Human Health Risk Assessment Protocol for Hazardous Waste Combustion Facilities
**Final September 2005**

Risk assessment is a science used to evaluate the carcinogenic risks and noncarcinogenic hazards to human health that are attributable to emissions from hazardous waste combustion units. These risk assessments include the evaluation of both direct and indirect risks. There is sufficient guidance available regarding the performance of direct inhalation risk assessments. On the other hand, indirect risk assessments are newer and more complex. As a result, this document describes the evaluation of direct inhalation risk, but primarily focuses on the procedures used to estimate risk resulting from indirect pathways.

This document is organized into nine chapters, three appendices, and a Region 6 Risk Management Addendum as follows:

Volume 1: Human Health Risk Assessment Protocol for Hazardous Waste Combustion Facilities

Volume 2 includes:
Appendix A: Chemical-specific Data and
Appendix B: Estimating Media Concentration Equations and Variable Values
Appendix C: Risk Characterization Equations

Methodology for Predicting Cattle Biotransfer Factors
Appendix A: Procedure for Extrapolating Steady State Concentrations
Appendix B: >Evaluation of the Molecular Connectivity Index [195 kb PDF]
Appendix C: Chemical Structures
Appendix D: Feeding Study Data as Reported
Appendix E: Normalized Beef and Milk Concentration Data
Appendix F: Data Review

U.S. EPA Response to Comments on the Human Health Risk Assessment Protocol for Hazardous Waste Combustion Facilities

Addendum: Region 6 Risk Management Addendum - Draft Human Health Risk Assessment Protocol for Hazardous Waste Combustion Facilities [41 kb PDF, 8/1998]

Download HHRAP Companion Database

The above files are in PDF Format.