|
---|
Category:CORRESPONDENCE-LETTERS
MONTHYEARML20217C1051999-10-0808 October 1999 Forwards Amend 153 to License DPR-3 & Safety Evaluation. Amend Revises TS Section 6.0,Administrative Controls,By Deleting TS Sections 6.2.2.f Which Contains Limits on Working Hours of Plant Staff ML20212J2231999-10-0101 October 1999 Forwards Copy of Environ Assessment & Fonsi Re 990317 Application for Amend to Revise TS Section 6.0 by Deleting TS Section 6.2.2.f Which Contains Limits on Working Hours of Plant Staff ML20211J5001999-08-31031 August 1999 Forwards Proposed Rev 29 to Yankee Decomissioning QA Program, for NRC Info & Approval.Yaec Requests That Rev 29, Dtd May 1999 & Originally Transmitted in Be Withdrawn from Further Consideration by NRC Staff ML20211J2711999-08-27027 August 1999 Forwards Amend 152 to License DPR-3 & Safety Evaluation. Amend in Response to Application Dated 990324,deletes License Condition 2.C (10) Which States: Licensee Shall Maintain FFD Program IAW Requirements of 10CFR26 ML20216F1891999-08-26026 August 1999 Forwards Copies of Maine Yankee & Yankee Rowe Refs Listed, Supporting Industry Position That Branch Technical Position Asb 9-2 Methodology over-estimates Spent Fuel Decay Heat ML20210S0621999-08-10010 August 1999 Forwards semi-annual fitness-for-duty Program Performance Data for six-month Period of 990101-990630,IAW 10CFR26.71(d) ML20210R1421999-08-0404 August 1999 Forwards Insp Rept 50-029/99-02 on 990411-0714.One Severity Level 4 Violation Occurred,Being Treated as NCV ML20210F3691999-07-21021 July 1999 Submits Response to NRC Request for Clarification of Certain Details of Yaec Proposed Mods to Yankee Nuclear Power Station Defueled TS ML20209D4881999-07-0909 July 1999 Forwards Rev 29 to Decommissioning QA Program, for Info & NRC Approval,Iaw 10CFR50.54(a)(3).Attachment a Provides Listing of Changes,But Does Not Discuss All Refomatting, Grammatical,Editorial or Typographical Changes ML20209C3271999-07-0101 July 1999 Forwards Rev 2 to Security Training & Qualification Plan.Rev Withheld ML20209C3151999-07-0101 July 1999 Forwards Rev 9 to Security Plan,Reflecting Plant Decommissioning Activities & Continues to Provide Protection Against Radiological Sabotage.Rev Withheld ML20209D1611999-06-28028 June 1999 Forwards UFSAR for Ynps.Updated Ynps FSAR Is Being Submitted Biennially,Iaw Commitment in Ltr Dtd 950614.Document Reflects Changes Made to Ynps as of 981231,unless Otherwise Noted 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 ML20195D6781999-06-0707 June 1999 Forwards Original & Two Copies of New England Coalition on Nuclear Pollution & Consolidated Intervenor Opposition to Yankee Atomic Electric Co Motion to Terminate,As Required by Rule for Filing ML20207E6301999-06-0101 June 1999 Informs of Relocation of Yaec Corporate Ofcs,Effective 990501.New Address Submitted.All Formal NRC Correspondence to Util Should Be Directed to Duke Engineering & Svcs, Marlborough,Ma ML20207D7991999-05-29029 May 1999 Forwards Original & Two Copies of Ltr to ASLB Chairman in Matter of Yankee Nuclear Power Station Proceeding.With Certificate of Svc ML20207D8181999-05-29029 May 1999 Requests That Board Convey to Panel That within Period of Time Authorized by NRC Regulations Author Intends to File, on Behalf of Intervenors,Responsive Pleading to Yaec Pending Motion to Withdraw in Ref Matter.With Certificate of Svc ML20207D8131999-05-27027 May 1999 Discusses Reorganization of Nrr,Effective 990328.Forwards Organizational Chart ML20195B3491999-05-25025 May 1999 Submits Withdrawal of Proposed License Amend to Approve Plant Termination Plan.New Application Will Be Submitted in Future ML20206Q1881999-05-17017 May 1999 Forwards for Filing,Necnp Request for Permission to File Contentions & Contentions on Inadequacy of NRC Staff 990412 Environ Assessment & Finding of No Significant Impact of Approval of Util Termination Plan.With Certificate of Svc ML20206H8701999-05-0505 May 1999 Informs That DB Katz Unable to Locate Copy of Attachments to Which Zobler Referred to in Response to Block Ltr.Requests Info on How Panel Will View Receipt of Ea.With Certificate of Svc ML20206R3221999-05-0505 May 1999 Forwards Insp Rept 50-029/99-01 on 990101-0411.No Violations Noted.Activities at Rowe Facility Generally Characterized by safety-conscious Operations to Maintain Spent Nuclear Fuel & Careful Radiological Controls to Workers ML20206D1801999-04-30030 April 1999 Forwards Citizens Awareness Network First Set of Interrogatories,Requests to Produce & Certificate of Svc. Requests Any Objections Be Submitted Withing Five Days of Filing Receipt.Without Encls.Related Correspondence BVY-99-031, Forwards Ynps Annual Radiological Environ Operating Rept for Jan-Dec 1998, IAW Plant Defueled TS 6.8.2.a1999-04-26026 April 1999 Forwards Ynps Annual Radiological Environ Operating Rept for Jan-Dec 1998, IAW Plant Defueled TS 6.8.2.a ML20206B6641999-04-24024 April 1999 Requests Board Take Action to Remedy NRC Failure to Comply with Board Request & NRC Counsel Representation to Board in Relation to That Request Re Serving EA Upon Petitioners Per Request of Board.With Certificate of Svc ML20206C0801999-04-23023 April 1999 Requests That Change Proposed in Request for Transfer of Administrative Requirements for Ynps Defueled TS to Plant Decommissioning QA Program Be Withdrawn 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 ML20205S0131999-04-17017 April 1999 Forwards Original & Two Conformed Copies of Necnp First Set of Interrogatories & Requests to Produce for Filing in Matter Re Yaec License Termination Plan.Related Correspondence ML20205L0701999-04-13013 April 1999 Grants Voluntary Extension to Allow CAN to Effectively Participate in Hearing Process (ASLBP 98-736-01-LA-R).With Certificate of Svc.Served on 990413 ML20205P9091999-04-13013 April 1999 Informs That Item Intended to Be Attached to 990412 Filing (Motion for Leave to Reply(Reconsideration of Portion of of Prehearing Conference Order)) Inadvertently Overlooked. Section 4, Final Radiation Survey Plan Encl ML20205P2191999-04-12012 April 1999 Informs That Mj Watkins Has Been Appointed to Position as Yankee Rowe Decommissioning Licensing Manager,Effective 990412.Individual Will Serve as Primary Point of Contact for All Info Flow Between NRC & Yaec ML20205K9361999-04-0808 April 1999 Informs That J Block,T Dignan & D Katz Came to Agreement to Extend Discovery