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Category:CORRESPONDENCE-LETTERS
MONTHYEARML20217K3161999-10-19019 October 1999 Forwards Amend 195 to License DPR-61 & Safety Evaluation. Amend Deletes Certain TSs Either No Longer Applicable to Permanently Shutdown & Defueled State of Reactor or Duplicate Regulatory Requirements CY-99-137, Notifies NRC of Intent to Apply Haddam Neck Plant 10CFR50 App B,Qa Program to Activities Related to Development of ISFSI at Haddam1999-10-12012 October 1999 Notifies NRC of Intent to Apply Haddam Neck Plant 10CFR50 App B,Qa Program to Activities Related to Development of ISFSI at Haddam DD-99-11, Informs That Time Provided by NRC Regulation within Which Commission May Act to Review Director'S Decision (DD-99-11) Expired & That Commission Declined Any Review.Decision Became Final Action on 9910041999-10-0808 October 1999 Informs That Time Provided by NRC Regulation within Which Commission May Act to Review Director'S Decision (DD-99-11) Expired & That Commission Declined Any Review.Decision Became Final Action on 991004 ML20212L1261999-10-0404 October 1999 Forwards Viewgraphs Presented by Licensee at 990923 Meeting with Nrc,In Response to Request ML20212D0341999-09-20020 September 1999 Expresses Appreciation for Accepting NRC Request for Tour of Haddam Neck Facility During on 991014.Invites R Mellor to Participate in NRC 1999 Decommissioninng Power Reactor Work- Shop:Nrc Insp Program at Decommissioning Power Reactors CY-99-111, Submits Clarification of Changes Made to Connecticut Yankee QA Program,Per Util 990810 Submittal.Change Will Be Submitted to NRC in Dec 1999 as Part of Annual Update1999-09-0202 September 1999 Submits Clarification of Changes Made to Connecticut Yankee QA Program,Per Util 990810 Submittal.Change Will Be Submitted to NRC in Dec 1999 as Part of Annual Update ML20211E8051999-08-20020 August 1999 Forwards Insp Rept 50-213/99-02 on 990420-0719.No Violations Noted.Completion of Corrective Actions for Spent Fuel Bldg Ventilation Issues Adequate ML20210J6021999-08-0202 August 1999 Informs That Info Re Orise Technical Survey Assistance to NRC at CT Yankee Is to Include Copies of Listed Documents CY-99-048, Forwards Cyap Rept CY-HP-0031,Rev 0, Bounding Dose Assessment for Offsite Radioactive Matls1999-07-29029 July 1999 Forwards Cyap Rept CY-HP-0031,Rev 0, Bounding Dose Assessment for Offsite Radioactive Matls CY-99-066, Forwards Revised Plan for Recovery of Licensed Matl from Offsite Locations.Completion of Implementation of Plan During Summer of 1999 Is Planned,Contingent on Support Extended by Property Owners,Weather & Uncontrolled Factors1999-07-20020 July 1999 Forwards Revised Plan for Recovery of Licensed Matl from Offsite Locations.Completion of Implementation of Plan During Summer of 1999 Is Planned,Contingent on Support Extended by Property Owners,Weather & Uncontrolled Factors ML20210C1491999-07-0101 July 1999 Responds to ,Which Responded to NRC Ltr & NOV & Informs That Engagement in Any Similar Wrongdoing in Future May Result in More Significant Enforcement Action. No Further Action Will Be Taken at This Time ML20209C3911999-06-30030 June 1999 Forwards TS Page 6-3 for Haddam Neck Plant ML20195H1741999-06-15015 June 1999 Forwards Original & Copy of Request for Approval of Certain Indirect & Direct Transfer of License & Ownership Interests of Montaup Electric Co (Montaup) with Respect to Nuclear Facilities Described as Listed ML20195F9011999-06-0909 June 1999 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp 50-213/98-06 on 990226. Util Did Not Agree with Disposition of Issue Cited as Severity Level IV Violation.Violation Will Be Noncited ML20195H3591999-06-0202 June 1999 Responds to NRC Re Violations Noted in Insp of License DPR-61.Corrective Actions:Disciplinary Actions Were Taken by Util Against Jm Foley & Individual & Departmental Emphasis Is Placed on New HP Stds & Expectations ML20207E9031999-06-0202 June 1999 Informs That NRC Office of Nuclear Reactor Regulation Reorganized Effective 990328.As Part of Reorganization,Div of Licensing Project Mgt Created.Mt Masnik Will Be Section Chief for Haddam Neck.Organization Chart Encl ML20207B9301999-05-25025 May 1999 Responds to 990114 Correspondence Re Changes to Plant Defueled Physical Security Plan Rev 1 Submitted Under 10CFR50.54(p).Implementation of Changes Subj to Insp to Confirm Changes Have Not Decreased Security Plan ML20207G1761999-05-21021 May 1999 Forwards Insp Rept 50-213/99-01 on 980119-990419 & Closure of CAL 1-97-010.No Violations Noted.Conduct of Activities Associated with Control of Radiological Work at Haddam Neck Generally Characterized as Careful & Thorough ML20206R7221999-05-12012 May 1999 Refers to Investigation 1-97-031 on 970616-0718 & Forwards Nov.Investigation Found That Recipient Deliberately Did Not Follow Radiation Protection Procedures,Falsified Documents & Provided Incomplete & Inaccurate Info to NRC ML20206R8051999-05-12012 May 1999 Responds to 3 Investigations,Repts 1-97-031,008 & 1-98-008 Between 970314 & 980722 as Well as Insp Conducted Between 980720 & 1102.Forwards Synopsis of 3rd OI Investigation ML20206R7021999-05-12012 May 1999 Refers to Investigation 1-97-008 Conducted by Region I & Forwards Notice of Violation.Investigation Found That Recipient Deliberately Attempted to Conceal Release of Contaminated Video Equipment ML20206J2801999-04-30030 April 1999 Forwards 1998 Annual Financial Repts for CT Light & Power Co,Western Ma Electric Co,Public Svc Co of Nh,North Atlantic Energy Corp,Northeast Nuclear Energy Co & North Atlantic Energy Svc Corp,License Holders CY-99-057, Forwards 1998 Annual Radioactive Effluent Rept for HNP, & Rev 10 to Remodcm. with Summary of Quantities of Solid Radwaste & Liquid & Gaseous