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| | issue date = 08/18/2015 | | | issue date = 08/18/2015 |
| | title = Requests for Additional Information for the Review of the LaSalle County Station Units 1 & 2 License Renewal Application - Set 9 (TAC Nos. MF5347 and MF5346) | | | title = Requests for Additional Information for the Review of the LaSalle County Station Units 1 & 2 License Renewal Application - Set 9 (TAC Nos. MF5347 and MF5346) |
| | author name = Mitchell J S | | | author name = Mitchell J |
| | author affiliation = NRC/NRR, NRC/NRR/DLR/RPB1 | | | author affiliation = NRC/NRR, NRC/NRR/DLR/RPB1 |
| | addressee name = Gallagher M P | | | addressee name = Gallagher M |
| | addressee affiliation = Exelon Generation Co, LLC | | | addressee affiliation = Exelon Generation Co, LLC |
| | docket = 05000373, 05000374 | | | docket = 05000373, 05000374 |
| | license number = | | | license number = |
| | contact person = Mitchell J S, NRR/DLR, 415-3019 | | | contact person = Mitchell J, NRR/DLR, 415-3019 |
| | case reference number = DLR-15-0362, TAC MF5346, TAC MF5347 | | | case reference number = DLR-15-0362, TAC MF5346, TAC MF5347 |
| | document type = Letter, Request for Additional Information (RAI) | | | document type = Letter, Request for Additional Information (RAI) |
| | page count = 7 | | | page count = 7 |
| | project = TAC:MF5346, TAC:MF5347 | | | project = TAC:MF5346, TAC:MF5347 |
| | | stage = RAI |
| }} | | }} |
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| =Text= | | =Text= |
| {{#Wiki_filter: UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 August 18, 2015 Mr. Michael P. Gallagher Vice President, License Renewal Projects Exelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348 SUBJECT: REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346) | | {{#Wiki_filter:UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 August 18, 2015 Mr. Michael P. Gallagher Vice President, License Renewal Projects Exelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348 |
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| | ==SUBJECT:== |
| | REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346) |
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| ==Dear Mr. Gallagher:== | | ==Dear Mr. Gallagher:== |
| By letter dated December 9, 2014, Exelon Generation Company, LLC (Exelon) submitted an application pursuant to Title 10 of the Code of Federal Regulations Part 54, to renew the operating licenses NPF-11 and NPF-18 for LaSalle County Station (LSCS), Units 1 and 2, respectively. The staff of the U.S. Nuclear Regulatory Commission (NRC or the staff) is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review.
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| These requests for additional information were discussed with Mr. John Hufnagel, and a mutually agreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3019 or by e-mail at Jeffrey.Mitchell2@nrc.gov. Sincerely, /RA/ | | By letter dated December 9, 2014, Exelon Generation Company, LLC (Exelon) submitted an application pursuant to Title 10 of the Code of Federal Regulations Part 54, to renew the operating licenses NPF-11 and NPF-18 for LaSalle County Station (LSCS), Units 1 and 2, respectively. The staff of the U.S. Nuclear Regulatory Commission (NRC or the staff) is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review. |
| Jeffrey S. Mitchell, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374 | | These requests for additional information were discussed with Mr. John Hufnagel, and a mutually agreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3019 or by e-mail at Jeffrey.Mitchell2@nrc.gov. |
| | Sincerely, |
| | /RA/ |
| | Jeffrey S. Mitchell, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374 |
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| ==Enclosure:== | | ==Enclosure:== |
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| As stated cc: Listserv August 18, 2015 Mr. Michael P. Gallagher Vice President, License Renewal Projects Exelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348 | | As stated cc: Listserv |
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| | August 18, 2015 Mr. Michael P. Gallagher Vice President, License Renewal Projects Exelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348 |
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| ==SUBJECT:== | | ==SUBJECT:== |
| REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346) | | REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346) |
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| ==Dear Mr. Gallagher:== | | ==Dear Mr. Gallagher:== |
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| By letter dated December 9, 2014, Exelon Generation Company, LLC (Exelon) submitted an application pursuant to Title 10 of the Code of Federal Regulations Part 54, to renew the operating licenses NPF-11 and NPF-18 for LaSalle County Station (LSCS), Units 1 and 2, respectively. The staff of the U.S. Nuclear Regulatory Commission (NRC or the staff) is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review. These requests for additional information were discussed with Mr. John Hufnagel, and a mutually agreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3019 or by e-mail at Jeffrey.Mitchell2@nrc.gov. Sincerely, /RA/ Jeffrey S. Mitchell, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374 Enclosure: | | By letter dated December 9, 2014, Exelon Generation Company, LLC (Exelon) submitted an application pursuant to Title 10 of the Code of Federal Regulations Part 54, to renew the operating licenses NPF-11 and NPF-18 for LaSalle County Station (LSCS), Units 1 and 2, respectively. The staff of the U.S. Nuclear Regulatory Commission (NRC or the staff) is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review. |
| As stated | | These requests for additional information were discussed with Mr. John Hufnagel, and a mutually agreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3019 or by e-mail at Jeffrey.Mitchell2@nrc.gov. |
| | Sincerely, |
| | /RA/ |
| | Jeffrey S. Mitchell, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374 |
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| | ==Enclosure:== |
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| | As stated cc: Listserv DISTRIBUTION: |
| | See next page ADAMS Accession Number: ML15204A630 *Concurred via e-mail OFFICE LA:DLR* PM:RPB1:DLR PM:RPB1:DLR BC:RPB1:DLR PM:RPB1:DLR NAME YEdmonds JMitchell RPlasse YDiaz-Sanabria JMitchell DATE 7/ 29 /15 7/ 31 /15 8/ 4 /15 8/ 18 /15 8/ 18 /15 OFFICIAL RECORD COPY |
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| cc: Listserv DISTRIBUTION: See next page
| | Letter to Michael P. Gallagher from Jeffrey S. Mitchell dated August 18, 2015 |
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| ADAMS Accession Number: ML15204A630 *Concurred via e-mail OFFICE LA:DLR* PM:RPB1:DLR PM:RPB1:DLR BC:RPB1:DLR PM:RPB1:DLR NAME YEdmonds JMitchell RPlasse YDiaz-Sanabria JMitchell DATE 7/ 29 /15 7/ 31 /15 8/ 4 /15 8/ 18 /15 8/ 18 /15 OFFICIAL RECORD COPY Letter to Michael P. Gallagher from Jeffrey S. Mitchell dated August 18, 2015 SUBJECT: REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346)
| | ==SUBJECT:== |
| DISTRIBUTION: E-MAIL: PUBLIC RidsNrrDlr Resource RidsNrrDlrRpb1 Resource RidsNrrDlrRpb2 Resource RidsNrrDlrRerb Resource RidsNrrDlrRarb Resource RidsNrrDlrRasb Resource RidsNrrDlrRsrg Resource RidsNrrPMLaSalle Resource
| | REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346) |
| --------------- J. Mitchell R. Plasse D. Drucker J. Danna J. Wachutka, OGC D. McIntyre, OPA M. Kunowski, RIII V. Mitlyng, RIII P. Chandrathil, RIII H. Logaras, RIII C. Lipa, RIII S. Sheldon, RIII R. Ruiz, RIII J. Robbins, RIII ENCLOSURE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION REQUESTS FOR ADDITIONAL INFORMATION - SET 9 (TAC NOS. MF5347 AND MF5346) RAI B.2.1.7-3a Background: By letter dated June 25, 2015, the applicant responded to request for additional information (RAI) B.2.1.7-3 that addressed limited examination coverage for Generic Letter (GL) 88-01 welds. In its response, the applicant assessed a time period (February 2008 through March 2015) to evaluate the limited examination coverage of the welds within the scope of the BWR Stress Corrosion Cracking program. The applicant indicated that during the assessed period (February 2008 through March 2015) none of the Unit 1 Category A welds and Unit 2 Category C welds were inspected. The applicant also indicated that there are only two Category D welds at Unit 2. The applicant further indicated that the examination coverage for each of the welds was limited to 50 percent because each weld is between pipe and a cast valve body where the current approved Performance Demonstration Initiative (PDI) method does not provide qualified and reliable results for the side of the weld adjacent to the cast valve body due to the specific contour of the valve body. Issue: As described in the background section, the response did not provide information regarding the examination coverage of Unit 1 Category A welds and Unit 2 Category C welds. The staff needs information on examination coverage of these welds based on previous inspection results in order to resolve the concern related to limited examination coverage. The staff also needs additional information to evaluate the applicant's justification for the limited examination coverage of the Unit 2 Category D welds. It is unclear whether the cast valve bodies associated with the Unit 2 Category D welds are made of cast materials resistant to intergranular stress corrosion cracking (IGSCC). In addition, the staff needs to confirm whether inspection results for the cast valve bodies indicate occurrence of IGSCC. Request: 1. Provide information on the average examination coverage of Unit 1 Category A welds and Unit 2 Category C welds to characterize the overall degree of limited examination coverage. If limited examination coverage is identified for these welds, provide justification for why additional inspections are not necessary to compensate for the limited examination coverage of these welds.
