01661742

Component

State Departments of Transportation (DOT) are required to undertake quantitative mobile source air toxics (MSAT) analyses under the National Environmental Policy Act (NEPA) for certain projects. Over the past 10 years, transportation practitioners in Texas and other states have been using link-based volume change (of greater than ±five percent) between design-year build and a no-build alternative. This is used as the criteria for identifying the affected network for a MSAT analysis. This method is difficult to automate and resource intensive. It is prone to human error because it relies on manual processes. Therefore, there is a need for an alternative process that provides consistency, can be automated, improves efficiency, and saves taxpayer dollars. In this study, a state of the practice review was performed, covering the history of federal regulations and requirements pertaining to quantitative MSAT analysis. The research team reviewed how other state DOTs have implemented various methods to meet quantitative MSAT analysis requirements under NEPA. The study also investigated current Federal Highway Administration (FHWA) recommended methods. Finally, the study compares the current methods with distance- and travel time-based alternative methods to identify the affected transportation network for MSAT analysis using case studies in the Dallas-Fort Worth Area. Although the focus of the study was to assist the Texas Department of Transportation (TxDOT), results from the study are transferrable and could benefit other states.

This paper was sponsored by TRB committee ADC10 Standing Committee on Environmental Analysis in Transportation. Alternate title: Identifying the Affected Transportation Environment for Mobile Source Air Toxic Analysis in National Environmental Policy Act Documents

18-05357

English

0000-0002-3141-1377

22p

2018

Transportation Research Board 97th Annual Meeting

Digital/other

Figures; Maps; References; Tables

Air quality; Alternatives analysis; Case studies; Environmental impact analysis; Environmental policy; Federal laws; Literature reviews; Mobile sources; Policy analysis; Pollutants; Regulations; State departments of transportation; State of the practice

Mobile Source Air Toxics; National Environmental Policy Act; Texas Department of Transportation; U.S. Federal Highway Administration

Dallas-Fort Worth

Environment; Highways; Planning and Forecasting; Policy

Transportation Research Board Annual Meeting 2018 Paper #18-05357

TRIS, TRB, ATRI

Jan 8 2018 11:21AM