Publisher's Synopsis
This technical resource document describes several methods for preparing a site-specific risk assessment for a source (i.e., a single emission point within one facility), a group of sources (i.e., multiple emission points within one facility), or a group of similar facilities (e.g., within the same source category) that emit(s) toxic air pollutants. Air toxics may be emitted from power plants, factories, cars and trucks, and common household products. Sources that stay in one place are referred to as stationary sources. Vehicles and other moving sources of air pollutants are called mobile sources. This technical resource document is intended for assessing risks associated with stationary sources of air toxics. While its primary focus is on Hazardous Air Pollutants (HAPs), this resource document can be applied to all air pollutants (with the exception of criteria air pollutants, which are assessed using different tools and methods). This technical resource document is the second of a three-volume set. Volume 1: Technical Resource Manual discusses the overall air toxics risk assessment process and the basic technical tools needed to perform these analyses. The manual addresses both human health and ecological analyses. It also provides a basic overview of the process of managing and communicating risk assessment results. Other evaluations (such as the public health assessment process) are described to give assessors, risk managers, and other stakeholders a more holistic understanding of the many issues that may come into play when evaluating the potential impact of air toxics on human health and the environment. Readers with a limited understanding of risk assessment are encouraged to consult Volume 1. Volume 2: Facility-Specific Assessment (this volume) builds on the technical tools described in Volume 1 by providing an example set of tools and procedures that can be used for source-specific or facility-specific risk assessments. Information is also provided on tiered approaches to source- or facility-specific risk analysis. Volume 3: Community-Level Assessment builds on the information presented in Volume 1 to describe to communities how they can evaluate and reduce air toxics risks at the local level. The volume will include information on screening level and more detailed analytical approaches, how to balance the need for assessment versus the need for action, and how to identify and prioritize risk reduction options and measure success. Since community concerns and issues are often not related solely to air toxics, the document will also present readily available information on additional multimedia risk factors that may affect communities and strategies to reduce those risks. The document will provide additional, focused information on stakeholder involvement, communicating information in a community-based setting, and resources and methodologies that may play a role in the overall process. Note that EPA's Office of Pollution Prevention and Toxics has also developed a Community Air Screening How To Manual that will be available in 2004 and will be discussed in Volume 3.
