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Category:E-Mail
MONTHYEARML23348A3472023-12-12012 December 2023 NRR E-mail Capture - (External_Sender) NRC Notification to the State of Minnesota Regarding a Prairie Island Nuclear Generating Plant, Units 1 & 2, Amendment ML23335A1152023-12-0101 December 2023 NRR E-mail Capture - Prairie Island Units 1 and 2 - Request for Additional Information LAR to Revise TS 3.7.8 Required Actions ML23312A0882023-11-0808 November 2023 Acceptance of Request to Revise Alternatives 1-RR-5-10 and 2-RR-5-10 ML23248A3462023-09-0505 September 2023 NRR E-mail Capture - Request for Additional Information for Monticello Nuclear Generating Plant and Prairie Island Nuclear Generating Plant - Decommissioning Funding Status Reports ML23207A1962023-07-26026 July 2023 NRR E-mail Capture - Prairie Island Units 1 and 2 - Acceptance of Requested Licensing Action Request to Revise Technical Specification 3.7.8 Required Actions ML23075A2802023-03-16016 March 2023 NRR E-mail Capture - Prairie Island Units 1 and 2 - Acceptance of Relief Requests 1-RR-5-15 and 2-RR-5-15 to Use Subsequent ASME Code Edition and Addenda ML23065A0592023-02-27027 February 2023 NRR E-mail Capture - (External_Sender) Prairie Island Request for Pre-application Meeting for Proposed LAR to Change TS 3.7.8, Condition B Required Actions ML23018A2952023-01-18018 January 2023 Acceptance of Requested Licensing Action to Revise Technical Specification 5.6.6, Reactor Coolant System (RCS) Pressure and Temperature Limits Report (PTLR) (EPID L-2022-LLA-0184) (Email) ML22167A0452022-06-16016 June 2022 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Request to Adopt TSTF-277 ML22166A4112022-06-15015 June 2022 NRR E-mail Capture - Request for Additional Information Prairie Island Nuclear Generating Plant, Unit 2, Alternative RR-08, PIV Leakage ML22160A6022022-06-0909 June 2022 NRR E-mail Capture - Draft Request for Additional Information Prairie Island Nuclear Generating Plant, Units 1 and 2, 24-Month Operating Cycle Amendment ML22131A2652022-05-11011 May 2022 NRR E-mail Capture - Request for Additional Information Xcel Energy Amendment Request to Create a Common Eplan and EOF for Monticello and Prairie Island ML22045A4972022-02-14014 February 2022 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Unit 2 - Acceptance of Alternative Request Alternative Related PIV Leakage Monitoring ML21347A0082021-12-10010 December 2021 NRR E-mail Capture - Monticello and Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested License Amendment Standard Emergency Plan and Consolidated Emergency Operations Facility ML21321A0452021-11-10010 November 2021 Request for Additional Information: Prairie Island 24-Month Cycle Amendment Request ML21302A1252021-10-29029 October 2021 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action RTS Power Range Amendment ML21305A0102021-10-29029 October 2021 NRR E-mail Capture - Request for Additional Information Prairie Island Cooling Water Amendment ML21252A0152021-09-0202 September 2021 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Change in the Maximum Surveillance Intervals from 24 Months to 30 Months ML21252A0122021-08-30030 August 2021 NRR E-mail Capture - Request for Additional Information Amendment Request to Adopt TSTF-471 and 517-T for Prairie Island ML21133A2502021-05-13013 May 2021 NRR E-mail Capture - Prairie Island - Acceptance Review of TSTF-471 and TSTF-571-T ML20343A1292020-12-0808 December 2020 NRR E-mail Capture - Request for Additional Information ML20253A2782020-09-0909 September 2020 E-Mail Submitting Proposed New License Condition ML20254A1162020-09-0909 September 2020 Draft License Transmittal E-Mail ML20223A0632020-08-10010 August 2020 Email Shpo Comment Letter: Proposed License Amendment for the Prairie Island Independent Spent Fuel Storage Installation ML20192A1442020-07-0707 July 2020 NRR E-mail Capture - Request for Additional Information Prairie Island License Amendment Request to Adopt TSTF-505 