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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 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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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