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APPENDIX B: EMISSIONS MODELING FOR THE DFW 

ATTAINMENT DEMONSTRATION SIP REVISION FOR THE 

1997 EIGHT-HOUR OZONE STANDARD

TABLE OF CONTENTS

Appendix B: Emissions Modeling for the DFW Attainment Demonstration SIP Revision for the 

1997 Eight-Hour Ozone Standard ...................................................................................................1

List of Tables................................................................................................................................... 3

List of Figures ................................................................................................................................. 6

1. General Modeling Emissions Development............................................................................ 8

1.1 Base Case Modeling Emissions...................................................................................... 8

1.2 Baseline Modeling Emissions ........................................................................................ 9

1.3 Future Year Modeling Emissions..................................................................................10

2 Point Source Modeling Emissions Development ................................................................... 11

2.1 2006 Base Case Point Source Modeling Emissions Development............................... 11

2.1.1 Texas Point Sources ......................................................................................... 11

2.1.2 Regional (Outside of Texas) Point Sources......................................................17

2.1.3 Plume-in-Grid (PiG) Source Selection............................................................ 27

2.1.4 Summary of June 2006 Base Case Point Sources .......................................... 27

2.2 2006 Baseline Point Source Modeling Emissions Development................................. 28

2.2.1 Texas Point Sources ........................................................................................28

2.2.2 Outside Texas.................................................................................................. 36

2.2.3 Summary of 2006 Baseline Point Sources ..................................................... 38

2.3 2012 Future Year Point Source Modeling Emissions Development............................ 39

2.3.1 Attainment Areas of Texas.............................................................................. 39

2.3.2 Nonattainment Areas (NAAs) of Texas .......................................................... 47

2.3.3 Regional (Outside of Texas) Point Sources..................................................... 53

2.3.4 Offshore, Mexico, and Canada........................................................................ 58

2.3.5 Summary of Future Case Point Source Data Files.......................................... 58

3 On-Road Mobile Source Modeling Emissions Development................................................ 60

3.1 On-Road Mobile Source Emissions Inventories for Nine-County DFW.....................60

3.2 On-Road Mobile Source Emissions Processing........................................................... 63

3.2.1 Texas Low Emission Diesel Fuel Benefits ...................................................... 65
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3.3 Nine-County DFW Photochemical Modeling Input .................................................... 66

3.4 Attainment Demonstration Motor Vehicle Emissions Budget.................................... 68

3.5 On-Road Mobile Source Emissions Inventories for Non-DFW Areas ........................ 73

4 Non-Road, Off-road, And Area Source Modeling Emissions.................................................75

4.1 Texas Oil and Gas Production Emission Inventory Development ...............................75

4.2 Texas Drilling Rigs Emission Inventory Development.................................................81

4.3 Louisiana Haynesville Shale Oil and Gas..................................................................... 87

4.4 Airports ........................................................................................................................90

4.5 Locomotives ................................................................................................................. 93

4.6 Non-road/TexN............................................................................................................98

4.7 Area Sources............................................................................................................... 104

4.8 Ship Emissions............................................................................................................110

5 Biogenic Modeling Emissions .............................................................................................. 112

5.1 Future Improvements ................................................................................................. 117

6 References............................................................................................................................. 119

Attachment 1: Texas 2010 CAIR NOX Allocations.......................................................................120

Attachment2: On-Road Mobile Source Modeling Emissions Development with MOBILE6.2 .. 131

On-Road Mobile Source Emissions Inventories for Nine-County DFW Area ............................ 131

On-Road Mobile Source Emission Adjustments and Controls ............................................135

Temperature/Humidity NOX Correction....................................................................136

Reformulated Gasoline Benefits ................................................................................ 138

Low Reid Vapor Pressure Gasoline Benefits.............................................................. 138

Inspection/Maintenance Program Benefits ...............................................................139

Texas Low Emission Diesel Fuel Benefits.................................................................. 140

On-Road Control Strategy Benefits Summary............................................................ 141

Nine-County DFW Photochemical Modeling Input.............................................................142

Attainment Demonstration Motor Vehicle Emissions Budget.............................................144

On-Road Mobile Source Emissions Inventories for Non-DFW Areas .................................150

Attachment 3: Alternative Point Source Growth Modeling Sensitivity....................................... 152
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LIST OF TABLES

Table 1: Summary of Base Case Point Source Emission Data Sources........................................... 9

Table 2: Summary of Base Case On-road Mobile Source Emission Data Sources......................... 9

Table 3: Summary of Base Case Non-road Mobile, Area, Oil and Gas, and Biogenic Source 

Emission Data Sources...................................................................................................... 9

Table 4: Sources of Point Source Emissions Data ......................................................................... 11

Table 5: Summary of PiG Thresholds Chosen .............................................................................. 27

Table 6: Base Case AFS File for the DFW June 2006 Episode..................................................... 27

Table 7: 2006 DFW Base Case Episode Day (June 14, 2006) Emissions Summary.................... 28

Table 8: 2006 Baseline OSD Emissions in Texas ......................................................................... 28

Table 9: 2006 Baseline Hourly Texas Acid Rain EGU Emissions................................................ 29

Table 10: 2006 Baseline Emissions Summary for Non-ARD Points Outside of Texas................ 37

Table 11: 2006 Baseline Hourly Emissions Summary for ARD Points Outside of Texas............. 37

Table 12: AFS Files for the 2006 Baseline .................................................................................... 38

