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MONTHYEARML1105500792011-02-24024 February 2011 Acceptance Review for Calvert Cliffs TAC No. ME5423 Project stage: Acceptance Review ML1108806722011-04-12012 April 2011 ME5423, RAI Letter to Licensee RR-PZR-01 Project stage: RAI ML11126A1862011-05-0404 May 2011 Response to Request for Additional Information: Relief Request for Modifications to Pressurizer Heater Sleeve and Lower Level Nozzle Penetrations (RR-PZR-01) Project stage: Response to RAI ML11132A0572011-05-23023 May 2011 Proprietary Information Determination Letter to Licensee Relief Request RR-PZR-01 Project stage: Other ML11264A0212011-09-19019 September 2011 Pressurizer Heater Sleeve Replacement Telephone Call Project stage: Request ML1133605262011-12-0909 December 2011 Relief Request for Modifications to Pressurizer Heater Sleeve and Lower Level Nozzle Penetrations (RR-PZR-01) - Calvert Cliffs Nuclear Power Plant, Unit No. 1 Project stage: Other 2011-04-12
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Category:Letter
MONTHYEARIR 05000317/20230042024-02-0101 February 2024 Integrated Inspection Report 05000317/2023004 and 05000318/2023004 ML24029A0102024-01-29029 January 2024 Request for Information and Notification of Conduct of IP 71111.21.N.04, Age-Related Degradation, Reference Inspection Report 05000317/2024010 and 05000318/2024010 ML24003A8872024-01-19019 January 2024 Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0033 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting)) 05000318/LER-2023-004, Submittal of LER 2023-004-00 for Calvert Cliffs Nuclear Power Plant, Unit 2, Submittal of Automatic Reactor Trip from Reactor Protection System Actuation Due to Loss of Unit Service Transformer2024-01-16016 January 2024 Submittal of LER 2023-004-00 for Calvert Cliffs Nuclear Power Plant, Unit 2, Submittal of Automatic Reactor Trip from Reactor Protection System Actuation Due to Loss of Unit Service Transformer ML24011A0732024-01-11011 January 2024 Proposed Alternative to the Requirements for Repair/Replacement of Saltwater (SW) System Buried Piping 05000318/LER-2023-002, Forward LER 2023-002-00 for Calvert Cliffs Nuclear Power Plant, Unit 2, Automatic Reactor Trip from Reactor Protection System Actuation Due to Loss of Unit Service Transformer2024-01-0808 January 2024 Forward LER 2023-002-00 for Calvert Cliffs Nuclear Power Plant, Unit 2, Automatic Reactor Trip from Reactor Protection System Actuation Due to Loss of Unit Service Transformer 05000318/LER-2023-003, Forward LER 2023-003-00 for Calvert Cliffs Nuclear Power Plant, Unit 2, Manual Actuation of Auxiliary Feedwater System Due to 22 Steam Generator Feedwater Pump Trip2024-01-0808 January 2024 Forward LER 2023-003-00 for Calvert Cliffs Nuclear Power Plant, Unit 2, Manual Actuation of Auxiliary Feedwater System Due to 22 Steam Generator Feedwater Pump Trip ML24005A0222024-01-0505 January 2024 Revised Steam Generator Tube Inspection Reports ML23304A0642024-01-0202 January 2024 Issuance of Amendment No. 349 to Modify the Long-Term Coupon Surveillance Program RS-23-125, Request for Exemption from 10 CFR 2.109(b)2023-12-0707 December 2023 Request for Exemption from 10 CFR 2.109(b) ML23331A2992023-11-27027 November 2023 Submittal of Condition Prohibited by Technical Specifications Due to Failure to Sample Diesel Generator Fuel Oil Storage Tank IR 05000317/20230102023-11-20020 November 2023 Biennial Problem Identification and Resolution Inspection Report 05000317/2023010 and 05000318/2023010 ML23318A4722023-11-14014 November 2023 Supplement to License Amendment Request to Adopt TSTF-59-A ML23317A1032023-11-10010 November 2023 Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information ML23317A1192023-11-10010 November 2023 Constellation Energy Generation, LLC - 2023 Annual Report - Guarantees of Payment of Deferred Premiums ML23310A0442023-11-0707 November 2023 Project Manager Assignment IR 05000317/20230402023-11-0202 November 2023 95001 Supplemental Inspection Report 05000317/2023040 and Follow-Up Assessment Letter IR 05000317/20230032023-11-0101 