Assessment of Windbreaks as a Dust Control Strategy for Communities in Arid Climates Such as the Us-mexico Border Region

NARRATIVE SUMMARY Dust generated from the mechanical disturbance of granular material is known as " fugitive dust " since it is not released into the atmosphere in a restricted flow stream such as an exhaust pipe or smoke stack. Fugitive dust includes dust from unpaved roads, disturbed land in developed areas, agriculture, and undeveloped grazing land. Wind-blown and vehicle generated fugitive dust are air quality and health concerns in many areas along the U.S.-Mexican border. Fugitive dust contains particulate mater (PM) smaller than 10µm (PM10). PM10 has been linked with numerous health problems. Air quality officials in the southwest are dissatisfied with the available options for controlling vehicle generated fugitive dust since water-based treatments are often impractical in arid climates. Previous SCERP-funded studies in Doña Ana County, New Mexico have examined the hypothesis that dust traveling near the ground is redeposited when it encounters brush, fences, and small terrain irregularities. A conclusion from this previous work was that atmospheric stability, time of day, surface roughness and nearby vegetation are important factors affecting the amount of vehicle-suspended dust that is actually transported a sufficient distance to affect local and regional air quality. Other field studies have supported this conclusion. The objective of the current project was to build on previous SCERP and related research to better understand dispersion of fugitive dust in the presence of vegetation when atmospheric conditions transition from unstable to stable conditions in the border desert environment. The second objective of this project has been to develop a computer model of the transport of vehicle generated fugitive dust. The modeling tool that has been developed is capable of reproducing important aspects of the field experiment from this project and other work. The model is particularly useful to planners and decision makers as it can provide estimates of the benefits that vegetation can provide for reducing fugitive dust under various atmospheric conditions. INTRODUCTION Dust generated from the mechanical disturbance of granular material is known as " fugitive dust " since it is not released into the atmosphere in a restricted flow stream. Fugitive dust includes dust from unpaved roads, disturbed land in developed areas, agriculture, and undeveloped grazing land. Wind-blown and vehicle generated fugitive dust is an air quality and health concern in many areas along the U.S.-Mexican border. Fugitive dust contains particulate mater (PM) smaller than 10µm (PM10). PM10 has been linked with numerous health problems. Illnesses can …