ML18184A521
| ML18184A521 | |
| Person / Time | |
|---|---|
| Site: | 07200020 |
| Issue date: | 05/29/2018 |
| From: | Kristina Banovac Renewals and Materials Branch |
| To: | Michael Layton Division of Spent Fuel Management |
| Banovac K | |
| Shared Package | |
| ML18184A515 | List: |
| References | |
| CAC 000993, CAC 001028, EPID L-2017-LNE-0007, EPID L-2017-RNW-0019 | |
| Download: ML18184A521 (35) | |
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E Environmental Management October 2005 Ashtabula 2000 Ashtabula 2006 DOE-Idaho Briefing to NRC on TMI-2 ISFSI License Renewal Application RAI Responses White Flint, MD June 7, 2018
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E Environmental Management 2
Agenda
- Opening Remarks
- RAI Response Status
- RAI Discussion 1: Component Safety/Quality Classifications 4: Transfer Cask Aging Management Review 8: Licon Role in Criticality Analysis 11: TMI-2 Canister Corrosion
- Closing Remarks
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E Environmental Management 3
RAI 2-1
- RAI Summary: Clarify the use of FSAR and design drawings in the scoping evaluation and address any apparent discrepancies in component safety classifications between the two drawings
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RAI 2-1: Overview The TMI-2 ISFSI FSAR contains representative drawings from the associated design drawings Major in-scope components:
- TMI-2 canisters - fuel, knockout, and filter
- Horizontal Storage Modules (HSMs)
- Dry Shielded Canisters (DSCs)
- Transfer Cask (TC)
- ISFSI basemat and approach slab Subcomponents of major components are scoped separately The ITS quality category (A, B, or C) is immaterial to scoping; all ITS items are in-scope by definition NITS items are scoped based on whether their failure would have a deleterious effect on an intended function
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RAI 2-1: Overview LRA Table 2-1 provides the major component scoping conclusion and applicable criterion LRA Table 2-2 lists the FSAR and design drawings for each major component used for scoping its subcomponents LRA Table 2-3 provides the scoping conclusion, applicable criterion, and intended function(s) for scoping the subcomponents of each major component LRA Table 2-4 lists out-of-scope subcomponents To scope each subcomponent, details from drawings and other documents were used, if necessary, e.g., Quality Category Assessments (QCAs)
Each major component will be addressed separately here This discussion will be summarized in the RAI 2-1 response
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E Environmental Management 6
RAI 2-1: TMI-2 Canisters
- The TMI-2 canisters were designed and fabricated for removal of the debris from the TMI-2 core in early 1980s
- 10 CFR 72 was not a consideration at the time the TMI-2 canisters were designed and fabricated for the TMI-2 site
- Part 72 safety classifications are not assigned for TMI-2 canisters
- TMI-2 canisters are shown on the following drawings:
Component Design Drawing FSAR Drawing*
Fuel Canister 1154070-F 1161300-D Knockout Canister 1154041-F 1161301-D Filter Canister 1154018-F 1161299-D
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RAI 2-1: TMI-2 Canisters
- There are no intact fuel assemblies in the TMI-2 ISFSI DSCs - all core debris material is in a TMI-2 canister
- TMI-2 canisters were scoped in as fuel assemblies because they set the geometric positioning of the fissile material - consistent with NUREG-1927
- The TMI-2 canisters are unique from fuel assemblies in that they contain materials such as Boral and low-density concrete (Licon)
- FSAR safety analyses were used to scope TMI-2 canister subcomponents based on intended function
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RAI 2-1: TMI-2 Canisters - Summary
- No Part 72 safety classifications assigned
- Scoped in as fuel assemblies per NUREG-1927, Section 2.4.2.1 (LRA Criterion 3)
- Design drawings used to evaluate subcomponents
- No safety classification or quality category assigned
- Consistent with NUREG-1927 for fuel assembly scoping
- LRA Table 2-3 summarizes the in-scope TMI-2 canister subcomponents based on function
- LRA Table 2-4 lists out-of-scope TMI-2 canister subcomponents
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RAI 2-1: Dry Shielded Canisters
- TMI-2 DSCs are vented to the HSM space with filters
- Filter purge and surveillance capability provided
- Vent and purge port assemblies have storage and transportation configurations
- From LRA Table 2-2:
DSC Subcomponent Design Drawing FSAR Drawing Basket Assembly 219-02-1000 219-02-2000 Shell Assembly 219-02-1001 219-02-2001 Basket-Shell Assembly 219-02-1002 219-02-2002 Main Assembly 219-02-1003 219-02-2003 Purge Port Filter Assy 219-02-1010 219-02-2010 Vent Port Filter Assy 219-02-1011 219-02-2011
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E Environmental Management 10 RAI 2-1: Dry Shielded Canisters DSC FSAR and design drawings both include quality categories but are deliberately not consistent DSC subcomponents were classified on the design drawings as either ITS-A or NITS to simplify procurement Some ITS subcomponents are classified on the FSAR drawings as ITS-B or ITS-C - this is, and remains the licensing basis quality category ITS subcomponents were fabricated, installed, tested, inspected and qualified per ITS-A as shown on the design drawings