| | DISTRIBUTION: |
| - 2 - 2. Provide the following information regarding the cast valve bodies associated with the two Category D welds at Unit 2: a) Cast material grade (e.g., CF3M), carbon content, and ferrite content (including the method for determining ferrite content) of the cast valve bodies to clarify whether the materials are resistant to IGSCC in accordance with the staff positions in GL 88-01 b) American Society of Mechanical Engineers (ASME) Code Class and, if available, examination results of the cast valve bodies such as internal visual or surface examination results per ASME Code Section XI requirements RAI 4.2.1-1 Background: License Renewal Application (LRA) Section 4.2.1 describes the applicant's time-limited aging analysis (TLAA) on reactor vessel fluence calculations. LRA Section 4.2.1 also indicates that the 54-effective full power year (EFPY) fluence projections for 60 years of operation were calculated by using the NRC-approved Radiation Analysis Modeling Application (RAMA) methodology. The LRA further states that the 54-EFPY fluence projections compile the cumulative fluence resulting from each past operating cycle and add the predicted fluence estimate for future operating cycles through the period of extended operation. As discussed below, the NRC staff noted that these 54-EFPY fluence projections are independent from the fluence projections used in the current P-T limits. LRA Section 4.2.1 states that the neutron fluence projections used as inputs to the current 40-year neutron embrittlement analyses for LSCS, Units 1 and 2 were developed in accordance with GE Licensing Topical Report NEDO-32983, "General Electric Methodology for Reactor Pressure Vessel Fast Neutron Flux Evaluations," (ADAMS Accession No. ML072480121). LRA Section 4.2.1 also indicated that this GE methodology is in compliance with NRC Regulatory Guide 1.190, as approved by the NRC staff in the safety evaluation dated September 14, 2001. Under LRA Section 4.2.1, the TLAA evaluation states that the 60-year RAMA neutron fluence projections compile the cumulative neutron fluence resulting from each past operating cycle and add the predicted neutron fluence estimated for future operating cycles through the period of extended operation. The RAMA neutron fluence projections are prepared using the BWRVIP-126 methodology. These 60-year neutron fluence projections are independent from the neutron fluence projections used with the current P-T curve submittals. In comparison, the following reference indicates that the current 40-year (32-EFPY) P-T limits for LSCS Unit 1 use neutron fluence values that are calculated via the RAMA fluence methodology.
| | E-MAIL: |
| * NRC Safety Evaluation, "LaSalle County Station, Unit 1, Issuance of Amendment Revising Pressure and Temperature Limits (TAC No. MF3270)," dated November 25, 2014 (ADAMS Accession No. ML14220A517). | | PUBLIC RidsNrrDlr Resource RidsNrrDlrRpb1 Resource RidsNrrDlrRpb2 Resource RidsNrrDlrRerb Resource RidsNrrDlrRarb Resource RidsNrrDlrRasb Resource RidsNrrDlrRsrg Resource RidsNrrPMLaSalle Resource |
| - 3 - Section 3.1, Neutron Fluence Calculation, of the above reference states that the safety evaluation shall not be constructed as endorsement, agreement with, or approval of, the position regarding the combined use of neutron fluence methods to determine a total neutron fluence. Issue: The LRA does not address the RAMA methodology that the NRC staff evaluated in the safety evaluation regarding the current P-T limits for LSCS, Unit 1. Therefore, the NRC staff needs additional clarification as to the specific neutron fluence methodology that is used in the license renewal TLAAs. It is also unclear to the NRC staff how the applicant evaluates potential effects of updated neutron fluence calculation on existing neutron embrittlement analysis. Request: 1. Clarify whether the 54-EFPY neutron fluences described in the LRA are based on the GE methodology, the RAMA methodology, or the combination of the two methodologies. 2. Clarify how the applicant will ensure that the actual fluence levels are bounded by the fluence levels analyzed in LRA Section 4.2.1. RAI 4.2.8-1 Background: LRA Section 4.2.8 describes the TLAA for the loss of preload of the reactor pressure vessel (RPV) core plate rim hold-down bolts resulting from irradiation effects. The LRA states that a fluence evaluation based on 54 EFPY has identified the bolts with the highest fluence values after 60 years of operation for Unit 1 (3.60x1019 n/cm2) and Unit 2 (3.85x1019 n/cm2). The LRA also states that an average fluence value of 8.0x1019 n/cm2 was evaluated for 40 years of operation which resulted in a maximum relaxation of 19 percent in preload for the RPV core plate rim hold-down bolts. The TLAA is dispositioned in accordance with 10 CFR 54.21(c)(1)(i) to remain valid through the period of extended operation. The loss of preload analysis was performed as part of Boiling Water Reactor Vessel and Internals Project Technical Report 25 (BWRVIP-25), "BWR Core Plate Inspection and Flaw Evaluation Guidelines." Section 2.1.3 of BWRVIP-25 states that it has been determined that a 5 percent to 19 percent reduction in preload is expected over a 40-year operating experience and that the bolts will maintain some amount of preload throughout the life of the plant. Section B.4 of Appendix B states that the loss of preload was recalculated based on 60 years of plant operation and that the reduction in preload remains 5 percent to 19 percent. Issue: The staff is unable to determine if the amount of relaxation experienced after 60 years of operation is bounded by the 40-year analyses because the fluence values used to determine the range in percent reduction of preload are not provided in BWRVIP-25 or the appendixes of the report.
| | --------------- |
| - 4 - Request: Provide the analysis used to determine that an average fluence value of 8.0x1019 n/cm2 produces a maximum relaxation of 19 percent in preload for the RPV core plate rim hold-down bolts. Justify that the analysis adequately considers plant-specific configurations of reactor vessel internals and is bounded by the relaxation evaluations in BWRVIP-25. RAI 4.2.10-1 Background: Section 4.7.3.1.3 of the SRP-LR (NUREG-1800, Rev. 2) provides the NRC's review procedures for plant-specific TLAAs which will be managed in accordance with 10 CFR 54.21(c)(1)(iii).