Effluents,As Well as Summary of Assessment of Max Individual Dose1999-04-30030 April 1999 Forwards 1998 Annual Radioactive Effluent Rept for HNP, & Rev 10 to Remodcm. with Summary of Quantities of Solid Radwaste & Liquid & Gaseous Effluents,As Well as Summary of Assessment of Max Individual Dose ML20206C8631999-04-28028 April 1999 Forwards Amend 194 to License DPR-61 & Safety Evaluation. Amend Authorizes Relocation of Requirements Related to Seismic Monitoring Instrumentation from TSs to Technical Requirements Manual ML20206A6871999-04-22022 April 1999 Informs of Completion of Review of Re Nepco in Capacity as Minority Shareholder in Vermont Yankee Nuclear Power Corp,Yaec,Myap & Connecticut Yankee Atomic Power Co ML20210V5221999-04-0808 April 1999 Discusses Continued Performance of Technical Assistance Activities for NRC & Environ Survey & Site Assessment Program (Essap) Survey Assistance at Cy IR 05000213/19960121999-04-0505 April 1999 Discusses NRC Insp Repts 50-213/96-12 & 50-213/98-04 on 961102-27 Re Airborne Radioactivity Contamination Event That Occurred in Fuel Transfer Canal & Reactor Cavity in Nov 1996.Notice of Violation Encl ML20205J7931999-04-0505 April 1999 Discusses NRC Insp Repts 50-213/96-12 & 50-213/98-04 on 961102-27 Re Airborne Radioactivity Contamination Event That Occurred in Fuel Transfer Canal & Reactor Cavity in Nov 1996.Notice of Violation Encl CY-99-042, Provides Info on Status of Decommissioning Funding for Haddam Neck Plant1999-03-31031 March 1999 Provides Info on Status of Decommissioning Funding for Haddam Neck Plant CY-99-024, Responds to Violations Noted in Insp Rept 50-213/98-06. Corrective Actions:Meetings Were Held with Contractor Mgt, Disciplinary Action Against Worker Was Taken & Notices Alerting Workers to HRA Controls Were Posted1999-03-29029 March 1999 Responds to Violations Noted in Insp Rept 50-213/98-06. Corrective Actions:Meetings Were Held with Contractor Mgt, Disciplinary Action Against Worker Was Taken & Notices Alerting Workers to HRA Controls Were Posted ML20206A6951999-03-29029 March 1999 Request Confirmation That No NRC Action or Approval,Required Relative to Proposed Change in Upstream Economic Ownership of New England Power Co,Minority Shareholder in Vermont Yankee Nuclear Power Corp,Yaec,Myap & Connecticut Yankee B17697, Notifies NRC of Amount of Property Insurance Coverage, Effective 990401,for HNP & Mnps,Units 1,2 & 3,per Provisions of 10CFR50.54(w)1999-03-12012 March 1999 Notifies NRC of Amount of Property Insurance Coverage, Effective 990401,for HNP & Mnps,Units 1,2 & 3,per Provisions of 10CFR50.54(w) CY-99-032, Clarifies Info Re TRM Change Submitted with Re Proposed Rev to TSs on Seismic Monitoring1999-03-0909 March 1999 Clarifies Info Re TRM Change Submitted with Re Proposed Rev to TSs on Seismic Monitoring ML20207B6641999-02-26026 February 1999 Forwards Insp Rept 50-213/98-06 on 981103-990118 & Notice of Violation Re Locked High Radiation Area Doors That Were Found Unlocked by Staff.Security Program Was Also Inspected ML20204C6901999-02-22022 February 1999 Informs That Public Citizen Waives Copyright for 5th Edition of Nuclear Lemon So NRC May Reproduce for Purpose of Contributing to NRC Recommended Improvements to Oversight Process for Nuclear Power Reactors ML20203H9621999-02-17017 February 1999 Responds to to Dk Rathbun Which Forwarded Number of Questions from Constituent Re Spent Fuel Decommissioned Nuclear plants.NUREG-1628, Staff Responses to Frequently Asked Questions Re Decommissioning of NPPs Encl.W/O Encl CY-99-005, Responds to NRC 981221 RAI Re Amend 193 to License to Reflect Permanent Shutdown Condition of Plant.Licensee Withdrawing 981030 (CY-98-199) Request & Will Submit Corrections in Future Proposed Rev to TS1999-01-29029 January 1999 Responds to NRC 981221 RAI Re Amend 193 to License to Reflect Permanent Shutdown Condition of Plant.Licensee Withdrawing 981030 (CY-98-199) Request & Will Submit Corrections in Future Proposed Rev to TS CY-99-023, Provides Summary of Understandings Reached During 990108 Meeting Between Util & CT Dept of Environ Protection Re Dike Area Rainwater Reporting Protocol1999-01-28028 January 1999 Provides Summary of Understandings Reached During 990108 Meeting Between Util & CT Dept of Environ Protection Re Dike Area Rainwater Reporting Protocol ML20203H9711999-01-21021 January 1999 Requests Response to Concerns Raised by Constitutent M Marucci Re Spent Fuel at Decommissioned Nuclear Plants CY-99-002, Forwards Response to NRC 981203 RAI Re Proposed License Amend to Relocate Requirements for Seismic Monitoring Instrumentation from Section 3/4.3.3.3 of TS to Trm. Supporting TSs Encl1999-01-18018 January 1999 Forwards Response to NRC 981203 RAI Re Proposed License Amend to Relocate Requirements for Seismic Monitoring Instrumentation from Section 3/4.3.3.3 of TS to Trm. Supporting TSs Encl CY-99-010, Provides Special Rept Concerning Potential of Radiation Exposure Due to Hypothetical Explosive Attack to Facility. Without Encl1999-01-14014 January 1999 Provides Special Rept Concerning Potential of Radiation Exposure Due to Hypothetical Explosive Attack to Facility. Without Encl CY-99-009, Forwards Rev 1 to Haddam Neck Plant Defueled Physical Security Plan,Per 10CFR50.54(p).Rev Does Not Decrease Effectiveness of Plan.Encl Withheld,Per 10CFR73.21 & 2.7901999-01-14014 January 1999 Forwards Rev 1 to Haddam Neck Plant Defueled Physical Security Plan,Per 10CFR50.54(p).Rev Does Not Decrease Effectiveness of Plan.Encl Withheld,Per 10CFR73.21 & 2.790 ML20206R6051999-01-11011 January 1999 Ack Receipt of Submiting Sf Mgt Plan.Staff Has Reviewed Plan & Notes Plan to Store Sf in SFP Until DOE Takes Physical Possession of Fuel DD-98-12, Informs That Time Provided by NRC Regulation