|As the principle component of the Great Lakes Regional Air Toxic Emissions Inventory project,
the Regional Air Pollutant Inventory Development System (RAPIDS) is the first ever multi-jurisdictional
pollutant emissions inventory software that has been developed. This software is an important product of
the binational steering committee effort to design and implement a regional inventory containing sources
of toxic air contaminants. RAPIDS was originally tested by Illinois, Indiana, and Wisconsin in their joint
development of the Southwest Lake Michigan Pilot Study. The focus of the study was on the Commission defined list of 49 toxic pollutants, in addition to several other important nontoxic compounds. Over the years RAPIDS has been used by each Great Lakes state and province of Ontario to inventory over 200 toxic contaminants.