ML19345F191
| ML19345F191 | |
| Person / Time | |
|---|---|
| Issue date: | 12/12/2019 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Burton W | |
| References | |
| Download: ML19345F191 (38) | |
Text
Subsequent License Renewal (SLR)
Lessons Learned Public Meeting #2 December 12, 2019
AGENDA Welcome and Introductions
Background
Criteria to Identify Issues to be Included in ISGs Proposed GALL-SLR and SRP-SLR Revisions Industry Presentations Other Topics Summary Closeout and Adjourn 2
BACKGROUND
- NRC established an optimized 18-month review schedule for SLR applications
- Piloted on the River Bend license renewal application -
completed in 16 months
- NRC has received 3 SLR applications for review since January 2018
- First Lessons Learned Meeting March 28, 2019
- Agreed to focus efforts on identifying revisions to the GALL and SRP to improve effectiveness and efficiency of the preparation and review of future SLR applications
- Issue ISGs (may consider direct update of the GALL and SRP) 3
CRITERIA TO IDENTIFY ISSUES TO BE INCLUDED IN SLR ISG (or in GALL and SRP)
- Aligns with industry priorities
- Reduces/eliminates RAIs
- Reduces/eliminates plant-specific AMPs
- Reduces/eliminate exceptions and enhancements
- Reduces/eliminates F-J notes
- Incorporates latest guidance
- Resolves errors and provides clarifications
- Reduces applicant and staff work 4
Proposed Revisions to GALL-SLR Chapter I: Application of ASME Code Chapter I in the GALL-SLR Report, Volume 1, provides guidance on how to apply the ASME Boiler and Pressure Vessel Code for aging management activities Current guidance provided in the report remains applicable for use by SLRA applicants Staff will need to make sure editions of ASME Section XI in Table I-1 of the GALL-SLR report are up to date with the latest versions of the Code endorsed in 10 CFR 50.55a 5
Proposed Revisions to GALL-SLR and SRP-SLR Clarify 2.5.2.1.1, Components Within the Scope of SBO (10 CFR 50.63), to specifically address alternate AC source and any cross-ties that may be stipulated for recovery from SBO Clarify some of Table 1 electrical items in SRP section 3.6 and GALL-SLR Table 2 in chapter VI (e.g. transmission conductors, cable bus)
SRP section 3.6.2.2.3 and Table 1
- Expand on definition of wind-induced abrasion (sand or other particles impacting transmission conductors and causing loss of material) 6
Proposed Revisions to GALL-SLR and SRP-SLR
- XI.E1, Electrical Insulation for Cables and Connections not subject to EQ
- Clarify for inspections and aging management of cables that are coated with fire retardant material.
- Clarify to specifically include mechanical components associated with electrical equipment (gaskets, seals, O rings, etc.) that are in the scope of the AMP.
7
Proposed Revisions to GALL-SLR and SRP-SLR
- XI.E6, Electrical Cable Connections Not Subject to EQ
- Clarify to caution against re-torquing connections as part of inspections and testing.
- XI.E7, High-Voltage Insulators
- Clarify for aging management of polymer high-voltage insulators.
- Clarify to include medium-voltage insulators that are on SBO recovery path 8
Proposed Revisions to GALL-SLR and SRP-SLR
- Review latest version of IEEE standards for update in the AMPs 9
Proposed Revisions to GALL-SLR and SRP-SLR Add new FE 3.5.2.2.2.7 for Reactor Pressure Vessel (RPV) steel supports and associated new SRP-SLR Table 3.5.1 and GALL-SLR AMR line items to address loss of fracture toughness due to irradiation embrittlement Add the Wooden Poles aging management recommendations to the Structures Monitoring AMP, and add the new SRP-SLR Table 3.5.1 and GALL-SLR AMR line item to address the associated aging effects under the SMP 10
Proposed Revisions to GALL-SLR and SRP-SLR
- Revise/supplement applicable sections of SRP-SLR and GALL-SLR to address loss of fracture toughness due to irradiation embrittlement for reactor vessel steel supports. Specific updates to AMR line items, FE, and/or TLAA guidance to be determined 11