within Which Commission May Act to Review Director'S Decision DD-98-12 Has Expired.Decision Became Final Agency Action on 981211. with Certificate of Svc.Served on 9812221998-12-22022 December 1998 Informs That Time Provided by NRC Regulation within Which Commission May Act to Review Director'S Decision DD-98-12 Has Expired.Decision Became Final Agency Action on 981211. with Certificate of Svc.Served on 981222 CY-98-142, Forwards Proposed Rev 2 of Cyap QAP for Info & Approval of Exception Number 8 of App E of Cy Qap.Copy of Rev 2 Showing Changes from Rev 1 Also Included1998-12-22022 December 1998 Forwards Proposed Rev 2 of Cyap QAP for Info & Approval of Exception Number 8 of App E of Cy Qap.Copy of Rev 2 Showing Changes from Rev 1 Also Included ML20198R1321998-12-21021 December 1998 Forwards Insp Rept 50-213/98-05 on 980720-1102.No Violations Noted.Insp Completes Review of Licensee Actions Described in ,In Response to NOV & Proposed Imposition of Civil Penalties ML20198K8651998-12-21021 December 1998 Ack Receipt of ,Requesting Corrected Pages to Be Issued for License Amend 193,issued on 980630.Informs That Inconsistencies Found When Comparing Corrected Pages Submitted on 981030 & License Amend Application CY-98-201, Provides Clarification of NRC Staff SE for Amend 193 Which Approved HNP Defueled TSs1998-12-0303 December 1998 Provides Clarification of NRC Staff SE for Amend 193 Which Approved HNP Defueled TSs IR 05000213/19980041998-11-27027 November 1998 Forwards Special Insp Rept 50-213/98-04 of Licensee Performance During Reactor Coolant Sys Chemical Decontamination ML20195J3571998-11-19019 November 1998 Forwards Exemption from Certain Requirements of 10CFR50.54(w) & 10CFR140.Exemption Submitted in Response to 971007 Application & Suppls & 1218,requesting Reduction in Amount of Insurance Required for Facility 1999-09-20
[Table view] Category:NRC TO UTILITY
MONTHYEARML20062F4991990-11-16016 November 1990 Forwards List of Unimplemented GSIs at Facilities,Per Generic Ltr 90-04.Timely Completion Requested ML20217A2021990-11-0909 November 1990 Forwards Insp Repts 50-213/90-83,50-245/90-82 & 50-336/90-82 & 50-423/90-83 on 900924-28.No Violations Noted ML20062D7701990-11-0606 November 1990 Lists Resolved SEP Issues & Corresponding Sections of Tech Specs as Result of STS Upgrade Amend ML20058H3961990-10-30030 October 1990 Advises of Acceptance of Revs 19,20 & 21 to Physical Security Plan,Per 891005 & 17 & s ML20058D5601990-10-24024 October 1990 Forwards Team Insps 50-213/90-82,50-245/90-81,50-336/90-81 & 50-423/90-82 on 901001-12 ML20062B7321990-10-22022 October 1990 Forwards Amend 132 to License DPR-61 & Safety Evaluation. Amend Adds Footnote to Tech Spec Table 3.3-2 Item 3,Table 3.3-3,Item 2 & Table 4.3-2,Item 3 ML20058A6331990-10-19019 October 1990 Forwards Safety Insp Rept 50-213/90-13 on 900801-0911.Strong Performance Noted in Actions to Resolve Failure of SG Feedwater Regulating Valve on 900807 & 0911 ML20062B7141990-10-12012 October 1990 Extends Invitation to Attend 910220-21 Util Symposium/ Workshop in King of Prussia,Pa on Engineering Role in Plant Support ML20062B3321990-10-10010 October 1990 Forwards Insp Rept 50-213/90-18 on 900926.Violations Noted. Enforcement Conference Scheduled for 901019 ML20059H2981990-09-0606 September 1990 Forwards Revised Safety Evaluation for Amend 127 to License DPR-61.Revised Evaluation Further Clarifies Individual Rod Position Indication Testing Exception & Bases for Approval ML20059D1691990-08-30030 August 1990 Grants NRR Temporary Waiver of Compliance Re Steam turbine- Driven Auxiliary Feedwater Pumps Based on 900824 & 29 Requests ML20059E6621990-08-28028 August 1990 Forwards Safety Insp Rept 50-213/90-12 on 900621-0731. Good Mgt Attention Given to Correction of Deficiencies Identified During Process & Verification That Tech Spec & Procedural Requirements Met Prior to Plant Heatup ML20059A7901990-08-14014 August 1990 Forwards Sser Accepting Electrical Design of New Switchgear Room at Plant ML20058N0601990-08-0606 August 1990 Discusses Licensee Engineering Initiatives.Util Encouraged to Begin Similar Initiative.Cooperative Effort Would Promote Efficiency & Enhance Effectiveness of Nuclear Power Plant Engineering Activities ML20058M5361990-08-0606 August 1990 Forwards Review of Westinghouse Rept WCAP-12277, Westinghouse Owners Group Bounding Evaluation for Pressurizer Surge Line Thermal Stratification, Per NRC Bulletin 88-011 ML20056A7831990-08-0303 August 1990 Forwards Notice of Consideration of Issuance of Amend to License DPR-61 & Proposed NSHC Determination & Opportunity for Hearing.Amend Would Reword Tech Specs Section 3.4.6.2.f to Better Define Sections of Piping ML20056A5671990-08-0303 August 1990 Forwards Notice of Consideration of Issuance of Amend to License DPR-61 Re 900726 Request to Add Exception from Requirements of Tech Spec 4.0.4 to Surveillance Requirements 4.7.1.2.2a,b & C for Entry Into Mode 3 ML20056A5621990-08-0303 August 1990 Forwards Safety Evaluation Re Cracks & Flaw Indications in Plant Pressurizer ML20056A1771990-07-27027 July 1990 Proposes to Review 900726 Tech Spec Request for NRR Temporary Waiver of Compliance Re Steam turbine-driven Auxiliary Feedwater Pumps.Waiver Will Allow Plant to Proceed to Mode 3 W/O First Demonstrating Sys Operability ML20056A3411990-07-26026 July 1990 Formalizes Requests Made in 900724 Conversation Between D Ray & J Prell Re 901009-1017 Planned Insp of Eop.List of Ref Matl to Be Provided Before 900818 & Tentative Schedule for Insp Period,Including Required Facility Support Encl ML20055G5741990-07-19019 July 1990 Forwards Request for Addl Info Re NRC Bulletin 88-002, Rapidly Propagating Fatigue Cracks in Steam Generator Tubes. Info Needed to Complete Safety Evaluation