Project proponents submit a PSD permit application to the permitting authority. Within 30 days of receipt applications are sent to the National Park Service (NPS) Air Resources Division for review if they “may affect” air quality or air quality related values (AQRVs) in a Class I area. PSD permit applicants must use the best available control technology for all pollutants emitted in "significant" amounts, and demonstrate that their emissions will not cause a violation of the national ambient air quality standards or a PSD increment.
The PSD permit review process for the NPS and other federal land managers consists of three main analyses:
- a best available control technology (BACT) analysis to ensure that the emission increases from the proposed facility are minimized;
- an air quality analysis to ensure that the pollutant levels do not exceed national ambient air quality standards and PSD increments; and
- an air quality related values (AQRV) analysis to ensure that the Class I area resources are not adversely affected by the proposed emissions.
Modeling software is used to predict how much emissions from the new facility will reach affected parks. Cumulative emissions from other sites as well as from the proposed facility are considered in making the final impact determination for the park or wilderness. If this "loading" reaches a level that negatively affects resources or visibility in the park, then an "adverse impact determination" may be made in these cases. In such cases, the NPS may recommend that the state deny the permit application. Compromises are always explored and the NPS seeks to recommend solutions to reduce or control emissions so that park resources will not be significantly affected.
Visit the Resources for Permit Applicants page to learn more.