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Category:CORRESPONDENCE-LETTERS
MONTHYEARML20217N1931999-10-22022 October 1999 Forwards Insp Rept 50-298/99-12 on 990927-30.No Violations Noted.Insp Exam of Activities Under License as They Relate to Emergency Preparedness & to Compliance with Commission Rules & Regulations & with Conditions of License ML20217G8771999-10-14014 October 1999 Forwards Insp Rept 50-298/99-10 on 990920-24.No Violations Noted ML20217G7401999-10-14014 October 1999 Forwards MOR for Sept 1999 for Cooper Nuclear Station. Rept Includes Documentation of Challenges to Safety/Relief Valves,Iaw TS 5.6.4 ML20217C2671999-10-0808 October 1999 Forwards Insp Rept 50-298/99-03 on 990823-27 & 0907-10.No Violations Noted.Purpose of Insp to Ensure That Licensee Had Effective Programs for Identifying,Evaluating & Correcting Problems Which Could Impact Safe Plant Operations ML20212K9661999-09-30030 September 1999 Forwards Safety Evaluation Accepting plant-specific Safety Evaluation Rept for USI A-46 Program Implementation at Cooper Nuclear Station ML20216J1081999-09-28028 September 1999 Ltr Contract:Task Order 048, Cooper Safety Sys Design & Performance Capability Insp, Under Contract NRC-03-98-021 ML20212J5061999-09-27027 September 1999 Forwards Insp Rept 50-298/99-07 on 990718-0828.No Violations Noted.Inspectors Focused on Implementation of Licensee Reactor Safety & Emergency Preparedness Programs ML20212F3641999-09-22022 September 1999 Forwards Insp Rept 50-298/99-09 on 990823-26.No Violations Noted ML20216J8061999-09-20020 September 1999 Forwards Rev 37 to Safeguards Plan,Iaw Provisions of 10CFR50.(p).Rev Withheld,Per 10CFR73.21 ML20212C4921999-09-15015 September 1999 Forwards Monthly Operating Rept for Aug 1999 for Cooper Nuclear Station.Rept Includes Operating Data Rept,Unit SD Rept & Documentation of Challenges to Safety/Relief Valves ML20212A6061999-09-14014 September 1999 Forwards Insp Rept 50-298/99-08 on 9900816-20.No Violations Noted.Insp Focused on Implementation & Effective Performance of Access Authorization/Fitness-for-Duty (Behavior Observation) Program & Access Control of Personnel ML20211N5271999-09-0202 September 1999 Responds to NRC 990823 RAI Re Y2K Readiness at Cooper Nuclear Station,Per GL 98-01,Suppl 1 05000298/LER-1999-006, Forwards LER 99-006-00 for Cns.Commitments Made by Util Encl1999-08-26026 August 1999 Forwards LER 99-006-00 for Cns.Commitments Made by Util Encl ML20211F1311999-08-24024 August 1999 Forwards Rev 1 to Calculation Nedc 97-044, NPSH Margins for RHR & CS Pumps, in Support of 990615 Proposed Amend to DPR-46 Re Containment Overpressure Contribution to ECCS Pumps NPSH Requirements 05000298/LER-1999-003, Informs That Commitment Re Insp Rept 50-298/98-15 & LER 99-003,to Bound Extent of Condition & Take Appropriate C/As Is Now Complete.Addl Time Is Required to Accommodate Training of Engineering Support Personnel1999-08-23023 August 1999 Informs That Commitment Re Insp Rept 50-298/98-15 & LER 99-003,to Bound Extent of Condition & Take Appropriate C/As Is Now Complete.Addl Time Is Required to Accommodate Training of Engineering Support Personnel ML20211F4661999-08-23023 August 1999 Discusses GL 98-01 Issued by NRC on 980511 & NPPD Responses for Cooper Nuclear Station & 990628 & Results of Visit to Plant on 990811-12.Staff Determined That Integrated Contigency Plan Incomplete & CNS Not Y2K Ready ML20210R0301999-08-12012 August 1999 Forwards Monthly Operating Rept for July 1999 for Cooper Nuclear Station,Iaw Guidance Provided by GL 97-02.Rept Also Includes Documentation of Challenges to Srvs,Per TS 5.6.4 ML20211A9501999-08-12012 August 1999 Discusses 990720-21 Workshop Conducted in Region IV Ofc,Re Exchange of Info in Area of Use of Risk Insights in Regulatory Activities.List of Attendees,Summary of Topic & Issues,Agenda & Copies of Handouts Encl ML20210P6761999-08-10010 August 1999 Requests That Following Changes Be Made to Distribution on NRC Correspondence ML20210P6861999-08-0909 August 1999 Forwards Insp Rept 50-298/99-06 on 990530-0717.No Violations Noted.During Insp,Inspectors Identified Two Issues Categorized as Being Low Risk Significance & within Licensee Response Band ML20210N1331999-08-0606 August 1999 Forwards Notice of Withdrawal of Application for Amend to FOL DPR-46.By Ltr Licensee Withdrew Amend Request Which Would Have Revised Usfar to Reflect as-built Configuration of Reactor Bldg Isolation Dampers ML20210L1461999-08-0303 August 1999 Informs That NRC Plans to Administer Gfes of Written Operator Licensing Exam on 991006.Requests Submittal of Ltr Identifying Individuals Taking Exam,Personnel Allowed Access to Exams & Mailing Address for Exams ML20210K6071999-08-0202 August 1999 Submits Withdrawal of Proposed License Amend Re Secondary Containment Isolation Description & Refueling Accident Analysis Results ML20210K3811999-08-0202 August 1999 Forwards Listed Info,Which NPPD Believes Demonstrates Ability to Obtain Funds in Amount of $10 Million for Payment of Such Premiums within Specified Three Month Period,Iaw 10CFR140.21 ML20210G5101999-07-28028 July 1999 Forwards fitness-for-duty Program semi-annual Performance Rept for Period of 990101-0630,per Provisions of 10CFR26.71(d) ML20210D2541999-07-21021 July 1999 Forwards Insp Rept 50-298/99-02 on 990628-0702.Purpose of Insp Was Primarily to Evaluate Effectiveness of Licensed Operator Requalification Program.No Violations Were Identified ML20210C2041999-07-20020 July 1999 