Criteria for Development of Evacuation Time Estimate Studies (NUREG/CR-7002, Revision 1)

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Publication Information

Manuscript Completed: November 2020
Date Published: February 2021

Prepared by:
T. Smith

Office of Nuclear Security and Incident Response
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

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The evacuation time estimate (ETE) is a calculation of the time to evacuate the plume exposure pathway emergency planning zone (EPZ). An EPZ is the area around a nuclear power plant for which planning is needed to ensure that prompt and effective actions can be taken in the event of a radiological accident. The EPZ is typically an area with a radius of about 10 miles (16 kilometers) around a large light-water reactor but may vary in extent based on the emergency planning needs for the facility type. The ETE is primarily used to inform protective action decision-making and may also be used to assist in developing traffic management plans to support an evacuation. The ETE should be developed to provide the time to evacuate 90 percent and 100 percent of the total population of the EPZ. The 90 percent ETE provides the time value that would typically be used to support protective action decisions.

This document provides guidance for the development of ETEs, including those associated with staged evacuations. The document also identifies the importance of using approved emergency response plans and existing traffic control information to reflect the expected response actions during an emergency. Guidance on the review and update of ETEs is also included. Revision 1 updates the guidance based on the study of ETEs in NUREG/CR-7269, “Enhancing Guidance for Evacuation Time Estimate Studies,” issued March 2020.

The revised guidance reflects the importance of various model parameters and identifies the measures of effectiveness useful for verifying adequate model performance. The format and guidance provided here will support consistent application of the ETE methodology and can serve as a template for the development of ETE studies. Applicants and licensees may propose an alternative method for complying with the associated portions of the emergency preparedness regulations, and the U.S. Nuclear Regulatory Commission would determine whether they have provided the basis for the findings required for the issuance or continuance of a permit or license.

Page Last Reviewed/Updated Wednesday, March 24, 2021