text: Moreover, as its name indicates, the Prevention of Significant Deterioration statute is designed primarily to prevent ?deterioration? of an attainment area?s air quality. The relevant air quality standards that define whether an area is in attainment are the NAAQS. In a statute expressly linked to the NAAQS and designed to ensure that air quality does not ?deteriorate? with respect to the NAAQS, it is somewhat illogical to read the statute as requiring pre-construction permits simply because a facility may emit substances that will not affect attainment of the NAAQS. Under EPA?s approach, a facility could be covered by the permitting requirement even if it emits no NAAQS air pollutants at all. That, too, makes little sense and suggests that EPA has misread the statute.