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Category:Memoranda
MONTHYEARML24107B1272024-04-22022 April 2024 Ft. Calhoun Meeting Summary of March 27, 2024 Meeting with Omaha Public Power District on Submittal of Phase 1 Final Status Surveys ML22333B0922022-12-21021 December 2022 FY22 Nmss/Duwp Operating Experience Report ML21271A5992021-08-0303 August 2021 License Amendment Request (LAR) 21-01, Chapter 8, 12, Omaha Public Power District, FCS-SAF-103, FCS Deconstruction Health and Safety Plan CAC2 ML21055A4022021-05-14014 May 2021 Memorandum: Final Environmental Assessment and Finding of No Significant Impact of Initial and Updated Decommissioning Funding Plans for the Cooper, Fort Calhoun and Virgil C. Summer Independent Spent Fuel Storage Installations ML21271A1492021-04-13013 April 2021 License Amendment Request (LAR) 21-01, Chapter 1 9 Haley & Aldrich, Inc. Memorandum to Energysolutions, File No. 0127960-006, Fort Calhoun Nuclear Power Statio~1 ML20056E4872020-02-26026 February 2020 Staff Review of Fort Calhoun Independent Spent Fuel Storage Installation Physical Security Plan, Security Training and Qualification Plan, and Safeguard Contingency Plan, Revision 0 and the Verification of Additional Security Measures (ASM) ML18173A0082018-06-20020 June 2018 Cancelling Numerous Inspection Report Numbers ML18108A1212018-04-11011 April 2018 American Nuclear Insurers - Notification of Change in the Number of Power Reactors in the Secondary Financial Protection (SFP) Program ML17275A2642017-11-21021 November 2017 Safety Evaluation Input on Fort Calhoun Station Request for Approval of Permanently Defueled Emergency Plan and Emergency Action Level Scheme, Docket No. 50-285 ML16057A1232016-02-26026 February 2016 Cy 2015 Baseline Completion ML16007A4942016-01-11011 January 2016 Review of the Updated Final Safety Analysis Report for the Period June 14, 2014 Through December 4, 2015 ML14163A0022014-06-16016 June 2014 Summary of Audit Conducted March 5-9, 2012, Request to Adopt National Fire Protection Association (NFPA) 805, Performance-Based Standard for Fire Protection for LWR Electric Generating Plants ML14129A4452014-05-12012 May 2014 5/13/2014 Notice of Forthcoming Closed Meeting to Discuss Dam Failure Analysis for Cooper Nuclear Station and Fort Calhoun Station, Unit 1 ML14114A7012014-04-24024 April 2014 Task Interface Agreement - Concurrence on Fort Calhoun Tornado Missile Protection Licensing Basis (TIA 2013-07) ML14085A1842014-03-28028 March 2014 Final Fort Calhoun Gothic TIA Response ML14016A2602014-01-28028 January 2014 Fc Final Containment Structural TIA ML13351A4762013-12-16016 December 2013 Recommendation for NRC to Close Confirmatory Action Letter EA-13-020 Supporting the Restart of Fort Calhoun Station and Recommendation to Issue Post-Restart Confirmatory Action Letter ML13346A0822013-12-12012 December 2013 Notice of Forthcoming Closed Meeting to Discuss Dam Failure Analysis for Cooper Nuclear Station and Fort Calhoun Station, Unit 1 ML13312A8522013-11-0808 November 2013 Meeting Notice with Public to Discuss Fort Calhoun Station ML13253A3542013-09-27027 September 2013 Letter to R. Morris Information Exchange Pertaining to Health Issues Related to Crow Butte Resources Uranium Mine and Ft. Calhoun Nuclear Generating Station ML13102A1892013-04-15015 April 2013 4/22/12 Notice of Closed Meeting with Omaha Public Power District to Discuss Flooding Issues Associated with Fort Calhoun, Unit 1 ML13101A2232013-04-11011 April 2013 Meeting Notice with Omaha Public Power District - Potential License Amendment Requests for Fort Calhoun, Unit 1 Related to Flood Protection for Raw Water System, Tornado Missile Protection, Piping/Code Use, and Alternate Seismic Criteria ML13066A8772013-03-0707 March 2013 Issuance of Revised U.S. Nuclear Regulatory Commission Manual Chapter 0350 Panel Fort Calhoun Station Restart Checklist Basis Document ML13046A3212013-02-19019 February 