1976 and RG 1.59. The ANSI N 170-1976 doesn't prescribe criteria to define the structural stability analysis. However, it indicates a higher level of conservatism should be applied as well as analysis to demonstrate acceptable safety for both sliding and overturning, in that: | | {{#Wiki_filter:From: Lingam, Siva Sent: Wednesday, May 21, 2014 2:23 PM To: Hess, Thomas A (tahess@tva.gov) |
| | Cc: Quichocho, Jessie; McMurtray, Anthony; Han, Andrew; Poole, Justin; Dian, Jeanne; Hoang, Dan; Cheng, Yuan |
| | |
| | ==Subject:== |
| | Watts Bar, Unit 1 Hydrology LAR with UFSAR Changes (TAC No. ME9130) |
| | Per our telephone conversation yesterday, please note the following RAis that require your responses. At your request, Andy will arrange another conference call on May 27, 2014 for further discussion. |
| | Areas of concern to the LAR and proposed response to the RAI The LAR (ML12236A167) and the licensee's proposed response to the RAI (ML14129A316) does not provide a sufficient dam safety factor for stability during a PMF. |
| | a- TVA failed to provide any analysis and calculations, or reference to industry standards (e.g. FERC, Army Corp of Engineers, and TVA River Operations), that support the UFSAR changes, that using a factor of safety greater than 1.0 for sliding, provides an adequate basis that dam structures are considered safe against failure. |
| | b- TVA did not describe or provide justification for the removal of factor of safety of 1.52 in the One-Half PMF on Watts Bar Dam. |
| | c- Under Section 2.4.1.2, "Hydrosphere' of the LAR, Enclosure 1, Attachment 1, TVA proposes to delete the following paragraph "in 1982, TVA officially began a safety review of all dams. The TVA Dam safety program was designed to be consistent with the Federal Emergency Management Agency's (FEMA) ... " Under Section 2.4.4, "Potential Dam Failures, Seismically Induced' of the LAR, Enclosure 1, Attachment 1, 41h paragraph, it notes that: "TVA Dam Safety Program (DSP), which is consistent with the Federal Guidelines for Dam Safety (3 7J * , conducts technical studies and engineering analyses to assess ... " (The superscript 37 represents the reference number used in the LAR, which refer to FEMA's dam safety guideline). However, the use of 1.0 as a factor of safety is contrary to the Federal Guidelines for Dam Safety indicate a factor of safety well above 1.0 (e.g., 1.25 or greater) against dam sliding. |
| | d- The UFSAR notes and TVA stated that the Watts Bar Licensing Basis is based on ANSI N170-1976 and RG 1.59. The ANSI N 170-1976 doesn't prescribe criteria to define the structural stability analysis. |
| | However, it indicates a higher level of conservatism should be applied as well as analysis to demonstrate acceptable safety for both sliding and overturning, in that: |
| * Section 5.5 ... "Analyses of dam failures are complex, many failures not being completely understood ... " | | * Section 5.5 ... "Analyses of dam failures are complex, many failures not being completely understood ... " |
| * Section 5.5.4 ... "Mode, degree, and likelihood of dam failure from floodwater surcharge cannot be predicted with usual engineering accuracy. Mode and degree of failure should be postulated using conservative judgment based to the extent possible on stability computations ... " Without a justification to the safety factors revised in the UFSAR, TVA's "No dam failure during the PMF event' assumption in the PMF analysis is not supported. 1 Siva P. Lingam U.S. Nuclear Regulatory Commission Project Manager (NRR/DORL/LP-WB) Watts Bar Nuclear Plant, Unit 1 Location: 08-05; Mail Stop: 08-B3 Telephone: 301-415-1564; Fax: 301-415-1222 E-mail address: siva.lingam@nrc.gov 2 | | * Section 5.5.4 ... "Mode, degree, and likelihood of dam failure from floodwater surcharge cannot be predicted with usual engineering accuracy. Mode and degree of failure should be postulated using conservative judgment based to the extent possible on stability computations ... " |
