Sec. 212-1.3. Determination of environmental rating

In accordance with the applicability requirements of section 212-1.1 of this Part, the department will assign an environmental rating for each air contaminant emitted from each process emission source or emission point in accordance with subdivisions (a) through (e) of this section. The factors in subdivisions (a) through (d) will be considered in making a determination of the environmental rating to be applied to an air contaminant pursuant to subdivision (e), Table 1 – Environmental Rating Criteria of this section.

(a) toxic and other properties and emission rate potential of the air contaminant;

(b) location of the process emission source or emission point(s) for the air contaminant with respect to residences or other sensitive environmental receptors, taking into account the area’s anticipated growth;

(c) emission dispersion characteristics at or near the process emission source or emission point(s), taking into account the physical location of the process emission source or emission point(s) relative to the surrounding buildings and terrain; and

(d) the projected maximum cumulative impact of an air contaminant taking into account emissions from all process emission sources at the facility under review and the pre-existing ambient concentration of the air contaminant under review.

(e) Table 1 - Environmental rating criteria.

Rating	Criteria
A	An air contaminant whose discharge results, or may result, in serious adverse effects on receptors or the environment. These effects may be of a health, economic or aesthetic nature or any combination of these.
B	An air contaminant whose discharge results, or may result in only moderate and essentially localized effects; or where the multiplicity of sources of the contaminant in any given area require an overall reduction of the atmospheric burden of that contaminant.
C	An air contaminant whose discharge may result in localized adverse effects of an aesthetic or nuisance nature.
D	An air contaminant whose discharge will not result in measurable or observable effects on receptors, nor add to an existing or predictable atmospheric burden of that contaminant which may cause adverse effects, considering properties and concentrations of the emissions, isolated conditions, stack height, and other factors.