#FFFFFF
Current air quality permit modeling guidance for estimating impacts from stationary sources of air pollution.
#FFFFFF
- General Permitting Questions
- Colorado Modeling Guidance for Air Quality Permits
- Supplemental Modeling Guidance, Forms, and Information
- Meteorological & Geophysical Data for Air Quality Permit Modeling
- Maps, Class I Receptors, Figures, Tables for Air Quality Permit Modeling
- Elevation Data Quad Download Tool
- Federal Modeling Support
- Online Training
#FFFFFF
General Permitting Questions
- For general permitting questions, contact the Stationary Sources Program. Contact the Permit Modeling Unit at cdphe_apcd_modelingdeterminations@state.co.us for modeling questions and determinations.
- Modeling Procedure Guidance. Please see this document for guidance on how to request modeling files and general permit modeling questions.
- Completeness Checklist for Modeling Submittals
- FAQs on Air Quality Modeling Data and Techniques (PDF)
#FFFFFF
Colorado Modeling Guidance for Air Quality Permits
- Colorado Modeling Guideline for Air Quality Permits (May 2022)
- Meteorological Determinations and Application of Dispersion Models
- Modeling Determinations.
- If an applicant is unsure if modeling will be required to conduct a required NAAQS analysis, the APCD-114 Form should be filled out to obtain a decision prior to submitting a permit application or a modeling demonstration to the Air Pollution Control Division (APCD). Form Instructions are provided here.
- Once a determination is made, the applicant will be provided documentation of the Modeling Determination by APCD. The APCD-114 Form and Determination will be part of the source or modification's permit application record. If a determination of "Modeling Required" is made, the applicant must submit a modeling analysis demonstrating compliance with the NAAQS with the permit application. If a determination of “Modeling Not Required” is made, the completed APCD-114 Form and Determination will be included as part of the source or modification’s permit application record and no further analysis will be required.
#FFFFFF
Supplemental Modeling Guidance, Forms, and Information
- Air Pollution Emission Notice (APEN) and application forms.
- Checklist for Non-PSD Sources/Modifications (e.g., minor sources) (March 2002) (PDF)
- Background concentration form (April 17, 2012) (spreadsheet)
- Third Party Modeling Review (SB11 - 235) request procedur (PDF) - This option may be available for minor source permitting actions if a modeling review backlog exists.
- Checklist for Modeling Protocol (June 17, 1997) (PDF)
- Database of "scenic and/or important views" (March 11, 2005) (PDF)
- Prevention of Significant Deterioration (PSD) Increment Tracking (February 26, 2001; updated 12/28/05)
- Air Quality Control Commission regulations
#FFFFFF
Meteorological & Geophysical Data for Air Quality Permit Modeling
- The Technical Services Program of the Air Pollution Control Division has data from current and historic meteorological towers in Colorado that are suitable for use in regulatory models. Contact the Division at cdphe_apcd_modeling_files@state.co.us for data. Division approval should be obtained on a case-by-case basis before meteorological datasets are used for regulatory (e.g., air permit) modeling.
#FFFFFF
Maps, Class I Receptors, Figures, Tables for Air Quality Permit Modeling
- Colorado PSD baseline areas and minor source baseline dates. (PDF)
- Nonattainment/Maintenance Area Boundaries (interactive map)
- Federal Class I Areas (interactive map)
- Federal Class I Areas (Figure 4 from Colorado Modeling Guideline) (image)
- Class II areas with the protection of Class I increments for sulfur dioxide (Figure 3 from Colorado Modeling Guideline) (image)
- Flowchart of permit review process from a modeling perspective (Figure 5 from Colorado Modeling Guideline) (image)
- Diagram of roles and responsibilities in the modeling review process for construction permits (Figure 6 from Colorado Modeling Guideline) (image)
#FFFFFF
Federal Modeling Support
- U.S. EPA
- U.S. EPA State Guidance
- Support Center for Regulatory Atmospheric Modeling (SCRAM) - EPA guidance, models, user's guides, and related information.
- The primary EPA modeling guideline is Appendix W to 40 CFR Part 51. (PFD)
- Technology Transfer Network (TTNWeb) - a collection of related Web sites containing information about many areas of air pollution science, technology, regulation, measurement, and prevention.
- New Source Review (NSR)
- OAQPS Air Quality Modeling - topics and areas associated with air quality modeling.
- Federal Land Managers
#FFFFFF