ML20055G5381990-07-19019 July 1990 Forwards Amend 128 to License DPR-61,safety Evaluation & Notice of Issuance of Amend to License.Amend Revises Tech Specs to Reflect Removal of Thermal Shield & Attached Surveillance Capsules ML20055G5531990-07-19019 July 1990 Forwards Amend 129 to License DPR-61 & Safety Evaluation. Amend Adds Footnote to Tech Spec Section 5.3.1, Fuel Assemblies to Allow Operation of Cycles 16 & 17 W/Two Solid Type 304 Stainless Steel Filler Rods in Place of Fuel Rods ML20055F7291990-07-13013 July 1990 Forwards Environ Assessment & Finding of No Significant Impact Re 900509 Application for Amend to Tech Spec 5.3.1, Fuel Assemblies ML20055F7221990-07-12012 July 1990 Forwards Notice of Consideration of Issuance of Amend to License DPR-61,per 900625 Application ML20055G1101990-07-12012 July 1990 Forwards Safety Insp Rept 50-213/90-08 on 900509-0620 ML20055F7371990-07-11011 July 1990 Reviews 891227 Response to Generic Ltr 89-10 Re safety- Related motor-operated Valve Testing & Surveillance. Justification Should Be Provided If Initial Testing Program Cannot Be Completed within 5 Yrs or Three Refueling Outages ML20055F6061990-07-0909 July 1990 Forwards Final SALP Rept 50-213/88-99 for 880801-900215. Evaluation of 900619 SALP Comments Resulted in No Changes to SALP Ratings & SALP Rept Not Modified ML20055E2311990-07-0202 July 1990 Forwards Amend 126 to License DPR-61 & Safety Evaluation. Amend Revises Tech Specs to Reflect Mods Performed on Fire Protection Sys.Changes Include Increasing Operable Smoke & Heat Detectors Required in Diesel Generator Rooms a & B ML20055F5521990-06-29029 June 1990 Forwards Radiation Safety Insp Rept 50-213/90-11 on 900604- 08.No Violations Noted ML20059M9001990-06-13013 June 1990 Forwards NRC Performance Indicators for First Quarter 1990. W/O Encl ML20055C6011990-05-18018 May 1990 Forwards Safety Insp Rept 50-213/90-07 on 900402-05.No Violations Noted ML20248G1471989-09-29029 September 1989 Forwards Insp Rept 50-213/89-12 on 890726-0905.No Violations Noted ML20248G7111989-09-25025 September 1989 Forwards Safety Insp Rept 50-213/89-14 on 890911-15.No Violations or Deviations Noted ML20248D2271989-09-20020 September 1989 Forwards Amend 15 to Indemnity Agreement B-32,reflecting Changes to 10CFR140.Amend Reflects Increase from Primary Layer of Nuclear Energy Liability Insurance & Also Conforms to Changes Made to Price-Anderson Amend Act of 1988 ML20247N2871989-09-18018 September 1989 Forwards Safety Insp Rept 50-213/89-13 on 890814-18.No Violations Noted ML20247K2231989-09-11011 September 1989 Forwards Amends 123 & 41 to Licenses DPR-61 & NPF-49, Respectively & Safety Evaluation.Amends Change Tech Specs 4.10.1.D.1.h & 4.4.5.4.a.8 to Allow Insp of Steam Generator Tubes by Insertion of Ultrasonic Test Probe ML20247E3371989-09-0707 September 1989 Forwards Amends 122,34,143 & 40 to Licenses DPR-61,DPR-21, DPR-65 & NPF-49,respectively & Safety Evaluation.Amends Change Tech Spec Sections 6.10.2.m & 6.10.3 Re Records Retention for Radiological Effluent Monitoring & ODCM ML20247A4471989-09-0505 September 1989 Forwards Amend 121 to License DPR-61 & Safety Evaluation. Amend Revises & Combines Tech Spec Sections 3.6,3.7 & 4.3 Into New Section 3.6, Eccs ML20247A1601989-08-31031 August 1989 Forwards Notice of Consideration of Issuance of Amend to License DPR-61,upgrading Current Custom Tech Spec Format to Westinghouse STS Format ML20246P4541989-08-31031 August 1989 Forwards Notice of Consideration of Issuance of Amend to License DPR-61.Amend Will Revise Tech Specs to Reflect Changes Associated W/Plant Fire Detection/Suppression Sys Upgrades in Support of New Switchgear Bldg ML20247F4581989-08-30030 August 1989 Forwards Safety Insp Rept 50-213/89-11 on 890731-0804.No Violations Noted ML20246P4291989-08-29029 August 1989 Forwards Notice of Consideration of Issuance of Amend to License DPR-61 & Opportunity for Hearing.Amend Revises Tech Specs to Reflect Mods to Upgrade Reactor Protection Sys & Nuclear Instrumentation Sys ML20246K0451989-08-28028 August 1989 Forwards Requalification Program Evaluation Rept 50-213/89-06OL of Exams Administered on 890501-05.Evaluation Conducted Per Rev 5 to NUREG-1021,Operator Licensing Examiner Std,ES-601, Administration of Nrc.. ML20246F3901989-08-18018 August 1989 Forwards Insp Rept 50-213/89-10 on 890614-0725 ML20245H9651989-08-14014 August 1989 Forwards Exemption Permitting one-time Extension of Test Period for Type a Test from 870927,or Later,Until Next Refueling Outage (RO) & for Type B & C Tests from 870718 or Later,Until Next Ro.Safety Evaluation Also Encl ML20246C8211989-08-11011 August 1989 Confirms 890808 Telcon Re Util Participation in NRC Regulatory Impact Survey on 891023 in Berlin,Ct.Schedule & General Discussion Groups Shown in Encl ML20245F4981989-08-0404 August 1989 Forwards Safeguards Insp Rept 50-213/89-09 on 890626-30.No Violations Noted ML20247E6451989-07-20020 July 1989 Forwards Amend 120 to License DPR-61 & Safety Evaluation. Amend Changes Tech Specs 3.17.1, Axial Offset & 3.17.2, LHGR to Allow Coastdown Operation of Plant at End of Cycle 15 1990-09-06
[Table view] Category:OUTGOING CORRESPONDENCE
