We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

To contact the EPA for questions about radiation risk assessment and/or this calculator, please Contact Us.

page title goes here Risk Assessment

A new Peak PRG output option has been added. Please see the What's New page for details.

PRG User's Guide

PDF of User's Guide.

Welcome to the EPA's "Preliminary Remediation Goals for Radionuclide Contaminants at Superfund Sites" (PRG) user's guide. Here you will find descriptions, equations and default exposure parameters used to calculate the risk-based PRGs. Additional guidance is also provided on sources of parameters and proper PRG use. It is suggested that users read the PRG FAQ page before proceeding. The user guide is extensive so please use the "Open All Sections" and "Close All Sections" links below as needed. Individual sections can be opened and closed by clicking on the section titles. Before proceeding through the user's guide please read the Disclaimer.

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Disclaimer

1. Introduction

2. Understanding the PRG Website

3. Using the PRG Table

4. Land Use Descriptions, Equations, and Technical Documentation

5. Recommended Default Exposure Parameters

6. References