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Category:Code Relief or Alternative
MONTHYEARML20099D9552020-04-17017 April 2020 Request to Use Provisions in the 2013 Edition of the ASME Boiler and Pressure Vessel Code for Performing Non-Destructive Examinations ML19269C5342019-09-27027 September 2019 Proposed Alternative to Use Encoded Phased Array Ultrasonic Examination Techniques ML19226A0232019-09-19019 September 2019 Relief from the Requirements of the Asme Code Examination and Testing for Containment Unbonded Post-Tensioning System (EPID-L-2018-LLR-0132) ML19161A2572019-06-0404 June 2019 BWR Fleet Msv/Srv - Testing Frequency Relief Request NRC Pre-Application Meeting June 4, 2019 JAFP-19-0023, Relief Request Associated with the Use of Encoded Phased Array Ultrasonic Examination Techniques in Lieu of Radiography for Ferritic and Austenitic Piping Welds2019-02-15015 February 2019 Relief Request Associated with the Use of Encoded Phased Array Ultrasonic Examination Techniques in Lieu of Radiography for Ferritic and Austenitic Piping Welds JAFP-18-0052, Proposed Alternative to Utilize Code Case N-8792018-05-30030 May 2018 Proposed Alternative to Utilize Code Case N-879 JAFP-18-0053, Proposed Alternative to Utilize Code Cases N-878 and N-8802018-05-30030 May 2018 Proposed Alternative to Utilize Code Cases N-878 and N-880 ML16308A0272017-01-10010 January 2017 Relief from the Requirements of the ASME Code ML15163A2492015-09-15015 September 2015 Relief Request RR-14-01 Concerning Alternative Root Mean Square Depth Sizing Requirements TMI-14-136, Response to Request for Additional Information - Submittal of Relief Request RR-14-01 Concerning Alternative Root Mean Square (Rms) Depth Sizing Requirements2014-11-19019 November 2014 Response to Request for Additional Information - Submittal of Relief Request RR-14-01 Concerning Alternative Root Mean Square (Rms) Depth Sizing Requirements ML13232A0512013-08-28028 August 2013 Relief Request VR-01, Proposed Alternative Testing of the Pressurizer Pilot Operated Relief Valve ML13227A0072013-08-27027 August 2013 End-of-Interval Relief Request RR-12-01, Pressurizer Nozzle-to-Head Weld Examinations ML13227A0242013-08-15015 August 2013 Relief Requests PR-01, PR-02, and VR-02, Associated with the Fifth Ten-Year Inservice Test Interval TMI-12-168, Submittal of Relief Requests Associated with the Fifth Inservice Testing (IST) Interval2012-11-0707 November 2012 Submittal of Relief Requests Associated with the Fifth Inservice Testing (IST) Interval ML12121A6372012-05-10010 May 2012 Request to Use Code Case N-789 ML1117304752011-07-20020 July 2011 Fourth Inservice Inspection Interval Relief Requests I4R-02, I 4R-03, I4R-04, I4R-05, and I4R-06 TMI-11-017, Submittal of Relief Request RR-11-01 and RR-11-022011-02-10010 February 2011 Submittal of Relief Request RR-11-01 and RR-11-02 ML1029303472010-10-21021 October 2010 Acceptance of Requested Licensing Action Request for Relief l4R-02, Fourth Inservice Inspection Interval, Alternate Risk Informed Selection and Examination Criteria for Pressure Retaining Welds ML1026406132010-09-23023 September 2010 Supplemental Information Needed for Acceptance of Requested Licensing Action Request for Relief l4R-02, Fourth Inservice Inspection Interval, Alternate Risk Informed Selection and Examination Criteria for ML0830903882008-10-29029 October 2008 Request for Relief 2008-TMI-01 to Utilize Code Case N-725 ML0527906602005-10-0606 October 2005 Response to Request for Additional Information Request for Relief to Utilize Code Case N-638-1, Similar and Dissimilar Metal Welding Using Ambient Temperature Machine GTAW Temper Bead Technique, Section XI Division 1 ML0416705102004-07-21021 July 2004 (TMI-1) Request for Relief from Flaw