i 

TABLE OF CONTENTS 

List of Figures .......................................................................................................................... iv 

List of Tables ........................................................................................................................viii 

PREFACE ....................................................................................................................... P-1 

ACKNOWLEDGEMENTS ................................................................................................................ P-3 

1.0 INTRODUCTION ....................................................................................................................1-1 

 1.1 Overview........................................................................................................................1-2 

 1.2. Objectives of These Guidelines....................................................................................1-2 

 1.3 Overview of Recommended BART Modeling Procedures........................................1-4 

 1.3.1 Three BART Modeling Approaches..................................................................1-4 

 1.3.2 Exemption Modeling ..........................................................................................1-5 

 1.3.3 Modeling the Effects of BART Controls on Visibility ....................................1-5 

 1.3.4 Modeling Protocols .............................................................................................1-6 

 1.4 Organization of this Document....................................................................................1-6 

2.0 BART MODELING REQUIREMENTS ................................................................................2-1 

 2.1 Regional Haze Rule and BART Guidelines ................................................................2-1 

 2.2 Role of Air Quality Models ..........................................................................................2-2 

 2.3 EPA Guidance on Air Quality Models........................................................................2-3 

 2.4 Steps in the BART Modeling Process..........................................................................2-4 

 2.5 CALPUFF Modeling Recommendations. ...................................................................2-6 

 2.6 Alternative Models for BART Analyses .....................................................................2-7 

 

3.0 CALPUFF FORMULATION AND IMPLEMENTATION ..................................................3-1 

 3.1 Original Model Development.......................................................................................3-1 

 3.2 CALPUFF Model Formulation....................................................................................3-2 

 3.2.1 Model Concept and Governing Equations........................................................3-2 

 3.2.2 Transport and Dispersion ..................................................................................3-3 

 3.2.3 Primary Particulates...........................................................................................3-4 

 3.2.4 Gas-Phase Chemistry..........................................................................................3-5 

 3.2.5 Aerosol Chemistry...............................................................................................3-6 

 3.2.6 Surface Removal ...............................................................................................3-10 

 3.3 CALMET Meteorological Preprocessor ...................................................................3-10 

 3.3.1 Boundary Layer Modules.................................................................................3-10 

 3.3.2 CALMET Diagnostic Wind Field Module......................................................3-11 

 3.4 Estimation of Regional Haze Contributions.............................................................3-12 

 3.4.1 CALPOST Methods..........................................................................................3-14 

 3.4.2 POSTUTIL ........................................................................................................3-15 

 3.4.3 Refined Extinction and Background Visibility Estimates.............................3-15 

 3.5 Model Availability.......................................................................................................3-16 

 3.6 CALPUFF Evaluation Studies...................................................................................3-16 

 

4.0 ALTERNATIVE MODELING ................................................................................................4-1 

 4.1 Overview .......................................................................................................................4-1 

 4.2 Available Alternative Models.......................................................................................4-4 
 

ii 

 4.3 Treatment of Sub-Grid-Scale Plumes .........................................................................4-6 

 4.3.1 CMAQ PinG ........................................................................................................4-7 

 4.3.2 CMAQ-APT-PM .................................................................................................4-7 

 4.3.3 CMAQ-MADRID-APT ......................................................................................4-8 

 4.3.4 CAMx PM IRON PiG........................................................................................4-8 

 4.3.5 CAMx Multi-Scale Flexi-Nesting......................................................................4-8 

 4.4 Steps in an Alternative Modeling Study .....................................................................4-9 

 4.5 Accuracy of Regional PM and Visibility Models .......................................................4-9 

 4.6 Data Base Requirements ............................................................................................4-12 

 4.7 Resource Requirements..............................................................................................4-12 

 4.7.1 Computers..........................................................................................................4-12 

 4.7.2 Staff Expertise ...................................................................................................4-13

 4.7.3 Schedule ............................................................................................................4-13 

 4.8 Approval Process for an Alternative Model.............................................................4-14 

 4.9 Cost of Alternative Modeling.....................................................................................4-15 

5.0 DATA BASES FOR CALPUFF MODELING........................................................................5-1 

 5.1. Development of CALMET Meteorological Files........................................................5-1 

 5.1.1 MM5 Data Sets....................................................................................................5-1 

 5.1.2 CALMET Model Configuration........................................................................5-2 

 5.1.3 MM5/CALMET Processing ...............................................................................5-5 

 5.1.4 Evaluation of the CALPUFF-Ready Meteorological Data Fields ..................5-6 

 5.1.5 Meteorological Data Archive and Distribution................................................5-8 

 5.2 Aerometric Monitoring Networks ..............................................................................5-8 

 

6.0 CALPUFF SCREENING APPLICATIONS..........................................................................6-1 

 6.1 Methodology ..................................................................................................................6-1 

