Similar Documents at Maine Yankee |
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Category:CORRESPONDENCE-LETTERS
MONTHYEARML20217N8371999-10-13013 October 1999 Forwards Summary of Changes Made to Maine Yankee Defueled Security Plan,Iaw 10CFR50.54(p)(2).Without Encl ML20217J0241999-10-13013 October 1999 Documents 991005 Telcon Between NRC & Util to Address All of Areas Identified in Reg Guide 1.179 & NUREG-1700 Re Final Survey Plan Except for One Area ML20212F4321999-09-24024 September 1999 Responds to 990921 e-mail to E Poteat,Requesting Waiver of Late Charges of Listed Amount for Annual Fee Invoice AR0431-99.Request Denied Because 10CFR15.37 Does Not Provide for Waiver Based on Info Provided in e-mail ML20212M2431999-09-22022 September 1999 Expresses Concern Re NRC Consideration of Adoption of Policy Based on Requests from Licensees,To Allow as Part of Decommissioning of Nuclear Power Plants & Demolition of Onsite Structures at Reactor Plant Sites ML20212E4611999-09-20020 September 1999 Responds to Concerning Possible Involvement in Weekly Telephone Calls NRC Staff Has with Maine Yankee Staff ML20212F1361999-09-20020 September 1999 Confirms That NMSS Has Received 990916 Submittal & Will Be Included as Attachment to Commission Paper Along with State of Maine Submittal ML20212F2521999-09-20020 September 1999 Confirms That NMSS Has Received 990916 Submittal & Will Be Included as Attachment to Commission Paper Along with State of Maine Submittal ML20212B7011999-09-14014 September 1999 Submits Comments & Raises Questions Re Generation of White Paper for Commission to Decide Merits of Rubberization ML20212A5911999-09-0808 September 1999 Responds to 990816 e-mail & 990901 Telcon with Respect to Comments Re Decommissioning of Maine Yankee Site.Concerns Raised with Respect to Status of Fuel at Maine Yankee Have Been Raised in Previous Ltrs to Us NRC ML20211M9371999-08-30030 August 1999 Addresses Two Issues Raised in s to Senator Collins & Governor a King That Relate to Construction of ISFSI at Maine Yankee ML20212B2181999-08-30030 August 1999 Responds to Re 990707 Message from N Allen Re Transportation Incident Involving Shipment from Maine Yankee Nuclear Power Plant ML20212E4841999-08-27027 August 1999 Informs That at 990429 Meeting of Myap Community Advisory Panel,R Shadis,Asked If Given Lack of Resident Inspectors & Limited NRC-license Review Correspondence,If Shadis Could Take Part in Weekly NRC Conference Calls with Licensee 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 ML20211C0591999-08-19019 August 1999 Forwards Addl Justification for Proprietary Request Re 990809 Submittal Info on Maine Yankee License Termination Plan ML20212A5981999-08-16016 August 1999 Expresses Appreciation for with Respect to e-mail Message Re Site Release Criteria Standards Can Never Be Verified Using Existing Database ML20211D7041999-08-0909 August 1999 Forwards Rev 17 of Maine Yankee Defueled Safety Analysis Rept (Dsar), Per 10CFR50.71 & 10CFR50.4 ML20217M6501999-08-0909 August 1999 Responds to 990719 E-mail Re Cleanup Stds at MYAPC Station & Verification of Meeting Cleanup Stds.Informs That NRC Criteria for Licensing NPPs Contained in 10CFR50 & That 10CFR50.82 Addresses Requirements for License Termination ML20210Q7201999-08-0909 August 1999 Forwards non-proprietary & Proprietary Draft Documents Re Info on Myap License Termination Plan & Diskette.Proprietary Info & Diskette Withheld ML20212B2271999-08-0606 August 1999 Discusses Concerns Re Recent Incindent Involving Transport of Nuclear Matl from Maine Yankee ML20210M8171999-08-0505 August 1999 Forwards Draft License Termination Plan/Amend Plan for Maine Yankee Atomic Power Co, to Enhance Dialogue Between Various Stakeholders & Provide Springboard for Clarifying Mutual Expectations.With