November 2023 Integrated Inspection Report 05000317/2023003 and 05000318/2023003 IR 05000317/20230902023-10-26026 October 2023 Final Significance Determination of a White Finding with Assessment Follow-Up and Notice of Violation; Inspection Report 05000317/2023090 ML23289A1202023-10-16016 October 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation RS-23-097, Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans2023-10-12012 October 2023 Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans RS-23-108, Proposed Alternative for Examinations of Examination Categories B-B, B-D, and C-A Steam Generator Pressure Retaining Welds and Full Penetration Welded Nozzles2023-10-11011 October 2023 Proposed Alternative for Examinations of Examination Categories B-B, B-D, and C-A Steam Generator Pressure Retaining Welds and Full Penetration Welded Nozzles RS-23-105, Proposed Alternative for Examinations of Examination Category C-B Steam Generator Nozzle-to-Shell Welds and Nozzle Inside Radius Sections2023-10-10010 October 2023 Proposed Alternative for Examinations of Examination Category C-B Steam Generator Nozzle-to-Shell Welds and Nozzle Inside Radius Sections ML23279A1202023-10-0606 October 2023 Response to NRC Inspection Report and Preliminary White Finding IR 05000317/20230502023-09-29029 September 2023 Special Inspection Report 05000317/2023050 and Preliminary White Finding and Apparent Violation ML23272A1032023-09-29029 September 2023 Condition Prohibited by Technical Specifications Due to Inoperable Nuclear Instrumentation at Very Low Power IR 05000317/20234012023-09-18018 September 2023 Cyber Security Inspection Report 05000317/2023401 and 05000318/2023401 ML23254A0012023-09-0505 September 2023 Registration of Use of Casks to Store Spent Fuel IR 05000317/20230052023-08-31031 August 2023 Updated Inspection Plan for Calvert Cliffs Nuclear Power Plant, Units 1 and 2 (Report 05000317/2023005 and 05000318/2023005) ML23158A1952023-08-30030 August 2023 R. E. Ginna - Issuance of Amendments to Adopt TSTF-273-A, Revision 2, Safety Function Determination Program Clarifications ML23241A8412023-08-29029 August 2023 Response to Request for Additional Information - Proposed Alternative to the Requirements for Repair/Replacement of Saltwater (SW) System Buried Piping ML23240A3872023-08-28028 August 2023 Senior Reactor and Reactor Operator Initial License Examinations ML23151A3472023-08-21021 August 2023 Issuance of Amendments to Adopt TSTF-295-A, Modify Note 2 to Actions of PAM Table to Allow Separate Condition Entry for Each Penetration ML23219A1662023-08-16016 August 2023 Request for Additional Information Regarding Proposed Alternative to the Requirements for Repair/Replacement of Saltwater (SW) System Buried Piping (EPID: L-2023-LLR-0006) - Non-proprietary ML23228A1002023-08-15015 August 2023 Notification of Readiness for NRC 95001 Inspection ML23188A0402023-08-0808 August 2023 Issuance of Amendment Nos. 346 and 324 Adoption of TSTF-577, Revised Frequencies for Steam Generator Tube Inspections, Revision 1 ML23214A1572023-08-0707 August 2023 Correction to the Renewed Facility Operating License Page 3 in Amendment No 345 IR 05000317/20230022023-08-0303 August 2023 Integrated Inspection Report 05000317/2023002 ML23188A0512023-07-13013 July 2023 Correction to the Renewed Facility Operating License Pages in Amendment Nos. 336 and 314 ML23186A0372023-07-13013 July 2023 Correction to the Renewed Facility Operating License Pages in Amendment Nos. 340 and 318 IR 05000317/20233012023-07-12012 July 2023 Initial Operator Licensing Examination Report 05000317/2023301 and 05000318/2023301 IR 05000317/20230122023-07-10010 July 2023 Commercial Grade Dedication Report 05000317/2023012 and 05000318/2023012 ML23180A2362023-06-29029 June 2023 Correction of Errors on Technical Specification Pages RS-23-083, Withdrawal - Proposed Alternatives Related to the Steam Generators2023-06-27027 June 2023 Withdrawal - Proposed Alternatives Related to the Steam Generators ML23156A6752023-06-20020 June 2023 Request for Withholding Information from Public Disclosure for Proposed Alternative to the Requirements for Repair/Replacement of Saltwater System Buried Piping 2024-02-01