| }} | | Without a justification to the safety factors revised in the UFSAR, TVA's "No dam failure during the PMF event' assumption in the PMF analysis is not supported. |
| | 1 |
| | |
| | Siva P. Lingam U.S. Nuclear Regulatory Commission Project Manager (NRR/DORL/LP-WB) |
| | Watts Bar Nuclear Plant, Unit 1 Location: 08-05; Mail Stop: 08-B3 Telephone: 301-415-1564; Fax: 301-415-1222 E-mail address: siva.lingam@nrc.gov 2}} |
Letter Sequence Other |
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Initiation
- Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request
- Acceptance
- Supplement
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MONTHYEARML1104003842011-02-0707 February 2011 Enclosure 1, Hydrothermal Effects on the Ichthyoplankton from Watts Bar Nuclear Plant Supplemental Condenser Cooling Water Outfall in Upper Chickamauga Reservoir Project stage: Request ML1104003832011-02-0707 February 2011 Submittal of Hydrothermal Effects on Ichthyoplankton from Watts Bar Nuclear Plant Supplemental Condenser Cooling Water Outfall in Upper Chickamauge Reservoir, Report Project stage: Request ML11133A3642011-05-0606 May 2011 2010 Annual Non-Radiological Environmental Operating Report, Submitting This Report in Accordance with Section 5.4.1 of Appendix B, Environmental Protection Plan, of the WBN Operating License Project stage: Request ML11137A1222011-05-13013 May 2011 Annual Radiological Environmental Operating Report - 2010 Project stage: Request ML11143A0832011-05-19019 May 2011 Response to Request for Additional Information on Intake Pumping Station Water Velocity Project stage: Response to RAI ML11152A1602011-05-26026 May 2011 Response to Request for Information from Public Meeting on May 11, 2011 Project stage: Request ML11215A0992011-07-28028 July 2011 NPDES Permit No. TN0020168, TVA - Watts Bar Nuclear Plant, Spring City, Rhea County, Tennessee Project stage: Request ML11215A0982011-07-28028 July 2011 Notification of National Pollutant Discharge Elimination System Permit Renewal and Approval Project stage: Request ML11298A0942011-10-31031 October 2011 NUREG-0498 Supp 2 Dfc, (1.2) Cover - Pt 4, Draft Final Environmental Statement, Related to the Operation of Watts Bar Nuclear Plant, Unit 2 Project stage: Request ML11298A0952011-10-31031 October 2011 NUREG-0498 Supp 2 Dfc, (2.2) Pt 5 - End, Draft Final Environmental Statement, Related to the Operation of Watts Bar Nuclear Plant, Unit 2 Project stage: Request ML12171A0532012-06-13013 June 2012 Commitments Related to Updated Hydrologic Analysis Results Project stage: Request ML12236A1642012-07-19019 July 2012 Enclosure 1 Evaluation of Proposed Changes Tennessee Valley Authority Watts Bar Nuclear Plant, Unit 1 Project stage: Request ML12236A1652012-07-19019 July 2012 Application to Revise Watts Bar Nuclear Plant (WBN) Unit 1 Updated Final Safety Analysis Report Regarding Changes to Hydrologic Analysis (WBN-UFSAR-12-01) Project stage: Request ML12237A2712012-08-28028 August 2012 Acceptance of Requested Licensing Action Regarding Application to Revise Watts Bar Nuclear Plant Unit 1 Updated Final Safety Analysis Report Regarding Changes to Hydrologic Analysis Project stage: Acceptance Review ML13046A1122013-03-0101 March 2013 Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis Project stage: RAI ML13044A5612013-03-0101 March 2013 Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Re Flooding Hazard Reevaluation for Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident Project stage: RAI ML13067A3932013-03-0101 March 2013 Supplement to Application to Revise Watts Bar Nuclear Plant Unit 1 Updated Final Safety Analysis Report Regarding Changes to Hydrologic Analysis (WBN-UFSAR-12-01) Project stage: Request ML13080A0732013-03-12012 March 2013 Extension Request Regarding the Flooding Hazard Reevaluation Report Required by NRC Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendation.. Project stage: Request ML13126A2952013-04-30030 April 2013 