ML20163A4282020-06-10010 June 2020 Email from MPCA Comment Letter - Prairie Island ISFSI ML20154K7632020-06-0202 June 2020 NRR E-mail Capture - Revision 2 to the Plan for the Audit of the Prairie Island Nuclear Generating Plant TSTF-505 License Amendment Request (Epdi: L-2019-LLA-0283) ML20135G8212020-05-14014 May 2020 NRR E-mail Capture - Revision to the Plan for the Audit of the Prairie Island Nuclear Generating Plant TSTF-505 License Amendment Request (Epdi: L-2019-LLA-0283) ML20112F4582020-04-21021 April 2020 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Low Temperature Overpressure Protection ML20083F4202020-03-20020 March 2020 NRR E-mail Capture - Plan for the Audit of the Prairie Island Nuclear Generating Plant TSTF-505 License Amendment Request (Epdi: L-2019-LLA-0283) ML20077L4632020-03-17017 March 2020 NRR E-mail Capture - Monticello Nuclear Generating Plant and Prairie Island Nuclear Generating Plant, Units 1 and 2 -Acceptance of Requested Licensing Action Request to Adopt TSTF-529 ML20052C7582020-02-21021 February 2020 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Westinghouse NSAL-09-05 and NSAL-09-05 ML20035F1552020-02-0404 February 2020 NRR E-mail Capture - Request for Additional Information Monticello and Prairie Island Alternative Requests to Adopt Code Cases N-786-3 and N-789-3 (Epids: L-2019-LLR-0078 and L-2019-LLR-0079) ML20022A1762020-01-22022 January 2020 NRR E-mail Capture - Prairie Units 1 and 2 - Acceptance of Requested Licensing Action Application to Revise Technical Specifications to Adopt TSTF-547, Clarification of Rod Position Requirements ML20021A1832020-01-21021 January 2020 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2 ML19316A0172019-11-0101 November 2019 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Integrated Leak Rate Test Extension Request ML19253B9642019-09-10010 September 2019 NRR E-mail Capture - Monticello Nuclear Generating Plant and Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Relief Request Adoption of Code Case N-786-3 ML19233A0032019-08-14014 August 2019 NRR E-mail Capture - Request for Additional Information Prairie Island Relief Requests 1-RR-10 and 2-RR-10 ML19193A0142019-07-0909 July 2019 NRR E-mail Capture - Acceptance of Prairie Island Nuclear Generating Plant, Units 1 and 2 Relief Request Nos. 1-RR-5-10 and 2-RR-5-10 Related to Reactor Vessel Inspection Intervals) ML19057A1652019-02-26026 February 2019 NRR E-mail Capture - Request for Additional Information Prairie Island 50.69 Amendment Request ML19057A4212019-02-26026 February 2019 NRR E-mail Capture - Acceptance of Prairie Island Reactor Vessel Capsule Removal Schedule Request ML19008A3562019-01-0707 January 2019 NRR E-mail Capture - Prairie Island Nuclear Generating Plant - Audit Plan Related to the License Amendment Request to Implement 10 CFR 50.69 ML18351A0142018-12-14014 December 2018 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Classification of Certain Fuel Handling Equipment ML18347A3282018-12-12012 December 2018 E-Mail from M. Krick/Sses SSES ISFSI (Conversation Held on December 12, 2018) ML18313A0832018-11-0707 November 2018 NRR E-mail Capture - Request for Additional Information Prairie Island NFPA-805 License Condition Modification Amendment Request ML18235A2982018-08-23023 August 2018 NRR E-mail Capture - Request for Additional Information Prairie Island TSTF-425 License Amendment Request ML18233A3692018-08-21021 August 2018 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Adoption of 10 CFR 50.69 ML18201A4132018-07-20020 July 2018 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Amendment to Adopt TSTF-439 ML18159A3052018-06-0808 June 2018 NRR E-mail Capture - Monticello - Acceptance of Requested Relief Request RR-012: Lnservice Inspection Impracticality in Accordance with 10 CFR 50.55a(g)(5)(iii) During the Fifth Ten-Year Interval ML18113A2252018-04-23023 April 2018 NRR E-mail Capture - Prairie Island Nuclear Generating Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Amendment to Adopt TSTF-425 2023-09-05
