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MONTHYEARML12207A6012012-07-23023 July 2012 G20120539/EDATS: OEDO-2012-0449 - Incoming J. Sam Armijo Ltr. Final Safety Evaluation Report Associated with the Florida Power and Light St. Lucie, Unit 2, License Amendment Request for an Extend Power Uprate Project stage: Approval ML12207A4652012-08-10010 August 2012 G20120539/EDATS: OEDO-2012-0449 - Final Safety Evaluation Report Associated with the Florida Power and Light, St. Lucie Unit 2 Plant, License Amendment Request for an Extended Power Uprate Project stage: Approval 2012-07-23
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Category:E-Mail
MONTHYEARML24254A2562024-09-0606 September 2024 NRR E-mail Capture - (External_Sender) Psl Monthly Turtle Report for August 2024 ML24248A2422024-09-0404 September 2024 Acceptance Review for St. Lucie, Unit 2 - Relief Request (RR) 14: Limited Coverage Exams Due to Impractical Inservice Inspection Requirements - Fourth Ten-Year Inservice Inspection Program Interval ML24246A0152024-08-12012 August 2024 NRR E-mail Capture - (External_Sender) Psl Monthly Turtle Report for July 2024 ML24194A1222024-07-11011 July 2024 NRR E-mail Capture - (External_Sender) Psl Monthly Turtle Report for June 2024 ML24192A2302024-07-10010 July 2024 003 Radiation Safety Baseline Inspection Information Request ML24176A1612024-06-15015 June 2024 NRR E-mail Capture - (External_Sender) May 2024 FPL Marine Turtle Removal Monthly Report ML24150A2192024-05-29029 May 2024 (E-Mail) St. Lucie, Unit 2 - License Amendment Request, Updated Spent Fuel Pool Criticality Analysis - Acceptance Review ML24149A3532024-05-24024 May 2024 Change in Estimated Review Schedule for Nextera Common Emergency Plan Amendment ML24134A0142024-05-10010 May 2024 NRR E-mail Capture - (External_Sender) Pasl Monthly Turtle Report for April 2024 ML24122C6922024-05-0101 May 2024 NextEra Fleet EP Amendment - Demonstration Drill ML24113A0372024-04-22022 April 2024 NRR E-mail Capture - Acceptance Review - Turkey Point 3 and 4 and St. Lucie 2 - Request to Use Later Code of ASME (L-2024-LLR-0024) ML24101A2202024-04-0808 April 2024 NRR E-mail Capture - (External_Sender) Psl Monthly Turtle Report for March 2024 ML24074A4262024-03-12012 March 2024 NRR E-mail Capture - (External_Sender) Psl Monthly Turtle Report for February 2024 ML24177A2512024-02-12012 February 2024 Acceptance Review for RR 7-Proposed Alternative - Extension of Inspection Interval for St. Lucie Unit 1 Reactor Pressure Vessel Welds from 10 to 20 Years ML24036A2152024-02-0505 February 2024 NRR E-mail Capture - (External_Sender) Psl Monthly Turtle Report for January 2024 ML24031A5472024-01-13013 January 2024 NRR E-mail Capture - (External_Sender) December 2023 FPL Marine Turtle Removal Monthly Report ML24002A7272023-12-16016 December 2023 NRR E-mail Capture - (External_Sender) November 2023 FPL Marine Turtle Removal Monthly Report ML23332A0352023-11-27027 November 2023 Conversion to Improved Technical Specifications Change in Estimated Review Schedule ML23326A0252023-11-20020 November 2023 NRR E-mail Capture - (External_Sender) October 2023 FPL Marine Turtle Removal Monthly Report ML24008A1582023-11-14014 November 2023 NRR E-mail Capture - (External_Sender) Psl Monthly Turtle Report for October 2023 ML23254A2852023-09-11011 September 2023 NRR E-mail Capture - (External_Sender) August 2023 FPL Marine Turtle Removal Monthly Report ML23243A9862023-08-31031 August 2023 