Discusses 990715 Mgt Meeting with Midamerican Energy Co Re risk-informed Baseline Insp Program Recently Implemented at Cooper & Fort Calhoun Stations ML20209H8191999-07-15015 July 1999 Forwards Safety Evaluation on GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves, for Cooper Nuclear Station ML20209E6951999-07-12012 July 1999 Discusses Response to RAI on GL 92-01,rev 1,suppl 1, Rv Structural Integrity. Recommends Review of New Database Diskettes on Listed Website.Comments Due by 990901 or Data Entered Into Rvid for Plant Will Be Acceptable ML20209D8731999-07-0808 July 1999 Refers to 990707 Meeting Re Licensee Recent Maintenance Program self-assessment.Also Discussed How Licensee Incorporated Assessment Findings Into Rev of Maintenance Performance Improvement Plan.List of Attendees Encl ML20209B7851999-07-0101 July 1999 Forwards Corrected Occupational Radiation Exposure Repts, for Cys 1996 & 1997.Util Stated That Repts Did Not Properly Tabulate Number of Personnel Receiving Exposures Less than 100 Mrem by Work & Job Functions in CY96 & CY97 05000298/LER-1999-005, Forwards LER 99-005-00 for Cns.Commitments Made by Util Encl1999-07-0101 July 1999 Forwards LER 99-005-00 for Cns.Commitments Made by Util Encl ML20196J2471999-06-29029 June 1999 Discusses Completion of Licensing Action for GL 97-04, Assurance of Sufficient Net Positive Suction Head for ECC & Containment Heat Removal Pumps, 05000298/LER-1999-004, Forwards LER 99-004-01.Commitments Made by Util Are Encl1999-06-28028 June 1999 Forwards LER 99-004-01.Commitments Made by Util Are Encl ML20209B5451999-06-28028 June 1999 Submits Response to NRC GL 98-01,Suppl 1, Y2K Readiness of Computer Sys at Nuclear Power Plants. Disclosure Encl ML20196H0331999-06-24024 June 1999 Informs NRC of Deletion of 1991 Commitment Contained in Ltr Re Feedwater Nozzle Bypass Leakage Monitoring at Plant ML20196F7511999-06-24024 June 1999 Discusses 990622 Meeting with Public at Arbor Manor, Alburn,Ne to Provide Overview of Pilot Insp Program ML20209A7221999-06-23023 June 1999 Submits Revised Pages to Proposed Change to Plant TS Previously Submitted in ,Per 990615 Telcon with NRC ML20196F5331999-06-22022 June 1999 Forwards Examination Summary Rept for FW Nozzle Examinations Performed During 1998 Fall Refueling Outage at Cooper Nuclear Station.Rept Covers Past Examinations Up to & Including 1998 Fall Refueling Outage ML20196B4681999-06-17017 June 1999 Forwards TS Bases Changes Made at Plant Subsequent to Receipt of License Amend 178,dtd 980731,for Conversion to Its,Through 990610.List of Effective Pages for TS Bases, Encl ML20196E1411999-06-16016 June 1999 Forwards Insp Rept 50-298/99-05 on 990502-29.Noncited Violations Identified ML20195H8891999-06-14014 June 1999 Forwards Response to NRC 990315 RAI Re GL 95-07, Pressure Locking & Thermal-Binding of SR Power-Operated Gate Valves, 180-day Response Submitted by District on 960213 ML20195F6171999-06-0909 June 1999 Informs That GE Rept, Matl Presented by GE 970709 Meeting at Cooper Nuclear Power Station Re Replacement of ECCS Pump Suction Strainers Between Nppd,Ge & NRC Staff, Will Be Withheld from Public Disclosure as Requested ML20207G3031999-06-0808 June 1999 Ack Receipt of Which Transmitted Changes to Cooper Nuclear Station EP Implementing Procedure EPIP 5.7.1, Emergency Classification,Rev 24,under 10CFR50,App E,Section V Provisions.No Violations Identified ML20195E2351999-06-0808 June 1999 Forwards Response to NRC 990517 RAI Re Util Proposed Change to TS Re Calibr Frequency of Reactor Recirculation Flow Transmitters Associated with APRM ML20207G4481999-06-0808 June 1999 Ack Receipt of Which Transmitted Changes to Cooper Nuclear Station EP Implementing Procedure,Epip 5.7.1, Emergency Classification,Rev 23 C2,under Provisions of 10CFR50,App E,Section V ML20207G3001999-06-0707 June 1999 Ack Receipt of Which Transmitted Changes to Cooper Nuclear Station Ep,Rev 33,under Provisions of 10CFR50,App E,Section V.No NRC Approval Required Based on Determination That EP Effectiveness Not Affected by Changes ML20207G4531999-06-0707 June 1999 Ack Receipt of Which Transmitted Changes to Cooper Nuclear Station EP Implementing Procedure EPIP 5.7.1, Emergency Classification,Revision 25,under Provisions of 10CFR50,App E,Section V ML20207D3811999-05-27027 May 1999 Informs That During Next 6 to 12 Months,Starting 990530,NRC Plans to Conduct Insps Shown in Attached Insp Plan.Insps Include Both Planned Baseline & Supplemental Insps (Formerly Core & Regional Initiative Insps) ML20207A5191999-05-19019 May 1999 Forwards Insp Rept 50-298/99-04 on 990321-0501.Four Violations Identified & Being Treated as non-cited Violations 1999-09-30
[Table view] Category:NRC TO UTILITY
