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| ==SUBJECT:== | | ==SUBJECT:== |
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| THREE MILE ISLAND NUCLEAR STATION, UNIT 1 -CLOSURE EVALUATION FOR REPORT PURSUANT TO 10 CFR 50.46 REQUIREMENTS RELATED TO THERMAL CONDUCTIVITY DEGRADATION (CAC NO. MF5564) | | THREE MILE ISLAND NUCLEAR STATION, UNIT 1 -CLOSURE EVALUATION FOR REPORT PURSUANT TO 10 CFR 50.46 REQUIREMENTS RELATED TO THERMAL CONDUCTIVITY DEGRADATION (CAC NO. MF5564) |
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| ==Dear Mr. Hanson:== | | ==Dear Mr. Hanson:== |
| By letter dated December 22, 2014, as supplemented by letter dated April 6, 2015 (Agencywide Documents Access and Management System Accession Nos. ML 14356A342 and ML 15097A125, respectively), Exelon Generation Company, LLC submitted a report pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3) for the Three Mile Island Nuclear Station, Unit 1 (TMl-1 ). This report described a significant error identified in the emergency core cooling system evaluation model and an estimate of the effect of the error on the predicted peak cladding temperature for TMl-1. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of this report. Based on this evaluation, the NRC staff has determined that the report, as supplemented, satisfies the reporting requirements of 10 CFR 50.46(a)(3) for TMl-1. A copy of the staff's closure evaluation is enclosed. This completes the NRC staff's efforts associated with Cost Activity Code No. MF5564. Should you have any questions, please contact me at (301) 415-1022 or Robert.Gladney@nrc.gov. Docket No. 50-289 | | By letter dated December 22, 2014, as supplemented by letter dated April 6, 2015 (Agencywide Documents Access and Management System Accession Nos. ML 14356A342 and ML 15097A125, respectively), |
| | Exelon Generation |
| | : Company, LLC submitted a report pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3) for the Three Mile Island Nuclear Station, Unit 1 (TMl-1 ). This report described a significant error identified in the emergency core cooling system evaluation model and an estimate of the effect of the error on the predicted peak cladding temperature for TMl-1. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of this report. Based on this evaluation, the NRC staff has determined that the report, as supplemented, satisfies the reporting requirements of 10 CFR 50.46(a)(3) for TMl-1. A copy of the staff's closure evaluation is enclosed. |
| | This completes the NRC staff's efforts associated with Cost Activity Code No. MF5564. Should you have any questions, please contact me at (301) 415-1022 or Robert.Gladney@nrc.gov. |
| | Docket No. 50-289 |
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| ==Enclosure:== | | ==Enclosure:== |
| Staff's Closure Evaluation cc w/enclosure: Distribution via Listserv Sincerely, Robert L. Gladney, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 CLOSURE EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION STAFF RELATED TO REPORT PURSUANT TO 10 CFR 50.46 EXELON GENERATION COMPANY. LLC THREE MILE ISLAND NUCLEAR STATION. UNIT 1 DOCKET NO. 50-289 | | |
| | Staff's Closure Evaluation cc w/enclosure: |
| | Distribution via Listserv Sincerely, Robert L. Gladney, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 CLOSURE EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION STAFF RELATED TO REPORT PURSUANT TO 10 CFR 50.46 EXELON GENERATION COMPANY. |
| | LLC THREE MILE ISLAND NUCLEAR STATION. |
| | UNIT 1 DOCKET NO. 50-289 |
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| ==1.0 INTRODUCTION== | | ==1.0 INTRODUCTION== |
| By letter dated December 22, 2014, as supplemented by letter dated April 6, 2015 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML 14356A342 and ML 15097A125, respectively), Exelon Generation Company, LLC (Exelon, the licensee) submitted a report pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3) for the Three Mile Island Nuclear Station, Unit 1 (TMl-1 ). This report described a significant error identified in the emergency core cooling system (ECCS) evaluation model (EM) and an estimate of the effect of the error on the predicted peak cladding temperature (PCT) for TMl-1. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of the report and determined, as discussed below, that the report, as supplemented, satisfies the reporting requirements of 10 CFR 50.46(a)(3) for TMl-1.
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| ==2.0 REGULATORY EVALUATION==
| | By letter dated December 22, 2014, as supplemented by letter dated April 6, 2015 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML 14356A342 and ML 15097A125, respectively), |
| 2.1 Regulatory Requirements Specific requirements with regard to ECCS for light-water nuclear power reactors are found in 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors." Within this regulation, 10 CFR 50.46(a)(1 )(i) requires, in part, that, "ECCS cooling performance must be calculated in accordance with an acceptable evaluation model." Paragraph (a)(3)(i) of 10 CFR 50.46 requires licensees to "estimate the effect of any change to or error in an acceptable evaluation model, or in the application of such a model, to determine if the change or error is significant." For the purposes of 10 CFR 50.46, a significant change or error is one that results in a calculated PCT difference of more than 50 degrees Fahrenheit (°F) "from the temperature calculated for the limiting transient using the last acceptable model, or is [an accumulation] of changes and errors such that the sum of the absolute magnitudes of the respective temperature changes is greater than 50 °F." For each change to or error discovered in an acceptable EM, or in the application of such a model, 10 CFR 50.46(a)(3)(ii) requires the affected licensee to report the nature of the change Enclosure or error and its estimated effect on the limiting ECCS analysis to the NRC at least annually. If the change or error is significant, the licensee is required to provide this report within 30 days. The report is to include "a proposed for providing a reanalysis or taking other action as may be needed to show compliance with [10 CFR] 50.46 requirements." Paragraph (b) of 1 O CFR 50.46 provides the acceptance criteria for ECCS performance. In particular, 10 CFR 50.46(b)(1 ), "Peak cladding temperature," states, "The calculated maximum fuel element cladding temperature shall not exceed 2200° F." 2.2 Background The NRG-approved AREVA Inc. (AREVA) proprietary topical report BAW-10192P-A, "BWNT Loss-of-Coolant Accident Evaluation Model for Once-Through Steam Generator Plants" (hereinafter "BWNT LOCA EM"), 1 is the acceptable EM used to evaluate ECCS performance at TMl-1. In accordance with 10 CFR Part 21, "Reporting of Defects and Noncompliance," AREVA reported an error in its loss-of-coolant accident (LOCA) analysis for plants with a Babcock & Wilcox design, including TMl-1, by a letter to the NRC dated December 16, 2014 (ADAMS Accession No. ML 14351A308). In its report, AREVA stated that the current fuel "thermal conductivity model does not adequately represent the change in conductivity with burnup for the fuel." This defect relates to the uranium fuel thermal conductivity models in the fuel thermal-mechanical codes TAC032 and GDTAC0,3 which are part of the BWNT LOCA EM. The defect resulted in an under-prediction of the large-break PCT at TMl-1. To compensate for the under-prediction of PCT, AREVA stated that each affected plant, including TMl-1, was advised to reduce fuel linear heat rate (LHR) by 2 kilowatts per foot (kW/ft). Based on AREVA's notification, Exelon submitted its December 22, 2014, letter to notify the NRC that the defect constituted an error in the ECCS EM for TMl-1. The licensee's letter provided (1) a description of the nature of the error and its estimated effect on the PCT; (2) a summary of actions taken to ensure compliance with 10 CFR 50.46 requirements, including implementing the 2 kW/ft LHR reduction; and (3) a commitment that a large break LOCA (LBLOCA) reanalysis, accounting for the effects of thermal conductivity degradation (TCD), would be performed for TMl-1 by March 31, 2017. (This commitment was superseded by the commitment submitted in the April 6, 2015, letter, which is described in Section 3.2 of this evaluation.) The December 22, 2014, letter stated that the TCD-related defect was estimated to cause the PCT at TMl-1 to increase 393 °F. The licensee's implementation of a 2 kW/ft LHR reduction was estimated to offset the TCD effect by reducing the PCT by 375 °F. Therefore, the predicted 1 BAW-10192P-A describes the ECCS EM; however, the EM requires use of input from approved thermal-mechanical models. Plant-specific application is described in further detail in BAW-10179P-A, "Safety Criteria and Methodology for Acceptable Cycle Reload Analyses." 2 AREVA NP Licensing Topical Report BAW-10162P-A, "TAC03 -Fuel Pin Thermal Analysis Code." 3 AREVA NP Licensing Topical Report BAW-10184P-A, "GDTACO -Urania Gadolinia Fuel Pin Thermal Analysis Code." PCT for TMl-1 increases from 1,890 °F to 1,908 °F, which remains less than the regulatory limit of 2200 °F. 2.3 Regulatory Commitment The licensee provided the following commitment in its December 22, 2014, letter. Exelon will perform a full LBLOCA reanalysis for TMI Unit 1 by March 31, 2017. The effects of fuel pellet thermal conductivity degradation will be accounted for by use of a fuel temperature uncertainty adjustment factor based on COPERNIC2. However, in its April 6, 2015, letter, the licensee provided the following new commitment, which supersedes its December 22, 2014, commitment: The full LBLOCA reanalysis will be completed within 21 months following NRC issuance of the final Safety Evaluation Report (SER) for BAW-10179 Revision 9, which incorporates by reference the supplement to BAW-10192P-A Revision 0. Therefore, in its April 6, 2015, letter, the licensee committed to completing this reanalysis within 21 months following NRC issuance of a final SER, approving BAW-10179, Revision 9, for use. The NRC staff determined that this commitment revision is acceptable as it does not affect the outcome of the NRC staff's review or the licensee's compliance with the regulations.