Three Oversize Drawings ML20210L2211999-08-0202 August 1999 Forwards Two Copies of Objectives & Sequence of Events for Maine Yankee Emergency Preparedness Exercise for 990922. Without Encl ML20210G3751999-07-28028 July 1999 Ack Receipt of June 30th Ltr That Responded to EDO Backfit Appeal Determination Re Bdba in Sfps.Staff Completed All Actions Associated with Backfit Appeal & Awaiting for New Info for Consideration Prior to Taking Addl Action ML20216D4311999-07-19019 July 1999 Informs That Util Intends to Construct ISFSI Located on Owner Controlled Property Currently Part of Maine Yankee Reactor Site ML20217M6571999-07-19019 July 1999 Expresses Concern Re Verification of Cleanup Stds at Maine Yankee Atomic Power Co Power Station ML20210C6271999-07-15015 July 1999 Forwards Draft Site Characterization Summary in Support of 10CFR50 License Termination & Copy of Latest Decommissioning Schedule with Milestones Identified.Info Submitted Per License Termination Plan ML20196K4751999-07-0606 July 1999 Informs That Confirmatory Orders ,830314,840614 & 960103 Have Been Rescinded.Staff Determined That Due to Permanently Shutdown & Defueled Status of Facility,Orders No Longer Necessary for Safe Operation & Maint.Se Encl ML20210G3981999-06-30030 June 1999 Discusses Review of Ltr Re Maine Yankee Backfit Appeal with Respect to Emergency Plan Exemptions for Decommissioning Plants ML20209C7731999-06-30030 June 1999 Responds to EDO Backfit Appeal Determination Re Emergency Plan Exemptions for Decommissioning Plants ML20209B4611999-06-29029 June 1999 Submits Response to GL 98-01, Y2K Readiness of Computer Sys at Nuclear Power Plants. Plant Is Y2K Ready.Contingency Plans Developed to Mitigate Potential Impact of non-plant Y2K-induced Events ML20196D9191999-06-22022 June 1999 Informs That NRC Has Completed Review of Issues Raised in of Appeal to NRC Edo.Submits List Summarizing Actions Taken Since 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 ML20207H3371999-06-11011 June 1999 Expresses Appreciation for Participation at 990413 Reactor Decommissioning Public Meeting & Responds to Concern Re Absense of Timeliness on Part of NRC Replying to Letters ML20195G9411999-06-10010 June 1999 Informs That Maine Yankee Considers Backfit Claim & Appeal Request of 980716 & 990316,to Be Acceptably Resolved Based on Staff 990518 Response ML20195F7531999-06-0707 June 1999 Forwards Copy of Insurance Endorsement Dtd 990429,reflecting Change in Nuclear Energy Liability Insurance,Iaw Requirements of 10CFR140.15(e) ML20195F6721999-06-0707 June 1999 Forwards Insp Rept 50-309/99-01 on 990214-0513.No Violations Noted.Operations & Radiological Protection Programs, Including Radioactive Liquid & Gaseous Effluent Control Programs,Were Inspected During Insp ML20206U9711999-05-18018 May 1999 Responds to & Addl Info Re Appeal of NRC Determination Re Claim of Backfit Concerning Permanently Shutdown Reactor Security Plan ML20207A2851999-05-14014 May 1999 Informs That NRC Office of Nuclear Reactor Regulation Reorganized Effective 990328.As Part of Reorganization, Division of Licensing Project Mgt Created.Organization Chart Encl ML20206H1391999-05-0505 May 1999 Forwards Amend 164 to License DPR-36 & Safety Evaluation. Amend Consists of Changes to License in Response to 970930 Application ML20206H2311999-05-0404 May 1999 Responds to to Chairman Jackson.Forwards Copy of Recent Staff Response to Petition Submitted on Behalf of Ucs Re Fuel Cladding at Operational Reactors ML20206G5561999-05-0303 May 1999 Forwards Amend 163 to License DPR-36 & Safety Evaluation. Amend Revises Liquid & Gaseous Release Rate Limits to Reflect Revs to 10CFR20, Stds for Protection Against Radiation ML20206J2801999-04-30030 April 1999 Forwards 1998 Annual Financial Repts for CT Light & Power Co,Western