Removal, Heat Treatment, and Nondestructive Examination Requirements for the Third 10-Year Inservice Inspection (ISI) Interval ML0416701962004-07-0202 July 2004 (TMI-1) Request for Relief (P5) for the Nuclear Service Closed Cooling Water (Nsccw) Pumps for Third 10-Year Inservice Testing (IST) Interval ML0334305002003-11-25025 November 2003 Additional Information Concerning a Proposed Alternative Associated with the Use of a Weld Overlay ML0333709532003-11-20020 November 2003 Additional Information Concerning a Proposed Alternative with the Use of Weld Overlay ML0335602922003-11-0707 November 2003 Additional Information Concerning a Proposed Alternative Associated with the Use of a Weld Overlay ML0335602942003-11-0303 November 2003 Proposed Alternative Associated with the Use of a Weld Overlay ML0323205482003-09-0505 September 2003 Request for Relief from Selected Aspects of ASME Code. 2020-04-17
[Table view] Category:Letter
MONTHYEARML24038A0222024-02-0505 February 2024 Achp Letter on Section 106 Programmatic Agreement Participation IR 05000289/20230062024-01-29029 January 2024 Constellation Energy Generation, LLC, Three Mile Island Nuclear Station, Unit 1 - NRC Inspection Report No. 05000289/2023006 ML23342A1242024-01-0909 January 2024 Independent Spent Fuel Storage Installation Security Inspection Plan ML23325A1092024-01-0505 January 2024 Review of the Management Plan for Three Mile Island Station, Unit No. 2, Debris Material ML23354A2062023-12-20020 December 2023 (TMI-2), Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation ML23354A2112023-12-20020 December 2023 Response to Request for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5 IR 05000320/20230032023-11-28028 November 2023 TMI-2 Solutions, LLC, Three Mile Island Nuclear Station, Unit 2, NRC Inspection Report No. 05000320/2023003 ML23243A9082023-08-29029 August 2023 Shpo Letter to TMI-2 Regarding Section 106 Activities IR 05000320/20230022023-08-17017 August 2023 TMI-2 Solutions, LLC, Three Mile Island Nuclear Station, Unit 2 - NRC Inspection Report 05000320/2023002 ML23216A1742023-08-14014 August 2023 Consultation Letter to David Morrison for TMI-2 ML23216A1772023-08-14014 August 2023 Consultation Letter to Rebecca Countess for TMI-2 ML23216A1752023-08-14014 August 2023 Consultation Letter to Joanna Cain for TMI-2 ML23216A1732023-08-14014 August 2023 Consultation Letter to Christine Turner for TMI-2 IR 05000289/20230052023-08-14014 August 2023 Constellation Energy Generation, LLC, Three Mile Island Nuclear Station, Unit 1 - NRC Inspection Report 05000289/2023005 ML23216A1782023-08-14014 August 2023 Consultation Letter to Steve Letavic for TMI-2 ML23221A1402023-08-0808 August 2023 (TMI-2), Response to Requests for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5 ML23200A1882023-07-31031 July 2023 TMI-2 Correction Letter Amendment 67 ML23209A7632023-07-28028 July 2023 Letter from PA Shpo to TMI-2 Solutions on Cultural and Historic Impacts of Decommissioning ML23192A8272023-07-10010 July 2023 TMI-2 Solutions, LLC - Response to Shpo Request for Additional Information for Er Project 2021PR03278.006, TMI-2 Decommissioning Project ML23167A4642023-07-0505 July 2023 Letter - TMI-2- Exemption 10 CFR Part 20 Append G Issuance ML23167A0312023-06-28028 June 2023 Acceptance Review and Schedule for the Request for Exemption from a Requirement from 10 CFR 20, Appendix G, Section Iii.E, EPID L-2023-LLE-0016 ML23171B0222023-06-19019 June 2023 (TMI-2) - Notification Pursuant to 10 CFR 72.140(d) Regarding Application of Previously Approved TMI-2 Quality Assurance Program to Independent Spent Fuel Storage Installation Activities ML23137A2822023-05-17017 May 2023 (TMI-2), Request for Exemption from 10 CFR 20, Appendix G, Section Iii.E