| | Exelon Generation |
| | : Company, LLC (Exelon, the licensee) submitted a report pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3) for the Three Mile Island Nuclear Station, Unit 1 (TMl-1 ). This report described a significant error identified in the emergency core cooling system (ECCS) evaluation model (EM) and an estimate of the effect of the error on the predicted peak cladding temperature (PCT) for TMl-1. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of the report and determined, as discussed below, that the report, as supplemented, satisfies the reporting requirements of 10 CFR 50.46(a)(3) for TMl-1. 2.0 REGULATORY EVALUATION 2.1 Regulatory Requirements Specific requirements with regard to ECCS for light-water nuclear power reactors are found in 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors." |
| | Within this regulation, 10 CFR 50.46(a)(1 |
| | )(i) requires, in part, that, "ECCS cooling performance must be calculated in accordance with an acceptable evaluation model." Paragraph (a)(3)(i) of 10 CFR 50.46 requires licensees to "estimate the effect of any change to or error in an acceptable evaluation model, or in the application of such a model, to determine if the change or error is significant." |
| | For the purposes of 10 CFR 50.46, a significant change or error is one that results in a calculated PCT difference of more than 50 degrees Fahrenheit |
| | (°F) "from the temperature calculated for the limiting transient using the last acceptable model, or is [an accumulation] |
| | of changes and errors such that the sum of the absolute magnitudes of the respective temperature changes is greater than 50 °F." For each change to or error discovered in an acceptable EM, or in the application of such a model, 10 CFR 50.46(a)(3)(ii) requires the affected licensee to report the nature of the change Enclosure or error and its estimated effect on the limiting ECCS analysis to the NRC at least annually. |
| | If the change or error is significant, the licensee is required to provide this report within 30 days. The report is to include "a proposed for providing a reanalysis or taking other action as may be needed to show compliance with [10 CFR] 50.46 requirements." |
| | Paragraph (b) of 1 O CFR 50.46 provides the acceptance criteria for ECCS performance. |
| | In particular, 10 CFR 50.46(b)(1 |
| | ), "Peak cladding temperature," |
| | states, "The calculated maximum fuel element cladding temperature shall not exceed 2200° F." 2.2 Background The NRG-approved AREVA Inc. (AREVA) proprietary topical report BAW-10192P-A, "BWNT Loss-of-Coolant Accident Evaluation Model for Once-Through Steam Generator Plants" (hereinafter "BWNT LOCA EM"), 1 is the acceptable EM used to evaluate ECCS performance at TMl-1. In accordance with 10 CFR Part 21, "Reporting of Defects and Noncompliance," |
| | AREVA reported an error in its loss-of-coolant accident (LOCA) analysis for plants with a Babcock & Wilcox design, including TMl-1, by a letter to the NRC dated December 16, 2014 (ADAMS Accession No. ML 14351A308). |
| | In its report, AREVA stated that the current fuel "thermal conductivity model does not adequately represent the change in conductivity with burnup for the fuel." This defect relates to the uranium fuel thermal conductivity models in the fuel thermal-mechanical codes TAC032 and GDTAC0,3 which are part of the BWNT LOCA EM. The defect resulted in an under-prediction of the large-break PCT at TMl-1. To compensate for the under-prediction of PCT, AREVA stated that each affected plant, including TMl-1, was advised to reduce fuel linear heat rate (LHR) by 2 kilowatts per foot (kW/ft). |
| | Based on AREVA's notification, Exelon submitted its December 22, 2014, letter to notify the NRC that the defect constituted an error in the ECCS EM for TMl-1. The licensee's letter provided (1) a description of the nature of the error and its estimated effect on the PCT; (2) a summary of actions taken to ensure compliance with 10 CFR 50.46 requirements, including implementing the 2 kW/ft LHR reduction; and (3) a commitment that a large break LOCA (LBLOCA) reanalysis, accounting for the effects of thermal conductivity degradation (TCD), would be performed for TMl-1 by March 31, 2017. (This commitment was superseded by the commitment submitted in the April 6, 2015, letter, which is described in Section 3.2 of this evaluation.) |
| | The December 22, 2014, letter stated that the TCD-related defect was estimated to cause the PCT at TMl-1 to increase 393 °F. The licensee's implementation of a 2 kW/ft LHR reduction was estimated to offset the TCD effect by reducing the PCT by 375 °F. Therefore, the predicted 1 BAW-10192P-A describes the ECCS EM; however, the EM requires use of input from approved thermal-mechanical models. Plant-specific application is described in further detail in BAW-10179P-A, "Safety Criteria and Methodology for Acceptable Cycle Reload Analyses." |
| | 2 AREVA NP Licensing Topical Report BAW-10162P-A, "TAC03 -Fuel Pin Thermal Analysis Code." 3 AREVA NP Licensing Topical Report BAW-10184P-A, "GDTACO -Urania Gadolinia Fuel Pin Thermal Analysis Code." PCT for TMl-1 increases from 1,890 °F to 1,908 °F, which remains less than the regulatory limit of 2200 °F. 2.3 Regulatory Commitment The licensee provided the following commitment in its December 22, 2014, letter. Exelon will perform a full LBLOCA reanalysis for TMI Unit 1 by March 31, 2017. The effects of fuel pellet thermal conductivity degradation will be accounted for by use of a fuel temperature uncertainty adjustment factor based on COPERNIC2. |
| | : However, in its April 6, 2015, letter, the licensee provided the following new commitment, which supersedes its December 22, 2014, commitment: |
| | The full LBLOCA reanalysis will be completed within 21 months following NRC issuance of the final Safety Evaluation Report (SER) for BAW-10179 Revision 9, which incorporates by reference the supplement to BAW-10192P-A Revision |
| | : 0. Therefore, in its April 6, 2015, letter, the licensee committed to completing this reanalysis within 21 months following NRC issuance of a final SER, approving BAW-10179, Revision 9, for use. The NRC staff determined that this commitment revision is acceptable as it does not affect the outcome of the NRC staff's review or the licensee's compliance with the regulations. |
| | 3.0 TECHNICAL EVALUATION 3.1 Use of an Acceptable Evaluation Model for Reanalysis The December 22, 2014, letter indicated that Exelon would complete a full LBLOCA reanalysis incorporating the effects of TCD by March 31, 2017. This commitment was superseded by a commitment in the April 6, 2015, letter that indicated that the reanalysis will be completed "within 21 months following NRC issuance of the final Safety Evaluation Report (SER) for BAW-10179, Revision 9, which incorporates by reference the supplement to BAW-10192P-A, Revision O." Section 4.3.2.3 of the BWNT LOCA EM requires licensees to use NRG-approved fuel thermal-mechanical models to be consistent with the topical report. The fuel temperature uncertainty values used in TAC03 and GDTACO are specified in the NRG-approved fuel performance methodology documented in BAW-10162P-A and BAW-10184P-A. |
| | The AREVA report identified that these uncertainty values need to be modified in order to account for TCD. In its April 6, 2015, letter, the licensee stated that AREVA will develop a supplement to its BWNT LOCA EM and submit it for NRC review and approval. |
| | 4 The licensee stated that the supplement will describe the modifications to the BWNT LOCA EM necessary for correction of the TCD issue. Based on this information, the NRC staff determined that the licensee has 4 By letter dated November 25, 2015 (ADAMS Accession No. ML 15337 A242), AREVA submitted Request for Review and Approval of BAW-10192PA-OO, Supplement 1, Revision 0, "BWNT LOCA BWNT Loss-of-Coolant Accident Evaluation Model for Once-Through Steam Generator Plants." adequately described how it will ensure that ECCS cooling performance is calculated using an acceptable EM. 3.2 Adequacy of Reanalysis Scope As discussed above, the licensee stated that the TCD-related model changes will be incorporated as a supplement to the BWNT LOCA EM. The December 22, 2014, letter states that, "the reanalysis will address the significant EM error corrections to cover [in addition to the TCD-related error correction] |
| | the ECCS bypass error correction and column weldment modeling changes." |
| | Based on the magnitude of the estimated effect of a TCD correction on the TMl-1 ECCS evaluation, in addition to these additional, significant model changes and error corrections, the NRC staff determined that these model revisions would significantly change the predicted ECCS performance for TMl-1. Regarding the evaluation of ECCS performance, 10 CFR 50.46(a)(1 |
| | )(i) states, in part, that ECCS cooling performance "must be calculated for a number of postulated loss-of-coolant accidents of different sizes, locations, and other properties sufficient to provide assurance that the most severe postulated loss-of-coolant accidents are calculated." |