2013 Notice of Closed Meeting with Fort Calhoun to Discuss Safeguards Information, Proprietary, or Other Sensitive Information ML12345A2702012-11-30030 November 2012 Revised 12/12/2012 Notice of Forthcoming Meeting with Omaha Public Power District to Discuss Containment Internal Structures Issues to Support Restart of Fort Calhoun Station, Unit 1 ML12335A1652012-11-30030 November 2012 Forthcoming Meeting with Omaha Public Power District to Discuss Containment Internal Structures Issues to Support Restart of Fort Calhoun Station, Unit 1 ML12318A3192012-11-13013 November 2012 Issuance of U.S. Nuclear Regulatory Commission Manual Chapter 0350 Panel Fort Calhoun Station Restart Checklist Basis Document ML12251A3172012-09-0707 September 2012 Manual Chapter 0350 Oversight Panel Charter - Revision ML12066A0302012-03-29029 March 2012 Closure Memorandum: Issue for Resolution 2011-001 Fort Calhoun - Failure to Maintain External Flooding Procedures. ML12229A1842012-03-0606 March 2012 Backfit Panel Regarding Fort Calhoun Flooding ML1134707162011-12-13013 December 2011 Memo to M.S.Virgilio Notification of Change to Regulatory Oversight of Fort Calhoun Station ML11293A1982011-10-19019 October 2011 Charter for Backfit Panel on Postulated Failure of Upstream Dams Affecting Fort Calhoun Station ML1118811312011-07-0707 July 2011 Docketing of Nonproprietary Information Provided by Omaha Public Power District (OPPD) Personnel Following the June 2, 2011, Regulatory Conference ML13106A1702011-07-0101 July 2011 Proposed Adequate Protection Backfit Exception ML11174A2322011-06-21021 June 2011 for the Record-06-21-2011: NRC Ensures Public Safety Through Rigorous Oversight of Nuclear Power Plant Safety Standards ML1113807322011-05-18018 May 2011 Regulatory Conference with Omaha Public Power ML1113306432011-05-16016 May 2011 Notice of Forthcoming Prelicensing Teleconference on 5/26/11 with Omaha Public Power District Related to Fort Calhoun Station, Unit 1's License Amendment Submittal Related to Transition to Risk-Informed NFPA-805 ML1109103272011-04-0505 April 2011 Verbal Authorization, Request for Relief from Code Case N-722 Visual Examination of the Reactor Vessel Hot-Leg Nozzle-to-Safe-End Dissimilar Metal Welds, 4th 10-Year Inservice Inspection Interval ML1108106952011-03-23023 March 2011 Notice of Forthcoming Pre-Licensing Meeting with Omaha Public Power District to Discuss Its Plans to Submit an Extended Power Uprate for Fort Calhoun Station and Issues Related to Equipment Environmental Qualification ML1104808672011-02-18018 February 2011 03/2/2011 Notice of Forthcoming Closed Pre-Licensing Teleconference with Omaha Public Power District to Discuss Its Plans to Submit an Extended Power Uprate for Fort Calhoun Station and Issues Related to Control Rod Withdrawal at Power ML1035605482010-12-23023 December 2010 Notice of Forthcoming Pre-Licensing Meeting with Omaha Public Power District to Discuss Fort Calhoun Station'S Extended Power Uprate, Spent Fuel Pool Criticality, and Proposed License Amendment Request Modeled After TSTF-493 ML1020701262010-08-30030 August 2010 the Nuclear Regulatory Commission Staff Spot-Check Review of Fort Calhoun Station Unit 1, June 30, 2010 - Finding of No Potential Issues in Bank Statements ML1016205062010-06-14014 June 2010 Notice of Forthcoming Teleconference Meeting with Omaha Public Power District to Discuss NRC Staff Request for Additional Information Dated 2/12/2010 on Generic Letter 2004-02 for Fort Calhoun Station, Unit 1 ML1006010322010-03-0101 March 2010 Cy 2009 Baseline Inspection Completion ML1004302742010-02-12012 February 2010 Notice of Forthcoming Teleconference with Omaha Public Power District to Discuss NRC Staff Request for Additional Information on Generic Letter 2004-02 for Fort Calhoun Station, Unit 1 ML0909607752009-04-0606 April 2009 Notice of End-of-Cycle Meeting with Omaha Public Power District - Fort Calhoun Station to Present and Discuss