ML18177A208
| ML18177A208 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 06/27/2018 |
| From: | DTE Energy |
| To: | Division of Operating Reactor Licensing |
| Green K J, 415-1627 | |
| References | |
| Download: ML18177A208 (18) | |
Text
Fermi Unit 2License Amendment Pre-submittal Meeting Neutron Absorbing InsertsJune 27, 2018 1
Agenda*ObjectivesKevin Lynn (DTE)*BackgroundKevin Lynn (DTE)*LAR OverviewKevin Lynn (DTE)*NETCO-SNAP-IN Rack InsertsMatt Harris (Curtiss-Wright)*Summary / Questions / FeedbackKevin Lynn (DTE)*Criticality Analysis (Closed Portion)
Chris Kmiec (GNF) 2Fermi 2 License Amendment Pre-Submittal Meeting Objectives*Provide the NRC with an overview of the proposed license amendment request (LAR):-Scope and content-Methodology
-Submittal schedule*Obtain NRC feedback-Content
-Approval schedule
-Lessons learned 3Fermi 2 License Amendment Pre-Submittal Meeting 4*Fermi 2 spent fuel pool (SFP) contains two types of storage racks: Boral (Holtec) and Boraflex(Joseph Oat)*During license renewal, a license condition was imposed that:
"DTE Electric Company shall fully implement the Boraflexrack replacement approved in Amendment No. 141 before the PEO (i.e., March 20, 2025), so that the Boraflexmaterial in the spent fuel pool will not be required to perform a neutron absorption function. DTE Electric Company shall submit a letter to the NRC, within 60 days following completion of the removal of the Boraflexmaterial and installation of the Boral material, as described in Amendment No. 141, confirming the removal of the Boraflexmaterial and discontinued reliance on its neutron absorption function."*As an alternative to implementing the previously approved amendment to replace the Boraflexracks with Boral racks, DTE is proposing to place neutron absorbing inserts (NETCO type) into the BoraflexracksFermi 2 License Amendment Pre-Submittal Meeting Background 5Spent Fuel Pool Layout*Current SFP layout based on UFSAR Figure 9.1-3 (sheet 3) oBoraflexstorage racks shown in white oBoral storage racks shown in yellowFermi 2 License Amendment Pre-Submittal Meeting 6*DTE is requesting a license amendment to eliminate the operating license condition regarding Boraflex*The LAR will provide an updated SFP criticality analysis for the Boraflexracks-The criticality analysis will take no credit for neutron absorption by Boraflexbut will credit NETCO type neutron absorbing inserts-Criticality analysis follows guidance in NEI 12-16, Revision 2, Draft B
-No "interim" criticality analysis will be included
-Criticality analysis to be discussed further in closed (proprietary) session*LAR will be similar to those previously reviewed and approved by NRC such as Quad Cities, Peach Bottom, and LaSalleFermi 2 License Amendment Pre-Submittal MeetingLicense Amendment Request Overview 7*Additional analyses for the inserts will address:-Structural and seismic considerations-Thermal-hydraulic evaluations*LAR will also include enclosures for:-NETCO reports
-Criticality analysis report by GNF (proprietary & non-proprietary versions)
-Affidavit (for withholding proprietary version)Fermi 2 License Amendment Pre-Submittal MeetingLicense Amendment Request Overview 8*In addition to removal of the license condition, other proposed changes to the Technical Specifications (TS):-TS 4.3.1.a will be revised to slightly reduce the maximum k infinity(peak in-core kinfinity limit)-TS 4.3.1.c will be modified to describe the NETCO inserts as the neutron absorbing material rather than Boraflex-TS 5.5.13 will be eliminated since monitoring the neutron absorbing properties of Boraflexwill not be necessaryFermi 2 License Amendment Pre-Submittal MeetingLicense Amendment Request Overview 9*License Renewal added "Neutron-Absorbing Material Monitoring Program" to Fermi 2 UFSAR Section B.1.27*UFSAR Section B.1.3 states that all neutron-absorbing material to be credited during the period of extended operation will be managed by the program described in UFSAR Section B.1.27*The program currently only applies to Boral, but would apply to the new inserts as soon as they are credited*The program includes periodic inspection, testing, and monitoring
- Additional enhancements to the program, such as inspection frequency and coupon trending, are required to be implemented six months prior to the period of extended operation (September 20, 2024) as part of License Renewal commitmentsFermi 2 License Amendment Pre-Submittal MeetingLicense Amendment Request Overview 10*Target date for submittal is late 2018*Installation of inserts may be performed under 10 CFR 50.59, but no credit for neutron absorption will be taken prior to LAR approval and
implementation*Installation schedule is based around refueling outage schedules, but is targeted to begin in the fall of 2020*Completion of installation and implementation of LAR, when approved, is targeted for summer of 2021*This tentative schedule allows for elimination of the Boraflexlicense condition several years before the required deadline of March 20,
2025Fermi 2 License Amendment Pre-Submittal MeetingLicense Amendment Request Overview 11l June 27, 2018 l © 2014 Curtiss-Wright Nuclear Division NETCO SNAP-IN Rack Inserts: Neutron Absorber Panels for Fermi Boraflex
Spent Fuel Racks 12l June 27, 2018 l © Curtiss-Wright What are NETCO-SNAP-IN Inserts?Designed to Retrofit Operating Spent Fuel Pool Storage Racks.
