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Category:CORRESPONDENCE-LETTERS
MONTHYEARML20217K1051999-10-19019 October 1999 Ack Receipt of Ltr Dtd 990707,which Transmitted Rev 29 to Callaway Plant Physical Security Plan,Under Provisions of 10CFR50.54(p).Based on Determination That Changes Do Not Decrease Effectiveness of Plan,No NRC Approval Required ML20217G2071999-10-14014 October 1999 Forwards Insp Rept 50-483/99-10 on 990913-16.No Violations Noted.Insp Was to Review Emergency Plan & Procedures During Biennial Emergency Preparedness Exercise ML20217B5901999-10-0505 October 1999 Informs That Staff Concludes That Licensee Responses to GL 97-06 Provides Reasonable Assurance That Condition of Util SG Internals in Compliance with Current Licensing Bases for Callaway Plant,Unit 1 ML20217B5711999-10-0505 October 1999 Discusses GL 98-01 Issued by NRC on 980511 & Uec Responses for Callaway NPP Unit 1 ,990224 & 990628.Informs That Staff Reviewed Responses & Concluded That All Requested Info for GL 98-01 Provided ML20212G0221999-09-22022 September 1999 Forwards Insp Rept 50-483/99-11 on 990812-20.No Violations Noted.Team Found,Weakness in flow-accelerated Corrosion Monitoring Program Resulted in No Previous Insp of Pipe Segment Which Failed ML20212D9341999-09-16016 September 1999 Informs That on 990818,NRC Completed Midcycle PPR of Callaway Plant.In Area of Ep,C/As Taken in Response to Problems Identified During Previous Exercises Warrant More in-dept Review.Details of Insp Plan Through March 2000 Encl ML20217D5791999-09-15015 September 1999 Provides Formal Documentation of Reviews & Discussions Re Technical Ltr Rept for Proprietary Info.Review of Ltr Was Discussed in Telcon & Via e-mail Messages. Summary of Telcons as Documented on 990708,included ML20212A4921999-09-13013 September 1999 Forwards Insp Rept 50-483/99-08 on 990725-0904.Two Severity Level IV Violations of NRC Requirements Identified & Being Treated as Noncited Violations Consistent with App C of Enforcement Policy ML20212A4701999-09-10010 September 1999 Rssponds to NRC 990709 RAI Re Util Relief Request to Allow Use of 1998 Edition of ASME Section Xi,Subsection Iwe. Acceptance Criteria for Liner Plate Pressure Boundary Thickness Will Be Limited to 10% Nominal Thinning ML20212B1521999-09-10010 September 1999 Forwards Insp Rept 50-483/99-07 on 990809-13.No Violations Noted.Inspectors Used Annual Licensed Operator Requalification Exams to Assess Licensed Operator Performance ML20211N0321999-09-0202 September 1999 Forwards SE Concluding That Util Adequately Addressed Actions Requested in GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves ML20211B0241999-08-18018 August 1999 Ack Receipt of Ltr Dtd 990714,transmitting Scenario for Licensee Upcoming Biennial Exercise.Based on Review,Nrc Determined That Exercise Scenario Sufficient to Meet Emergency Plan Requirements & Exercise Objectives ML20210T9121999-08-13013 August 1999 Forwards Insp Rept 50-483/99-06 on 990613-0724.One Severity Level 4 Violation Occurred & Being Treated as Ncv,Consistent with App C of Enforcement Policy ML20210R7241999-08-12012 August 1999 Forwards semi-annual Fitness for Duty Program Performance Data Rept for Callaway Nuclear Plant for 990101-990630,IAW 10CFR26.71(d) 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 ULNRC-04085, Forwards Rev 4 to Callaway Plant Cycle 10 COLR, Per TS 6.9.1.9.COLR Has Been Revised to Update Rod Bank Insertion (Ril) Limits,As Function of Rated Thermal Power1999-08-11011 August 1999 Forwards Rev 4 to Callaway Plant Cycle 10 COLR, Per TS 6.9.1.9.COLR Has Been Revised to Update Rod Bank Insertion (Ril) Limits,As Function of Rated Thermal Power ML20210P0371999-08-10010 August 1999 Forwards SE Granting Licensee 980710 Requests for Relief (ISI-13 - ISI-18) from Requirements of Section XI of 1989 Edition of ASME B&PV Code for Second 10-year Interval ISI at Plant,Unit 1 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 ULNRC-04079, Forwards 180-day Response to NRC GL 99-02, Lab Testing of Nuclear-Grade Activated Charcoal1999-08-0202 August 1999 Forwards 180-day Response to NRC GL 99-02, Lab Testing of Nuclear-Grade Activated Charcoal ML20210H6381999-07-30030 July 1999 Forwards SE Accepting Relief Request for Approval for Use of Alternate Exam Requirement for Plant Inservice Insp Program A93443, Forwards Addl Info as Committed to in Telcon Between Amerenue & NRC Personnel on 990616,re GL 95-07, Pressure Locking & Thermal Binding of MOV Gate Valves1999-07-28028 July 1999 Forwards Addl Info as Committed to in Telcon Between Amerenue & NRC Personnel on 990616,re GL 95-07, Pressure Locking & Thermal Binding of MOV Gate Valves ULNRC-04075, Forwards Response to NRC 990618 RAI Re GL 96-05, Periodic Verification of Design-Basis Capability of SR Motor-Operated Valves1999-07-28028 July 1999 Forwards Response to NRC 990618 RAI Re GL 96-05, Periodic Verification of Design-Basis Capability of SR Motor-Operated Valves ULNRC-04076, Informs of Implementation of Amend 131 to License NPF-30, Revising OL to Reflect Requirement in TS 3/4.7.1.7 for Four Operable ASD Lines & Associated Revs,Rather than Three Operable ASDs1999-07-28028 July 1999 Informs of Implementation of Amend 131 to License NPF-30, Revising OL to Reflect Requirement in TS 3/4.7.1.7 for Four Operable ASD Lines & Associated Revs,Rather than Three Operable ASDs ULNRC-04070, Forwards Rev 3 to Callaway Plant Cycle 10 COLR, IAW TS 6.9.1.9.COLR Has Been Revised to Update RAOC Axial Flux Difference (Afd) Limits,As Function of Rated Thermal Power1999-07-27027 July 1999 Forwards Rev 3 to Callaway Plant Cycle 10 COLR, IAW TS 6.9.1.9.COLR Has Been Revised to Update RAOC Axial Flux Difference (Afd) Limits,As Function of Rated Thermal Power 05000483/LER-1998-008, Forwards Amended Response to GL 81-07, Control of Heavy Loads, to Address Corrective Action Described in LER 98-008-00.Discrepancy Between Earlier Submittals of Snupps Rept on Control of Heavy Loads & TS Re RHR Sys,Resolved1999-07-27027 July 1999 Forwards Amended Response to GL 81-07, Control of Heavy Loads, to Address Corrective Action Described in LER 98-008-00.Discrepancy Between Earlier Submittals of Snupps Rept on Control of Heavy Loads & TS Re RHR Sys,Resolved ULNRC-04071, Informs That Util Anticipates Approx Ten Licensing Actions That Could Occur During Fys 2000 & 2001,in Response to Administrative Ltr 99-021999-07-27027 July 1999 Informs That Util Anticipates Approx Ten Licensing Actions That Could Occur During Fys 2000 & 2001,in Response to