Proposed Revisions to GALL-SLR and SRP-SLR
- XI.S3 - IWF
- Enhance program elements to manage the effects of aging on RPV steel support structure due to radiation, if applicable 12
Proposed Revisions to GALL-SLR and SRP-SLR XI.S6 - Structures Monitoring
- Add the Wooden Poles aging management recommendations to the Structures Monitoring AMP, and add the new SRP-SLR Table 3.5.1 and GALL SLR AMR line item to address the associated aging effects under the SMP 13
Proposed Revisions to GALL-SLR Chapter IX: Use of Terms
- Reevaluate the Chapter IX description of the term groundwater/soil 14
Proposed Revisions to GALL-SLR and SRP-SLR ISG-SLR for PWR Vessel Internals
- Update AMP XI.M16A and FE 3.1.2.2.9 to reference latest industry guidelines; adjust AMR line items
- Incorporate gap analysis lessons learned from first two PWR SLRAs and recent industry interim guidance 3.1.2.2.4 Item 2 (Isolation condensers)
- only 3 operating units with isolation condensers (ICs)
- Discuss whether AMR items for ICs are still necessary
- If industry still desires AMR items for ICs, work with industry to establish which water chemistry or non-Class 1 inspection AMPs should be applied to ICs
- Eliminate AMR FEs as appropriate (3.1.2.2.4.2/3.1.3.2.2.4.2 and 3.1.2.2.7/3.1.3.2.7) 15
Proposed Revisions to GALL-SLR and SRP-SLR 3.1.2.2.6 Item 1 - Stress Corrosion Cracking (SCC) in stainless steel bottom-mounted instrument guide tubes
- Reference ISI and Water Chemistry Programs with no need for FE 3.1.2.2.6 Item 2 - SCC in Class 1 CASS
- Cite ISI and Water Chemistry Programs
Proposed Revisions to GALL-SLR and SRP-SLR XI.M9 and related AMR bases - BWR Vessel Internals
- Revise to keep referenced reports in GALL-SLR AMP up to date to staff-approved BWRVIP topical reports
- Examples may be BWRVIP-25, Rev. 1, BWRVIP-76, Rev. 1-A, etc.
- Check SRP-SLR 3.1.2.2.12/3.1.3.2.12, 3.1.2.2.13/3.1.3.2.13, and 3.1.2.2.14/3.1.3.2.14 for necessary changes.
17
Proposed Revisions to GALL-SLR and SRP-SLR FE 3.1.2.2.11
- Provide better direction on SG divider plate cracking 18
Proposed Revisions to GALL-SLR and SRP-SLR: Aging Management Programs
- XI.M17 - Flow Accelerated Corrosion
- Clarify scope expansion requirements
- Clarify use of CHECWORKS erosion module 19
Notes F-J
- Generic Note G
- Use of XI.M30 (Fuel Oil Chemistry) to manage LOM in Ni alloy strainer elements exposed to fuel oil (externally)
- Generic Note H
- Manage wall thinning/erosion in carbon steel insulated piping and piping components exposed to closed cycle cooling water (internally) with the Flow-Accelerated Corrosion AMP
- Loss of material for carbon steel in a sodium pentaborate environment
- reduction of heat transfer for heat exchanger exposed to fuel oil 20
Proposed Revisions to GALL-SLR and SRP-SLR: Aging Management Programs
- XI.M33 - Selective Leaching
- To implement the reduced extent of inspections as recommended in the SLR AMP, the applicant needed to conduct the inspection sample size as recommended in GALL Report, Rev 2 during initial LR
- Acceptance Criteria: Last sentence to be corrected to cite criterion (d) instead of criterion (c) 21
Proposed Revisions to GALL-SLR and SRP-SLR: Aging Management Programs
- XI.M41 - Buried and Underground Piping and Tanks
- Use of 100 mV polarization acceptance criterion
- Clarify plant-specific OpE for buried components
- Revise Category F inspection recommendations
- Revise Preventive Actions element
- EPRI document on soil corrosivity 22
Proposed Revisions to GALL-SLR and SRP-SLR Long-term loss of material for 3.1 systems
- Reactor coolant only has Table 1 items for BWR plants
- Potential that a PWR might have steel piping exposed to treated water without corrosion inhibitors High Density Polyethylene (HDPE)
- No aging mechanism cited for AP-175, A-406, AP-239, A-739, and A-648 Expand the number of AMR items and clarify aging effects for copper alloy greater than 15 percent zinc exposed to air or condensation. Reflect that more than trace amounts of ammonia are needed to cause cracking.