in Yankee Rowe License Termination Plan Hearing Process (ASLBP 98-736-01-LA-R) by 1 Wk from 990611 Until 990618 ML20205G7791999-03-31031 March 1999 Provides Info Re Status of Decommissioning Funding for Yankee Power Station,Per 10CFR50.75(f) 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 ML20205F6331999-03-29029 March 1999 Forwards Effluent & Waste Disposal Semi-Annual Rept, for Third & Fourth Quarters of 1998.Rept Summarizes Quantities & Estimated Dose Commitments of Radioactive Liquid & Gaseous Effluents Released During 1998 ML20205N1531999-03-24024 March 1999 Submits Request to Elminate fitness-for-duty Requirement from Plant.Proposed Change Has Been Reviewed by PORC & Nuclear Safety Audit & Review Committee ML20204E5051999-03-17017 March 1999 Requests NRC Review & Approval of Listed Mods to App a of Plant Possession Only License DPR-3 ML20207F8791999-03-0505 March 1999 Forwards Amend 151 to License DPR-3 & Safety Evaluation. Amend Revises Pol by Changing Submittal Interval for Radioactive Effluent Repts from Semiannual to Annual ML20207H8981999-03-0303 March 1999 Responds to Concerns Raised in Petitions to Intervene Filed with NRC by Necnp on 980224 & Citizens Awareness Network on 980226.Petitioners Requested Hearing on NRC Staff Consideration of License Termination Plan for Yankee Plant ML20203G2391999-02-12012 February 1999 Forwards Corrected Index Page for Amend 150 Issued to License DPR-3 on 990203 ML20202H5741999-02-0303 February 1999 Forwards Amend 150 to License DPR-3 & Safety Evaluation. Amend Revises Possession Only License Through Three Changes to TS ML20202F1921999-01-28028 January 1999 Forwards Copy of EA & Fonsi Re Application for Amend to Yaec Pol for Ynps Dtd 980820.Proposed Amend Would Revise Pol Through Listed Changes to TS ML20202E9401999-01-25025 January 1999 Submits Correction to Encl Request for Leave to Make Oral Appearance Statement, .Date of Conference & Desire to Make Oral Appearance Were Inadvertently & Incorrectly Entered on 990127 Instead of 990126 ML20199L1811999-01-22022 January 1999 Requests Opportunity for Representative of EPA to Make Oral Limited Appearance Statement & Submit Written Comments During 990126 Prehearing Conference Re Licensee Termination Plan ML20199K9151999-01-21021 January 1999 Requests Leave to Make Oral Limited Appearance Statement at 990127 Prehearing Conference Re License Termination Plan,Per 981130 Order Concerning Change in Filing Schedules & Date of Prehearing Conference ML20198N1691998-12-30030 December 1998 Forwards Motion for Leave to Participate in Matter of Yankee Atomic Electric Co License Termination Plan ML20198S1661998-12-17017 December 1998 Final Response to FOIA Request for Documents.Records Encl & Identified in App C & D.App E Records Withheld in Part & App F Records Withheld in Entirety (Ref FOIA Exemption 5) & App G Records Withheld in Entirety (Ref FOIA Exemptions 4 & 5) ML20154P9431998-10-16016 October 1998 Forwards Rev 28 to Yankee Atomic Electric Co Decommissioning QA Program. Program Name Changed Due to Status of Plant.Plant in Final Stages of Decommissioning ML20154F0861998-10-0101 October 1998 Forwards Insp Rept 50-029/98-03 on 980601-0731.No Violations Noted ML20153D7271998-09-23023 September 1998 Informs of Changes Made in Personnel Staff at Yankee Nuclear Power Station 1999-08-04
[Table view] Category:INCOMING CORRESPONDENCE
MONTHYEARML20211J5001999-08-31031 August 1999 Forwards Proposed Rev 29 to Yankee Decomissioning QA Program, for NRC Info & Approval.Yaec Requests That Rev 29, Dtd May 1999 & Originally Transmitted in Be Withdrawn from Further Consideration by NRC Staff ML20216F1891999-08-26026 August 1999 Forwards Copies of Maine Yankee & Yankee Rowe Refs Listed, Supporting Industry Position That Branch Technical Position Asb 9-2 Methodology over-estimates Spent Fuel Decay Heat ML20210S0621999-08-10010 August 1999 Forwards semi-annual fitness-for-duty Program Performance Data for six-month Period of 990101-990630,IAW 10CFR26.71(d) ML20210F3691999-07-21021 July 1999 Submits Response to NRC Request for Clarification of Certain Details of Yaec Proposed Mods to Yankee Nuclear Power Station Defueled TS ML20209D4881999-07-0909 July 1999 Forwards Rev 29 to Decommissioning QA Program, for Info & NRC Approval,Iaw 10CFR50.54(a)(3).Attachment a Provides Listing of Changes,But Does Not Discuss All Refomatting, Grammatical,Editorial or Typographical Changes ML20209C3271999-07-0101 July 1999 Forwards Rev 2 to Security Training & Qualification Plan.Rev Withheld ML20209C3151999-07-0101 July 1999 Forwards Rev 9 to Security Plan,Reflecting Plant Decommissioning Activities & Continues to Provide Protection Against Radiological Sabotage.Rev Withheld ML20209D1611999-06-28028 June 1999 Forwards UFSAR for Ynps.Updated Ynps FSAR Is Being Submitted Biennially,Iaw Commitment in Ltr Dtd 950614.Document Reflects Changes Made to Ynps as of 981231,unless Otherwise Noted 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 ML20195D6781999-06-0707 June 1999 Forwards Original & Two Copies of New England Coalition on Nuclear Pollution & Consolidated Intervenor Opposition to Yankee Atomic Electric Co Motion to Terminate,As Required by Rule for Filing ML20207E6301999-06-0101 June 1999 Informs of Relocation of Yaec Corporate Ofcs,Effective 990501.New Address Submitted.All Formal NRC Correspondence to Util Should Be Directed to Duke Engineering & Svcs, Marlborough,Ma ML20207D7991999-05-29029 May 1999 Forwards Original & Two Copies of Ltr to ASLB Chairman in Matter of Yankee Nuclear Power Station Proceeding.With Certificate of Svc ML20207D8181999-05-29029 May 1999 Requests That Board Convey to Panel That within Period of Time Authorized by NRC Regulations Author Intends to File, on Behalf of Intervenors,Responsive Pleading to Yaec Pending Motion to Withdraw in Ref Matter.With Certificate of Svc ML20195B3491999-05-25025 May 1999 Submits Withdrawal of Proposed License Amend to Approve Plant Termination Plan.New Application Will Be Submitted in Future ML20206Q1881999-05-17017 May 1999 Forwards for Filing,Necnp Request for Permission to File Contentions & Contentions on Inadequacy of NRC Staff 990412 Environ Assessment & Finding of No Significant Impact of Approval of Util Termination Plan.With Certificate of Svc ML20206H8701999-05-0505 May 1999 Informs That DB Katz Unable to Locate Copy of Attachments to Which Zobler