Administrative Ltr 99-02 ML20210B5611999-07-20020 July 1999 Forwards Review of Ltr & Encl Objectives for Plant,Unit 1,1999 Emergency Plan Exercise Scheduled for 990914 ML20210B4021999-07-19019 July 1999 Ack Receipt of Facility Emergency Plan Implementing Procedure EIP-ZZ-00101, Classification of Emergencies, Rev 23,issued on 990513,under Provisions of 10CFR50,App E, Section V ML20210B4401999-07-19019 July 1999 Ack Receipt of Revs to Facility Radiological Emergency Response Plan,Chapters 8.0 & 4.0,issued Respectively on 990512-14,under Provisions of 10CFR50,App E,Section V ML20212A3291999-07-15015 July 1999 Forwards Scenario Manual Containing Description of Callaway Plant 1999 Biennial Emergency Response Plan Exercise to Be Conducted 990914.Correspondence to Satisfy 60-day Submittal Requirement ML20209F3471999-07-0909 July 1999 Forwards Response to NRC 990624 RAI to Complete NRC Review of Relief Request to Allow Use of 1998 Edition of ASME Section Xi,Subsection IWE ML20209E5591999-07-0808 July 1999 Informs That as Result of NRC Review of Util Responses to GL 92-01,rev 1,suppl 1 & Suppl 1 Rai,Staff Revised Info in Reactor Vessel Integrity Database & Releasing Database as Rvid Version 2.TAC MA0531 Closed ML20209H2471999-07-0707 July 1999 Forwards Rev 29 to Physical Security Plan,Per 10CFR50.54(p). Rev Withheld,Per 10CFR73.21 ML20196J9501999-07-0202 July 1999 Ack Receipt of Plant Ep,Rev 22,received on 981207 & Submitted Under Provision of 10CFR50,App E,Section V.Changes Does Not Decrease Effectiveness of EP & Continues to Meet Stds of 10CFR50.47(b).NRC Approval Not Required ML20209B6851999-06-28028 June 1999 Responds to GL 98-01,Suppl 1, Y2K Readiness of Computer Systems at Nuclear Power Plants. Disclosure Rept Encl ML20209C0171999-06-28028 June 1999 Forwards Special Rept 99-01 Re Fifteenth Year Inservice Containment Bldg Tendon Surveillance Failure.Observed Voids in Sheathing Filler Grease Do Not Indicate Degradation of post-tensioning Sys,Based on Encl Evaluation ML20196F8101999-06-25025 June 1999 Informs That J Donohew Will Assume Project Manager Responsibilities,Effective 990621 ML20196H2521999-06-25025 June 1999 Forwards Insp Rept 50-483/99-05 on 990502-0612.Two Violations Occurred & Being Treated as Noncited Violations, Consistent with App C of Enforcement Policy ML20196F8181999-06-24024 June 1999 Forwards RAI Re 990111 Request for Relief from Certain ASME Code ISI Requirements for Containment Liners.Response Requested within 30 Days from Date of Agreement ML20196G5621999-06-21021 June 1999 Informs NRC of Implementation of Amend 132 to Callaway License NPF-30 to Allows Installation of Electrosleeves for Steam Generator Tube Repair for Two Cycles Following Installation of First Electrosleeve IR 05000483/19990041999-06-18018 June 1999 Refers to GL 96-05 Issued by NRC on 960918,UE Responses & 970313 & NRC Insp Rept 50-483/99-04,dtd 990427. Forwards Request for Addl Info Re GL 96-05 Program at Callaway Plant,Unit 1 ML20212J2441999-06-18018 June 1999 Submits Request for Alternate Exam Requirements for Plant Re ISI Program Plan.Plant Does Not Torque Bolted Connections to Stress Values Greater than 100 Ksi ML20195H0971999-06-14014 June 1999 Discusses Une 990407 Request That Proprietary Document Entitled, Thermal Stability Assessment - Electrosleeved Tubes, Be Withheld from Public Disclosure.Determined Info to Be Proprietary & Will Be Withheld from Public Disclosure ML20207H3751999-06-14014 June 1999 Discusses 990407 Une Request That Proprietary Version of Document Entitled, Evaluation of Severe Accident Simulation, Dtd April 1999,be Withheld from Public Disclosure.Determined Info Proprietary & Will Be Withheld ML20195H9731999-06-11011 June 1999 Forwards Requested Addl Info Related to Relief Request ISI-16,encountered During Refuel 9 ML20195J9301999-06-0808 June 1999 Informs That Refuel 9 OAR-1 Owners Data Rept for ISI & Summary Rept for Interval 2 Was Submitted with Typographical Error,In That Commercial Service Date Should Be 841219,vice 941219.Please Substitute Encl Corrected Document ML20207G3201999-06-0707 June 1999 Ack Receipt of Change Notice 98-008 Dtd 980918,which Transmitted Changes to Callaway Plant Ep,Rev 21,under Provisions of 10CFR50,App E,Section V.No NRC Approval Required.No Violations Identified ML20207G3151999-06-0707 June 1999 Ack Receipt of Callaway Plant EP Implementing Procedure EIP-ZZ-001001M,Classification of Emergencies,Rev 22,issued on 981222 Under 10CFR50,App E,Section V Provisions.No Violations Identified ML20195C5131999-05-28028 May 1999 Forwards Revs to Sections 3.9 & 5.6 of Its,Based on Resolution Telcons Held Between NRC Staff & Util on 990526 & 27 A98803, Forwards Certified ITS & ITS Bases for Callaway Plant,In Response to NRC 990402 Draft SE for License Amend to Convert TSs to Format & Expanded Bases of ITS1999-05-27027 May 1999 Forwards Certified ITS & ITS Bases for Callaway Plant,In Response to NRC 990402 Draft SE for License Amend to Convert TSs to Format & Expanded Bases of ITS 1999-09-22
[Table view] Category:NRC TO UTILITY
MONTHYEARML20062E5581990-11-14014 November 1990 Forwards Safety Insp Rept 50-483/90-18 on 901001-03 & 1105. No Violations Noted ML20058C0941990-10-23023 October 1990 Forwards Safety Insp Rept 50-483/90-16 on 901001-05.No Violations Noted ML20062B5711990-10-18018 October 1990 Forwards Safety Insp Rept 50-483/90-15 on 900816-0930.No Violations Noted ML20059N7151990-10-0505 October 1990 Forwards Request for Addl Info Re Seismic Design Consideration for Plant Refueling Water Storage Tank. Response Requested within 90 Days of Ltr Receipt ML20059H6281990-09-13013 September 1990 Responds to Re Plant Fitness for Duty Program. Any Subsequent Confirmed Positive Test,No Matter How Many Yrs Elapsed Must Be Treated as Second Confirmed Positive,Per 10CFR26,Section 26.27(b)(2) ML20059H2591990-09-0707 September 1990 Advises That 900604 Rev 12 to Operational QA Manual Meets Requirements of 10CFR50,App B & Acceptable ML20059F1031990-08-31031 August 1990 Forwards Insp Rept 50-483/90-14 on 900831.No Violations Noted ML20059E0981990-08-28028 August 1990 Forwards Safety Insp Rept 50-483/90-13 on 900701-0815. Violations Noted Met Requirements of 10CFR2,App C,Section V.G.1 & No Notice of Violation Issued ML20059A1641990-08-10010 August 1990 Confirms Mgt Meeting on 900828 in Region III Ofc to Discuss Items of Mutual Interest,Per 900718 Discussion ML20058M6141990-08-0707 August 1990 Forwards Sample Registration Ltr for 901010 Generic Fundamentals Section of Written Operator Licensing Exam. Registration