| | In its April 6, 2015, letter, the licensee stated: The revised LBLOCA analyses will include a review of the current LBLOCA analyses to determine if the conclusion of the previous evaluation of a spectrum of break sizes, locations, and other properties is sufficient to verify the selection of the most severe hypothetical case. If the review determines that additional calculations are required to select the most severe hypothetical case, then the additional calculations will be performed. |
| | Based on NRC staff experience, various issues associated with an ECCS evaluation may be addressed using an evaluation of a spectrum of break sizes, locations, and other properties, and this evaluation may be performed on a more general, simplified basis. Once a set of generally limiting properties is identified, a more detailed, plant-specific analysis identifies the exact limiting properties and determines the results for comparison against the 1 O CFR 50.46(b) acceptance criteria. |
| | The licensee's statement above is consistent with this practice. |
| | Based on the discussion above, the staff determined that the licensee adequately described how it will provide assurance that the most severe postulated LOCAs are calculated. |
| | 3.3 Technical Specification (TS) Impacts The TMl-1 TS 6.9.5.2 requires, in part: The analytical methods used to determine the core operating limits addressed by the individual Technical Specifications shall be those previously reviewed and approved by the NRC for use at TMl-1, specifically: |
| | (1) BAW-10179 P-A, "Safety [Criteria] |
| | 5 and Methodology for Acceptable Cycle Reload Analyses." |
| | The current revision level shall be specified in the COLR. 5 Note that the word, "criteria," |
| | appears to be omitted from the TS core operating limit report reference. The BWNT LOCA EM is incorporated into BAW-10179P-A by reference. |
| | In a letter dated March 8, 2015 (ADAMS Accession No. ML 15020A737), |
| | the NRC staff noted that the application of TCD-corrected fuel temperature uncertainties to TAC03 and GDTACO may be inconsistent with Section 9.2.3, "Steady-State Fuel Data Input to LOCA EMs," of BAW-10179P-A. |
| | In its April 6, 2015, letter, the licensee stated that AREVA would also revise BAW-10179P-A to incorporate a reference to the BWNT LOCA EM supplement, and this revision would be submitted to the NRC for review and approval. |
| | The licensee stated that it will notify the NRC when the reanalysis is complete. |
| | Based on the discussion above, the NRC staff determined that the licensee has adequately described how it will comply with TS 6.9.5.2 with the application of the BWNT LOCA EM supplement. |
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| | ==4.0 CONCLUSION== |
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| | Based on its review, the NRC staff concluded that Exelon's report, as supplemented, satisfies the reporting requirements of 1 O CFR 50.46(a)(3). |
| | The report described the nature of the TCD-related error and provided its estimated effect on the PCT for the limiting ECCS evaluation. |
| | The report also indicated that the licensee took action to reduce LHR limits to compensate for the effect of TCD and showed that the predicted PCT would remain below 2200 °F. The report, as supplemented, included a proposed schedule for performing reanalysis and taking other actions, as needed, to comply with 10 CFR 50.46 requirements. |
| | Principal Contributors: |
| | B. Parks J. Whitman R. Gladney Date: December 17, 2015 December 17, 2015 Mr. Bryan C. Hanson President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555 |
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| ==3.0 TECHNICAL EVALUATION== | | ==SUBJECT:== |
| 3.1 Use of an Acceptable Evaluation Model for Reanalysis The December 22, 2014, letter indicated that Exelon would complete a full LBLOCA reanalysis incorporating the effects of TCD by March 31, 2017. This commitment was superseded by a commitment in the April 6, 2015, letter that indicated that the reanalysis will be completed "within 21 months following NRC issuance of the final Safety Evaluation Report (SER) for BAW-10179, Revision 9, which incorporates by reference the supplement to BAW-10192P-A, Revision O." Section 4.3.2.3 of the BWNT LOCA EM requires licensees to use NRG-approved fuel thermal-mechanical models to be consistent with the topical report. The fuel temperature uncertainty values used in TAC03 and GDTACO are specified in the NRG-approved fuel performance methodology documented in BAW-10162P-A and BAW-10184P-A. The AREVA report identified that these uncertainty values need to be modified in order to account for TCD. In its April 6, 2015, letter, the licensee stated that AREVA will develop a supplement to its BWNT LOCA EM and submit it for NRC review and approval.4 The licensee stated that the supplement will describe the modifications to the BWNT LOCA EM necessary for correction of the TCD issue. Based on this information, the NRC staff determined that the licensee has 4 By letter dated November 25, 2015 (ADAMS Accession No. ML 15337 A242), AREVA submitted Request for Review and Approval of BAW-10192PA-OO, Supplement 1, Revision 0, "BWNT LOCA BWNT Loss-of-Coolant Accident Evaluation Model for Once-Through Steam Generator Plants." adequately described how it will ensure that ECCS cooling performance is calculated using an acceptable EM. 3.2 Adequacy of Reanalysis Scope As discussed above, the licensee stated that the TCD-related model changes will be incorporated as a supplement to the BWNT LOCA EM. The December 22, 2014, letter states that, "the reanalysis will address the significant EM error corrections to cover [in addition to the TCD-related error correction] the ECCS bypass error correction and column weldment modeling changes." Based on the magnitude of the estimated effect of a TCD correction on the TMl-1 ECCS evaluation, in addition to these additional, significant model changes and error corrections, the NRC staff determined that these model revisions would significantly change the predicted ECCS performance for TMl-1. Regarding the evaluation of ECCS performance, 10 CFR 50.46(a)(1 )(i) states, in part, that ECCS cooling performance "must be calculated for a number of postulated loss-of-coolant accidents of different sizes, locations, and other properties sufficient to provide assurance that the most severe postulated loss-of-coolant accidents are calculated." In its April 6, 2015, letter, the licensee stated: The revised LBLOCA analyses will include a review of the current LBLOCA analyses to determine if the conclusion of the previous evaluation of a spectrum of break sizes, locations, and other properties is sufficient to verify the selection of the most severe hypothetical case. If the review determines that additional calculations are required to select the most severe hypothetical case, then the additional calculations will be performed. Based on NRC staff experience, various issues associated with an ECCS evaluation may be addressed using an evaluation of a spectrum of break sizes, locations, and other properties, and this evaluation may be performed on a more general, simplified basis. Once a set of generally limiting properties is identified, a more detailed, plant-specific analysis identifies the exact limiting properties and determines the results for comparison against the 1 O CFR 50.46(b) acceptance criteria. The licensee's statement above is consistent with this practice. Based on the discussion above, the staff determined that the licensee adequately described how it will provide assurance that the most severe postulated LOCAs are calculated. 3.3 Technical Specification (TS) Impacts The TMl-1 TS 6.9.5.2 requires, in part: The analytical methods used to determine the core operating limits addressed by the individual Technical Specifications shall be those previously reviewed and approved by the NRC for use at TMl-1, specifically: (1) BAW-10179 P-A, "Safety [Criteria]5 and Methodology for Acceptable Cycle Reload Analyses." The current revision level shall be specified in the COLR. 5 Note that the word, "criteria," appears to be omitted from the TS core operating limit report reference. The BWNT LOCA EM is incorporated into BAW-10179P-A by reference. In a letter dated March 8, 2015 (ADAMS Accession No. ML 15020A737), the NRC staff noted that the application of TCD-corrected fuel temperature uncertainties to TAC03 and GDTACO may be inconsistent with Section 9.2.3, "Steady-State Fuel Data Input to LOCA EMs," of BAW-10179P-A. In its April 6, 2015, letter, the licensee stated that AREVA would also revise BAW-10179P-A to incorporate a reference to the BWNT LOCA EM supplement, and this revision would be submitted to the NRC for review and approval. The licensee stated that it will notify the NRC when the reanalysis is complete. Based on the discussion above, the NRC staff determined that the licensee has adequately described how it will comply with TS 6.9.5.2 with the application of the BWNT LOCA EM supplement.