Referred to in Response to Block Ltr.Requests Info on How Panel Will View Receipt of Ea.With Certificate of Svc BVY-99-031, Forwards Ynps Annual Radiological Environ Operating Rept for Jan-Dec 1998, IAW Plant Defueled TS 6.8.2.a1999-04-26026 April 1999 Forwards Ynps Annual Radiological Environ Operating Rept for Jan-Dec 1998, IAW Plant Defueled TS 6.8.2.a ML20206B6641999-04-24024 April 1999 Requests Board Take Action to Remedy NRC Failure to Comply with Board Request & NRC Counsel Representation to Board in Relation to That Request Re Serving EA Upon Petitioners Per Request of Board.With Certificate of Svc ML20206C0801999-04-23023 April 1999 Requests That Change Proposed in Request for Transfer of Administrative Requirements for Ynps Defueled TS to Plant Decommissioning QA Program Be Withdrawn ML20205S0131999-04-17017 April 1999 Forwards Original & Two Conformed Copies of Necnp First Set of Interrogatories & Requests to Produce for Filing in Matter Re Yaec License Termination Plan.Related Correspondence ML20205P9091999-04-13013 April 1999 Informs That Item Intended to Be Attached to 990412 Filing (Motion for Leave to Reply(Reconsideration of Portion of of Prehearing Conference Order)) Inadvertently Overlooked. Section 4, Final Radiation Survey Plan Encl ML20205P2191999-04-12012 April 1999 Informs That Mj Watkins Has Been Appointed to Position as Yankee Rowe Decommissioning Licensing Manager,Effective 990412.Individual Will Serve as Primary Point of Contact for All Info Flow Between NRC & Yaec ML20205K9361999-04-0808 April 1999 Informs That J Block,T Dignan & D Katz Came to Agreement to Extend Discovery in Yankee Rowe License Termination Plan Hearing Process (ASLBP 98-736-01-LA-R) by 1 Wk from 990611 Until 990618 ML20205G7791999-03-31031 March 1999 Provides Info Re Status of Decommissioning Funding for Yankee Power Station,Per 10CFR50.75(f) ML20205F6331999-03-29029 March 1999 Forwards Effluent & Waste Disposal Semi-Annual Rept, for Third & Fourth Quarters of 1998.Rept Summarizes Quantities & Estimated Dose Commitments of Radioactive Liquid & Gaseous Effluents Released During 1998 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 ML20205N1531999-03-24024 March 1999 Submits Request to Elminate fitness-for-duty Requirement from Plant.Proposed Change Has Been Reviewed by PORC & Nuclear Safety Audit & Review Committee ML20204E5051999-03-17017 March 1999 Requests NRC Review & Approval of Listed Mods to App a of Plant Possession Only License DPR-3 ML20202E9401999-01-25025 January 1999 Submits Correction to Encl Request for Leave to Make Oral Appearance Statement, .Date of Conference & Desire to Make Oral Appearance Were Inadvertently & Incorrectly Entered on 990127 Instead of 990126 ML20199L1811999-01-22022 January 1999 Requests Opportunity for Representative of EPA to Make Oral Limited Appearance Statement & Submit Written Comments During 990126 Prehearing Conference Re Licensee Termination Plan ML20199K9151999-01-21021 January 1999 Requests Leave to Make Oral Limited Appearance Statement at 990127 Prehearing Conference Re License Termination Plan,Per 981130 Order Concerning Change in Filing Schedules & Date of Prehearing Conference ML20198N1691998-12-30030 December 1998 Forwards Motion for Leave to Participate in Matter of Yankee Atomic Electric Co License Termination Plan ML20154P9431998-10-16016 October 1998 Forwards Rev 28 to Yankee Atomic Electric Co Decommissioning QA Program. Program Name Changed Due to Status of Plant.Plant in Final Stages of Decommissioning ML20153D7271998-09-23023 September 1998 Informs of Changes Made in Personnel Staff at Yankee Nuclear Power Station ML20238F4861998-08-27027 August 1998 Forwards fitness-for-duty Performance Data Form for Period 980101-980630 ML20217R2421998-05-0707 May 1998 Forwards,For Filing & Service,Original & Two Copies of New England Coalition on Nuclear Pollution,Inc Opposition to Yaec Motions to Strike & for Conditional Leave to Reply. W/Certificate of Svc ML20217R2691998-05-0707 May 1998 Forwards Detailed Minutes of 980429 Meeting,Which Executive Committee Voted to Endorse & Support Application of Franklin Regional Planning Board to Participate Fully Before ASLB ML20217J1731998-04-27027 April 1998 Forwards Yankee Nuclear Power Station,Annual Radiological Environ Operating Rept,Jan-Dec 1997. Rept Summarizes Findings of Radiological Environ Monitoring Program Conducted by Yae in Vicinity ML20237F1321998-04-24024 April 1998 Partially Deleted FOIA Request for Documents of All Communications Between Attorneys for Yankee Atomic Electric Co & Listed Individuals Re Decommissioning of Listed Plants ML20216G6561998-04-14014 April 1998 Responds to 980318 Request for Info Contained in QA Program ML20217N1501998-03-31031 March 1998 Discusses Response to Yankee Atomic Electric Co Answer to Request for Hearing of Franklin Regional Planning Board. W/Certificate of Svc ML20217J6391998-03-30030 March 1998 Forwards Tables That Summarize Quantities of Radioactive Liquid & Gaseous Effluents & Solid Waste Released from Ynps in Rowe,Ma for Third & Fourth Quarters of 1997.ODCM,encl ML20216E8131998-03-26026 March 1998 Submits Clarification Re Alpb 95-736-01-LA Document. W/Certificate of Svc ML20217F5561998-03-25025 March 1998 Forwards Response to Yankee Atomic Electric Co Answer to Petition to Intervene & Request for Hearing of Franklin Regional Planning Board ML20216F0781998-03-13013 March 1998 Forwards Copies of Answers Filed by Yaec to Four Petitions for Leave to Intervene in Listed Matter.Util Answers Were Filed & Served on 980311,before Receiving Copy of Order of ASLB Panel Establishing Board.W/O Encl ML20216H5901998-03-12012 March 1998 Forwards Response of Yankee Atomic Electric Co to Demand for Info ML20217A0701998-03-12012 March 1998 Forwards Manager Response to Demand for Info & Lead Engineer Response to Demand for Info.All Persons on Svc List Will Receive Copies of Redacted Verifications ML20217Q4481998-03-0404 March 1998 Requests,On Behalf of Franklin Regional Planning Board (Frpb) of Franklin County,Ma,That NRC Conduct 10CFR2,Subpart G Hearing on License Termination Plan Filed by Licensee. W/Certificate of Svc ML20203L4281998-03-0404 March 1998 Advises NRC of Proposed Reorganization of Cmpc,Which Will Result in Creation of New Holding Company Structure for Cmpc.Nrc Consent to Any Indirect Transfer of Control of NRC Operating License,Requested ML20203L1551998-02-27027 February 1998 Provides Response to Demand for Info to Yankee Atomic Electric Co & to Duke Engineering & Services,Inc,Re Inadequate Engineering Analyses & Materially Incomplete & Inacurate Info to NRC License 1999-08-31