 6.2 Protocol Development and Negotiation ......................................................................6-2 

 6.3 CALMET Model Configuration and Application......................................................6-2 

 6.4 CALPUFF Model Configuration and Application ....................................................6-2 

 6.4.1 Model Codes ........................................................................................................6-2

 6.4.2 Domain Definition...............................................................................................6-2 

 6.4.3 Model Set-Up.......................................................................................................6-3

 6.4.4 Emissions Input Development ...........................................................................6-4 

 6.4.5 CALPUFF Model Configuration.......................................................................6-5 

 6.4.6 Post Processing .....................................................................................................6-6

 6.5 Visibility Assessment ....................................................................................................6-7 

 6.5.1 Visibility Impacts from BART-Eligible Sources..............................................6-8 

 6.5.2 Change in Visibility Due to BART Controls ..................................................6-10 

 6.6 Presentation of Modeling Results ..............................................................................6-10 

 6.7 Reporting of CALPUFF Screening Assessment Modeling Results ........................6-10 

7.0 CALPUFF SOURCE-SPECIFIC APPLICATIONS.............................................................7-1 

 7.1 Methodology ..................................................................................................................7-1 

 7.2 Source-Specific Considerations ...................................................................................7-2 

 7.2.1 Protocol Development and Negotiation ............................................................7-2 

 7.2.2 Domain Definition...............................................................................................7-2 

 7.3 CALMET Configuration for Source-Specific Assessments ......................................7-2 
 

iii 

 7.4 CALPUFF Configuration for Source-Specific Assessments .....................................7-4 

 7.4.1 Background Conditions......................................................................................7-5 

 7.4.2 Ammonia Limiting Method (ALM) ..................................................................7-5 

 7.4.3 Computing Light Extinction ..............................................................................7-8 

 7.4.4 Estimating Rayleigh Scattering .........................................................................7-9 

 7.4.5 Natural Baseline Conditions ..............................................................................7-9 

 7.4.6 Visibility Impact Assessment ...........................................................................7-10 

 7.5 Assessment of Modeling Results ................................................................................7-10 

8.0 ALTERNATIVE MODEL APPLICATIONS.........................................................................8-1 

 8.1 Use of One-Atmosphere Models in Refined Assessments .........................................8-1 

 8.1.1 Regional Haze Modeling Data Bases.................................................................8-2 

 8.1.2 Obtaining Regional Haze Modeling Data Bases...............................................8-3 

 8.1.3 Protocol Development.........................................................................................8-3 

 8.2 Model Applications .......................................................................................................8-4 

 8.2.1 Regional Base Case Simulation..........................................................................8-4 

 8.2.2 BART Source Simulation with SGS Technology .............................................8-5 

 8.2.3 Assessing Modeled BART Source Impacts.......................................................8-5 

 8.3 Estimation of Natural Visibility Conditions...............................................................8-5 

 8.3.1 Flexibility Suggested by EPA.............................................................................8-5 

 8.3.2 Refined Procedures for One-Atmosphere Modeling .......................................8-6 

 8.4 Cumulative Impact Assessments .................................................................................8-7 

 8.5 Concluding Remarks ....................................................................................................8-7 

9.0 QUALITY ASSURANCE .........................................................................................................9-1 

 9.1 Objective of the QA Program ......................................................................................9-1 

 9.2 Quality Assurance Procedures.....................................................................................9-1 

 9.2.1 Input Data............................................................................................................9-2 

 9.2.2 MM5 and CALMET Applications.....................................................................9-2 

 9.2.3 CALPUFF Applications .....................................................................................9-3 

 9.2.4 Application of CALPOST and POSTUTIL......................................................9-4 

 9.2.5 QA Issues for Alternative Source-Specific Modeling ......................................9-5 

 9.3 Quality Assessment Summary .....................................................................................9-6 

REFERENCES ...................................................................................................................................R-1 

 
 

iv 

LIST OF FIGURES 

Figure 1-1. Federal Class I Areas in the United States .................................................................1-7 

Figure 1-2. U.S. Forest Service Class I Areas.................................................................................1-8 

Figure 1-3. National Park Service Class I Areas ...........................................................................1-9 

Figure 1-4. Fish and Wildlife Service Class I Areas....................................................................1-10 

Figure 1-5. Location of Visibility Monitoring Sites in the CENRAP Domain ..........................1-11 

Figure 1-6. CENRAP BART Modeling Flow Chart ....................................................................1-12 

Figure 3-1. CALPUFF Modeling System Components...............................................................3-18 

Figure 4-1. Plume Trajectory Paths and Growth Rates of Sub-Grid-Scale Reactive 

 Plumes within the CMAQ-PinG Model Simulation of the July 1995 SOS 

 Field Program in Nashville, TN.................................................................................4-17 

Figure 4-2. Reactive Plume Species Concentrations in the Cross Section from a High 