MONTHYEARIR 05000298/19900291990-11-0909 November 1990 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/90-29 ML20217A3691990-11-0707 November 1990 Forwards Insp Rept 50-298/90-33 on 900904-1016.Violations Noted But Not Cited ML20058G1461990-11-0505 November 1990 Ack Receipt of Submitting Rev 13 to Emergency Plan.Changes Acceptable for Implementation.Commitment Date for Submission of Changes Is 901031 ML20058H0581990-11-0101 November 1990 Forwards List of Unimplemented Gsis,Per Generic Ltr 90-04 IR 05000298/19900251990-10-16016 October 1990 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/90-25 ML20059M8751990-10-0202 October 1990 Informs That Util Response to Generic Ltr (GL) 90-03, Relaxation of Staff Position in Generic Ltr 83-28,Item 2.2, Part 2 'Vendor Interface for Safety-Related Components,' Acceptable ML20059M7391990-09-28028 September 1990 Forwards Sys Entry & Retest Insp Rept 50-298/90-31 on 900910-14 & 17.No Violations or Deviations Noted ML20059M4651990-09-27027 September 1990 Forwards Insp Rept 50-298/90-30 on 900827-31 & Notice of Violation ML20059E2691990-08-31031 August 1990 Forwards Safety Evaluation Granting Licensee 900525 Relief Requests RP-14 & RP-15 for Relief from Requirements to Measure Pump Inlet Pressure & Instrument Ranges, Respectively ML20058P4151990-08-0808 August 1990 Forwards Insp Rept 50-298/90-26 on 900616-0715.No Violations or Deviations Noted ML20056A1701990-07-30030 July 1990 Advises That Written Licensing Exams Scheduled on 901119 & Operating Licensing Exams Scheduled on 901120.Preliminary Applications Should Be Submitted at Least 30 Days Prior to Exam Date to Review Training & Experience of Candidates ML20055J2301990-07-24024 July 1990 Forwards Insp Rept 50-298/90-27 on 900709-13.No Violations or Deviations Noted.Actions Taken Re Previous Insp Findings Examined ML20055G8751990-07-20020 July 1990 Forwards Insp Rept 50-298/90-20 on 900611-15 & 25-29.No Violations or Deviations Noted ML20055G1841990-07-18018 July 1990 Confirms 900720 Mgt Meeting in Region IV Ofc Re Emergency Actions Levels,Annual Exercise & Emergency Preparedness Program Enhancements ML20055E6841990-07-0909 July 1990 Discusses Generic Implications & Resolution of Control Element Assemblies at Plant.Util Should Submit Plans & Justification for Any Continued Use of Old Style Control Element Assemblies Beyond Current Cycle for NRC Review ML20055D9441990-07-0505 July 1990 Forwards Insp Rept 50-298/90-22 on 900516-0615.No Violations or Deviations Noted.Actions Taken W/Regard to Previously Identified Insp Findings Examined IR 05000298/19900121990-06-28028 June 1990 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/90-12 IR 05000298/19900051990-06-27027 June 1990 Ack Receipt of Informing NRC That Util Evaluated Observation Re Vital Area Key Control,Per Insp Rept 50-298/90-05.Initiatives to Delineate Responsibilities for Vital Key Exchange During Shift Turnover Appropriate ML20055C7741990-06-18018 June 1990 Forwards Insp Rept 50-298/90-18 on 900416-0515.No Violations or Deviations Noted ML20059M9251990-06-13013 June 1990 Forwards NRC Performance Indicators for First Quarter 1990. W/O Encl ML20248H2791989-10-0606 October 1989 Forwards Comments from Bnwl Re Util Scenario for Exercise Planned on 891025 IR 05000298/19890251989-10-0505 October 1989 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/89-25 ML20248E8151989-10-0202 October 1989 Confirms 890926 Telcon Re Change of Dates for Maint Team Insp Preparation Meetings from 891023-25 to 891031-1102 ML20247Q6071989-09-21021 September 1989 Forwards Amend 11 to Indemnity Agreement B-57,reflecting Changes to 10CFR140, Financial Protection Requirements & Indemnity Agreements, for Signature IR 05000298/19890291989-09-19019 September 1989 Forwards Insp Rept 50-298/89-29 on 890801-31.No Violations Noted IR 05000298/19890161989-09-14014 September 1989 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/89-16. Implementation of Corrective Actions Will Be Reviewed During Future Insp IR 05000298/19890061989-09-13013 September 1989 Discusses Insp Rept 50-298/89-06 on 890206-10 & Forwards Notice of Violation.Concerns Raised Re Various Failures to Log or Rept Security Incidents.Decision Re Ofc of Investigations Findings Will Be Sent Separately ML20247G8531989-09-12012 September 1989 Forwards Insp Rept 50-298/89-24 on 890731-0804 & Notice of Deviation ML20247D4731989-09-0606 September 1989 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/89-22 ML20247C0581989-09-0505 September 1989 Forwards Insp Rept 50-298/89-27 on 890821-25.No Violations or Deviations Noted ML20247G8051989-08-30030 August 1989 Forwards Summary of 890712 Meeting W/Util Re SALP for 880201-890415.Util 890811 Response to SALP Also Encl ML20247B3801989-08-30030 August 1989 Summarizes 890818 Region Iv/Senior Util Executives Meeting in Arlinton,Tx Re General Matters on Topics Discussed, Including SALP Process in Region 4.List of Attendees & Agenda Encl ML20246H9501989-08-28028 August 1989 Forwards Insp Rept 50-298/89-26 on 890717-21.No Violations or Deviations Noted ML20246F8171989-08-25025 August 1989 Forwards Insp Rept 50-298/89-30 on 890807-11.Violations Noted,But No Citation Issued ML20246G1341989-08-22022 August 1989 Documents NRC 890810 Meeting W/Licensee,Including H Parris & Staff in Region IV Ofc to Discuss General Issues of Interest to Licensee & Nrc,Region Iv.Topics Covered During Licensee Presentation Described ML20246G3201989-08-22022 August 1989 Forwards Insp Rept 50-298/89-25 on 890701-31 & Notice of Deviation ML20246E1291989-08-21021 August 1989 Forwards Insp Rept 50-298/89-28 on 890731-0804 & Notice of Violation.Response to One of Two Violations Required ML20245K9991989-08-11011 August 1989 Confirms 890808 Conversation in Which Util Agreed to Participate in 891012 NRC Regulatory Impact Survey.Info Re Survey Provided ML20245J7291989-08-0909 August 1989 Advises of Maint Team Insp Scheduled for Wks of 891113-1204, Per 890807 Telcon.Purpose of Meetings Is to Define Scope of Insp,To Discuss Interfaces Between Team & Staff & to Receive Info to Support Badging Team Members for Unescorted Access ML20245H1131989-08-0404 August 1989 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/89-18 ML20248C2121989-08-0303 