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science   BRIEF
BUILDING A SCIENTIFIC FOUNDATION FOR SOUND ENVIRONMENTAL DECISIONS
                         EPA Near Roadway Field Study, Las Vegas
     EPA scientists and engineers will measure, define,
     and profile roadway air pollutants along a portion of
     U.S. Interstate 15 in Las Vegas beginning in
     December 2008.

     During the year-long study, EPA researchers will
     work with the Federal Highway Administration
     (FHWA) to gather information to better understand
     the relationship between traffic emissions and
     roadway-related air pollution concentrations at
     various distances from the roadway. Study results
     will be used to inform future research such as air-
     quality modeling, health studies, and evaluations of
     risk-management alternatives.

     The Las Vegas study is part of an EPA/FHWA joint
     program formally called the National Near
     Roadway Mobile Source Air Toxics (MSAT)
     Study — a project focused on providing the scientific
     knowledge and understanding needed to identify the
     most effective strategies and tools to control exposure
     to air pollution, including natural and man-made
     mitigation strategies to protect people who live, work
     or go to school nearby (e.g., placement of vegetation
     or man-made barriers near roadways).
                              During the study, EPA will gather data by placing
                              instruments 10, 100, and 350 meters from U.S.
                              Interstate 15 near Dean Martin Drive and 100 meters
                              from West Post Road. Researchers will also measure
                              meteorological conditions and roadway
                              characteristics such as traffic counts and vehicle
                              types.

                              Previous research by EPA and others has found that
                              concentrations of particles and gases associated with
                              motor vehicles are elevated near major roadways and
                              other major transportation sources such as airports.
                              Elevated concentrations of particles and gases emitted
                              from vehicle tailpipes, road dust from passing
                              vehicles, and particles from brake and tire wear have
                              also been found near major transportation sources.

                              Specific gases found in higher concentrations near
                              roadways include carbon monoxide, oxides of
                              nitrogen, and air toxics including benzene and
                              toluene.

                              The Las Vegas study is the first in a series of studies
                              planned in the United States with different road
                              conditions and weather patterns.

                              EPA Technical Contact: Dan Costa, Sc.D., National
                              Program Director for the Clean Air Program,
                              919-541-2532 or costa.dan@epa.gov
                              EPA Media Contact: Margot Perez-Sullivan, Public
                              Information Officer, 415-947-4149 or
                              perezsullivan. margot@epa.gov
                              FHWA Media Contact: Doug Hecox
                              Public Affairs Specialist
                              (202) 366-2244 ordhecox@dot.gov
     U.S. Environmental Protection Agency
     Office of Research and Development

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