Ma Electric Co,Public Svc Co of Nh,North Atlantic Energy Corp,Northeast Nuclear Energy Co & North Atlantic Energy Svc Corp,License Holders ML20206D7191999-04-29029 April 1999 Forwards Listed Radiological Repts for 1998 Submitted IAW Relevant Portions of License DPR-36 & ODCM ML20206E2911999-04-28028 April 1999 Requests NRC Review of ISFSI Licensing Submittals,As Scheduled & ISFSI Approval for Operation by Dec 2000.Util Will Support Any NRC RAI on Expedited Basis.Licensing Milestone Schedule,Encl ML20206E3101999-04-28028 April 1999 Forwards Data Diskette Containing 1998 Individual Monitoring NRC Form 5 Rept,Per 10CFR20.2206(b).Without Diskette ML20206A5521999-04-23023 April 1999 Forwards Environ Assessment & Finding of No Significant Impact Related to Util Application Dtd 980714,for Amend to License DPR-36 to Revise App a TSs to Change Liquid & Gaseous Release Rate Limits to Reflect Revs Made to 10CFR20 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 ML20205N6211999-04-0707 April 1999 Ack Receipt of Which Appealed NRC Staff Determination That Util Had Not Raised Valid Backfit Claim in to Nrc.Staff Began Process of Convening Backfit Review Panel to Evaluate Appeal ML20205K6541999-04-0707 April 1999 Submits Nuclear Property Insurance Coverage Presently in Force to Protect Maine Yankee at Wiscasset,Me ML20206H2401999-03-30030 March 1999 Informs That Myap Recently Revealed That Approx 20% of Fuel Assemblies Now in SFP Are non-std & Require Special Handling & Dry Cask Packaging.Info Confirms Growing Evidence of Periodic Loss of Radiological Control 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 1999-09-08
[Table view] Category:INCOMING CORRESPONDENCE
MONTHYEARML20217N8371999-10-13013 October 1999 Forwards Summary of Changes Made to Maine Yankee Defueled Security Plan,Iaw 10CFR50.54(p)(2).Without Encl ML20217J0241999-10-13013 October 1999 Documents 991005 Telcon Between NRC & Util to Address All of Areas Identified in Reg Guide 1.179 & NUREG-1700 Re Final Survey Plan Except for One Area ML20212M2431999-09-22022 September 1999 Expresses Concern Re NRC Consideration of Adoption of Policy Based on Requests from Licensees,To Allow as Part of Decommissioning of Nuclear Power Plants & Demolition of Onsite Structures at Reactor Plant Sites ML20212B7011999-09-14014 September 1999 Submits Comments & Raises Questions Re Generation of White Paper for Commission to Decide Merits of Rubberization ML20212E4841999-08-27027 August 1999 Informs That at 990429 Meeting of Myap Community Advisory Panel,R Shadis,Asked If Given Lack of Resident Inspectors & Limited NRC-license Review Correspondence,If Shadis Could Take Part in Weekly NRC Conference Calls with Licensee 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 ML20211C0591999-08-19019 August 1999 Forwards Addl Justification for Proprietary Request Re 990809 Submittal Info on Maine Yankee License Termination Plan ML20212A5981999-08-16016 August 1999 Expresses Appreciation for with Respect to e-mail Message Re Site Release Criteria Standards Can Never Be Verified Using Existing Database ML20210Q7201999-08-0909 August 1999 Forwards non-proprietary & Proprietary Draft Documents Re Info on Myap License Termination Plan & Diskette.Proprietary Info & Diskette Withheld ML20211D7041999-08-0909 August 1999 Forwards Rev 17 of Maine Yankee Defueled Safety Analysis Rept (Dsar), Per 10CFR50.71 & 10CFR50.4 ML20212B2271999-08-0606 August 1999 Discusses Concerns Re Recent Incindent Involving Transport of Nuclear Matl from Maine Yankee ML20210M8171999-08-0505 August 1999 Forwards Draft License Termination Plan/Amend Plan for Maine Yankee Atomic Power Co, to Enhance Dialogue Between Various Stakeholders & Provide Springboard for Clarifying Mutual Expectations.With Three Oversize Drawings ML20210L2211999-08-0202 