| | J. Mitchell R. Plasse D. Drucker J. Danna J. Wachutka, OGC D. McIntyre, OPA M. Kunowski, RIII V. Mitlyng, RIII P. Chandrathil, RIII H. Logaras, RIII C. Lipa, RIII S. Sheldon, RIII R. Ruiz, RIII J. Robbins, RIII |
| SRP-LR Section 4.7.3.1.3 states that the staff is to review the aging management program proposed by the applicant to verify the program is adequate to manage the aging effects associated with the TLAA. LRA Section 4.2.10 describes the TLAA evaluation for the loss of preload of the jet pump slip joint repair clamp. LRA Section 4.2.10 dispositions the TLAA in accordance with 10 CFR 54.21(c)(1)(iii) to be managed by Commitment No. 47 in LRA Section A.5. This commitment states that: Prior to exceeding the limiting fluence value of 1.17x1020 n/cm2 at the Unit 1 jet pump slip joint clamp location, estimated to be at 50.7 EFPY, revise the analysis for the slip joint clamps for a higher acceptable fluence value or take other corrective action such as repair or replacement of the clamps to ensure acceptable clamp preload. The implementation schedule for Commitment No. 47 is "Prior to the period of extended operation." Issue: The LRA does not clearly identify how the applicant will ensure that the limiting fluence value is not exceeded. The staff is unable to determine if the applicant's program or activities are adequate to ensure that the limiting fluence value is not exceeded. Request: Identify the program or a set of activities that will be used for the jet pump slip joint repair clamp to ensure that the limiting fluence value is not exceeded. Justify that the program or activities are adequate for managing the aging effect of loss of preload of the jet pump slip joint repair clamp. | | |
| }} | | LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION REQUESTS FOR ADDITIONAL INFORMATION - SET 9 (TAC NOS. MF5347 AND MF5346) |
| | RAI B.2.1.7-3a |
| | |
| | ==Background:== |
| | |
| | By letter dated June 25, 2015, the applicant responded to request for additional information (RAI) B.2.1.7-3 that addressed limited examination coverage for Generic Letter (GL) 88-01 welds. In its response, the applicant assessed a time period (February 2008 through March 2015) to evaluate the limited examination coverage of the welds within the scope of the BWR Stress Corrosion Cracking program. The applicant indicated that during the assessed period (February 2008 through March 2015) none of the Unit 1 Category A welds and Unit 2 Category C welds were inspected. |
| | The applicant also indicated that there are only two Category D welds at Unit 2. The applicant further indicated that the examination coverage for each of the welds was limited to 50 percent because each weld is between pipe and a cast valve body where the current approved Performance Demonstration Initiative (PDI) method does not provide qualified and reliable results for the side of the weld adjacent to the cast valve body due to the specific contour of the valve body. |
| | Issue: |
| | As described in the background section, the response did not provide information regarding the examination coverage of Unit 1 Category A welds and Unit 2 Category C welds. The staff needs information on examination coverage of these welds based on previous inspection results in order to resolve the concern related to limited examination coverage. |
| | The staff also needs additional information to evaluate the applicants justification for the limited examination coverage of the Unit 2 Category D welds. It is unclear whether the cast valve bodies associated with the Unit 2 Category D welds are made of cast materials resistant to intergranular stress corrosion cracking (IGSCC). In addition, the staff needs to confirm whether inspection results for the cast valve bodies indicate occurrence of IGSCC. |
| | Request: |
| | : 1. Provide information on the average examination coverage of Unit 1 Category A welds and Unit 2 Category C welds to characterize the overall degree of limited examination coverage. If limited examination coverage is identified for these welds, provide justification for why additional inspections are not necessary to compensate for the limited examination coverage of these welds. |
| | ENCLOSURE |
| | : 2. Provide the following information regarding the cast valve bodies associated with the two Category D welds at Unit 2: |
| | a) Cast material grade (e.g., CF3M), carbon content, and ferrite content (including the method for determining ferrite content) of the cast valve bodies to clarify whether the materials are resistant to IGSCC in accordance with the staff positions in GL 88-01 b) American Society of Mechanical Engineers (ASME) Code Class and, if available, examination results of the cast valve bodies such as internal visual or surface examination results per ASME Code Section XI requirements RAI 4.2.1-1 |
| | |
| | ==Background:== |
| | |
| | License Renewal Application (LRA) Section 4.2.1 describes the applicants time-limited aging analysis (TLAA) on reactor vessel fluence calculations. LRA Section 4.2.1 also indicates that the 54-effective full power year (EFPY) fluence projections for 60 years of operation were calculated by using the NRC-approved Radiation Analysis Modeling Application (RAMA) methodology. The LRA further states that the 54-EFPY fluence projections compile the cumulative fluence resulting from each past operating cycle and add the predicted fluence estimate for future operating cycles through the period of extended operation. As discussed below, the NRC staff noted that these 54-EFPY fluence projections are independent from the fluence projections used in the current P-T limits. |
| | LRA Section 4.2.1 states that the neutron fluence projections used as inputs to the current 40-year neutron embrittlement analyses for LSCS, Units 1 and 2 were developed in accordance with GE Licensing Topical Report NEDO-32983, General Electric Methodology for Reactor Pressure Vessel Fast Neutron Flux Evaluations, (ADAMS Accession No. ML072480121). LRA Section 4.2.1 also indicated that this GE methodology is in compliance with NRC Regulatory Guide 1.190, as approved by the NRC staff in the safety evaluation dated September 14, 2001. |
| | Under LRA Section 4.2.1, the TLAA evaluation states that the 60-year RAMA neutron fluence projections compile the cumulative neutron fluence resulting from each past operating cycle and add the predicted neutron fluence estimated for future operating cycles through the period of extended operation. The RAMA neutron fluence projections are prepared using the BWRVIP-126 methodology. These 60-year neutron fluence projections are independent from the neutron fluence projections used with the current P-T curve submittals. |
| | In comparison, the following reference indicates that the current 40-year (32-EFPY) P-T limits for LSCS Unit 1 use neutron fluence values that are calculated via the RAMA fluence methodology. |
| | * NRC Safety Evaluation, LaSalle County Station, Unit 1, Issuance of Amendment Revising Pressure and Temperature Limits (TAC No. MF3270), dated November 25, 2014 (ADAMS Accession No. ML14220A517). |
| | |
| | Section 3.1, Neutron Fluence Calculation, of the above reference states that the safety evaluation shall not be constructed as endorsement, agreement with, or approval of, the position regarding the combined use of neutron fluence methods to determine a total neutron fluence. |
| | Issue: |
| | The LRA does not address the RAMA methodology that the NRC staff evaluated in the safety evaluation regarding the current P-T limits for LSCS, Unit 1. Therefore, the NRC staff needs additional clarification as to the specific neutron fluence methodology that is used in the license renewal TLAAs. It is also unclear to the NRC staff how the applicant evaluates potential effects of updated neutron fluence calculation on existing neutron embrittlement analysis. |
| | Request: |
| | : 1. Clarify whether the 54-EFPY neutron fluences described in the LRA are based on the GE methodology, the RAMA methodology, or the combination of the two methodologies. |
| | : 2. Clarify how the applicant will ensure that the actual fluence levels are bounded by the fluence levels analyzed in LRA Section 4.2.1. |
| | RAI 4.2.8-1 |
| | |
| | ==Background:== |
| | |
| | LRA Section 4.2.8 describes the TLAA for the loss of preload of the reactor pressure vessel (RPV) core plate rim hold-down bolts resulting from irradiation effects. The LRA states that a fluence evaluation based on 54 EFPY has identified the bolts with the highest fluence values after 60 years of operation for Unit 1 (3.60x1019 n/cm2) and Unit 2 (3.85x1019 n/cm2). The LRA also states that an average fluence value of 8.0x1019 n/cm2 was evaluated for 40 years of operation which resulted in a maximum relaxation of 19 percent in preload for the RPV core plate rim hold-down bolts. The TLAA is dispositioned in accordance with 10 CFR 54.21(c)(1)(i) to remain valid through the period of extended operation. |
| | The loss of preload analysis was performed as part of Boiling Water Reactor Vessel and Internals Project Technical Report 25 (BWRVIP-25), BWR Core Plate Inspection and Flaw Evaluation Guidelines. Section 2.1.3 of BWRVIP-25 states that it has been determined that a 5 percent to 19 percent reduction in preload is expected over a 40-year operating experience and that the bolts will maintain some amount of preload throughout the life of the plant. Section B.4 of Appendix B states that the loss of preload was recalculated based on 60 years of plant operation and that the reduction in preload remains 5 percent to 19 percent. |
