Tightening the Screws – Lower NAAQS Mean Higher Costs
Posted: April 20th, 2010
ALL4’s Ambient Group continues to track and provide you with updates on the latest developments related to National Ambient Air Quality Standards (NAAQS). The NAAQS are the primary basis for the permitting of new stationary sources and modifications to stationary sources in the United States. A region’s compliance status with the NAAQS dictates how new major stationary sources and modifications to existing major stationary sources are permitted via the New Source Review (NSR) process (i.e., Prevention of Significant Deterioration (PSD) or Nonattainment New Source Review (NNSR)). Lowered NAAQS become increasingly important during the PSD process since the new, extremely stringent NAAQS levels tend to influence the level of control required for a given project and could ultimately doom an otherwise environmentally beneficial and technically sound project. The following reduced NAAQS levels are, or will be, relatively new to the air quality permitting process:
- PM2.5 (Annual and 24-hour NAAQS evaluated in 2006)
- NO2 (New 1-hour NAAQS that became effective on April 12, 2010)
- SO2 (New 1-hour NAAQS scheduled to become effective in June 2010)

