Letter Sequence RAI |
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TAC:ME3587, Relocate Surveillance Frequencies to Licensee Control - RITSTF Initiative 5B (Approved, Closed) |
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MONTHYEARTMI-10-021, Application for Technical Specifications Change Regarding Risk-Informed Justification for the Relocation of Specific Surveillance Frequency Requirements to a Licensee Controlled Program (Adoption of TSTF-425, Revision 3)2010-03-24024 March 2010 Application for Technical Specifications Change Regarding Risk-Informed Justification for the Relocation of Specific Surveillance Frequency Requirements to a Licensee Controlled Program (Adoption of TSTF-425, Revision 3) Project stage: Request ML1011002162010-04-20020 April 2010 Acceptance Review for TMI-1 LAR Regarding Adoption of TSTF-425, Surveillance Frequency Control Program, TAC ME3587 Project stage: Acceptance Review ML1016805952010-06-17017 June 2010 Electronic Transmission, Draft Request for Additional Information Regarding License Amendment Request to Adopt TSTF-425, Relocation of Surveillance Frequencies to a Licensee Controlled Program Project stage: Draft RAI ML1016806472010-07-0202 July 2010 Request for Additional Information Regarding License Amendment Request to Adopt TSTF-425, Relocation of Surveillance Frequencies to a Licensee Controlled Program Project stage: RAI TMI-10-072, Response to Request for Additional Information, Application for Technical Specifications Change Risk-Informed Justification for Relocation of Specific Surveillance Frequency Requirements to Licensee Controlled Program2010-07-29029 July 2010 Response to Request for Additional Information, Application for Technical Specifications Change Risk-Informed Justification for Relocation of Specific Surveillance Frequency Requirements to Licensee Controlled Program Project stage: Response to RAI ML1022903942010-08-17017 August 2010 Electronic Transmission, Draft Request for Additional Information Regarding License Amendment Request to Adopt TSTF-425, Relocation of Surveillance Frequencies to a Licensee Controlled Program Project stage: Draft RAI ML1023000782010-09-0808 September 2010 Request for Additional Information Regarding License Amendment Request to Adopt TSTF-425, Relocation of Surveillance Frequencies to a Licensee Controlled Program Project stage: RAI TMI-10-080, Response to Request for Additional Information, Application for Technical Specifications Change Regarding Risk-Informed Justification for the Relocation of Specific Surveillance Frequency Requirements to a Licensee Controlled2010-09-27027 September 2010 Response to Request for Additional Information, Application for Technical Specifications Change Regarding Risk-Informed Justification for the Relocation of Specific Surveillance Frequency Requirements to a Licensee Controlled Project stage: Response to RAI ML1031200692011-01-12012 January 2011 Issuance of Amendment Request to Relocate Surveillance Frequencies to a Licensee Controlled Program Project stage: Approval 2010-07-29
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Category:Letter
MONTHYEARIR 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 ML24120A2552024-04-29029 April 2024 Annual Radiological Environmental Operating Report ML24121A2472024-04-29029 April 2024 and Three Mile Island, Unit 2 - 2023 Occupational Radiation Exposure Annual 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 ML24065A0042024-03-28028 March 2024 Submittal of 2023 Aircraft Movement Data Annual 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 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)) ML24074A3922024-03-14014 March 2024 Response to Request for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5 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 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 ML23354A2112023-12-20020 December 2023 Response to Request for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5 ML23354A2062023-12-20020 December 2023 (TMI-2), Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation 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 ML23216A1772023-08-14014 August 2023 Consultation Letter to Rebecca Countess for TMI-2 ML23216A1742023-08-14014 August 2023 Consultation Letter to David Morrison for TMI-2 ML23216A1752023-08-14014 August 2023 Consultation Letter to Joanna Cain for TMI-2 ML23216A1732023-08-14014 August 2023 Consultation Letter to Christine Turner for TMI-2 IR 05000289/20230052023-08-14014 August 2023 Constellation Energy Generation, LLC, Three Mile Island Nuclear Station, Unit 1 - NRC Inspection Report 05000289/2023005 ML23216A1782023-08-14014 August 2023 Consultation Letter to Steve Letavic for TMI-2 ML23221A1402023-08-0808 August 2023 (TMI-2), Response to Requests for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5 ML23200A1882023-07-31031 July 2023 TMI-2 Correction Letter Amendment 67 ML23209A7632023-07-28028 July 2023 Letter from PA Shpo to TMI-2 Solutions on Cultural and Historic Impacts of Decommissioning ML23192A8272023-07-10010 July 2023 TMI-2 Solutions, LLC - Response to Shpo Request for Additional Information for Er Project 2021PR03278.006, TMI-2 Decommissioning Project ML23167A4642023-07-0505 July 2023 Letter - TMI-2- Exemption 10 CFR Part 20 Append G Issuance ML23167A0312023-06-28028 June 2023 Acceptance Review and Schedule for the Request for Exemption from a Requirement from 10 CFR 20, Appendix G, Section Iii.E, EPID L-2023-LLE-0016 ML23171B0222023-06-19019 June 2023 (TMI-2) - Notification Pursuant to 10 CFR 72.140(d) Regarding Application of Previously Approved TMI-2 Quality Assurance Program to Independent Spent Fuel Storage Installation Activities ML23138A0662023-05-17017 May 2023 TMI-2 NHPA Section 106 Shpo Letter to NRC 5-17-23 ML23137A2822023-05-17017 May 2023 (TMI-2), Request for Exemption from 10 CFR 20, Appendix G, Section Iii.E ML23026A3132023-05-0202 May 2023 Issuance of Exemption from 10 CFR 70.24 (EPID-L-2023-LLE-0003) ML23122A1842023-05-0101 May 2023 Shpo_Er_Summary_Letter 2024-06-03
[Table view] Category:Request for Additional Information (RAI)
MONTHYEARML24157A3672024-06-13013 June 2024 Updated Post-Shutdown Decommissioning Activities Report Request for Additional Information Transmittal Letter ML24011A2352024-01-11011 January 2024 Eco Request for Additional Information for 2023 License Amendment Request 1-11-24 ML23187A0202023-06-29029 June 2023 TMI Unit 2 RAI Related to the Amended Post-Shutdown Decommissioning Activities Report ML23187A0332023-06-29029 June 2023 TMI Unit 2, PSDAR Rev. 5 RAIs ML23082A3432023-03-31031 March 2023 Enclosure - RAI - Three Mile Island, Unit 2 - Acceptance Review and Request for Additional Information for the Historic and Cultural Resources License Amendment Request - EPID: 2023-LLA-0026 ML22357A0142022-12-22022 December 2022 NRC Request for Additional Information Related to the TMI-2 Pdms Transition License Amendment Request ML22210A0882022-07-29029 July 2022 Enclosure - Three Mile Island, Unit No. 2 - Request for Additional Information for Requested Licensing Action Regarding Decommissioning Technical Specifications ML22143A8902022-05-23023 May 2022 Request for Additional information- TMI-1 ISFSI Only Physical Security License Amendment Request ML22125A0122022-04-28028 April 2022 Clarification RAI Partial Response Email from C Smith to a Snyder ML22110A0202022-04-19019 April 2022 Unit 1 Request for Additional Information ML22038A9362022-02-0707 February 2022 TMI2 Accident Analyses Questions ML21256A1902021-09-10010 September 2021 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding License Transfer Application ML21144A2132021-05-24024 May 2021 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding License Transfer Application ML20164A0902020-06-10010 June 2020 Request for Additional Information Related to TMI-1 License Amendment Request to Delete Permanently Defueled Technical Specification 3/4.1.4 (L-2019-LLA-0250) ML19319B2082019-11-15015 November 2019 NRR E-mail Capture - Request for Additional