[Table view] Category:Request for Additional Information (RAI)
MONTHYEARML24012A0492024-01-11011 January 2024 Request for Additional Information Regarding Final Response to Generic Letter 2004-02 ML23219A1662023-08-16016 August 2023 Request for Additional Information Regarding Proposed Alternative to the Requirements for Repair/Replacement of Saltwater (SW) System Buried Piping (EPID: L-2023-LLR-0006) - Non-proprietary ML23160A0222023-06-0606 June 2023 NRR E-mail Capture - Calvert Cliffs - Long Term Coupon Surveillance Program RAI ML23156A0102023-06-0404 June 2023 NRR E-mail Capture - Calvert Cliffs - RAI License Amendment Request for Emergency Desiel Generator ML22179A2112022-06-28028 June 2022 Notification of Conduct of a Fire Protection Team Inspection ML22129A0132022-05-0606 May 2022 NRR E-mail Capture - Draft RAIs for Requests for Alternatives I4R-17, I4R-23, ISI-05-018, I6R-10 ML22271A0772022-05-0606 May 2022 NRR E-mail Capture - Final RAIs 9.1.2021 Constellation Relief Request ML22091A0852022-04-0101 April 2022 NRR E-mail Capture - Braidwood and Byron - Final RAI Regarding Proposed Alternative for Various Pressurizer Welds (EPID L-2021-LLR-0035 and 0036) ML22091A2392022-04-0101 April 2022 NRR E-mail Capture - Calvert Cliffs - Formal RAI for Proposed Alternative for Examinations of Certain Pressurizer Welds ML22041B5362022-02-10010 February 2022 NRR E-mail Capture - Constellation Energy Generation, LLC - Request for Additional Information Regarding Fleet License Amendment Request to Adopt TSTF-541 ML21287A0322021-10-13013 October 2021 Request for Additional Information Re Proposed Alternative for Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds ML21287A0932021-10-0505 October 2021 Request for Additional Information: Calvert Cliffs 1 & 2 LAR to Revise Spent Fuel Pool Cooling - Shutdown Cooling Systems Licensing Basis (EPID L-2021-LLA-0112) (Email) ML21256A1902021-09-10010 September 2021 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding License Transfer Application ML21187A2232021-07-29029 July 2021 Temporary Instruction 2515/194 Inspection Documentation Request ML21180A1562021-06-28028 June 2021 Request for Additional Information Regarding License Amendment Request Concerning Containment Sump ML21144A2132021-05-24024 May 2021 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding License Transfer Application ML21130A0382021-05-21021 May 2021 Memo to File - Draft Request for Additional Information Relief Request CISI-03-01 Concerning Containment Unbonded Post-Tensioning System Inservice Inspection Requirements ML21117A0342021-05-0505 May 2021 Request for Additional Information Regarding Proposed Alternative to Use ASME Code Case N-893 ML21062A0652021-03-0101 March 2021 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding Proposed Fleet Alternative to Documentation Requirements for Pressure Retaining Bolting ML21053A3142021-02-22022 February 2021 Information Request for a Triennial Baseline Design Bases Assurance Inspection (Team); Inspection Report 05000317/2021010 and 05000318/2021010 ML21049A2572021-02-18018 February 2021 Request for Additional Information Byron/Dresden Proposed Changes to Site Emergency Plans to Support Post-Shutdown and Permanently Defueled Conditions (EPID-2020-LLA-0240 & EPID-2020-LLA-0237) ML21029A3302021-01-29029 January 2021 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding Fleet Alternative Request to Use ASME Code Case N-885 ML20275A0032020-09-30030 September 2020 Request for Additional Information Regarding Alternative Request Re Inservice Inspection Impracticality (L-2020-LLR-0089) ML20167A2532020-06-15015 June 2020 Second Request for Additional Information Regarding License Amendment Request Concerning Emergency Diesel Generator Surveillance Requirements for Frequency and Voltage Tolerances ML20157A0782020-06-0505 June 2020 Request for Additional Information Regarding License Amendment Request Concerning Emergency Diesel Generator Surveillance Requirements for Frequency