[Table view] Category:UTILITY TO NRC
MONTHYEARML20059J6681990-09-0707 September 1990 Forwards Operator Licensing Natl Exam Schedule Through FY94, Per Generic Ltr 90-07 ML20059G0411990-09-0707 September 1990 Lists Util Organizational Changes.Ac Kadak Named President & CEO & Jk Thayer Named vice-president,effective 901001 ML20059G0351990-09-0606 September 1990 Advises That Util Intends to Modify Tech Specs Re Emergency Diesel Generator Surveillance Testing.Util Will Continue to Follow Testing Prescribed by Plant Tech Specs Until Such Time as Approval Received ML20059E1081990-08-28028 August 1990 Forwards Revised Diesel Generator Test Plan,Which Includes Addl Commitments Made During 900822 Discussions ML20059B8121990-08-24024 August 1990 Provides fitness-for-duty Program Performance Data for Period Ending 900630 ML20059B3941990-08-17017 August 1990 Advises That Util Performed Automated Ultrasonic Insp of Pressurizer Vessel Cladding Interface at Plant During 1990 Refueling Outage.Results of Insp Continue to Indicate No Evidence of Any Cladding Indication ML20058N0811990-08-0909 August 1990 Request Relief from ASME Section XI Requirements for Low Pressure Surge Tank Cooling Pumps,Per Generic Ltr 89-04 as Result of Review of Facility Inservice Testing Program ML20058L2241990-08-0303 August 1990 Forwards Peer Review of 900705 Reactor Pressure Vessel Evaluation,Prepared by Le Steele.Review Indicates Agreement W/Methodology in Chapter 5 of Evaluation ML20058L2211990-08-0202 August 1990 Forwards Results of PTS Sensitivity Study for Mean Values of Ref Temps for Four Matls in Beltline Region ML20055J2011990-07-27027 July 1990 Provides Steam Generator Insp Results & Advises of Nine Defective Tubes Discovered During Jul 1990 Insp.Complete Results Will Follow within 12 Months,Per Tech Spec 4.4.10.5.b ML20055H6701990-07-25025 July 1990 Forwards Decommissioning Funding Assurance Rept & Certification, Per 10CFR50.75.Rept Includes Certification That Reasonable Assurance Will Be Provided That Funds Will Be Available for Decommissioning ML20055G6961990-07-20020 July 1990 Forwards YAEC-1731, Yankee Nuclear Power Station Core 21 Performance Analysis. Results of Analysis Demonstrate That Plant Performance Well within Acceptable Limits ML20055G6651990-07-20020 July 1990 Responds to NRC Bulletin 90-001, Loss of Fill-Oil in Transmitters Mfg by Rosemount. Model 1153 Series D Transmitters Not Currently in Use at Plant ML20055G6781990-07-19019 July 1990 Forwards, Yankee Plant Small Break LOCA Analysis ML20055G7031990-07-19019 July 1990 Forwards Rev 0 to Yankee Cycle 21 Core Operating Limits Rept. Cycle Scheduled for Startup on 900811 ML20055H8291990-07-16016 July 1990 Forwards Response to Request for Addl Info Re YAEC-1710, Yankee Nuclear Power Station Pilot Evaluation Rept for Plant License Renewal, & YAEC-1727P, Methodology for Identifying Potential Fluid Component Age-Related.. ML20055H0021990-07-16016 July 1990 Forwards Rev 24 to Security Plan.Rev Withheld ML20055E1531990-07-0505 July 1990 Forwards Reactor Pressure Vessel Evaluation Rept, in Response to NRC 900501,07 & 15 Requests for Addl Info. Specific Chapters Re Requests Listed ML20055D0371990-07-0202 July 1990 Responds to 900319 Commitment to Provide Scope & Schedule for Confirmatory Analysis for Steam Generator Overfill Protection by 900702.Scope of Analysis Will Include Identification of Potential Overfill Scenarios ML20058K3601990-06-28028 June 1990 Forwards Addl Info to Support Proposed Change 234,modifying Tech Specs to Incorporate Wording Consistent w/NUREG-0452, STS for Westinghouse PWRs Re Min Discharge Pressure ML20058K3021990-06-27027 June 1990 Provides Addl Info for Proposed Change 227 to License DPR-3. One Addl LPSI Pump Must Be Capable of Being Placed in Operable Status When Utilizing Spec 3.10.6 ML20248G7471989-10-0303 October 1989 Responds to Generic Ltr 89-04, Guidance on Developing Acceptable Inservice Testing Program. Flow Monitoring Will Be Performed on Emergency Feedwater Pumps & Baseline Flow Data Will Be Established Using clamp-on Flow Device ML20248G8241989-10-0202 October 1989 Forwards Rev 19 to YOQAP-I-A, Operational QA Program, Re Organizational & Programmatic Changes to Stated Plants ML20247B7761989-09-0101 September 1989 Forwards Addl Info Re Topical Rept YAEC-1659 on SIMULATE-3 Validation & Verification ML20247B6051989-08-31031 August 1989 Responds to Generic Ltr 89-12, Operator Licensing Exams. Formats for Proposed Operator Licensing Exam & Requalification Exam Schedules Encl ML20247N1521989-07-27027 July 1989 Advises That Util Has No Agreements W/Employees That Contain Restrictive Clauses Re Notifying NRC of Potential Safety Issues,Per V Stello ML20247N1611989-07-24024 July 1989 Informs That Util Intends to Utilize NRC Incident Response Ctr Data Handling Capabilities to Suppl Util Communications W/Nrc.New Communication Link Will Be Implemented During Facility Annual Emergency Exercise Scheduled for 891128 ML20247H7411989-07-21021 July 1989 Provides Addl Info Re Program to Address Concerns in Insp Rept 50-029/89-05 Re Vendor Technical Info Program.Master Inventory of Vendor Technical Manuals,Located at Plant & Engineering Ofcs,Completed ML20247K0721989-07-21021 July 1989 Responds to Generic Ltr 89-08, Erosion/Corrosion Induced Pipe Wall Thinning, Per Guidelines in NUREG-1344.No Significant Pipe Wall Thinning Other than That Attributed to Normal Wear Occurred in Single Phase Piping ML20248C9291989-07-19019 July 1989 Informs That Bl Drawbridge Will Be Replaced by Nn St Laurent as Acting Manager of Operations,Effective on 890724. Tk Henderson Will Become Acting Plant Superintendent ML20246A5861989-06-30030 June 1989 Informs of Implementation of Upgraded Emergency Operating Procedures,Based on Westinghouse Owners Group Emergency Response Guidelines & Util Procedures Generation Package ML20245C8721989-06-24024 June 1989 Forwards Rev 8 to Plant Security Training & Qualification Plan.Changes Reflect Upgrading Firearms Qualification Courses to practical,performance-based,combat-oriented Programs to Survive Lethal Confrontation.Rev Withheld ML20245C8851989-06-24024 June 1989 Forwards Rev 