ML23138A0662023-05-17017 May 2023 TMI-2 NHPA Section 106 Shpo Letter to NRC 5-17-23 ML23026A3132023-05-0202 May 2023 Issuance of Exemption from 10 CFR 70.24 (EPID-L-2023-LLE-0003) ML23122A1842023-05-0101 May 2023 Shpo_Er_Summary_Letter ML23121A2492023-05-0101 May 2023 License Amendment Request, Historic and Cultural Resources Review, Response to Request for Additional Information ML23117A0012023-04-26026 April 2023 Commitment Revision Summary Report ML23027A0832023-04-24024 April 2023 Environmental Assessment/Finding of No Significant Impact - Request for Exemption from 10 CFR 70.24 ML23108A0802023-04-18018 April 2023 Annual Radiological Effluent Release Report ML23108A0822023-04-18018 April 2023 Annual Radiological Environmental Operating Report IR 05000320/20230012023-04-12012 April 2023 TMI-2 Solutions, LLC, Three Mile Island Nuclear Station, Unit 2 - NRC Inspection Report No. 05000320/2023001 ML23102A0382023-04-10010 April 2023 Occupational Radiation Exposure Annual Report ML23108A2002023-04-10010 April 2023 CFR 20.2206(b) Personnel Radiation Exposure Report for 2022 ML23094A2582023-04-0606 April 2023 Letter to Sidney Hill, Chief, Onondaga Nation, Re., Initiation of Consultation Under Section 106 of the NHPA for the Proposed License Amendment Request for TMI 2 ML23093A0572023-04-0606 April 2023 Letter to Joanna Cain, President, Re., Ongoing Activities Related to the Proposed License Amendment Request for Three Mile Island Nuclear Station, Unit 2 ML23094A2362023-04-0606 April 2023 Letter to Carissa Speck, Re., Initiation of Consultation Under Section 106 of the NHPA for the Proposed License Amendment Request for Three Mile Island Nuclear Station, Unit 2 ML23094A2542023-04-0606 April 2023 Ltr J Bendremer Thpo Stockbridge-Munsee Community Band of Mohican Indians Re Initiation of Consultation Under Section 106 of the NHPA for Proposed License Amendment Request for TMI 2 ML23086C0652023-04-0606 April 2023 Ltr Larry Heady, Thpo, De. Tribe of Indian; Re., Initiation of Consultation Under Section 106 of the NHPA for the Proposed License Amendment Request for TMI Nuclear Station, Unit 2 ML23093A0562023-04-0606 April 2023 Letter to Steve Minnick, Site Decommissioning Director, Re., Ongoing Activities Related to the Proposed License Amendment Request for Three Mile Island Nuclear Station, Unit 2 ML23094A2602023-04-0606 April 2023 Letter to William Tarrant, Seneca-Cayuga Nation, Re., Initiation of Consultation Under Section 106 of the NHPA for the Proposed License Amendment Request for TMI 2 ML23094A2392023-04-0606 April 2023 Letter to Courtney Gerzetich, Thpo, Onedia Nation of Wisconsin, Re., Initiation of Consultation Under Section 106 of the NHPA for the Proposed License Amendment Request for TMI 2 ML23093A0592023-04-0606 April 2023 Letter to Rebecca Countess, Chair, Re., Ongoing Activities Related to the Proposed License Amendment Request for Three Mile Island Nuclear Station, Unit 2 2024-02-05
[Table view] Category:Safety Evaluation
MONTHYEARML23094A2692023-04-20020 April 2023 Safety Evaluation - Exemption from 10 CFR 70.24 ML23051A0442023-03-31031 March 2023 Safety Evaluation ML23024A0122023-01-26026 January 2023 Letter to Energysolutions Transmitting Threshold Determination for Merger/Restructuring ML22074A0272022-04-0707 April 2022 TMI 1 ISFSI Emergency Plan Only SER Input ML20297A6272020-12-0404 December 2020 Issuance of Amendment No. 301 Removal of Cyber Security Plan License Condition ML20297A6352020-12-0303 December 2020 Issuance of Amendment No. 300 Deletion of Permanently Defueledt Technical Specification 3/4.1.4, Handling of Irradiated Fuel with Fuel Handling Building Crane ML20261H9252020-12-0202 December 2020 Issuance of Amendment No. 299 for Unit 1 Permanently Defueled Emergency Plan and