the Performance Results for the Fort Calhoun Station for the Period of January 1 Though December 31, 2008 ML0901504382009-01-16016 January 2009 Notice of Forthcoming Meeting with Omaha Public Power District, to Discuss Oppd'S Plans to Submit an Extended Power Uprate Request for the Fort Calhoun Station, Unit 1 ML0901603362009-01-16016 January 2009 Notice of Forthcoming Meeting with Omaha Public Power District, to Discuss the Fort Calhoun Station'S Transition to National Fire Protection Association (NFPA) 805 ML0814100052008-06-0303 June 2008 Summary of Conference Call with Omaha Public Power District (OPPD) Regarding OPPD Emergency Relief Request Submitted May 15, 2008 for Fort Calhoun Station (Tac No. MD8722) ML0809404512008-04-18018 April 2008 Summary of 12/6/2006 Meeting with Omaha Public Power District, Regarding Water Management Strategies for Resolution of GSI-191 (Tac No MD5780) 2024-04-22
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February 20, 207MEMORANDUM TO:Michael S. Peck, Senior Resident Inspector, CallawayFROM:Dwight D. Chamberlain, Director, Division of Reactor Safety /RA/
SUBJECT:
SPECIAL INSPECTION CHARTER TO EVALUATE THE FORTCALHOUN STATION ABB CIRCUIT BREAKER FAILURESA Special Inspection Team is being chartered in response to the Fort Calhoun Stationsafety-significant ABB circuit breaker failures. An ABB breaker failed during the starting sequence for the 'B' raw water pump on January 25, 2007. The apparent cause was determined to be a broken linkage/connector arm in the ABB circuit breaker mechanism operated cell (MOC). On Feb. 8, a second of their four (4) raw water pumps failed due to breakage of the same linkage arm. Because of the common cause aspect of this failure, the licensee declared 3 of the 4 pumps (all except 'B,' which was repaired and returned to service on January 31) inoperable, which placed them in a 6-hour shutdown action (see NRC Event 43157) due to operation outside their technical specifications. This represented a potential common-mode failure concern for the raw water pump circuit breakers, as well as other 4160 volt breakers in safety-related applications at Fort Calhoun Station. The other potentially affected breakers include those for both low pressure safety injection pumps, the motor-driven auxiliary feedwater pump, the normal and alternate feeder breakers to the 4160 volt busses, and the feeder breakers from the 4160 volt busses to the 480 volt safety busses. Nonsafety-related buses and components may be affected as well (e.g., the feeder breakers to the nonsafety-related 4160 buses). The assigned Senior Reactor Analyst to support the team is Russ Bywater.A.BasisOn both January 25 and February 8, 2007, identical ABB circuit breakers for FortCalhoun Station raw water pumps failed due to the same apparent cause. As stated previously, there are also other Fort Calhoun Station safety-significant breakers that may have this problem. This represents the potential of a significant common mode concern, as well as a potential generic issue. The combined deterministic criteria and risk evaluation, conducted under NRC MD 8.3, indicate supplemental inspection of this issue is warranted.A Region IV Senior Reactor Analyst completed a preliminary estimate of the incrementalconditional core damage probability for this condition using the SPAR model for Fort Michael S. Peck-2-Calhoun Station, Revision 3.31, and methods identified in the Risk AssessmentStandardization Project (RASP) Handbook for performing Management Directive 8.3 assessments. Accounting for the plant conditions and configurations resulted in an incremental conditional core damage probability of 1.17E-6.The licensee believes the cause of the ABB circuit breaker/MOC failures is most likelyhigh-cycle fatigue of the linkage/connector arm. They also believe the potential adverse condition of the component only occurs after more than 1,000 cycles of the breaker.