August 1989 Ack Receipt of in Response to 890608 Notice of Violation Re Insp Rept 50-298/89-19.Util Basis for Denial of Violation Not Substantiated & NRC Concludes That Violation Did Occur IR 05000298/19880291989-07-27027 July 1989 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/88-29 ML20247M1671989-07-27027 July 1989 Forwards Insp Rept 50-298/89-21 on 890626-30.No Violations or Deviations Noted ML20236E6561989-07-24024 July 1989 Forwards Insp Rept 50-298/89-23 on 890626-30.No Violations or Deviations Noted ML20247L9501989-07-24024 July 1989 Forwards Insp Rept 50-298/89-22 on 890601-30 & Notice of Violation ML20246M4961989-07-11011 July 1989 Provides Agenda for 890809 Meeting of Senior Util Executives Sponsored by Region IV at Univ of Texas.Recipient Scheduled to co-lead Discussion of SALP Process W/J Milhoan ML20246N2051989-07-10010 July 1989 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/89-17 ML20246A7091989-06-22022 June 1989 Forwards Insp Rept 50-298/89-18 on 890416-0531 & Notice of Violation.Nrc Considers Inadequate Station Mod Work Instructions Significant.Other Weaknesses in Plant Mod Process Identified in Paragraph 6 in Insp Rept ML20245K5371989-06-22022 June 1989 Forwards NRR Ack Receipt of Petition Filed by Ecology Ctr of Southern California & Stating That Petition Being Treated Under 10CFR2.206 of NRC Regulations ML20245B5591989-06-20020 June 1989 Forwards SALP Board Rept 50-298/89-12 for 880201-890415.NRC Pleased Overall,Although Sys for Identifying to Mgt Areas Where Corrective Actions Needed Should Be Improved 1990-09-28
[Table view] Category:OUTGOING CORRESPONDENCE
MONTHYEARML20217N1931999-10-22022 October 1999 Forwards Insp Rept 50-298/99-12 on 990927-30.No Violations Noted.Insp Exam of Activities Under License as They Relate to Emergency Preparedness & to Compliance with Commission Rules & Regulations & with Conditions of License ML20217G8771999-10-14014 October 1999 Forwards Insp Rept 50-298/99-10 on 990920-24.No Violations Noted ML20217C2671999-10-0808 October 1999 Forwards Insp Rept 50-298/99-03 on 990823-27 & 0907-10.No Violations Noted.Purpose of Insp to Ensure That Licensee Had Effective Programs for Identifying,Evaluating & Correcting Problems Which Could Impact Safe Plant Operations ML20212K9661999-09-30030 September 1999 Forwards Safety Evaluation Accepting plant-specific Safety Evaluation Rept for USI A-46 Program Implementation at Cooper Nuclear Station ML20216J1081999-09-28028 September 1999 Ltr Contract:Task Order 048, Cooper Safety Sys Design & Performance Capability Insp, Under Contract NRC-03-98-021 ML20212J5061999-09-27027 September 1999 Forwards Insp Rept 50-298/99-07 on 990718-0828.No Violations Noted.Inspectors Focused on Implementation of Licensee Reactor Safety & Emergency Preparedness Programs ML20212F3641999-09-22022 September 1999 Forwards Insp Rept 50-298/99-09 on 990823-26.No Violations Noted ML20212A6061999-09-14014 September 1999 Forwards Insp Rept 50-298/99-08 on 9900816-20.No Violations Noted.Insp Focused on Implementation & Effective Performance of Access Authorization/Fitness-for-Duty (Behavior Observation) Program & Access Control of Personnel ML20211F4661999-08-23023 August 1999 Discusses GL 98-01 Issued by NRC on 980511 & NPPD Responses for Cooper Nuclear Station & 990628 & Results of Visit to Plant on 990811-12.Staff Determined That Integrated Contigency Plan Incomplete & CNS Not Y2K Ready ML20211A9501999-08-12012 August 1999 Discusses 990720-21 Workshop Conducted in Region IV Ofc,Re Exchange of Info in Area of Use of Risk Insights in Regulatory Activities.List of Attendees,Summary of Topic & Issues,Agenda & Copies of Handouts Encl ML20210P6861999-08-0909 August 1999 Forwards Insp Rept 50-298/99-06 on 990530-0717.No Violations Noted.During Insp,Inspectors Identified Two Issues Categorized as Being Low Risk Significance & within Licensee Response Band ML20210N1331999-08-0606 August 1999 Forwards Notice of Withdrawal of Application for Amend to FOL DPR-46.By Ltr Licensee Withdrew Amend Request Which Would Have Revised Usfar to Reflect as-built Configuration of Reactor Bldg Isolation Dampers ML20210L1461999-08-0303 August 1999 Informs That NRC Plans to Administer Gfes of Written Operator Licensing Exam on 991006.Requests Submittal of Ltr Identifying Individuals Taking Exam,Personnel Allowed Access to Exams & Mailing Address for Exams ML20210D2541999-07-21021 July 1999 Forwards Insp Rept 50-298/99-02 on 990628-0702.Purpose of Insp Was Primarily to Evaluate Effectiveness of Licensed Operator Requalification Program.No Violations Were Identified ML20210C2041999-07-20020 July 1999 Discusses 990715 Mgt Meeting with Midamerican Energy Co Re risk-informed Baseline Insp Program Recently Implemented at Cooper & Fort Calhoun Stations ML20209H8191999-07-15015 July 1999 Forwards Safety Evaluation on GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves, for Cooper Nuclear Station ML20209E6951999-07-12012 July 1999 Discusses Response to RAI on GL 92-01,rev 1,suppl 1, Rv Structural Integrity. Recommends Review of New Database Diskettes on Listed Website.Comments Due by 990901 or Data Entered Into Rvid for Plant Will Be Acceptable ML20209D8731999-07-0808 July 1999 Refers to 990707 Meeting Re Licensee Recent Maintenance Program self-assessment.Also Discussed How Licensee Incorporated Assessment Findings Into Rev of Maintenance Performance Improvement Plan.List of Attendees Encl ML20196J2471999-06-29029 June 1999 