Table 13: 2006 Baseline Point Source Emissions Summary ........................................................ 39

Table 14: Newly Permitted EGUs (post 2008) in Texas as of December 2010 .............................41

Table 15: Summary of Texas Attainment Area Growth Projections to 2012................................ 44

Table 16: Distribution of NOX CAIR Allowances in Texas............................................................ 46

Table 17: Banked Emissions as of July 2010 ................................................................................ 49

Table 18: Texas NEGU “No-Rules” Growth Summary ................................................................. 50

Table 19: Ellis County Cement Kiln NOX Caps ............................................................................. 52

Table 20: Detailed NOX 2012 Emissions Summary by Region..................................................... 53

Table 21: Modeled CAIR Phase I NOX Allocations for States in the Modeling Domain............... 54

Table 22: Modeled 2012 Typical Day Acid Rain EGU Emissions for Regional States ................. 55

Table 23: 2012 Regional States NEGU Emissions........................................................................ 56

Table 24: 2012 Regional States Emissions Summary ...................................................................57

Table 25: AFS Files for the 2012 Future Case Episode................................................................. 58

Table 26: 2012 Future Case Point Source Emissions Summary .................................................. 59

Table 27: VMT, NOX, VOC, and CO Summary for 2006 DFW On-Road Inventory.....................60

Table 28: VMT, NOX, VOC, and CO Summary for 2012 DFW On-Road Inventory.....................60

Table 29: Summary of 2006 DFW Summer Weekday On-Road Inventory by County ................61

Table 30: Summary of 2012 DFW Summer Weekday On-Road Inventory by County .................61

Table 31: Summary of 2006 DFW Summer Weekday On-Road Inventory by Vehicle Type....... 62

Table 32: Summary of 2012 DFW Summer Weekday On-Road Inventory by Vehicle Type ....... 62

Table 33: EPS3 Modules Used to Process Nine-County DFW On-Road Emissions Data............ 63

Table 34: 2006 Diesel Fuel Combination Long-Haul Truck Extended Idling Emissions for NineCounty DFW.................................................................................................................... 64
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Table 35: 2012 Diesel Fuel Combination Long-Haul Truck Extended Idling Emissions for NineCounty DFW.................................................................................................................... 64

Table 36: Summary of 2006 Summer Weekday TxLED Benefits by Vehicle Type...................... 65

Table 37: Summary of 2012 Summer Weekday TxLED Benefits by Vehicle Type....................... 66

Table 38: 2006 Summer Weekday On-Road Mobile Source Inventory by County ..................... 66

Table 39: 2012 Summer Weekday On-Road Mobile Source Inventory by County ...................... 67

Table 40: 2006 On-Road Mobile Source Inventory by Day Type ................................................ 67

Table 41: 2012 On-Road Mobile Source Inventory by Day Type.................................................. 67

Table 42: 2012 Attainment Demonstration MVEB for the Nine-County DFW Area................... 68

Table 43: On-Road Inventory Development by Area Within the Modeling Domain................... 73

Table 44: 2006 Oil and Gas Production EI breakout....................................................................75

Table 45: 2012 Oil and Gas Production EI breakout.................................................................... 76

Table 46: 2006 Baker-Hughes Rig Counts for TRRC Districts .....................................................81

Table 47: 2008 Baker-Hughes Rig Counts for TRRC Districts .....................................................81

Table 48: RigData.com data for Barnett Shale Rig Counts .......................................................... 82

Table 49: 2006 DFW 9-county Drilling Rig EI............................................................................. 83

Table 50: Baker-Hughes 2008 to 2010 Rig Count Ratios by TRRC District................................ 83

Table 51: Baker-Hughes Rig Counts for Barnett Shale Counties for 2008 and late 2010 ........... 84

Table 52: 2012 DFW 9-county Drilling Rig EI .............................................................................84

Table 53: 2006 DFW 9-county Airport EI....................................................................................90

Table 54: 2012 DFW 9-county Airport EI ....................................................................................90

Table 55: 2006 DFW 9-county Locomotive EI............................................................................. 93

Table 56: 2012 DFW 9-county Locomotive EI ............................................................................. 93

Table 57: 2006 NONROAD DFW 9-county EI breakout..............................................................98

Table 58: 2012 NONROAD DFW 9-county EI breakout.............................................................101

Table 59: 2006 Area Source DFW 9-county EI breakout........................................................... 104

Table 60: 2012 Area Source DFW 9-county EI breakout............................................................107

Table 61: Example GloBEIS3.1 Hourly Biogenic Emissions Report for June 2, 2006................ 115

Table 62: Daily Summary of Biogenic Emissions for the 2006 DFW Ozone Episode. ............... 116

Table 63, Att. 1: Texas 2010 CAIR NOX Allocations ................................................................... 120

Table 64, Att. 2: VMT, NOX, VOC, and CO Summary for 2006 DFW On-Road Inventory......... 131

Table 65, Att. 2: VMT, NOX, VOC, and CO Summary for 2012 DFW On-Road Inventory .........132

Table 66, Att. 2: Summary of 2006 DFW Summer Weekday On-Road Inventory by County....132

Table 67, Att. 2: Summary of 2012 DFW Summer Weekday On-Road Inventory by County.....132

Table 68, Att. 2: Summary of 2006 DFW Summer Weekday On-Road Inventory by Vehicle Type

........................................................................................................................................133