NRR E-mail Capture - Draft RAIs for EP Staff Augmentation Times LAR (L-2022-LLA-0166) ML23243A9182023-08-31031 August 2023 NRR E-mail Capture - Re Audit Plan - St. Lucie ITS Conversion LAR - Setpoints ML23228A1482023-08-16016 August 2023 NRR E-mail Capture - Acceptance Review Results - St. Lucie Nuclear Plant, Unit 2 Alternative PSL2-I5-RR-01 (L-2023-LLR-0038) ML23226A0762023-08-14014 August 2023 NRR E-mail Capture - Request for Additional Information - St. Lucie Plant, Units 1 and 2 - Adopt 10 CFR 50.69 (L-2022-LLA-0182) ML23226A0692023-08-12012 August 2023 NRR E-mail Capture - (External_Sender) July 2023 FPL Marine Turtle Removal Monthly Report ML23223A0152023-08-11011 August 2023 NRR E-mail Capture - Acceptance Review Results - St. Lucie Nuclear Plant, Unit 2 Alternative PR-10 (L-2023-LLR-0039) ML23191A1952023-07-10010 July 2023 NRR E-mail Capture - (External_Sender) June 2023 FPL Marine Turtle Removal Monthly Report ML23216A1412023-06-30030 June 2023 August 2023 RP Inspection Document Request ML23248A1292023-06-29029 June 2023 NRR E-mail Capture - St Lucie 50.69 - Additional Audit Questions ML23173A1522023-06-22022 June 2023 Request for Additional Information NextEra Fleet Emergency Plan Amendment Request ML23198A0662023-06-22022 June 2023 NRR E-mail Capture - (External_Sender) Green Turtle Nest on Canal Bank, June 2023 ML23198A0642023-06-12012 June 2023 NRR E-mail Capture - (External_Sender) Loggerhead Nest on Canal Bank, May 2023 ML23163A1732023-06-10010 June 2023 NRR E-mail Capture - (External_Sender) May 2023 FPL Marine Turtle Removal Monthly Report ML23163A1222023-05-30030 May 2023 NRR E-mail Capture - (External_Sender) Nest on Intake Canal Bank ML23138A0212023-05-17017 May 2023 Telephone Record, Call with Florida Power and Light Regarding Decommissioning Funding Plan Update Dated March 30, 2021 ML23137A0942023-05-17017 May 2023 NRR E-mail Capture - Audit Plan - St Lucie Plant, Units 1 and 2 - 10 CFR 50.69 LAR ML23135A0292023-05-12012 May 2023 NRR E-mail Capture - (External_Sender) April 2023 FPL Marine Turtle Removal Monthly Report ML23129A8312023-05-0808 May 2023 NRR E-mail Capture - Audit Plan - St. Lucie ITS Conversion LAR - Setpoints ML23109A1862023-04-19019 April 2023 and Turkey Point Acceptance of Requested Licensing Action Proposed Alternative to Asme Section XI Authorizing Implementation of Asme Code Case N-752-1 ML23198A1592023-04-0707 April 2023 NRR E-mail Capture - (External_Sender) March 2023 FPL Marine Turtle Removal Monthly Report ML23074A2292023-03-15015 March 2023 NRR E-mail Capture - (External_Sender) February 2023 FPL Marine Turtle Removal Monthly Report ML23041A2262023-02-10010 February 2023 NRR E-mail Capture - (External_Sender) January 2023 FPL Marine Turtle Removal Monthly Report ML23065A1142023-02-0101 February 2023 NRR E-mail Capture - (External_Sender) FPL St. Lucie Plant Biological Opinion SERO-2019-03494 - Submittal ML23254A4022023-01-24024 January 2023 RP Inspection_2023-001_Document Request ML23019A0142023-01-18018 January 2023 NRR E-mail Capture - (External_Sender) Regarding St. Lucie Olive Ridley Capture 1/3/2023 ML23006A1822023-01-0606 January 2023 NRR E-mail Capture - (External_Sender) Psl Smalltooth Sawfish Capture 1/5/23 ML23006A1882023-01-0606 January 2023 NRR E-mail Capture - (External_Sender) December 2022 FPL Marine Turtle Removal Monthly Report ML23006A0242023-01-0505 January 2023 NRR E-mail Capture - (External_Sender) Psl Olive Ridley Capture 1323 ML23019A2052022-12-24024 December 2022 Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors - Acceptance Review 2024-09-06
