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Tribal Air Emission Inventories

Creating an emission inventory is a process in which air quality managers collect information on the emissions for particular pollution sources within a specific area, such as a reservation, to use in making planning and policy decisions.  An emission inventory can help a tribe understand air quality on its lands and whether an air pollution control program is needed.  It is important to note that an emission inventory serves a different purpose than air quality monitoring. An emission inventory tells a tribe what sources are emitting which pollutants into the air. Air quality monitoring samples the air to measure which pollutants are present and in what amounts, but does not tell where the pollutants are coming from. A tribal emission inventory can include information about criteria air pollutants, hazardous air pollutants, major and minor point sources, area sources, and mobile sources. These documents provide guidance to tribes and EPA Regional Offices on how to create emission inventories. 

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