Cumulative air quality effects assessment

Abstract

Federal agencies in the United States are required to consider the cumulative effects (CEs) of their activities combined with those of others. This requirement has placed a burden on the environmental impact assessment (EIA) process due to the technical complexities involved with cumulative effects assessment (CEA). This article presents a CEA methodology that reduces some of the inherent complexities by focusing on the cumulative influence to a single environmental resource, ambient air quality. An eight-step method is presented herein as a tool for the assessment of cumulative air quality effects. Procedures for accomplishment of the more difficult steps, such as the determination of what activities to include in the evaluation and how to determine the significance of a cumulative effect, are also included.