[Table view] Category:Final Safety Evaluation Report (FSER)
MONTHYEARML12207A6012012-07-23023 July 2012 G20120539/EDATS: OEDO-2012-0449 - Incoming J. Sam Armijo Ltr. Final Safety Evaluation Report Associated with the Florida Power and Light St. Lucie, Unit 2, License Amendment Request for an Extend Power Uprate 2012-07-23
[Table view] Category:Letter
MONTHYEARML24255A3092024-09-30030 September 2024 SLRA - Revised SE Letter L-2024-158, Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-09-25025 September 2024 Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes IR 05000335/20240112024-09-18018 September 2024 Biennial Problem Identification and Resolution Inspection Report 05000335/2024011 and 05000389/2024011 L-2024-136, Supplement to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-09-16016 September 2024 Supplement to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes L-2024-138, License Amendment Request L-2024-138, Fuel Methodology Changes in Support of St. Lucie, Unit 2 Transition to 24-Month Fuel Cycles2024-09-11011 September 2024 License Amendment Request L-2024-138, Fuel Methodology Changes in Support of St. Lucie, Unit 2 Transition to 24-Month Fuel Cycles L-2024-148, Submittal of Offsite Dose Calculation Manual (Odcm), Revision 552024-09-0909 September 2024 Submittal of Offsite Dose Calculation Manual (Odcm), Revision 55 IR 05000335/20240052024-08-22022 August 2024 Updated Inspection Plan for St. Lucie, Units 1 & 2 - Report 05000335/2024005 and 05000389/2024005 L-2024-140, Cycle 28 Core Operating Limits Report2024-08-14014 August 2024 Cycle 28 Core Operating Limits Report L-2024-133, Snubber Program Plan Submittal2024-08-14014 August 2024 Snubber Program Plan Submittal L-2024-132, 2024 Population Update Analysis2024-08-13013 August 2024 2024 Population Update Analysis IR 05000335/20240022024-08-13013 August 2024 Integrated Inspection Report 05000335-2024002 and 05000389-2024002 L-2024-129, Relief Request (RR) 14. Limited Coverage Exams Due to Impractical Inservice Inspection Requirements - Fourth Ten-Year Inservice Inspection Program Interval2024-08-0707 August 2024 Relief Request (RR) 14. Limited Coverage Exams Due to Impractical Inservice Inspection Requirements - Fourth Ten-Year Inservice Inspection Program Interval ML24163A0012024-08-0505 August 2024 LTR-24-0119-1-1 Response to Nh Letter Regarding Review of NextEras Emergency Preparedness Amendment Review 05000389/LER-2024-003, Unplanned Reactor Scram2024-08-0505 August 2024 Unplanned Reactor Scram L-2024-121, Subsequent License Renewal Commitment 30 Revision2024-07-30030 July 2024 Subsequent License Renewal Commitment 30 Revision L-2024-123, Submittal of In-Service Inspection Program Owners Activity Report (OAR-1)2024-07-29029 July 2024 Submittal of In-Service Inspection Program Owners Activity Report (OAR-1) L-2024-125, Notice of Intent to Provide Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-07-24024 July 2024 Notice of Intent to Provide Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes ML24184B2822024-07-16016 July 2024 – Request to Use a Later Code Edition and Addenda of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI ML24193A2432024-07-12012 July 2024 – Interim Audit Summary Report in Support of Review of License Amendment Requests Regarding Fleet Emergency Plan L-2024-117, Safety