Information Related to TMI-1 Request for Exemption from Portions of 10 CFR 50.47 and Part 50 Appendix E (L-2019-LLA-0216) ML19179A0612019-07-19019 July 2019 Three Mile Point 1 - Supplemental Information Needed to Proposed Alternative to Use ASME Code Case N-879 ML18220A7832018-08-0707 August 2018 NRR E-mail Capture - Request for Additional Information Related to TMI Fall 2017 Steam Generator Tube Inspection Report ML18212A2712018-07-31031 July 2018 NRR E-mail Capture - Request for Additional Information Related to Amendment Regarding Decommissioning ERO Staffing Changes ML17285B1962017-10-27027 October 2017 Request for Additional Information Regarding Generic Letter 2016-01, Monitoring of Neutron-Absorbing Materials in Spent Fuel Pools. ML17062A4912017-03-0303 March 2017 NRR E-mail Capture - Exelon Generation Company, LLC - Request for Additional Information Regarding Fleet Alternative to RPV Threads in Flange Examination (CAC Nos. MF8712-MF8729) ML16356A4802016-12-21021 December 2016 NRR E-mail Capture - RAIs on TMI License Amendment Request for Approval of Changes to the Three Mile Island Nuclear Station Emergency Plan Related to Staffing ML16337A0072016-12-0101 December 2016 NRR E-mail Capture - Draft RAIs Three Mile Island Nuclear Station, Units 1 and 2, License Amendment Request for Approval of Changes to the Three Mile Island Nuclear Station Emergency Plan Related to Staffing ML16287A4042016-10-11011 October 2016 Notification of Conduct of a Triennial Fire Protection Baseline Inspection ML15230A5332015-08-18018 August 2015 Draft Request for Additional Information ML15020A7372015-03-0808 March 2015 Request for Additional Information Regarding Related to December 22, 2014, Report Submitted Pursuant to 10 CFR 50.46 ML14307A1172014-11-14014 November 2014 Request for Additional Information Regarding Relief Request RR-14-01 Concerning Alternative Root Mean Square Depth Sizing Requirements ML14240A4122014-09-0404 September 2014 Request for Additional Information Regarding License Amendment Request to Eliminate Certain Technical Specification Reporting Requirements (Tac MF0628) ML14134A3222014-05-22022 May 2014 Request for Additional Information Regarding Review of Three Mile Island Nuclear Station Unit 1 Cycle 20 Core Operating Limits Report ML14134A1722014-05-14014 May 2014 Draft RAIs in Support of NRC Staff Review of TMI Cycle 20 COLR ML14052A2592014-02-27027 February 2014 Request for Additional Information Regarding Proposed License Amendment Request to Revise Technical Specification Reporting Requirements ML14030A5832014-01-29029 January 2014 Draft Request for Additional Information Proposed Revision to Technical Specifications Reporting Requirements Exelon Generation Company, LLC Three Mile Island Nuclear Station, Unit 1 ML13266A2852013-10-21021 October 2013 Request for Additional Information on Three Mile Island Nuclear Station Unit 2 - post-shutdown Decommissioning Activities Report ML13276A6492013-10-0303 October 2013 Notification of Conduct of a Triennial Fire Protection Baseline Inspection ML13269A1792013-09-25025 September 2013 Draft Request for Additional Information ML13253A2252013-09-10010 September 2013 Draft Request for Additional Information ML13249A2072013-09-0505 September 2013 Draft Request for Additional Information ML13193A1752013-07-22022 July 2013 Request for Additional Information Regarding Revision to Pressure and Temperature Limit Curves and Exemption Request for Initial Reference Temperature Values ML13196A3382013-07-15015 July 2013 2013 Decommissioning Fund Report RAI ML13193A1452013-07-12012 July 2013 Electronic Transmission, Draft Request for Additional Information Regarding Proposed Revision to Pressure and Temperature Limit Curves and Exemption Request for Initial Reference Temperature Values (TAC Nos. MF0425 & MF0426) ML13176A4702013-06-26026 June 2013 Request for Additional Information Regarding Overall Integrated Plan in Response to Order Number EA-12-051, Reliable Spent Fuel Pool Instrumentation ML13177A3902013-06-26026 June 2013 