Table 69, Att. 2: Summary of 2012 DFW Summer Weekday On-Road Inventory by Vehicle Type

........................................................................................................................................134
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Table 70, Att. 2: EPS3 Modules Used to Process Nine-County DFW On-Road Emissions Data135

Table 71, Att. 2: 2006 HDDV8a and HDDV8b Extended Idling Emissions for Nine-County DFW

........................................................................................................................................136

Table 72, Att. 2: 2012 HDDV8a and HDDV8b Extended Idling Emissions for Nine-County DFW

........................................................................................................................................136

Table 73, Att. 2: Summary of 2006 Temperature/Humidity On-Road NOX Correction ............ 137

Table 74, Att. 2: Summary of 2012 Temperature/Humidity On-Road NOX Correction.............137

Table 75, Att.2: Summary of 2006 Summer Weekday RFG Benefits by County ........................138

Table 76, Att. 2: Summary of 2012 Summer Weekday RFG Benefits by County ........................138

Table 77, Att. 2: Summary of 2006 Summer Weekday Low RVP Gasoline Benefits by County.139

Table 78, Att. 2: Summary of 2012 Summer Weekday Low RVP Gasoline Benefits by County .139

Table 79, Att. 2: Summary of 2006 Summer Weekday I/M Program Benefits by County .........139

Table 80, Att. 2: Summary of 2012 Summer Weekday I/M Program Benefits by County ........ 140

Table 81, Att. 2: Summary of 2006 Summer Weekday TxLED Benefits by Vehicle Type ......... 140

Table 82, Att. 2: Summary of 2012 Summer Weekday TxLED Benefits by Vehicle Type........... 141

Table 83, Att. 2: Summary of 2006 Summer Weekday On-Road Control Strategy Benefits......142

Table 84, Att. 2: Summary of 2012 Summer Weekday On-Road Control Strategy Benefits ......142

Table 85, Att. 2: 2006 Summer Weekday On-Road Mobile Source Inventory by County..........142

Table 86, Att. 2: 2012 Summer Weekday On-Road Mobile Source Inventory by County ..........143

Table 87, Att. 2: 2006 On-Road Mobile Source Inventory by Day Type.....................................143

Table 88, Att. 2: 2012 On-Road Mobile Source Inventory by Day Type .....................................143

Table 89, Att. 2: 2012 Attainment Demonstration MVEB for the Nine-County DFW Area .......144

Table 90, Att. 2: On-Road Inventory Development by Area within the Modeling Domain........ 151

Table 91, Att. 3: 2012 Future Design Values Using the DERC Flow Control Limit or TIPI-REMIEGAS Growth .................................................................................................................153
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LIST OF FIGURES

Figure 1: Tileplot of DFW ARD NOX Emissions for 06 June 2006 ...............................................16

Figure 2: Tileplot of Louisiana ARD NOX Emissions for 14 June 2006........................................19

Figure 3: Tileplot of Arkansas ARD NOX Emissions for 14 June 2006........................................ 20

Figure 4: Tileplot of Oklahoma ARD NOX Emissions for 14 June 2006.......................................21

Figure 5: Tileplot of Remaining States ARD NOX Emissions for 14 June 2006 .......................... 22

Figure 6: Tileplot of Offshore NOX for a representative June day ............................................... 23

Figure 7: Tileplot of Offshore VOC for a representative June day ............................................... 24

Figure 8: Tileplot of representative Mexican OSD NOX ............................................................... 25

Figure 9: Tileplot of representative Mexican OSD VOC............................................................... 26

Figure 10: DFW Elevated NOX.......................................................................................................31

Figure 11: DFW Elevated VOC...................................................................................................... 32

Figure 12: DFW Low-level NOX .................................................................................................... 33

Figure 13: DFW Low-level VOC.................................................................................................... 34

Figure 14: HGB HRVOC Reconciliation ....................................................................................... 35

Figure 15: HGB Tank Landing Losses VOC.................................................................................. 36

Figure 16: 2006 DFW Summer Weekday NOX Emissions ........................................................... 69

Figure 17: 2006 DFW Summer Weekday VOC Emissions ........................................................... 70

Figure 18: 2012 DFW Summer Weekday NOX Emissions.............................................................71

Figure 19: 2012 DFW Summer Weekday VOC Emissions............................................................ 72

Figure 20: 2006 Oil and Gas Production NOX for the DFW 4 km Domain ..................................77

Figure 21: 2006 Oil and Gas Production cb05 VOC for the DFW 4 km Domain......................... 78

Figure 22: 2012 Oil and Gas Production NOX for the DFW 4 km Domain ................................. 79

Figure 23: 2012 Oil and Gas Production cb05 VOC for the DFW 4 km Domain .........................80

Figure 24: TRRC Districts.............................................................................................................82

Figure 25: 2006 Drilling Rig NOX for the DFW 4 km Domain....................................................86

Figure 26: 2012 Drilling Rig NOX for the DFW 4 km Domain .....................................................86

Figure 27: 2006 (left) and 2012 (right) Drilling Rig NOX for the DFW 4 km Domain................. 87

Figure 28: 2012 Louisiana Haynesville Shale Drill Rig NOX EI...................................................88

Figure 29: 2012 Additional Haynesville Oil and Gas Production cb05 VOC ...............................89

Figure 30: 2006 DFW9-county airport-specific NOX EI...............................................................91

