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Low-Level Waste and Decommissioning Sub-Arena

Low-level waste and decommissioning comprise one of three sub-arenas that the staff of the U.S. Nuclear Regulatory Commission (NRC) identified in considering which areas of the waste management arena to target for greater use of risk information. This page summarizes the following aspects of this sub-arena:


Facilitate the application of risk-informed and performance-based approaches in implementing the NRC's rulemaking, licensing, and oversight functions for low-level waste, including waste incidental to reprocessing, and decommissioning on a case-by-case basis.

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The NRC staff engages with the agency's licensees and stakeholders (including the public) in making significant decommissioning decisions and implementing significant actions focusing on risk-significance and potential environmental impacts. The NRC's Office of Nuclear Material Safety and Safeguards (NMSS), in coordination with the Office of Nuclear Regulatory Research (RES) and the Center for Nuclear Waste Regulatory Analysis (CNWRA), is continuing development, maintenance, and evaluation of probabilistic environmental models and codes for risk/dose analysis. Use of probabilistic distributions as inputs to uncertain physical and behavior parameters is common in independent staff reviews in determining risk-significance and request for additional information development. The NRC also uses probabilistic tools with uncertainty analysis to review and assess dose impacts to demonstrate compliance with the dose criteria set forth in Subpart E of 10 CFR Part 20.

In review of waste determinations to be made by the U.S. Department of Energy that waste is incidental to reprocessing, the staff utilizes risk-informed performance-based approaches including uncertainty/sensitivity analyses and alternate conceptual models. The risk insights gained during the review are utilized to establish the monitoring areas for a site.

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

  • Continue to evaluate current dose modeling approaches for low-level waste and decommissioning, and provide recommendations for a path-forward to enhance the use of risk-informed and performance-based approaches in licensing reviews and regulatory implementation.
  • Continue making incremental improvement (as practicable) in rulemaking and guidance development, licensing, and oversight, to enhance the use of risk-informed and performance-based approaches.
  • Encourage the industry and NRC licensees to use a risk-informed and performance-based approach in demonstrating compliance with the NRC's risk/dose criteria.

Risk-Informed and Performance-Based Activities

The following table specifies 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 Low-Level Waste and Decommissioning Sub-Arena within the Waste Management Arena.

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Initiative, Program or Project Project Description and Major Activities Status
Part 61 Revisions: Require Site-Specific Analysis for disposal of Unique Waste Streams Conduct Rulemaking to require Site-specific Analysis for licensed low-level waste disposal facilities. The Commission was provided a draft rulemaking and guidance document in July 2013. In its February 12, 2014, SRM-SECY-13-0075, the Commission approved publication of the proposed rule and the associated draft guidance for public comment, subject to the comments and changes noted in the SRM. The NRC staff is currently revising the proposed rule and associated draft guidance.
Risk Basis: This rule improves on the risk-informed, performance-based framework already present in Part 61 to ensure that the safety analyses performed to evaluate long-term isolation are comprehensive and consistent.
More Information from Topic Web Site
Part 61 Implementation: Update Branch Technical Position (BTP) on Concentration Averaging and Encapsulation Risk-inform, performance-base positions in this BTP. It was published draft for comment in 2012. The final version will be issued in late 2014.
Risk Basis:The revised guidance provides additional means for licensed facilities to reduce worker exposure and include risk based approaches that provide measures to improve the process for the use of site- and waste-specific averaging approaches.

To request additional information, Contact Us About Risk-Informed, Performance-Based Regulation.

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Page Last Reviewed/Updated Wednesday, April 29, 2015