 NOx/Low SO2 Emissions Source at 5 Hours after Release .....................................4-18 

Figure 4-3. Aerosol Sulfate (SO4) Difference Field Determined by Subtracting the 

 CMAQ-NoPinG Concentrations from the CMAQ-PinG Concentrations 

 at 2 pm EDT on 7 July 1995.......................................................................................4-18 

Figure 4-4. Change in the Contributions of Fourteen (14) EGUs to Local 

Sulfate (SO4) Concentrations When the CMAQ-APT-PM Plume-in-Grid 

 Approach is Used .......................................................................................................4-19 

Figure 4-5. Change in the Contributions of Fourteen (14) EGUs to Local 

Nitrate (NO3) Concentrations When the CMAQ-APT-PM Plume-in-Grid 

 Approach is Used .......................................................................................................4-19 

Figure 4-6. CAMx PM PiG Simulation of Ozone Over the Upper Midwest on 

 14 June 2002: Plot on Right Reveals the Ozone Increments Associated 

 with Sub-Grid-Scale Treatment of Reactive Plumes...............................................4-20 

Figure 4-7. CAMx PM PiG Simulation of SO2 and Sulfate Over the Upper Midwest 

 on 14 June 2002: Plot on Right Reveals the SO2 and SO4 Increments 

 Associated with Sub-Grid-Scale Treatment of Reactive Plumes...........................4-20 

Figure 4-8. CAMx PM PiG Simulation of NO3 and NH4 Over the Upper Midwest 

 on 14 June 2002: Plot on Right Reveals the NO3 and NH4 Increments 

 Associated with Sub-Grid-Scale Treatment of Reactive Plumes............................4-21 
 

v 

Figure 4-9. Mean Fractional Bias and Error in Fine Particulate Species Predictions 

 from the CAMx, CMAQ, URM, and CMAQ-MADRID Models 

 over Several Regional PM and Visibility Model Evaluation Studies.....................4-22 

Figure 5-1. CENRAP North, Central, and South 6 km Meteorological Domains....................5-12 

Figure 5-2. CENRAP South Domain ............................................................................................5-13

Figure 5-3. CENRAP Central Domain .........................................................................................5-14 

Figure 5-4. CENRAP North Domain ............................................................................................5-15

Figure 5-5. Locations of IMPROVE, CASTNet, SEARCH, STN, and NADP 

 Monitoring Sites in and Near the CENRAP States .................................................5-16 

Figure 5-6. Locations of AQS Monitoring Sites in and Near the CENRAP States ..................5-17 

Figure 5-7. Spatial Mean Relative Humidity (%) over the Central Domain: 

 July 2002 States ...........................................................................................................5-18 

Figure 5-8. Spatial Mean Surface Temperature (deg C) over the Central Domain: 

 July 2002 5-21. .............................................................................................................5-18 

Figure 5-9. Wind Speed Index of Agreement over the Central Domain: July 2002.................5-19 

Figure 5-10. Standard Deviation in Wind Speed (m/s) over the Central Domain: 

 July 2002 5-21. .............................................................................................................5-19 

Figure 5-11. Root Mean Square Error in Wind Speed (m/s) over the Central Domain: 

 July 2002 5-21. .............................................................................................................5-20 

Figure 5-12. Scalar Mean Wind Speed (m/s) over the Central Domain: July 2002. .................5-20 

Figure 5-13. Vector Mean Wind Speed (m/s) over the Central Domain: July 2002...................5-21 

Figure 5-14. Normalized Bias in Relative Humidity (%) over the Central Domain: 

 July 2002 5-21. .............................................................................................................5-21 

Figure 5-15. Normalized Error in Relative Humidity (%) over the Central Domain: 

 July 2002 5-21. .............................................................................................................5-22 

Figure 5-16. Relative Humidity (%) at Kenosha, WI: July 2002 .................................................5-22 

Figure 5-17. Relative Humidity (%) at Topeka, KS: July 2002 ...................................................5-23 

Figure 5-18. Normalized Bias in Surface Temperature (%) over the Central 

 Domain: July 2002 ......................................................................................................5-23 
 

vi 

Figure 5-19. Normalized Error in Surface Temperature over the Central 

 Domain: July 2002 ......................................................................................................5-24 

Figure 5-20. Surface Temperature (deg C) at Kenosha, WI: July 2002......................................5-24 

Figure 5-21. Surface Temperature at Topeka, KS: July 2002......................................................5-25 

Figure 5-22. MM5/CALMET Relative Humidity Bias (%) by Month for Three 

 BART Modeling Years (2001, 2003, and 2003) .......................................................5-26 

Figure 5-23. MM5/CALMET Relative Humidity Error (%) by Month for Three 

 BART Modeling Years (2001, 2003, and 2003) .......................................................5-27 