Figure 31: 2012 DFW 9-county airport-specific NOX EI .............................................................. 92

Figure 32: 2006 DFW 9-county Line-haul Locomotive NOX EI .................................................. 94

Figure 33: 2006 DFW 9-county Switcher Locomotive NOX EI.................................................... 95

Figure 34: 2012 DFW 9-county Line-haul Locomotive NOX EI................................................... 96

Figure 35: 2012 DFW 9-county Switcher Locomotive NOX EI..................................................... 97

Figure 36: 2006 DFW 9-county Non-road NOX EI...................................................................... 99

Figure 37: 2006 DFW 9-county Non-road VOC EI.................................................................... 100
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Figure 38: 2012 DFW 9-county Non-road NOX EI..................................................................... 102

Figure 39: 2012 DFW 9-county Non-road VOC EI......................................................................103

Figure 40: 2006 DFW 9-county Area Source NOx EI.................................................................105

Figure 41: 2006 DFW 9-county Area Source cb05 VOC EI........................................................ 106

Figure 42: 2012 DFW 9-county Area Source NOX EI................................................................ 108

Figure 43: 2012 DFW 9-county Area Source cb05 VOC EI........................................................ 109

Figure 44: 2006 STEEM Ship Emissions for Gulf of Mexico for 12 km Domain.........................111

Figure 45: TCEQ Land Cover for the 4 km DFW CAMx Domain................................................ 113

Figure 46: New TCEQ land cover produced by Texas A&M University for the 12 km 

meteorological modeling domain................................................................................... 117

Figure 47, Att. 2: 2006 DFW Summer Weekday NOX Emissions ...............................................146

Figure 48, Att. 2: 2006 DFW Summer Weekday VOC Emissions...............................................147

Figure 49, Att. 2: 2012 DFW Summer Weekday NOX Emissions................................................148

Figure 50, Att. 2: 2012 DFW Summer Weekday VOC Emissions ...............................................149

Figure 51, Att. 3: June 14 Eight-Hour Ozone Max Difference Tile Plot Comparing DERC Flow 

Control Limit to TIPI-REMI-EGAS Growth ..................................................................152
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1. GENERAL MODELING EMISSIONS DEVELOPMENT

The EPA’s Guidance on the Use of Models and Other Analyses for Demonstrating Attainment of 

Air Quality Goals for Ozone, PM2.5, and Regional Haze (EPA, 2007) specifies a procedure for 

demonstrating attainment through modeling. Instead of using the model results in an absolute 

sense, the eight-hour ozone procedure uses the modeling results in a relative sense. This 

relative approach is based on how the model responds to the reduction in emissions between a 

baseline and a future year. Therefore, the photochemical modeling process for attainment 

demonstration requires four modeling emissions data sets: 

• base case emissions

• baseline emissions

• future year emissions

• future year control strategy emissions

1.1 Base Case Modeling Emissions 

In order for the photochemical model to be used in the attainment demonstration, the model 

needs to be capable of adequately replicating historical episodes (base cases) for which high 

daily eight-hour ozone was measured. To maximize model performance, base case emission 

inputs are estimated as accurately as possible. In the development of the base case modeling 

emissions, a number of quality assurance techniques are used to evaluate the reasonableness of 

the emission magnitudes, along with their spatial distribution and temporal profile. Using the 

quality assured episode-specific emissions along with other modeling inputs (e.g., meteorology), 

the photochemical model is run and the simulated concentrations of both ozone and ozone 

precursors (e.g., NOX, VOC) are compared to the measured concentrations to evaluate the 

adequacy of the photochemical model in replicating the base case. If the evaluation indicates 

that the base case is not adequately replicated, then diagnostics are conducted to determine 

which modeling inputs are insufficient. When the emissions are implicated, the modeling 

emissions are reviewed and pertinent revisions are made as appropriate. If the evaluation 

implicated other inputs or once the photochemical model adequately replicates the base case, 

then the modeling emissions are considered to be sufficiently representative of the episode. 

A summary of the primary data sources for the development of the base case modeling 

emissions is provided in Table 1: Summary of Base Case Point Source Emission Data Sources, 

Table 2: Summary of Base Case On-road Mobile Source Emission Data Sources, and Table 3: 

Summary of Base Case Non-road Mobile, Area, Oil and Gas, and Biogenic Source Emission Data 

Sources. 
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Table 1: Summary of Base Case Point Source Emission Data Sources

Region Data Source

Texas 2006 State of Texas Air Reporting System (STARS)

LA, AR, OK 2004, 2005 individual NEIs

Other (Regional) 2002 CenRAP/RPOs EI

All States 2006 EPA hourly Acid Rain data

Texas 2006 hourly Special Inventory surveys

Harris County 2006 hourly Harris County Tank Landing Loss surveys

HGB 2006 HGB HRVOC reconciliation

Offshore 2005 MMS GWEI platforms of western Gulf of Mexico

Mexico 1999 Phase III Mexico National Emissions Inventory (NEI)

Canada 1995 from EPA’s Clean Air Interstate Rule (CAIR) 2001 base modeling

Table 2: Summary of Base Case On-road Mobile Source Emission Data Sources

Region Data Source

DFW 2006 based on MOVES2010a and local travel demand model (TDM) for 

vehicle miles traveled (VMT)

Other Texas 2006 based on MOVES2010a and Highway Performance Monitoring 

System (HPMS) for VMT

Outside Texas 2006 based on MOVES2010a and EPA’s National Mobile Inventory Model 

(NMIM)