Ltr Listing Names of Candidates Taking Exam Should Be Submitted to Region 30 Days Prior to Exam Date ML20056A5591990-08-0606 August 1990 Forwards Safety Evaluation Re Util 860108 Steam Generator Tube Rupture Analysis ML20059A7291990-08-0606 August 1990 Provides Comments on 891228 Response to Generic Ltr 89-10, Safety-Related Motor-Operated Valve Testing & Surveillance. NRC Accepts Request to Submit Only Changes to Commitments Significant in Nature ML20058M0741990-08-0202 August 1990 Ack Receipt of 900604 Changes to QA Program Description ML20055J2961990-07-25025 July 1990 Requests Util to Inform NRC of Significant Changes in Estimated Completion Schedule,Per Util Response to Generic Ltr 88-17, Loss of Dhr. Response to Generic Ltr Acceptable ML20055J4391990-07-23023 July 1990 Advises That 900621 Rev 13 to Radiological Emergency Response Plan Acceptable.Rev Includes Clarifications to Emergency Action Levels & Changes to Position Titles & Responsibilities in Plant Organization ML20055G3681990-07-13013 July 1990 Forwards Safety Insp Rept 50-483/90-12 on 900516-0630.No Violations Noted ML20059M8691990-06-13013 June 1990 Forwards NRC Performance Indicators for First Quarter 1990. W/O Encl ML20055C2821990-02-16016 February 1990 Forwards Safety Insp Rept 50-483/90-03 on 900124-25 & 900131 Telcon.No Violations Noted ML20248C6171989-09-25025 September 1989 Forwards Amend 3 to Indemnity Agreement B-93,reflecting Changes to 10CFR140,effective 890701.Util Requested to Submit Signed Amend to Signify Acceptance ML20248A5621989-09-22022 September 1989 Forwards Safety Insp Rept 50-483/89-17 on 890821-25.No Violations Noted ML20247E9021989-09-0808 September 1989 Forwards Safety Insp Rept 50-483/89-16 on 890821-25.No Violations Noted ML20246K7141989-08-28028 August 1989 Forwards Safety Insp Rept 50-483/89-14 on 890717-0803.No Violations Noted ML20245H5921989-08-11011 August 1989 Advises That 890609 Rev 12 to Operating QA Manual Meets Requirements of 10CFR50,App B & Acceptable ML20245J6271989-08-0101 August 1989 Informs That Facility Chosen for Safeguards Regulatory Effectiveness Review (Rer) Scheduled for Wk of 890918-22. Appropriate Plant Personnel Support Should Be Provided for Three Rer Team Subgroups During Scheduled Review ML20247P7231989-07-31031 July 1989 Requests Addl Info Re 890320 Request for Exemption from 10CFR50,App J Re Interpretation to Leave Leak Chases Plugged During Integrated Leak Rate Test ML20247R7901989-07-28028 July 1989 Forwards Safety Insp Rept 50-483/89-11 on 890601-0715.No Violations Noted ML20247K2811989-07-21021 July 1989 Forwards Addendum to Insp Rept 50-483/88-08 Re Comparison of Results Between Analyses Performed on Liquid Spike & Monitor Tank Sample.Tank Results in Insp Rept 50-483/88-17 ML20247G6461989-07-21021 July 1989 Advises That 871130,880719 & 890727 Simulator Certification Submittals Found Complete for Use in Administering Operating Tests ML20247H7101989-07-20020 July 1989 Requests Reclassification of Diesel Generator a Failure. Failure Should Be Classified as Valid Test & Failure,Not Invalid Failure Due to Listed Reasons ML20247C4531989-07-19019 July 1989 Forwards Safeguards Insp Rept 50-483/89-12 on 890626-0707.No Violations Noted ML20247D1891989-07-17017 July 1989 Ack Receipt of 890628 Submittal of Description of Scope, Objectives & Guidelines for 1989 Emergency Preparedness Exercise Scheduled for 891011.Initial Concerns W/Objective 14 Resolved in Telcon.No Other Concerns Expressed ML20246P9171989-07-17017 July 1989 Discusses Environ Qualification of Bunker Ramo Electrical Penetration Assemblies at Facility,Specifically NRC Concerns Re Low Insulation Resistance Readings on Control Circuits. Qualification File May Be Subj to NRC Audit ML20245K0911989-06-28028 June 1989 Advises That Reactor Operator & Senior Reactor Operator Written & Oral Exams Scheduled for Wk of 891016.Ref Matls, Listed on Encl,Should Be Provided at Least 30 Days Prior to Exams ML20245K3961989-06-22022 June 1989 Forwards Safety Insp Rept 50-483/89-09 on 890401-0531.No Violations Noted ML20244E0661989-06-13013 June 1989 Forwards FEMA Final Rept of 890222 offsite-related Unannounced Drill.W/O Encl ML20244B4371989-06-0707 June 1989 Confirms Plans for Mgt Meeting & Site Tour by AB Davis & Eg Greenman on 890621 in Steedman,Mo.General Plant Performance Will Be Discussed at Meeting ML20247P2001989-06-0101 June 1989 Forwards Safety Insp Rept 50-483/89-08 on 890328-30,0417-20 & 0515.No Violations Noted ML20248C2251989-05-30030 May 1989 Forwards Safety Insp Rept 50-483/89-10 on 890501-05 & 11.No Violations Noted ML20247L8651989-05-24024 May 1989 Concurs W/Util 881130 Response to Generic Ltr 88-11, Indicating That Draft Rev 2 to Reg Guide 1.99 Currently Used to Predict Effect of Neutron Radiation on Reactor Vessel Matls ML20247H5791989-05-23023 May 1989 Requests Listed Info in Order to Make Final Determination That Potential Safety Issues Exists Re Ability of safety- Related above-ground Vertical Liquid Storage Tanks to Maintain Structural Integrity.Nrc Recommended Method Encl ML20247D5071989-05-19019 May 1989 Requests That Licensee Submit Info Requested by Advisory Council on Historic Preservation Re Cultural Resources ML20247D1131989-05-19019 May 1989 Informs of Implementation Schedule for NRC Bulletin 88-011, Item,1.b, Pressurizer Surge Line Thermal Stratification, Mutually Agreed Upon Between NRC & Westinghouse Owners Group During 890411 Meeting ML20247D7281989-05-16016 May 1989 Forwards FEMA Evaluation of Unannounced Drill Testing Mobilization & Activation Portions of State & Local Radiological Emergency Response Plans, from Drill Conducted on 890222.No Deficiencies Noted ML20246K7161989-05-0909 May 1989 Discusses TMI Action Item II.K.3.17 Re ECCS Outages.Nrc Considers Requirements of 10CFR50.72 & 73 & Industry Efforts to Rept on NPRDS to Be Adequate for Reporting ECCS Outages. Special Rept from Plant Not Needed to Fulfill Item ML20245C6921989-04-18018 April 1989 Advises That 890302 Request for Review & Approval of Changes to Unusual Event Initiating Condition for Emergency Plan Sent to Headquarters for Resolution ML20244E3001989-04-14014 April 1989 Forwards Safety Insp Rept 50-483/89-07 on 890403-06.No Violations Noted ML20245A4591989-04-13013 April 1989 Forwards Safety Insp Rept 50-483/89-04 on 890216-0331.No Violations Noted ML20247K5181989-03-30030 March 1989 Advises That 890330 Response to Generic Ltr 88-14, Instrument Supply Problems Affecting Safety-Related Equipment, Satisfactory.Item Closed ML20247G4491989-03-24024 March 1989 Forwards Info on Development of risk-based Insp Guide for Facility as Followup to & 890222 Telcon.Technique Used to Produce risk-based Insp Guide to Differ from Method Being Described in Encl Rept ML20246P4781989-03-21021 March 1989 Forwards Safeguards Insp Rept 50-483/89-03 on 890213-23 & Notice of Violation.Notice of Violation Withheld (Ref 10CFR73.21) 1990-09-07