MONTHYEARML20217K3161999-10-19019 October 1999 Forwards Amend 195 to License DPR-61 & Safety Evaluation. Amend Deletes Certain TSs Either No Longer Applicable to Permanently Shutdown & Defueled State of Reactor or Duplicate Regulatory Requirements DD-99-11, Informs That Time Provided by NRC Regulation within Which Commission May Act to Review Director'S Decision (DD-99-11) Expired & That Commission Declined Any Review.Decision Became Final Action on 9910041999-10-0808 October 1999 Informs That Time Provided by NRC Regulation within Which Commission May Act to Review Director'S Decision (DD-99-11) Expired & That Commission Declined Any Review.Decision Became Final Action on 991004 ML20212L1261999-10-0404 October 1999 Forwards Viewgraphs Presented by Licensee at 990923 Meeting with Nrc,In Response to Request ML20212D0341999-09-20020 September 1999 Expresses Appreciation for Accepting NRC Request for Tour of Haddam Neck Facility During on 991014.Invites R Mellor to Participate in NRC 1999 Decommissioninng Power Reactor Work- Shop:Nrc Insp Program at Decommissioning Power Reactors ML20211E8051999-08-20020 August 1999 Forwards Insp Rept 50-213/99-02 on 990420-0719.No Violations Noted.Completion of Corrective Actions for Spent Fuel Bldg Ventilation Issues Adequate ML20210J6021999-08-0202 August 1999 Informs That Info Re Orise Technical Survey Assistance to NRC at CT Yankee Is to Include Copies of Listed Documents ML20210C1491999-07-0101 July 1999 Responds to ,Which Responded to NRC Ltr & NOV & Informs That Engagement in Any Similar Wrongdoing in Future May Result in More Significant Enforcement Action. No Further Action Will Be Taken at This Time ML20195F9011999-06-0909 June 1999 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp 50-213/98-06 on 990226. Util Did Not Agree with Disposition of Issue Cited as Severity Level IV Violation.Violation Will Be Noncited ML20207E9031999-06-0202 June 1999 Informs That NRC Office of Nuclear Reactor Regulation Reorganized Effective 990328.As Part of Reorganization,Div of Licensing Project Mgt Created.Mt Masnik Will Be Section Chief for Haddam Neck.Organization Chart Encl ML20207B9301999-05-25025 May 1999 Responds to 990114 Correspondence Re Changes to Plant Defueled Physical Security Plan Rev 1 Submitted Under 10CFR50.54(p).Implementation of Changes Subj to Insp to Confirm Changes Have Not Decreased Security Plan ML20207G1761999-05-21021 May 1999 Forwards Insp Rept 50-213/99-01 on 980119-990419 & Closure of CAL 1-97-010.No Violations Noted.Conduct of Activities Associated with Control of Radiological Work at Haddam Neck Generally Characterized as Careful & Thorough ML20206R8051999-05-12012 May 1999 Responds to 3 Investigations,Repts 1-97-031,008 & 1-98-008 Between 970314 & 980722 as Well as Insp Conducted Between 980720 & 1102.Forwards Synopsis of 3rd OI Investigation ML20206R7021999-05-12012 May 1999 Refers to Investigation 1-97-008 Conducted by Region I & Forwards Notice of Violation.Investigation Found That Recipient Deliberately Attempted to Conceal Release of Contaminated Video Equipment ML20206R7221999-05-12012 May 1999 Refers to Investigation 1-97-031 on 970616-0718 & Forwards Nov.Investigation Found That Recipient Deliberately Did Not Follow Radiation Protection Procedures,Falsified Documents & Provided Incomplete & Inaccurate Info to NRC ML20206C8631999-04-28028 April 1999 Forwards Amend 194 to License DPR-61 & Safety Evaluation. Amend Authorizes Relocation of Requirements Related to Seismic Monitoring Instrumentation from TSs to Technical Requirements Manual ML20206A6871999-04-22022 April 1999 Informs of Completion of Review of Re Nepco in Capacity as Minority Shareholder in Vermont Yankee Nuclear Power Corp,Yaec,Myap & Connecticut Yankee Atomic Power Co IR 05000213/19960121999-04-0505 April 1999 Discusses NRC Insp Repts 50-213/96-12 & 50-213/98-04 on 961102-27 Re Airborne Radioactivity Contamination Event That Occurred in Fuel Transfer Canal & Reactor Cavity in Nov 1996.Notice of Violation Encl ML20205J7931999-04-0505 April 1999 Discusses NRC Insp Repts 50-213/96-12 & 50-213/98-04 on 961102-27 Re Airborne Radioactivity Contamination Event That Occurred in Fuel Transfer Canal & Reactor Cavity in Nov 1996.Notice of Violation Encl ML20207B6641999-02-26026 February 1999 Forwards Insp Rept 50-213/98-06 on 981103-990118 & Notice of Violation Re Locked High Radiation Area Doors That Were Found Unlocked by Staff.Security Program Was Also Inspected ML20203H9621999-02-17017 February 1999 Responds to to Dk Rathbun Which Forwarded Number of Questions from Constituent Re Spent Fuel Decommissioned Nuclear plants.NUREG-1628, Staff Responses to Frequently Asked Questions Re Decommissioning of NPPs Encl.W/O Encl ML20206R6051999-01-11011 January 1999 Ack Receipt of Submiting Sf Mgt Plan.Staff Has Reviewed Plan & Notes Plan to Store Sf in SFP Until DOE Takes Physical Possession of Fuel DD-98-12, Informs That Time Provided by NRC Regulation within Which Commission May Act to Review Director'S Decision DD-98-12 Has Expired.Decision Became Final Agency Action on 981211. with Certificate of Svc.Served on 9812221998-12-22022 December 1998 Informs That Time Provided by NRC Regulation within Which Commission May Act to Review Director'S Decision DD-98-12 Has Expired.Decision Became Final Agency Action on 981211. with Certificate of Svc.Served on 981222 ML20198K8651998-12-21021 December 1998 Ack Receipt of ,Requesting Corrected Pages to Be Issued for License Amend 193,issued on 980630.Informs That Inconsistencies Found When Comparing Corrected Pages Submitted on 981030 & License Amend Application ML20198R1321998-12-21021 December 1998 Forwards Insp Rept 50-213/98-05 on 980720-1102.No Violations Noted.Insp Completes Review of Licensee Actions Described in ,In Response to NOV & Proposed Imposition of Civil Penalties IR 05000213/19980041998-11-27027 November 1998 Forwards Special Insp Rept 50-213/98-04 of Licensee Performance During Reactor Coolant Sys Chemical Decontamination ML20195J3571998-11-19019 November 1998 Forwards Exemption from Certain Requirements of 10CFR50.54(w) & 10CFR140.Exemption Submitted in Response to 971007 Application & Suppls & 1218,requesting Reduction in Amount of Insurance Required for Facility ML20155F8401998-10-29029 October 1998 Forwards Insp Rept 50-213/98-04 on 980720-0911.Four Apparent Violations