Table 3: Summary of Base Case Non-road Mobile, Area, Oil and Gas, and Biogenic

Source Emission Data Sources

Region

Non-road Mobile 

Sources Area Sources

Oil and Gas 

Sources Biogenics

Texas

2005 TexAER, 

Texas NONROAD 

(TexN) model

2005 TexAER

2008 TexAER, 

2006 Texas 

Railroad 

Commission, 

Baker Hughes, 

RigData.com

GloBEIS3.1 with TAMU 

LULC data

Outside 

Texas 2006 NMIM 2002 EPA NEI 2002 EPA NEI GloBEIS3.1 with BELD3 LULC data

Emissions were developed for the ozone precursors of NOX, VOC, and CO. The emission 

inventories (EIs) are prepared for photochemical modeling input using Version 3 of the 

Emissions Processing System (EPS3). 

1.2 Baseline Modeling Emissions 

The EPA procedure for demonstrating attainment requires the development of modeling 

emissions for a baseline year to be used with similarly developed future year emissions. In order 

to keep the baseline and future year modeling emissions commensurate, more generic non-
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episodic ozone season day (OSD) emissions are developed for the baseline year. The OSD 

modeling emissions for the baseline and future years are developed using the same averaging 

and estimating procedures, which provides an appropriate basis for assessing the photochemical 

model response to emission reductions. 

The major difference between the base case and baseline modeling emissions is the treatment of 

the hourly-specific emissions for elevated point sources, such as electric generating units 

(EGUs). Emissions for the other source categories are identical between the base cases and 

baseline modeling emissions. 2006 was chosen as the baseline year and Section 2.2describes 

the averaging processes used in the development of the baseline inventory. 

1.3 Future Year Modeling Emissions 

With a classification of severe, the eight-hour ozone attainment date for DFW is June 15, 2013.

The modeling attainment year is 2012 because it is the full ozone season prior to the attainment

date. Modeling emissions for the 2012 future year were estimated by applying growth 

projections and control measures to the 2006 baseline modeling emissions. The 2012 modeling 

emissions include the benefits of the Federal Motor Vehicle Control Program (FMVCP), Mass 

Emissions Cap and Trade (MECT) Program, the Highly Reactive VOC Emission Cap and Trade 

(HECT) Program in the Houston-Galveston-Brazoria (HGB) area, and Phase One of the Clean 

Air Interstate Rule (CAIR).
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2 POINT SOURCE MODELING EMISSIONS DEVELOPMENT

Much of the point source emissions development began with the March 2010 HGB SIP Revision 

as a starting point, because the first half of the 2006 base case was developed for the recent HGB 

SIP modeling. Some of the descriptions of this DFW work will refer to the March 2010 

Appendix B: Emissions Modeling for the HGB Attainment Demonstration SIP Revision for the 

1997 Eight-Hour Ozone Standard, hereafter referred to as the “March 2010 HGB Appendix B,” 

especially for descriptions of HGB-specific emissions development. 

The various data sources that went into the development of the point source modeling emissions 

are summarized in Table 4: Sources of Point Source Emissions Data. The TCEQ compiled and 

formatted the data to generate modeling datasets for the base case, the baseline, and the future 

case studies as detailed in the following sections.

Table 4: Sources of Point Source Emissions Data

Sources of Data Calendar Year(s) 

Used

TCEQ State of Texas Air Reporting System (STARS) 2006

TCEQ Hourly Floating Roof Tank Landing Loss (TLL) Surveys 2006

TCEQ-derived Highly Reactive VOC (HRVOC) Reconciliation using 

Potential Source Contribution Factor (PSCF) Methodology

2006

EPA Clean Air Markets Division (CAMD) Acid Rain Program Continuous 

Emission Monitors (CEMs) for all states

2006, 2008

EPA/TCEQ Clean Air Interstate Rule (CAIR) 

allocations for entire modeling domain

2010

Electric Reliability Council of Texas 2010

Louisiana Department of Environmental Quality(LDEQ) 2004

Oklahoma Department of Environmental Quality(ODEQ) 2005

Arkansas Department of Environmental Quality(ADEQ) 2005

U.S. Department of the Interior Minerals Management Service (MMS) 

Gulf-Wide Emissions Inventory (GWEI) 

of Offshore Platforms

2005

Central States Regional Air / Regional Planning Organizations 

(CenRAP/RPO) regional emissions inventory 

2002, 2018

Canada from the EPA’s CAIR 2001 base case 1995

Mexico from Mexican NEI Phase III 1999

2.1 2006 Base Case Point Source Modeling Emissions Development

The following subsections describe development of the base case point source modeling 

emissions for all portions of the domain used for this June 2006 DFW modeling episode. 

2.1.1

For Texas point sources, OSD emissions data from State of Texas Air Reporting System (STARS)

and hourly emissions data from the EPA’s acid rain database (ARD) provided the basis for 

modeling the 2006 base case episode. Additionally, a supplemental “extra olefins” file was 

developed to account for reconciled HRVOC emissions in the HGB area. HRVOC include 

ethylene, propylene, 1,3-butadiene, and all isomers of butene. Episode-specific survey results of 

HGB floating roof tank landing losses (TLL) were averaged and used to develop files of hourly 

Texas Point Sources
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emissions for the 2006 episode. The following subsections describe the development of 

modeling emissions for each of these components.