| | Issue: |
| | The staff is unable to determine if the amount of relaxation experienced after 60 years of operation is bounded by the 40-year analyses because the fluence values used to determine the range in percent reduction of preload are not provided in BWRVIP-25 or the appendixes of the report. |
| | |
| | Request: |
| | Provide the analysis used to determine that an average fluence value of 8.0x1019 n/cm2 produces a maximum relaxation of 19 percent in preload for the RPV core plate rim hold-down bolts. Justify that the analysis adequately considers plant-specific configurations of reactor vessel internals and is bounded by the relaxation evaluations in BWRVIP-25. |
| | RAI 4.2.10-1 |
| | |
| | ==Background:== |
| | |
| | Section 4.7.3.1.3 of the SRP-LR (NUREG-1800, Rev. 2) provides the NRCs review procedures for plant-specific TLAAs which will be managed in accordance with 10 CFR 54.21(c)(1)(iii). |
| | SRP-LR Section 4.7.3.1.3 states that the staff is to review the aging management program proposed by the applicant to verify the program is adequate to manage the aging effects associated with the TLAA. |
| | LRA Section 4.2.10 describes the TLAA evaluation for the loss of preload of the jet pump slip joint repair clamp. LRA Section 4.2.10 dispositions the TLAA in accordance with 10 CFR 54.21(c)(1)(iii) to be managed by Commitment No. 47 in LRA Section A.5. This commitment states that: |
| | Prior to exceeding the limiting fluence value of 1.17x1020 n/cm2 at the Unit 1 jet pump slip joint clamp location, estimated to be at 50.7 EFPY, revise the analysis for the slip joint clamps for a higher acceptable fluence value or take other corrective action such as repair or replacement of the clamps to ensure acceptable clamp preload. |
| | The implementation schedule for Commitment No. 47 is Prior to the period of extended operation. |
| | Issue: |
| | The LRA does not clearly identify how the applicant will ensure that the limiting fluence value is not exceeded. The staff is unable to determine if the applicants program or activities are adequate to ensure that the limiting fluence value is not exceeded. |
| | Request: |
| | Identify the program or a set of activities that will be used for the jet pump slip joint repair clamp to ensure that the limiting fluence value is not exceeded. Justify that the program or activities are adequate for managing the aging effect of loss of preload of the jet pump slip joint repair clamp.}} |
Letter Sequence RAI |
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TAC:MF5346, Control Room Habitability (Approved, Closed) TAC:MF5347, Control Room Habitability (Approved, Closed) |
Results
Other: ML15104A782, ML15196A045, ML15196A115, ML16202A033, RS-15-193, Responds to NRC Requests for Additional Information, Set 5, Dated July 7, 2015 Related to the License Renewal Application, RS-15-194, Responds to NRC Requests for Additional Information, Set 6, Dated July 7, 2015 Related to the License Renewal Application, RS-15-305, Corrections to the License Renewal Application Dated December 9, 2014, RS-15-306, Submittal of 10 CFR 54.21(b) Annual Amendment to the License Renewal Application, RS-16-033, Update to Commitment 47 Related to the License Renewal Application, RS-16-068, Comments on the Safety Evaluation Report with Open Items, Related to the License Renewal Application, RS-16-128, Second 10 CFR 54.21(b) Annual Amendment to the License Renewal Application
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MONTHYEARML15104A7822015-05-0808 May 2015
Scoping and Screening Methodology Audit Report Regarding LaSalle County Station, Units 1 and 2
Project stage: Other
ML15111A1372015-05-14014 May 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application - Set 1 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15125A1982015-05-29029 May 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application - Set 2 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15131A4132015-06-0808 June 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application - Set 3 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15140A1922015-06-0808 June 2015
Summary of Telephone Conference Call Held on May 13, 2015, Between the U.S. Nuclear Regulatory Commission and Exelon Generation Co., LLC, Concerning Requests for Additional Information, Set 2 Pertaining to the Lasalle County Station License
Project stage: RAI
ML15146A2622015-06-19019 June 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application-Set 4 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
RS-15-165, Response to NRC Requests for Additional Information, Set 2, Dated May 29, 2015 Related to the License Renewal Application2015-06-25025 June 2015
Response to NRC Requests for Additional Information, Set 2, Dated May 29, 2015 Related to the License Renewal Application
Project stage: Response to RAI
RS-15-171, Response to NRC Requests for Additional Information, Set 3, Dated June 8, 2015, Related to the License Renewal Application2015-07-0101 July 2015
Response to NRC Requests for Additional Information, Set 3, Dated June 8, 2015, Related to the License Renewal Application
Project stage: Response to RAI
ML15159A9002015-07-0606 July 2015
Telephone Conference Call Held on May 20, 2015, Between the U.S. Nuclear Regulatory Commission and Exelon Generation Co., LLC, Requests for Additional Information, Set 3 Pertaining to the LaSalle County Station License Renewal Application (
Project stage: RAI
ML15163A0712015-07-0707 July 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application - Set 6 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15159A2082015-07-0707 July 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application - Set 5 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
RS-15-180, Response to NRC Requests for Additional Information, Set 4, Dated June 19, 2015 Related to the License Renewal Application2015-07-15015 July 2015
Response to NRC Requests for Additional Information, Set 4, Dated June 19, 2015 Related to the License Renewal Application
Project stage: Response to RAI
RS-15-198, Request for Schedule Change Related to Advisory Committee on Reactor Safeguards (ACRS) Subcommittee Review of License Renewal Application (TAC Nos. MF5347 and MF5346)2015-07-16016 July 2015
Request for Schedule Change Related to Advisory Committee on Reactor Safeguards (ACRS) Subcommittee Review of License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: Request
ML15196A5292015-07-27027 July 2015
Requests for Additional Information for the Review of the Lasalle County Station, Units 1 and 2 License Renewal Application - Set 7 (Tac Nos. MF5347 and MF5346)
Project stage: RAI
RS-15-194, Responds to NRC Requests for Additional Information, Set 6, Dated July 7, 2015 Related to the License Renewal Application2015-08-0606 August 2015
Responds to NRC Requests for Additional Information, Set 6, Dated July 7, 2015 Related to the License Renewal Application
Project stage: Other
RS-15-193, Responds to NRC Requests for Additional Information, Set 5, Dated July 7, 2015 Related to the License Renewal Application2015-08-0606 August 2015
Responds to NRC Requests for Additional Information, Set 5, Dated July 7, 2015 Related to the License Renewal Application
Project stage: Other
ML15204A6302015-08-18018 August 2015
Requests for Additional Information for the Review of the LaSalle County Station Units 1 & 2 License Renewal Application - Set 9 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
RS-15-223, Response to NRC Requests for Additional Information, Set 7, Dated July 27, 2015; and a Correction to Information Associated with the Set 2 Response to RAI 8.2.1.20-2, Related to the Renewal Application2015-08-26026 August 2015
Response to NRC Requests for Additional Information, Set 7, Dated July 27, 2015; and a Correction to Information Associated with the Set 2 Response to RAI 8.2.1.20-2, Related to the Renewal Application
Project stage: Response to RAI
ML15229A0192015-08-27027 August 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application - Set 10 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15217A5412015-08-28028 August 2015
June 9, 2015, Summary of Telecon Held Between the NRC and Exelon Generation Co., LLC, Concerning Request for Additional Information Set 5 Pertaining to the LaSalle County Station License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15217A5642015-08-28028 August 2015
June 3, 2015, Summary of Telecon Held Between the NRC and Exelon Generation Co., LLC, Concerning Request for Additional Information Set 4 Pertaining to the LaSalle County Station License Renewal Application (Tac Nos. MF5347 and MF5346)
Project stage: RAI
ML15217A5752015-08-28028 August 2015
June 10, 2015, Summary of Telecon Held Between the NRC and Exelon Generation Co., LLC, Concerning Request for Additional Information Set 4 Pertaining to the LaSalle County Station License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15219A2772015-08-28028 August 2015