[Table view] Category:OUTGOING CORRESPONDENCE
MONTHYEARML20217K1051999-10-19019 October 1999 Ack Receipt of Ltr Dtd 990707,which Transmitted Rev 29 to Callaway Plant Physical Security Plan,Under Provisions of 10CFR50.54(p).Based on Determination That Changes Do Not Decrease Effectiveness of Plan,No NRC Approval Required ML20217G2071999-10-14014 October 1999 Forwards Insp Rept 50-483/99-10 on 990913-16.No Violations Noted.Insp Was to Review Emergency Plan & Procedures During Biennial Emergency Preparedness Exercise ML20217B5901999-10-0505 October 1999 Informs That Staff Concludes That Licensee Responses to GL 97-06 Provides Reasonable Assurance That Condition of Util SG Internals in Compliance with Current Licensing Bases for Callaway Plant,Unit 1 ML20217B5711999-10-0505 October 1999 Discusses GL 98-01 Issued by NRC on 980511 & Uec Responses for Callaway NPP Unit 1 ,990224 & 990628.Informs That Staff Reviewed Responses & Concluded That All Requested Info for GL 98-01 Provided ML20212G0221999-09-22022 September 1999 Forwards Insp Rept 50-483/99-11 on 990812-20.No Violations Noted.Team Found,Weakness in flow-accelerated Corrosion Monitoring Program Resulted in No Previous Insp of Pipe Segment Which Failed ML20212D9341999-09-16016 September 1999 Informs That on 990818,NRC Completed Midcycle PPR of Callaway Plant.In Area of Ep,C/As Taken in Response to Problems Identified During Previous Exercises Warrant More in-dept Review.Details of Insp Plan Through March 2000 Encl ML20212A4921999-09-13013 September 1999 Forwards Insp Rept 50-483/99-08 on 990725-0904.Two Severity Level IV Violations of NRC Requirements Identified & Being Treated as Noncited Violations Consistent with App C of Enforcement Policy ML20212B1521999-09-10010 September 1999 Forwards Insp Rept 50-483/99-07 on 990809-13.No Violations Noted.Inspectors Used Annual Licensed Operator Requalification Exams to Assess Licensed Operator Performance ML20211N0321999-09-0202 September 1999 Forwards SE Concluding That Util Adequately Addressed Actions Requested in GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves ML20211B0241999-08-18018 August 1999 Ack Receipt of Ltr Dtd 990714,transmitting Scenario for Licensee Upcoming Biennial Exercise.Based on Review,Nrc Determined That Exercise Scenario Sufficient to Meet Emergency Plan Requirements & Exercise Objectives ML20210T9121999-08-13013 August 1999 Forwards Insp Rept 50-483/99-06 on 990613-0724.One Severity Level 4 Violation Occurred & Being Treated as Ncv,Consistent with App C of Enforcement Policy 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 ML20210P0371999-08-10010 August 1999 Forwards SE Granting Licensee 980710 Requests for Relief (ISI-13 - ISI-18) from Requirements of Section XI of 1989 Edition of ASME B&PV Code for Second 10-year Interval ISI at Plant,Unit 1 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 ML20210H6381999-07-30030 July 1999 Forwards SE Accepting Relief Request for Approval for Use of Alternate Exam Requirement for Plant Inservice Insp Program ML20210B5611999-07-20020 July 1999 Forwards Review of Ltr & Encl Objectives for Plant,Unit 1,1999 Emergency Plan Exercise Scheduled for 990914 ML20210B4401999-07-19019 July 1999 Ack Receipt of Revs to Facility Radiological Emergency Response Plan,Chapters 8.0 & 4.0,issued Respectively on 990512-14,under Provisions of 10CFR50,App E,Section V ML20210B4021999-07-19019 July 1999 Ack Receipt of Facility Emergency Plan Implementing Procedure EIP-ZZ-00101, Classification of Emergencies, Rev 23,issued on 990513,under Provisions of 10CFR50,App E, Section V ML20209E5591999-07-0808 July 1999 Informs That as Result of NRC Review of Util Responses to GL 92-01,rev 1,suppl 1 & Suppl 1 Rai,Staff Revised Info in Reactor Vessel Integrity Database & Releasing Database as Rvid Version 2.TAC MA0531 Closed ML20196J9501999-07-0202 July 1999 Ack Receipt of Plant Ep,Rev 22,received on 981207 & Submitted Under Provision of 10CFR50,App E,Section V.Changes Does Not Decrease Effectiveness of EP & Continues to Meet Stds of 10CFR50.47(b).NRC Approval Not Required ML20196F8101999-06-25025 June 1999 Informs That J Donohew Will Assume Project Manager Responsibilities,Effective 990621 ML20196H2521999-06-25025 June 1999 Forwards Insp Rept 50-483/99-05 on 990502-0612.Two Violations Occurred & Being Treated as Noncited Violations, Consistent with App C of Enforcement Policy ML20196F8181999-06-24024 June 1999 Forwards RAI Re 990111 Request for Relief from Certain ASME Code ISI Requirements for Containment Liners.Response Requested within 30 Days from Date of Agreement IR 05000483/19990041999-06-18018 June 1999 Refers to GL 96-05 Issued by NRC on 960918,UE Responses & 970313 & NRC Insp Rept 50-483/99-04,dtd 990427. Forwards Request for Addl Info Re GL 96-05 Program at Callaway Plant,Unit 1 ML20207H3751999-06-14014 June 1999 Discusses 990407 Une Request That Proprietary Version of Document Entitled, Evaluation of Severe Accident Simulation, Dtd April 1999,be Withheld from Public Disclosure.Determined Info Proprietary & Will Be Withheld ML20195H0971999-06-14014 June 1999 Discusses Une 990407 Request That Proprietary Document Entitled, Thermal Stability Assessment - Electrosleeved Tubes, Be Withheld from Public Disclosure.Determined Info to Be Proprietary & Will Be Withheld from Public Disclosure ML20207G3151999-06-0707 June 1999 Ack Receipt of Callaway Plant EP Implementing Procedure EIP-ZZ-001001M,Classification of Emergencies,Rev 22,issued on 981222 Under 10CFR50,App E,Section V Provisions.No Violations Identified ML20207G3201999-06-0707 June 1999 Ack Receipt of Change Notice 98-008 Dtd 980918,which Transmitted Changes to Callaway Plant Ep,Rev 21,under Provisions of 10CFR50,App E,Section V.No NRC Approval Required.No Violations Identified ML20207E2711999-05-25025 May 1999 Ack Receipt of in Response to & Insp Rept Confirming Commitment as Stated by M Taylor During Telephonic Exit Meeting on 990413 ML20207A8711999-05-24024 May 1999 Informs That NRR Reorganized,Effective 990328.Forwards Organization Chart ML20207A4131999-05-19019 May 1999 Forwards Insp Rept 50-483/99-03 on 990321-0501.One Violation of