Discusses Completion of Licensing Action for GL 97-04, Assurance of Sufficient Net Positive Suction Head for ECC & Containment Heat Removal Pumps, ML20196F7511999-06-24024 June 1999 Discusses 990622 Meeting with Public at Arbor Manor, Alburn,Ne to Provide Overview of Pilot Insp Program ML20196E1411999-06-16016 June 1999 Forwards Insp Rept 50-298/99-05 on 990502-29.Noncited Violations Identified ML20195F6171999-06-0909 June 1999 Informs That GE Rept, Matl Presented by GE 970709 Meeting at Cooper Nuclear Power Station Re Replacement of ECCS Pump Suction Strainers Between Nppd,Ge & NRC Staff, Will Be Withheld from Public Disclosure as Requested ML20207G3031999-06-0808 June 1999 Ack Receipt of Which Transmitted Changes to Cooper Nuclear Station EP Implementing Procedure EPIP 5.7.1, Emergency Classification,Rev 24,under 10CFR50,App E,Section V Provisions.No Violations Identified ML20207G4481999-06-0808 June 1999 Ack Receipt of Which Transmitted Changes to Cooper Nuclear Station EP Implementing Procedure,Epip 5.7.1, Emergency Classification,Rev 23 C2,under Provisions of 10CFR50,App E,Section V ML20207G4531999-06-0707 June 1999 Ack Receipt of Which Transmitted Changes to Cooper Nuclear Station EP Implementing Procedure EPIP 5.7.1, Emergency Classification,Revision 25,under Provisions of 10CFR50,App E,Section V ML20207G3001999-06-0707 June 1999 Ack Receipt of Which Transmitted Changes to Cooper Nuclear Station Ep,Rev 33,under Provisions of 10CFR50,App E,Section V.No NRC Approval Required Based on Determination That EP Effectiveness Not Affected by Changes ML20207D3811999-05-27027 May 1999 Informs That During Next 6 to 12 Months,Starting 990530,NRC Plans to Conduct Insps Shown in Attached Insp Plan.Insps Include Both Planned Baseline & Supplemental Insps (Formerly Core & Regional Initiative Insps) ML20207A5191999-05-19019 May 1999 Forwards Insp Rept 50-298/99-04 on 990321-0501.Four Violations Identified & Being Treated as non-cited Violations ML20206Q6171999-05-17017 May 1999 Forwards RAI Re 990301 & 10 Ltrs Re Proposed TS Changes to Calibr Frequency of Recirculation Flow Transmitters from Once Every 184 Days to Once Every 18 Months.Util Responses Should Be Provided within 30 Days of Ltr Date ML20206P0171999-05-12012 May 1999 Discusses GL 96-05 Issued on 960918 & NPPD Responses Submitted on 961118,970317,980504 & 990222 for Cooper Nuclear Station.Forwards Safety Evaluation Concluding That NPPD Adequately Addressed Actions Requested in GL 96-05 IR 05000298/19980091999-05-12012 May 1999 Refers to Insp Rept 50-298/98-09 Conducted Between 981227-990130.During Insp,Apparent Violation of 10CFR50.50 Identified & Being Treated as non-cited ML20206M1791999-05-11011 May 1999 Informs That NRC Ofc of NRR Reorganized Effective 990328. Reorganization Chart Encl ML20206H4191999-05-0707 May 1999 Informs That on 990407,NRC Administered Gfes of Written Operator Licensing Exam.Licensee Facility Did Not Participate in Exam,However,Copy of Master Exam with Answer Key,Encl for Info.Without Encl ML20206P8961999-05-0707 May 1999 Refers to Meeting Conducted at Region IV Office on 990506 Re Licensee Upcoming Rev to Strategy for Achieving Engineering Excellence & Plans to Achieve Performance Improvements.List of Attendees & Util Presentation,Encl ML20206H7541999-05-0505 May 1999 Forwards Insp Rept 50-298/99-01 on 990207-0320.Violations Being Treated as non-cited Violations ML20205R5541999-04-16016 April 1999 Submits Summary of 990330 Public Meeting in Brownville,Ne to Discuss Results of PPR Completed on 990211,which Allowed for Exchange on New Assessment Process,Current Performance Review & Upcoming Actions Taken in Response to Y2K Concerns IR 05000298/19980221999-03-19019 March 1999 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-298/98-22 on 990107.Finds Reply Responsive to Concerns Raised in NOV ML20205E8991999-03-19019 March 1999 Advises of Completion of Plant Performance Review on 990209 to Develop Integrated Understanding of Safety Performance. Overall Performance Was Acceptable.Problems with Communication in CR Resulted in Several Minor Events ML20204D9451999-03-18018 March 1999 Forwards Insp Rept 50-298/98-09 on 981227-990206.Three Violations Identified & Being Treated as Noncited Violations,Consistent with App C of Enforcement Policy ML20207M9591999-03-15015 March 1999 Forwards Request for Addl Info Re Licensee Response to GL 95-07, Pressure-Locking & Thermal-Binding of Safety-Related Power-Operated Gate Valves, for Cooper Nuclear Station ML20204B6771999-03-15015 March 1999 Submits Withdrawal of Amend Request for Operating License DPR-46.Proposed Change Would Have Modified Facility TSs Pertaining to Neutron Monitoring Neutron Detectors ML20207M9811999-03-15015 March 1999 Advises That Which Withdrew 980415 Amend Request, Being Treated as Withdrawal.Proposed Change Would Have Modified Facility TSs Pertaining to Neutron Monitoring,Flow Biased Rod Block Monitor ML20204B3301999-03-11011 March 1999 Forwards SE Accepting Third 10-year Interval Inservice Insp Program Plan Requests for Relief Numbers RI-13,RI-17 & RI-25 for Plant ML20204B7061999-03-11011 March 1999 Requests Approval of Proposed Operability Criteria for Use in Evaluation & Interim Resolution of Degraded & Nonconforming Conditions with Piping & Pipe Supports at Facility ML20205A5811999-03-0909 March 1999 Forwards Exam Rept 50-298/99-301 for Exam Administered on 990212.Exam Included Evaluation of Four Applicants for Reactor Operator License