Involving Failure to Provide Adequate Procedures for RCS Decontamination & Related Activities Being Considered for Escalated Enforcement Action ML20154Q5821998-10-15015 October 1998 Expresses Desire to Confirm Future Involvement with Community Decommissioning Advisory Committee,As NRC Transitions Insp Responsibilities at Plant Site from on-site Resident Inspector to region-based Inspectors ML20154R0351998-10-14014 October 1998 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-213/98-03 Issued on 980821.Ack That Program Improvements for Violations That Occurred During Sys Decontamination,Still in Progress ML20154J9641998-10-0707 October 1998 Ack Receipt of Petition Addressed to E Julian with Forwarding Copies to L Callan,J Hoyle & Commission. Petition Requests That NRC Immediately Revoke or Suspend Util Operating License for Haddam Neck Plant ML20154E2071998-09-28028 September 1998 Final Response to FOIA Request for Documents.App a Records Already Available in Pdr.Forwards App B Records,Being Made Available in PDR ML20153G3721998-09-23023 September 1998 Responds to to Callan,In Which Recipient Supported Citizens Awareness Network Request to Revoke or Suspend Util Operating License for Haddam Neck Plant.Nrc Shares View That Decommissioning of Plant Proceed Safely ML20151Z2961998-09-17017 September 1998 Responds to ,Sent to NRC Region I Office,Re Changes to Haddam Neck Plant Security & Emergency Plans.Nrc Completed Reviews of Plant Defueled Security Plan & Defueled Emergency Plan ML20198K0181998-09-15015 September 1998 Informs That on 980828,NRC Granted Exemption to Connecticut Yankee Atomic Power Co from Certain Sections of 10CFR50 Re Emergency Response Planning,Allowing Licensee to Discontinue Offsite Emergency Planning Activities ML20151Z0061998-09-11011 September 1998 Ack Receipt of Requesting Info Re Connecticut Yankee Plant at Haddam Neck.Ltr Based on Concerns Expressed by Constituent,R Bassilakis,In Ltr of 980707.Copy of NRC Response to R Bassilakis Ltr Encl ML20239A0491998-08-31031 August 1998 Responds to Requesting Info Re Plant & Asking NRC to Take Certain Action Wrt Plant.Licensee Corrective Actions for Events Described as Listed Will Continue to Be Examined ML20238F1981998-08-28028 August 1998 Forwards Exemption from Portion of 10CFR50.54(q) & Approval of Defueled Emergency Plan at Haddam Neck Plant in Response to Application Dtd 970530,as Suppl or Modified by Ltrs Dtd 970919,26,1021,1218,980122,0325,0619 & 0731 ML20237F1281998-08-27027 August 1998 First Partial Response to FOIA Request for Documents. Forwards App a Records Already Available in Pdr.App B Records Being Made Available in PDR ML20237D3941998-08-21021 August 1998 Forwards Insp Rept 50-213/98-03 on 980414-0803 & 13 & Notice of Violation Re Failure to Control Plant Configuration During Valve Manipulations or Tagging Activities ML20236X8151998-07-30030 July 1998 Responds to 980729 & 30 Ltrs to Hj Miller Expressing Concern About Recent Events at Haddam Neck & Requests NRC Intervention at Site.Nrc Closely Monitoring Licensee Current Efforts at RCS Decontamination ML20236T1721998-07-20020 July 1998 Discusses OI Repts 1-96-007,1-96-014,1-96-034 & 1-96-048 Re Multiple Neut Employees.Investigations Initiated to Determine If Employment of Individuals Was Terminated on 960111 for Raising Safety Issues ML20236S1731998-07-15015 July 1998 Forwards Exemption Re Util Request for an Exemption from Requirements of 10CFR73.55 to Discontinue Certain Aspects of Security Plan as Result of Permanently Shutdown & Defueled Status of Reactor ML20236Q7301998-07-0808 July 1998 Ack Receipt of Describing Nuclear Energy Advisory Energy Advisory Council Position on Items Associated with NRC Insp Oversight of Decommissioning Power Reactor Licensees ML20202D1261998-06-30030 June 1998 Forwards Amend 193 to License DPR-61 & Safety Evaluation. Amend Changes Facility Operating License & TS to Reflect Permanently Shutdown & Defueled Status of Plant ML20248G8941998-05-28028 May 1998 Informs That on 961203,Office of Investigations Initiated Investigation to Determine Whether Former Contract Security Dept Employee Terminated in July 1996 for Raising Safety Concern.Insufficient Evidence to Substantiate Claim ML20248F1691998-05-28028 May 1998 Forwards RAI on 2.206 Petition Re Sfpc Methods.Petition Refers to 980311 Meeting at Plant Site ML20248F1401998-05-28028 May 1998 Discusses Request for 3 Month Extension for Station Emergency Response Organization Training.Request for Extension Granted ML20248G9051998-05-28028 May 1998 Informs That on 961203 OI Initiated Investigation 1-96-045 to Determine Whether Former Contract Security Dept Employee at Haddam Neck Facility Terminated in July 1996,for Raising Safety Concerns.Insufficient Evidence to Substantiate Claim ML20248F0841998-05-22022 May 1998 Ack Receipt of Re NRC Oversight Role in Decommissioning of Plant ML20216C5731998-05-13013 May 1998 Forwards Insp Rept 50-213/98-01 on 980113-0413 & Notice of Violation.Areas That Require Further NRC Review Include Maint of Freeze & Flood Protection Measures & Application of Quality for Nuclear Island 1999-09-20
[Table view] |
Text
-. -_
Aprii 7,1987
. Docket No.: 50-213
~
Mr. E. J. Mroczka, Senior Vice President Nuclear Engineering and Operations Northeast Nuclear Energy Company Post Office Box 270 Hartford, Connecticut 06141-0270
Dear Mr. Mroczka:
SUBJECT:
ADDITIONAL TOPICS TO BE ADDED TO THE HADDAM NECK INTEGRATED SAFETY ASSESSMENT In a letter dated December 12, 1986, Connecticut Yankee Atomic Power Company (CYAPCO) submitted a " final report" for the Haddam Neck Integrated Safety Assessment Program (ISAP). This report provided specific details of Northeast Utilities' (NU) integrated assessment and ranked each of the Haddam Neck ISAP topics.