NRC Requirements Identified & Being Treated as Noncited Violation,Consistent with App C of Enforcement Policy ML20206K6511999-05-10010 May 1999 Forwards RAI Re GL 96-06, Assurance of Equipment Operability & Containment Integrity During Design-Basis Accident Conditions ML20206N3981999-05-10010 May 1999 Responds to Comments & Questions Submitted to NRC Staff Re Recent License Amend Issued by NRC to Callaway Unit 1 License.Provides Context for Conclusion That Reracking of Callaway SFP Maintains Adequate Protection of Public Safety ML20206H1101999-05-0606 May 1999 Forwards Results of Gfes of Written Operator Licensing Exam, Administered on 990407,to Nominated Employees of Facility. Requests That Training Dept Forward Individual Answer Sheets & Results to Appropriate Individuals.Without Encl ML20206H1821999-05-0606 May 1999 Forwards RAI Re Licensee Request for Relief from Certain ASME Code ISI Requirements Submitted by .Response Requested within 30 Days of Receipt of Ltr ML20206F4931999-05-0303 May 1999 Forwards Exam Rept 50-483/99-302 on 990416.Insp Included Evaluation of Applicant for Reactor Operator License ML20205S2571999-04-19019 April 1999 Discusses Plans to Sponsor Testing of Electrosleeved Tubes to Better Understand Behavior of Electrosleeve Matl Under Severe Accident Conditions ML20205Q5461999-04-19019 April 1999 Forwards Safety Evaluation Relief Request from Certain ASME Section XI Requirements for Concrete Containment ISI for Plant ISI Program ML20205K7641999-04-0808 April 1999 Ack Receipt of Re Comments & Questions Concerning Recent Amend to Plant,Unit 1.Response to Comments & Questions Should Be Completed by mid-May ML20205J8701999-04-0606 April 1999 Ack Receipt of ,In Response to NRC Insp Rept 50-483/99-02,dtd 990225 Re Verbal Commitment Made During Exit Meeting for Insp.Understands Next Rev of Security Plan Will Include Increased Min Staffing of Three Armed Guards ML20205J8721999-04-0505 April 1999 Refers to Meeting Conducted in Emergency Operations Facility at Callaway Plant on 990401 Re Plant Performance Review for Plant Completed on 990211.Year 2000 Readiness Issues & New Reactor Licensee Performance Assessment Also Discussed ML20205J9401999-04-0505 April 1999 Forwards Insp Rept 50-483/99-01 on 990207-0330.One Violation Occurred & Being Treated as Noncited Violation,Consistent with App C of Enforcement Policy IR 05000019/20250011999-04-0202 April 1999 Informs That Version of Topical Rept BAW-10219P,Rev 3 Dtd Oct 1998 & Document 51-5001925-01,dtd 980828 Will Be Marked as Proprietary & Be Withheld from Public Disclosure Pursuant to 10CFR2.790(b)(5) & Section 103(b) of Atomic Energy Act ML20205A3821999-03-19019 March 1999 Advises of NRC Planned Insp Effort Resulting from Callaway Plant Performance Review for Period 970510-990125. Historical Listing of Plant Issues & Details of NRC Insp Plan for Next 8 Months Encl ML20204E7281999-03-18018 March 1999 Ack Receipt of Which Transmitted Rev 28 to Callaway Plant Physical Security Plan,Per 10CFR50.54(p).No NRC Approval Is Required,Since Util Determined Changes Do Not Decrease Effectiveness of Plan ML20204E3671999-03-18018 March 1999 Informs That During 990128 Telcon Between D Lantz & H Bundy, Arrangements Were Made for Administration of Retake Written Operator Licensing Exam at Plant,During Wk of 990419 ML20204B7091999-03-15015 March 1999 Informs That Changes Described in ,Submitting Rev 20 to Plant Operational QA Manual,Appear Consistent with Guidelines for non-reduction in Committments ML20204C4241999-03-15015 March 1999 Forwards Request for Addl Info Re GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves ML20207F4731999-03-0404 March 1999 Discusses 990302 Public Meeting Re Program Updates & Organizational Changes in Emergency Preparedness & Security. List of Attendees & Licensee Presentation Encl ML20207L6491999-03-0404 March 1999 Informs That Util 990111 Response to Request for Addl Info Re Question 4 Will Be Marked as Proprietary & Will Be Withheld from Public Disclosure Pursuant to 10CFR2.709(b)(5) & Section 103(b) of Atomic Energy Act of 1954,as Amended 1999-09-22
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Docket Nos.: 50-483 Mr. D. F. Schnell Vice President - Nuclear l Union Electric Company Post Office Box 149 St. Louis, Missouri 63166
Dear Mr. Schnell:
SUBJECT:
ANTICIPATED TRANSIENTS WITHOUT SCRAM - CALLAWAY NUCLEAR PLANT The Nuclear Regulatory Comission (NRC) staff has completed its review of the Westinghouse Owners' Group (W0G) Topical Report WCAP-10858 "AMSAC Generic Design Package" submitted in response to 10 CFR 50.62 " Requirements for Re-duction of Risk from Anticipated Transient Without Scram (ATWS) Events for Light-Water-Cooled Nuclear Power Plants." Guidance for meeting the require-ments of 10 CFR 50.62 was provided in the preamble to that rule and was further provided to all licensees in Generic Letter 85-06 " Quality Assurance Guidance for ATWS Equipment That is Not Safety Related."
The results of the staff's review of the generic design for the ATWS mitiga-tion system actuation circuitry (AMSAC) are contained in the attached Safety Evaluation (SE). The staff has concluded that the generic design is acceptable; however, many plant specific details needed in order to ensure confonnance with the rule are not addressed by the WOG generic design. These details needed by the NRC to complete the review are defined in the SE.
We request that you review the SE and provide, within 30 days of receipt of this letter, your schedules for addressing the plant specific design features discussed in Appendix A of the SE, and for implementation following the staff's approval of your plant specific design.
This request for information is covered under OMB clearance number 3150-0011 which expires September 30, 1986.
If you have any question 5, please cantact ne at (301) 492-7330.
Sincerely,
\Y Paul O'Connor, Project Manager PWR Project Directorate #4 Division of PWR Licensing-A
Enclosure:
As Stated cc: See next page DISTRIBUTION: See next page PWR#4/DPWR- PW M PWR-A PWR#4/DPWR-A P0'Connor/mac c BJYogggblood 09/ M /86 09/},an/86 09/ IJ/86 8609250427 860922 3 DR ADOCK 0500
N Mr. D. F. Schnell Callaway Plant
. Union Electric Company Unit No. 1
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CC:
Mr. Nicholas A. Petrick Lewis C. Green, Esq. .
Executive Director - SNUDPS Green, Hennings & Henry 5 Choke Cherry Road Attorney for Joint Intervenors Rockville, Maryland 20850 314 N. Broadway, Suite 1830 St. Louis, Missouri 65251 Gerald Charnoff, Esq.
