ML19338C882
| ML19338C882 | |
| Person / Time | |
|---|---|
| Issue date: | 12/04/2019 |
| From: | Jennifer Whitman NRC/NRR/DSS/SFNB |
| To: | |
| References | |
| Download: ML19338C882 (9) | |
Text
Public Meeting on Comment Resolution:
Draft Interim Staff Guidance for Chromium-Coated Cladding Josh Whitman, NRR December 4, 2019
Background
- September 2018: NRCs Accident Tolerant Fuel (ATF) Project Plan issued (ML18261A414)
- October 2018: Electric Power Research Institute (EPRI) Coated Cladding Gap Analysis
- November 2018: Nuclear Energy Institute In-Reactor Screening Review
- January 2019: Initial report on degradation and failure mechanisms of Cr-coated cladding issued
- April 2019: Expert panel convened to conducted phenomena identification and ranking table (PIRT)
- June 2019: Final PIRT report on degradation and failure mechanisms of Cr-coated cladding issued (ML19172A154) 2
ISG Development Timeline
- July 18, 2019: Initial public draft issued
- August 06, 2019: Public meeting to solicit stakeholder feedback
- September 17, 2019: ACRS Subcommittee briefing
- October 24, 2019: Issue in Federal Register for public comment
- December 4, 2019: Public meeting on comment resolution
- Late December 2019: Send to OMB for CRA review
- After CRA review (February?): Final issuance of ISG 3
Prior comments about material properties have been considered
- Emissivity
- Identified as less important by the PIRT
- Stakeholder identified reduced external emissivity as area where current cladding properties are non-conservative
- ISG has been modified to account for this
- Oxidation rate
- Replaced cracked coating suggestion with intentionally damaged
- Noted possible use of non-fueled data
- Tweaked language for other properties to avoid implying specific testing requirements 4
Prior comments about SAFDLs have been considered
- Discussion on boiling crises updated based on feedback
- Contradictory statements in different appendices were clarified
- General request was made to clarify testing expectations
- Not directly addressed. Difficult to do generally without being overly prescriptive 5
Stakeholder comments received before noticed comment period
- Clarify that conservative models or assumptions could be defined where data does not yet exist
- Requirements for crack inspection and performance testing need to support performance benefits / assumptions claimed
- NRC accepted these suggestions 6
Comments submitted during formal notice period
- Comment: Industry recognizes the importance of process controls in manufacturing, but believes that the NRC should not license specific manufacturing processes.
- ISG text should be clarified that the specifics of the manufacturing process should not be included in the licensing criteria.
- NRC Response: It is the responsibility of the applicant to provide a definition of the product under review. If the applicant must include process parameters to do this then they may be appropriate.
7
Comments submitted during formal notice period
- Comment: Fuels continue to lag behind the rest of the NRC in becoming riskinformed. Add language that fuel and supporting systems should be used to make reasonable assurance determination.
- NRC Response:
- Changes suggested are outside the scope of the ISG
- Fuel has a large impact on safety and risk, but
- NRC has and will continue to work to better risk inform fuels licensing 8
Questions and Comments?
9