Emergency Action Level Scheme Changes ML20279A3732020-12-0202 December 2020 Enclosure 3: TMI-2 LTA Safety Evaluation ML20244A2922020-12-0101 December 2020 Exemptions from Certain Emergency Planning Requirements and Related Safety Evaluation ML20134H9402020-07-0808 July 2020 Issuance of Amendments Revising the High Radiation Area Administrative Controls ML20021A0702020-04-0606 April 2020 Issuance of Amendments to Delete License Conditions for Decommissioning Trusts ML20065J4762020-03-11011 March 2020 Safety Evaluation Spent Fuel Management Plan ML19269C5342019-09-27027 September 2019 Proposed Alternative to Use Encoded Phased Array Ultrasonic Examination Techniques ML19226A0232019-09-19019 September 2019 Relief from the Requirements of the Asme Code Examination and Testing for Containment Unbonded Post-Tensioning System (EPID-L-2018-LLR-0132) ML19211D3172019-08-29029 August 2019 Issuance of Amendment No. 297 Defueled Technical Specifications and Revised License Conditions ML19192A2442019-07-18018 July 2019 Proposed Alternative to Use ASME Code Cases N-878 and N-880 ML19065A1142019-04-18018 April 2019 Issuance of Amendment No. 296 for Unit 1 Changes to Emergency Plan for Post-Shutdown and Permanently Defueled Condition ML18305B4192018-12-14014 December 2018 Issuance of Amendment No. 295 Changes to Technical Specifications Sections 1.0, Definitions, and 6.0, Administrative Controls, for Permanently Defueled Condition ML18310A0322018-11-22022 November 2018 Safety Evaluation Input for Proposed Changes to the Three Mile Island Nuclear Station Emergency Plan for Post-Shutdown and Permanently Defueled Condition ML18206A2822018-08-0202 August 2018 Issuance of Amendments to Relocate the Staff Qualification Requirements ML17121A0492017-10-30030 October 2017 Safety Evaluation by the Office of Nuclear Reactor Regulation for the Proposed Alternative for the Use of Encoded Phased Array Ultrasonic Examination Techniques in Lieu of Radiography ML17233A1382017-10-0505 October 2017 Three Mile Island Nuclear Station, Unit 1 - Issuance of Amendment 293 Re: Changes to Technical Specifications 5.4.2, 6.1.2, and 6.2.2 (CAC No. MF9462) ML17137A3932017-06-23023 June 2017 Three Mile Island Nuclear Station, Units 1 And 2 Issuance of Amendment Re: Changes to the Emergency Plan Related to Staffing (CAC No. MF8147) ML17137A3882017-05-0909 May 2017 Safety Evaluation-Ultrasonic Examination Techniques in Lieu of Radiography-Braidwood Station, Units 1 and 2, Byron Station, Units 1 and 2, Calvert Cliffs Nuclear Power Plant, Units 1 and 2, Clinton Power Station, Unit 1, Dresden Nuclear Pow ML17055A6472017-05-0808 May 2017 Brunswick, Catawba, McGuire, Shearon Harris, and H. B. Robinson - Issuance of Amendments to Revise Technical Specifications to Adopt TSTF-522, Revision 0 (CAC Nos. MF8422, MF8423, MF8424, MF8425, MF8426, MF8427, MF8428, and MF8429) ML17025A4092017-02-14014 February 2017 Safety Evaluation Regarding Implementation of Mitigating Strategies and Reliable Spent Fuel Pool Instrumentation Related to Orders EA-12-049 and EA-12-051 (CAC Nos. MF0803 and MF0866) ML16308A0272017-01-10010 January 2017 Relief from the Requirements of the ASME Code ML15225A1582015-10-0101 October 2015 Issuance of Amendment for Temporary Restoration of the Borated Water Storage Tank Cleanup and Recirculation Operation (TAC No. 6504) ML15163A2492015-09-15015 September 2015 Relief Request RR-14-01 Concerning Alternative Root Mean Square Depth Sizing Requirements ML15153A2822015-07-30030 July 2015 Issuance of Amendments Revising the Completion Date for Milestone 8 of the Cyber Security Plan (TAC Nos. MF4728, MF4729, MF4730, MF4731, MF4732, MF4733, MF4734, MF4735, MF4736, MF4737, MF4738, MF4739, MF4740 ML15090A5842015-07-28028 July 2015 Issuance of