Thomas A. Baxter, Esq. Ms. Marjorie Reilly Shaw, Pittman, Potts & Trowbridge Energy Chairman of the League of 1800 M Street, N. W. Women Voters of Univ. City, M0 Washington, D. C. 20036 7065 Pershing Avenue University City, Missouri 63130 Mr. J. E. Birk Assistant to the General Counsel Mr. Donald Bollinger, Member Union Electric Company Missourians for Safe Energy Post Office Box 149 6267 Delmar Boulevard St. Louis, Missouri 63166 University City, Missouri 63130 U. S. Nuclear Regulatory Comission Mr. Dan I. Bolef, President Resident Inspectors Office Kay Drey, Representative RR#1 Board of Directors Coalition Steedman, Missouri 65077 for the Environment St. Louis Region Mr. Donald W. Capone, Manager 6267 Delmar Boulevard Nuclear Engineering University City, Missouri 63130 Union Electric Company Post Office Box 149 St. Louis, Missouri 63166 Chris R. Rogers, P.E.
Manager - Electric Department 301 W. High Post Office Box 360 Jefferson City, Missouri 65102 Regional Administrator U. S. NRC, Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137 Mr. Ronald A. Kucera, Deputy Director Department of Natural Resources P. O. Box 176 Jefferson City, Missouri 65102 Mr. Glenn L. Koester Vice President - Nuclear Kansas Gas and Electric Company 201 North Market Street Post Office Box 208 Wichita, Kansas 67201
SAFETY EVALUATION OF TOPICAL REPORT (WCAP-10858)
, "AM5AC GENERIC DESIGN PACKAGE"
1.0 INTRODUCTION
In response to 10 CFR 50.62 " Requirements for Reduction of Risk-fmm Anticipated Transients Without Scram (ATWS) Events for Light-Water-Cooled Nuclear' Power Plants",
Westinghouse on behalf of the Westinghouse Owner's Group (WOG) has submitted for review WCAP-10858 "AMSAC Generic Design Package." This document details the WOG's proposed generic ATWS Mitigation System Actuation Circuitry (AMSAC) designs for compliance with 10 CFR 50.62.
2.0 BACKGROUND
On July 26, 1984 the Code of Federal Regulations (CFR) was amended to include Section 10 CFR 50.62, " Requirements for Reduction of Risk from Anticipated Transients Without Scram (ATWS) Events for Light-Water-Cooled Nuclear Power Plants" (known as the "ATWS Rule"). An ATWS is an expected operational transient (such as loss of feedwater, loss of condenser vacuum, or loss of offsite power) which is accompanied by a failure of the reactor trip system (RTS) to shut down the reactor.
The ATWS rule ree fres specific improvements in the design and operation of com-mercial nuclear power facilities to reduce the likelihood of failure to shut down the reactor following anticipated transients, and to mitigate the consequences of an ATWS event.
3.0 CRITERIA The basic requirement for Westinghouse plants is specified in paragraph (c)(1) of 10 CFR 50.62, "Each pressurized water reactor must have equipment from sensor output to final actuation device, that is diverse from the' reactor trip system, 4c.o H + o y yo- '
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.2 e to automatically initiate the auxiliary (or emergency) feedwater sys, tem and ini-tiate a turbine trip under conditions indicative of an ATWS. This equipment must be designed to perform its function in a reliable manner and be independent (from sensor output to the final actuation devic ~e) from the existing reactor trip system."
The criteria used in evaluating the Westinghouse report include; (1) 10 CFR 50.62, (2) guidance and infomation published as the preamble to that Rule, and (3)
Generic Letter 85-06 " Quality Assurance Guidance for ATWS Equipment that is not Safety-Rel ated. " The evaluation was done on 0 generic basis, and the relevant criteria is presented below.
The systems and equipment required by 10 CFR 50.62 do not have to meet all of the stringent requirements nomally applied to safety-related equipment. However,,
this equipment is part of the broader class of structures, systems, and com-i ponents defined in the introduction to 10 CFR 50, Appendix A (General Design Criteria).
GDC-1 requires that " structures, systems, and components important to safety shall be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions to be performed." Generic Letter 85-06
" Quality Guidance for ATWS Equipment that is not Safety-Related" details the quality assurance that must be applied to this equipment.
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In general, the equipment to be installed in accordance with the 'ATWS rule is required to be diverse from the existing RTS, and must be testable at power.
This equipment is intended to provide needed diversity (where only minimal diversity currently exists) to reduce the potential for common mode failures that could result in an ATWS leading to unacceptable plant conditions.
The ATWS mitigation design is not required to be safety-related (e.g., meet IEEE-279). However, the implementation should incorporate good engineering practice and must be such that the existing protection system continues to meet all applicable safety related criteria. Equipment diversity to the extent reasonable and practicable to minimize the potential for common cause failures is required from the sensors to, but not including the final actuation device.
All mitigating system instrument channel components (excluding sensors and isola-tion devices) must be diverse from the existing RTS. It is desirable, but not required, to use sensors and isolation devices that are not part of the RTS.
The basis for not requiring diverse isolators is that the RTS unavailability and AMSAC availability (without a reactor trip signal) are similar with or without the addition of a diverse isolator. Furthermore, with the addition of a new component (e.g., the diverse isolator) within AMSAC, the probability of not get-ting a reactor trip signal or AMSAC signal will be increased somewhat by the additional failure rate of the diverse isolator. However, if existing RTS sen-sors and isolators are utilized, particular emphasis should be placed on the method (s) used to qualify the isolators for their particular function. This l
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4
.e should include an analysis and tests which will demonstrate that the existing
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isolator will function under the maximum worst case fault conditions. The required method for qualifying the isolators is presented in Appendix A.
The capability for test and surveillance at power is required, however, sur-veillance frequencies have not been established at this time. During surveil-lance at power, the mitigating system may be bypassed, however, the bypass condi-tion must be automatically and continuously indicated in the main control room.
The AMSAC sy. stem design may also permit bypass of the mitigating function to allow for maintenance, repair, test, or calibration to prevent inadvertent actua-tion of the protective action at the system level. Where operating requirements necessitate automatic or manual bypass of a mitigating system, the design should be such that the bypass will be removed automatically whenever permissive conditions are not met.
The use of a maintenance bypass should not involve lifting leads, pulling fuses or tripping breakers or physically blocking relays. A permanently installed by-pass switch or similar device should be used.
The design should be such that once the ATWS mitigation system has been initiated, the protective action at the system level shall ~go to completion. Return to operation should require subsequent deliberate operator action.
Manual initiation capability of the mitigating systems at the system level is desirable but not required. Manual initiation should depend upon the operation l
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e of a minimum of equipment. The mitigating system should be designed to provide the operator with accurate, complete and timely information per,tinent to its own status. .
Displays and controls for manual bypass and initiation of the mitigating system should be integrated into the main control room through system functional ana-lysis and should conform to good human engineering practices in design and layout. It is important that the displays and controls added to the control room as a result of the ATWS rule not increase the potential for operator error.
A human factor' analysis should be performed taking into consideration:
(a) the use of this information and equipment by an operator during both norwal and abnormal plant conditions, (b) integration into emergency procedures, (c) integration into operator training, and (d) the presence of other alarms during an emergency and need for prioritization of alarms.
