New Source Review

Assistance Document for Nonattainment Area New Source Review and Prevention of Significant Deterioration

Preliminary Draft February 1997

This document is the cumulative result of hours of preparation and review by numerous people within the Illinois Environmental Protection Agency (Illinois EPA). Although, it was a group effort by the entire Permit Section, the contributions by the following authors of the principal chapters is gratefully acknowledged:

Part I:Frequently Asked QuestionsJim RossPermit Section
Part II:Flow chartsBob SmetPermit Section
Part III:ExamplesJoy MajumderPermit Section

Finally, the tedious task of reviewing drafts and suggesting improvements to this guidance was conducted with particular concern and dedication by the New Source Review Manager Chris Romaine. A special note of thanks is extended to those individuals.

Donald E. Sutton
Permit Section Manager

Table of Contents


  • Guidance Organization
  • Introduction and Overview

Part I - NSR Q & A

Answers to Frequently Asked Questions Regarding NSR and PSD

  1. What is New Source Review?
  2. What is PSD?
  3. What are some of the differences between nonattainment NSR and PSD?
  4. What is a "netting exercise"?
  5. How do you determine the contemporaneous time frame for netting?
  6. What are contemporaneous emission decreases and when are they needed?
  7. What are emission offsets and when are they needed?
  8. What is the difference between BACT and LAER?
  9. Do I include fugitive emissions when determining the emissions change from proposed project?
  10. What is the correct way to classify or refer to different changes at a source?
  11. For the Chicago ozone nonattainment area, what constitutes a new major source or major modification?
  12. Can a source be subject to nonattainment NSR and PSD both?
  13. What is a "Sham" permit?
  14. What is "debottlenecking"?
  15. What does "relied on" mean in regards to creditable emissions increases and decreases in a netting exercise and what are it's implications?
  16. What do the terms "synthetic minor" and "natural minor" generally mean?
  17. What is a PSD increment?
  18. When is a netting exercise required for PSD and nonattainment NSR?
  19. What criteria do you use to determine if two plants which are close by and related should be treated as the same source or separate sources for purposes of NSR?
  20. Does one ever need to go beyond the contemporaneous time period to consider past emissions increases?

Part II - Flow Charts

  • Flow Chart 1 - Source Type/Applicability Determination
  • Flow Chart 2 - Proposed Source
  • Flow Chart 3 - Nonattainment NSR
  • Flow Chart 4 - PSD Determination - Attainment Area
  • Flow Chart 5 - Net Emissions Increase
  • Flow Chart 6 - Contemporaneous Period Determination

Part III: Examples

  • Example 1: Project is neither Major nor Major Modification
  • Netting Exercise - Example 1
  • Example 2: Project is neither Major nor Major Modification
  • Example 3: Proposed Project itself is not Major but constitutes a Major Modification
  • Example 4: Proposed Project itself is Major but not a Major Modification
  • Netting Exercise - Example 4
  • An Example of Compliance by existing source
  • Certification of Compliance
  • An example of Analysis of alternative
  • Analysis of Alternatives