ML20207K3231999-03-0808 March 1999 Discusses 990224 Meeting Re Staff Critique of Refueling & Equipment Outage RE-18 & Implementation Status of Improvement Strategy for Engineering.List of Attendees & Matl Used in Presentation Encl ML20202G1701999-02-0202 February 1999 Informs That NRC Plans to Administer Generic Fundamentals Exam Section of Written Operator Licensing Exam at Util Facility on 990407.Authorized Representative from Facility Must Submit Ltr Listing Names of Candidates ML20202E3121999-01-22022 January 1999 Forwards Insp Rept 50-298/98-08 on 981115-1226 & Notice of Violation.First Violation Re Staff Failure to Follow Procedures (Two in Operations,One in Maint & One in Plant Support) ML20199G6041999-01-19019 January 1999 Informs That Effective 990118,JN Donohew Has Assumed NRC Project Mgt Responsibility for Cooper Nuclear Station ML20199E1521999-01-0707 January 1999 Forwards Insp Rept 50-298/98-22 on 981116-1208 & Notice of Violation Re Lack of Effective Oversight by Plant Mgt 1999-09-30
[Table view] |
Text
- - - _ _ _ . _ . ._ -_ . _ _ _ . . _ . . . _ . _.. __ _
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Doctet No.: 50-238 RB 1 $ 'SS6 ,
Mr. J. H. Pilant Technicel Staff Marager >
Nuclear Power Group i Nebrasta Public Fower Uf strict 1 P. O. Box 499 Columbus, Nebraska 68(41 '
SUBJECT:
5GIFIr.ATION OF VACWM BRERERS ON MARK I CCHTAINMENTS (CEhERIC LETTER 83-08)
Re; Cooper vclear 3tatfor, f By letter dated April 29, 75'83 you provided an evaluation of the ilof;per '
floclear Station Netwell-to-Urywelt Vacuum Breakers. A'e are continuing the review and find that we need the information re0sted in the escitsurc ;
to this letter in order to coinple.?,e our review regarding .the var.uum bwaken. t Please respond to this request within 45 days from receic a , of this letter. =
This request for infonnation was approved by the Cffice of Management and Budget under clearance W. 3150-0011. C m nts en buraan and duplicetion -
uay be directed to the Office of Maasknent and @dget. Reports Manager;>nt. _ .
Room 3208, !!ew Executive Office Buriding, Washincon,' O.C. 2050h
S$gtnaleign,3,g William O. Long, Project Manager DVR Project Directorate #2 Divk kn of 3% Licar.cin,o '
Enclosure:
DIS _TPED JTIO1(:- '
As stated T DBEW F 'TTaf ~ Gray File i flRC PDR Franklin Petearch Center cc w/ enclosure: Local POP l See next page (Dr.VoCon) i PDP2 P/F RBernero i
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' OFFICIAL RECORD COhY
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. l Mr. J. M. Pilent Nebraska Public Power District Cooper Nuclear Station
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Mr. G. D. Watson General Counsel Nebraska Public Power District P. O. Box 4999 Columbus, Nebraska 68601 Mr. Arthur C. Gehr, Attorney Snell & Wilmer 3100 Valley Certcr .
Phcenix, Arizona 85073 '
Cooper Nuclear Station ATTN: Mr. Paul Thomason. Division Panager of Nuclear Operations P. O. Box 98 Brownville, Nebraska 68321 Director Nebraska Departmer.t of Environmental Control P. O. Box 94877
. State House Station Linccin, Nebraska 68509 Mr. William Sittert, Commissioner Nemaha County Board of Commissioners Necaha County Ccurthouse Auburn, Nebraska 62205 Resident Inspector
- U.S. Nuclear Regulatory Commission P. O. Box 218 Brownville, Nebraska 68321 .
Regicnal Administrator Region IV U.S. Nuclear Regulatory Commission
, 611 Ryan Plare Drive, Suite 1000 Arlington, Texas 76011
- H. Ellis Simcons, Director L
Division of Radiological Health Department of Health 301 Centennial Mall, South P. O. Box 95307 Lincoln, Nebraska 63509
. _ . . ._ -- - - - -e - A
__ . _ .__ __ _ _ _ . . _ - . . . . _ _ _ _ _ _ . _ . . ~ . . _
V Reouest for Additional Information ,
Related to the tiodification of Vacuum Breakers on Mark 1 Containment ,
r f Cooper Nuclear Station- ,
I
- The results of the staff review of the Cooper Nuclear Station torus-to-drywell vacuum breaker evaluation identified several areas where further information is needed before the staff can comolete its review. These 2
areas sunnarized below were delineated in the staff's generic evaluation
- of the methodology prooosed to predict vacuun breaker valves opening and closino irpact velocities, letter from D. Vassallo to H, Pfefferlen,
] dateddecember 24, 2984 (copy attached).
I 1. Is the chugging source rate used in the evaluation the same as the one develooed in CDI Report (#E4-3)? If not the same, orovide the chuaning i source rate with the supporting justification. ;
- 2. Did the calculation aoply the 1.07 load factor to account for the uncertainty in calculating the underoressure (See Section IV of tha t
{ attachedevaluation).
j 3. Did the calculations use the drywell podel which results in the rest i conservative prediction (See Section V of the attached evaluation)?-
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'/ h n umT O STATES NUCLEAR RECULATORY COMMISSION I
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{ , was uwarow. o.c.neess
} % ,,,,. . December 24, 1984 i
i Mr. H. C. Pfefferlen, Manager BWR Licensing Procrams General Electric Company 175 Curtner Avenue, MC 682 San Jose, California 95125
Dear Mr. Pfefferlen:
SUBJECT:
EVALUATION OF MODEL FOR PREDICTING DRYWELL TO WETWELL VACUUM BREAKER VALVE DYNAMICS
. The staff issued Generic Letter 83-08 dated February 2, 1983, to all applicants and licensees of plants with Mark I containments reouesting .
)
submittal of information related to a potential failure mode of the !