Injection Tank Vent Through Wall Leakage2024-07-11011 July 2024 Safety Injection Tank Vent Through Wall Leakage L-2024-110, Environmental Protection Plan Report, Unusual or Important Environmental Event - Manatee in Intake2024-07-10010 July 2024 Environmental Protection Plan Report, Unusual or Important Environmental Event - Manatee in Intake L-2024-114, Quality Assurance Topical Report (FPL-1 Revision 31 Annual Submittal2024-07-10010 July 2024 Quality Assurance Topical Report (FPL-1 Revision 31 Annual Submittal L-2024-109, Schedule for Subsequent License Renewal Environmental Review2024-07-0303 July 2024 Schedule for Subsequent License Renewal Environmental Review ML24172A1562024-06-27027 June 2024 Relief Request - PSL2-I5-RR-01 Proposed Alternative to Amse Code XI Code Examination Requirements - System Leakage Test of Reactor Pressure Vessel Bottom Head and Class 1 and 2 Piping in Covered Trenches L-2024-104, Response to Request for Additional Information, St. Luce Relief Request (RR) 7, Proposed Alternative in Accordance with 10 CFR 50.55a(z)(1 Extension of Inspection Interval for Reactor Pressure Vessel Welds from 102024-06-26026 June 2024 Response to Request for Additional Information, St. Luce Relief Request (RR) 7, Proposed Alternative in Accordance with 10 CFR 50.55a(z)(1 Extension of Inspection Interval for Reactor Pressure Vessel Welds from 10 L-2024-097, Technical Specification Special Report2024-06-20020 June 2024 Technical Specification Special Report L-2024-102, Official Service List Update2024-06-19019 June 2024 Official Service List Update ML24149A2862024-06-12012 June 2024 NextEra Fleet - Proposed Alternative Frr 23-01 to Use ASME Code Case N-752-1, Risk-Informed Categorization and Treatment for Repair/Replacement Activities in Class 2 and 3 Systems Section X1, Division 1 (EPID L-2023-LLR-0009) - Letter L-2024-090, Revised Steam Generator Tube Inspection Reports2024-06-0404 June 2024 Revised Steam Generator Tube Inspection Reports IR 05000335/20244012024-06-0303 June 2024 Security Baseline Inspection Report 05000335/2024401 and 05000389/2024401 ML24135A0642024-05-17017 May 2024 Correction Letter - Amendment Nos. 253 and 208 Regarding Conversion to Improved Standard Technical Specifications L-2024-075, Notification of Improved Standard Technical Specifications (ITS) Implementation2024-05-13013 May 2024 Notification of Improved Standard Technical Specifications (ITS) Implementation IR 05000335/20240012024-05-10010 May 2024 Integrated Inspection Report 05000335/2024001 and 05000389/2024001 ML24127A0632024-05-0606 May 2024 Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes L-2024-053, License Amendment Request L-2024-053, Updated Spent Fuel Pool Criticality Analysis2024-04-30030 April 2024 License Amendment Request L-2024-053, Updated Spent Fuel Pool Criticality Analysis L-2024-070, Cycle 32 Core Operating Limits Report2024-04-29029 April 2024 Cycle 32 Core Operating Limits Report L-2024-071, Cycle 27 Core Operating Limits Report2024-04-29029 April 2024 Cycle 27 Core Operating Limits Report ML24108A0632024-04-18018 April 2024 – Notification of Inspection and Request for Information for NRC Problem Identification and Resolution Inspection L-2024-056, Annual Radiological Environmental Operating Report for Calendar Year 20232024-04-17017 April 2024 Annual Radiological Environmental Operating Report for Calendar Year 2023 L-2024-064, Florida Power & Light Company - 10 CFR 50.46 - Emergency