Response to NRC Health Physics and Human Performance Branch Request for Additional Information Related to License Amendment Request for Watts Bar Nuclear Plant (WBN) Unit 1 Updated Final Safety Analysis Report Changes Associated with Hydrol Project stage: Request ML13127A1682013-05-14014 May 2013 Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis from Balance of Plant Branch Project stage: RAI ML13168A4102013-06-13013 June 2013 Response to NRC Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis Project stage: Response to RAI ML13276A2842013-08-15015 August 2013 E-mail - Request for RAI Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis Project stage: RAI ML13231A0822013-08-16016 August 2013 NRR E-mail Capture - Watts Bar, Unit 1 - RAI License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis Project stage: RAI CNL-13-112, Response to NRC Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis from Mechanical and Civil Engineering Branch2013-10-21021 October 2013 Response to NRC Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis from Mechanical and Civil Engineering Branch Project stage: Response to RAI CNL-13-147, Supplemental Response to NRC Health Physics & Human Performance Branch Request for Additional Information Related to License Amendment Request for Watts Bar Unit 1, Updated Final Safety Analysis Report Changes Associated with Hydrologic A2013-12-18018 December 2013 Supplemental Response to NRC Health Physics & Human Performance Branch Request for Additional Information Related to License Amendment Request for Watts Bar Unit 1, Updated Final Safety Analysis Report Changes Associated with Hydrologic Ana Project stage: Supplement CNL-14-004, Response to an NRC Verbal Request for Additional Information Related to the License Amendment Request to Updated Final Safety Analysis Report Changes Associated with the Hydrologic Analysis2014-01-17017 January 2014 Response to an NRC Verbal Request for Additional Information Related to the License Amendment Request to Updated Final Safety Analysis Report Changes Associated with the Hydrologic Analysis Project stage: Request ML14080A3352014-03-21021 March 2014 Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis Project stage: RAI ML14129A3162014-05-0909 May 2014 E-mail Re. RAI Related to LAR to Updated FSAR Changes Associated with Hydrologic Analysis from Mechanical and Civil Engineering Branch - Dam Stability Safety Factor Project stage: RAI ML14149A2172014-05-21021 May 2014 E-mail Re. WBN 1 Hydrology LAR with UFSAR Changes Project stage: Other ML14322B0182014-11-18018 November 2014 E-mail Re. Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis Project stage: RAI CNL-14-228, Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis2014-12-0505 December 2014 Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis Project stage: Request ML15005A3142015-01-28028 January 2015 Nuclear Plant, Unit 1 - Issuance of Amendment to Revise Updated Final Safety Analysis Report Regarding Changes to Hydrology Analysis Project stage: Approval 2013-03-01
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Category:E-Mail
MONTHYEARML24022A2592024-01-22022 January 2024 NRR E-mail Capture - Acceptance Review Results for Watts Bar Nuclear Plant, Unit 1, License Amendment Request to Revise TS LCO 3.8.2 to Remove Note C-S Diesel Generator ML24016A0762024-01-16016 January 2024 NRR E-mail Capture - Acceptance Review Results for Watts Bar Nuclear Plant, Units 1 and 2 - License Amendment Request to Rebaseline of Sections 3.1 and 3.2 of the Technical Specifications ML23347A0642023-12-13013 December 2023 12-13-23 Email from Kimberly Green to Wells, Russell, Subject: Results of NRC SUNSI Review of Watts Bar Nuclear Plant Dual-Unit UFSAR, Amendment 5 ML23334A0932023-11-28028 November 2023 NRR E-mail Capture - Acceptance Review Results for Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Revise TS Surveillance Requirement 3.9.5.1 to Reduce RHR Flow Rate During Mode 6 