Letter Sequence RAI |
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MONTHYEARRA-11-078, Proposed Alternative to Utilize Code Case N-789, Alternative Requirements for Pad Reinforcement of Class 2 and 3 Moderate Energy Carbon Steel Piping for Raw Water Service, Section XI, Division 1.2011-10-0707 October 2011 Proposed Alternative to Utilize Code Case N-789, Alternative Requirements for Pad Reinforcement of Class 2 and 3 Moderate Energy Carbon Steel Piping for Raw Water Service, Section XI, Division 1. Project stage: Request RA-11-087, Response to Request for Additional Information - Proposed Alternative to Utilize Code Case N-789, Alternative Requirements for Pad Reinforcement of Class 2 and 3 Moderate Energy Carbon Steel Piping for Raw Water Service, Section XI, Divisi2011-11-10010 November 2011 Response to Request for Additional Information - Proposed Alternative to Utilize Code Case N-789, Alternative Requirements for Pad Reinforcement of Class 2 and 3 Moderate Energy Carbon Steel Piping for Raw Water Service, Section XI, Divisio Project stage: Response to RAI ML12011A1192012-01-0505 January 2012 NRR E-mail Capture - Preliminary Request for Additional Information Regarding Proposed Alternative to Utilize ASME Code Case N-789 - ME7303 - ME7319 Project stage: RAI ML1200603242012-01-19019 January 2012 Fleet, RAI, Proposed Alternative to Use American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Case N-789 (N-789) Project stage: RAI RA-12-021, Response to Request for Additional Information - Proposed Alternative to Utilize Code Case N-789, Alternative Requirements for Pad Reinforcement of Class 2 and 3 Moderate Energy Carbon Steel Piping for Raw Water Service, Section XI, Divisi2012-02-13013 February 2012 Response to Request for Additional Information - Proposed Alternative to Utilize Code Case N-789, Alternative Requirements for Pad Reinforcement of Class 2 and 3 Moderate Energy Carbon Steel Piping for Raw Water Service, Section XI, Divisio Project stage: Response to RAI ML12121A6372012-05-10010 May 2012 Request to Use Code Case N-789 Project stage: Other 2012-01-19
[Table View] |
NRR E-mail Capture - Preliminary Request for Additional Information Regarding Proposed Alternative to Utilize ASME Code Case N-789 - ME7303 - ME7319ML12011A119 |
Person / Time |
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Site: |
Dresden, Peach Bottom, Oyster Creek, Byron, Three Mile Island, Braidwood, Limerick, Clinton, Quad Cities, LaSalle |
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Issue date: |
01/05/2012 |
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From: |
Joel Wiebe Division of Operating Reactor Licensing |
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To: |
Tom Loomis Exelon Generation Co |
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References |
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TAC ME7303, TAC ME7319 |
Download: ML12011A119 (2) |
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Category:E-Mail
MONTHYEARML24271A0282024-09-26026 September 2024 E-Mail - Dresden Nuclear Power Station, Unit 1 - Site Visit Request for Alternative Schedule to Complete Decommissioning Beyond 60 Years of Permanent Cessation of Operations ML24254A2082024-09-10010 September 2024 NRR E-mail Capture - Quad Cities, Unit Nos. 1 and 2 - Alternative to RV-08, Rev 1, SRV Testing Interval - Acceptance of Requested Licensing Action Re Relief Request Associated with Safety Relief Valve Testing Interval ML24250A1062024-09-0606 September 2024 NRR E-mail Capture - Final RAI - Constellation Energy Generation, LLC - Fleet Request - Proposed Alternative to Utilize Code Case OMN-32 (L-2024-LLR-0030) ML24249A1362024-09-0404 September 2024 EN 57304 - Westinghouse Electric Company, LLC, Final Report - No Embedded Files. Notification of the Potential Existence of Defects Pursuant to 10 CFR Part 21 ML24234A2772024-08-21021 August 2024 NRR E-mail Capture - Final RAI - Constellation Energy, LLC - Fleet Request - Proposed Alternative Concerning Extension of Permanent Relief from Ultrasonic Examination of Reactor Pressure Vessel Circumferential Shell Welds (L-2024-LLR-0031) ML24233A2472024-08-20020 August 2024 Acceptance of Requested Licensing Action Request for Alternative Schedule to Complete Decommissioning