Core Cooling System SBLOCA 30-Day Report2024-04-17017 April 2024 Florida Power & Light Company - 10 CFR 50.46 - Emergency Core Cooling System SBLOCA 30-Day Report L-2024-054, 2023 Annual Environmental Operating Report2024-04-0909 April 2024 2023 Annual Environmental Operating Report ML24093A2612024-04-0202 April 2024 – Investigation Summary, Office of Investigations Case Number 2-2023-005 L-2024-047, Proposed Use of a Subsequent ASME Code Edition and Addenda2024-03-28028 March 2024 Proposed Use of a Subsequent ASME Code Edition and Addenda L-2024-045, Report of 10 CFR 72.48 Plant Changes2024-03-27027 March 2024 Report of 10 CFR 72.48 Plant Changes ML24078A2622024-03-26026 March 2024 Revision to the Reactor Vessel Material Surveillance Capsule Withdrawal Schedule ML24058A1572024-03-19019 March 2024 Exemption from Select Requirements of 10 CFR Part 73 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting) L-2024-011, and Point Beach, Units 1 and 2 - 10 CFR 50.46 Annual Reporting of Changes to, or Errors in Emergency Core Cooling System Models or Applications2024-03-13013 March 2024 and Point Beach, Units 1 and 2 - 10 CFR 50.46 Annual Reporting of Changes to, or Errors in Emergency Core Cooling System Models or Applications ML24017A2092024-03-12012 March 2024 – Issuance of Amendment Nos. 254 and 209 to Adopt 10 CFR 50.69, Risk Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors L-2024-023, Unusual or Important Environmental Event - Turtle Mortality2024-03-0606 March 2024 Unusual or Important Environmental Event - Turtle Mortality L-2024-027, Safety Injection Tank Vent Through Wall Leakage2024-02-29029 February 2024 Safety Injection Tank Vent Through Wall Leakage 2024-09-09
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EDO Principal Correspondence Control FROM: DUE: 08/23/12 EDO CONTROL: G20120539 DOC DT: 07/23/12 FINAL REPLY: J. Sam Armijo ACRS R.W. Borchardt, EDO FOR SIGNATURE OF :** GRN **CRC NO: EDO DESC: ROUTING: Final Safety Evaluation Report Associated with the Florida Power and Light St. Lucie, Unit 2, License Amendment Request for an Extend Power Uprate (EDATS: OEDO-2012-0449)
DATE: 07/25/12 Borchardt Weber Johnson Ash Mamish OGC/GC Merzke, OEDO Kotzalas, OEDO ASSIGNED TO: NRR CONTACT: Leeds SPECIAL INSTRUCTIONS OR REMARKS: Please prepare a response for the signature of the EDO. Add the Commission and SECY as cc's. Also, please add RidsAcrsAcnwMailCTR to your distribution on the concurrence page. USE SUBJECT LINE IN RESPONSE.OV~LA-T~ U-P-O-O(0 I Lno-o(
EDATS Number: OEDO-2012-0449 Source: OEDO Genra Ifomaio Assigned To: NRR OEDO Due Date: 8/23/2012 11:00 PM Other Assignees:
SECY Due Date: NONE
Subject:
Final Safety Evaluation Report Associated with the Florida Power and Light St. Lucie, Unit 2, License Amendment Request for an Extended Power Uprate
Description:
CC Routing: Merzke, Dan ADAMS Accession Numbers -Incoming:
NONE Response/Package:
NONE I~ OteInomto Cross Reference Number: G20120539 Related Task: File Routing: EDATS Staff Initiated:
NO Recurring Item: NO Agency Lesson Learned: NO OEDO Monthly Report Item: NO II Prcs Inomtn I Action Type: Letter Priority:
Medium Sensitivity:
None Signature Level: EDO Urgency: N Approval Level: No Approval Required OEDO Concurrence:
NO OCM Concurrence:
NO OCA Concurrence:
NO Special Instructions:
Please prepare a response for the signature of the EDO. Add the Commission and SECY as cc's.Also, include: RidsAcrsAcnwMaiICTR to your distribution on the concurrence page. USE SUBJECT LINE IN RESPONSE.0 jI Dou en Inoraio Originator Name: J. Sam Arm ijo Originating Organization:
