Quantitative Mobile Source Air Toxics Analysis for a Hypothetical Transportation Project

This paper demonstrates an approach to quantitatively analyze emissions of mobile source air toxics (MSAT) from transportation projects. It is intended as a resource for project sponsors, documenting methodology and assumptions that sponsors can use when estimating MSAT emissions. The paper examines a hypothetical project involving widening of a 10-mile stretch of urban freeway. The project boundaries include interchange ramps and segments of connecting arterials for six interchanges. The project analysis includes consideration of how the project affects roadway volumes and congested speeds. MSAT emissions associated with the hypothetical roadways are modeled using the U.S. Environmental Protection Agency (EPA) MOVES2014a software. Emissions are compared between several alternatives and timeframes, and for different volumes of truck traffic. The analysis shows that MSAT emissions decline substantially from a base year of 2015 to a design year of 2040. Emissions do vary somewhat between alternatives, with a widened and lower congestion freeway producing lower emissions than a no build alternative. In this project example, the emission benefits of reducing congestion outweigh the negative emission impacts of higher demand, although this may vary for other projects. Emissions vary far more heavily by year than by alternative. Emissions of most of the MSAT pollutants follow this pattern.

• Record URL:
  https://www.fhwa.dot.gov/environment/air_quality/air_toxics/research_and_analysis/msat_hypothetical/fhwahep17049.pdf
• 
• Corporate Authors:

  Cambridge Systematics, Incorporated

  150 Cambridge Park Drive, Suite 4000
  Cambridge, MA  United States  02140-2369

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Porter, C D
  • Grose, T
  • Kall, D
  • Martinez, V
• Publication Date: 2017-3

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 32p

Subject/Index Terms

• TRT Terms: Alternatives analysis; Analysis; Construction projects; Estimating; Methodology; Pollutants; Traffic congestion
• Identifier Terms: Motor Vehicle Emission Simulator (MOVES)
• Subject Areas: Environment; Planning and Forecasting; Transportation (General);

Filing Info

• Accession Number: 01637748
• Record Type: Publication
• Report/Paper Numbers: FHWA-HEP-17-049
• Contract Numbers: DTFH61-11-D-00030 Task 5011
• Files: TRIS, ATRI, USDOT
• Created Date: Jun 5 2017 11:45AM