June 23, 2015, Summary of Telecon Held Between the NRC and Exelon Generation Co., LLC, Concerning Request for Additional Information Set 6 Pertaining to the LaSalle County Station License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15222A0062015-08-28028 August 2015
August 5, 2015, Summary of Telecon Held Between the NRC and Exelon Generation Co., LLC, Concerning Request for Additional Information Set 9 Pertaining to the LaSalle County Station License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15195A3382015-08-28028 August 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application-Set 8 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15222A0082015-08-28028 August 2015
July 22, 2015, Summary of Telecon Held Between the NRC and Exelon Generation Co., LLC, Concerning Request for Additional Information Set 8 Pertaining to the LaSalle County Station License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15222A0152015-08-28028 August 2015
July 8, 2015, Summary of Telecon Held Between the NRC and Exelon Generation Co., LLC, Concerning Request for Additional Information Set 7 Pertaining to the LaSalle County Station License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15224A9352015-08-28028 August 2015
August 11, 2015, Summary of Telecon Held Between the NRC and Exelon Generation Co., LLC, Concerning Request for Additional Information Set 9 Pertaining to the LaSalle County Station License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15244B3532015-09-14014 September 2015
RAI for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application - Set 11 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
RS-15-232, Response to NRC Requests for Additional Information, Set 9, Dated August 18, 2015 Related to the License Renewal Application2015-09-15015 September 2015
Response to NRC Requests for Additional Information, Set 9, Dated August 18, 2015 Related to the License Renewal Application
Project stage: Response to RAI
RS-15-238, Response to NRC Requests for Additional Information, Set 10, Dated August 27, 2015 Related to License Renewal Application2015-09-17017 September 2015
Response to NRC Requests for Additional Information, Set 10, Dated August 27, 2015 Related to License Renewal Application
Project stage: Response to RAI
ML15196A1152015-09-22022 September 2015
Aging Management Programs Audit Report Regarding Lasalle County Station, Units 1 and 2,
Project stage: Other
ML15196A0452015-09-22022 September 2015
Aging Management Programs Audit Report Regarding Lasalle County Station, Units 1 and 2, (TAC Nos. MF5347 and MF5346). Cover Letter
Project stage: Other
RS-15-239, Response to NRC Requests for Additional Information, Set 8, Dated August 28, 2015 Related to the License Renewal Application2015-09-28028 September 2015
Response to NRC Requests for Additional Information, Set 8, Dated August 28, 2015 Related to the License Renewal Application
Project stage: Response to RAI
RS-15-256, Response to NRC Request for Additional Information, Set 11, Dated September 14, 2015 Related to the License Renewal Application2015-10-0808 October 2015
Response to NRC Request for Additional Information, Set 11, Dated September 14, 2015 Related to the License Renewal Application
Project stage: Response to RAI
ML15208A0522015-10-22022 October 2015
Schedule Revision for the Review of the Lasalle County Station License Renewal Application (TAC Nos. MF5347 & MF5346)
Project stage: Approval
ML15271A0212015-10-23023 October 2015
Requests for Additional Information for the Review of the Lasalle County Station, Units 1 and 2 License Renewal Application-Set 12 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
RS-15-281, Response to NRC Requests for Additional Information, Set 12, Dated October 23, 2015 Related to the License Renewal Application2015-10-29029 October 2015
Response to NRC Requests for Additional Information, Set 12, Dated October 23, 2015 Related to the License Renewal Application
Project stage: Response to RAI
ML15300A3662015-11-0303 November 2015
Requests for Additional Information for the Review of the LaSalle County Station, Units 1 and 2 License Renewal Application - Set 13 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
RS-15-305, Corrections to the License Renewal Application Dated December 9, 20142015-12-0202 December 2015
Corrections to the License Renewal Application Dated December 9, 2014
Project stage: Other
RS-15-306, Submittal of 10 CFR 54.21(b) Annual Amendment to the License Renewal Application2015-12-0202 December 2015
Submittal of 10 CFR 54.21(b) Annual Amendment to the License Renewal Application
Project stage: Other
RS-15-292, Response to NRC Requests for Additional Information, Set 13, Dated November 3, 2015 Related to the License Renewal Application2015-12-10010 December 2015
Response to NRC Requests for Additional Information, Set 13, Dated November 3, 2015 Related to the License Renewal Application
Project stage: Response to RAI
ML15272A4002015-12-11011 December 2015
Summary of Teleconference Held on September 24, 2015, Between the NRC and Exelon Generation Co., LLC, Concerning RAI Set 10 Response Pertaining to the LaSalle County Station License Renewal Application (TAC Nos. MF5347 and MF5346)
Project stage: RAI
ML15301A1892015-12-14014 December 2015
Request for Additional Information for the Review of the LaSalle County Station, Units 1 & 2 License Renewal Application - Set 14 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
RS-16-003, Responses to NRC Requests for Additional Information, Set 14, Dated December 14, 2015, and Two Additional Commitment Implementation Schedule Clarifications, Related to the License Renewal Application2016-01-0707 January 2016
Responses to NRC Requests for Additional Information, Set 14, Dated December 14, 2015, and Two Additional Commitment Implementation Schedule Clarifications, Related to the License Renewal Application
Project stage: Response to RAI
ML15357A2812016-01-0707 January 2016
Summary of Teleconference Held on December 22, 2015, Between the NRC and Exelon Generation Co., LLC, Concerning the LaSalle County Station License Renewal Application (Tac Nos. MF5347 and MF5346)
Project stage: Meeting
RS-16-007, Supplemental Information Associated with Implementation of BWRVIP-25, Core Plate Inspection and Flaw Evaluation Guidelines, Related to the License Renewal Application2016-01-14014 January 2016
Supplemental Information Associated with Implementation of BWRVIP-25, Core Plate Inspection and Flaw Evaluation Guidelines, Related to the License Renewal Application
Project stage: Supplement
ML16021A3252016-01-29029 January 2016
Summary of Teleconference Held on January 21, 2016, Between the NRC and Exelon Generation Co., LLC, Concerning RAI 4.2.10-1 Response
Project stage: RAI
RS-16-033, Update to Commitment 47 Related to the License Renewal Application2016-02-0101 February 2016
Update to Commitment 47 Related to the License Renewal Application
Project stage: Other
ML15344A3542016-02-16016 February 2016
Requests for Additional Information for the Review of the Lasalle County, Units 1 and 2 License Renewal Application Set 15 (TAC Nos. MF5347 and MF5346)
Project stage: RAI
2015-07-16
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Category:Letter
MONTHYEARRS-24-093, Response to Request for Additional Information - Alternative Request to Utilize Code Case OMN-32, Alternative Requirements for Range and Accuracy of Pressure, Flow, and Differential Pressure Instruments Used in Pump Tests2024-10-10010 October 2024
Response to Request for Additional Information - Alternative Request to Utilize Code Case OMN-32, Alternative Requirements for Range and Accuracy of Pressure, Flow, and Differential Pressure Instruments Used in Pump Tests
05000373/LER-2023-001-01, Air Circuit Breaker (Acb) Mechanically Operated Contacts (MOC) Switch Failed to Actuate2024-10-0909 October 2024
Air Circuit Breaker (Acb) Mechanically Operated Contacts (MOC) Switch Failed to Actuate
ML24275A2442024-10-0303 October 2024
Reassignment of the U.S. Nuclear Regulatory Commission Branch Chief, Division of Operating Reactor Licensing
IR 05000373/20244012024-09-27027 September 2024
County Station – Security Baseline Inspection Report 05000373/2024401 and 05000374/2024401
ML24263A2062024-09-19019 September 2024
Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 for LaSalle County Station - Holtec MPC-68MCBS
ML24260A0492024-09-16016 September 2024
Operator Licensing Examination Approval - Lasalle County Station, Unit 1 and 2, September 2024
RS-24-090, Response to Request for Additional Information - Relief Request Concerning Extension of Permanent Relief from Ultrasonic Examination of Reactor Pressure Vessel Circumferential Shell Welds2024-09-12012 September 2024
Response to Request for Additional Information - Relief Request Concerning Extension of Permanent Relief from Ultrasonic Examination of Reactor Pressure Vessel Circumferential Shell Welds
ML24255A8642024-09-0606 September 2024
Rscc Wire & Cable LLC Dba Marmon Industrial Energy & Infrastructure - Part 21 Retraction of Final Notification
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
IR 05000373/20240052024-08-29029 August 2024
Updated Inspection Plan and Assessment Follow-Up Letter for Lasalle County Station (Report 05000373/2024005; 05000374/2024005)
IR 05000373/20244022024-08-28028 August 2024
County Station - Cyber Security Inspection Report 05000373/2024402 and 05000374/2024402