2.1.1.1 State of Texas Air Reporting System (STARS)

Point source emissions and industrial process operating data are collected annually from sites 

that meet the reporting requirements of 30 Texas Administrative Code (TAC) §101.10. To collect 

data, the TCEQ mails annual emissions inventory questionnaires (EIQs) to all sources identified 

as meeting the reporting requirements. Subject entities are required to report levels of 

emissions subject to regulation from all emissions-generating units and emissions points, and 

also must provide representative samples of calculations used to estimate the emissions. 

Descriptive information is also required on process equipment, including operating schedules, 

emission control devices, abatement device control efficiencies, and emission point discharge 

parameters such as location, height, diameter, temperature, and exhaust gas flow rate. All data 

submitted in the EIQ are subjected to quality assurance (QA) procedures. The data are then 

stored in the STARS database. The TCEQ reports point source emissions data to the EPA for 

inclusion in the National Emissions Inventory (NEI).

Annually, the TCEQ collects emissions information from approximately 2000 major point 

sources. In nonattainment areas, major point sources are defined for inventory reporting 

purposes as industrial, commercial, or institutional sources that emit actual levels of criteria 

pollutants at or above the following amounts: 10 tons per year (tpy) of VOC; 25 tpy of NOX; or 

100 tpy of any of the other criteria pollutants including CO, SO2, PM10, or lead. For the 

attainment areas of the state, any company that emits a minimum of 100 tpy of any criteria 

pollutant must submit an inventory. Additionally, any source that either generates or has the 

potential to generate at least 10 tpy of any single Hazardous Air Pollutant (HAP) or 25 tpy of 

aggregate HAPs is required to report emissions to the TCEQ. The reporting requirements, 

guidance documents, trends, and summaries of the most recently quality assured year of 

reported data can be found at 

http://www.tceq.state.tx.us/implementation/air/industei/psei/psei.html.

Development of the Texas point source emission modeling files began with queries of the 

quality-assured data of the STARS database. Updated modeling query reports are typically run 

when significant STARS updates are completed. The STARS modeling extract report (“STARS 

extract”) is a snapshot of Texas emissions since emissions from previous years can be updated 

by the regulated entities.

SAS computer programming code was written, updated, and/or modified to parse the STARS 

extract, perform various logical checks and comparisons, assign defaults for missing data, apply

rule effectiveness to VOC paths with control devices, and format the data into an AIRS Facility 

Subsystem (AFS) file that can be processed with the modules of Version 3 of the Emissions 

Processor System (EPS3).

The STARS extract contains all four types of emission rates, annual, OSD, emission events (EE), 

and scheduled maintenance startup and shutdown (SMSS). Typical modeled ozone season day 

emissions include the OSD emission rate, which is representative of average daily emissions 

during the summer, as well as prorated EE and SMSS emissions. The TCEQ defines the ozone 

season for EI reporting purposes as June through August. This is generally the time of the year 

that monitored ozone concentrations are highest. The annual emission rate is used when OSD 

rates are not reported. An example of STARS extract data is available in the March 2010 HGB 

Appendix B, Section 2.1.1.
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2.1.1.2 Rule Effectiveness (RE)

RE is applied to the STARS VOC emissions where appropriate to account for the reality that not 

all facilities covered by a rule are in compliance with the rule 100 percent of the time. RE also 

accounts for the fact that control equipment does not always operate at its assumed control 

efficiency. Additional details about rule effectiveness and how it is applied by the TCEQ are in 

the March 2010 HGB Appendix B, Section 2.1.1. 

2.1.1.3 Preparation of AFS File for EPS3 Input

The resultant AFS file is in a format ready for input to EPS3. The STARS-derived AFS file for all 

criteria pollutants typically has more than 200,000 records. Each point source emissions path 

contains references for the TCEQ account (RN), equipment (FIN), and exhaust point (EPN). 

For ozone modeling purposes, values for the ozone precursors of NOX, VOC, and CO are retained 

in the AFS file for EPS3 input. An example AFS record with explanations, specific QA steps, and 

file naming conventions can be found in the March 2010 HGB Appendix B, Section 2.1.1. The 

AFS file format used by the TCEQ for this modeling, including field descriptions and options,

can be found on the TCEQ FTP modeling site,

ftp://amdaftp.tceq.texas.gov/pub/HGB8H2/ei/point/AFS-EPS3-v3.doc

2.1.1.4 Preparation of Photochemical Model-Ready Files with EPS3

.

EPS3 is used to process the emissions in the AFS file into a format ready for photochemical 

model input. Photochemical model inputs require that the emissions be, in EPS3 order 

performed by the TCEQ:

• chemically speciated into groups of compounds with similar reactivity for the formation of 

ozone;

• temporally allocated by hour of day, day of week, etc.; and

• spatially allocated to grid cells or assigned to fixed points.

The EPS3 User’s Guide provides additional details for processing the point source emissions for 

photochemical model input and can be found at 

ftp://amdaftp.tceq.texas.gov/pub/HGB8H2/ei/EPS3_manual/EPS3UG_UserGuide_200908.p

df. The remainder of this section discusses some of the specific point source emissions 

processing procedures. Excerpts of the data, which provide a better understanding of the 

processes, can be found in the March 2010 HGB Appendix B, Section 2.1.1.