The power supplies are not required to be safety-related but they must be capable of performing safety functions with a loss of offsite power, Logic power must be from an instrument power supply independent from the power supplies for the existing reactor trip system. Existing RTS sensor and instrument channel power O
c supplies may be used only if the possibility of common mode failure is prevented.
The most severe ATWS scenarios were determined (see NUREG-0460 Appendix IV. WCAP-8330 and subsequent Westinghouse submittals) to be those in which there was a complete loss of normal feedwater. These included:
Loss of Normal Feedwater/ATWS Transient (LONF/ATWS) .
A complete loss of normal feedwater occurs which results from a malfunction in the feedwater condensate system or its control system from such causes as the simultaneous trip of all condensate pumps, the simultaneous trip of all main feedwater pumps or the simultaneous closure of all main feedwater control,' pump discharge or block valves.
Because of a postulated common mode failure in the RPS, the reactor is incapable of being automatically tripped when any of several plant pro-cess variables have reached their reactor trip setpoints.
Loss of Load /ATWS Transient (LOL/ATWS)
The most severe plant conditions that could result from a loss of load occur following a turbine trip from full power when the turbine l trip is caused by a loss of main condenser vacuum. Because of a common mode failure in the protection system, the reactor is incapable of being automatically tripped as a result of the turbine trip or as the result of any of several other reactor trip signals that occur later in time when several plant process variables reach their reactor trip setpoints.
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e Upon loss of the main condenser vacuum, the main feedwater turbine-driven pumps that exhaust into the main condenser are tripped, th'ereby cutting off feedwater flow to the steam generators. Not all nuclear plants are subject to this transient since rany plants have motor-driven main feedwater pumps or they have turbine-driven pumps which do not exhaust into the main con-denser. Since there is a complete loss of norwal feedwater during both these transients (LONF/ATWS and LOL/ATWS), both transients assumed auxiliary feedwater (AFW) flow is started 60 seconds after the initiating event for long term. reactor protection. Also the Complete Loss of Normal Feedwater transient assumed a turbine trip 30 seconds after the initiating event to maintain short term RCS pressures below 3200 psig. Normally these features would be actuated by the Reactor Protection System (RPS) and the Engineered Safety Features Actuation System (ESFAS).
The primary safety concern from these two transients is the potential for high pressure within the RCS.
If a common mode failure in the RPS and the ESFAS incapacitates AFW flow initiation and/or turbine trip in addition to prohibiting a scram, then an alternate method of providing AFW flow and a turbine trip is required to maintain the RCS pressure below 3200 psig.
The final rule which was approved by the Commissioners on November 11, 1983, requires that Westinghouse designed plants install ATWS Mitigating System Actuation Circuitry (AMSAC) to initiate a turbine trip and actuate AFW flow independent of the RPS (from the sensor output). These two functions, turbine trip and AFW flow actuation, are provided via the AMSAC. .
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4.0 DESIGN DESCRIPTION The Westinghouse Owners Group (WOG) has developed generic designs to meet the requirements of 10 CFR 50.62. Three designs were developed which permits each utility to select the design which best fits a particular plant's needs. Factors that may determine the design utilized at a plant range from the current control and protection system design to the ease and cost of installation. The three designs are as follows:
The first design would actuate a turbine trip and auxiliary feedwater flow upon sensing that the steam generator inventory is below the low-low level setpoint.
This logic senses conditions indicative of an ATWS event when a loss of heat sink has occurred but will not actuate until after the reactor protection signals should have been generated. A turbine trip and start-up of all auxiliary feedwater pumps will occur upon receipt of an AMSAC signal.
The steam generator blowdown isolation and sample isolation valves would be
- automatically closed in all loops when AMSAC is actuated.
The AMSAC signal will be generated by low water level signals in the steam gen-erators using existing sensor / transmitter units. For two loop plants AMSAC will use two channels per loop with 3/4 coincidence to actuate AMSAC. The AMSAC coin-cidence logic for three loop plants is 2/3 with one channel per steam generator and the four loop plants coincidence logic is 3/4 with one channel per steam 9enerator. .
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-g-c The AMSAC signal will be automatically blocked below 70% power since short term protection against high reactor coolant system pressure is not required until 70% of nominal power. This will prevent spurious AMSAC actuation during start-up. To ensure that AMSAC remains armed long enough to perform its function in the event of a turbine trip, a C-20 permissive signal will be maintained for approximately 60 seconds. The AMSAC signal will be delayed by approximately 25 seconds to permit the RPS to respond first.
The second design mitigates the consequences of an ATWS loss of heat sink event by initiating AMSAC on low main feedwater finw measurements.
Actuation of AMSAC will occur on low main feedwater flow as measured by existing main feedwater flow sensor / transmitters. The setpoint to actuate AMSAC is 50%
of nominal main feedwater flow. Although 50% flow is more than ample to protect against overpressure in the event of an ATWS, instrumentation error would become unacceptably large if a substantially lower setpoint were used.
. To avoid inadvertent AMSAC actuation on the loss of one main feedwater pump, AMSAC actuation will be delayed approximately 25 seconds to permit the unfaulted main feedwater pump (s) to automatically increase the flow rate to above the AMSAC actuation setpoint. Recovery in this circumstance is possible since each main feedwater pump is capable of delivering typically 60% of full load capacity.
A turbine trip and start-up of all auxiliary feedwater pumps will occur upon receipt of an AMSAC signal. The steam generator blowdown isolation and sample O
e isolation valves should be automatically closed in all loops when AMSAC is actuated. ' ~
The AMSAC signal will be generated by low main feedwater flow to the steam i generators. The AHSAC logic is two channels per loop with 3/4 coincidence l logic for two loop plants; one channel per loop with 2/3 coincidence logic for three loop plants; and 3/4 ceincidence logic for four loop plants.
i As in the first design, the AMSAC signal will be automatically blocked below 70% power; the AMSAC signal will be delayed by 25 seconds; removal of the C-20 permissive signal will be delayed by approximately 60 seconds.
The third design determines that conditions indicative of an ATWS event are present by monitoring the feedwater control and isolation valves and the feedwater pump status.
Actuation of AMSAC will occur when it has been determined that all main feedwater pumps have been tripped or when main feedwater flow to the steam generators has been blocked due to valve closures.
Failures in the main feedwater system upstream of the main feedwater pumps that could result in the loss of main feedwater to the steam generators, e.g., trip-ping of all condensate pumps, will result in automatic main feedwater pump trips on low suction pressure. Therefore, explicit actuation of AMSAC based on fail-ures of components. upstream of the main feedwater pumps is not necessary.
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. e l Since AMSAC anticipates the plant response due to the loss of main feedwater pumps prior to the reactor protection system detecting an anticipated operational oc-currence, it is desirable to delay AMSAC actuation. A 30 second delay is suffi-cient to allow the reactor protection system to respond.
Either of two different AMSAC concepts may be used, depending upon whether or not the main feedwater flow to the steam generators is split during normal power operation. Plants which contain D-4 and D-5 steam generators have split flow during normal power operation. All other plants do not, although all plants with preheaters will have a minimal bypass flow through the feedwater bypass temper-ingvalve(FBTV). For preheater plants which have split flow during normal power operation, approximately 10 to 20% of the total feedwater flow is passed through the feedwater preheater bypass valves (FPBV), while most of the remaining flow is passed through the feedwater isolation valve (FIV). If all FIVs were to close simultaneously, the flow through the FPBV would increase substantially and still provide protection against RCS overpressurization in the event of an ATWS.