August 1999 Forwards Two Copies of Objectives & Sequence of Events for Maine Yankee Emergency Preparedness Exercise for 990922. Without Encl ML20217M6571999-07-19019 July 1999 Expresses Concern Re Verification of Cleanup Stds at Maine Yankee Atomic Power Co Power Station ML20216D4311999-07-19019 July 1999 Informs That Util Intends to Construct ISFSI Located on Owner Controlled Property Currently Part of Maine Yankee Reactor Site ML20210C6271999-07-15015 July 1999 Forwards Draft Site Characterization Summary in Support of 10CFR50 License Termination & Copy of Latest Decommissioning Schedule with Milestones Identified.Info Submitted Per License Termination Plan ML20210G3981999-06-30030 June 1999 Discusses Review of Ltr Re Maine Yankee Backfit Appeal with Respect to Emergency Plan Exemptions for Decommissioning Plants ML20209C7731999-06-30030 June 1999 Responds to EDO Backfit Appeal Determination Re Emergency Plan Exemptions for Decommissioning Plants ML20209B4611999-06-29029 June 1999 Submits Response to GL 98-01, Y2K Readiness of Computer Sys at Nuclear Power Plants. Plant Is Y2K Ready.Contingency Plans Developed to Mitigate Potential Impact of non-plant Y2K-induced Events 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 ML20195G9411999-06-10010 June 1999 Informs That Maine Yankee Considers Backfit Claim & Appeal Request of 980716 & 990316,to Be Acceptably Resolved Based on Staff 990518 Response ML20195F7531999-06-0707 June 1999 Forwards Copy of Insurance Endorsement Dtd 990429,reflecting Change in Nuclear Energy Liability Insurance,Iaw Requirements of 10CFR140.15(e) ML20206J2801999-04-30030 April 1999 Forwards 1998 Annual Financial Repts for CT Light & Power Co,Western Ma Electric Co,Public Svc Co of Nh,North Atlantic Energy Corp,Northeast Nuclear Energy Co & North Atlantic Energy Svc Corp,License Holders ML20206D7191999-04-29029 April 1999 Forwards Listed Radiological Repts for 1998 Submitted IAW Relevant Portions of License DPR-36 & ODCM ML20206E2911999-04-28028 April 1999 Requests NRC Review of ISFSI Licensing Submittals,As Scheduled & ISFSI Approval for Operation by Dec 2000.Util Will Support Any NRC RAI on Expedited Basis.Licensing Milestone Schedule,Encl ML20206E3101999-04-28028 April 1999 Forwards Data Diskette Containing 1998 Individual Monitoring NRC Form 5 Rept,Per 10CFR20.2206(b).Without Diskette ML20205K6541999-04-0707 April 1999 Submits Nuclear Property Insurance Coverage Presently in Force to Protect Maine Yankee at Wiscasset,Me ML20206H2401999-03-30030 March 1999 Informs That Myap Recently Revealed That Approx 20% of Fuel Assemblies Now in SFP Are non-std & Require Special Handling & Dry Cask Packaging.Info Confirms Growing Evidence of Periodic Loss of Radiological Control 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 ML20205C3331999-03-24024 March 1999 Submits Rept on Status of Decommissioning Funding for Year Ending 981231.Requested Info Provided in Attachment ML20205B7321999-03-24024 March 1999 Documents Withdrawal of Previously Submitted Request for Exemption from Requirements of 10CFR70.24 Re Criticality Accident Requirements, ML20204E5671999-03-18018 March 1999 Forwards Rev 1 to Maine Yankee Atomic Power Station Security Plan & Description of Changes & Summary of 10CFR50.54(p) Effectiveness Evaluation.Without Encl ML20206K6811999-03-16016 March 1999 Forwards Background & Details Re Backfits Claimed in Util Re Permanently Shutdown Reactor Security Plan ML20205G9841999-01-0505 January 1999 Discusses 1997 Maff - Sepa Radioactivity in Food & Environ ML20197J9001998-12-0707 December 1998 Submits Appeal of DD Re Myap Claim of Backfit Re Beyond Design Basis Accidents in Spent Fuel Pools.Discussion of Licensee Reasons,Provided ML20198J4061998-11-0909 November 1998 Ack Receipt of Roe Response