2.1.1.4.1 Chemical Speciation with EPS3

VOC emissions in STARS can be reported as individual compounds, mixtures, classes of 

compounds, total VOC, and unclassified VOC. The VOC values that are included in the AFS file 

are speciated into carbon bond groups of similar ozone reactivity that will be recognized by the 

specific chemical mechanism of the photochemical model. For operational efficiency, most 

photochemical modeling studies are not based on separate algorithms for each individual 

reaction. Instead, groups of compounds with similar reactivity for the formation of ozone are 

grouped together and input into the photochemical model. The TCEQ used the Carbon Bond 

2005 (CB05) chemical mechanism.

The majority of TCEQ EIQ responses include constituent VOC emission rates, which are used to 

develop point-specific speciation profiles. When the composition of the VOC reported for a 

specific source is unknown or not fully-speciated, the default speciation profile is applied based 

on the source classification code (SCC). More detail on the TCEQ source-specific speciation 

approach is available in the March 2010 HGB Appendix B, Section 2.1.1.5 and in a paper and 

presentation given at the 17th Annual International Emission Inventory Conference (Portland, 
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Oregon, 2008). The paper is titled Emissions Modeling of Specific Highly Reactive Volatile 

Organic Compounds (HRVOC) in the Houston-Galveston-Brazoria Ozone Nonattainment 

Area, and is available at http://www.epa.gov/ttn/chief/conference/ei17/session6/thomas.pdf

2.1.1.4.2 Temporal Allocation with EPS3

.

Even though OSD is typically used for processing of photochemical modeling emissions, EPS3 

can temporally distribute emissions by month, week, day, and hour of a specific episode when 

sufficient detail is provided in the EIQ. March 2010 HGB Appendix B, Section 2.1.1.5 provides 

detail about temporal allocation, along with examples of the cross reference and profile records.

2.1.1.4.3 Spatial Allocation with EPS3

Photochemical models generally rely on a three-dimensional Eulerian system where emissions 

are allocated to individual grid cells. Emissions occur at the surface for most source categories 

such as area, biogenic, on-road, and non-road, and are classified as low-level. Numerous point 

sources also fall into the low-level surface category, but large combustion sources such as power 

plants are categorized as elevated because their hot exhaust gases can rise several hundred 

meters into the atmosphere.

Low-level point sources are allocated to grid cells and merged with the other source categories 

prior to photochemical model input. Elevated point sources are kept at their reported X-Y 

locations and assumed to emit from the calculated effective plume height of Z to better simulate 

physical mixing in the elevated layers of the photochemical model. As with other advanced 

emissions processors, EPS3 processing of point source emissions is divided into low-level and 

elevated streams, which provides better simulation of how elevated emissions are distributed 

prior to mixing and reacting with surface emissions. The drawbacks are more complicated EPS3 

processing and longer photochemical model run times. 

The photochemical model inputs for point sources consist of a single low-level gridded merged 

file and a single file of elevated sources. A plume cutoff height of 30 meters was chosen to divide 

the point sources into low-level and elevated categories. The emissions from elevated sources 

can be individually tracked, and NOX reaction chemistry can be enhanced by treating these 

plumes as Lagrangian puffs by use of the optional Plume-in-Grid (PiG) treatment. The TCEQ 

uses the Greatly Reduced Execution and Simplified Dynamics (GREASD) PiG option in CAMx, 

which is most applicable to large NOX plumes. More detail on the GREASD PiG approach is 

provided below in Section 2.1.3.

2.1.1.5 Hourly Acid Rain Program Database (ARPDB)

NOX emission estimates for EGUs, or large power plants, were obtained from EPA’s Clean Air 

Markets Division (CAMD) ARPDB. EPA’s Acid Rain Program applies to both new and existing 

EGUs with an output capacity of greater than 25 megawatts and more than one-third of their 

output sent to the electrical grid. Under the Acid Rain Program, each unit must continuously 

measure and record its emissions of sulfur dioxide (SO2), NOX, and carbon dioxide (CO2). In 

most cases, a continuous emission monitoring (CEM) system must be used. EGUs report hourly 

emissions data to the EPA on a quarterly basis. These data are stored in the Emissions Tracking 

System which serves as a repository of data for the utility industry. The EPA quality assures the 

raw hourly data and provides both datasets and a query wizard on the CAMD website for 

downloading the data. Missing or invalid hourly data that arise from CEM equipment problems 

are provided by the EPA using specific substitution criteria. Thus, EGU-reported data does not 

always match that from EPA’s CAMD. The data can be downloaded by ORISPL (site) and Unit

ID (point) for any state for any quarter. The user has several dataset options, as well as output 
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options within some datasets. The website for these data is 

http://camddataandmaps.epa.gov/gdm/index.cfm?fuseaction=emissions.wizard.

Hourly data were downloaded from CAMD for Texas and all other states within the modeling 

domain for the 2006 episode for both the second and third calendar quarters, since the model 

uses a few days immediately before and after the episode. These are hereafter referred to as 

ARD (Acid Rain data) sources.

ARD emissions greatly improve the temporal resolution of the point source inventory because 

the ARD distinguishes between EGUs that operate throughout the day as baseload units and 

EGUs that operate more intermittently as peaking units. March 2010 HGB Appendix B, Section 

2.1.6 describes in more detail, with examples, how the ARD are converted to hourly AFS

emissions records.