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| ==4.0 CONCLUSION== | | THREE MILE ISLAND NUCLEAR STATION, UNIT 1 -CLOSURE EVALUATION FOR REPORT PURSUANT TO 10 CFR 50.46 REQUIREMENTS RELATED TO THERMAL CONDUCTIVITY DEGRADATION (CAC NO. MF5564) |
| Based on its review, the NRC staff concluded that Exelon's report, as supplemented, satisfies the reporting requirements of 1 O CFR 50.46(a)(3). The report described the nature of the TCD-related error and provided its estimated effect on the PCT for the limiting ECCS evaluation. The report also indicated that the licensee took action to reduce LHR limits to compensate for the effect of TCD and showed that the predicted PCT would remain below 2200 °F. The report, as supplemented, included a proposed schedule for performing reanalysis and taking other actions, as needed, to comply with 10 CFR 50.46 requirements. Principal Contributors: B. Parks J. Whitman R. Gladney Date: December 17, 2015
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| | ==Dear Mr. Hanson:== |
| | By letter dated December 22, 2014, as supplemented by letter dated April 6, 2015 (Agencywide Documents Access and Management System Accession Nos. ML 14356A342 and ML 15097A125, respectively), |
| | Exelon Generation |
| | : Company, LLC submitted a report pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3) for the Three Mile Island Nuclear Station, Unit 1 (TMl-1). |
| | This report described a significant error identified in the emergency core cooling system evaluation model and an estimate of the effect of the error on the predicted peak cladding temperature for TMl-1. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of this report. Based on this evaluation, the NRC staff has determined that the report, as supplemented, satisfies the reporting requirements of 10 CFR 50.46(a)(3) for TMl-1. A copy of the staff's closure evaluation is enclosed. |
| | This completes the NRC staff's efforts associated with Cost Activity Code No. MF5564. Should you have any questions, please contact me at (301) 415-1022 or Robert.Gladney@nrc.gov. |
| | Docket No. 50-289 |
| | |
| | ==Enclosure:== |
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| ML 15306A503 OFFICE DORL/LPL 1-2/PM DORL/LPL 1-2/LA DSS/SNPB/BC DSS/SRXB/BC DORL/LPL 1-2/BC DORL/LPL 1-2/PM NAME RGladney LRonewicz JDean CJackson DBroaddus RGladney DATE 12/17/2015 11/27/2015 11/05/2015 11/12/2015 12/17/2015 12/17/2015}} | | Staff's Closure Evaluation cc w/enclosure: |
| | Distribution via Listserv DISTRIBUTION: |
| | PUBLIC LPL 1-2 R/F BParks, NRR Sincerely, IRA/ Robert L. Gladney, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation RidsRgn1 MailCenter Resource RidsACRS_MailCTR Resource RidsNrrDssSnpb Resource |
| | : JWhitman, NRR RidsNrrDssSrxb Resource RidsNrrPMThreeMilelsland Resource RidsNrrDorlLpl1-2 Resource RidsNrrLALRonewicz Resource ADAMS Accession No.: ML 15306A503 OFFICE DORL/LPL 1-2/PM DORL/LPL 1-2/LA DSS/SNPB/BC DSS/SRXB/BC DORL/LPL 1-2/BC DORL/LPL 1-2/PM NAME RGladney LRonewicz JDean CJackson DBroaddus RGladney DATE 12/17/2015 11/27/2015 11/05/2015 11/12/2015 12/17/2015 12/17/2015 OFFICIAL RECORD COPY}} |
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MONTHYEARML15306A5032015-12-17017 December 2015
Closure Evaluation for Report Pursuant to 10 CFR 50.46 Requirements Related to Thermal Conductivity Degradation
Project stage: Other
2015-12-17
[Table View] |
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Category:Letter
MONTHYEARRS-24-097, Notice of Intent to Pursue Subsequent License Renewal for Three Mile Island Nuclear Station, Unit 12024-10-23023 October 2024
Notice of Intent to Pursue Subsequent License Renewal for Three Mile Island Nuclear Station, Unit 1
ML24256A0422024-10-0404 October 2024
Updated Post-Shutdown Decommissioning Activities Report, Rev. 6
ML24240A1692024-09-18018 September 2024
Cy 2023 Summary of Decommissioning Trust Fund Status
ML24242A3032024-09-0909 September 2024
Letter - Three Mile Island Station, Unit 2, Issuance of Amendment No. 68, Historic and Cultural Resources
IR 05000320/20240012024-08-28028 August 2024
TMI-2 Solutions, LLC, Three Mile Island Nuclear Station, Unit 2 - NRC Inspection Report Nos. 05000320/2024001 and 05000320/2024002
ML24240A2222024-08-27027 August 2024
Response to Request for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 6
ML24220A2742024-08-15015 August 2024
Request for Additional Information Clarification Call Regarding Three Mile Island Station, Unit 2, Amended Post-Shutdown Decommissioning Activities Report, Rev. 6
ML24135A3292024-08-0909 August 2024
Amendment No 68, Historic and Cultural Resources Cover Letter
IR 07200077/20240012024-06-18018 June 2024
Constellation Energy Generation, LLC, Three Mile Island Nuclear Station, Unit 1 - NRC Inspection Report No. 07200077/2024001
ML24157A3672024-06-13013 June 2024
Updated Post-Shutdown Decommissioning Activities Report Request for Additional Information Transmittal Letter
ML24135A1972024-06-13013 June 2024
– Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0091 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting))
ML24151A6482024-06-0303 June 2024
Changes in Reactor Decommissioning Branch Project Management Assignments for Some Decommissioning Facilities
ML24120A3242024-05-24024 May 2024
TMI-2 Email to Fws
RS-24-055, 2023 Corporate Regulatory Commitment Change Summary Report2024-05-17017 May 2024
2023 Corporate Regulatory Commitment Change Summary Report
ML24121A2472024-04-29029 April 2024
And Three Mile Island, Unit 2 - 2023 Occupational Radiation Exposure Annual Report
ML24120A2552024-04-29029 April 2024
Annual Radiological Environmental Operating Report
ML24113A0212024-04-18018 April 2024
(TMI-2), Supplement to Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation
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
ML24092A0012024-03-28028 March 2024
(TMI-2), Decommissioning Trust Fund Annual Report
ML24088A0122024-03-28028 March 2024
Notification of Amended Post-Shutdown Decommissioning Activities Report (PSDAR) in Accordance with 10 CFR 50.82(a)(7), Revision 6
ML24065A0042024-03-28028 March 2024
Submittal of 2023 Aircraft Movement Data Annual Report
ML24085A2152024-03-25025 March 2024
(TMI-2) - Annual Notification of Property Insurance Coverage
RS-24-023, Report on Status of Decommissioning Funding.2024-03-22022 March 2024
Report on Status of Decommissioning Funding.