ML24239A3972024-08-23023 August 2024
Rssc Wire & Cable LLC Dba Marmon - Part 21 Final Notification - 57243-EN 57243
05000373/LER-2024-004-01, Emergency Diesel Generator Auto-Start and Load Due to Loss of System Auxiliary Transformer2024-08-22022 August 2024
Emergency Diesel Generator Auto-Start and Load Due to Loss of System Auxiliary Transformer
IR 05000373/20240022024-08-13013 August 2024
County Station - Integrated Inspection Report 05000373/2024002 and 05000374/2024002
ML24222A6772024-08-0909 August 2024
Response to Request for Additional Information for Application to Revise Technical Specifications to Adopt TSTF-591-A, Revise Risk Informed Completion Time (RICT) Program Revision 0 and Revise 10 CFR 50.69 License Condition
IR 05000373/20244202024-08-0505 August 2024
County Station - Security Baseline Inspection Report 05000373 2024420 and 05000374 2024420
05000373/LER-2024-003, Supplement to Technical Specification (TS) Limiting Condition for Operation (LCO) 3.6.1.3 Completion Time Exceeded2024-07-31031 July 2024
Supplement to Technical Specification (TS) Limiting Condition for Operation (LCO) 3.6.1.3 Completion Time Exceeded
ML24208A0962024-07-25025 July 2024
57243-EN 57243 - Rssc Wire & Cable LLC, Dba Marmon - Part 21 Notification
RS-24-064, Nuclear Radiological Emergency Plan Document Revisions2024-06-28028 June 2024
Nuclear Radiological Emergency Plan Document Revisions
ML24178A2522024-06-27027 June 2024
County Station – Acknowledgement of Response to NRC Inspection Report 05000373/2024001 and 05000374/2024001 and Disputed Non-Cited Violation
RS-24-061, Constellation Energy Generation, LLC, Response to NRC Regulatory Issue Summary 2024-01, Preparation and Scheduling of Operator Licensing Examinations2024-06-14014 June 2024
Constellation Energy Generation, LLC, Response to NRC Regulatory Issue Summary 2024-01, Preparation and Scheduling of Operator Licensing Examinations
IR 05000373/20240102024-05-29029 May 2024
County Station - Commercial Grade Dedication Inspection Report 05000373/2024010 and 05000374/2024010
ML24079A0762024-05-23023 May 2024
Issuance of Amendments to Adopt TSTF 264
ML24142A3352024-05-21021 May 2024
Quad Cities—Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes
RS-24-055, 2023 Corporate Regulatory Commitment Change Summary Report2024-05-17017 May 2024
2023 Corporate Regulatory Commitment Change Summary Report
ML24131A1512024-05-13013 May 2024
County Station - Integrated Report 05000373/2024001 and 05000374/2024001
IR 05000373/20240012024-05-13013 May 2024
County Station - Integrated Report 05000373/2024001 and 05000374/2024001
RS-24-038, Relief Request Concerning Extension of Permanent Relief from Ultrasonic Examination of Reactor Pressure Vessel Circumferential Shell Welds2024-05-0202 May 2024
Relief Request Concerning Extension of Permanent Relief from Ultrasonic Examination of Reactor Pressure Vessel Circumferential Shell Welds
RS-24-041, Alternative Request to Utilize Code Case OMN-32, Alternative Requirements for Range and Accuracy of Pressure, Flow, and Differential Pressure Instruments Used in Pump Tests2024-04-30030 April 2024
Alternative Request to Utilize Code Case OMN-32, Alternative Requirements for Range and Accuracy of Pressure, Flow, and Differential Pressure Instruments Used in Pump Tests
ML24108A1562024-04-15015 April 2024
Updated Final Safety Analysis Report (Ufsar), Revision 26 and Fire Protection Report (Fpr), Revision 11
ML24103A2042024-04-12012 April 2024
Constellation Energy Generation, LLC, Application to Revise Technical Specifications to Adopt TSTF-591-A, Revise Risk Informed Completion Time (RICT) Program Revision 0 and Revise 10 CFR 50.69 License Condition
RS-24-002, Constellation Energy Generation, LLC - Annual Property Insurance Status Report2024-04-0101 April 2024
Constellation Energy Generation, LLC - Annual Property Insurance Status Report
ML24071A2122024-03-12012 March 2024
County Station - Information Request for the Cyber-Security Baseline Inspection, Notification to Perform Inspection
IR 05000373/20230062024-02-28028 February 2024
Annual Assessment Letter for Lasalle County Station, Units 1 and 2 (Report 05000373/2023006; 05000374/2023006)
RS-24-014, Annual 10 CFR 50.46 Report of Emergency Core Cooling System Evaluation Model Changes and Errors2024-02-22022 February 2024
Annual 10 CFR 50.46 Report of Emergency Core Cooling System Evaluation Model Changes and Errors
ML24018A0682024-02-0909 February 2024
Issuance of Amendment Nos. 262 and 247 Revised Design Bases of Lower Downcomer Braces
ML24024A1332024-01-24024 January 2024
Confirmation of Initial License Examination
IR 05000373/20230042024-01-24024 January 2024
County Station - Integrated Inspection Report 05000373/2023004 and 05000374/2023004
IR 05000373/20230122024-01-18018 January 2024
County Station - Biennial Problem Identification and Resolution Inspection Report 05000373/2023012 and 05000374/2023012
ML23354A2902024-01-0505 January 2024
Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0028 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting))
ML23360A6082023-12-27027 December 2023
County Station Request for Information for NRC Commercial Grade Dedication Inspection: Inspection Report 05000373/2024010 and 05000374/2024010
ML23278A1292023-12-14014 December 2023
Units 1 & 2; Limerick, Units 1 & 2; Nine Mile Point, Units 1 & 2; and Peach Bottom, Units 2 & 3 -Revision to Approved Alternatives to Use Boiling Water Reactor Vessel and Internals Project Guidelines
ML23305A1402023-12-13013 December 2023
Units 1 & 2; Nine Mile Point, Unit 2; Peach Bottom, Units 2 & 3; and Quad Cities, Units 1 and 2 - Issuance of Amendments to Adopt Traveler TSTF-580
ML23317A1192023-11-10010 November 2023
Constellation Energy Generation, LLC - 2023 Annual Report - Guarantees of Payment of Deferred Premiums
RS-23-120, Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information2023-11-10010 November 2023
Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information
IR 05000373/20230032023-11-0909 November 2023
County Station Integrated Inspection Report 05000373/2023003, 05000374/2023003, and 07200070/2023001
ML23286A2602023-11-0808 November 2023
Issuance of Amendment Nos. 260 and 245 to Renewed Facility Operating Licenses Relocation of Pressure and Temperature Limit Curves to the Pressure Temperature Report
IR 05000373/20234012023-11-0707 November 2023
County Station Security Baseline Inspection Report 05000373/2023401 and 05000374/2023401
RS-23-103, Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation2023-10-13013 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
2024-09-06
[Table view]
Category:Request for Additional Information (RAI)
MONTHYEARML24197A0162024-07-12012 July 2024
NRR E-mail Capture - Final RAI - Constellation Energy Generation, LLC - Fleet Request - License Amendment Request to Adopt TSTF-591
ML24142A3352024-05-21021 May 2024
Quad Cities—Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes
ML23360A6082023-12-27027 December 2023
County Station Request for Information for NRC Commercial Grade Dedication Inspection: Inspection Report 05000373/2024010 and 05000374/2024010
ML23264A7992023-09-21021 September 2023
NRR E-mail Capture - Final RAI - Constellation Energy Generation, LLC Fleet Request License Amendment Request to Adopt TSTF-580, Revision 1
ML23208A3182023-07-27027 July 2023
Notification of an NRC Biennial Licensed Operator Requalification Program Inspection and RFI
ML23153A1562023-06-0202 June 2023
NRR E-mail Capture - RAI LaSalle pressure-temperature Limits Report (PTLR) Amendment Request
ML23150A2482023-05-25025 May 2023
NRR E-mail Capture - RAI Re LaSalle Downcomer Analysis Amendment Request
ML23110A3202023-04-21021 April 2023
Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes Inspection
ML22361A0792022-12-27027 December 2022
Notification of NRC Baseline Inspection and Request for Information (05000374/2023001)
ML22256A0112022-09-12012 September 2022
NRR E-mail Capture - Request for Additional Information LaSalle County Station, Units 1 and 2 and Quad Cities Nuclear Power Station, Units 1 and 2 License Amendments Related to Fuel Storage
ML22138A4112022-05-18018 May 2022
NRR E-mail Capture - Lasalle 1 and 2 - (RAI) License Amendment Request Regarding New Fuel Storage Vault and Spent Fuel Storage Pool Criticality Methodologies, with Changes to TS Sections 4.3.1 and 5.6.5 (EPID-L-2021-LLA-0124)
ML22126A0392022-05-0606 May 2022
NRR E-mail Capture - Lasalle 1 and 2 Draft (RAI) License Amendment Request Regarding New Fuel Storage Vault and Spent Fuel Storage Pool Criticality Methodologies, with Proposed Changes to TS Sections 4.3.1 and 5.6.5
ML22097A0832022-04-0707 April 2022
County Station Information Request for the Cyber-Security Baseline Inspection, Notification to Perform Inspection 05000373/2022403 and 05000374/2022403
ML22062B0232022-03-0303 March 2022
NRR E-mail Capture - EPID-L-2022-LLR-0028, LaSalle Unit 1, Request for Additional Information (Rai), LaSalle Unit 1, Relief Request I4R-13 Relief from Code Examinations for 1B33-F060A and 1B33-F060B Repairs
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
ML22020A0642022-01-13013 January 2022
NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding Proposed Fleet Alternative for Repair of Water Level Instrumentation Partial Penetration Nozzles