and Voltage Tolerances ML20153A7042020-06-0101 June 2020 NRR E-mail Capture - Preliminary RAI for Fleet Request to Use Alternative OMN-26 ML20135H0132020-05-14014 May 2020 IP 71111.17T (50.59) List of Documents Request ML20083F5892020-03-21021 March 2020 Request for Additional Information Regarding License Amendment Request Concerning Reactor Coolant Pump Flywheel Inspection Program ML19275H1362019-10-0202 October 2019 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding Request to Use ASME Code Case N-879 ML19261B2202019-09-18018 September 2019 Request for Additional Information Regarding Final Response to Generic Letter 2004-02 ML19179A0612019-07-19019 July 2019 Three Mile Point 1 - Supplemental Information Needed to Proposed Alternative to Use ASME Code Case N-879 ML19155A1612019-06-11011 June 2019 Changes to Draft Request for Additional Information Request to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Systems, Structures and Components ML19155A1272019-06-0404 June 2019 Request for Additional Information Regarding Request to Adopt 10 CFR 50.69 Risk Informed Categorization and Treatment of Systems, Structures, and Components ML19070A0192019-03-11011 March 2019 Request for Additional Information Regarding Exemption Request from 10CFR50.46(A)(1) to Support Resolution of GSI-191 ML19025A1202019-01-24024 January 2019 NRR E-mail Capture - Calvert Cliffs, Fitzpatrick, and Nine Mile Point - Request for Additional Information Regarding License Amendment Request to Revise Emergency Response Organization Staffing ML18347A3972018-12-13013 December 2018 Request for Additional Information Regarding Relocation of Emergency Operation Facility ML18138A1372018-05-22022 May 2018 Plants, Units 1 and 2 - Request for Additional Information Regarding Risk Informed Technical Specification Completion Times (CAC Nos. MF7415 and MF7416; EPID L-2016-LLA-0001) ML18128A3842018-05-0808 May 2018 Plants, Units 1 and 2 - Draft Request for Additional Information Regarding Risk-Informed Technical Specification Completion Times (CAC Nos. MF7415 and MF7416; EPID L-2016-LLA-0001) ML18102A2372018-04-12012 April 2018 NRR E-mail Capture - Calvert Cliffs, Ginna, and Nine Mile Point - Request for Additional Information Regarding License Amendment Request to Revise Emergency Action Level Schemes (EPID-L-2017-LLA-0237) ML18067A1482018-03-0808 March 2018 Enclosurequest for Additional Information (Letter to P. R. Simpson Request for Additional Information Regarding Exelon Generating Company, Llc'S Decommissioning Funding Plan Update for Independent Spent Fuel Storage Installation) ML17345A0912018-01-19019 January 2018 Plants, Units 1 and 2 - Request for Additional Information Regarding Alternative Request SI-RR-01, Rev. 0 (CAC Nos. MG0068 and MG0069; EPID L-2017-LLR-0078) ML17346A9092017-12-21021 December 2017 Request for Additional Information Regarding Risk-Informed Technical Specification Completion Times (CAC Nos. MF7415 and MF7416; EPID L-2016-LLA-0001) ML17331B1342017-12-12012 December 2017 2, and R.E. Ginna Nuclear Power Plant - Request for Additional Information - Regarding ML17304A9412017-11-13013 November 2017 Request for Additional Information Regarding Risk-Informed Technical Specification Completion Times (CAC Nos. MF7415 and MF7416; EPID L-2016-LLA-0001) ML17285B1962017-10-27027 October 2017 Request for Additional Information Regarding Generic Letter 2016-01, Monitoring of Neutron-Absorbing Materials in Spent Fuel Pools. ML17075A0152017-03-16016 March 2017 E-mail from R. Guzman to E. Villar - Calvert Cliffs Unit Nos. 1 and 2 - Request for Additional Information License Amendment Request - Control Room Emergency Ventilation System ML17062A4912017-03-0303 March 2017 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding Fleet Alternative to RPV Threads in Flange Examination (CAC Nos. MF8712-MF8729) ML16222A1252016-08-0909 August 2016 Request for Additional Information - Relief Request No. RR-ISI-04-11, 2016/08/08 E-mail from R.Guzman to T.Loomis ML15299A2792015-11-0303 November 2015 Request for Additional Information Regarding Relief Request for Dissimilar Metal Butt Welds ML15230A0322015-08-13013 August 2015 Request for Additional Information Regarding the National Association Standard 805 License Amendment Request Fire Protection 2024-01-11