Amendments Technical Specifications to Modify Reactor Coolant System Pressure Isolation Check Valve Maximum Allowable Leakage Limits ML15141A0582015-07-28028 July 2015 Issuance of Amendments Regarding Emergency Action Level Schemes (TAC Nos. MF4232-MF4251) ML15121A5892015-06-30030 June 2015 Issuance of Amendment Regarding Technical Specifications Task Force (TSTF) Traveler-523, Generic Letter 2008-01, Managing Gas Accumulation, Revision 2, Using the Consolidated Line Item Improvement Process ML14330A3002014-12-30030 December 2014 Issuance of Amendment to Eliminate Certain Technical Specifications Reporting Requirements ML14226A9402014-12-24024 December 2014 Issuance of Amendments Regarding the Emergency Plan Definition of Annual Training (TAC Nos. MF3003, MF3004, MF3005, MF3006, MF3007, MF3008.. ML14175B5932014-07-31031 July 2014 Proposed Alternative to Utilize Code Case N-786, Alternative Requirements for Sleeve Reinforcement of Class 2 and 3 Moderate-Energy Carbon Steel Piping Section XI Division1 ML13325A0232013-12-13013 December 2013 Issuance of Amendment Revision to the Pressure and Temperature Limit Curves and the Low Temperature Overpressure Protection Limits ML13232A0512013-08-28028 August 2013 Relief Request VR-01, Proposed Alternative Testing of the Pressurizer Pilot Operated Relief Valve ML13227A0072013-08-27027 August 2013 End-of-Interval Relief Request RR-12-01, Pressurizer Nozzle-to-Head Weld Examinations ML13227A0242013-08-15015 August 2013 Relief Requests PR-01, PR-02, and VR-02, Associated with the Fifth Ten-Year Inservice Test Interval ML13134A4672013-06-10010 June 2013 Proposed Alternative RR-12-02 Regarding Weld Overlay of the Lower Cold Leg Letdown Nozzle Dissimilar Metal Welds and Alloy 600 Safe-End ML13114A9732013-05-12012 May 2013 Approval of Request to Use a Provision of a Later Addenda of the American Society of Mechanical Engineers Code for Operation and Maintenance of Nuclear Power Plants ML12209A3922012-09-0404 September 2012 Issuance of Amendment Revision to Steam Generator Program Inspection Frequencies and Tube Sample Selection ML12121A6372012-05-10010 May 2012 Request to Use Code Case N-789 ML1210804372012-05-0707 May 2012 Issuance of Amendment Administrative Technical Specification Changes ML1208202662012-03-29029 March 2012 Request to Use Later Edition of Code for Listed Plants ML1134104692011-12-19019 December 2011 (TMI-1) - Third Inservice Inspection Interval Relief Requests RR-11-01 and RR-11-02 ML1123605812011-09-14014 September 2011 Issuance of Amendment Maximum Allowable Power with Inoperable Main Steam Safety Valves ML1121504862011-08-22022 August 2011 Issuance of Amendment Relocation of Equipment Load List from Technical Specifications to Updated Final Safety Analysis Report ML1121403972011-08-15015 August 2011 Proposed Alternative RR-10-02 Regarding Weld Overlay of the Pressurizer Spray Nozzle to Safe-End and Safe-End to Elbow Dissimilar Metal Welds 2023-04-20
[Table view] |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 January 10, 2017 Mr. Bryan C. Hanson President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
THREE MILE ISLAND NUCLEAR STATION, UNIT 1 - RELIEF FROM THE REQUIREMENTS OF THE ASME CODE (CAC NO. MF7753)
Dear Mr. Hanson:
By letter dated May 27, 2016, as supplemented by letter dated September 8, 2016 (Agencywide Documents and Access Management System Accession Nos. ML16148A109 and ML16252A427, respectively), Exelon Generation Company, LLC (the licensee) submitted Relief Request RR-16-01, Revision 1, to the U.S. Nuclear Regulatory Commission (NRC) for the use of alternatives to certain American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),Section XI requirements at the Three Mile Island Nuclear Station (TMI),
Unit 1.
Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(z)(2), the licensee requested to use an alternative on the basis that complying with the specified requirement would result in hardship or unusual difficulty, without a compensating increase in the level of quality and safety. Specifically, the licensee requested to remove 52 nozzle-to-adapter welds from the examination scope of N-722-1, as specified in the TMI inservice inspection (ISi) program.
The NRC staff has determined, as set forth in the enclosed safety evaluation, that complying with the ASME Code requirement would result in hardship or unusual difficulty, without a compensating increase in the level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)(2), and is in compliance with the ASME Code's requirements.
Therefore, the NRC staff authorizes the proposed alternative in Relief Request RR-16-01, Revision 1, in accordance with 10 CFR 50.55a(z)(2) for TMI, Unit 1, for the remaining fourth ISi interval, which ends on April 19, 2022.
This authorization is for the requested relief at TMI, Unit 1, and does not imply or infer the NRC's approval of ASME Code Case N-722-2.
All other ASME Code,Section XI requirements for which relief was not specifically requested and approved remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector.
B. Hanson If you have any questions, please contact the Project Manager, Justin Poole, at 301-415-2048 or by e-mail at Justin.Poole@nrc.gov.
Sincerely,
~~!~
Stephen S. Koenick, Acting Chief Plant Licensing Branch 1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289
Enclosure:
Safety Evaluation cc w/enclosure: Distribution via Listserv
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST RR-16-01. REVISION 1. REGARDING ALTERNATE EXAMINATION OF WELDS AT BOTTOM OF REACTOR VESSEL EXELON GENERATION COMPANY. LLC THREE MILE ISLAND NUCLEAR STATION UNIT 1 DOCKET NO. 50-289
1.0 INTRODUCTION
By letter dated May 27, 2016, (Agencywide Documents Access and Management System (ADAMS) Accession No. ML16148A109), as supplemented by letter dated September 8, 2016, (ADAMS Accession No. ML16252A427), Exelon Generation Company, LLC (the licensee) requested relief from Code Case N-722-1 (N-722-1), "Additional Examinations for PWR Pressure Retaining Welds in Class 1 Components Fabricated with Alloy 600/82/182 Materials,Section XI, Division 1," of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) at the Three Mile Island Nuclear Station (TMI), Unit 1. The licensee submitted Relief Request RR-16-01, Revision 1, to remove 52 nozzle-to-adapter welds from the examination scope of N-722-1, as specified in the TMI inservice inspection (ISi) program.
Specifically, pursuant to Title 1O of the Code of Federal Regulations (10 CFR) 50.55a(z)(2), the licensee requested to use the proposed alternative on the basis that complying with the specified requirement would result in hardship or unusual difficulty, without a compensating increase in the level of quality and safety.
2.0 REGULATORY EVALUATION
The regulation at 10 CFR 50.55a(g)(4) states, in part, that ASME Code Class 1, 2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in ASME Code,Section XI, to the extent practical, within the limitations of design, geometry, and materials of construction of components. TMI, Unit 1, complies with ASME Code,Section XI, 2004 Edition, no addenda.
The regulation at 10 CFR 50.55a(z) states, in part, that alternatives to the requirements of 10 CFR 50.55a(g) may be used when authorized by the U.S. Nuclear Regulatory Commission (NRC) if the licensee demonstrates that (1) the proposed alternatives would provide an acceptable level of quality and safety or (2) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
Enclosure
The regulation at 10 CFR 50.55a(g)(6)(ii)(E), "Augmented ISi requirements: Reactor coolant pressure boundary visual inspections," requires pressurized-water reactor (PWR) plants to augment their ISi program by implementing N-722-1, with conditions, for Class 1 components that are fabricated from Alloy 600/82/182 materials.
