Page 450 - Fundamentals of Air Pollution 3E

398 24. The U.S. Clean Air Act Amendments of 1990

TABLE 24-2
Classification and Attainment Dates for Ozone Nonattainment Areas
Classification Ozone design values Attainment deadline (from enactment)

Marginal 0.121 up to 0.138 ppm 1993 (3 years)
Moderate 0.138 up to 0.160 ppm 1996 (6 years)
Serious 0.160 up to 0.180 ppm 1999 (9 years)
Severe 0.180 up to 0.280 ppm 2005 (15 years)
Extreme 0.280 ppm and above 2010 (20 years)

sources with combined NO X and VOC emissions of 10 tons/year in their
control plans
As mentioned, nonattainment areas will have to implement different
control measures, depending on their classification. Marginal areas, for
example, are the closest to meeting the standard. They will be required to
conduct an inventory of their ozone-causing emissions and institute a per-
mit program. Nonattainment areas with more serious air quality problems
must implement various control measures. The worse the air quality, the
more controls areas will have to implement.
The new law also establishes similar programs for areas that do not
meet the federal health standards for the pollutants carbon monoxide and
particulate matter. Areas exceeding the standards for these pollutants will
be divided into "moderate" and "serious" classifications. Depending on
the degree to which they exceed the carbon monoxide standard, areas will
be required to implement programs introducing oxygenated fuels and/or
enhanced emission inspection programs, among other measures. De-
pending on their classification, areas exceeding the particulate matter stan-
dard will have to implement either Reasonably Available Control Technol-
ogy (RACT) or Best Available Control Technology (BACT), among other
requirements.

TABLE 24-3
Title I Emission Sources Requiring Control
EPA ozone Allowable emissions of
nonattainment NO, and VOC
classification combined (ton/year)
Extreme and severe 10
Serious 50
Moderate and marginal 100