ML23319A1662023-11-0202 November 2023 NRR E-mail Capture - Acceptance Review Results for Browns Ferry Nuclear Plant, Sequoyah Nuclear Plant, and Watts Bar Nuclear Plant, Exemption Request Related to 10 CFR 37.11(c)(2) ML23254A2872023-09-11011 September 2023 NRR E-mail Capture - Acceptance Review Results for Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Revise TS Table 1.1-1 Re Number of Required Rvh Closure Bolts ML23236A2562023-08-24024 August 2023 NRR E-mail Capture - Acceptance Review Results for the Sequoyah and Watts Bar License Amendment Request to Adopt TSTF-567 (L-2023-LLA-0106) ML23191A8672023-07-10010 July 2023 NRR E-mail Capture - Acceptance Review Results for Watts Bar, Units 1 and 2, License Amendment Request to Adopt TSTF-501-A, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control ML23166A1142023-06-15015 June 2023 Document Request for Watts Bar Nuclear Plant - Radiation Protection Inspection - Inspection Report 2023-03 ML23150A2472023-05-25025 May 2023 NRR E-mail Capture - Audit Plan Related to Review of the Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Increase the Number of Tritium Producing Burnable Absorber Rods ML23116A1492023-04-21021 April 2023 NRR E-mail Capture - Acceptance Review Results for Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Increase the Number of Tritium Producing Burnable Absorber Rods ML23075A0032023-03-13013 March 2023 NRR E-mail Capture - Acceptance Review Results for Watts Bar, Units 1, 2, and 3, License Amendment Request to Revise TS 3.7.11, Required Actions A.1 and E.1 Footnotes Re Date for the Modification ML23072A0722023-03-10010 March 2023 NRR E-mail Capture - (External_Sender) State Consultation - Sequoyah Nuclear Plant, Units 1 and 2; and Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Revise Technical Specification 3.4.12 (L-2022-LLA-0103) ML23067A2372023-03-0808 March 2023 WB_2023-02_RP_inspection_doc_request ML23013A0382023-01-12012 January 2023 NRR E-mail Capture - (External_Sender) State Consultation for Alabama - Browns Ferry, Units 1, 2 and 3; Sequoyah, Units 1 and 2; and Watts Bar, Units 1 and 2, License Amendment Request to Adopt TSTF-529, Revision 4 (L-2022-LLA-0088) ML23013A0362023-01-12012 January 2023 NRR E-mail Capture - (External_Sender) State Consultation for Alabama - Browns Ferry, Units 1, 2 and 3; Sequoyah, Units 1 and 2; and Watts Bar, Units 1 and 2, License Amendment Request to Adopt TSTF-554-A, Revision 1 (L-2022-LLA-0100) ML22356A2982022-12-22022 December 2022 Email Response to Letter, Dated November 22, 2022 Regarding Watts Bar Integrated Inspection Report ML22353A0812022-12-15015 December 2022 NRR E-mail Capture - Acceptance Review Results for Watts Bar, Unit 2, Alternative Request WBN-2-ISI-01 Regarding Examination of Upper Head Injection Nozzle Dissimilar Metal Piping Butt Welds ML22348A0972022-12-14014 December 2022 NRR E-mail Capture - State Consultation - Browns Ferry, Units 1, 2 and 3; Sequoyah, Units 1 and 2; and Watts Bar, Units 1 and 2, License Amendment Request to Adopt TSTF-529, Revision 4 (L-2022-LLA-0088) ML22348A0442022-12-13013 December 2022 NRR E-mail Capture - State Consultation - Browns Ferry, Units 1, 2 and 3; Sequoyah, Units 1 and 2; and Watts Bar, Units 1 and 2, License Amendment Request to Adopt TSTF-554-A, Revision 1 (L-2022-LLA-0100) ML22343A0692022-12-0808 December 2022 NRR E-mail Capture - Request for Additional Information - Sequoyah Nuclear Plant, Units 1 and 2, and Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Revise Technical Specification 3.4.12 (L-2022-LLA-0103) ML22227A0712022-08-15015 August 2022 NRR E-mail Capture - Acceptance Review Results for Sequoyah and Watts Bar License Amendment Request to Revise TS 3.4.12 (EPID L-2022-LLA-0103) - Corrected ML22227A0262022-08-12012 August 2022 NRR E-mail Capture - Acceptance Review Results for Sequoyah and Watts Bar License Amendment Request to Revise TS 3.4.12 ML22227A0272022-08-11011 August 2022 NRR E-mail Capture - Request for Additional