ACRS Addressee:
R. W. Borchardt, EDO Incoming Task Received:
Letter Date of Incoming:
7/23/2012 Document Received by OEDO Date: 7/24/2012 Date Response Requested by Originator:
NONE Page 1 of I UNITED STATES NUCLEAR REGULATORY COMMISSION ADVISORY COMMITTEE ON REACTOR SAFEGUARDS WASHINGTON, DC 20555 -0001 July 23, 2012 Mr. R.W. Borchardt Executive Director for Operations U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
FINAL SAFETY EVALUATION REPORT ASSOCIATED WITH THE FLORIDA POWER AND LIGHT ST. LUCIE, UNIT 2, LICENSE AMENDMENT REQUEST FOR AN EXTENDED POWER UPRATE
Dear Mr. Borchardt:
During the 5 9 6 th meeting of the Advisory Committee on Reactor Safeguards, July 11-13, 2012, we completed our review of the license amendment request (LAR) for the extended power uprate (EPU) of St. Lucie, Unit 2, (St. Lucie 2) and the associated draft Safety Evaluation (SE).Our Subcommittee on Power Uprates reviewed this matter in a meeting on June 22, 2012.During these reviews, we met with representatives of the staff, Florida Power and Light Company (FPL or the licensee), and their consultants.
We did not review the St. Lucie 2 spent fuel pool analysis, which is still under review by the staff. We had the benefit of the documents referenced.
CONCLUSIONS AND RECOMMENDATION
- 1. The FPL LAR for an EPU of St. Lucie 2 should be approved subject to the conditions imposed in the staffs draft Safety Evaluation.
- 2. Fuel thermal conductivity degradation (TCD) phenomena at St. Lucie 2 are addressed by the license condition that FPL maintain more restrictive operational/design radial power fall-off (RFO) curve limits.3. The licensee's action plan addresses our concerns related to further wear of the tubes in the replacement steam generators (SGs).BACKGROUND The two unit St. Lucie Nuclear Power Plant is located on Hutchinson Island, near Ft. Pierce, Florida in St. Lucie County. Unit 2 is a 2x4 loop pressurized water reactor, designed by Combustion Engineering and licensed in 1983 to operate at 2560 MWt. In 1985, the unit was approved for a 5% stretch uprate to the currently licensed thermal power (CLTP) of 2700 MWt.In this LAR, FPL requested approval of a power uprate of 10% above the CLTP and a 1.7%measurement uncertainty recapture (MUR) to allow a maximum core power level of 3020 MWt.FPL plans to implement this EPU in the fall of 2012.EDO --G20120539 There are no changes in the reactor coolant system, reactor vessel internals, and fuel type due to the EPU. The two St. Lucie 2 SGs were replaced in 2007 with AREVA Model 86/19TI SGs.The reactor vessel closure head was replaced in 2007.The EPU will change some core design parameters including fuel enrichment and radial peaking factor, but the maximum linear heat rate will remain the same. The core average coolant temperature will increase from 573.3 0 F to 578.5 0 F. The reactor vessel head temperature will increase from about 595°F to 604 0 F. Design steam mass flow rates in each of the SGs will increase by approximately 13%.Safety-related changes include control room air conditioning, charging pump control circuits, neutron absorption materials in spent fuel pool storage racks, nuclear steam supply system setpoints, environmental qualification of electrical equipment, component cooling water supports, and the SG low-level trip setpoints.