- Conservative approach with respect to the licensing basis depicted on the FSAR drawings One additional clarification to be discussed later
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E Environmental Management 11 RAI 2-1: Dry Shielded Canisters
- Example: DSC grapple ring and support (Items 4 and 5)
FSAR drawing 219-02-2001 (ITS-B):
Design drawing 219-02-1001 (ITS-A):
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E Environmental Management 12 RAI 2-1: Dry Shielded Canisters - Clarification LRA Table 2-4 includes several DSC subcomponents classified as ITS-A on the FSAR drawing but listed as out-of-scope for the LRA These subcomponents are part of the DSC vent and purge port cover configuration (FSAR Figures 4.3-1 and 4.3-2)
DOE-ID modified the DSC hydrogen sampling configuration and subcomponents shown on the FSAR figures and in the drawings and no longer samples in this fashion (affects Bill-of-Material (BOM) Items 2, 11, 15, and 22)
Original subcomponents not installed during normal storage operation and no longer used for sampling
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E Environmental Management RAI 2-1: Dry Shielded Canisters - Clarification 13 FSAR Figure 4.3-1 DSC Vent and Purge Port Assemblies 2
11 15/22
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E Environmental Management RAI 2-1: Dry Shielded Canisters - Clarification 14 FSAR Figure 4.3-2 DSC Sampling System
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E Environmental Management 15 RAI 2-1: Dry Shielded Canisters - Clarification Current method of hydrogen sampling is via connection in a different sample cover design that allows for drawing sample gas through the HEPA filters (Ref. INL drawing 623548)
These new sampling components have no storage safety function and are classified as commercial grade (NITS)
Original subcomponents would only be installed for Part 71 transportation and are therefore outside LRA scope DOE-ID has initiated a corrective action item to address this configuration mismatch among FSAR and drawings and will make appropriate document changes before the RAI response The RAI response will explain the resolution with respect to the LRA
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E Environmental Management 16 RAI 2-1: Dry Shielded Canisters - Summary
- Design drawings assumed all ITS items were classification A for procurement/fabrication, which is conservative
- FSAR drawings are the licensing basis classifications
- No discrepancies to harmonize
- The transport/sampling subcomponent set requires a change to configuration documents to be completed before RAI response
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E Environmental Management 17 RAI 2-1: Horizontal Storage Modules
- TMI-2 HSMs are not ventilated but have a rear door with vent holes to access DSCs for sampling
- From LRA Table 2-2:
HSM Subcomponent Design Drawing FSAR Drawing HSM General Arrangement 219-02-5100 219-02-6000 Module Main Assembly 219-02-5101 HSM Base Unit 219-02-5103 HSM Roof Slab 219-02-5104 HSM DSC Support Structure 219-02-5105 HSM Hardware/Miscellaneous Doors/Fasteners 219-02-5107 HSM End Shield Wall 219-02-5108
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E Environmental Management 18 RAI 2-1: Horizontal Storage Modules
- Note 5 on the FSAR drawing includes a table that addresses quality categories of major HSM subcomponents
- 8 subcomponents addressed
- Subcomponents may have a lower quality category than the design drawings
- Items not in the table are NITS
- Washers and shims are NITS
- DSC overpack listed in table as ITS-A but not considered; will be subject to a license condition prohibiting use during normal operation (subject of RAI 2-3)
- Remainder of items in table are ITS-B
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E Environmental Management 19 RAI 2-1: Horizontal Storage Modules
- HSM FSAR drawing Note 5:
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E Environmental Management 20 RAI 2-1: Horizontal Storage Modules
- To perform a comprehensive scoping evaluation of all HSM subcomponents, the design drawings and some QCAs were used to augment FSAR drawing information
- This is a conservative approach rather than assume all subcomponents not specifically listed in the HSM FSAR drawing, Note 5 table are NITS
- The design drawings and QCAs do not classify any subcomponents lower than the FSAR drawing;
- Some subcomponents listed with higher classification for scoping based on the design drawing or QCA but are NITS in the licensing basis per FSAR drawing note
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E Environmental Management 21 RAI 2-1: Horizontal Storage Modules - Summary
- The HSM FSAR drawing broadly addresses quality classification by major HSM assembly
- The HSM FSAR drawing states items not specifically called out in the drawing table are NITS in the licensing basis
- No items are classified on the HSM design drawings or in the QCAs lower than the licensing basis classification per the FSAR drawings
- Based on the design drawings and QCAs, the LRA lists each in-scope subcomponent in Table 2-3 and each out-of-scope subcomponent in Table 2-4
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E Environmental Management 22 RAI 2-4: Transfer Cask Aging Management Review
- RAI Summary: Provide an aging management review and TLAAs/AMPs for the two transfer casks that are part of the ISFSI design basis (OS197 and MP187)
