NuScale US460 Standard Design Approval Application Review

image of NuScale US460 Standard Design Approval Application Review
Who:   NuScale Power, LLC (NuScale)
What:   Application for a Standard Design Approval for a small modular reactor (US460)
When:   By letter dated December 31, 2022 (electronically submitted on January 1, 2023), NuScale completed its staged SDA application submittal.

On this page:

Project Overview

The staff of the U.S. Nuclear Regulatory Commission (NRC) is currently engaged in review activities of NuScale’s US460 Standard Design Approval (SDA) for a light water technology small modular reactor. (DOCKET NOs. 05200050 and 99902078)

Plant Characteristic Description
Reactor Type Light water small modular reactor
Power per module 77 MWe per nuclear power module (NPM)
Number of NPMs 6
US460 SDA Total Power 462 MWe

For additional detail, see the following related page:

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Project Status

The NuScale US 460 SDA application (SDAA) review status is displayed in the dashboard below. Specifically, the dashboard contains the high-level tasks and review plan. It allows the user to use various filters and visualizations in the Microsoft® Power BI® software platform to investigate the overall trends regarding:

  • Phase A Review Progress
  • NuScale SDA Application Review Timeline
  • Status of Requests for Additional Information (RAIs)
  • Status of High Impact Technical Issues (HITIs)

As the review progresses, the dashboard will be updated to reflect new information.


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Project Details

The SDAA review is broken up into the following phases:

  • Phase A (timeline based on categorization by chapter described below): The NRC staff performs audit (minimize/eliminate need for Requests for Additional Information (RAIs)), establish RAI deadline based on phase milestone, and Safety Evaluation Report (SER) development.
  • Phase B (3 months): SER review by the technical editing services, the Office of the General Counsel review, and a complete director concurrence on the Advanced Safety Evaluation Report (ASER).
  • Phase C (2 months): Advisory Committee on Reactor Safeguards review of the ASER.
  • Phase D (2 months):
    • 1st Month – The Project Manager will coordinate an SER final concurrence with applicable Division Directors (specifically divisions impacting SER development). The ASER Chapters 1 through 19 will not move forward as an FSER until all interdependencies are satisfied. NOTE: Topical Reports (TRs) are stand-alone and require stand-alone concurrences, but select chapters are still dependent on select TRs. The Technical Adviser and Division Directors will also be reviewing TRs when concurrences are made.
    • 2nd Month – All chapters will be processed into a Final Safety Evaluation Report (FSER).

As described above, each chapter is designated a categorization based on the level-of-effort required to perform the review. These categorizations and nominal timelines for Phase A are the following (NOTE: some subsections in some chapters may be a higher categorization):

  • Low effort chapters: 8-month review timeline
  • Medium effort chapters: 12-month review timeline
  • High effort chapters: 16-month review timeline

Additionally, during the SDAA readiness assessment and subsequent acceptance review, the NRC staff worked with NuScale and identified several High Impact Technical Issues (HITIs) related to the SDAA that will likely require increased focus by NuScale and the NRC staff to ensure timely completion of the safety review. The specific issues identified are outlined in the dashboard above.

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Contacts for the NuScale US460 SDA application review
Lead Project Manager Getachew Tesfaye
Public Affairs Officer Scott Burnell

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