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UNITED NUCLEAR REGULATORY WASHINGTON, D.C. 20555-0001 April 12.2011 Mr. George H. Gellrich, Vice President Calvert Cliffs Nuclear Power Plant, LLC Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702 CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1, REQUEST FOR ADDITIONAL INFORMATION RE: RELIEF REQUEST NO. RR-PZR-01 FOR MODIFICATIONS TO THE PRESSURIZER HEATER SLEEVE AND LOWER LEVEL NOZZLE PENETRATIONS (TAC NO. ME5423)
Dear Mr. Gellrich:
By letter dated January 31,2011, and pursuant to Title 10 of the Code of Federal Regulations 50.55a(a)(3)(i), Calvert Cliffs Nuclear Power Plant, LLC submitted relief request number PZR-01 for Nuclear Regulatory Commission (NRC) approval.
RR-PZR-01, which is an alternative to the American Society of Mechanical Engineers Boiler and Pressure Code requirements, would permit modifications to the Calvert Cliffs Unit No. 1 pressurizer heater sleeve and lower level nozzle penetrations in order to mitigate the propensity for primary water stress-corrosion cracking from occurring.
The NRC staff has determined that additional information is needed to complete its review. The staff's request for additional information (RAI) is enclosed.
Based upon discussions with your staff, we understand that you will respond to the enclosed RAI by May 6, 2011. Please contact me at 301-415-1364 if you have any questions.
Sincerely, .
Douglas V. Pickett, Senior Project Manager Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-317
Enclosure:
As stated cc w/encl: Distribution via Listserv REQUEST FOR ADDITIONAL INFORMATION CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1 RELIEF REQUEST RR-PZR-01 FOR MODIFICATION TO PRESSURIZER HEATER SLEEVE NOZZLE PENETRATION DOCKET NO. 50-317 By letter dated January 31, 2011, Calvert Cliffs Nuclear Power Plant, LLC submitted for NRC review and approval Relief Request RR-PZR-01 to perform modifications to Calvert Cliffs Unit 1 pressurizer heater sleeve and lower level nozzle penetrations to mitigate the potential for primary water stress-corrosion cracking.
The section and page numbers below refer to PZR-01. Section 1, Page 1, states that the new heater sleeve and instrument nozzle will be made of stainless steel type 316/316L.
(1) Provide the inside and outside diameters (or the nominal diameter and wall thickness) of the new sleeve; (2) Section 4, page 4, second paragraph, states that " ... Stainless steel 316 base material with less than 0.03% maximum carbon content, and ER309 weld material with 0.03% maximum carbon content, both of which are resistant to PWSCC, will be used for the modifications.
The stainless steel material to be used is dual certified as it meets both the low carbon content requirement of the 'T' grade and the mechanical properties of the "non-L" grade materiaL .. " Describe how stainless steel 316 is combined with stainless steel 316L to achieve a dual certified material and (3) Clarify the "T" grade. Cracking has occurred in stainless steel components resulting from contact with halogens (such as chlorides and fluorides) or being sensitized.
(1) Discuss whether Regulatory Guide (RG) 1.44, "Control of the Use of Sensitized Stainless Steel," will be followed in welding of the new sleeve. If yes, discuss the measures to minimize sensitization in the new sleeve per RG 1.44. Provide justification for any deviations from RG 1.44; (2) Discuss measures to limit the contact with halogens; and (3) Discuss pressurized-water reactor operating experience using the stainless steel heater sleeves in pressurizers. Section 2, page 1, cited Code Case N-638-1 as the applicable code case. The NRC has approved Code Case N-638-4 as documented in NRC RG 1.147, Revision 16. Discuss why Code Case N-638-4 was not used as the applicable code case in Request RR-PZR-01. Section 4, page 4, discusses the five steps of sleeve modification.
