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Latest revision as of 08:41, 5 December 2019
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Category:Meeting Briefing Package/Handouts
MONTHYEARML22251A2352022-09-14014 September 2022 Presentation Slides for September 14, 2022, Observation Public Meeting ML22130A0092022-04-28028 April 2022 Duke Presentation for April 28, 2022 Public Meeting - Bolting Integrity ML22130A0102022-04-28028 April 2022 Duke Presentation for April 28, 2022 Public Meeting - Containment Liner ML22067A1992022-03-0303 March 2022 Annual Assessment Meeting Presentation ML22063A1142022-01-17017 January 2022 Duke Presentation for Public Meeting on February 17, 2022 ML21235A0452021-08-25025 August 2021 August 25, 2021, Oconee Nuclear Station, Units 1, 2, and 3 Subsequent License Renewal Application Public Environmental Scoping Meeting Presentation ML21102A0632021-04-14014 April 2021 ONS Slides for Pre-Application Meeting to Discuss Proposed Relief Request Related to Code Case N-853 ML21089A1732021-03-30030 March 2021 EOC Slides Final ML21081A1242021-03-22022 March 2021 EOC Slides Final ML20300A0902020-10-27027 October 2020 Subsequent License Renewal Environmental Pre-Application Meeting - NRC Presentation ML20300A0872020-10-27027 October 2020 Subsequent License Renewal Application NRC Environmental Pre-Application Meeting - Duke Energy Presentation ML19318F2912019-11-18018 November 2019 Duke Energy Presentation for the Pre-submittal Meeting on November 18, 2019, Regarding the RPV Stud Examination Relief Request ML19302E0512019-11-0606 November 2019 High Energy Line Break License Amendment Public Meeting ML19214A0562019-08-0707 August 2019 Presentation: Duke Energy Presubmittal Meeting - August 7, 2019 ML19207A0172019-07-30030 July 2019 Summary of Meeting with Duke Energy Carolinas, LLC to Discuss Proposed License Amendment Request for Oconee Nuclear Station, Units 1, 2, and 3 Regarding High Energy Line Break Licensing Basis ML18227B3212018-09-0505 September 2018 Tornado License Amendment Pre-Application Meeting Slides ML18134A2292018-05-14014 May 2018 Summary of April 26, 2018, Public Teleconference with Duke Energy Carolinas, LLC to Discuss Proposed License Amendment and 3 Regarding Technical Specification 3.8.1 ML17258A0122017-09-26026 September 2017 Presentation Slide Regarding Committee to Review Generic Requirements Meeting on Oconee Nuclear Station Cable Separation TIA ML15348A2032015-12-14014 December 2015 Duke Energy Presentation in Support of December 15, 2015, Public Meeting with NRC Staff Cable Testing Discussion for Proposed 50.55a Alternative Request ML15343A1142015-12-0808 December 2015 NRC Questions to Duke Energy Regarding Cable Testing in Support of Public Meeting on 12/15/15 ML15321A1782015-11-17017 November 2015 Presentation Material in Support of November 18, 2015 Pre-Application Meeting Between NRC and Duke 50.55a(z) Alternative to Code and Standards Requirements ML15286A0762015-10-13013 October 2015 Duke Energy Presentation in Support of October 13, 2015, Public Meeting with NRC Staff Pre-Application Meeting for LAR to Support Khu Stator Replacement. (Revised) ML15282A0722015-10-0909 October 2015 Duke Energy Presentation in Support of October 13, 2015, Public Meeting with NRC Staff Pre-Application Meeting for LAR to Support Khu Stator Replacement ML15148A2632015-05-27027 May 2015 Meeting Slides from the May 27, 2015 Oconee Major Projects Between Duke Energy and NRC ML15113A6262015-04-23023 April 2015 April 14, 2015 Summary of Public Meeting on Oconee Nuclear Station, Units 1, 2 and 3 to Discuss the Annual Assessment ML14356A0062014-12-0303 December 2014 Presentation at December 3, 2014, Category 1 Public Meeting with Duke Energy Carolinas, LLC to Discuss NTTF Recommendation 2.1, Flooding Response ML14211A2132014-07-31031 July 2014 Duke Energy Presentation for 2014-07-31 Meeting ML14211A2162014-07-31031 July 2014 NRC Meeting Slides 7-31-14 Reg Conference ML14147A3652014-05-27027 May 2014 Annual Assessment Public Meeting Summary Memo ML14058A0772014-02-0404 February 2014 Slides on Oconee Ssf Flood Barrier Breach SDP Lessons Learned ML14058A0742014-02-0404 February 2014 Slides on Oconee Ssf Flood Barrier Breach SDP - Lessons Learned ML14058A0482014-02-0404 February 2014 NRR Briefing on Oconee Flood Protection (Nrr/Dra) ML13336A5452013-11-13013 November 2013 Presentation Slides from Meeting with Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3, Keowee Hydro Unit Generator Field Pole Rewind Project - License Amendment Request ML13312A9882013-11-0808 November 2013 Summary of Public Meeting with Duke Energy Carolinas, LLC, to Provide Opportunities to Discuss the Planned Fukushima-Related Modifications ML13308A0072013-11-0101 November 2013 Open Phase Resolution Update Meeting Duke Energy Entitled Open Phase Detection and Protection. ML13275A2692013-10-0303 October 2013 10/3/13 Presentation Slides from Meeting with Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3, Protected Service Water Alternate Cooling ML13275A2252013-09-24024 September 2013 9/24/13 Meeting Slides from Meeting with Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3, Jocassee Dam Seismic Analysis ML13239A3372013-08-27027 August 2013 NRC Meeting Slides, Oconee Major Project Meeting - August 28, 2013 ML13239A3402013-08-27027 August 2013 Presentation for NRC Projects ML13099A4472013-04-10010 April 2013 Slides from Meeting with Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3, Milestones for