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1NRR-PMDAPEm ResourceFrom:Kuntz, RobertSent:Tuesday, July 26, 2016 2:49 PMTo:Hazelhoff, Amy (Amy.Hazelhoff@xenuclear.com)Cc:Eckholt, Gene F.; Robinson, JaySubject:Prairie Island Nuclear Generating Plant - Requests for Additional Information re: LAR to Adopt NFPA 805 (CAC Nos. ME9734 and ME9735)Ms. Hazelhoff, By letter dated September 28, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12278A405), Northern States Power Company, a Minnesota corporation (NSPM, the licensee), doing business as Xcel Energy, submitted a license amendment request (LAR) to transition its fire protection licensing basis at the Prairie Island Nuclear Generating Plant (PINGP), Units 1 and 2, from paragraph 50.48(b) of Title 10 of the Code of Federal Regulations (10 CFR) to 10 CFR 50.48(c), National Fire Protection Association Standard NFPA 805 (NFPA 805). Supplemental information has been requested by the NRC staff and provided NSPM. The latest supplemental information was provided by NSPM in letter dated May 24, 2016 (Accession No. ML16152A046). Enclosure 1 to the letter provides NSPM's response to PRA RAI 03, including the response to PRA RAI 01.h. Enclosure 2 provides licensee identified LAR changes. Enclosure 3 provides an updated LAR
Attachment
M, License Condition Changes. Enclosure 4 provides an updated LAR Attachment S, Plant Modifications and Items for Implementation. Enclosure 5 provides an updated LAR Attachment W, Fire PRA Insights. The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the May 24, 2016, letter and determined that additional information is required to complete its technical review.
A requests for additional information (RAI) is provided below. As discussed, the staff requests a response to the RAI by August 19, 2016.
If you have any comments or questions on this request let me know.
Rob Kuntz Senior Project Manager US Nuclear Regulatory Commission (301) 415-3733 PRA RAI 01.h.01 The response to PRA RAI 01.h demonstrated through a sensitivity analysis that the total plant-level core damage frequency (CDF) for PINGP, Units 1 and 2, as well as the total delta () CDF for PINGP, Unit 1 exceed RG 1.174, Revision 2, "An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant Specific Changes to the Licensing Basis" (ADAMS Accession No. ML100910006), risk acceptance guidelines should the generic fire ignition frequencies be based upon those in Table 6-1 of NUREG-CR-6850, "EPRI/NRC-RES Fire PRA [FPRA] Methodology for Nuclear Power Facilities, Volume 2: Detailed Methodology." However, inconsistent with accepted guidance in Chapter 10 of NUREG/CR-6850, Supplement 1, "Fire Probabilistic Risk Assessment Methods Enhancements," the response did not describe fire protection, or related, measures that can be taken to provide additional defense-in-depth (DID); rather, the response only indicated that DID was already evaluated as part of the fire risk evaluations (FREs) for each fire area. Moreover, while the response identified the general conservatisms in the analysis, it did not discuss the risk significance of these conservatisms for those fire scenarios or areas most impacted by the sensitivity analysis. Therefore, as originally requested in PRA RAI 01.h, and commensurate with any potential increase in 2risk significance associated with use of generic fire ignition frequencies based upon those in Table 6-1 of NUREG/CR-6850, provide the following: (1) describe the fire protection, or related, measures that will be taken to provide additional DID, and (2) discuss relevant conservatisms in the analyses for those scenarios most impacted by the sensitivity studies and the risk significance of those conservatisms. PRA RAI 20 The discussion provided under Item 14 of Licensee-Identified Issue 5, included in Enclosure 2 to the letter dated May 24, 2016 (see page 68 of 74 of Enclosure 2), explains that the scope of modifications described in LAR Attachment