Based on the above, and subject to the following technical evaluation, the NRC staff finds that regulatory authority exists for the licensee to request the use of the alternative and the NRC to authorize the proposed alternative.
3.0 TECHNICAL EVALUATION
3.1 Licensee's Proposed Alternative There are 52 nozzle penetrations at the bottom of the reactor vessel allowing incore instrumentation piping (guide tubes) to extend into the reactor vessel. Each nozzle penetration is attached to the reactor vessel bottom shell with a J-groove weld. At the bottom of the reactor vessel shell, the incore instrumentation piping is joined to the downstream piping with a nozzle-to-adapter weld. There are 52 J-groove welds and 52 nozzle-to-adapter welds. The weld identifier, RCT0001 INCORENOZZLES, applies to all J-groove welds and nozzle-to-adapter welds.
The affected components of the relief request are the 52 nozzle-to-adapter welds. The subject welds are (1) classified as Examination Item 815.80 in accordance with N-722-1 in the TMI ISi program, (2) located below the reactor vessel insulation, (3) less than 1-inch in diameter, (4) made of nickel-based Alloy 82/182 filler metal, and (5) not insulated.
In lieu of required examinations of N-722-1 (per 10 CFR 10 CFR 50.55a(g)(6)(ii)(E)), the licensee proposed to remove the nozzle-to-adapter welds from the examination scope of N-722-1 for the fourth ISi interval, which ends on April 19, 2022. Under the proposed alternative, the licensee will no longer perform the bare metal visual examinations of the subject welds, as required by N-722-1.
The licensee stated that inspection of the 52 incore nozzle-to-adapter welds is conducted in a substantive radiation field and that not inspecting the subject welds would eliminate the radiological hardship and overall station personnel exposure, without an adverse reduction in the level of quality and safety.
The licensee believes that no longer performing the bare metal visual examinations of the subject welds does not create an adverse reduction in the level of quality and safety because the subject welds are less susceptible to primary water stress corrosion cracking (PWSCC),
since they experience lower temperatures than those that would cause PWSCC. The licensee noted that N-722-1 was revised to N-722-2 in 2010 with a note that excludes butt welds with an operating temperature less than 525 degrees (°F) from bare metal visual examinations. The licensee further stated that the exclusion of welds that experience 525 °F or less from bare metal visual examinations is consistent with the requirements of ASME Code Case N-770-1, "Additional Examinations for PWR Pressure Retaining Welds in Class 1 Components Fabricated with Alloy 600/82/182 Materials,Section XI, Division 1," that has removed welds at operating temperatures less than 525 °F from the examination scope.
The licensee noted that it will continue to perform visual inspection (VT-2) of the subject welds as part of reactor vessel system leakage (pressure) testing conducted at normal operating temperature and pressure during each refueling outage. The licensee stated that leakage from the subject welds would be visible during the reactor coolant system leakage test, as no insulation is installed over the subject welds.
3.2 NRC Staff Evaluation The NRC staff notes that it has not approved N-722-2. However, the NRC staff recognizes that Note 2 of N-722-2 states, in part, that the butt welds having an operating temperature less than 525 °F are not required to be examined.
The NRC has approved the use of ASME Code Case N-770-1. Paragraph 1100(c) of N-770-1 excludes the examination of Alloy 82/182 welds that experience temperature that is equal to or less than 525 °F. The licensee stated that the operating temperature at the subject welds is less than 525 °F. Therefore, the NRC staff finds it acceptable that the subject welds are excluded from the bare metal visual examinations, as required by N-722-1.
In addition, the NRC staff notes that the ASME Code,Section XI, IWB-2500, does not require inspections of pipes or tubing that are 1-inch or smaller in diameter. Therefore, the NRC staff finds that the licensee is not required to examine the nozzle-to-adapter welds in accordance with the ASME Code,Section XI.