22 to Plant Security Plan.Changes Reflect Required Retention Period for Security Records.Rev Withheld ML20245H3131989-06-23023 June 1989 Forwards RELAP5YA:Computer Program for LWR Sys Thermal- Hydraulic Analysis,Vol 1:Code Description & RELAP5YA: Computer Program...Vol 2:Users Manual & Response to 197 Questions from NRC ML20245F3161989-06-16016 June 1989 Responds to NRC Bulletin 89-001, Failure of Westinghouse Steam Generator Tube Mechanical Plugs. Determination That Westinghouse Mechanical Plugs from Heat Numbers 3279,3513, 3962 & 4523 Not Installed at Plant Noted ML20247Q7791989-06-0101 June 1989 Responds to NRC Bulletin 88-011, Pressurizer Surge Line Thermal Stratification. Util Committed to Addressing All Actions of Bulletin by 910103.Justification for Continued Operation Encl ML20247E7841989-05-24024 May 1989 Forwards Response to NRC Re Violations Noted in Insp Rept 50-029/89-04.Response Withheld (Ref 10CFR2.201) ML20246D6851989-05-0202 May 1989 Forwards Response to NRC Review Questions on Plant Revised Reflood Heat Transfer Model for LOCA Analysis.To Address Recent Change in App K,Blowdown Heat Transfer Logic Modified to Prevent Use of Dougall-Robsenow Correlation ML20245B4981989-04-18018 April 1989 Forwards Printout of Status of Implementation of TMI Action Items,Per NRC 890414 Request ML20244C7591989-04-14014 April 1989 Provides Supplemental Info to Util 890321 Proposed Change 218 to Add Snubber to Pressurizer Drain Piping to Enhance Seismic Capability of Piping ML20244C5521989-04-13013 April 1989 Responds to Station Blackout Rule 10CFR50.63.Review of Existing Battery Capacity Calculations Verifies That Batteries Have Sufficient Capacity to Meet Station Blackout Loads for 1 H ML20244B8101989-04-10010 April 1989 Forwards Inservice Insp Exam Rept for 881113-890117. Form NIS-I as Required by Provisions of ASME Section XI Also Included ML20244C5381989-04-10010 April 1989 Informs That Util Will Not Propose Change to Tech Spec 6.5.2.10,per Discussion.Nuclear Safety & Audit Review Committee Will Now Rept to President of Yankee,Instead of vice-president.Tech Spec Change Unwarranted ML20247Q6421989-03-31031 March 1989 Responds to NRC Re Violations Noted in Insp Rept 50-029/88-22.Corrective Actions:Mod to Original Engineering Design Change & Evaluation of Engineering Deficiency Performed W/Actions Specific to Prevent Recurrence ML20247Q4851989-03-31031 March 1989 Responds to NRC Bulletin 88-010, Nonconforming Molded-Case Circuit Breakers. Util Maintaining Stored Spares for safety-related Applications,Per Criteria for Action Item 7 ML20247B3081989-03-22022 March 1989 Informs of Present Level of Nuclear Property Insurance Coverage for Plant as of 890401.Coverage Carried W/American Nuclear Insurers & Mutual Atomic Energy Reinsurance Pool ML20247A9011989-03-22022 March 1989 Forwards Yankee Atomic Electric Co Annual Rept 1988. Rept Covers 3-yr Period Ending 881231 ML20236D5961989-03-17017 March 1989 Responds to NRC Re Violations Noted in Insp Rept 50-029/88-09.Corrective Actions:Specific Remedial Training Included in Prestartup Training Program Attended by All Licensed Operators & Shift Technical Advisors ML20235Z0571989-03-0707 March 1989 Forwards Proposed Rev 21 to Security Plan.Rev Withheld ML20235V8491989-03-0303 March 1989 Responds to NRC Bulletin 88-011, Pressurizer Surge Line Thermal Stratification. Bulletin Action Item 1a Completed During Last Refueling Outage & No Indication of Piping or Support Degradation Observed.Plant Analysis Being Performed 1990-09-07
[Table view] |
Text
'
YANKEE ATOMIC ELECTRIC COMPANY r.i.vu on.<s,s><2s-s2e, Star Route, Rowe, Massachusetts 01367 I
c
,Yauxes September 23, 1987 FYR 87-96 United States Nuclear Regulatory Commission l Washington, DC 20555 l Attention: Document Control Desk
References:
(a) License No. DPR-3 (Docket No. 50-29)
(b) USNRC Region I Letter to YAEC, dated August 24, 1987
Subject:
Reply to a Notice of Violation (Inspection No. FiO-29 / 07- 10 )
Dear Sir:
This letter is in response to the Notice of Violation resulting from Inspection No. 50-29/87-10 conducted during the period June 15-19, 1987. The Notice of Violation identified two i tems which apparently were rio t conducted in full compliance with NRC requirements. In accordance with Section 2.201 of the NRC's " Rules and Practices", Part 2, Title 10, Code of Federal Regulations, we hereby submit the following information:
Opparent Violation G A. 10 CFR 20.101(a) Iimits the exposure to the skin of the whole body of any individual in a restricted area to 7.5 rems per calendar quarter.
Contrary to the above, on May 30, 1987, a worker at the facility was contaminated with a radioactive " hot particle" and received a dose to the skin of the whole body (1 cm" of the skin of the scalp) of 10.5 rem, raising his cumulative exposure during the second calendar quarter of 1987 to 11 rem.
This is a Severity Level IV violation.
8709300307 G70923 PDR ADOCK 05000029 OI G $
PDR h/ \ \
y l
l
[ '
(
{
FYR 87-96 l
Resoonse l We acknowledge the Notice of Violation as stated and further
( explained in Inspection Report No. 50-29/87-10. Using j calculational methods such as those contained in the computer l code "VARSKIN" and the isotopic data available for the hot l particle, a dose of approximately 10.5 rem to I square l centimeter of the skin of the whole body can be calculated. -
l :
However, it is our opinion that dosimetric evaluations, '
including those for skin dose due to hot particles, should be based on valid measurement techniques whenever possible. {
Calculational techniques should be employed when measurements )
can not be performed. Based on the measurement techniques used, we feel that the measured dose of 6.5 rem is a more accurate estimate of the dose actually received than the calculated estimate of 10.5 rem. In addition to the measurements of dose performed for the subject hot particle, (as discussed in Inspection Report No. 50-29/87-10), further measurement techniques have been developed to validate this measured dose and to assess skin dose due to hot particles.
Attachment A is a summary of the techniques developed by ;the yankee Nuclear Services Division (YNSD) Environmental Laboratory and the results obtained. This attachment is included for your review with the intent of providing conuttuctive data to aid in addressing the significant, industry wide, " hot particle" problem.
