Subchapter B Permits - Major Sources (cont'd)

Nonattainment New Source Review

Nonattainment NSR applies to major sources and major modifications in nonattainment areas. The nonattainment areas are not in compliance with the National Ambient Air Quality Standards (NAAQS) and are designated by the Environmental Protection Agency (EPA). The EPA has designated nonattainment counties in Texas for ozone, PM10, lead, and sulfur dioxide.

Nonattainment permitting is required if the source has emissions at or above the significant emission rates for the specific county designated as nonattainment.

To recap a previous example:

Nitrogen oxides (NOx) are a precursor for the criteria pollutant ozone. The significant emission rate for a NOx source to be considered major in a serious ozone nonattainment area is 50 tons per year. In addition, for a modification in a serious ozone nonattainment area to be major for NOx, the significant emission rate is 25 tons per year.

It is also important to note that emissions for all affected pollutants at a source located in a nonattainment area must be evaluated individually to determine if nonattainment permitting is required.

For example:

Volatile organic compounds (VOCs) and NOx are precursors for ozone. In ozone nonattainment areas, VOCs and NOx are evaluated to determine if a new major source is being constructed or if an existing major source is undergoing a major modification. Each ozone precursor is evaluated on its own merits, and these precursors are not reviewed in combination against the significant emission rates (i.e., NOx and VOC emissions are not added together for comparison against the significant emission rates).

Nonattainment permitting requires:

The tabbed information below contains more detail regarding nonattainment requirements.


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