ML24052A0602024-03-20020 March 2024
– Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0061 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting))
ML24075A0062024-03-14014 March 2024
List of Threatened and Endangered Species That May Occur in Your Proposed Project Location or May Be Affected by Your Proposed Project
ML24074A3922024-03-14014 March 2024
Response to Request for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5
ML24073A2312024-03-13013 March 2024
And Three Mile Island Nuclear Station, Unit 2 - Management Change
ML24044A0092024-02-12012 February 2024
License Amendment Request – Three Mile Island, Unit 2, Historic and Cultural Resources Review, Response to Request for Additional Information
IR 05000320/20230042024-02-0707 February 2024
TMI-2 Solutions, LLC, Three Mile Island Nuclear Station, Unit 2 - NRC Inspection Report 05000320/2023004
ML24038A0222024-02-0505 February 2024
Achp Letter on Section 106 Programmatic Agreement Participation
IR 05000289/20230062024-01-29029 January 2024
Constellation Energy Generation, LLC, Three Mile Island Nuclear Station, Unit 1 - NRC Inspection Report No. 05000289/2023006
ML23342A1242024-01-0909 January 2024
Independent Spent Fuel Storage Installation Security Inspection Plan
ML23325A1092024-01-0505 January 2024
Review of the Management Plan for Three Mile Island Station, Unit No. 2, Debris Material
ML23354A2062023-12-20020 December 2023
(TMI-2), Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation
ML23354A2112023-12-20020 December 2023
Response to Request for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5
IR 05000320/20230032023-11-28028 November 2023
TMI-2 Solutions, LLC, Three Mile Island Nuclear Station, Unit 2, NRC Inspection Report No. 05000320/2023003
ML23243A9082023-08-29029 August 2023
Shpo Letter to TMI-2 Regarding Section 106 Activities
IR 05000320/20230022023-08-17017 August 2023
TMI-2 Solutions, LLC, Three Mile Island Nuclear Station, Unit 2 - NRC Inspection Report 05000320/2023002
ML23216A1732023-08-14014 August 2023
Consultation Letter to Christine Turner for TMI-2
ML23216A1782023-08-14014 August 2023
Consultation Letter to Steve Letavic for TMI-2
IR 05000289/20230052023-08-14014 August 2023
Constellation Energy Generation, LLC, Three Mile Island Nuclear Station, Unit 1 - NRC Inspection Report 05000289/2023005
ML23216A1752023-08-14014 August 2023
Consultation Letter to Joanna Cain for TMI-2
ML23216A1742023-08-14014 August 2023
Consultation Letter to David Morrison for TMI-2
ML23216A1772023-08-14014 August 2023
Consultation Letter to Rebecca Countess for TMI-2
ML23221A1402023-08-0808 August 2023
(TMI-2), Response to Requests for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5
ML23200A1882023-07-31031 July 2023
TMI-2 Correction Letter Amendment 67
ML23209A7632023-07-28028 July 2023
Letter from PA Shpo to TMI-2 Solutions on Cultural and Historic Impacts of Decommissioning
ML23192A8272023-07-10010 July 2023
TMI-2 Solutions, LLC - Response to Shpo Request for Additional Information for Er Project 2021PR03278.006, TMI-2 Decommissioning Project
ML23167A4642023-07-0505 July 2023
Letter - TMI-2- Exemption 10 CFR Part 20 Append G Issuance
ML23167A0312023-06-28028 June 2023
Acceptance Review and Schedule for the Request for Exemption from a Requirement from 10 CFR 20, Appendix G, Section Iii.E, EPID L-2023-LLE-0016
2024-09-09
[Table view]
Category:Report
MONTHYEARML23073A3982023-03-31031 March 2023
TMI-2 ISFSI Biennial Update Report for 2023
TMI-23-005, Updated Spent Fuel Management Plan2023-03-21021 March 2023
Updated Spent Fuel Management Plan
ML22335A4632022-12-0101 December 2022
Chronology of Significant Events in Operator Licensing Since the Three Mile Island Accident (1979)
ML22101A0792022-03-23023 March 2022
TMI2-EN-RPT-0001, Revision 1, Determination of the Safe Fuel Mass Limit for Decommissioning
TMI-22-008, 2021 Aircraft Movement Data Annual Report for TMI-12022-02-28028 February 2022
2021 Aircraft Movement Data Annual Report for TMI-1
ML22105A0932021-12-16016 December 2021
Attachment 3 - RSCS Technical Support Document (Tsd) No. 21-078 Rev 00 TMI-2 Source Term Limitations and Administrative Controls to Prevent Exceeding the 1 Rem EPA PAG
ML21236A2882021-08-10010 August 2021
TMI-2 Pdms SAR Update 14 & QA Plan (Rev 18 & 19) Biennial Submittal 08-10-21
ML21133A2642021-05-0505 May 2021
Supplemental Information to License Amendment Request Decommissioning Technical Specifications
ML21084A2292021-03-17017 March 2021
Notification of Amended Post-Shutdown Decommissioning Activities Report Accordance with 10 CFR 50.82(a)(7), Revision 4
ML21085A6922021-03-15015 March 2021
Plan for Management of Debris Material
ML21056A0052021-02-25025 February 2021
2020 Aircraft Movement Data Annual Report
ML21133A2652021-02-0101 February 2021
Calculation TMI2-EN-RPT-0002, Revision 0, MCNP Version 6.2 Bias Determination for Low Enrichment Uranium Using the ENDF/B-VIII.0 Cross Section Library
ML18107A2152018-04-10010 April 2018
Biennial 10 CFR 50.59 and Commitment Revision Reports for 2016 and 2017
ML17289A0532017-10-15015 October 2017
Case Study Overview
ML17165A4092017-06-14014 June 2017
T1R22 Refuel Outage MRP-227-A Reactor Internals Scope Deferral Review
RS-16-087, Report of Full Compliance with March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049)2016-06-29029 June 2016
Report of Full Compliance with March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049)
RS-16-104, Mitigating Strategies Flood Hazard Assessment Submittal2016-06-29029 June 2016
Mitigating Strategies Flood Hazard Assessment Submittal
ML15306A5032015-12-17017 December 2015
Closure Evaluation for Report Pursuant to 10 CFR 50.46 Requirements Related to Thermal Conductivity Degradation
ML15223A2152015-08-14014 August 2015
Staff Assessment of Information Provided Pursuant to Title 10 of the Code of Federal Regulations Part 50, Section 50.54(f), Seismic Hazard Reevaluations for Recommendation 2.1 of the NTTF Review of Insights
TMI-15-076, Submittal of TMI White Paper-TMI Bwst Cleanup Path Issue2015-06-22022 June 2015
Submittal of TMI White Paper-TMI Bwst Cleanup Path Issue
ML15043A1442015-02-13013 February 2015
Review of Steam Generator Tube Inspection Report for Fall 2013 Outage
ML14297A4112014-12-19019 December 2014
Letter and Non-Proprietary Safety Evaluation of Reactor Vessel Internals Inspection Plan
RS-14-301, Expedited Seismic Evaluation Process Report (CEUS Sites), Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima.2014-12-17017 December 2014
Expedited Seismic Evaluation Process Report (CEUS Sites), Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima.