Beyond 60 Years of Permanent Cessation of Operations ML24228A1922024-07-29029 July 2024 Request for Additional Information Response Due Date Extension E-Mail String ML24199A1842024-07-15015 July 2024 RAI-LAR for Limerick EPID: L-2024-LLA-0079- Use This Version ML24197A0482024-07-12012 July 2024 Information Request for the Quad Cities Nuclear Station Biennial Problem Identification and Resolution Inspection ML24197A0162024-07-12012 July 2024 NRR E-mail Capture - Final RAI - Constellation Energy Generation, LLC - Fleet Request - License Amendment Request to Adopt TSTF-591 ML24185A1782024-07-0303 July 2024 NRC Email Response to Peach Bottoms Request for Alternative Schedule to Complete Decommissioning Beyond 60 Years of Permanent Cessation of Operations ML24180A0032024-06-28028 June 2024 NRR E-mail Capture - NRC Acceptance Review of Byron/Braidwood Amendment for Transition to Framatome Gaia Fuel (L-2024-LLA-0072) ML24180A0042024-06-28028 June 2024 NRR E-mail Capture - Acceptance Review for Braidwood and Byron - Request for Exemption from 10 CFR 50.46 and Appendix K (L-2024-LLE-0019) ML24192A3642024-06-21021 June 2024 State Rad Health Reply Email Re Draft Environmental Assessment for the Three Mile Island Unit 2 ML24176A0232024-06-21021 June 2024 NRR E-mail Capture - Dresden Nuclear Power Station, Units 2 and 3 - Acceptance Review of the Amendment Request to Adopt 10 CFR 50.69 ML24176A0182024-06-20020 June 2024 NRR E-mail Capture - NRC Acceptance Review of Byron/Braidwood Amendment to Remove Extraneous Detail Related to Beacon ML24176A1292024-06-20020 June 2024 Estimated Completion Schedule Change Email ML24170A3912024-06-18018 June 2024 NRR E-mail Capture - Revision of Estimated Hours to Complete Review of Byron/Braidwood Amendment to Revise TS 3.7.15, 3.7.16, and 4.3.1 (L-2023-LLA-0136) ML24159A0122024-06-0606 June 2024 NRR E-mail Capture - Dresden Nuclear Power Station, Units 2 and 3 - Acceptance of Licensing Amendment to Adopt TSTF-505 and TSTF-591 ML24156A0082024-05-31031 May 2024 NRR E-mail Capture - Constellation Energy, LLC - Fleet Request - Acceptance of Proposed Alternative Concerning Extension of Permanent Relief from Ultrasonic Examination of Reactor Pressure Vessel Circumferential Shell Welds (L-2024-LLR-0031 ML24141A2452024-05-20020 May 2024 NRR E-mail Capture - NRC Acceptance Review of Byron/Braidwood Amendment to Delete Technical Specification 5.6.5.b.5 (L-2024-LLA-0055) ML24163A3522024-05-15015 May 2024 Meeting Feedback from May 14, 2024, Meeting with Constellation on Peach Bottom Atomic Power Station Units Nos. 2 and 3 ML24135A0182024-05-13013 May 2024 NRR E-mail Capture - Draft Request for Additional Information Quad Cities TSTF-505 Amendment ML24131A0612024-05-10010 May 2024 NRR E-mail Capture - Constellation Energy Generation, LLC - Fleet Request - Acceptance of Proposed Alternative to Utilize Code Case OMN-32 (L-2024-LLR-0030) ML24107A9192024-05-0808 May 2024 Email to Christian Williams Re Decision on the Limerick Exemption ML24222A4092024-05-0303 May 2024 NRR E-mail Capture - Request for Additional Information Regarding Reactor Water Cleanup (RWCU) Pump Rooms - L-2023-LLA-0118 ML24107A9202024-05-0303 May 2024 Email to Christian Williams Re Availability of Environmental Assessment for the Limerick Exemption ML24122C6742024-05-0101 May 2024 Response to a Request from NRC Review of a Draft EA for an Exemption for the Limerick Generating Station ML24122B5072024-05-0101 May 2024 NRR E-mail Capture - Constellation Energy Generation, LLC - Fleet Request - Acceptance of License Amendment Request to Adopt TSTF-591, Revision 0 ML24086A5182024-04-30030 April 2024 E-mail to Christian Williams Decision on the Exemption Request for Quad Cities ML24122C6702024-04-29029 April 2024 Request from NRC Review of a Draft EA for an Exemption for the Limerick Generating Station ML24086A4782024-04-24024 April 2024 Email to Christian Williams Availability of Environmental Assessment for the Quad Cities Exemption ML24114A1702024-04-15015 April 2024 Request for State Review of the Quad Cities HI-STORM Exemption Request Environmental Assessment ML24102A2422024-04-10010 April 2024 NRR E-mail Capture - Draft Request for Additional Information Quad Cities TSTF-505 and 50.69 Amendments ML24066A0802024-04-0101 April 2024 Email to