to & Copy of Chairman 981014 address,S-98-25.Informs That Root of NRC Problems Lies in Inability to Create multi-dimensional Vision,Mission or Picture of Future NRC in 2003,2008 or Any Time Frame ML20195E8961998-11-0909 November 1998 Provides Response to Nov, Re NRC Insp Repts 50-309/96-09,50-309/96-10,50-309/96-11,50-309/96-16 & 50-309/97-01.Corrective Actions:Util in Compliance with TS 5.5,which Is Current Ref to Cited TS 5.8.2.a ML20155J0871998-11-0505 November 1998 Forwards Supplemental Info for NRC Review Re TS Change 208 Request on Sf Pool Cooling Sys ML20155H9461998-11-0303 November 1998 Informs That All Future Correspondence Being Sent to Myap Should Be Sent to Listed Address ML20155G9451998-11-0303 November 1998 Forwards Rev 1 to M01-1258-002, Decommissioning Cost Analysis for Myaps, Detailing Study of Decommissioning Costs.Rev 1 to Post-Shutdown Decommissioning Rept, Encl. Info Is Submitted as Required by 10CFR50.82(a)(8)(iii) ML20155D6461998-10-29029 October 1998 Forwards Corrected, Occupational Radiation Exposure Rept for 1997, Including Work & Job Function Categories That Were in Effect in 1997 Under Former TS 5.9.1.3.A.Earlier Submittal Contained Incorrect Info ML20155D7971998-10-28028 October 1998 Forwards Response to NRC 981002 RAI Re Modeling Spent Fuel Pool Heatup.Info Is Needed for NRC to Address Future Exemption Requests from Permanently Shutdown Plants in More Generic & Timely Manner ML20155B7221998-10-26026 October 1998 Informs That Util Has Been Unsuccessful in Determining Status &/Or Estimated Completion Date of NRC Evaluation of Licensee Backfit Claim.Assistance in Resolving Matter, Requested ML20154L4821998-10-15015 October 1998 Forwards Maine Yankee Defueled Emergency Plan. Change to Maine Yankee Emergency Plan Has Been Made in Accordance with 10CFR50.54(q) ML20203H2231998-10-14014 October 1998 FOIA Request for Documents Re EAs 96-299,96-320,96-375, 96-397,97-034,97-147 & 97-559 for Myaps.Requested Documents Include OI Repts & Internal Ltrs,Memos & e-mail Messages to & from OE ML20206N7601998-10-13013 October 1998 Discusses Concerns Re Regulatory Failures at Maine Yankee & Requests NRC Convene Public Meeting Between NRC Staff & Maine Yankee Stakeholders to Discuss Events of Past Two Years ML20203A8291998-09-29029 September 1998 Submits follow-up to Last Week Telcon Request That NRC Meet with Maine Advisory Committee on Radiation on Evening of 991104,to Provide Info & Answer Questions to Committee on Recent Exemptions Granted to Maine Yankee on Emergency Plan ML20153E7541998-09-22022 September 1998 Expresses Disappointment in Quality & Approach of Staff SER, to Provide Comments on Some of Bases Considered in Issuance of Exemption to Allow Util to Discontinue Offsite Emergency Planning Activities.Factual Discrepancies Noted ML20153B2971998-09-17017 September 1998 Withdraws Exemption Request from Certain Insurance Coverage & Financial Protection Requirement Limits of 10CFR50.54(w) & 10CFR140.11.If NRC Disagrees W/Conclusion Contained in Ltr, NRC Should Continue to Process 10CFR140.11 Request ML20155D8331998-08-31031 August 1998 Forwards Public Version of, Maine Yankee Emergency Preparedness Exercise, for Exercise Scheduled for 981028. Rept Demonstrates Major on-site Emergency Response Elements for Defueled & Permanently Defueled Shutdown Plant 1999-09-22
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MaineVankee RELIABLE ELECTRICITY SINCE 1972 329 BATH ROAD = BRUNSWICK, MAINE 04011 + (207) 798-4100 i
' December 3,1996
' MN-96-172 JRH-269 UNITED STATES NUCLEAR REGULATORY COMMISSION Attention: Document Control Desk Washington, D.C. 20555
References:
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a) License no. DPR-36 (Docket No. 50-309) '
b) MYAPCo Letter to USNRC dated June 27,1995 (MN-95-73) .