The staff has reviewed the ISAP topic analyses and the Haddam Neck Probabil-istic Safety Study performed by NU. The staff's review of the Haddam Neck Probabilistic Safety Study (PSS) identified two areas where additional eval-uation under ISAP is warranted. These areas are (1) motor control center five (MCC-5) system dependencies and (2) thermal-hydraulic analyses of ex-tended steam generator tube ruptures.
The staff concludes that CYAPC0 should evaluate the following additional topics in the integrated assessment by PRA methods or thermal-hydraulic analysis and should determine what, if any, cost-effective solutions can be achieved to reduce risk or core melt frequency:
Topic 1.64 System Dependencies on MCC-5 Topic 1.65 Steam Generator Tube Rupture Thennal-Hydraulic Analysis A description of the scope of the integrated assessment for each topic is enclosed.
(original signed by)
Cecil 0. Thomas, Director Integrated Safety Assessment
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5 .p WASHINGTON, D. C. 20555 k.....,/ April 7, 1987 Docket No.: 50-213 Mr. E. J. Mroczka, Senior Vice President Nuclear Engineering and Operations Northeast Nuclear Energy Company Post Office Box 270 Hartford, Connecticut 06141-0270
Dear Mr. Mroczka:
SUBJECT:
ADDITIONAL TOPICS TO BE ADDED TO THE HADDAM NECK INTEGRATED SAFETY ASSESSMENT In a letter dated December 12, 1986, Connecticut Yankee Atomic Power Company (CYAPC0) submitted a " final report" for the Haddam Neck Integrated Safety Assessment Program (ISAP). This report provided specific details of Northeast Utilities' (NU) integrated assessment and ranked each of the Haddam Neck ISAP topics.
The staff has reviewed the ISAP topic analyses and the Haddam Nect Probabil-istic Safety Study performed by NU. The staff's review of the Haddam Neck Probabilistic Safety Study (PSS) identified two areas where additional eval-uation under ISAP is warranted. These areas are (1) motor control center five (MCC-5) system dependencies and (2) thermal-hydraulic analyses of ex-tended steam generator tube ruptures.
The staff concludes that CYAPC0 should evaluate the following additional topics in the integrated assessment by PRA methods or thermal-hydraulic analysis and should determine what, if any, cost-effective solutions can be achieved to reduce risk or core melt frequency:
Topic 1.64 System Dependencies on MCC-5 Topic 1.65 Steam Generator Tube Rupture Thermal-Hydraulic Analysis A description of the scope of the integrated assessment for each topic is enclosed.
Cada O. O/dpu-w Cecil 0. Thomas, Director Integrated Safety Assessment Project Directorate Division of PWR Licensing-B Office of Nuclear Reactor Regulation
Enclosure:
As stated cc: See next page
6 Mr. Edward J. Mroczka Connecticut Yankee Atomic Power Company Haddam Neck Plant cc:
Gerald Garfield, Esquire Kevin McCarthy, Director Day, Berry & Howard Radiation Control Unit Counselors at Law Department of Environmental City Place Protection Hartford, Connecticut 06103-3499 State Office Building Hartford, Connecticut 06106 Superintendent Haddam Neck Plant Richard M. Kacich, Manager l RFD #1 Generation Facilities Licensing Post Office Box 127E Northeast Utilities Service Company East Hampton, Connecticut 06424 Post Office Box 270 Hartford, Connecticut 06141-0270 Wayne D. Romberg Vice President, Nuclear Operations Northeast Utilities Service Company Post Office Box 270 Hartford, Connecticut 06141-0270 Board of Selectmen Town Hall Haddam, Connecticut 06103 State of Connecticut Office of Policy and Management ATTN: Under Secretary Energy Division 80 Washington Street Hartford, Connecticut 06106 Resident Inspector Haddam Neck Nuclear Power Station l c/o U.S. NRC P. O. Box 116 East Haddam Post Office East Haddam, Connecticut 06423 Regional Administrator, Region !
U.S. Nuclear Regulatory Commission 631 Park Avenue -
King of Prussia, Pennsylvania 19406
i ENCLOSURE 1
Additional Haddam Neck ISAP Topics Topic 1.64 - System Dependencies on MCC-5
Background
One of the insights gained from the Haddam Neck PSS and its review is that failure of MCC-5, both as an initiating event and as a failure sub-sequent to other intitiating events, is a significant contributor to the total core melt frequency of the Haddam Neck plant. The loss of power on 1 MCC-5 is a significant contributor to estimated core melt frequency, pri-marily because of the dependence of reactor coolant pump (RCP) seal cooling on MCC-5. Both the RCP seal cooling (provided by the charging system) and thermal barrier cooling (provided by the component cooling water system) are dependent on MCC-5 either directly or indirectly through other support systems such as the control air system.
Additionally, several accident mitigation systems are dependent on MCC-5.
These systens include the service water system, the high pressure safety injection system, the low pressure safety injection system, the residual heat removal system, the main feedwater system, the emergency boration system, and others which are all at least partially dependent on MCC-5.
, In the Haddam Neck PSS, the failure of MCC-5 contributes approximately 6E-5 per year of the total core melt frequency. This figure is slightly more than 10% of the total core melt frequency. Of the 6E-5 per year, i
3E-5 per year is the result of the loss of MCC-5 as an initiating event.
The staff's reanalysis of MCC-5, based on the data developed during the review of the Haddam Neck PSS, estimates that failure of MCC-5 contributes
) approximately 1E-4 per year to the total core melt frequency.