RS-14-277, Proposed Alternative to Utilize Code Case N-513-4, Evaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or 3 Piping Section XI, Division 12014-09-24024 September 2014
Proposed Alternative to Utilize Code Case N-513-4, Evaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or 3 Piping Section XI, Division 1
ML14163A0242014-06-10010 June 2014
Response to Request for Additional Information - Review of the Cycle 20 Core Operating Limits Report
ML14189A2852014-04-30030 April 2014
Topical Report 213, 40th Year Reactor Building Tendon Surveillance (Period 10), (Rev 0)
ML14189A2862014-04-17017 April 2014
Final Report for the 40th Year (10th Period) Tendon Surveillance at Three Mile Island, Unit 1
TMI-14-053, Biennial 10 CFR 50.59 and Commitment Revision Report for 2012 and 20132014-04-16016 April 2014
Biennial 10 CFR 50.59 and Commitment Revision Report for 2012 and 2013
RS-14-032, Report RS-14-032, Seismic Walkdown Report in Response to the 50.54(f) Information Request Regarding Fukushima Near-Term Task Force Recommendation 2.3: Seismic, Updated Transmittal 1 (Annex a) for the Three Mile Island Nuclear Station, Uni2014-02-28028 February 2014
Report RS-14-032, Seismic Walkdown Report in Response to the 50.54(f) Information Request Regarding Fukushima Near-Term Task Force Recommendation 2.3: Seismic, Updated Transmittal #1 (Annex a) for the Three Mile Island Nuclear Station, Unit
ML13225A5522013-12-17017 December 2013
Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Order EA-12-049 (Mitigation Strategies)
ML13338A6712013-12-0909 December 2013
Mega-Tech Services, LLC, Technical Evaluation Report Regarding the Overall Integrated Plan for Three Mile Island, Unit 1, TAC MF0803
ML14189A2872013-11-12012 November 2013
TMI 40TH Year Tendon Surveillance, Tendon No. 1-146-34, Tendon End Buddress 4
TMI-14-061, 40th Year Tendon Surveillance Engineering Report (Topical Report 213), Precision Surveillance Corporation in-Service Inspection Quality Control Procedure, Monitoring Tendon Force (Lift-Offs)2013-09-0303 September 2013
40th Year Tendon Surveillance Engineering Report (Topical Report 213), Precision Surveillance Corporation in-Service Inspection Quality Control Procedure, Monitoring Tendon Force (Lift-Offs)
TMI-13-107, Attachment 1 - Areva Document No. ANP-3102Q1, Response to NRC Ria Regarding License Amendment Request to Update Pressure -Temperature Limit Curves for Three-Mile Island Unit 1, Revision 0, Dated August 20132013-08-31031 August 2013
Attachment 1 - Areva Document No. ANP-3102Q1, Response to NRC Ria Regarding License Amendment Request to Update Pressure -Temperature Limit Curves for Three-Mile Island Unit 1, Revision 0, Dated August 2013
ML13232A2172013-07-31031 July 2013
Attachment 2 - Areva Document No. ANP-3102, Revision 3,Three-Mile Island Unit 1 Appendix G Pressure-Temperature Limits at 50.2 EFPY with Mur, Revision 3, Dated July 2013
TMI-13-041, Post-Shutdown Decommissioning Activities Report Submittal2013-06-28028 June 2013
Post-Shutdown Decommissioning Activities Report Submittal
TMI-12-148, Plant-Specific Path and Schedule for Resolution of Generic Letter 2004-022013-05-16016 May 2013
Plant-Specific Path and Schedule for Resolution of Generic Letter 2004-02
IR 05000456/20132022013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
ML13008A2192013-01-31031 January 2013
U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000454/20132022013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000461/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000237/20132022013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000373/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000352/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000219/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000277/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000254/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000272/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000289/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
ML12362A0422012-11-0707 November 2012
Report No. 12Q0108.70-R-001, Rev. 1, Seismic Walkdown Report in Response to the 50.54(f) Information Request Regarding Fukushima Near-Term Task Force Recommendation 2.3: Seismic for Three Mile Island Unit 1, Page C-1 Through Page C-161
2023-03-31
[Table view]
Category:Miscellaneous
MONTHYEARTMI-23-005, Updated Spent Fuel Management Plan2023-03-21021 March 2023
Updated Spent Fuel Management Plan
ML22335A4632022-12-0101 December 2022
Chronology of Significant Events in Operator Licensing Since the Three Mile Island Accident (1979)
TMI-22-008, 2021 Aircraft Movement Data Annual Report for TMI-12022-02-28028 February 2022
2021 Aircraft Movement Data Annual Report for TMI-1
ML21085A6922021-03-15015 March 2021
Plan for Management of Debris Material
ML21056A0052021-02-25025 February 2021
2020 Aircraft Movement Data Annual Report
ML18107A2152018-04-10010 April 2018
Biennial 10 CFR 50.59 and Commitment Revision Reports for 2016 and 2017
ML17289A0532017-10-15015 October 2017
Case Study Overview
ML17165A4092017-06-14014 June 2017
T1R22 Refuel Outage MRP-227-A Reactor Internals Scope Deferral Review
RS-16-104, Mitigating Strategies Flood Hazard Assessment Submittal2016-06-29029 June 2016
Mitigating Strategies Flood Hazard Assessment Submittal
ML15306A5032015-12-17017 December 2015
Closure Evaluation for Report Pursuant to 10 CFR 50.46 Requirements Related to Thermal Conductivity Degradation
ML15223A2152015-08-14014 August 2015
Staff Assessment of Information Provided Pursuant to Title 10 of the Code of Federal Regulations Part 50, Section 50.54(f), Seismic Hazard Reevaluations for Recommendation 2.1 of the NTTF Review of Insights
TMI-15-076, Submittal of TMI White Paper-TMI Bwst Cleanup Path Issue2015-06-22022 June 2015
Submittal of TMI White Paper-TMI Bwst Cleanup Path Issue
ML15043A1442015-02-13013 February 2015
Review of Steam Generator Tube Inspection Report for Fall 2013 Outage
ML14297A4112014-12-19019 December 2014
Letter and Non-Proprietary Safety Evaluation of Reactor Vessel Internals Inspection Plan
RS-14-301, Expedited Seismic Evaluation Process Report (CEUS Sites), Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima.2014-12-17017 December 2014
Expedited Seismic Evaluation Process Report (CEUS Sites), Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima.
ML14163A0242014-06-10010 June 2014
Response to Request for Additional Information - Review of the Cycle 20 Core Operating Limits Report
TMI-14-053, Biennial 10 CFR 50.59 and Commitment Revision Report for 2012 and 20132014-04-16016 April 2014
Biennial 10 CFR 50.59 and Commitment Revision Report for 2012 and 2013
TMI-13-041, Post-Shutdown Decommissioning Activities Report Submittal2013-06-28028 June 2013
Post-Shutdown Decommissioning Activities Report Submittal
TMI-12-148, Plant-Specific Path and Schedule for Resolution of Generic Letter 2004-022013-05-16016 May 2013
Plant-Specific Path and Schedule for Resolution of Generic Letter 2004-02
IR 05000456/20132022013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000272/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000254/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000277/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000219/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000352/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000289/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000373/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
ML13008A2192013-01-31031 January 2013
U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000454/20132022013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000461/20132012013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
IR 05000237/20132022013-01-31031 January 2013
Exelon Generation Co., LLC, U.S. Nuclear Regulatory Commission (NRC) Office of Investigations (01) Investigation; Summary of 01 Report No. 3-2010-034; NRC Inspection Report Conference Letter - Licensee
ML12178A2152012-08-0202 August 2012
Closeout of Bulletin 2011-01 Migrating Strategies.
E910-11-007, Gpu Nuclear, TMI 2 Defueling Completion Report2011-04-11011 April 2011
Gpu Nuclear, TMI 2 Defueling Completion Report
ML1023505272010-08-18018 August 2010
Buried Piping - Inspecting Something You Can'T See
TMI-10-029, Biennial 10 CFR 50.59 and Commitment Revision Reports for 2008 and 20092010-04-15015 April 2010
Biennial 10 CFR 50.59 and Commitment Revision Reports for 2008 and 2009
ML0828804502008-10-14014 October 2008
2008 PA Fishing Summary - Summary of Fishing Regulations and Laws
ML0824101022008-06-12012 June 2008
Report of Tornadoes in Dauphin County, PA Between 01/01/1950 and 05/31/2008, NCDC
ML0815801742008-05-30030 May 2008
License Renewal Environmental Impact Statement
ML0824100852008-05-0101 May 2008
Comprehensive Plan for the Water Resources of the Susquehanna River Basin, Draft
ML0819807102008-04-0303 April 2008
C2-WHC 2005 - Site Assessment and Wildlife Management Opportunities Report for Exelon Corporation'S Three Mile Island Generating Station. October
ML0830502322008-03-11011 March 2008
Pjm 2007 State of the Market Report
ML0816106632008-02-14014 February 2008
Biennial 10 CFR 50.59 and Pdms SAR Report for Years 2006 & 2007
ML0612100392006-04-19019 April 2006
Biennial 10 CFR 50.59 and Commitment Revision Report for 2004 and 2005
ML0505301682005-02-17017 February 2005
Background Discussion Material for February 24-25, 2005 NRC Meeting Relating to Replacement for BAW-2374, Revision 1, Evaluation of OTSG Thermal Loads During Hot Leg Loca.