Step 2 states that " ... Liquid penetrant (PT) examination of the machined area that is to be welded ... " This inspection is needed to ensure that prior to modification, no flaws exist in the lower head penetration bore as a result of machining or existing degradation.
Any flaws occurring on the bore surface of the lower head need to be repaired before installing the new sleeve. Discuss whether the entire machined area in the bore will be inspected with PT. If not, justify how the bore is demonstrated to be free of defects prior to sleeve installation.
Enclosure
-2 Section 4, page 4, Step 3 states that"... Welding the replacement stainless steel lower sleeve/nozzle to the pressurizer bottom head using stainless steel weld material. (Refer to Figure 2) .. ." Confirm that the welding in Step 3 refers to the weld joining the new sleeve to the bore and is located inside the bore, not the outside surface of the pressurizer bottom head. Specify the axial length of the inside weld per the design specification and identify the length in Figure 2. Discuss the verification procedure to ensure that the actual weld axial length satisfies the designed length. Section 4, page 4, Step 4 states that" ... Machining the weld inner surface and adjacent area to provide a surface suitable for nondestructive examination (NDE) ... " (1) Specify the exact axial length of the adjacent area that will be machined in Figure 2, and (2) Describe in detail the machining procedure, e.g., what is the thickness that will be removed, what is the quality control procedure, what is the surface finish requirement, and will there be any cold work imposed on the weld? Section 4, page 4, Step 5 states that " ... PT and ultrasonic (UT) examination of the weld and adjacent area (Refer to Figure 2) ... " Section 5.2, page 6, third paragraph, states that " ... The PT area includes the new weld surface and the 1/2 inch minimum distance above and below the weld ... " Provide the axial length of the heat affected zone and significant residual stress region in the new sleeve and the ferritic steel of the lower head to demonstrate that 0.5 inch is sufficient. Section 4. The final sleeve configuration after modification is not clearly depicted in Figure 2. It is not clear in Figure 2 whether there is a gap between the bottom of the old sleeve and the top of the new sleeve inside the bore even though Figure 3 seems to suggest that there is a gap. Also, it appears that there is no weldment at the junction of the bottom of the new sleeve and the outside surface of the pressurizer head shell. Submit a new figure or modify Figure 2 to document the final configuration after modification.
The figure for the final sleeve configuration should include the following information:
(1) the heating element joining the new sleeve, (2) the axial length of the gap between the old and new sleeve, (3) whether a weld exists at the junction of the outside surface of the pressurizer and the new sleeve, (4) the original J-groove weld with respect to the original sleeve, (5) the system pressure boundary weld, and (6) relevant dimensions (e.g., weld length). Section 4. Figure 1 shows various bore diameters after machining without explanation:
(1) Explain why there are two different machined diameters in the bore and show their diametrical and axial dimensions; and (2) Include the location of the original J-groove weld in Figure 1. 10. Provide a diagram/figure that shows the existing configuration of the sleeve, heating element, and weld(s) with respect to the pressurizer lower head before modification.
-3 11. Section 4. (1) Discuss whether the new sleeve will be roll-expanded when it is inserted into the bore before welding. If not, discuss how the sleeve can be held in place before welding and how the crevice between the new sleeve and the bore can be minimized to prevent the potential crevice corrosion; and (2) In the lower part of Figure 2, explain why an empty space/annulus region exists between the new sleeve outer wall and the bore. 12. Section 5.2, page 6, mid-page, states that " ... The UT is qualified to detect flaws in the new weld and base metal interface beneath the new weld ... The volume of interest for UT includes the new weld, the bottom head low alloy steel base material heat affected zone, and the sleeve/nozzle to weld interface and will be covered to the maximum extent practicaL" (1) Discuss to which ASME Code Section and subarticles is the UT qualified, and (2) Section 5.3, page 7, 6 th paragraph states that the weld configuration precludes examination of a small portion of the ferritic steel heat affected zone that is shadowed by the interface of the OD of the nozzle. Provide the specific examination coverage (percentage of the required examination volume) of the small portion of the ferritic steel heat affected zone that cannot be examined.
Provide the examination coverage of the heat affected zone that can be examined.