I Evaluation The root cause of this event has been attributed to personnel error. Radiation Protection management failed to have adequate evaluation techniques in place to conservatively estimate the dose rate to the skin due to the presence of the hot particle. Extensive decontamination efforts to remove the hot particle, resulting in significant physical effects such as reddening and bleeding of the scalp of the individual, were not effective. It was determined that more radical .
surgical techniques should be performed only by a physician. The dose evaluation techniques in place at the time led to a significant underestimate of the dose rate to the scalp of the individual. Based on this underestimate, the hot particle was allowed to remain on i the scalp of the individual for a period of 75 hours8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br />.
The subsequently calculcted exposure of 10.5 rem is a direct result of the residence time of the hot particle on the individuals scalp. Although this period of time 1 allowed the hot particle to be easily removed on the morning o f 6/2/87, surgical removal at a much earlier time would have avoided the over exposure.
b:
FYR 87-96 II Corrective Actions Which Have Deen Taken And Results Achieve _d This is the first occurrence of this nature. Based on this occurrence, a number of program and procedural changes were developed and implemented. These changes were effective in controlling and minimizing subsequent exposures of personnel to hot particles and were reviewed in Inspection No. 50-29/97-10. Specifically, the following changes were. implemented:
- 1) All protective clothing in use at the time was removed and segregated. New protective clothing was issued.
- 2) Protec tive c lothing used for work in areas with high potential for hot particle contamination, (e.g.
rubber gloves for Shield Tank Cavity work, protective clothing for Steam Generator entries) was discarded after use.
- 3) Two hour stay times were established for work in the Vapor Container. Personnel were then required to f use the whole body contamination monitors prior to returning to work. Exceptions required by the i nature of the work were handled by establishing alternate controls, (e.g. the issue of new protective clothing).
- 4) The protective clothing policy was changed to require removal of protective clothing at the Vapor :
Container exit rather than at the control point.
a
- 5) One hundred percent of all laundered protective clothing was frisked prior to return to service. A limit of i3OOO cpm was established, protective clothing above this limit was segregated and not returned to service.
- 6) Paper coveralls were worn over cloth coveralls for work in the Vapor Container.
- 7) Masslin and sticky tape rolleru were used to survey {
areas to more effectively monitor areas for the presence of ho t par ticles.
O) A portal monitor was set up at the exit from the control point to the radiological control area as an additional check for exceptionally high activity hot particles.
l l
l
l
- l. .
t l.
FYR 87-96 I
- 9) OP-8430, " Personnel Contamination Monitoring and l
Decontamination," was revised to insure that l
regulatory limits would not be exceeded. Actions,
! including transport to an off-site medical facility, I are required prior to approaching a regulatory l limit.
III Corrective Actions Which Will De Taken To Prevent Recurrence l
The corrective actions described above proved to be effective in the prevention of further overexposure due to hot partitles throughout the remainder of the refueling outage.
Specifically, clear procedural guidance is now provided in OP-8430 to both adequately assess dose from hot particles and assure hot particle removal prior to exceeding regulatory limits.
IV The Date That Full Compliance Was Achieved Full compliance was achieved upon institution of adequate dose assessment techniques on June 2, 1987.
The individual's dose of record for the second quarter of 1987 will be changed to reflect a dose to the skin of the whole body of 11.0 rem. In accordance with 10 CFR 20.409(b), the individual will be notified in writing of the change to his dose of record for the second quarter of 1997. This notification will be transmitted prior to September 24, 1987.
Opparent Violation IJ 10 CFR 20.201(b) requires that each licensee make such surveys as may be necessary to comply with all sections of Part 20. As defined in 10 CFR 20.201(a), " survey" means an evaluation of the radiation hazards incident to the pro &:ction, use, release, disposal, or presence of radioactive materials or other sources of radiation under a specific set of conditions.
Contrary to the above, on May 30, 1997, a proper survey (evaluation) of a hot particle located on the skin of the head of an individual was not made to assure compliance with 10 CFR 20.101(a), which limits the radiation exposure to the skin of the whole body in any ca?endar quarter.
Specifically, the initial dose evaluation following identification of the contaminated hot particle was based on
5 FYR 87-96 an inappropriate assumption concerning the size of the contaminant, in that the contaminant was of smaller dimensions than assumed in the initial assessment. As a result, the initial dose rate estimate (8 mrem /hr) was in error. Subsequent calculations indicated a dose rate of greater than 100 mrem /hr.
This is a Severity Level IV violation.
Response
We concur with the Notice of Violation as described above, in that a proper survey was not performed to an'equately assess dose to the skin.
I Evaluation The root cause of this event has been attributed to personnel error. As was described in Apparent Violation A, Radiation Protection management failed to have adequate evaluation techniques in place to conservatively estimate the dose rate to the skin due to the presence of a hot particle. The failure to perform an adequate survey was a direct result of using the guidance in place at the time in OP-8430, " Personnel Contamination Monitoring and Decontamination." Although we were aware that the contaminant was a point source, (hot particle), initial dose calculations effectively treated the hot particle as a plane source by including the active area of the radiation detector, (15 cm"), in the denominator of the equation used. A more thorough technical review of the draft industry document used as the basis for OP-8430 would have identified a misapplication of the equations presented for skin dose calculations.
II Corrective Actions Which Have Deen Taken And Results Achieved Upon removal of the hot particle from the scalp of the individual, a quantitative isotopic analysis was performed. Using this data, the inadequacy of the l initial dose estimate was identified. The following corrective actions were implemented to immediately establish an adequate dose assessment methodology:
l I
, 1) A computer code nimilar to "VARSKIN" was obtained l from another facility and dose conversion factors for all isotopes of interest were tabulated. An i
adequate method for dose assessment of subsequent hot particle contaminations was available as of l l
l 1700, June 2, 1987.
1 1
l l~
I l l l
! I
_ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ . _ _ ~
FYR 87-96
- 2) With the assistance of the YNSD Environmental Laboratory, the computer code "VARSKIN" was obtained and made available for use.
- 3) OP-8430 was revised to include: >
a) A conservative dose conversion factor for dose assessment of hot particles with G-M Frickers.
b) Action levels requiring isotopic analysis. f '
)
c) Tabulated dose conversion factors for applicable isotopes.
d) The use of the computer code "VARSKIN".
- 4) Gamma spectroscopy systems were calibrated to measure both hot particles removed from the skin and hot particles still on an individual.
- 5) The hot particle was transported to the YNSD Environmental Laboratory for confirmatory gamma l isotopic analysis and further evaluation.
- 6) A hot particle of similar isotopic composition was transported to the YNSD Environmental Laboratory for
"'Sr, 'oSr-Y measurements. Using the data obtained, methods to estimate a'Sr,
- Sr-Y activity based on the activity of various gamma emitting isotopes were developed. This methodology was available for use f on June 15, 1987 and included in a subsequent revision to OP-0430 which was PORC approved July 9, 1907.
III Corrective Actions Which Will De Taken To Prevent Recurrence The corrective actions described above were effective in quickly implementing adequate survey techniques for hot particle contaminations. Although refinements to the program will continue to be made, an adequate hot particle program is currently in place.
IV ]lle Date That Full Compliance Was Achieved Full compliance was achieved on June 2, 1987 when i adequate survey techniques for hot particle contaminations were established.