23
Proposed Revisions to GALL-SLR and SRP-SLR
- Possibly revise the wide-spread citing of crevice corrosion as an aging mechanism for steel piping
- Crevice corrosion of carbon steel is only applicable where the metal is in an alkaline environment that promotes a passive film. In acidic conditions, carbon steel is susceptible to general corrosion 24
Proposed Revisions to GALL-SLR and SRP-SLR: Aging Management Programs
- XI.M2 - Water Chemistry and
- XI.M21A - Closed Treated Water Systems
- Update EPRI document references 25
Proposed Revisions to GALL-SLR and SRP-SLR
- Develop a new further evaluation section to address flow blockage due to fouling in treated water systems and loss of material for steel piping in closed-cycle cooling water systems without corrosion inhibitors
- Incorporate recommendations for managing aging effects of carbon fiber wrap material installed on the inside diameter and outside diameter of components 26
Proposed Revisions to GALL-SLR and SRP-SLR: Aging Management Programs
- XI.M38 - Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components
- Inspections where piping and tanks are exposed to an air-water interface
- May apply to other AMPs 27
Proposed Revisions to GALL-SLR and SRP-SLR: Aging Management Programs
- AMP XI.M32, One-Time Inspection,
- Incorporate an incubation period for repairs or replacements that are used to correct a condition adverse to quality related to adverse plant-specific operating experience
- Inspections of stainless steel and aluminum support structures should be inspected for cracking using VT-1 or surface examination 28
Proposed Revisions to GALL-SLR and SRP-SLR:
Engineered Safety Features Recurring Internal Corrosion
- Revise the current criteria to require reviewing plant-specific operating experience for both a 5-year and 10-year period; rather than allowing either one of the two periods to be acceptable
- Revise the information to be provided in the SLRA to include a breakdown of instances where the RIC criteria have been exceeded 29
Proposed Revisions to GALL-SLR and SRP-SLR:
Engineered Safety Features Aluminum T6063-T6
- Add to the list of aluminum material specs that are not susceptible to cracking Revise drain down recommendations for fire water hydrants to provide flexibility in relation to frost line and other risk-informed enhancements 30
Proposed Revisions to GALL-SLR and SRP-SLR
- Clarify that the flange location wear is also included in the FE scope as well as the wear at the location the thermal sleeve exits from CRDM nozzle
- Add recent OpE and related references regarding thermal sleeve wear at the flange location
- Update industry guidelines for this item and related information may be considered, too.
31
Proposed Revisions to GALL-SLR and SRP-SLR
- New FE Section - Thermal Fatigue
- Address cracking due to thermal fatigue in reactor coolant pressure boundary
- Include applicable industry guidelines
- Applicant should identify its program to manage cracking due to thermal fatigue and evaluate the effectiveness of the program
- Recent OpE supports the need to add the new FE section.
32
Proposed Revisions to GALL-SLR and SRP-SLR: Aging Management Programs
- XI.M3 - RV Head Closure Stud Bolting
- Delete the words for newly installed studs and for existing studs in item (d) of the preventive actions program element
- Either 150-ksi yield strength or 170-ksi ultimate tensile strength may be used to determine the susceptibility of studs to SCC 33
Proposed Revisions to GALL-SLR and SRP-SLR: Aging Management Programs
- XI.M12 - Thermal Aging Embrittlement of CASS
- Add NUREG/CR-4513, Rev 2
- Add Code Case N-838 as an acceptable flaw tolerance evaluation method (as will be approved in RG 1.147, Rev 19)
- Potentially revise the acceptance criteria program element
- The current element indicates the ASME Code does not contain evaluation procedures for CASS with ferrite content 20 percent. The 2019 Edition of the ASME code includes flaw evaluation methods for CASS piping with ferrite content 20 percent. This change may be added to the AMP 34
Proposed Revisions to GALL-SLR and SRP-SLR: Time-Limited Aging Analyses TLAA 4.2 - RPV Neutron Embrittlement Analyses
- Update USE/EMA TLAA guidelines (SRP-SLR 4.2.2.1.2
/4.2.3.1.2) to reflect new 80 staff-approved generic EMA reports for PWR RPV components TLAA 4.7 - Other Plant-Specific TLAAs
- Add review sections for
- Flaw tolerance evaluation for PWR CASS pump casings (e.g., Code Case N-481 and PWROG 17033)
- Leak-before break (including evaluation of thermal aging
- Recent SLRAs include these plant-specific TLAAs. Currently, SRP-SLR does not include specific review sections for these TLAAs 35
Other Topics SRP-SLR Section 1.2.3 on AMPs that rely on Industry Topical Reports (TRs)
- May add guidance that generic aging conclusions drawn by vendors or industry organizations in referenced TRs might be invalidated by plant-specific criteria
- Examples, lack of AERM conclusions drawn in TRs might be invalidated by assumptions used in site-specific TLAAs or by generic or plant-specific operating experience with the aging effects ISGs vs direct revision to GALL-SLR and SRP-SLR Other Topics 36
Next Actions
- Proposed ISG/SLR update development schedule
- Process improvements
- Risk informing SLR reviews 37
DISCUSSION 38