Installation of a Leading Edge Flow Measurement system reduces flow measurement uncertainty and allows a 1.7% increase in power. Some of these changes have already been implemented, and the remaining changes will be completed during the fall 2012 outage.DISCUSSION We reviewed the staffs evaluation of the EPU effects on station blackout, component material degradation, risk, and electrical power systems. In addition, we considered the licensee's power ascension test program. Issues of special interest that arose during our review are discussed in this letter.Fuel Thermal Conductivity Degradation (TCD)NRC Information Notice 2009-23, "Nuclear Fuel Thermal Conductivity Degradation," describes an issue concerning the ability of legacy thermal-mechanical fuel modeling codes to accurately predict the exposure-dependent fuel TCD.The NRC-approved FATES3B fuel rod performance model used by FPL for predicting fuel centerline temperature at high burnup does not model TCD. In response to staff concerns, FPL proposed a license condition that will impose more restrictive operational/design radial power fall-off (RFO) curve limits for St. Lucie 2. The new RFO curve limits were derived by comparing FATES3B fuel temperature predictions to results from Halden fuel tests. FATES3B predictions compared well to Halden data up to intermediate levels of rod average burnup (about 35 GWd/MTU).
The predictions underestimate fuel centerline temperatures at higher burnups.New RFO curve limits were determined by imposing in the analysis a penalty that increases from 0-200°F over the burnup range from 35-50 GWd/MTU and remains constant for higher burnups. The staff compared FPL FATES3B fuel temperature predictions that incorporate this RFO curve penalty to Halden data and performed independent FRAPCON-3.4 calculations.
Based on these comparisons, the staff concluded that this was acceptable for addressing TCD phenomena at St. Lucie 2. The more restrictive RFO curve limits will be verified as part of the Reload Safety Analysis Checklist process. Steam Generator Performance Each replacement SG contains 8999 thermally-treated Alloy 690 tubes with broached stainless steel horizontal supports and an anti-vibration bar (AVB) system. The steam generator supplier, AREVA, performed design calculations with their codes to ensure that accumulated SG tube wear was acceptable for 110% CLTP and EPU conditions.
After their first 18 month cycle of operation at the CLTP level, an inspection revealed a number of tube-to-AVB wear indications (3700 indications on 1231 tubes in SG A and 2157 indications on 815 tubes in SG B). Approximately 90% of these wear indicators were less than 15% of the tube wall thickness.
Although none of the tube wear reached the 40% wear limit that would require plugging, FPL conservatively plugged the 14 tubes with greater than 25% wear (e.g., 8 tubes in SG A and 6 tubes in SG B). After their second 18 month cycle of operation, inspections found an additional 2164 indications on tubes in SG A and 804 additional indications on tubes in SG B (bringing the total number of affected tubes to 1862 for SG A and to 1125 for SG B). The measured average wear rates reduced from 7.9 to 4.0 %/EFPY for SG A and from 7.7 to 1.6%/EFPY for SG B, but one tube in SG A reached the 40% wear limit for plugging.
In addition, the licensee plugged any tubes with measured wear exceeding approximately 30% (a total of 16 additional tubes in SG A and 5 additional tubes in SG B).The licensee completed a root cause evaluation that considered factors such as SG design, manufacturing processes, materials and associated tolerances, and potential operational effects. They concluded that the root cause was that the U-tubes were not effectively supported during SG manufacture, which caused the tubes to sag into the AVBs and led to slight AVB deformation that closed the tube-to-AVB gap at specific locations.
This exacerbated tube wear in those locations.
Supporting information for this root cause evaluation included updated AREVA analyses with revised gap distributions that predict wear similar to observed values after the first and second inspections.
The licensee's analyses indicate that the increased steam flow rates associated with the EPU will have a negligible effect on the observed tube wear rates. Results from a third full 100%bobbin coil inspection (scheduled for this fall) will provide additional information.