) !
l l
I
.____________.J
i FYR 87-96
{
i If you have any questions or desire additional i n fo rma t io n , l please contact us.
Sincerely, H. Heider k Vice President and Mgr. of Operations cc: [1] Region I -
021 Resident Inspector i
l
)
)
)
)
1-
)
l l l
l 1
f
)
}
}
) I
, ATTACHMENT A REFERENCES
- 1. Memorandum to R.A. Mellor from N. Stanford, " Final Report and Evaluation of Yankee Plant Hot Particle", dated June 10, 1987 EL 355/87.
- 2. " Design and Operation of an Extrapolation Chamber with Removable Electrodes" by R. Loevinger and W. G. Trott, International Journal of Applied Radiation and Isotopes, 1966, Vol. 17, pp. 103-111.
- 3. "Use of a Victcrian 500 Electrometer to Determine Ionization Chamber Collection Ef ficiencies", by P. R. Almond, Medical physics Journal, Vol. B. No. 6, Nov./Dec., 1981.
- 4. Memorandum from R. A. Mellor to C. M. Babineau, " Independent Estimation of Sr-89 and Sr-90 Concentrations in the 5/30/87 Scalp particle", dated June 15, 1987, CH 057/87.
- 5. " Mathematical Theory of Radiation Dosimetry", by J.J. Fitzgerald, C.L. Brownell and F.J. Mahoney, Gordon and Breach Science Publishers, Inc. New York, NY, copyright 196 7.
- 6. Radiological Decay Data Tables by David C. Kocher, Technical Information Center, U.S. Department of Energy, 1981.
This report presents further research and testing concerning the use of the Vinten extremity dosimeter for direct measurement of skin dose resulting from irradiation by a hot particle. The two concerns which were raised in NRC inspection report #50-29/87-10 concerning this technique have been addressed.
The areas of concern are: 1) the accuracy of the dosimeter effective area value and 2) the ef fect of the underresponse of the dosimeter to low energy beta radiation. In addition, data is presented from a definitive comparison between this technique, the VARSKIN computer code and extrapolation chamber measurements of a hot particle similar in composition to the originally measured particle. The results of this comparison show the Vinten dosimeter measurement to provide excellent agreement with the extrapolation chamber while the VARSKIN model overestimates the dose significantly.
. Effective Area The standard Vinten extremity dosimeter has a 5 mg/cm2 layer of phosphor over an area of 0.6 cm x 1.0 cm or 0.6 cm2 Due to the limiting dimensions of the plate on which the dosimeter is mounted for processing and the co111mation of the photomultiplier tube (Figure 1), the actual area of phosphor over which thermoluminescence is gathered is calculated to be 0.29 cm2 As the estimated dose to 1 cm2 is very sensitive to this parameter, an experiment was devised to verify this calculated value.
To verify the maximum effective area of the dosimeter, Vinten ins t rument s . LTD was requested to manufacture a batch of dosimeters with phosphor areas of varying lengths. In addition to the normal 1.0 cm length, groups were manuf actured at .8, .7, .6 and .5 cm lengths. All five groups of
dosimeters were manufcetured f rom the s:me batch of phosphor so that c comparison of sensitivities would indicate the depsndence of asnsitivity en length. The smaller dosimeters were expected to produce a reduced signal compared to the full size batch only when their length became the limiting dimension, i.e. when the length of the phosphor approached the diameter of the collimator. Figure 2 contains illustrations of the relative dimensions with the calculated ureas of interest indicated. The ratio of the response of any ,
given dosimeter length to that of the standard 1 cm length was expected to be i equal to the ratio of the esiculated effective areas for equal delivered {
dose.
Ten dosimeters from each of the five groups of test TLDs were exposed to a uniform field of 137 sC gamma radiation. All of the dosimeters were processed following normal protocol, centering the phosphor area over the l opening of the mounting plate. The responses of the dosimeters, corrected for background using unieradiated dosimeters of the same group, were averaged for l each group. The average group responses were then divided by the average l response for the standard I cm batch. The results, which are presented in l i Table 1, indicate excellent agreement between the observed ratio of responses i l and the ratio of the calculated effective areas, supporting the technique for calculating the effective phosphor area.
l l
TABLE 1 OBSERVED VERSUS PREDICTED RATIOS OF THE RESP 0NSE OF DIFFERENT LENGTH DOSIMETERS l
Calculat ed Ratio of Effective Effective Area Observed Ratio of Area to 1.0 cm Dosimeter response to 1.0 cm 2
Length (cm) (cm ) Effective Area Dosimeter Response 1.0 1 .01 .289 - - . --
1 0.8 1 .01 .289 1.00 1.02 1 .09 0.7 1 .01 .289 1.00 1.00 1 .09 0.6 1 .01 .280 0.97 0.97 1 .08 0.5 1 .01 .247 0.85 0.85 1 .07 Re.syonse to Low Energy Beta Radiation An estimate of the underresponse of the dosimeter due to low energy beta i radiation of 20 percent was quoted in the NRC inspection report. This number, l which was felt to be somewhat conservative, was checked by the DSC using e l more rigorous method.
In order to evaluate the expected underresponse of the Vinten dosimeters, l Loevinger's expression (Ref erence 5) was employed to calculate the apparent absorption coefficient based on the end point energies (Reference 6) of the 2
2
_ individual beto partic1cs emittsd by tha isotep) involv26. Th2 me n value ;
theor n w;s uccd to cvar ss th2 Gxpon:ntial ettsnuaticn of cich bato antrgy over the 5 as em-2 thickness of the Vinten dosimeter. The fractional yield of the beta energy and the fraction of the total dose delivered to 1 cm2 aren under 7 mg em-2, based on the VARSKIN code, was used to weight the i effect of the individual underresponses. The summation of these individual ')
underresponses yicided an estimated overall underresponse of approximately 10 i percent.
Comparison with Extrapolation Chamber i
To further test the accuracy of this method of measurins skin dose from a )
hot particle, a comparison was made with extrapolation chamber measurements, j The Yankee Plant staff obtained a second hot particle (actually three 1 discernable particles, each measuring approximately 200 ym and contained in !
an area of less than 2mm) of suf ficiently high activity to allow precise extrapolation chamber measurements using a 3 cm2 collecting electrode.
]
The particic/(' logged as "STC UPNH Sump , Speck") was held on a piece of umsking tape which' was in turn covered by a layer of 0.8 mg/cm2 clear mylar j film. This configuration was used for both dosimeter irradiations and j extrapolation chamber measurements. I I
The radionuclides composition of this second hot particle was evaluated using gamma ray spectroscopy and,found to be similar to the origins 1 particle, validating a comparison of dosimeter performance. The relative abundance of the major constituents of each particle, as determined with gamma ray l analysis, are tabulated below.
l I
l l
l l
l l
3 l
l i L___________ !