Figure 5-24. MM5/CALMET Temperature Bias (deg C) by Month for Three 

 BART Modeling Years (2001, 2003, and 2003). ......................................................5-28 

Figure 5-25. MM5/CALMET Temperature Error (deg C) by Month for Three 

 BART Modeling Years (2001, 2003, and 2003) .......................................................5-29 

Figure 5-26. MM5/CALMET Wind Speed Index of Agreement by Month for 

 Three BART Modeling Years (2001, 2003, and 2003) ............................................5-30 

Figure 5-27. MM5/CALMET Relative Humidity Bias (%) over Three Years 

 in all CENRAP Domains ............................................................................................5-31 

Figure 5-28. MM5/CALMET Relative Humidity Error (%) over Three Years 

 in all CENRAP Domains ............................................................................................5-32 

Figure 5-29. MM5/CALMET Surface Temperature Bias (deg C) over Three Years 

 in all CENRAP Domains ............................................................................................5-33 

Figure 5-30. MM5/CALMET Surface Temperature Error (deg C) over Three 

 Years in all CENRAP Domains .................................................................................5-34 

Figure 5-31. MM5/CALMET Wind Speed Index of Agreement over Three 

 Years in all CENRAP Domains .................................................................................5-35 

Figure 6-1. Division of the U.S. for the Purpose of Assigning Default Natural 

 Background Concentrations (μg/m3) for Eastern and Western 

 U.S. Class I areas ...................................................................................................... 6-14 

Figure 7-1. POSTUTIL Processing of the Ammonia Limiting Method (ALM), 

 NO3/HNO3 Repartitioning for an Individual Source, and Estimating 

 Ammonia Consumption from Modeled Sources and Boundary Conditions ...... 7-15 

Figure 8-1. CENRAP 36/12 km CMAQ/CAMx Domain Used for 2002 Annual One- 

 Atmosphere Regional Haze Simulations .................................................................. 8-8 
 

vii 

Figure 8-2. MRPO 36 km CAMx Domain Used for 2001, 2002, and 2003 Annual One- 

 Atmosphere Regional Haze Simulations .................................................................. 8-9 

Figure 8-3. MRPO 36/12 km CAMx Domain Used for 2002 Annual One-Atmosphere 

 Regional Haze Simulations ...................................................................................... 8-10 

Figure 8-4. VISTAS 36/12 km CMAQ/CAMx Domain Used for 2002 Annual One- 

 Atmosphere Regional Haze Simulations ................................................................ 8-11 

Figure 8-5. WRAP 36 km CMAQ/CAMx Domain Used for 2002 Annual One- 

 Atmosphere Regional Haze Simulations ................................................................ 8-12 

Figure 8-6. Five States Study 36/12/4 km PM2.5/8-hr Ozone Study Using CAMx for 

 the 2002 Annual Period............................................................................................ 8-13 

Figure 8-7. Incremental 24-hr Average SO2, Sulfate, Nitrate, and NH4 

 Concentrations Fields on 14 June 2002 from the CAMx PM PiG 

 Simulation Over the Upper Midwest ...................................................................... 8-14 
 

viii 

LIST OF TABLES 

Table 1-1. Federally Mandated Class I Areas in the CENRAP States.....................................1-13 

Table 1-2. Federally Mandated Class I Areas Near the CENRAP States..................................1-3 

Table 3-1. Major Features of the CALMET Meteorological Model ........................................3-19 

Table 3-2. Major Features of the CALPUFF Dispersion Model ..............................................3-20 

Table 3-3. Parameter Variations in Box Model Simulations Used to Develop the 

 CALPUFF Sulfate and Nitrate Formation Algorithms...........................................3-22 

Table 5-1. CENRAP Lambert Conic Conformal Modeling Domain Specifications.................5-9 

Table 5-2. Vertical Layer Structure in CALMET Fields ............................................................5-9 

Table 5-3. Meteorological Model File Sizes for CENRAP BART Modeling .............................5-9 

Table 5-4. Statistical Evaluation of the CALMET Meteorological Fields for 2001-2003.......5-10 

Table 5-5. Overview of Ambient Data Monitoring Networks Covering the CENRAP 

 Domain ......................................................................................................................5-11 

Table 6-1. Contents of a Typical Screening BART Modeling Protocol ...................................6-12 

Table 6-2. CALMET/CALPUFF Model Codes for Screening Applications ...........................6-13 

Table 6-3. Default Natural Background Concentrations for Eastern and Western 

 U.S. Class I Areas........................................................................................................6-13 

Table 6-4. Federal Class I Areas in the CENRAP Domain.......................................................6-14 

Table 7-1. Contents of a Typical Source-Specific BART Modeling Protocol..........................7-11 

Table 7-2. Example of Hypothetical Impact Ranking at Six CENRAP Class I Areas ...........7-13