- 13. Section 5.3, page 7, sixth paragraph states that " ... The UT transducers and delivery tooling are capable of scanning from the bore of the nozzles with inside diameters near 1.20 inches ... " Clarify this sentence.
The staff understands that the UT can be performed from the inside the bore but it is not clear what is meant by linear 1.20 inches." 14. Section 5.4, page 8, first paragraph stated that " ... Mock-up testing has verified that the anomalies may exist and do not exceed 0.05 inches in length ... " (1) Discuss the smallest size of indications that the UT is qualified to detect and size; (2) Describe how mock-up testing concludes that the anomaly does not exceed 0.05 inches in length; and (3) If after sleeve installation the UT detects a triple point anomaly that exceeds 0.05 inches, the proposed fracture mechanics calculation assuming a flaw size of 0.05 inches may be invalid. The relief request may also be invalid. Discuss corrective actions if the UT detects a triple point anomaly that exceeds 0.05 inches. 15. Discuss whether a full scale mock-up was or will be prepared to qualify the sleeve modification procedures, including machining, welding, and inspections.
If yes, describe the qualification of modification procedures.
If not, discuss how the sleeve modification can be ensured to achieve acceptable results. 16. Section 5.4, page 8, seventh paragraph states that " ... Based on evaluation procedures and acceptance criteria contained in Article IWB-3612 and Appendix C of ASME Section XI, results of fracture mechanics analyses demonstrate that a 0.05 inch weld anomaly in either a repaired heater sleeve or instrumentation nozzle is acceptable for a 40-year design life ... " Submit the flaw evaluation for the triple point anomaly. 17. Section 5.5, page 9. Submit the flaw evaluation of the J-groove weld between the original sleeve and pressurizer lower head nozzle penetration.
-4 18. Discuss the inservice inspection of the new sleeve and new weld, including the frequency and method. 19. Discuss the design qualification of the proposed repair or submit the design calculations and specifications.
Specifically, discuss how the new sleeve and the new weld satisfy the design requirements of the ASME Code,Section III. This discussion should explain how the new sleeve and weld support the loading so that the new sleeve and the associated heater element will not be ejected from the pressurizer penetration.
April 12, 2011 Mr. George H. Gellrich, Vice President Calvert Cliffs Nuclear Power Plant, LLC Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702 CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1, REQUEST FOR ADDITIONAL INFORMATION RE: RELIEF REQUEST NO. RR-PZR-01 FOR MODIFICATIONS TO THE PRESSURIZER HEATER SLEEVE AND LOWER LEVEL NOZZLE PENETRATIONS (TAC NO. ME5423)
Dear Mr. Gellrich:
By letter dated January 31,2011, and pursuant to Title 10 of the Code of Federal Regulations 50.55a(a)(3)(i), Calvert Cliffs Nuclear Power Plant, LLC submitted relief request number PZR-01 for Nuclear Regulatory Commission (NRC) approval.
RR-PZR-01, which is an alternative to the American Society of Mechanical Engineers Boiler and Pressure Code requirements, would permit modifications to the Calvert Cliffs Unit No. 1 pressurizer heater sleeve and lower level nozzle penetrations in order to mitigate the propensity for primary water stress-corrosion cracking from occurring.
The NRC staff has determined that additional information is needed to complete its review. The staff's request for additional information (RAI) is enclosed.
Based upon discussions with your staff, we understand that you will respond to the enclosed RAI by May 6, 2011. Please contact me at 301-415-1364 if you have any questions.
Sincerely, Ira! Douglas V. Pickett, Senior Project Manager Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-317
Enclosure:
As stated cc w/encl: Distribution via Listserv Distribution:
PUBLIC LPL1-1 r/f RidsOgcRp RidsAcrsAcnwMailCenter RidsNrrDorlLpl1-1 RidsNrrPMCalvertCliffsResource RidsNrrLASLittle RidsNrrDciCpnb GDentel. R1 JTsao. NRR/CPNB CSydnor. NRR/CPNB ADAMS Accession No. ML 110880672 OFFICE NRR/LPL 1-1/PM-1 NRR/LPL 1-1/LA NRR/CPNB/BC NRR/LPL 1-1/BC NAME DPickett SLittie TLupold by email dated NSalgado DATE 04/12111 04/11 111 03/24/11 04/12/11 OFFICIAL RECORD COPY