ML0309006042003-03-19019 March 2003
Additional Information Regarding Notice of Proposed Amendments to Trust Agreement to Implement Assignment of Decommissioning Trust Funds for Amergen Energy Company, LLC
ML0303506252003-01-23023 January 2003
Request for NRC Written Consent to Proposed Amendments to Trust Agreement to Implement Assignment of Decommissioning Trust Funds for Amergen Energy Company, LLC
ML0231803602002-11-0404 November 2002
(TMI-1) Emergency Notification System Warning Sirens
ML0224802942002-08-28028 August 2002
Fitness-for-Duty Program Performance Data (FFD) for the Period - January 2002 Through June 2002
ML0224901882002-08-27027 August 2002
Fire Hazards Analysis Report (Fhar), Rev 20, Appendix R Evaluation Report, Cables & Components in Fire Area/Zone, Volume II, Attachment 3-7
ML0224901792002-08-27027 August 2002
Fire Hazards Analysis Report (Fhar), Rev 20, Appendix R Evaluation Report, Component Availability for a Fire in Fire Area/Zone, Volume II, Attachments 3-51 - 3-61
2023-03-21
[Table view] |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Mr. Bryan C. Hanson President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555 December 17, 2015
SUBJECT:
THREE MILE ISLAND NUCLEAR STATION, UNIT 1 -CLOSURE EVALUATION FOR REPORT PURSUANT TO 10 CFR 50.46 REQUIREMENTS RELATED TO THERMAL CONDUCTIVITY DEGRADATION (CAC NO. MF5564)
Dear Mr. Hanson:
By letter dated December 22, 2014, as supplemented by letter dated April 6, 2015 (Agencywide Documents Access and Management System Accession Nos. ML 14356A342 and ML 15097A125, respectively),
Exelon Generation
- Company, LLC submitted a report pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3) for the Three Mile Island Nuclear Station, Unit 1 (TMl-1 ). This report described a significant error identified in the emergency core cooling system evaluation model and an estimate of the effect of the error on the predicted peak cladding temperature for TMl-1. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of this report. Based on this evaluation, the NRC staff has determined that the report, as supplemented, satisfies the reporting requirements of 10 CFR 50.46(a)(3) for TMl-1. A copy of the staff's closure evaluation is enclosed.
This completes the NRC staff's efforts associated with Cost Activity Code No. MF5564. Should you have any questions, please contact me at (301) 415-1022 or Robert.Gladney@nrc.gov.
Docket No. 50-289
Enclosure:
Staff's Closure Evaluation cc w/enclosure:
Distribution via Listserv Sincerely, Robert L. Gladney, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 CLOSURE EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION STAFF RELATED TO REPORT PURSUANT TO 10 CFR 50.46 EXELON GENERATION COMPANY.
LLC THREE MILE ISLAND NUCLEAR STATION.
UNIT 1 DOCKET NO. 50-289
1.0 INTRODUCTION
By letter dated December 22, 2014, as supplemented by letter dated April 6, 2015 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML 14356A342 and ML 15097A125, respectively),
Exelon Generation
- Company, LLC (Exelon, the licensee) submitted a report pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3) for the Three Mile Island Nuclear Station, Unit 1 (TMl-1 ). This report described a significant error identified in the emergency core cooling system (ECCS) evaluation model (EM) and an estimate of the effect of the error on the predicted peak cladding temperature (PCT) for TMl-1. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of the report and determined, as discussed below, that the report, as supplemented, satisfies the reporting requirements of 10 CFR 50.46(a)(3) for TMl-1. 2.0 REGULATORY EVALUATION 2.1 Regulatory Requirements Specific requirements with regard to ECCS for light-water nuclear power reactors are found in 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors."
Within this regulation, 10 CFR 50.46(a)(1
)(i) requires, in part, that, "ECCS cooling performance must be calculated in accordance with an acceptable evaluation model." Paragraph (a)(3)(i) of 10 CFR 50.46 requires licensees to "estimate the effect of any change to or error in an acceptable evaluation model, or in the application of such a model, to determine if the change or error is significant."
For the purposes of 10 CFR 50.46, a significant change or error is one that results in a calculated PCT difference of more than 50 degrees Fahrenheit
(°F) "from the temperature calculated for the limiting transient using the last acceptable model, or is [an accumulation]
of changes and errors such that the sum of the absolute magnitudes of the respective temperature changes is greater than 50 °F." For each change to or error discovered in an acceptable EM, or in the application of such a model, 10 CFR 50.46(a)(3)(ii) requires the affected licensee to report the nature of the change Enclosure or error and its estimated effect on the limiting ECCS analysis to the NRC at least annually.
If the change or error is significant, the licensee is required to provide this report within 30 days. The report is to include "a proposed for providing a reanalysis or taking other action as may be needed to show compliance with [10 CFR] 50.46 requirements."
Paragraph (b) of 1 O CFR 50.46 provides the acceptance criteria for ECCS performance.
In particular, 10 CFR 50.46(b)(1
), "Peak cladding temperature,"
states, "The calculated maximum fuel element cladding temperature shall not exceed 2200° F." 2.2 Background The NRG-approved AREVA Inc. (AREVA) proprietary topical report BAW-10192P-A, "BWNT Loss-of-Coolant Accident Evaluation Model for Once-Through Steam Generator Plants" (hereinafter "BWNT LOCA EM"), 1 is the acceptable EM used to evaluate ECCS performance at TMl-1. In accordance with 10 CFR Part 21, "Reporting of Defects and Noncompliance,"
AREVA reported an error in its loss-of-coolant accident (LOCA) analysis for plants with a Babcock & Wilcox design, including TMl-1, by a letter to the NRC dated December 16, 2014 (ADAMS Accession No. ML 14351A308).
In its report, AREVA stated that the current fuel "thermal conductivity model does not adequately represent the change in conductivity with burnup for the fuel." This defect relates to the uranium fuel thermal conductivity models in the fuel thermal-mechanical codes TAC032 and GDTAC0,3 which are part of the BWNT LOCA EM. The defect resulted in an under-prediction of the large-break PCT at TMl-1. To compensate for the under-prediction of PCT, AREVA stated that each affected plant, including TMl-1, was advised to reduce fuel linear heat rate (LHR) by 2 kilowatts per foot (kW/ft).
Based on AREVA's notification, Exelon submitted its December 22, 2014, letter to notify the NRC that the defect constituted an error in the ECCS EM for TMl-1. The licensee's letter provided (1) a description of the nature of the error and its estimated effect on the PCT; (2) a summary of actions taken to ensure compliance with 10 CFR 50.46 requirements, including implementing the 2 kW/ft LHR reduction; and (3) a commitment that a large break LOCA (LBLOCA) reanalysis, accounting for the effects of thermal conductivity degradation (TCD), would be performed for TMl-1 by March 31, 2017. (This commitment was superseded by the commitment submitted in the April 6, 2015, letter, which is described in Section 3.2 of this evaluation.)
The December 22, 2014, letter stated that the TCD-related defect was estimated to cause the PCT at TMl-1 to increase 393 °F. The licensee's implementation of a 2 kW/ft LHR reduction was estimated to offset the TCD effect by reducing the PCT by 375 °F. Therefore, the predicted 1 BAW-10192P-A describes the ECCS EM; however, the EM requires use of input from approved thermal-mechanical models. Plant-specific application is described in further detail in BAW-10179P-A, "Safety Criteria and Methodology for Acceptable Cycle Reload Analyses."
2 AREVA NP Licensing Topical Report BAW-10162P-A, "TAC03 -Fuel Pin Thermal Analysis Code." 3 AREVA NP Licensing Topical Report BAW-10184P-A, "GDTACO -Urania Gadolinia Fuel Pin Thermal Analysis Code." PCT for TMl-1 increases from 1,890 °F to 1,908 °F, which remains less than the regulatory limit of 2200 °F. 2.3 Regulatory Commitment The licensee provided the following commitment in its December 22, 2014, letter. Exelon will perform a full LBLOCA reanalysis for TMI Unit 1 by March 31, 2017. The effects of fuel pellet thermal conductivity degradation will be accounted for by use of a fuel temperature uncertainty adjustment factor based on COPERNIC2.