Electronic Transmission, Draft Request for Additional Information Regarding Overall Integrated Plan in Response to Order Number EA-12-051, Reliable Spent Fuel Pool Instrumentation ML13066A2442013-03-19019 March 2013 Request for Additional Information Regarding Fifth Inservice Test Interval Relief Request PR-01 Nuclear Services Closed Cooling Water Flow Measurement ML13066A1262013-03-0707 March 2013 Electronic Transmission, Draft Request for Additional Information Regarding Fifth Inservice Test Interval Relief Request PR-01 Nuclear Services Closed Cooling Water Flow Measurement ML13044A3212013-03-0505 March 2013 Request for Additional Information Regarding 30-Day Report for Emergency Core Cooling System Model Changes Pursuant to the Requirements of 10 CFR 50.46 ML13045A6432013-02-25025 February 2013 Request for Additional Information Regarding Relief Request VR-01, Associated with the Fifth Inservice Testing Interval ML13051A3852013-02-25025 February 2013 Request for Additional Information Regarding End-of-Interval Relief Request RR-12-01, Pressure Nozzle-to-Head Weld Exams ML13050A6362013-02-20020 February 2013 Draft RAI Memo ML13044A3122013-02-13013 February 2013 Electronic Transmission, Draft Request for Additional Information Regarding 30-Day Report for Emergency Core Cooling System Model Changes Pursuant to the Requirements of 10 CFR 50.46 ML13044A6652013-02-13013 February 2013 Electronic Transmission, Draft Request for Additional Information Regarding Relief Request VR-01, Associated with the Fifth Inservice Testing Interval ML12306A4812012-11-19019 November 2012 Request for Additional Information Regarding 2011 Steam Generator Tube Inspection Report 2024-06-13
[Table view] |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555*0001 July 2,2010 Mr. Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
THREE MILE ISLAND NUCLEAR STATION, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO ADOPT TSTF-425, RELOCATION OF SURVEILLANCE FREQUENCIES TO A LICENSEE CONTROLLED PROGRAM (TAC NO. IVIE3587)
Dear Mr. Pacilio:
By letter dated March 24, 2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML100840205), Exelon Generation Company, LLC (Exelon, the licensee) submitted a license amendment request (LAR) proposing to revise the Technical Specifications (TSs) for Three Mile Island Nuclear Station, Unit 1. The proposed changes would relocate certain surveillance frequencies to a licensee controlled program through the implementation of Nuclear Energy Institute (NEI) 04-10, "Risk-Informed Technical Specifications Initiative 5b, Risk-Informed Method for Control of Surveillance Frequencies." According to the submittal, the changes are consistent with U.S. Nuclear Regulatory Commission (NRC) approved Technical Specifications Task Force (TSTF) Standard Technical Specifications (STSs) change TSTF-425, "Relocate Surveillance Frequencies to Licensee Control - Risk Informed Technical Specifications Task Force Initiative 5b," Revision 3.
The Nuclear Regulatory Commission staff has been reviewing the response and has determined that additional information is needed to complete its review. The specific questions are found in the enclosed request for additional information (RAI). The questions were sent via electronic transmission on June 17, 2010, to Mr. Glenn Stewart, of your staff. The draft questions were sent to ensure that the questions were understandable, the regulatory basis for the questions was clear, and to determine if the information was previously docketed. The draft questions were discussed in a teleconference with your staff on June 23, 2010, where a minor wording change was made to RAI question 2. It was agreed that a response to this RAI would be submitted by July 30, 2010. If a response is not received by that date, the license amendment request will be subject to denial, pursuant to Title 10 of the Code of Federal Regulations, Section 2.108, "Denial of application for failure to supply information."
-2 Please contact me at 301-415-2833, if you have any questions.