{ .
drywell-to-torus vacuum breakers during the chugging and condensation 1 oscillation phases of a Loss-of-Coolant Accident (LOCA). As stated in the (
oeneric letter, this issue was discovered at the time the generic phase of l the Mark I Containment Long-Term Program was near ccepletion, however, the j
-, Mark I Owners Group connitted to resolve this issue although not necessarily as part of the NUREG-0661 Long Term Program. )
j
~
i To resolve the generic aspects of this issue the following reports were j prepared by Continuum Dynamics Inc. (CDI) for the General Electric Company ,
and the Mark I Owners Group: 1 CDI TECH NOTE B2-31, ' Mark 1 Vacuum Breaker Improved Dynamic Model - l Model Development and Validation" transmitted by your letter dated l October 28, 1982 '
~
CDI Report No. 84-3, ' Mark I Wetwell to Drywell Vacuum Breaker Load Methodology" transmitted by your letter dated March 2,1984 These reports describe the models to'be used to compute the vacuum breaker valve response to chugging' and condensation events in Mark I plants.
Based on our review of these reports and the additional information provided in your letters dated September 26,1984 and November 6, 1984, we haya concluded that the valve dynamic model conservatively predicts the opening and closing velocities for the valve and, therefore, is acceptable for use in the analyses and/or qualiffcation of Mark I wetwell-to-drywell
9 Mr. H. C. Pfefferlen - 2-vacuumireaker valves subject to the restrictions set forth in Section V of the enclosed Safety Evaluation (SE).
SinEarely, nic 8. Vassallo, Chief Operating Reactors Branch #2 Division of Licensing
Enclosure:
As stated i
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3AFETY FVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION ON THE ACCEPTABilf 7Y OF THE ANALYTICAL MODEL 00R PREDICTING VALVE OYNAMICS l
i
- 1. Introduction :
I i
Mark I containments are equipped with simple check valves to serve as vacuum breakers to equalize any overpressure of the wetwell air space region relative to the drywell so that the reverse direction differential pressure will not
- exceed the design value. In general, the vacuum breakers will swing open when the wetwell eir space pressure is 0.5 psi (or more) greater than the vent. header pressure. Typical vacuum breaker arrangements for the Mark I plants are shown in i
~
Figure 1. As shown, internal vacuum breakers are located on the vent pipes, E and external vacuum breakers are located in a supplementary piping system.
- Following the onset of a loss-of-coolant accident (LOCA) and during the chugging phase, caused by the rapid condensation of the steam at the vent exit, the vacuura breaker may be called upon to function in a cyclic manner. This is due t3 the fact that the chugging phenomenon is repeate'd on the average every two seconds causing strong dynamic underpressure conditions in the vent pipe, which depending on the chug strength may open the vacuum breaker with high velocity. The underpressure condition which normally lasts for about 5 msec is followed by a dynamic overpressure condition, which again depending on the strength of the chug, may close the vacuum breaker with high velocity. l Failure of a vacuum breaker to reclose could result in a pathway for steam bypass of the pool, thus , jeopardizing the ' integrity of the coritainment.
II. Backgr6und
- During the Mark I Full Scale Test Facility (FSTF) containment loads program, a GPE wetwell to drywell vacuum breaker was observed to cycle. Inspection of the valve after Test MI, which had the highest opening velocity, revealed that ,
the pallet hinge was bent, the latching magnet was broken and indentation was 4
observed in the valve casing which suggested that the pallet opened fully during the test. In other tests, there also was observed damage but it was licited to i ((' the pallet sealing gasket. MI was the only test in the FSTF test series which i
had fully opened the vacuum breaker. Having presented the test results it she'uld be noted that the actuation velocities sustained in the FSTF test program are not considered to be prototypical. The results are considered very conservative
/ because the drywell volume in ths FSTF is much smaller than any domestic l- Mark I plant. For this reason, it was concluded in CDI report #84-3, that opening impacts and hence the vacuum breaker damage observed in test MI, are not anticipated in domestic Mark I plants.
~
j III. Summary of the Topical Reports Report CDI #82-31 describes the methodology used to predict the drywell to wetwell vacuum breaker cycling velocities, particularly when and if the valve i disk strikes the full open stop or seat. Since the location of vacuum l breakers vary from plant to plant, a need exists to quantify the ring header /wetwell pressare fluctuations for plant unique application.$ CDI report
- 84-3 describes an analytical model to extract condensation source time l
. 1 l
_ . _ _ . _ - _ - . - _ - _ - _ - _ _ _ . _ _ - ~ _ . ---
- 3-histories ffom the FSTF test f acility. After transferring these condensation sources to a model of an actual Mark I plant, the analytical model would compute the pressure time history across the' disk of the vasvum breaker.
Figure 2, extracted from CDI report 84-3, provides the steps followed to i detemine the plant unique vacuum breaker forcing functions.
111.1 Valve Dynamic Model Verifiestio3 7 The dynamics of the vacuum breeker, described in COI report 82-31, is simulated in tenns of the hydrodynamic torque about the valve shaft. This torque is as a consequence of a differential pressure across the valve disk.
g., During run tS-DA of the F5TF tests, the vacuum breaker was !nstrumented such a
that the valve displacement and pressure differential across the valve disk were recorded. This information was used to verify the valve dynamic model as i .
l follows. By driving tne valve dynamic model with the seasu.*ed differential pressure across the valve from test f5-DA, predictions of valve displacement versus time were made and compared against the measured data from the same FSTF run #5-DA. 1 l
't The results of this comparison indicated that the predicted impact velocities i
were greater than the experimental values by an average factor of more than
- 21. This extreme conservatism was attributed to the fact that the valve l dynamic model did not account for the reduction 'in the hydrodynamic torque as l a result of the reduced static pressure across the valve disk due to l flow computations. A parametric study was perfomed to reduce this 4
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conservatism. The result was the development of a conservative yet realistic valve dynamic model described in CDI report #82-31. Comparison of the predicted valve impact velocities based on the improved model still bounded all test impact velocities with approximately a 12% margin.
It was, therefore, concluded in the CDI report #82-31 that the valve dynamic model is appropriate for the analysis and/or qualification of Mark I wetwell to drywell vacuum breaker.
