ML061590322
| ML061590322 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 06/01/2006 |
| From: | Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML061590322 (15) | |
Text
//!--EnterWy ANO SFP Storage Project June 2006 Purpose ANO-1 Spent Fuel Pool (SFP) Project-Metamic Poison Insert Assemblies (PIAs) Design-ANO-1 Technical Specification (TS) changes and timing" ANO-2 SFP Project-Partial Re-rack-ANO-2 TS changes and timing" Schedule Constraints 1
-1Ente ANO-1 SFP Design* The ANO-1 SFP is currently divided into Region 1 and Region 2.* Region 1 contains Boraflex.
-Region 2 does not contain poison materials; fuel assembly storage is restricted in accordance with ANO-1 TS.* Soluble boron is not credited in ANO-1 criticality analysis.3-Entergv ANO-1 SFP Layout Region I Proposed Region 2 Region 2 10xllt Region 3 11 xll 11xll 11 x 12 Region I Proposed Region 2 Region 2 1OXIl xRegion 3 11 x 11 lix1i 11 x 12 2
--_Entergy ANO-1 SFP Loading* Boraflex in Region 1 is degrading.
-August 2002 Region 1 SFP racks were considered operable but degraded as allowed by GL 91-18.-April 2007 -Credit will no longer be taken for Boraflex resulting in a loss of full core offload capability.
- Current fuel loading strategy includes loading 3 dry casks prior to the spring 2007 refueling outage.5 Enterg ANO-1 Metamic Project Overview" To provide an area where unrestricted storage is available, a portion of Region 2 will be defined as Region 3." Metamic PIAs will be installed in the existing rack flux traps of Region 3." U-235 fuel enrichment will be increased from 4.1wt.% to 5.Owt.% for future core reload flexibility." Soluble boron will be credited as allowed by 1 OCFR50.68.
6 3 gEnty Metamic Overview Metamic has been approved for use in Fuel Pool applications by N RC letter to Entergy dated June 17, 2003.Conditions and Limitations of NRC Safety Evaluation include:-Coupon Sampling Program-Discussion of coupons-Description of anodizing process and cleaning techniques (not using anodizing process)-B 4 C content less than 31wt.% (using 25wt.%)7 SEnterg, ANO-1 Current Project Status" Criticality analyses have been performed to analyze-Region I racks with no credit for Boraflex-Region 2 racks with no poison insert material-Region 3 racks with Metamic PIAs-New Fuel Vault and fuel handling equipment" Structural
/seismic for Region 3 racks and pool analyses considering poison insert design and additional weight.* Thermal hydraulic analysis* Postulated fuel assembly drop events for Region 3 of SFP racks.* Evaluation of potential offsite and control room dose radiological consequences of a Fuel Handling Accident (FHA) is currently reflected in the ANO-1 SAR.4
-Entergy PIA Design Modifications Original PIA design, as previously submitted to the NRC, was a collapsible design for insertion and expanded to fill the flux trap.Revised PIA design is a non-collapsible fixed design.PIA Design Overview* PIA length is -13 feet; active fuel length-12 feet.* PIA width is 7.12 inches.* PIA thickness 1.20 inches.* PIA weight -50 lbs. each.* External SS sheaths along the full length of the PIA protects the Metamic@ panels when inserted in the flux trap.* Internal SS sheathing bands secure the Metamic@ panels to the external sheath.Bands are located at the ends and four locations along the length.10 5 OEntergy Top View of PIA 11 OEnteWg Stiffeners 12 6
==-Entergy Bottom View Cose-up 13 7
ýEntetW, ANO-1 Submittal History Topical Report-August 8, 2002 -Entergy submitted Topical Report "Use of Metamic In Fuel Pool Applications."-June 17, 2003 -NRC approves Topical Report." ANO-1 License Amendment-April 2, 2003 -Entergy submitted license amendment to modify spent fuel loading restrictions for Regions 1, 2, and 3.-June 24, 2004 -Entergy withdrew the license amendment due to the inability to manufacture PlAs to meet the design specifications to support the criticality analysis.15 a Entergy Project Activities The following is a summary of activities performed ince the 2004 amendment withdrawal.
-The original design concept was reevaluated which resulted in a design change to a non-collapsible, fixed design.-A comprehensive examination of the spent fuel pool (SFP)racks was performed for additional design input.-Preliminary analyses were performed and two PIAs were manufactured using the fixed design to ensure constructability.
-Performance of formal design documentation and analyses for licensing PIAs.16 8
!- EnterW ANO-1 Proposed Licensing Amendment License amendment reflects new design and will include the following:
-Storage restrictions for SFP where appropriate.