ML21292A1782021-10-19019 October 2021
Information Request for a NRC Post-Approval Site Inspection for License Renewal 05000373/2022010
ML21256A1902021-09-10010 September 2021
NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding License Transfer Application
ML21207A0072021-07-26026 July 2021
NRR E-mail Capture - La Salle Units 1 and 2 - Request for Additional Information (RAI) License Amendment Request to Incorporate Licensing Topical Report NEDE-33885P-A, Revision 1, GNF CRDA Application Methodology(EPID-L-2021-LLA-0016)
ML21190A0192021-07-0808 July 2021
NRR E-mail Capture - Exelon Fleet - Request for Additional Information Regarding Adoption of TSTF-582 and TSTF-583-T
ML21187A2972021-07-0707 July 2021
Information Request for an NRC Triennial 10 CFR 50.59 (Evaluation of Changes, Tests, and Experiments) Baseline Inspection
ML21144A2132021-05-24024 May 2021
NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding License Transfer Application
ML21117A0342021-05-0505 May 2021
Request for Additional Information Regarding Proposed Alternative to Use ASME Code Case N-893
ML21119A2282021-04-29029 April 2021
NRR E-mail Capture - Request for Additional Information (RAI) - LaSalle, EPID-L-2020-LLA-0018, License Amendment Request (LAR) TSTF-505
ML21077A1902021-03-18018 March 2021
NRR E-mail Capture - Lasalle Units 1 and 2 - Request for Additional Information (RAI) Request for License Amendment Regarding Ultimate Heat Sink, (EPID-L-2020-LLA-0165)
ML21068A2762021-03-0909 March 2021
NRR E-mail Capture - La Salle Units 1 and 2 - Request for Additional Information (RAI) Relief Request I4R-12 Relief from Code Surface Examinations for 2B33-F060B Valve Repair (EPID-L-2020-LLA-0016)
ML21067A6752021-03-0808 March 2021
NRR E-mail Capture - La Salle Units 1 and 2 - Request for Additional Information (RAI) UHS Amendment Request (EPID-L-2020-LLA-0165)
ML21060B4352021-03-0101 March 2021
NRR E-mail Capture - Second Round - Request for Additional Information (Rais) EPID-L-2020-LLA-0018, LaSalle License Amendment Request to Adopt Risk Informed Completion Times TSTF-505, Revision 2
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
ML21053A0252021-02-20020 February 2021
NRR E-mail Capture - Request for Additional Information (Rais) - LaSalle Request for Exemption from Pre-Access Drug and Alcohol Testing
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)
ML21048A0432021-02-16016 February 2021
County Station - Notification of NRC Design Bases Assurance Inspection (Programs) and Initial Request for Information - Inspection Report 05000373/2021011 and 05000374/2021011
ML20364A2452020-12-29029 December 2020
Notification of an NRC Triennial Heat Sink Performance Inspection and Request for Information; Inspection Report 05000373/2021002; 05000374/2021002
ML20346A1042020-12-11011 December 2020
NRR E-mail Capture - LaSalle County Station, Units 1 and 2 - Request for Additional Information Regarding the License Amendment Request to Adopt 10 CFR 50.69
ML20330A1892020-11-25025 November 2020
Request for Information for an NRC Post-Approval Site Inspection for License Renewal; Inspection Report 05000374/2021010
ML20321A0852020-11-16016 November 2020
Notification of NRC Baseline Inspection and Request for Information (05000374/2021001)
ML20247J4082020-09-29029 September 2020
Apla Request for Additional Information LAR 50.69 and TSTF-505 (Epids L-2020-LLA-0017) and
ML20253A3422020-09-17017 September 2020
Correction to Request for Additional Information Request to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors (EPID-2020-LLA-0017)
ML20253A2272020-09-16016 September 2020
Correction to Request for Additional Information Application to Adopt Risk-Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b
ML20240A2182020-09-0303 September 2020
Request for Additional Information Regarding Amendment Request for Amendments to Renewed Facility Operating Licenses to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Co
ML20239A7262020-08-27027 August 2020
Supplemental Information Needed for Acceptance of Requested Licensing Action Regarding Request for a License Amendment to Technical Specification 3.7.3, Ultimate Heat Sink
ML20239A7982020-08-25025 August 2020
NRR E-mail Capture - Exelon Generation Company, LLC - Fleet License Amendment Request to Adopt TSTF-568, Revision 2
ML19275H1362019-10-0202 October 2019
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Three Mile Point 1 - Supplemental Information Needed to Proposed Alternative to Use ASME Code Case N-879
ML19120A2302019-04-29029 April 2019
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ML19087A2682019-03-28028 March 2019
NRR E-mail Capture - Request for Additional Information (RAI) - LaSalle 1 and 2, EPID-L-2018-LLA-0162, LAR Removal of Operating Mode Restrictions for Performing Surveillance Testing of the Div 3 Battery and HPCS DG
ML19065A0902019-03-0505 March 2019
NRR E-mail Capture - LaSalle 1 and 2, EPID-L-2018-LLR-0162, LAR Removal of Operating Mode Restrictions for Performing Surveillance Testing of the Div 3 Battery and HPCS DG, Additional Draft Request for Additional Information (RAI)
ML19058A2392019-02-27027 February 2019
Information Request to Support Upcoming Problem Identification and Resolution Inspection at LaSalle County Station, Units 1 and 2
ML19036A6562019-02-0505 February 2019
NRR E-mail Capture - LaSalle 1 and 2, EPID-L-2018-LLR-0123, Relief Request I3R-15, Third Inservice Inspection Interval, Request for Additional Information (RAI)
ML19050A0042019-01-22022 January 2019
NRR E-mail Capture - LaSalle 1 and 2, EPID-L-2018-LLR-0162, LAR Removal of Operating Mode Restrictions for Performing Surveillance Testing of the Div 3 Battery and HPCS DG, Draft Request for Additional Information (RAI)
2024-07-12
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 August 18, 2015 Mr. Michael P. Gallagher Vice President, License Renewal Projects Exelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348
SUBJECT:
REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346)
Dear Mr. Gallagher:
By letter dated December 9, 2014, Exelon Generation Company, LLC (Exelon) submitted an application pursuant to Title 10 of the Code of Federal Regulations Part 54, to renew the operating licenses NPF-11 and NPF-18 for LaSalle County Station (LSCS), Units 1 and 2, respectively. The staff of the U.S. Nuclear Regulatory Commission (NRC or the staff) is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review.
These requests for additional information were discussed with Mr. John Hufnagel, and a mutually agreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3019 or by e-mail at Jeffrey.Mitchell2@nrc.gov.
Sincerely,
/RA/
Jeffrey S. Mitchell, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374
Enclosure:
As stated cc: Listserv
August 18, 2015 Mr. Michael P. Gallagher Vice President, License Renewal Projects Exelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348
SUBJECT:
REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346)
Dear Mr. Gallagher:
By letter dated December 9, 2014, Exelon Generation Company, LLC (Exelon) submitted an application pursuant to Title 10 of the Code of Federal Regulations Part 54, to renew the operating licenses NPF-11 and NPF-18 for LaSalle County Station (LSCS), Units 1 and 2, respectively. The staff of the U.S. Nuclear Regulatory Commission (NRC or the staff) is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review.
These requests for additional information were discussed with Mr. John Hufnagel, and a mutually agreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3019 or by e-mail at Jeffrey.Mitchell2@nrc.gov.
Sincerely,
/RA/
Jeffrey S. Mitchell, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374
Enclosure:
As stated cc: Listserv DISTRIBUTION:
See next page ADAMS Accession Number: ML15204A630 *Concurred via e-mail OFFICE LA:DLR* PM:RPB1:DLR PM:RPB1:DLR BC:RPB1:DLR PM:RPB1:DLR NAME YEdmonds JMitchell RPlasse YDiaz-Sanabria JMitchell DATE 7/ 29 /15 7/ 31 /15 8/ 4 /15 8/ 18 /15 8/ 18 /15 OFFICIAL RECORD COPY
Letter to Michael P. Gallagher from Jeffrey S. Mitchell dated August 18, 2015
SUBJECT:
REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION - SET 9 (TAC NOS. MF5347 AND MF5346)
DISTRIBUTION:
E-MAIL:
PUBLIC RidsNrrDlr Resource RidsNrrDlrRpb1 Resource RidsNrrDlrRpb2 Resource RidsNrrDlrRerb Resource RidsNrrDlrRarb Resource RidsNrrDlrRasb Resource RidsNrrDlrRsrg Resource RidsNrrPMLaSalle Resource
J. Mitchell R. Plasse D. Drucker J. Danna J. Wachutka, OGC D. McIntyre, OPA M. Kunowski, RIII V. Mitlyng, RIII P. Chandrathil, RIII H. Logaras, RIII C. Lipa, RIII S. Sheldon, RIII R. Ruiz, RIII J. Robbins, RIII
LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION REQUESTS FOR ADDITIONAL INFORMATION - SET 9 (TAC NOS. MF5347 AND MF5346)
RAI B.2.1.7-3a
Background:
By letter dated June 25, 2015, the applicant responded to request for additional information (RAI) B.2.1.7-3 that addressed limited examination coverage for Generic Letter (GL) 88-01 welds. In its response, the applicant assessed a time period (February 2008 through March 2015) to evaluate the limited examination coverage of the welds within the scope of the BWR Stress Corrosion Cracking program. The applicant indicated that during the assessed period (February 2008 through March 2015) none of the Unit 1 Category A welds and Unit 2 Category C welds were inspected.
