ML25293A452

8 - NRC Review of R&D

ML25293A452
Person / Time
Site:	Kemmerer File:TerraPower icon.png
Issue date:	10/20/2025
From:	Reed Anzalone, Matthew Hiser Advisory Committee on Reactor Safeguards, NRC/NRR/DANU
To:
References
Download: ML25293A452 (1)

Text

NRC Review of Kemmerer Unit 1 Construction Permit Application Research and Development Items Reed Anzalone, Matt Hiser NRR/DANU ACRS Subcommittee Meeting October 22-23, 2025

Role of R&D in Licensing Process

• 10 CFR 50.34(a)(8) requires a CPA to identify SSCs requiring R&D to confirm the adequacy of their design

• 10 CFR 50.35(a)(3) allows the NRC to issue a CP if safety features or components requiring R&D have been described and there is an R&D program reasonably designed to resolve any safety questions

• 10 CFR 50.35(b) specifies that the NRC may incorporate provisions into the CP requiring periodic R&D progress reports

• 10 CFR 50.43(e) lists performance demonstration requirements for OL applicants with designs that differ significantly from LWRs or use simplified, inherent, passive, or other innovative means to accomplish their safety functions

• While 10 CFR 50.43(e) is not applicable to a CP, R&D activities discussed in the PSAR may support the required performance demonstrations at the OL stage 2

R&D Item Identification

• Identified using a process that considered the SSC maturity and safety functions based on the technology readiness level (TRL) concept from other government agencies (GSA, NASA, etc.)

• Staff evaluation

• TRL concept can be a reasonable indicator of the maturity of a given SSC

• TRL concept tends to focus on specific SSCs which is challenging for topics with cross-cutting applicability like material performance

• PSAR indicates that while TRL played a significant role in identifying R&D items, it was not the sole factor considered

• The staff determined, pursuant to 50.34(a)(8), that the applicant appropriately identified those SSCs requiring R&D to confirm the adequacy of their design 3

Research and Development Items

• The following R&D items have been discussed in prior presentations:

• RAC heat transfer performance

• In-Vessel Fuel Handling System Transfer Machine Grapple Finger Operation

• IHT Sodium-Salt Heat Exchanger Interaction

• Core Restraint System Compressive Assembly

• Core Validation Testing

• In-Service Structural Materials Performance

• NRC staff is proposing to include 3 conditions in the CP to require updates associated with R&D items 4

Coatings Development and Qualification

• Objective: Develop and qualify coatings for tribological performance in sodium

• Reduce wear, friction, and self-welding

• Key R&D Activities:

• Optimize deposition procedures using historical data.

• Test coating performance under environmental and functional conditions.

• Evaluate the impact of coating failure or delamination

• Develop production and inspection specifications.

• Planned applications on core components (preliminarily classified as SR)

• Load pads, inlet nozzles, seal rings

• Compressive assemblies, control rod assemblies, lead test pin receptacle

• Potential additional SSCs (longer-lived)

• PSP and fuel handling bearings, in-vessel storage racks

• PSP, fuel handling and reactor head sealing, sliding, and wear surfaces 5

NRC Staff Review of Coatings R&D

• R&D plan addresses key qualification parameters

• Coatings of core components are considered SR in preliminary design but may change in final design

• Assurance level expected at the OL stage will depend on coating function, failure consequences, and service conditions

• For environmental effects, testing plan is reasonable to characterize separate effects

• Combined environmental effects create more uncertainty in coating performance

• For potential ex-core applications on long-lived components, longer operating times in safety-significant functions make combined effects more important to consider

• Staff will consider the planned operating life and service conditions, along with coating function and consequence of failure, in its OL review of coatings

• Staff determined that the coating R&D activities are reasonably designed to address safety questions associated with the use of these coatings 6

Acronyms 7

• ACRS - Advisory Committee on Reactor Safeguards

• CP - Construction Permit

• CPA - Construction Permit Application

• DANU - Division of Advanced Reactors and Non-power Production and Utilization Facilities

• GSA - General Services Administration

• IHT - Intermediate Heat Transport System

• LWR - Light Water Reactor

• NASA - National Aeronautics and Space Administration

• NRC - Nuclear Regulatory Commission

• NRR - Office of Nuclear Reactor Regulation

• OL - Operating License

• PSAR - Preliminary Safety Analysis Report

• R&D - Research and Development

• RAC - Reactor Air Cooling System

• RV - Reactor Vessel

• SSC - Structures, Systems, and Components

• TRL - Technology Readiness Level