Proposed Project Under this topic, CYAPC0 should analyze different options designed to re-duce the contribution failure of MCC-5 makes to core melt frequency. The licensee has already proposed to build a new switchgear room. The con-ceptual design for the new switchgear room includes a new 480 V bus and 480 V MCC. Several components necessary for charging system operation (including some component cooling water system components) are part of the proposed set of components to be fed from the new switchgear room. Many of these components are being transferred from MCC-5. However, the proposed MCC does not appear to supply power to any air compressors or semi-vital AC distribution panels. Thus, the new MCC would not create a redundant power supply to the above system. In addition, the conceptual design for this switchgear room does not appear to include an alternative power supply.
a l The objective of this topic is to assess the benefits associated with addition of loads and power supplies to the new MCC such as (1) the air compressors, (2) the semi-vital AC distribution panels, and (3) an alter-native power supply.
Based on information in the Haddam Neck PSS, it appears that elimination of MCC-5 as an initiator would require that semi-vital AC and the instru-ment air system not fail on a loss of MCC-5. This modification could be accomplished either by splitting MCC-5 into two MCCs with no automatic bus transfers or by altering the loads powered by MCC-5 and the new MCC as discussed above. With either of these modifications, it dcas not appear that a loss of MCC-5 alone would result in a plant trip. Additional efforts
- to separate other loads currently powered by MCC-5 could lead to further I estimated core melt frequency reductions.
Analysis i Currently, it appears that both semi-vital AC power and the control air systems fail on a loss of power to MCC-5. Both the preferred and alter-
,t native power feeds to the semi-vital AC panels are through MCC-5. All three control air compressors are powered through MCC-5. A review of the loads on MCC-5 suggests that the loss of these two systems is the reason the plant will trip on a loss of MCC-5. Therefore, it would seem possible to eliminate the loss of power on MCC-5 as an initiating event if the semi-vital AC power cystem and the control air system were not solely dependent on MCC-5 for power. This action could be achieved by chang-l ing the alternative source of power for the semi-vital AC distribution
- panels and by moving one control air compressor to a different MCC.
1 To maintain the same reliability for the power supplies to these relocated electrical loads, it would be necessary to place these loads on an MCC with characteristics similar to MCC-5; that is, an MCC with pre-2 ferred and alternative power supplies and an automatic bus transfer.
l Eliminating the loss of power on MCC-5 as an initiator results in elimina-4 tion of the 7E-5 per year contribution to core melt frequency, based on the
! results of the Haddam Neck PSS review. However, a small increase in the loss of semi-vital AC power initiating event frequency would be expected.
Since the loss of power on MCC-5 was an initiating event that resulted in the loss of semi-vital AC, the loss of power to the semi-vital AC power system (MCC-5) was not evaluated as part of the loss of semi-vital AC power as an initiating event. With the new design, loss of MCC-5 and failure of the semi-vital AC power automatic bus transfer would result in loss of semi-vital AC power. This additional contribution to the semi-vital AC power initiating event frequency would be 1
F(sv) = F(MCC-5) x P f
.' where F(sv) is the change in the loss of semi-vital AC power frequency F(MCC-5) is the loss of MCC-5 frequency = 2E-3 per year P is the probability of the failure to transfer on loss of power to semi-vital AC distribution panels = 2E-2 (from the Haddam Neck PSS).
The increase in the frequency of loss of semi-vital AC power would be 4E-5 per year. This corresponds to an increase of 3E-7 per year in the core melt frequency. In the Haddam Neck PSS the loss of semi-vital AC power contributed 2E-5 per year to the core melt frequency, with an in-itiating event frequency of 2E-3 per year. This is negligible when compared to the potential reduction gained through the elimination of the loss of MCC-5 as an initiating event.
Such a design change would also help reduce the contribution of the failure of MCC-5 as a support system to the core melt frequency. With the cur-rent plant configuration, the charging system is shut down on a loss of MCC-5. The letdown line isolates and cooling to the RCP seals via the charging system is lost. With design modifications, seal cooling need not be lost because of a failure of MCC-5. Since control air and semi-vital AC are not lost on a failure of MCC-5, it appears that the charging system would not be tripped on a loss of either MCC-5 or the MCC located in the new switchgear room. Based on the results of the Haddam Neck PSS review, this change has the potential to futher reduce the core melt frequency by approximately 3E-5 per year. (It should be noted that the total possible reduction based on the Haddam Neck PSS is nearly 6E-5 per year, with a reduction of a little more than 3E-5 per year resultin event.) g from the elimination of the loss of MCC-5 as an initiating Topic 1.65 - Steam Generator Tube Rupture Thermal-Hydraulic Analysis
Background
l In the Haddam Neck PSS, t N event tree for the steam generator tube rupture (SGTR) appears to have been developed based on the assumption that if the secondary steam relief valves are stuck open and loop isolation valves are not closed, depressurization of the primary system along with long-term decay heat removal results in a safe condition.
The thermal-hydraulic analysis of this event provided in the Connecticut Yankee Best Estimate LOCA Analysis, NUSCO-150, only carries the evaluation of this event to the point at which the Refueling Water Storage Tank is depleted. This is approximately 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after the initiation of the ac-cident. Thus, the evaluation is not carried out long enough to determine if the primary pressure could be reduced sufficiently to preclude con-tinuous loss of coolant to a steam generator that is essentially at
' atmospheric pressure. In the absence of this thermal-hydraulic analysis, the staff assumes that if the secondary steam relief valves are stuck open and the primary loop is not isolated, the coolant will be lost to the atmosphere, and core melt will result in about 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after the initiation of the accident. As a result of this change, the SGTR core melt frequency in the staff's model increased by a factor of 5 compared to the PSS.
Proposed Project In the staff's revised model generated as a result of the review of the Haddam Neck PSS, the assumption that an SGTR coincident with a stuck-open secondary steam relief valve and failure of primary loop isolation could lead to core meltdown resulted in a new dominant core melt sequence. This sequence in the Haddam Neck PSS review is described as follows: SG cooling available, high pressure injection available, SG isolation successful, secondary safety relief valve fails to reseat, reactor coolant loop isolation fails. The frequency of this sequence was estimated to be 4E-5 per year. Thus, if the thermal-hydraulic analysis indicates that this sequence does not lead to core meltdown, the total estimated core melt frequency in the staff's revised model would be reduced by 4E-5 ;r year.
The staff proposes that CYAPC0 perform the necessary thermal-hydraulic analysis for the above sequence. The evaluation should be carried out until either a stable core condition or a core melt situation is reached.
The results of this thermal-hydraulic analysis would then be used to make decisions about any other actions related to this topic.
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