Sincerely,
~~
Peter Bamford, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289
Enclosure:
As stated cc: Distribution via Listserv
REQUEST FOR ADDITIONAL INFORMATION THREE MILE ISLAND NUCLEAR STATION, UNIT 1 PROPOSED RELOCATION OF SURVEILLANCE FREQUENCIES TO A LICENSEE CONTROLLED PROGRAM DOCKET NO. 50-289 By letter dated March 24, 2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML100840205), Exelon Generation Company, LLC (Exelon, the licensee), submitted a license amendment request (LAR) for Three Mile Island Nuclear Station, Unit 1 (TMI-1). The licensee proposes to modify the TMI-1 Technical Specifications (TSs) by relocating certain surveillance frequencies to a licensee-controlled program through the implementation of Nuclear Energy Institute (NEI) 04-10, "Risk-Informed Technical Specifications Initiative 5b, Risk-Informed Method for Control of Surveillance Frequencies." According to the licensee, the changes are consistent with U.S. Nuclear Regulatory Commission (NRC)-approved Technical Specifications Task Force (TSTF) Standard Technical Specifications (STSs) change TSTF-425, "Relocate Surveillance Frequencies to Licensee Control- Risk Informed Technical Specifications Task Force Initiative 5b," Revision 3. In order for the NRC staff to complete its review of the LAR, a response to the following request for additional information (RAI) is requested.
RAI-1
The LAR states that the changes presented are consistent with TSTF-425 and also includes a discussion of the differences in the application that result primarily from the custom TMI-1 TSs as compared to the STSs presented in TSTF-425 and NUREG-1430.
The LAR, Attachment 4, "TSTF-425 (NUREG-1430) vs. TMI Unit 1 Cross-Reference," is provided to aid in the determination of consistency of the surveillances proposed for relocation as compared to TSTF-425. In order to verify that the surveillances proposed for relocation are consistent with TSTF-425 as the LAR asserts, the NRC staff requests that the licensee provide corresponding TSTF-425 cross references for the following surveillance frequencies proposed for relocation: Table 4.1-1, "Instrument Surveillance Requirements," Channel Description Nos. 11, 15, 17, 1ge, 19f, 45, and 46.
RAI-2
With reference to the LAR, Attachment 2, Table 2-1, each of the findings in the following table identified an issue or gap that, individually, might not significantly impact the results from a surveillance test interval (STI) risk evaluation performed via the NEI 04-10 methodology, but, when taken cumulatively, could prove significant. The NRC staffs comment associated with each is highlighted in italics. Please address whether, when taken cumulatively, their effects could prove significant to the risk evaluation for an STI TS change and, if not, why not.
Enclosure
- 2 Peer Review IssuelGap Finding IE-A4a-01 "The potential for common cause failures [CCFs] was included in examination of potential initiating events resulting from the systematic evaluation for potential initiating events." As recommended per [Regulatory Guide] RG 1.200, Rev. 2, for Supporting Requirement (SR) IE-A6 (Capability Category [(CC)]-II),
this examination should also include CCFs from routine system alignments that could result from preventive and corrective maintenance.
IE-A5-01 "No documentation was found of incorporating: (a) events that have occurred at conditions other than at-power operation (Le., during low-power or shutdown conditions), and for which it is determined that the event could also occur during at-power operation; (b) events resulting in a controlled shutdown that includes a scram prior to reaching low-power conditions, unless it is determined that an event is not applicable to at-power operation." SR IE-A 7 requires that, even if not documented, these events have to be incorporated.
IE-A6-01 "No documentation was found of interviews with plant personnel and (e.g., operations, maintenance, engineering, safety analysis) to IE-A7-01 determine if potential initiating events have been overlooked ... No documentation of the review of plant-specific operating experience for initiating event precursors was found in the [probabilistic risk assessment] PRA notebooks." Even if not documented, CC-II for both of these SRs requires that the interviews (SR IE-A8 [CC-II],
with finding IE-A6-01) and reviews (SR IE-A9 [CC-II], with finding IE A7-0t) have been conducted.