In addition, a full 100% bobbin coil inspection will be conducted after EPU conditions are implemented.
The licensee performed an operational assessment for the next two cycles which included a cycle under EPU conditions.
This assessment was based on wear rate data from the first two inspections.
The analysis applied a factor of 1.24 to the wear rates to account for the increase in wear rate due to the change in flow conditions for the EPU. The factor of 1.24 is based on an analysis with the tube and support in contact in accordance with the root cause evaluation.
The assessment does not credit any additional attenuation of the wear rates that may occur during the current cycle of operation.
Assessment results indicate acceptable margin against tube structural integrity requirements, indicating a probability of loss of margin of 0.02 versus an allowable value of 0.05. The tube wear observed at St Lucie 2 is primarily at AVB supports.
This is different than the form of degradation reported to have occurred at San Onofre. There are a number of design differences between the SGs installed at San Onofre and those at St Lucie 2. We reviewed the FPL evaluation of these differences and concluded that the forms of degradation reported to have occurred at San Onofre are less likely to occur at St Lucie 2. This will be verified by the inspection following the first EPU cycle.These considerations and the licensee's action plan adequately address concerns about SG tube integrity.
CLOSING COMMENT In summary, the EPU license amendment request for St. Lucie 2 should be approved with the license conditions identified in the SER.Sincerely, IRAI J. Sam Armijo Chairman REFERENCES
- 1. License Amendment Request for Extended Power Uprate, St. Lucie, Unit 2, Docket No.50-389, Renewed License No. NPF-16, February 25, 2011, (ML110730116).
- 2. Draft NRC Safety Evaluation on St. Lucie 2 EPU, updated July 2012 (ML12145A032).
- 3. NRC Review Standard 001 (RS-001), "Review Standard for Extended Power Uprate," Revision 0, December 2003 (ML033640024).
- 4. CENPD-132, Supplement 4-P-A, Calculative Methods for the C-E Nuclear Power Large Break LOCA Evaluation Model, April 2001 (ML011030417).
- 5. NRC Information Notice 2009-23, "Nuclear Fuel Thermal Conductivity Degradation," October 8, 2009 (ML091550527).
- 6. CENPD-139-P-A, Fuel Evaluation Model, July 1974, (ML120960147).
- 7. CEN-161(B)-P-A, Improvements to Fuel Evaluation Model, August 1989, (MLI120960155).
- 8. CEN-161(B)-P, Supplement 1-P-A, Improvements to Fuel Evaluation Model, January 1992, (MLI120960175).
- 9. CENPD-275-P, Revision 1-P-A, C-E Methodology for Core Designs Containing Gadolinia-Urania Burnable Absorbers, May 1988. 10. CEN-372-P-A, Fuel Rod Maximum Allowable Gas Pressure, May 1990.11. CENPD-275-P, Revision 1-P, Supplement 1-P-A C-E Methodology for PWR Core Designs Containing Gadolinia-Urania Burnable Absorbers, April 1999.12. Letter from B. T. Moroney (NRC) to J. A. Stall (FP&L), St. Lucie Plant, Unit 2 -Issuance of Amendment Regarding Change in Reload Methodology and Increase in Steam Generator Tube Plugging Limit (TAC No. MC1 566), January 31, 2005 (ML050120363).
- 13. CENPD-404-P-A, Revision 0, Implementation of ZIRLOTM Cladding Material in CE Nuclear Power Fuel Assembly Designs, November 2001 (ML013270123 and 013270127).
- 14. CEN-386-P-A, Verification of the Acceptability of a 1-Pin Burnup Limit of 60 MWD/kgU for Combustion Engineering 16x16 PWR Fuel, ABB Combustion Engineering, Inc., August 1992.15. CENPD-384-P, Report on the Continued App!icability of 60 MWD/kgU for ABB Combustion Engineering PWR Fuel, ABB Combustion Engineering, Inc., September 1995.