The applicant also indicated that there are only two Category D welds at Unit 2. The applicant further indicated that the examination coverage for each of the welds was limited to 50 percent because each weld is between pipe and a cast valve body where the current approved Performance Demonstration Initiative (PDI) method does not provide qualified and reliable results for the side of the weld adjacent to the cast valve body due to the specific contour of the valve body.
Issue:
As described in the background section, the response did not provide information regarding the examination coverage of Unit 1 Category A welds and Unit 2 Category C welds. The staff needs information on examination coverage of these welds based on previous inspection results in order to resolve the concern related to limited examination coverage.
The staff also needs additional information to evaluate the applicants justification for the limited examination coverage of the Unit 2 Category D welds. It is unclear whether the cast valve bodies associated with the Unit 2 Category D welds are made of cast materials resistant to intergranular stress corrosion cracking (IGSCC). In addition, the staff needs to confirm whether inspection results for the cast valve bodies indicate occurrence of IGSCC.
Request:
- 1. Provide information on the average examination coverage of Unit 1 Category A welds and Unit 2 Category C welds to characterize the overall degree of limited examination coverage. If limited examination coverage is identified for these welds, provide justification for why additional inspections are not necessary to compensate for the limited examination coverage of these welds.
ENCLOSURE
- 2. Provide the following information regarding the cast valve bodies associated with the two Category D welds at Unit 2:
a) Cast material grade (e.g., CF3M), carbon content, and ferrite content (including the method for determining ferrite content) of the cast valve bodies to clarify whether the materials are resistant to IGSCC in accordance with the staff positions in GL 88-01 b) American Society of Mechanical Engineers (ASME) Code Class and, if available, examination results of the cast valve bodies such as internal visual or surface examination results per ASME Code Section XI requirements RAI 4.2.1-1
Background:
License Renewal Application (LRA) Section 4.2.1 describes the applicants time-limited aging analysis (TLAA) on reactor vessel fluence calculations. LRA Section 4.2.1 also indicates that the 54-effective full power year (EFPY) fluence projections for 60 years of operation were calculated by using the NRC-approved Radiation Analysis Modeling Application (RAMA) methodology. The LRA further states that the 54-EFPY fluence projections compile the cumulative fluence resulting from each past operating cycle and add the predicted fluence estimate for future operating cycles through the period of extended operation. As discussed below, the NRC staff noted that these 54-EFPY fluence projections are independent from the fluence projections used in the current P-T limits.
LRA Section 4.2.1 states that the neutron fluence projections used as inputs to the current 40-year neutron embrittlement analyses for LSCS, Units 1 and 2 were developed in accordance with GE Licensing Topical Report NEDO-32983, General Electric Methodology for Reactor Pressure Vessel Fast Neutron Flux Evaluations, (ADAMS Accession No. ML072480121). LRA Section 4.2.1 also indicated that this GE methodology is in compliance with NRC Regulatory Guide 1.190, as approved by the NRC staff in the safety evaluation dated September 14, 2001.
Under LRA Section 4.2.1, the TLAA evaluation states that the 60-year RAMA neutron fluence projections compile the cumulative neutron fluence resulting from each past operating cycle and add the predicted neutron fluence estimated for future operating cycles through the period of extended operation. The RAMA neutron fluence projections are prepared using the BWRVIP-126 methodology. These 60-year neutron fluence projections are independent from the neutron fluence projections used with the current P-T curve submittals.
In comparison, the following reference indicates that the current 40-year (32-EFPY) P-T limits for LSCS Unit 1 use neutron fluence values that are calculated via the RAMA fluence methodology.
- NRC Safety Evaluation, LaSalle County Station, Unit 1, Issuance of Amendment Revising Pressure and Temperature Limits (TAC No. MF3270), dated November 25, 2014 (ADAMS Accession No. ML14220A517).
Section 3.1, Neutron Fluence Calculation, of the above reference states that the safety evaluation shall not be constructed as endorsement, agreement with, or approval of, the position regarding the combined use of neutron fluence methods to determine a total neutron fluence.
Issue:
The LRA does not address the RAMA methodology that the NRC staff evaluated in the safety evaluation regarding the current P-T limits for LSCS, Unit 1. Therefore, the NRC staff needs additional clarification as to the specific neutron fluence methodology that is used in the license renewal TLAAs. It is also unclear to the NRC staff how the applicant evaluates potential effects of updated neutron fluence calculation on existing neutron embrittlement analysis.
Request:
- 1. Clarify whether the 54-EFPY neutron fluences described in the LRA are based on the GE methodology, the RAMA methodology, or the combination of the two methodologies.
- 2. Clarify how the applicant will ensure that the actual fluence levels are bounded by the fluence levels analyzed in LRA Section 4.2.1.
RAI 4.2.8-1
Background:
LRA Section 4.2.8 describes the TLAA for the loss of preload of the reactor pressure vessel (RPV) core plate rim hold-down bolts resulting from irradiation effects. The LRA states that a fluence evaluation based on 54 EFPY has identified the bolts with the highest fluence values after 60 years of operation for Unit 1 (3.60x1019 n/cm2) and Unit 2 (3.85x1019 n/cm2). The LRA also states that an average fluence value of 8.0x1019 n/cm2 was evaluated for 40 years of operation which resulted in a maximum relaxation of 19 percent in preload for the RPV core plate rim hold-down bolts. The TLAA is dispositioned in accordance with 10 CFR 54.21(c)(1)(i) to remain valid through the period of extended operation.
The loss of preload analysis was performed as part of Boiling Water Reactor Vessel and Internals Project Technical Report 25 (BWRVIP-25), BWR Core Plate Inspection and Flaw Evaluation Guidelines. Section 2.1.3 of BWRVIP-25 states that it has been determined that a 5 percent to 19 percent reduction in preload is expected over a 40-year operating experience and that the bolts will maintain some amount of preload throughout the life of the plant. Section B.4 of Appendix B states that the loss of preload was recalculated based on 60 years of plant operation and that the reduction in preload remains 5 percent to 19 percent.
Issue:
The staff is unable to determine if the amount of relaxation experienced after 60 years of operation is bounded by the 40-year analyses because the fluence values used to determine the range in percent reduction of preload are not provided in BWRVIP-25 or the appendixes of the report.
Request:
Provide the analysis used to determine that an average fluence value of 8.0x1019 n/cm2 produces a maximum relaxation of 19 percent in preload for the RPV core plate rim hold-down bolts. Justify that the analysis adequately considers plant-specific configurations of reactor vessel internals and is bounded by the relaxation evaluations in BWRVIP-25.
RAI 4.2.10-1
Background:
Section 4.7.3.1.3 of the SRP-LR (NUREG-1800, Rev. 2) provides the NRCs review procedures for plant-specific TLAAs which will be managed in accordance with 10 CFR 54.21(c)(1)(iii).
SRP-LR Section 4.7.3.1.3 states that the staff is to review the aging management program proposed by the applicant to verify the program is adequate to manage the aging effects associated with the TLAA.
LRA Section 4.2.10 describes the TLAA evaluation for the loss of preload of the jet pump slip joint repair clamp. LRA Section 4.2.10 dispositions the TLAA in accordance with 10 CFR 54.21(c)(1)(iii) to be managed by Commitment No. 47 in LRA Section A.5. This commitment states that:
Prior to exceeding the limiting fluence value of 1.17x1020 n/cm2 at the Unit 1 jet pump slip joint clamp location, estimated to be at 50.7 EFPY, revise the analysis for the slip joint clamps for a higher acceptable fluence value or take other corrective action such as repair or replacement of the clamps to ensure acceptable clamp preload.
The implementation schedule for Commitment No. 47 is Prior to the period of extended operation.
Issue:
The LRA does not clearly identify how the applicant will ensure that the limiting fluence value is not exceeded. The staff is unable to determine if the applicants program or activities are adequate to ensure that the limiting fluence value is not exceeded.
Request:
Identify the program or a set of activities that will be used for the jet pump slip joint repair clamp to ensure that the limiting fluence value is not exceeded. Justify that the program or activities are adequate for managing the aging effect of loss of preload of the jet pump slip joint repair clamp.