Corrective Actions for an Apparent Violation of a License Condition on Fire Protection ML13095A2132013-04-0909 April 2013 Slides from Meeting with Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3, External Flood Reevaluation ML13123A2042013-03-25025 March 2013 Slides from Meeting with Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3, Concerning the Flooding Hazard Reevaluation Report ML13064A1022013-03-0505 March 2013 Slides from Predecisional Enforcement Conference with Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3, Apparent Violation of a License Condition on Fire Protection ML13056A1042013-02-0606 February 2013 Briefing Slides on the Fliod Scenario Rupture of Jocassee Dam ML13056A1032013-02-0606 February 2013 Briefing on Draft Information Notice - Potential Nonconservative Screening Value for Dam Failure Frequency in Probabilistic Risk Assessments. ML13056A1022013-02-0606 February 2013 Meeting Slides on Oconee Flood Issue Jocassee Dam Failure Frequency ML13056A0992013-02-0606 February 2013 Meeting Slides on Oconee Ssf Flood Barrier Breach Sdsp - Lessons Learned ML13052A7822013-02-0606 February 2013 Slides on Oconee Ssf Flood Barrier Breach SDP - Lessons Learned ML13035A2442013-01-30030 January 2013 Projects Meeting - NRC Slides ML13035A2332013-01-30030 January 2013 Projects Meeting - Licensee'S Public Meeting Slides 2022-09-14
[Table view] |
Text
NRR Briefing
Title:
Oconee Flood Protection (NRR/DRA)
Category: Status
Background:
Adequacy of Flood Protection for Standby Shutdown Facility (SSF) Given Failure of the Jocassee Dam Due to its configuration on Lake Keowee, the Oconee three-unit site relies entirely on accident mitigation from the Standby Shutdown Facility (SSF) to provide RCP seal cooling, inventory control, and secondary side heat removal under several conditions including a site flood from rupture of the upstream Jocassee Pumped Storage Dam. In 2006, the staff using the Significance Determination Process (SDP) evaluated a performance deficiency of an unanalyzed opening made in the SSF rendering it vulnerable to external flood. The licensee appealed the finding twice. During a re-evaluation on the second appeal, the staff discovered that the licensee had erroneously computed a random Jocassee Dam rupture frequency that was significantly lower than what should have been based on actual data.
In the 1980s, the licensee had performed a flooding analysis which predicted a resultant flood height of 4.71 feet given Jocassee Dam rupture. This study was used to justify constructing a seismically qualified 5-foot flood protection wall around the entrance to the SSF and was incorporated into the FSAR becoming part of their-licensing basis. ff-the eany 1990,, due to a nationai response plan, the Federal Energy KegdMliory Commission (FERC) with the licensee oerformed a flood analysi w.ii* o.- cte3 flood height of between 12 and 16 feet. In 1992, the licensee removed the 5-ft wall and Jocassee rupture flood ptcection reTerehrc*rT~ttr their iibensing basis using a potentially inappropriate argument. The earlier flooding study which predicted a 4.71-foot flood height is not available. Only the latter FERC flood analysis is available which clearly demonstrates that the current wall does not provide adequate flood protection.
Another discrepancy relates to the lower Jocassee Dam rupture frequency which is referenced in several documents including the Oconee Individual Plant Examination of External Events (IPEEE) and license renewal Severe Accident Mitigation Alternatives (SAMA) submittals. Moreover, other licensees with similar dam rupture vulnerabilities might have adopted this rupture frequency and used it to justify screening out consideration of external flood damage at their sites. Since the extent and impact at the individual sites of this underestimate is unknown, the staff will communicate concerns of potential deficiencies with licensees. Licensees may be required to re-visit flooding calculations to ensure validity.
SuccesseslAccomplishments:
A draft action plan has been prepared, is partially underway, and stakeholders have been identified. A team was assembled initially with personnel from DRA, DE, DORL, and DPR to consider several options on how to proceed. Staff and management meet regularly and provide progress to the ADES. A preliminary averted cost estimate for use in a regulatory analysis has been performed. A draft Information Notice has been written. Potential stakeholders have been briefed through various presentations made to the ET/LT, inter-office Risk Management Team (RMT), DRA staff, and NSIR.
Plans and Schedules:
One option is to address the removal of SSF flood protection references from the licensing basis and require the licensee to re-instate the wall in the licensing basis. The second option considered compliance using the backfit rule, 10 CFR 109. The staff is investigating whether a backfit regulatory analysis needs to be done. In either case, the licensee only has the current FERC study. In order to comply with the requirements of adequate flood protection, compensatory measures need to be taken by the licensee to protect the SSF beyond the 5-foot level. A third option was to simultaneously use the first two options with a heavier emphasis on the backfit aspect. The team will also assess issuing an order following the guidance of LIC-504, "Integrated Risk-Informed Decision-Making Process for Emergent Issues".
Contacts: Mike Franovich 415-1185 or Jeff Circle 415-1152.