- However, in its April 6, 2015, letter, the licensee provided the following new commitment, which supersedes its December 22, 2014, commitment:
The full LBLOCA reanalysis will be completed within 21 months following NRC issuance of the final Safety Evaluation Report (SER) for BAW-10179 Revision 9, which incorporates by reference the supplement to BAW-10192P-A Revision
- 0. Therefore, in its April 6, 2015, letter, the licensee committed to completing this reanalysis within 21 months following NRC issuance of a final SER, approving BAW-10179, Revision 9, for use. The NRC staff determined that this commitment revision is acceptable as it does not affect the outcome of the NRC staff's review or the licensee's compliance with the regulations.
3.0 TECHNICAL EVALUATION 3.1 Use of an Acceptable Evaluation Model for Reanalysis The December 22, 2014, letter indicated that Exelon would complete a full LBLOCA reanalysis incorporating the effects of TCD by March 31, 2017. This commitment was superseded by a commitment in the April 6, 2015, letter that indicated that the reanalysis will be completed "within 21 months following NRC issuance of the final Safety Evaluation Report (SER) for BAW-10179, Revision 9, which incorporates by reference the supplement to BAW-10192P-A, Revision O." Section 4.3.2.3 of the BWNT LOCA EM requires licensees to use NRG-approved fuel thermal-mechanical models to be consistent with the topical report. The fuel temperature uncertainty values used in TAC03 and GDTACO are specified in the NRG-approved fuel performance methodology documented in BAW-10162P-A and BAW-10184P-A.
The AREVA report identified that these uncertainty values need to be modified in order to account for TCD. In its April 6, 2015, letter, the licensee stated that AREVA will develop a supplement to its BWNT LOCA EM and submit it for NRC review and approval.
4 The licensee stated that the supplement will describe the modifications to the BWNT LOCA EM necessary for correction of the TCD issue. Based on this information, the NRC staff determined that the licensee has 4 By letter dated November 25, 2015 (ADAMS Accession No. ML 15337 A242), AREVA submitted Request for Review and Approval of BAW-10192PA-OO, Supplement 1, Revision 0, "BWNT LOCA BWNT Loss-of-Coolant Accident Evaluation Model for Once-Through Steam Generator Plants." adequately described how it will ensure that ECCS cooling performance is calculated using an acceptable EM. 3.2 Adequacy of Reanalysis Scope As discussed above, the licensee stated that the TCD-related model changes will be incorporated as a supplement to the BWNT LOCA EM. The December 22, 2014, letter states that, "the reanalysis will address the significant EM error corrections to cover [in addition to the TCD-related error correction]
the ECCS bypass error correction and column weldment modeling changes."
Based on the magnitude of the estimated effect of a TCD correction on the TMl-1 ECCS evaluation, in addition to these additional, significant model changes and error corrections, the NRC staff determined that these model revisions would significantly change the predicted ECCS performance for TMl-1. Regarding the evaluation of ECCS performance, 10 CFR 50.46(a)(1
)(i) states, in part, that ECCS cooling performance "must be calculated for a number of postulated loss-of-coolant accidents of different sizes, locations, and other properties sufficient to provide assurance that the most severe postulated loss-of-coolant accidents are calculated."
In its April 6, 2015, letter, the licensee stated: The revised LBLOCA analyses will include a review of the current LBLOCA analyses to determine if the conclusion of the previous evaluation of a spectrum of break sizes, locations, and other properties is sufficient to verify the selection of the most severe hypothetical case. If the review determines that additional calculations are required to select the most severe hypothetical case, then the additional calculations will be performed.
Based on NRC staff experience, various issues associated with an ECCS evaluation may be addressed using an evaluation of a spectrum of break sizes, locations, and other properties, and this evaluation may be performed on a more general, simplified basis. Once a set of generally limiting properties is identified, a more detailed, plant-specific analysis identifies the exact limiting properties and determines the results for comparison against the 1 O CFR 50.46(b) acceptance criteria.
The licensee's statement above is consistent with this practice.
Based on the discussion above, the staff determined that the licensee adequately described how it will provide assurance that the most severe postulated LOCAs are calculated.
3.3 Technical Specification (TS) Impacts The TMl-1 TS 6.9.5.2 requires, in part: The analytical methods used to determine the core operating limits addressed by the individual Technical Specifications shall be those previously reviewed and approved by the NRC for use at TMl-1, specifically:
(1) BAW-10179 P-A, "Safety [Criteria]
5 and Methodology for Acceptable Cycle Reload Analyses."
The current revision level shall be specified in the COLR. 5 Note that the word, "criteria,"
appears to be omitted from the TS core operating limit report reference. The BWNT LOCA EM is incorporated into BAW-10179P-A by reference.
In a letter dated March 8, 2015 (ADAMS Accession No. ML 15020A737),
the NRC staff noted that the application of TCD-corrected fuel temperature uncertainties to TAC03 and GDTACO may be inconsistent with Section 9.2.3, "Steady-State Fuel Data Input to LOCA EMs," of BAW-10179P-A.
In its April 6, 2015, letter, the licensee stated that AREVA would also revise BAW-10179P-A to incorporate a reference to the BWNT LOCA EM supplement, and this revision would be submitted to the NRC for review and approval.
The licensee stated that it will notify the NRC when the reanalysis is complete.
Based on the discussion above, the NRC staff determined that the licensee has adequately described how it will comply with TS 6.9.5.2 with the application of the BWNT LOCA EM supplement.
4.0 CONCLUSION
Based on its review, the NRC staff concluded that Exelon's report, as supplemented, satisfies the reporting requirements of 1 O CFR 50.46(a)(3).
The report described the nature of the TCD-related error and provided its estimated effect on the PCT for the limiting ECCS evaluation.
The report also indicated that the licensee took action to reduce LHR limits to compensate for the effect of TCD and showed that the predicted PCT would remain below 2200 °F. The report, as supplemented, included a proposed schedule for performing reanalysis and taking other actions, as needed, to comply with 10 CFR 50.46 requirements.
Principal Contributors:
B. Parks J. Whitman R. Gladney Date: December 17, 2015 December 17, 2015 Mr. Bryan C. Hanson President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
THREE MILE ISLAND NUCLEAR STATION, UNIT 1 -CLOSURE EVALUATION FOR REPORT PURSUANT TO 10 CFR 50.46 REQUIREMENTS RELATED TO THERMAL CONDUCTIVITY DEGRADATION (CAC NO. MF5564)
Dear Mr. Hanson:
By letter dated December 22, 2014, as supplemented by letter dated April 6, 2015 (Agencywide Documents Access and Management System Accession Nos. ML 14356A342 and ML 15097A125, respectively),
Exelon Generation
- Company, LLC submitted a report pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3) for the Three Mile Island Nuclear Station, Unit 1 (TMl-1).
This report described a significant error identified in the emergency core cooling system evaluation model and an estimate of the effect of the error on the predicted peak cladding temperature for TMl-1. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of this report. Based on this evaluation, the NRC staff has determined that the report, as supplemented, satisfies the reporting requirements of 10 CFR 50.46(a)(3) for TMl-1. A copy of the staff's closure evaluation is enclosed.
This completes the NRC staff's efforts associated with Cost Activity Code No. MF5564. Should you have any questions, please contact me at (301) 415-1022 or Robert.Gladney@nrc.gov.
Docket No. 50-289
Enclosure:
Staff's Closure Evaluation cc w/enclosure:
Distribution via Listserv DISTRIBUTION:
PUBLIC LPL 1-2 R/F BParks, NRR Sincerely, IRA/ Robert L. Gladney, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation RidsRgn1 MailCenter Resource RidsACRS_MailCTR Resource RidsNrrDssSnpb Resource
- JWhitman, NRR RidsNrrDssSrxb Resource RidsNrrPMThreeMilelsland Resource RidsNrrDorlLpl1-2 Resource RidsNrrLALRonewicz Resource ADAMS Accession No.: ML 15306A503 OFFICE DORL/LPL 1-2/PM DORL/LPL 1-2/LA DSS/SNPB/BC DSS/SRXB/BC DORL/LPL 1-2/BC DORL/LPL 1-2/PM NAME RGladney LRonewicz JDean CJackson DBroaddus RGladney DATE 12/17/2015 11/27/2015 11/05/2015 11/12/2015 12/17/2015 12/17/2015 OFFICIAL RECORD COPY