. c) USNRC Letter to MYAPCo dated October 21,1996
. d) MYAPCo Letter to USNRC dated November 29,1995 (MN-95-132)
Subject:
Response to Generic L'etter 95-03 "Circumferential Cracking of Steam Tubes" Request for i AdditionalInformation 1 Gentlemen:
l This letter provides additional information as requested in Reference (c) and supplements Maine i Yankee's response to Generic Letter 95-03, Reference (b). I NRC_REQUESTEDINEORMATION140ml The following areas have exhibited circumferential cracking:
a) Expansion transition circumferential cracking b) U-bend circumferential cracking c) Dented location (including dented TSP) circumferential cracking d) Sleeve joint circumfeVential cracking-m t- . . z. ;wq ., , ,, , .,
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In your response to Generic Letter (GL) 95-03, the susceptibility of the U-bends and dented locations in your steam generators to circumferential cracking was not addressed. If these areas are susceptible to circumferential cracking, please submit the information requested in GL 95-03 per the guidance contained in the GL for these areas and any other area susceptible to circumferential cracking. The above response should clarify the inspections performed at these locations during the prior tube inspection outage and should clarify the inspections to be performed during the next scheduled steam generator tube inspection. For dented locations, if applicable, the criteria for determining which dents are/were examined should be provided. If a dent voltage threshold is used for such a determination, the calibration procedure used (i.e.,4.0 volts on 4-20 percent through-wall l ASME holes at 550/130 mix) should be provided. i O
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9612110333 961203 f\
V PDR ADOCK 05000309 )
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. . MaineYankee !
l UNITED STATES NUCLEAR REGULATORY COMMISSION MN-96-172 Attention: Document Control Desk Page Two Maine. Yankee Response i
In its latest (1995) steam generator inspections, Maine Yankee inspected 100% of the tightest radius U-bends (tube rows 1 through 12 inclusive) in each ofits three steam generators with a Motorized Rotating Pancake Coil (MRPC). No circumferential cracks were detected. j l
The majority of the Maine Yankee horizontal tube suppons are of steel lattice bar (egg crate) design and steam generator tubes are not prone to circumferential cracking at their intersections. Two i partial drilled plate horizontal supports do exist near the top of the Maine Yankee S/G's. In each of Maine Yankee's 1993 and 1995 steam generator inspections,25 randomly selected dented drilled support plate intersections were examined with an MRPC. No circumferential cracks were detected. l The region of the steam generators containing the tight U-bends and the partial drilled support plates operates at a lower temperature than the hot leg top of tubesheet expansion transitions where circumferential cracking has previously been observed at Maine Yankee and are not thought to be j as susceptible to circumferential cracking. No circumferential cracks have ever been detected m these regions in the Maine Yankee steam generators. i 1
Maine Yankee is presently observing minimum to no primary to secondary leakage in its steam generators. Maine Yankee's low administrative and proposed Technical Specification (Reference l d) steam generator leakage limits of 50 and 150 GPD respectively, should ensure Maine Yankee i shuts down and makes s epairs before the stresr. in any tube exceeds its design criteria. l Because of the lower temperature, no previously detected circumferential cracks, and minimum to l I
no observed primary to secondary leakage presently being observed, Maine Yankee does not believe circumferential cracks of significance are present in the U-bends or at the partial drilled suppon plates of the Maine Yankee steam generators. I In the next scheduled steam generator inspection (Fall 1997), Maine Yankee will repeat the 100%
MRPC examination of the U-bends in rows 1 through 12.