Therefore the accidental closure of~all FIVs is not a factor for plants which contain D-4 or D-5 steam generators. All other plants however must account for the accidental closure of all FIVs as well as the accidental closure of all feed-water control valves (FCVs) and the accidental tripping of all main feedwater pumps.
A turbine trip and start-up of all auxiliary feedwater pumps will occur upon receipt of an AMSAC signal. The steam generator blowdown isolation and sample 1
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isolation valves should be automatically closed in all loops when AMSAC is actuated.
The AMSAC signal will be generated by the simultaneous tripping of all main feedwater pumps or the blocking of all main feedwater lines to the steam gen-erators due to valve malfunctions. The AMSAC coincidence logic it as follows:
Coincidence FW Valves FW Pumps Loops Closed Tripped 2
3/4 N/N 3
2/3 N/N 4
3/4 N/N where N is the number of main feedwater pumps.
As in the first two designs, the AMSAC signal will be automatically blocked below 70% power and the removal of the C-20 permissive signal shall be delayed by ap-proximately 60 seconds.
5.0 CONCLUSION
Generic The staff has reviewed the Westinghouse Topical Report WCAP-10858, "AMSAC Gen-eric Design Package" and has concluded that the generic designs presented in WCAP-10858 adequately meet the requirements of 10 CFR 50.62 and follow the review guidelines that have been discussed previously.
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Plant specific -
WCAP-10858 presents a generic design, however many details and interfaces are of a plant specific nature. The staff will review the implementation of plant spe-cific designs to evaluate compliance with ATWS rule requirements. Key elements of the plant specific design reviews are denoted below.
o Diversity The plant specific submittal should indicate the degree of diversity that exists between the AMSAC equipment and the existing Reactor Protection System. Equipment diversity to the extent reasonable and practicable to minimize the potential for common cause failures is required from the sen-sors output to, but not including, the final actuation device, e.g., exist-ing circuit breakers may be used for the auxiliary feedwater initiation.
The sensors need not be of a diverse design or manufacture. Existing protection system instrument-sensing lines, sensors, and sensor power supplies may be used. Sensor and instrument sensing lines should be selected such that adverse interactions with existing control systems are avoided. ,
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o Logic power supplies . -
The plant specific submittal should discuss the logic power supply design.
According to the rule, the AMSAC logic power supply is not required to be safety-related (Class IE). However, logic power should be from an instrument power supply that is independent from the reactor protec-tion system (RPS) power supplies. Our review of additional information submitted by WOG indicated that power to the logic circuits will utilize RPS batteries and inverters. The staff finds this portion of the design unacceptable, therefore, independent power supplies should be provided, o Safety-related interface i
The plant specific submittal should show that the implementation is such that the existing protection system continues to meet all applicable safety criteria.
o Quality assurance The plant specific submittal should provide information regarding com-pliance with Generic Letter 85-06, " Quality Assurance Guidance for ATWS Equipment that is not Safety-Related."
o Maintenance bypasses The plant specific submittal should discuss how maintenance at power is accomplished and how good human factors engineering practice is incorporated into the continuous indication of bypass status in the control room.
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o Operating bypasses The plant specific submittal should state that operating bypasses are continuously indica'ted in the control room;' provide the basis for the 70% or plant specific operating bypass level; discuss the human factors design aspects of the continuous indication; and discuss the diversity and independence of the C-20 pemissive signal (Defeats the block of AMSAC).
I o 'Means for bypassing The plant specific submittal should state that the means for bypassing is accomplished with a pennanently installed, human factored, bypass switch or similar device, and verify that disallowed methods mentioned in the guidance are not utilized.
o Manual initiation The plant specific submittal should discuss how a manual turbine trip and auxiliary feedwater actuation are accomplished by the operator.
1 o Electrical independence from existing reactor protection system The plant specific submittal should show that electrical independence is achieved. This is required from the sensor output to the final actuation device at which point non-safety-related circuits must be isolated from safety related circuits by qualified Class IE isolators. Use of existing isolators is acceptable. However, each plant specific submittal should pro-vide an analysis and tests which demonstrates that the existing isolator will a
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e function under the maximum worst case fault conditions. The required
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method for qualifying either the existing or diverse isolators is presented in Appendix A.
o Physical separation from existing reactor protection system Physical separation from existing reactor protection system is not required, unless redundant divisions and channels in the existing reactor trip system are not physically separated. The implementation must be such that separa-tion criteria applied to the existing protection system are not violated.
The plant specific submittal should respond to this concern.
o Environmental qualification The plant specific submittal should address the environmental qualification of ATWS equipment for anticipated operational occurrences only, not for accidents, o Testability at power Measures are to be established to test, as appropriate, non safety related ATWS equipment prior to installation and periodically. Testing of AMSAC may be performed with AMSAC in bypass. Testing of AMSAC outputs through the final actuation devices will be performed with the plant shutdown.
The plant specific submittals should present the test program and state that the output signal is indicated in the control room in a manner con-sistent with plant practices including human factors.
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'T o Completion of mitigative action - -
AMSAC shall be designed so that, once actuated, the completion of mitigating action shall be consistent with the plant turbine trip and auxiliary feed-water circuitry. Plant specific submittals should verify that the pro-tective action, once initiated, goes to completion, and that the subsequent return to operation requires deliberate operator action.
o Technical specifications Technical specification requirements related to AMSAC will have to be addressed by plant specific submittals.
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, APPENDIX A AMSAC ISOLATION DEVICE -
REQUEST FOR ADDITIONAL INFORMATION Each light water cooled nuclear reactor shall be provided with a system for the mitigation of the effects from anticipated transients without scram (ATWS). The Comission approved requirements for the ATWS are defined in the*~ Code of Federal Regulations (CFR) Section 10, paragraph 50.62.
The staff has reviewed the Westinghouse Owner's Group generic functional AMSAC designs for compliance with the ATWS Rule. As a result, the staff has deter-mined that the use of isolators within AMSAC will be reviewed on a plant specific basis. The following additional information is required to continue and com-plete the plant specific isolator review:
Isolation Devices Please provide the following:
- a. For the type of device used to accomplish electrical isolation, describe the specific testing performed to demonstrate that the device is acceptable for its application (s). This description should include elementary diagrams when necessary to indicate the test configuration and how the maximum credible faults were applied to the devices.
- b. Data to verify that the maximum credible faults applied during the test were the maximum voltage / current to which the device could be exposed, and de-fine how the maximum voltage / current was determined,
- c. Data to verify that the maximum credible fault was applied to the output of the device in the transverse mode (between signal and return) and other faults were considered (i.e., open and short circuits). l
- d. Define the pass / fail acceptance criteria for each type of device,
- e. Provide a comitment that the isolation devices comply with the environ- '
ment qualifications (10 CFR 50.49) and with the seismic qualifications which were the basis for plant licensing.
- f. Provide a description of the measures taken to protect the safety systems from electrical interference (i.e., Electrostatic Coupling EMI, Comon Mode and Crosstalk) that may be generated by the ATWS circuits.
- g. Provide information to verify that the Class IE isolator is powered from a Class IE source.
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