III.2 Vent Dynamic Model Verification r, The model descri. bed in CDI report #84-3 was developed to allow the development b #
4-of unsteady condensation rate at the vent exit from the reasured FSTF drywell pressure. A transfer function was developed which translates the condensation soprce at the vent exit to a pressure at any location in the vent system.
, The pressure time history measured in the drywell was used with the transfer function to deduce the condensation rate at the vent exit. This source was then used with the transfer function to predict the unsteady pressure at a location in the vent header where measurements were taken. The comparisons
_ between the measured and predicted pressures were favorable and, therefore, it was concluded that the transfer function model contains the essential elements ;
required to predict pressure oscillations in Mark I steam vent systims. Since !
.. l the condensation rate is fixed by local conditions at the vent exit, i.e.,
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l 5-5 steam mass flow rate, noncondensibles and thermodynamic conditions, these conditions would only vary slightly between plants and, therefore, the 4
condensation rate / source thus developed can be used in any Mark I facility to predict the unsteady pressure at the prescribed location of the vacuum breaker.
III.3 Selection of the Condensation Source The FSTF test data were screened to determine the chugging events that produced the most severe actuation of the vacuum breaker, i.e., large impact velocities. Over 1000 seconds of chugging data were recorded in which 400 distinct chug events actuated the vacuum breaker 179 times. Three runs were
{5 noted to have significant chugging: runs MI, M4 and M9. Data from these runs
. were used to drive the vacuum breaker valve described in Section III.1 to
, detemine the maximum impacts of the valve disk on the body and the seat of the valve. It was determined by CDI that the time interval 65.9-105.9 seconds of run MI would bound all FSTF data including those that caused the valve damage in test M1; therefore, the 65.9 to 105.9 seconds time interval was chosen to determine the condensation rate as described in Section 111.2 IV. Plant Unique Application The transfer function discussed in Section III.2 is modified for plant unique l 3 application by inputting the 1) drywell volume / total vent area, 2) ~ pool submergence and 3) damping due to external piping length (for the six .'tark I plants that have external va uum breakers). The condensation rate discussed
- s. .
. i in Section 111.3 is used with the plant unique modified transfer function to compute the pressure on the vent side of the vacuum breaker disk and the wetwell air space pressure. A ' sensitivity study of the vent dynamic model demonstrated that the wetwell air space pressure is insensitive to the wetwell air space volume. (Pool pressure coefficient in response to question 4 1
represents the wetwell air space volume in the sensitivity study). Therefore, this volume is not considered as a plant unique input in the model.
These two pressures are then subtracted, multiplied by a load factor of 1.07 (to account for uncertainty in calculeting the underpressure) and applied across the vacuum breaker valve dynamic model discussed in Section 111.1 to obtain disk actuation velocities.
_ V. Staff's Evaluation and Recomendation During the review of the infomation presented in the CDI reports, the staff '
expressed concern on weather the damage sustained to the valve installed on the
~
FSTF could occur in domestic Mark I plants. The' staff also expressed concern that using the methodology, no opening impacts were anticipated in
- Mark I plants even though the valve that was installed on the FSTF had an opening impact during test M1.
In response to these concerns, CDI stated that the vacuum breaker response in the FSTF was not prototypical and is very conservative. This is due to the fact that the drywell volume / total vent area ratio in the FSTF is asch smaller
- than any domestic Mark I plant. CDI contends that this ratio has a significant e
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influence on the pressure oscillation in the ring header and in turn,,an '
influence on the load across the vacuum breaker. To illustrate this point, CDI provided the results of analyses which sho.ed that the vent pressure monotonically decreases with increasing drywell volume / vent area ratio. The calculated load across the vacuum breaker would also decrease as this ratio increased. Based .
on the above, CDI concluded that the large opening impact velocities and valve damage experienced during the FSTF test M1 are unlikely to occur in any domestic Mark I plant.
4 Based on our review of the methods and assumptions described in the CDI reports, and the response to the request for additional infonnation (RAI),
we conclude that the valve dynamic model conservatively predicts valve opening .
and closing velocities and, therefore, is acceptable for use in the analysis and/or qualification of Mark I wetwell to drywell vacuum breakers subject to the following restrictions:
~
- 1. The plant unique loads 'are to be computed using one of two drywell models which result in the most conserfative prediction. One model examined by
. CDI represents the drywell by a capacitance in the vent dynamic model as i
discuss 6* in Section 111.2. The other model divides the drywell into two i
cylinders; treating each volume as an acoustic circuit in the vent dynamic model; I ..
i I
, - - - - - _ _.- _ _ _ , . _ . _ . ~ . _ _ . _ . _ . _ , _ _ . _ _ _ _ . . _ , _ _ . _ . _ . _ . . , . . . _ . . - . - - . -
. 8- ,
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- 2. The salue of all plant unique parameters inputted to the models to obtain plant' Jnique wetwell to drywell vacuum breaker load definitions should be provided with the results; and
- 3. Any plant-unique deviations of the methodology and/or assumptions that were found acceptable in this report should be identified. Additionally, the rationale and justification for the proposed alternative method and/or assumptions should be provided. Justification should include the
_ identificationoftheconservatismassociatedwiththedeviation.
Principal Contributor: F. E1tawila Dated: December 24, 1984 (I, -
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REFERENCES 1s CDI TECH NOTE 82-31. " Mark I Vacuum Breaker Improved Dynamic Model -
Model_ Development and Validation."
- 2. CDI Report No. 84-3 " Mark I Wetwell to Drywell Vacuum Breaker Load Methodology,."
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STIP Develop a dynamic model of the
- vent system, stes= water inter-1 face and peal slosh with the condensation rate at the int.er-face unknoun.
- q ,
Vse measured drywell pressure to 2 determine the condensation rate. -
! i f I
F- With the condensation rate i J deter =ined,~~ predict unsteady k 3 pressures at other vant locations
.- to validate the model.
y Use the condensation source at the vent exit to drive dyna =ic 4 models of Mark I plants to determine unique vacuum breaker forcing functions.-
1 Tigure 2 steps in determining plant unique vacuum breaker forcing functions l
.,- ,. ,- -