SC-C2-01 SR SC-C2 requires that, even if not documented (or else still in the process of being documented), computer code "limitations or potential conservatisms" have to be addressed.
QU-D5-01 "Some SSCs [structures, systems, and components] that are significant contributors to initiating events, but not to mitigation, are not explicitly identified in the documentation of significant contributors." CC-II for SR QU-D6, against which this finding is cited, requires that significant contributors to core damage frequency, including initiating events, and SSCs and operator actions that contribute to initiating event frequencies, be identified.
While "not explicitly identified" in the documentation, were these significant contributors to initiating events actually identified but just omitted from the documentation? If they were not identified, how were they known to be significant and to what extent?
QU-F5-01 "[O]ther than the [large early release frequency] LERF truncation limitation, no evaluations of limitations were presented ..., [including]
limitations of the model as they may apply to applications." As implied by SR QU-F5, these limitations need to have been addressed.
- 3 Peer Review IssuelGap Finding LE-C8a-01 "The Reactor Building fan coolers are undersized at TMI and have a little to no impact on containment [CNMT] pressure and temperature with respect to early containment failure." SR LE-C9 (CC-II) requires justification for any credit taken for equipment survivability under adverse environmental conditions such that, even if the fan coolers were assumed to be failed, there would be "little to no impact" on CNMT pressure and temperature with respect to early CNMT failure.
LE-E4-01 "The level 2 results with the flag file are expected to be conservative.
When the cutsets were reviewed, it was determined that there appears to be non-minimal cutsets in the level 2 model as quantified without the flag file ... Some sensitivities have been performed, although a conclusive determination has not been made regarding the current method for quantifying LERF ... ([T]he TMI model uses Forte 3.0c as the quantifier)." SR LE-E4 requires that LERF be quantified consistently as with core damage frequency. This implies that the LERF quantification be conclusively determined as conservative, e.g., by quantifying LERF using Forte 3.0c at a greater truncation value just to assess whether the use of the flag file produces conservative results.
RAI-3
With reference to the LAR, Attachment 2, Table 2-2, Finding DA-B2-01 states: "There is no evidence that the intent of this SR was met. Although the component failure rates are grouped by system and component type, that does not guarantee that outliers are not included in a group." SR DA-B2 (CC-II) requires exclusion of outliers in the definition of systemlcomponent failure groups. Were outliers appropriately excluded from group definitions? If not, will their exclusion be part of the sensitivity analysis for an STI evaluation?
RAI-4
With reference to the LAR, Attachment 2, Table 2-2, Finding IFEV-A5-01 states: "Several requirements in establishing Hood initiating event frequencies are not met." Specifically cited are SRs IFEV-A5 through IFEV-A7, which require inclusion of plant-specific information and consideration of human-induced floods during maintenance (CC-II). Are any of the valves that may be assigned new STls potential flooding sources, such that increasing the STI could increase the frequency of a flood due to miscalibration, etc., of one of these valves?
-2 Please contact me at 301-415-2833, if you have any questions.
Sincerely,
/raJ Peter Bamford, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289
Enclosure:
As stated cc: Distribution via Listserv DISTRIBUTION:
RidsNrrPMThreeMilelsland Resource PUBLIC LPLI-2 R/F RidsAcrsAcnw_MailCTR Resource RidsNrrDraApla Resource RidsOgcRp Resource RidsRgn1 MailCenter Resource RidsNrrDorlDpr Resource RidsNrrDorlLpl1-2 Resouce RidsNrrLAABaxter Resource RGalJucci, NRR ADAMS Accession Number' ML101680647 "concurrence via memo OFFICE LPL 1-2/PM LPL1-2/LA AADB/BC LPLI-2/BC NAME PBamford ABaxter DHarrison* HChernoff DATE 6/24/10 7/1/10 05102/2010 7/2/10 OFFICIAL RECORD COPY