Information Related to Alternative Requests RP-11 for Sequoyah Nuclear Plant, Units 1 and 2, and IST-RR-9 for Watts Bar Nuclear Plant, Units 1 and 2 ML22215A2752022-08-0303 August 2022 NRR E-mail Capture - Acceptance Review Results for TVA Fleet License Amendment Request to Adopt TSTF-554 ML22194A8762022-07-13013 July 2022 NRR E-mail Capture - Acceptance Review Results for TVA Fleet License Amendment Request to Adopt TSTF-529 ML22166A4292022-06-0606 June 2022 NRR E-mail Capture - LAR to Adopt TSTF-577 ML22146A3342022-05-25025 May 2022 NRR E-mail Capture - Acceptance Review Results for Browns Ferry Nuclear Plant, Units 1, 2, and 3, Sequoyah Nuclear Plant, Units 1 and 2, and Watts Bar Nuclear Plant, Units 1 and 2, Relief Requests (EPID L-2022-LLR-0045 - 0047) ML22136A0182022-05-16016 May 2022 NRR E-mail Capture - Acceptance Review Results for Sequoyah Nuclear Plant, Units 1 and 2, Alternative Request RP-11 and Watts Bar Nuclear Plant, Units 1 and 2, Alternative Request IST-RR-9 ML22144A1002022-05-12012 May 2022 NRR E-mail Capture - Request for Additional Information Related to Tva'S Request to Revised the TVA Plants' Radiological Emergency Plans ML22123A1812022-05-0303 May 2022 NRR E-mail Capture - Acceptance Review Results for Sequoyah Nuclear Plant, Units 1 and 2, and Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Adopt TSTF-577 ML22115A1402022-04-25025 April 2022 NRR E-mail Capture - Requests for Confirmation of Information and Additional Information Regarding Watts Bar Nuclear Plant, Unit 2 Exemption Request Re 10 CFR Part 26 (L-2022-LLE-0017) ML22083A2372022-03-24024 March 2022 NRR E-mail Capture - Request for Additional Information and Confirmation of Information Related to Tva'S Request for Changes to Watts Bar Nuclear Plant, Units 1 and 2, Technical Specification 3.7.8 ML22081A2222022-03-22022 March 2022 NRR E-mail Capture - Acceptance Review Results for Watts Bar, Unit 1, License Amendment Request to Revise Allowable Value for TS Table 3.3.2-1, Function 6.e(1) ML22056A3802022-02-25025 February 2022 Document Request for Watts Bar Nuclear Plant - Radiation Protection Inspection - Inspection Report 2022-02 ML22131A1902022-02-23023 February 2022 NRR E-mail Capture - Acceptance Review Results for Watts Bar, Unit 2, Request to Revise the Reactor Vessel Surveillance Capsule Withdrawal Schedule ML22046A0392022-02-15015 February 2022 NRR E-mail Capture - Request for Confirmation of Information Regarding the Watts Bar Nuclear Plant, Unit 2, Cycle 4 Mid-Cycle Outage Generic Letter 95-05 Final Report ML22038A1882022-02-0404 February 2022 NRR E-mail Capture - Acceptance Review Results for TVA Fleet License Amendment Request to Revise the TVA Radiological Emergency Plan ML22018A0272022-01-18018 January 2022 2022 All RFI Responses - Exercise and Program Inspections - Revl ML22011A0382022-01-10010 January 2022 NRR E-mail Capture - Acceptance Review Results for Watts Bar, Units 1 and 2, License Amendment Request to Adopt TSTF-205-A, Rev. 3 and TSTF-563-A ML21306A2452021-11-0202 November 2021 NRR E-mail Capture - Acceptance Review Results for Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Revise Technical Specification 3.7.8, Essential Raw Cooling Water (ERCW) System ML21267A1392021-09-23023 September 2021 Document Request for Upcoming RP Inspection at Watts Bar ML21252A0912021-09-0909 September 2021 NRR E-mail Capture - Request for Comments on Proposed Issuance of Amendments to Watts Bar Nuclear Plant, Unit 2 - Revise Steam Generator Secondary Side Water Level ML21223A2592021-08-11011 August 2021 Affidavit - Prop Slides - Partially Closed Meeting with TVA Potential Watts Bar, Unit 2 Tube Locking LAR ML21221A2602021-08-0909 August 2021 NRR E-mail Capture - Request for Additional Information Regarding Tva'S Request to Revise Watts Bar, Unit 1 Tech Specs Related to Continuous Opening of the Auxiliary Building Secondary Containment Enclosure Boundary ML21215A1152021-07-26026 July 2021 NRR E-mail Capture - (External_Sender) Correction to WBN Chiller Replacement LAR ML21215A1142021-07-26026 July 2021 NRR E-mail Capture - (External_Sender) Correction to WBN Chiller Replacement LAR ML21197A0452021-07-15015 July 2021 WBN U1 Isi/Sgisi Request for Information (RFI) Letter ML21193A2422021-07-12012 July 2021 NRR E-mail Capture - Request for Additional Information Regarding Tva'S Request to Revise the Watts Bar Nuclear Plant, Unit 2 Technical Specifications Related to Steam Generator Inspection/Repair Program Provisions ML21189A0202021-06-29029 June 2021 NRR E-mail Capture - Acceptance Review Results for Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Revise Technical Specifications 3.3.6 and 3.3.7 Re Radiation Monitor Redundant Unit of Measure 2024-01-22
[Table view] |
Text
From: Lingam, Siva Sent: Wednesday, May 21, 2014 2:23 PM To: Hess, Thomas A (tahess@tva.gov)
Cc: Quichocho, Jessie; McMurtray, Anthony; Han, Andrew; Poole, Justin; Dian, Jeanne; Hoang, Dan; Cheng, Yuan
Subject:
Watts Bar, Unit 1 Hydrology LAR with UFSAR Changes (TAC No. ME9130)
Per our telephone conversation yesterday, please note the following RAis that require your responses. At your request, Andy will arrange another conference call on May 27, 2014 for further discussion.
Areas of concern to the LAR and proposed response to the RAI The LAR (ML12236A167) and the licensee's proposed response to the RAI (ML14129A316) does not provide a sufficient dam safety factor for stability during a PMF.
a- TVA failed to provide any analysis and calculations, or reference to industry standards (e.g. FERC, Army Corp of Engineers, and TVA River Operations), that support the UFSAR changes, that using a factor of safety greater than 1.0 for sliding, provides an adequate basis that dam structures are considered safe against failure.
b- TVA did not describe or provide justification for the removal of factor of safety of 1.52 in the One-Half PMF on Watts Bar Dam.
c- Under Section 2.4.1.2, "Hydrosphere' of the LAR, Enclosure 1, Attachment 1, TVA proposes to delete the following paragraph "in 1982, TVA officially began a safety review of all dams. The TVA Dam safety program was designed to be consistent with the Federal Emergency Management Agency's (FEMA) ... " Under Section 2.4.4, "Potential Dam Failures, Seismically Induced' of the LAR, Enclosure 1, Attachment 1, 41h paragraph, it notes that: "TVA Dam Safety Program (DSP), which is consistent with the Federal Guidelines for Dam Safety (3 7J * , conducts technical studies and engineering analyses to assess ... " (The superscript 37 represents the reference number used in the LAR, which refer to FEMA's dam safety guideline). However, the use of 1.0 as a factor of safety is contrary to the Federal Guidelines for Dam Safety indicate a factor of safety well above 1.0 (e.g., 1.25 or greater) against dam sliding.
d- The UFSAR notes and TVA stated that the Watts Bar Licensing Basis is based on ANSI N170-1976 and RG 1.59. The ANSI N 170-1976 doesn't prescribe criteria to define the structural stability analysis.
However, it indicates a higher level of conservatism should be applied as well as analysis to demonstrate acceptable safety for both sliding and overturning, in that:
- Section 5.5 ... "Analyses of dam failures are complex, many failures not being completely understood ... "
- Section 5.5.4 ... "Mode, degree, and likelihood of dam failure from floodwater surcharge cannot be predicted with usual engineering accuracy. Mode and degree of failure should be postulated using conservative judgment based to the extent possible on stability computations ... "
Without a justification to the safety factors revised in the UFSAR, TVA's "No dam failure during the PMF event' assumption in the PMF analysis is not supported.
1
Siva P. Lingam U.S. Nuclear Regulatory Commission Project Manager (NRR/DORL/LP-WB)
Watts Bar Nuclear Plant, Unit 1 Location: 08-05; Mail Stop: 08-B3 Telephone: 301-415-1564; Fax: 301-415-1222 E-mail address: siva.lingam@nrc.gov 2