-Replaces or supplements existing neutron absorber
-Friction fit keeps it in place without need for separate mechanical retentionAllows Continued Use of Current Fuel Storage Rack-Avoid cost of rack replacement
-Avoid personnel dose from rack replacement
-Avoid cost of old rack disposalMinimizes the impact to fuel handling and storage operations
-Minimum Profile in CellMade from Aluminum-B 4C CompositeOnce Installed, NETCO-SNAP-IN Inserts are an Integral Part of the Rack Module 13l June 27, 2018 l © Curtiss-Wright ApplicationWhen Placed in Each Storage Location, the NETCO-SNAP-IN Inserts Can Completely Replace the Neutron Poison in the Existing
Racks Already Installed in Multiple BWR Rack Types
-Westinghouse
-Joseph Oat*
-US Tool and DieOnce Installed, Fuel Can Be Moved In and Out of the Storage Locations
as UsualConsideration of Other Rack Regions Will Dictate Insert Orientation to Address Interfaces 14l June 27, 2018 l © Curtiss-Wright Install Base -BWR RacksLAR Approval Was Granted 1/28/114073 Inserts Installed In Less Than 1 YearInstallation Rate Averaged About 20 Inserts Per DayNo Longer Credits BoraflexLasalleNETCO-SNAP-IN Insert Installation Won 2013 TIP Award
-"The inserts are currently the most feasible and economic solution to Boraflexdegradation
available." RTA -W1100N.16BLAR Approval Was Granted 12/31/2014Installed Inserts In Advance Of LAR ApprovalInstallation Complete In 2014No Longer Credits BoraflexPeak Installation Rate Of About 100/DayRTA-W1100N.17BLAR Approval Was Granted 5/21/2013Over 7000 Inserts Installed on schedule.Installation completed in 2016.Install rate approached 50-60/day; Less rapid than J. Oat racks due to
"formed" and "resultant" cells.RTA-W1100N.19B LASALLE QUAD CITIES*PEACH BOTTOM 4073 Inserts 7554 Inserts 7638 Inserts 15l June 27, 2018 l © Curtiss-Wright NETCO-SNAP-IN Insert Design and Testing Requirements Analysis*Criticality Hold Down Requirements*Fuel Fit Requirements
- Rack Dimensional Variance Analysis Prototype Development*Site Specific Design Drawings*Rack Mock-Ups
- Functional Tests
- Clean Environment Testing prior to actual pool testingDimensional Testing*Un-Borated Absorber Fit Test*Variance Analysis
- Retention Force Testing
- Clean Environment Testing prior to actual pool testingThree Major Phases 16l June 27, 2018 l © Curtiss-Wright Produced to Significantly Exceed Minimum Certified Value Material Performance Testing
- Multiple Surveillance Test Results Show Consistency with Accelerated Test Predictions
- Recent coupons showed no indication of excessive corrosion or mass loss (less than the acceptance criteria of <0.05mil/yr)
- Areal density changes from -0.7% to +0.8%Material Qualification Testing
- Sheet Produced Typically Exceeds Minimum Certified Value by Significant Margin
- We Perform All Neutron Attenuation Testing At Our Facilities In Penn State
- Tensile Coupon and ICP Analysis Testing Ensure Consistent Material Performance
- 100% Material Sampling (on all billets and insert blanks)Robust Neutron Absorber QualificationExample Only: Not based on Fermi
Specific Areal Density.
17l June 27, 2018 l © Curtiss-Wright Material Monitoring ProgramCoupon Surveillance Programs will be similar to previous Insert programs with enhancements to align with NEI 16-03
-Short Coupon Monitoring Program
-Full Insert Inspection ProgramTwo Coupon Trees
-General and Galvanic Couples
-Bend CouponsMaterial Qualification Report Including Accelerated Corrosion Test Results
-Initial Accelerated Corrosion Testing includes RTA material with boron carbide loadings up to 25 v/o.
18*DTE plans to submit a LAR in 2018 to allow credit for neutron absorbing inserts in the SFP criticality analysis*The LAR will allow elimination of an operating license condition that was imposed during license renewal*Questions?
- Feedback?Summary / Questions / NRC FeedbackFermi 2 License Amendment Pre-Submittal Meeting