Christian Williams Decision on the Exemption Request for Dresden Nuclear Power Station Unit 2 and Unit 3 Independent Spent Fuel Storage Installation in Morris, Illinois ML24089A0102024-03-29029 March 2024 NRR E-mail Capture - Quad Cities Unit Nos. 1 and 2 - Alternative to Core Spray Pump Testing - Acceptance of Requested Licensing Action Relief Request Associated with the Sixth Inservice Testing Interval ML24088A3192024-03-28028 March 2024 Audit Plan Associated with Peach Bottom, Unit 1 - 10 CFR 50.82(a)(3) Alternate Decommissioning Schedule ML24065A4892024-03-28028 March 2024 Email to Christian Williams Availability of Environmental Assessment for the Exemption Request for Dresden Nuclear Power Station Unit 2 and Unit 3 Independent Spent Fuel Storage Installation in Morris, Illinois ML24078A3772024-03-15015 March 2024 Email to the State of Illinois Requesting Review of the Dresden Exemption Request Environmental Assessment ML24066A1532024-03-0606 March 2024 NRR E-mail Capture - Request for Additional Information TSTF-505, R2, Provide Risk-Informed Extended Completion Times, RITSTF (Risk-Informed Technical Specification Task Force) Initiative 4b and 10 CFR 50.69 License Amendments ML24066A0872024-03-0404 March 2024 NRR E-mail Capture - Dresden 2 and 3 - Request for Additional Information for Alternative Request I5R-22 ML24067A1242024-03-0101 March 2024 Email to Christian Williams: Request for Additional Information Regarding Dresden Relief Request Dated February 23, 2024 ML24065A2922024-02-28028 February 2024 2/28/24 Email from Constellation: Clarifying Information Regarding Dresden Relief Request Dated February 23, 2024 ML24053A3382024-02-22022 February 2024 NRR E-mail Capture - Final RAI - Constellation Energy Generation, LLC - Fleet Request - Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds (L-2023-LLR-0062) ML24051A0652024-02-16016 February 2024 Digital I&C LAR RAIs Re HFE (Email) ML24064A1222024-02-0606 February 2024 Biennial Problem and Identification Inspection Request for Information ML24030A0022024-01-30030 January 2024 NRR E-mail Capture - NRC Acceptance Review for Braidwood Station, Units 1 and 2, Proposed Alternative to the Distribution Requirements of ASME Code Table IWC-2411-1 for the Steam Generators ML24039A0412024-01-30030 January 2024 NRR E-mail Capture - Request for Additional Information Regarding Braidwood Request for Alternative (I4R-18) ML24026A2922024-01-26026 January 2024 – Request for Additional Information Regarding Limerick Digital Instrumentation and Controls License Amendment Request ML24011A2332024-01-11011 January 2024 Request for Additional Information - License Amendment Request (ML23058A064) (EPID L-2023-LLA-0026 - Three Mile Island, U2: Amendment Historic and Cultural Resources) 2024-09-06
[Table view] |
Text
From: Wiebe, Joel To: Tom Loomis
Subject:
Preliminary Request for Additional Information Regarding Proposed Alternative to Utilize ASME Code Case N-789
- ME7303 - ME7319 Date: Thursday, January 05, 2012 9:12:00 AM The purpose of providing a preliminary request for information is to ensure the request is clear and, when applicable, to identify any information that may be considered proprietary.
If you need a conference call to clarify the questions, contact me by e-mail or phone (301-415-6606).
By letter dated October 7, 2011 (Agencywide Document Access Management System (ADAMS) Accession No. ML112800669), with a supplement dated November 10, 2011 (ADAMS Accession No. ML113180232), Exelon Generating Company submitted for the Nuclear Regulatory Commission review and approval a proposed alternative to use American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Case N-789 (N-789), "Alternative Requirements for Pad Reinforcement of Class 2 and 3 Moderate-Energy Carbon Steel Piping for Raw Water Service,Section XI, Division 1," at Braidwood Units 1 and 2, Byron Units 1 and 2, Clinton Unit 1, Dresden Units 2 and 3, LaSalle Units 1 and 2, Limerick Units 1 and 2, Oyster Creek, Peach Bottom Units 2 and 3, Quad Cities Units 1 and 2, and Three Mile Island Unit 1. To complete its review, the staff requests for additional information as follows. The following questions are related to the submittal dated November 10, 2011 which contains the latest version of the proposed alternative.