Notwithstanding the above, as part of the system leakage test required by the ASME Code,Section XI, IWA-5000, licensees are required to perform VT-2 visual examinations of components prior to plant startup after each refueling outage. The licensee stated that it will perform the required reactor coolant system leakage test with associated VT-2 visual examination every refueling outage.
With regard to the VT-2 visual examination, the licensee stated that the bottom of the reactor vessel area includes the incore monitoring piping (guide tubes) and the exposed subject nozzle-to-adapter welds. The welds are located several feet overhead, with configuration preventing short distance direct sight inspection. Plant personnel enter the area under the reactor vessel to perform VT-2 visual examination of various components in accordance with the ASME Code,Section XI, IWA-5241 (including IWA-5241 (b)), including insulation on the bottom of the reactor vessel, accessible areas of incore monitoring guide tubes, and the cavity floor and walls below the reactor vessel. The licensee has station procedures that focus on finding water or steam leakage from any pressure retaining boundary or insulation surrounding that boundary, evidence of leakage such as water or moisture collecting/flowing on walls/structures (e.g., puddles on the floor), boric acid residue, areas of general corrosion on pressure retaining components, or evidence of structural distress.
The NRC staff has determined that the licensee's VT-2 visual examinations will detect potential leakage occurring on the subject welds. Therefore, the NRC staff finds that the VT-2 visual examinations of uninsulated subject welds are acceptable to monitor the structural integrity and leak tightness of the subject welds.
The NRC staff finds that the bare metal visual examination of the subject welds in accordance with N-722-1 does lead to substantial radiological dose for the plant personnel because the welds are located at the bottom of the reactor vessel. The NRC staff has determined that performing required examinations per N-722-1 does not provide a compensating increase in the level of quality and safety, considering that the licensee will perform a VT-2 examination of the subject welds every refueling outage.
The NRC staff finds that removal of the 52 nozzle-to-adaptor welds from the examination scope of N-722-1 is acceptable. The NRC staff is basing its finding on the fact that the welds have an operating temperature less than 525 °F and that as part of every refueling outage, the licensee will still perform the VT-2 visual examination of uninsulated subject welds. The NRC staff has determined that the proposed alternative will provide reasonable assurance of the structural integrity and leak tightness of the subject welds.
4.0 CONCLUSION
As set forth above, NRC staff has determined that complying with the ASME Code requirement would result in hardship or unusual difficulty, without a compensating increase in the level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)(2) and is in compliance with the ASME Code's requirements. Therefore, the NRC staff authorizes the proposed alternative in Relief Request RR-16-01, Revision 1, in accordance with 10 CFR 50.55a(z)(2), for TMI, Unit 1, for the remaining fourth ISi interval, which ends on April 19, 2022.
This authorization is for the requested relief at TMI, Unit 1, and does not imply or infer the NRC's approval of ASME Code Case N-722-2.
All other ASME Code,Section XI, requirements for which relief was not specifically requested and approved remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector.
Principal Contributor: J. Tsao Date: January 10, 2017
B. Hanson If you have any questions, please contact the Project Manager, Justin Poole, at 301-415-2048 or by e-mail at Justin.Poole@nrc.gov.
Sincerely, IRA/
Stephen S. Koenick, Acting Chief Plant Licensing Branch 1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289
Enclosure:
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PUBLIC LPL 1 R/F RidsACRS_MailCTR Resource RidsNrrDorlLpl1 Resource RidsNrrDeEpnb Resource RidsNrrLALRonewicz Resource RidsNrrPMThreeMilelsland Resource RidsRgn1 MailCenter Resource JBowen, OEDO ADAMS A ccess1on No.: ML16308A027 *b1y memoran d um daet d OFFICE NRR/DORL/LPL 1/PM NRR/DORL/LPL 1/LA NRR/DE/EPNB/BC* NRR/DORL/LPL 1/(A)BC NAME JPoole LRonewicz DAiiey SKoenick DATE 12/19/2016 12/19/2016 9/19/2016 1/10/2017 OFFICIAL RECORD COPY