United States Nuclear Regulatory Commission - Protecting People and the Environment

Fuel Cycle Sub-Arena

The Nation's fuel cycle facilities comprise one of two sub-arenas that the staff of the U.S. Nuclear Regulatory Commission (NRC) identified in considering which areas of the materials safety arena to target for greater use of risk information. This page summarizes the following aspects of this sub-arena:

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For fuel cycle facilities, make continuous improvement in licensing and oversight, and risk inform new regulations as needed, while performing existing risk-informed functions.

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SECY-99-100 and SECY-04-0182, as well as the related staff requirements memorandum (SRM), provide the conceptual framework for risk-informing the NRC's fuel cycle activities. Guidance on how to apply this framework is provided in "Risk-Informed Decision-Making for Material and Waste Applications, Rev. 1," which is available in the NRC's Agencywide Documents Access and Management System (ADAMS), under Accession No.ML080720238. In particular, individual risk-informed applications must meet the established screening criteria.

The screening criteria applied to the goals (below) of implementing the NRC's revised regulatory requirements, as specified in Title 10, Part 70, of the Code of Federal Regulations (10 CFR Part 70), would indicate that the given activity was undertaken to increase confidence in the margin of safety of fuel cycle facilities by requiring the use of a risk-informed approach to identify and manage items that are relied on for safety. Cost/benefit was not a consideration, and technical feasibility was known because two licensees had already implemented such systems. The revision of 10 CFR Part 70 is expected to reduce staff effort, while improving regulatory effectiveness, by providing more frequent updates of licensee design information and related risk information.

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The staff has established the following goals for risk-informed and performance-based activities in this sub-arena:

  • Revise the existing licensing guidance to reflect lessons learned from implementation of 10 CFR 70 Subpart H.
  • Complete revision of inspection guidance to make use of the resulting risk information to focus inspections.
  • Revise the Fuel Cycle Oversight Program to make it more risk-informed and performance-based consistent with Commission direction.

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List of Risk-Informed and Performance-Based Activities

This list shows the ongoing licensing initiatives, projects, and activities that the staff of the U.S. Nuclear Regulatory Commission (NRC) has targeted for greater use of risk information in the Fuel Cycle Facilities Sub-Arena within the Materials Safety Arena:

Implementation of Lessons Learned from Uranium Accumulation Event

Summary Description

In 2016 a fuel fabrication facility discovered a significant amount of uranium had accumulated within a process ventilation system that exceeded the system's criticality safety evaluation limits. Although a criticality did not occur, the event was considered significant. In addition to the expected regulatory response to the event (including an augmented inspection, confirmatory action letter, information notice, etc.), the staff initiated an effort to capture lessons from the event that could be used to improve the regulatory processes so that similar events are avoided or identified earlier.

FY 2017

In January 2017, the lessons-learned team issued a report that identified potential improvements in five regulatory process areas: license application review, inspection program, operating experience program, roles and responsibilities, and knowledge management. An action plan was developed to prioritized and further evaluate the potential improvements identified in the lessons-learned report. The activity is in the implementation phase for the recommended high-priority items.

Risk-Informed Basis

Many of the areas identified for potential improvement within the lessons-learned report relate to the consideration of, and technical bases for, the risk insights and significance derived from the licensee's analyses. The use of these insights can have a direct effect on the license review process and inspection program. There are also related potential improvements to the operating experience program (including reporting guidance), roles and responsibilities, and knowledge management.

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Rulemaking for Reprocessing Facilities

Summary Description

In SRM-SECY-13-0093, the Commission approved development of a reprocessing-specific rule in a new 10 CFR Part 7X. In the SRM the Commission also directed that the continued development of the regulatory framework for reprocessing be limited in scope, for the time being, to the resolution of "Safety and Risk Assessment Methodologies and Considerations for a Reprocessing Facility."

FY 2015

Process flow diagrams and facility descriptions were developed for a conceptual aqueous reprocessing facility, with associated event and fault trees for a hypothetical red-oil explosion. Preliminary best-estimate source term analyses were calculated and indicated a potential dose reduction of orders of magnitude, compared to the existing conservative approaches.

FY 2016

Mindful of limiting the scope of work as directed in SRM-SECY-13-0093, event and fault trees were developed for a hypothetical loss of cooling (LOC) accident to a concentrated high level waste storage tank. Preliminary quantification of the accident sequence was carried out using generic failure and probability data. Items Relied On For Safety (IROFS) were identified for both the hypothetical red-oil explosion and LOC accident sequences.

FY 2017

Work on the fuel reprocessing regulatory framework related to assessing the application of quantitative risk analysis (identified as Gap 5 in SECY-13-0093) was delayed during FY 2017 because of other higher priority activities.

Risk-Informed Basis

The purpose of this activity is to develop the foundation for the potential regulatory framework for reprocessing to enable a risk-informed licensing and oversight process by:

  • Evaluating methods for hazards and risk evaluations that can be implemented for aqueous and electrochemical reprocessing facilities;
  • Identifying performance requirements for a risk-informed regulatory framework; and
  • Obtaining peer review and public comments on the safety and risk assessment methodologies.

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Page Last Reviewed/Updated Wednesday, May 09, 2018