1 TABLE 2 COMPOSITION OF ORIGINAL AND WEW HOT PARTICLE
% of Total Activity Radionuclides Original Wew 95Z r 16 16 95Nb 21 23 144Ce 11 16 144Pr il 16 141Ce 11 7 103Ru 8 6 140La 5 <1 140Ba 4 <1 l
106Ru 2 1 l l
106Eh 2 1 l
1311 1 ..
l 137Cs 1 1 I 89sr 7 10 90S r 1 2 .
l 90Y 1 2 pos.'eter Measurements l
Vinten dosimeters were used for dose measurements using the same techniques that were outlined for the original particle in June of 1987 ,
(Reference 1). The particle was placed on top of the five dosimeter configuration (Figure 3) snd left in contact with the center dosimeter for a measured time period. The four noncentral dosimeters were then used to calculate the dose delivered to the 1 cm2 area, outside of the 0.29 cm2 effective area of the central dosimeter. The five replicate irradiations using this configuration resulted in an average dose rate estimate of 46.31 6.0 rad /hr.
4 I
t
, Extrapolation Chamber Measurements On July 31, 1987 the YAEL extrapolation chamber was used to determine the absorbed dose rate at 7.0 mg em-2 Six layers of 0.86 mg em-2 aluminized mylar were placed between the previously described particle configuration and the window of the extrapolation chamber. The weight of the plexiglass sheet was allowed to bear down upon the mylar sheets to avoid any air gaps between the sheets. This arrangement yielded a 6.9 mg cm-2 density thickness between the particle and the active volume of the extrapolation chamber.
The extrapolation chamber was equipped with a special electrode having an j l
active area of I cm2, manufactured specifically for these measurements. The !
l electrode is a one inch thick 4 cm radius lucite cylinder coated with a fine layer of colloidal graphite. A thin (11/1000 inch) groove was etched through the graphite into the lucite to isolate a 0.564 cm (1 cm2) circle from the outer annulus. The machining of the electrode's active area was verified using the capacitance techniques outlined in Reference 2 to be well within ,
1 percent of I cm2 The particle was centered over the active volume by !
moving the particle across the window until the ionization current reading on the electrometer was maximized.
l This positioning technique was repeated i several times and the maximum current verified. plate spacings of 0.1 mm l increments were used to minimize any geometrical effects associated with a changing active volume. The ionization collection efficiency for each plate l separation was determined to be at least 99.7 percent using the methodologies l of Reference 3. An extrapolation, which was performed between 0.8 and 0.4 nn, yielded an absorbed dose rate of 46.5 1 0.86 rad /hr based on a least squares fit to the measurement data. This measurement was performed in accordance l with YAEL Procedure 950 and the data is maintained in data file E8721113.
I VARSK1W Analysis on "STC UNR Sump Speck" The samma spectroscopy analysis performed at the Yankee plant was used i for input in the VARSKIN computer program. The results of the gamma analysis and the corresponding VARSKIN dose estimales are contained in Table 3.
5 l
l ,
. TABLE 3 GAMMA AED VARSKlW ANALYSIS OF KTC UNR SUMP SPECK JULY 31, 1987 Absorbed Dose Rate (rem /hr) over Isotope pCi yCi*See (3) I cm2 9 7 sag em- 2
'Nb-95 6.04 2.17 E4 5.2 2r-95 4 04 1.45 E4 19.6 Ru-103 1.52 5.47 E4 3.2 Rh-106 .339 1.22 E3 3.2 l
Ru-106 (1) .339 1.22 E3 0.00 Cs-137 .165 5.92 E2 1.1 La-140 (1) .115 4.14 E2 1.0 1
Ba-140 .100 3.59 E2 0.7 Ce-141 1,82 6.54 E3 10.1 Ce-144 4.07 1.46 E4 13.2 Pr-144 (1) 4.07 1.46 EA 38.2 Sr-89 (2) 2.47 8.90 E3 21.5 Br-90 (2) 0.43 1.54 E3 2.9 1
Y-90 (2) 0.43 1,54 E3 3.9 123.8 f 7.5(4) rem /hr (1) Activity for these isotopes based on activity of associated parent isotope.
(2) Calculated based on core inventories as outlined in Reference 4.
(3) The tirne interval used was 3600 seconds in order for the VARSKIW code to calculate rem /hr.
(4) Total uncertainly in the VARSK1W estimate is based on a propagation of the uncertainty in the counting statistics.
6
The racults cf tha three techniqu2s cra listed belcw. For p:rticiss of
. thir cisa cnd r dionuclida mixtura, th2 techniqua using th2 Vinten desimeter
'has been shown to accurately estimate the skin dose, while the VARSKlW model
_substantially overestimates the dose.
TABLE 4 COMPARISON OF THREE TJCHN1 QUES TO EVALUATE SKIN DOSE FROM A HOT PARTICLE (RESULTS IN RAD /HR) i Extrapolation Vinten Chamber Dosimeter VARSKIN ]j l
46.5 1 0.9 46.3 1 6.0 123.8 1 7.5 i
Summary The work presented in this report verifies the accuracy of direct skin dose measurements of submillimeter radioactive particles using the Vinten j extremity thermoluminescent dosimeter. The actual effective area over which ;
dose is averaged by the dosimeter has been experimentally verified. Most I importantly, the accuracy of this technique has been verified for a particle of mixed fission products using a direct comparison with extrapolation chamber measurements.
i l
l l
l i
1 7
L_________________._ --
FIGURE-1 Relative Dimensions of I cm x 0.6 cm Vinten Extremity Dosimeter, Dosimeter Mounting Plate and Photomultiplier Tube Collimator Photomultiplier Tube Collimator Radius = 0.325 cm
_ /
/ / Dosimeter Plate 7 --- Opening 0.8 cm x 0.5 cm
.__ nosimeter Phosphor r 1 cm x 0.6 cm 2
Area = .289 cm Sc' ale = 10:1 i
l I
w__ _-- -_ _ _ _ _
FIGURE 2 Relativa Dimensions for Tcat Dosin2tsr Crcups Showing Phospbsr l Area Effective Reader Area and Total Effective Dosimeter Area i
/ / > / / ,
/
/ /
/ /
/
\ s i s / /
/ l 0.8 cm x 0.6 cm 2 Effective area = .289 cm
,/ > > s - Scale = 6.5:1 '
\ Area of Collimator
\ and Dosimeter Pla'td
// Area of Dosimeter j ,
[ Phosphor
//s s s _s c 0.7 cm x 0.6 cm Effective area = .289 cm To al Effective
/. / s /
s- s s //
0.6 cm x 0.6 cm 2 Effective Area = .281 cm
// / /
WD . , _
MGURE 3 TOP VIDI - 00$1ETER CONFIGURATION West test Dosimete -
Dosimeter {
Petri Msh i
- ~
- g
' s. 1
/
t
/
i l
-"mi
--- A 7~.--
' ' North l Dosimeter l
-(" ;,p ,,; ::;'I:q ,
I 'a r .!I g < ,
4 l
l n .
$ngg \,
J t ^ ,; "-d' n.c ;" '.','
Dosimeter
( ;;A', ,' , e l: -
$OUrCt
\
\
Central Dosimete
_ _ _ _ _ _ _ _ _ - - - - - - - - -