- MP187 TC is part of the Rancho Seco ISFSI license renewal recently submitted
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E Environmental Management 23 RAI 2-4: Transfer Cask Aging Management Review
- DOE-ID will propose a license condition not to use an MP187 TC aged over 20 years
- DOE intends to incorporate the TN CoC 1004 scoping, AMR, TLAAs, and AMP for the OS197 TC by reference into the TMI-2 ISFSI LRA verbatim
- The TN CoC 1004 OS197 scoping, AMR, TLAAs and AMP include proprietary information on the 72-1004 docket
- This information will not be re-submitted on the TMI-2 docket
- DOE-ID will make arrangements with TN to acquire access to the AMR/AMP
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E Environmental Management 24 RAI 2-4: Transfer Cask Aging Management Review - Summary
- License condition prohibiting use of MP187 over 20 years old
- Future license amendment would be required to change
- Retain position in the LRA to use the DOE-ID quality procurement process to ensure AMPs are implemented if a 20+ year old OS197 TC is acquired for the TMI-2 ISFSI in the future
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E Environmental Management 25 RAI 3-8: Licon Role in Criticality Analysis
- RAI Summary: Justify that changes to Licon properties as a result of aging are not important to maintaining subcriticality in the TMI-2 canisters as described in the two criticality analyses summarized in the FSAR
- Also applies to RAI 3-7
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E Environmental Management 26 RAI 3-8: Licon Role in Criticality Analysis
- Licon is present only in the TMI-2 fuel canister:
(Licon)
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E Environmental Management 27 RAI 3-8: Licon Role in Criticality Analysis Knockout and filter canisters Knockout Filter Open (Typ.)
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E Environmental Management 28 RAI 3-8: Licon Role in Criticality Analysis
- Scoping studies conducted to determine most reactive canister configuration
- Of the three TMI-2 canister types, knockout canister was analyzed for criticality as the most reactive (bounding) case
- 1,908 lbs of UO2 was modeled to envelope all canister types
- Assumes 12 close-packed (no basket) knockout canisters with DSC collapsed around canisters
- 14 liters of water allowed/canister when including 75%
boron credit, 8 liters if substituting water for the boron poison columns - all water assumed in the fuel region
- Described in FSAR Section 3.3.4 and acknowledged in SER Section 8.5.4.2
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E Environmental Management 29 RAI 3-8: Licon Role in Criticality Analysis Per LRA Reference 3.11.106, Table 18, the replacement of Licon in the fuel canisters with water shows a small peak, then negative effect on reactivity as water fraction increases to a complete replacement of Licon with water:
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E Environmental Management 30 RAI 3-8: Licon Role in Criticality Analysis - Summary
- Knockout canister criticality analysis is bounding in design basis criticality analysis
- Knockout canister does not contain Licon
- Regardless of what may happen to Licon due to aging effects in fuel canister, KO canister remains bounding
- DOE-ID intends to clarify the LRA scoping evaluation to indicate that Licon is out of scope for criticality
- Will re-assess Licon influence on other intended functions to determine if it remains in scope
- If in scope, will address applicable aging mechanisms
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E Environmental Management 31 RAI 3-11: TMI-2 Canister Localized Corrosion
- Summary: Justify why radiation-induced localized corrosion of the TMI-2 canisters is not a concern, including any indications of corrosion observed during wet storage or canister inspections prior to loading in the DSCs
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E Environmental Management 32 RAI 3-11: TMI-2 Canister Localized Corrosion
- TMI-2 canisters were shipped from the plant to INL between 1986 and 1990 and placed into wet storage at Test Area North (TAN)
- Between 1999 and 2001, 341 canisters were drained, vacuum-dried with concurrent heating, transferred into 29 DSCs and moved into ISFSI storage
- During storage at TAN and operations for ISFSI storage, DOE-ID can find no evidence of formal inspections or documented observations of the TMI-2 canisters
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E Environmental Management 33 RAI 3-11: TMI-2 Canister Localized Corrosion
- The combination of heating and drying the TMI-2 canisters and the DSCs provided high confidence that little residual moisture remained inside
- Any radiolytic oxidizing products created from gamma radiation interaction with residual water is expected to be minimal
- Similar to fuel assemblies at other ISFSIs the TMI-2 canisters cannot be inspected
- The TMI-2 canister AMR addresses several different corrosion mechanisms and finds none having effects requiring management
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E Environmental Management 34 RAI 3-11: TMI-2 Canister Localized Corrosion - Summary
- DOE-ID will revise the LRA to add radiolytic oxidizing products created from gamma radiation interaction with residual water as a potential aging mechanism
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E Environmental Management Open Discussion 35