- 1. Paragraphs 1(e) and 8(d) of N-789 state that reinforcing pads, including those installed during a refueling outage, shall not remain in service beyond the end of the next refueling outage.
- a. Confirm that both the pressure pad and structural pad as discussed in Section 3 of N-789 are part of the reinforcing pads.
- b. Confirm that both the pressure and structural pads will not remain in service beyond the end of the next refueling outage.
- c. If the repair is performed in mid-cycle (e.g., one month before the scheduled refueling outage), discuss when is the 'next refueling outage'.
- d. There are piping systems that are required to be functional and thus cannot be repaired during refueling outages. The repair for these pipes can only be performed when the plant (the unit) is operating. The maximum service life to the next refueling outage would not be applicable or appropriate for these piping systems. Provide the service life of the reinforcing pads for these piping systems.
- e. Section 2 of the proposed alternative lists the end date of the 10-year inservice inspection (ISI) interval for each unit. Confirm that the end date of the 10-year ISI interval coincides with the scheduled refueling outages for each unit. If it is not, discuss how the repair would be dispositioned when the end date of the 10-year ISI interval is reached during the mid-cycle because the duration of the proposed alternative is requested to be limited to the end of 10-year ISI interval.
- 2. Section 3.1(1) of N-789 states that "...[t]he pressure pads are designed to retain...full structural integrity... assuming a corrosion rate of either 2 times the actual measurement corrosion rate in that location or 4 times the estimated
maximum corrosion rate for the system..."
- a. Discuss how the actual measurement corrosion rate will be derived (e.g.,
what is the period of time between two measurements taken? Would the measured corrosion rate be based on the average of several measurements or only one measurement).
- b. Discuss whether the maximum (worst) corrosion rate determined from both approaches in N-789 (i.e., the greater of the 2 times the actual measurement corrosion rate or 4 times the estimated maximum corrosion rate) will be used in the pressure pads design. If not, provide justification why the worst corrosion rate is not used in the reinforcing pad design.
- c. Discuss how the corrosion rate is used to design the reinforcing pad (e.g.,
how the thickness and size of the pad and weld size are designed based on the corrosion rate?).
- d. Discuss what the acceptance criteria are for the 'full structural integrity' of piping (provide reference specific ASME Code paragraphs that define the full structural integrity).
- 3. The design requirements in Section 3.2 and examination requirements in Section 6 of N-789 stipulate the use of the Construction Code or ASME Code Section III.
- a. Clarify the edition and addenda of the ASME Code,Section III that will be used if it is used in lieu of the Construction Code.
- b. N-789 also stipulates the use of various IWA paragraphs of the ASME Code,Section XI. Confirm that the edition and addenda of the ASME Code,Section XI, will be based on the Code of Record for the specific 10-year inservice inspection interval at each nuclear unit covered under the proposed alternative.
- 4. Section 4 of N-789 discusses requirements for installing the reinforcing pad on water-backed piping. Discuss whether N-789 permits a reinforcing pad be installed on a leaking area of the pipe. If yes, discuss how welding will be conducted on a leaking pipe to minimize fabrication defects (e.g., porosity and hydrogen cracking) in the weld.
- 5. Section 8 of N-789 stipulates inservice monitoring requirements for the structural pad, but not the pressure pad. In section 5 of the Proposed Alternative, the licensee stated that for the pressure pads, inservice monitoring will not be required because the design of pressure pads conservatively assumes 2 times the actual measured corrosion rate or 4 times if using an estimated rate.
- a. Justify that either 2 times the actual measured corrosion rate or 4 times the estimated maximum corrosion rate for the system is adequate to ensure conservatism that the pressure pad will not leak or lose structural integrity prior to its removal.
- b. Even if a conservative corrosion rate is used in the pad design, justify why the pressure pad does not need inservice inspections.
- 6. Discuss whether the proposed alternative will be applied to buried piping. If yes, discuss how the required examinations will be performed if the pipe is buried after the reinforcing pad is installed.