-Boron credit-Compliance with 10 CFR 50.68(b).-Fuel enrichment increased from 4.1wt%. to 5.Owt.%-Metamic Coupon Sampling Program will be added.17 MEntergy ANO-1 Submittal Plans* LAR submitted by July 2006 with approval by January 15, 2007.* Advantage-Allows insertions of PIAs in January/February 2007.-Allows full core offload following outage.e Disadvantage
-NRC review time shortened.
18 9
Other ANO-1 Options Considered Continue to address ANO-1 SFP conditions as degraded with alternate loading scheme-Requires applying the Region 2 rack analysis to Region 1 under 10 CFR 50.59 using the current licensing basis and accounting for the Boraflexstructure without crediting its neutron absorption capability.
-Allows full core offload capability for spring 2007 outage, but not after the outage.19 Entergy Other ANO-1 Options Considered Insert PIAs in January under 50.59-Requires analytical confirmation of current licensing basis for." Criticality analysis" Structural analysis-Allows NRC review time to be extended from January to March 2007.-Allows full core offload capability when Metamicamendment is approved.-Substantial analysis for short duration.20 10 Entergy ANO-2 SFP Project ANO-2 Project Overview* The ANO-2 Spent Fuel Pool (SFP) is currently divided into Region 1 and Region 2.* Region I racks contain Boraflex that is no longer credited.* Region 2 racks do not contain poison materials.
- Flux trap dimensions in Region 2 racks prohibit PIA insertion.
Region I racks will be replaced with Metamic racks restoring unrestricted fuel assembly storage.22 11 7Enterg ANO-2 SFP Layout Region 2 Region 2 FL-iion 2 Region 1 9X9 8X10 9X10 9X9 Region 2 Region 2 Region 2 Regioni1 9X9 9XI0 9X10 S9x Region2 Region 2 Region 2 Regioni1 SX9 SX10 axi0 8X9 23 a-Entergy ANO-2 Project Overview* Current loading pattern is complex.* -1/2 of fuel assemblies in the core are replaced each cycle. Minimal cooling time is 5 years prior to loading fuel in a dry fuel cask; however time is typically longer.* Currently, all available fuel is loaded into dry fuel casks.* More fuel assemblies will be available to load into dry fuel casks by June 2007.Window of opportunity (due to other competing SFP activities) for re-rack September
-December 2007.24 12 ANO-2 License Amendment History Topical Report-August 8, 2002 -Entergy submitted Topical Report "Use of Metamic In Fuel Pool Applications."-June 17, 2003 -NRC approves Topical Report.ANO-2 License Amendment-January 29, 2003 -Entergy submitted license amendment to modify spent fuel loading restrictions for Regions 1, 2, and 3.-August 26, 2003 -Entergy withdrew the license amendment due to extrusion problems.25'"-Enterg Project Activities The following is a summary of activities performed since the 2003 amendment withdrawal.
-Alternate loading pattern TS change submitted and approved.-The original design concept was reevaluated which indicated that a design similar to ANO-1 cannot be manufactured for ANO-2 due to the smaller flux trap.-A comprehensive examination of the SFP racks and other designs was performed.
-Partial re-rack resulted in only viable option that results in unrestricted storage.26 13 4 Entergy ANO-2 Proposed License Amendment The proposed amendment will reflect the partial re-rack and include the following:
-New storage restrictions.
-Increase in fuel enrichment from 4.55wt% to 5.Owt.%.-Boron credit (ANO-2 currently complies with I OCFR50.68(b)).
-Add Metamic Coupon Sampling Program.27 OEntergy ANO-2 Submittal Plans" Submit by December 31, 2006" Requested approval by September 1, 2007.28 14
< EnterW Schedule Constraints Common SFP floor and equipment Activities in ANO-1 and ANO-2 SFPs-March -April 2006 loaded 3 casks for ANO-2.-May 2006 reconfigured ANO-2 SFP for new fuel receipt and to support criticality analysis for fuel core offload.-June 2006 new fuel receipt ANO-2.-July 2006 load 2 casks for ANO-1.-Sept. -Oct. 2006 ANO-2 Refueling Outage.-Nov. 2006 load 1 cask for ANO-1.-Jan. -February 2007 Insert PIAs in ANO-1 SFP.-March 2007 new fuel receipt and fuel reconfiguration ANO-1.-April 2007 -ANO-1 Region 1 Boraflex no longer credited.-April -May 2007 ANO-1 Refueling Outage.-June 2007 load 2 casks for ANO-2.-July 2007 load 2 casks for ANO-1.-September
-December 2007 partial re-rack ANO-2.-Jan/Feb 2008 -New fuel receipt ANO-2.AEnterg Summary ANO-1 SFP Project-Metamic PIAs need to be inserted in the SFP in January / February 2007.-Unless PIA insertion can be accomplished prior to the approval of the TS, license amendment approval is needed by January 15, 2007.* ANO-2 SFP Project-Partial Re-rack-License amendment approval needed by September 1, 2007.30 15