are important tools, enabling us to better comprehend the types and quantities
of pollutants that are emitted to the air we breathe over a specific time
period. In order for the Air Division to create these inventories,
it is necessary to have:
Established the identities of important
Knowledge of what pollutants
are emitted from these sources
Access to high quality source-specific
emission factors (EFs), as often can be found in EPA's AP-42
document series or Emission
Inventory Improvement Program (EIIP). (for example: lbs
of benzene emitted per mile traveled by a vehicle, or lbs of carbon
monoxide emitted per ton of wood burned).
An estimate of "activity"
(for example: how many miles were traveled by the vehicle in
a given year, or how many tons of wood were burned in a given year)
In general, "sources"
fall into one of the following categories:
Refers to emissions that can be traced to a specific concentrated
point (such as a factory, power plant, hospital, etc.) This
category is extensively inventoried through the Air Division's annual
Point Source Registration Program.
According to U.S. EPA definition, however, most of Vermont's "Point
Sources" would be considered "Area Sources" for annual
emissions of certain pollutants. For example, if potential emissions
from a particular factory are less than the defined threshold, it
will be classified as an Area Source. For more information,
please reference Table 1 of EPA's Consolidated
Emissions Reporting Rule (CERR) published in the Federal Register.
Stationary sources of air pollution for which it is difficult to attribute
emissions to a concentrated point (such as emissions from livestock,
open burning of trash, residential woodstoves, etc.). In some
cases, this category may include "Point Sources" having
emissions below a certain defined threshold. (see Point above)
Includes both Onroad (automobiles, trucks, buses, motorcycles, etc)
and Nonroad (construction equipment, lawnmowers, snowmobiles, motorboats,
Natural sources of air pollution (ex: Isoprene emitted from
plants, Ammonia emitted from the soil, etc.)
here to view information regarding Historical Air Emissions
inventories compiled by the Air Division.
Questions or comments? - contact Jeff