However, this is yet to be substantiated. The licensee has sent the two failed components to labs for analysis. Additionally, high-cycle fatigue may only be the failure mechanism, not the root cause of the problem. Additional factors, such as breaker alignment and adjustment, may significantly alter the expected number of cycles before failure. This is evidenced by one of the breakers failing at 1,200 cycles when the other three raw water pump breakers did not fail with 1,600 cycles. Therefore, additional inspection is important to gain a more comprehensive understanding of this issue and the underlying cause(s).This Special Inspection Team is chartered to review the circumstances related to thelicensee's ABB circuit breaker and MOC problems, and assess the effectiveness of the actions for resolving these problems. The team will also assess the potential for impact on other plant systems in addition to the raw water pumps and the potential for generic implications. The team will also assess the effectiveness of the immediate actions taken and the notifications made by the licensee in response to the pump failures that occurred on January 25 and February 8, 2007.B.ScopeThe team is expected to address the following:
1.Develop an understanding of the ABB circuit breaker original design, thedegraded conditions, and failures related to the raw water pump failures.2.Determine if the licensee's maintenance and monitoring programs were sufficientto maintain the ABB breakers/MOCs in their designed configuration and operating parameters.3.Assess licensee effectiveness in identifying previous ABB circuit breakerproblems, evaluating the cause of these problems, and implementation of corrective actions to resolve identified problems.4.Review plant equipment records to verify a complete listing of the potentiallyaffected breakers at the facility, the number of cycles of the components, and record keeping regarding transfer of operating data (cycles) when transferring parts from other breakers.5.Identify and assess additional actions planned by the licensee for other similarsafety-significant ABB circuit breakers at the facility.
Michael S. Peck-3-6.Assess the licensee's root cause evaluation, the extent of condition, and thelicensee's common mode evaluation and assess the adequacy of corrective actions including immediate and long-term actions.7.Evaluate pertinent industry operating experience and potential precursors to theJanuary 25 and February 8 breaker/MOC failures, including the effectiveness of licensee actions taken in response to any operating experience.8.Determine if there are any potential generic issues related to the failures of theABB circuit breakers/MOCs. Promptly communicate any potential generic issues to Region IV management.9.Determine if the technical specifications were met during the periods of each ofthe raw water pump failures.10.Collect data as necessary to support a risk analysis of the degraded conditionsand failures as appropriate.C.GuidanceInspection Procedure 93812, "Special Inspection," provides additional guidance to beused by the Special Inspection Team. Your duties will be as described in Inspection Procedure 93812. The inspection should emphasize fact-finding in its review of the circumstances surrounding the event. It is not the responsibility of the team to examine the regulatory process. Safety concerns identified that are not directly related to the event should be reported to the Region IV office for appropriate action.The Team will report to the site, conduct an entrance, and begin inspection no later thanFebruary 20, 2007. While on site, you will provide daily status briefings to Region IV management, who will coordinate with the Office of Nuclear Reactor Regulation, to ensure that all other parties are kept informed. A report documenting the results of the inspection should be issued within 30 days of the completion of the inspection.This Charter may be modified should the team develop significant new information thatwarrants review. Should you have any questions concerning this Charter, contact me at (817) 860-8180.
cc:J. Clark, C:DRP/E W. Jones, C:DRS/EB1 Michael S. Peck-4-SUNSI Review Completed: __Y______ ADAMS: Yes G No Initials: ___WBJ__ Publicly Available G Non-Publicly Available G Sensitive Non-SensitiveC:\FileNet\ML070530053.wpdML070530053C:EB1D:DRSWBJones/lmbDDChamberlain/RA//RA/2/18/072/20/07OFFICIAL RECORD COPY T=Telephone E=E-mail F=Fax