A sample of the partial drilled support plant intersections will be inspected with an MRPC in the 1997 steam generator inspection. The MRPC inspection sample (s) will be defined by the magnitude of denting observed at the intersections in the 1995 bobbin probe exams. Dent data from 1995 is available for all of the partial drilled support intersections. It is desirable to identify the MRPC samples before the 1997 outage to have the flexibility to conduct MRPC inspections with equipment set up in the hot leg channel heads while simultaneously conducting bobbin exams with equipment set up in the cold leg channel heads. Because the magnitude of dents has not been observed to change significantly between recent inspections, the difference in the inspection samples based on either 1995 or 1997 bobbin dent data is expected to be negligible. The 1995 dent calibration was made by setting the 400 Khz absolute voltage at 10.0 volts on a 0.010" radius dent in the ASME calibration standard. One volt was the dent reporting threshold.
- . . MaineYankee l UNITED STATES NUCLEAR REGULATORY COMMISSION MN-96-172 Attention: Document Control Desk Page Three The initial partial drilled support plate MRPC sample will be of the most dented intersections.
Expansion samples (if required) will examine successfully less dented intersections. The hot leg partial drilled support plate MRPC inspection program is as follows:
Initial Sample 20% of dented intersections of 5 volts or larger I
First Expansion Sample (If a Single Circumferential Crack is Observed in the Initial Sample) 100% of dented intersections 5 volts or larger &
20% of dented intersections between 1 and 5 volts Second Expansion Sample (If a Single Circumferential Crack is Observed in the Previous 1 to ;
5 Volt Sample) 100% of dented intersections between 1 and 5 volts &
20% of nondented intersections l
Third Expansion Sample (If a Single Circumferential Crack is Observed in the previous Nondented intersections) 100% of allintersections &
Initiate and expand inspections of the cold leg partial drilled support plates as was done for the hot leg support plates.
NRCREQUESTED.INEORMATION NO.2 In your GL 95-03 response, it was indicated that a 20 percent sample of the sleeves installed during the present outage (i.e.,1995 outage) would be examined in the next outage and that 20 percent of-the cold leg expansion transition regionjust above the top of the tubesheet would be examined with techniques suitable to detect circumferential cracking (e.g., plus point and Cecco 5). In addition, it was indicated that a submittal would be made which addresses the expansion criteria. Please specify the expansion criteria to be used during the next scheduled steam generator tube inspection for these regions (i.e., cold leg expansion transitions and all installed sleeves).
MaineYankee Response If circumferential cracking is detected at the cold leg expansion transition, Maine Yankee will expand the test program to include all cold leg tubesheet transitions in the affected steam generator.
In the event that circumferential cracking is detected in installed sleeves, the expansion criteria will be based on the failure mechanism. If the presence of the crack is associated with the installation process, e.g. sleeves that have been rewelded, reworked, etc., the expansion would be limited to sleeves with this condition. If, however, the presence of the crack is not associated with a unique installation condition, all sleeved tubes will be examined in the affected steam generator.
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. . MaineYankee UNITED STATES NUCLEAR REGULATORY COMMISSION MN-96-172 Attention: Document Control Desk' Page Four NRC_ Requested.InformationNo.3 Discuss whether terrain plots will be used to analyze the RPC eddy current data at locations susceptible to circumferential cracking during your next steam generator tube inspection (i.e., the next inspection per your Generic Letter 95-03 response).
MainelankeeResponse During the 1995 MRPC examination, terrain maps were used for all recorded data. This practice will be continued during the next examination (Fall 1997).
We trust that the above information adequately addresses your questions. Should you have additional questions or require clarification on any of the above, please contact us at your convemence.
Very truly yours, e
James R. Hebert, Manager Licensing & Engineering Support Department CHE/JRH/mwf c: Mr. Hubert Miller Mr. J. T. Yerokun Mr. Daniel H. Dorman Mr. Patrick J. Dostie Mr. Uldis Vanags )
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