S, Table S-2, Modification Item S2-10 has been reduced. As a result, the FPRA appears to have been updated to explicitly model the risk of the resulting breaker coordination and cable protection vulnerabilities and associated variance from deterministic requirements (VFDRs). Item 22 of Licensee-Identified Issue 5 (see page 70 of 74) discusses similar issues. In particular to circuit overcurrent protection inadequacies, the letter discusses that they are associated with fire damage to external direct current (DC) control cables that support overcurrent protection for medium voltage (4.16KV) switchgear breakers. While Items 14 and 22 of Licensee-Identified Issue 5 provide some discussion of how these inadequacies are modeled in the FPRA, this discussion is limited and does not provide sufficient detail for the NRC staff to complete its review. Provide the following information: a) Explain how inadequate coordination and overcurrent protection was modeled in the FPRA, and justify that this treatment addresses the failures that could occur as a result of the identified circuit inadequacies. b) Include a description of the circuit failure modes addressed and how associated component failures were modeled in the FPRA. Also, describe and justify assumptions made in the FPRA about how fire-induced faults associated with inadequately coordinated/protected circuits impact upstream and downstream components from the fault. c) Given the lack of electrical coordination and cable protection as a result of the reduced scope of modifications discussed in Items 14 and 22 of Licensee-Identified Issue 5, include an explanation of how the potential for secondary fires was addressed in the FPRA. If secondary fires were not modeled and fire-induced faults in inadequately protected circuits could lead to secondary fires, then justify this modeling exclusion. d) In line with the issues described above, the NRC staff also notes that a risk-informed (RI) approach was used in association with a reduction in scope of circuit-protection-related modifications (e.g., Item S2-10 of LAR Attachment S, Table S-2) by modeling overcurrent failure modes and secondary fires. These modifications would have provided overcurrent trip protection for certain circuits. As a result, i. Describe how the plant response model addresses fire-induced faulting of one or more load circuits at the same time that DC control power has been lost due to fire damage. ii. Explain how the lack of circuit protection and the resulting potential for common enclosure issues are analyzed. iii. Discuss the potential for secondary fires and describe how secondary fires are modeled (e.g., fire size, zone of influence, propagation, etc.). iv. Discuss the potential for high energy arcing faults to be created as a result of the inability to clear fire-induced load faults at the load breaker, and describe how such faults are modeled (fault location, zone of influence, fire propagation, etc.). Without DC control power being available at the switchgear, circuit breakers upstream may have to clear the fault and those 3breakers will very likely have a much higher overcurrent setpoint than that required to protect the integrity of the cables being faulted.
Hearing Identifier: NRR_PMDA Email Number: 2958 Mail Envelope Properties (Robert.Kuntz@nrc.gov20160726144800)
Subject:
Prairie Island Nuclear Generating Plant - Requests for Additional Information re: LAR to Adopt NFPA 805 (CAC Nos. ME9734 and ME9735) Sent Date: 7/26/2016 2:48:49 PM Received Date: 7/26/2016 2:48:00 PM From: Kuntz, Robert Created By: Robert.Kuntz@nrc.gov Recipients: "Eckholt, Gene F." <Eugene.Eckholt@xenuclear.com> Tracking Status: None "Robinson, Jay" <Jay.Robinson@nrc.gov> Tracking Status: None "Hazelhoff, Amy (Amy.Hazelhoff@xenuclear.com)" <Amy.Hazelhoff@xenuclear.com> Tracking Status: None Post Office: Files Size Date & Time MESSAGE 6981 7/26/2016 2:48:00 PM Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date: Recipients Received: