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page title goes here Risk Assessment

PRG User's Guide

PDF of User's Guide.

Welcome to the EPA's "Preliminary Remediation Goals for Radionuclides at Superfund Sites" (PRG) user's guide. Here you will find descriptions, equations, and default exposure parameters used to calculate the risk-based PRGs. If this is your first time using the PRG Calculator, it is strongly recommended that you first read "Radiation Risk Assessment At CERCLA Sites: Q & A". 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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1. Introduction

2. Understanding the PRG Website

3. Understanding Your Superfund Site

4. Land Use Descriptions, Equations, and Technical Documentation

5. Recommended Default Exposure Parameters

6. References