Figure 1: Tileplot of DFW ARD NOX Emissions for 06 June 2006 is a tileplot of ARD NOX

emissions of the nine-county DFW area for a specific day modeled in the 2006 episode. The 

tileplot is used to graphically QA the modeled emissions. Reported on the tile plots are the 

emissions totals by county in the lower left hand corner and the corresponding diurnal profile of 

the sources in the lower right corner of the graphic. The colored/shaded tiles represent the 

quantity of emissions within that grid cell. A colored/shaded tile represents the ARD EGU NOX

tons for a modeled day’s 4 km-by4 km grid cell within the DFW nine-county area.
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Figure 1: Tileplot of DFW ARD NOX Emissions for 06 June 2006

2.1.1.6 2006 Tank Landing Loss (TLL) Survey in HGB

As a result of a Texas Air Quality Study II (TexAQS II) remote sensing VOC project in July 2005, 

large storage tanks in specific service (e.g., tanks-for-hire at terminal facilities and crude oil 

breakout stations) in the Houston Ship Channel (HSC) area were found to be landing their 

floating roofs (internal and external) on the tank legs and not reporting those vapor space losses. 

As a result, a TCEQ Chapter 115 rule was written that limits the number of permissible 

convenience roof landings. Additional details about the under-reported VOC emissions and 

data development for modeling are in the March 2010 HGB Appendix B, Section 2.1.1.7.

For this SIP revision, the baseline average hourly TLL VOC emissions used are the same as those

modeled and described in March 2010 HGB Appendix B, Sections 2.2.1.2.
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2.1.1.7 Emissions Inventory Reconciliation in HGB (aka, HRVOC Reconciliation, Extra 

Olefins)

EI Reconciliation is the process by which the reported EI is adjusted so that modeled emissions 

more closely match the VOC concentrations measured during the episodes. TexAQS II 

confirmed the need for this, as TexAQS 2000 first affirmed. VOC, and especially HRVOC, 

continue to be under-reported in the annual EIQs, according to monitors and aircraft 

measurements.

In previous SIP revisions, the TCEQ generated an “extra olefins” file to add to the modeling EI 

to account for the under-reporting. The details of this Potential Source Contribution Function 

(PSCF) technique are provided in March 2010 HGB Appendix B, Attachment 1: Reconciling 

Reported VOC Emissions with Ambient Measurements. The reconciled extra emissions were

placed at a single pseudo point in each affected modeling cell, in modeling cells that contain 

point sources, and assigned an emission rate for each HRVOC to best offset the difference 

between modeled and calculated concentrations. A new VOC AFS record was created for each 

pseudo point source. The pseudo point source was placed in the middle of each affected cell and 

assigned default stack parameters (e.g., 5.0 meter stack height). Since these reconciled points 

do not exist in the STARS database, unique plant, stack and point identifiers were assigned to 

new speciation cross reference and profile files. The profiles were individually determined 

during the PSCF procedure, and EPS3 processing was performed for these data separately. The 

PSCF version 3 file used in the March 2010 HGB SIP was used in this modeling.

2.1.2

This section and its subsections discuss the point source modeling emissions development for all 

areas outside of Texas within the modeled CAMx domain. The modeled Regional area includes 

the following parts:

Regional (Outside of Texas) Point Sources

• Oklahoma, Arkansas, and Louisiana (three adjacent states within the modeling domain);

• Remaining U.S. (within the modeling domain);

• Offshore (Gulf of Mexico);

• Mexico; and

• Canada.

The level of detail applied to the development of the modeling emissions decreases with distance 

from Texas, in general. Each region was modeled using a different source of EI data.

2.1.2.1 States Adjacent to Texas

The states adjacent to Texas within the modeling domain include Oklahoma, Arkansas, and 

Louisiana. The TCEQ contacted each to obtain point source emissions data files representative 

of June 2006.

Emissions data from other states are generally reported as annual emissions, whereas the Texas 

STARS emissions can be extracted as average OSD. Ozone season data were used, if provided. 

When only annual data were provided, daily emission records were generated from the annual 

data, to be consistent with other datasets. 

For this SIP revision, the TCEQ used the same adjacent states point source files that were used 

for the March 2010 HGB SIP: Louisiana Department of Environmental Quality (LDEQ) 2004 

point source annual emissions inventory, and Oklahoma of Environmental Quality (ODEQ) and 

Arkansas Department of Environmental Quality (ADEQ) 2005 point source annual emission 
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inventories. The March 2010 HGB Appendix B, Section 2.1.2.1, describes the data and processes 

used.

2.1.2.1.1 Hourly Acid Rain Substitution

The TCEQ replaced the original emission records with hourly records for all the Acid Rain EGUs 

in the adjacent states, as well as the nation by matching the ARD identifiers, ORISPL and Unit

ID. The AFS records that the LDEQ supplied did not have the acid rain identifiers, so the 2002 

NEI was used as the cross reference.

The TCEQ downloaded all of the hourly acid rain data from EPA’s CAMD query website. 

Because the 2002 NEI was used for EGU identifiers for Louisiana, the 2006 CAMD queries 

included some new EGUs (i.e., post 2002). For these new units, the TCEQ was able to manually 

match some of the new EGUs by site name. For the remainder, the TCEQ created AFS records 

and assigned new EGUs with default stack parameters to the nearest town. The corresponding 

hourly VOC and CO records for matched EGUs were generated using their VOC-to-NOX and COto-NOX ratios. For unmatched points in each state, the TCEQ used VOC and CO ratios larger 

than roughly two-thirds of the ratios across the state to calculate hourly VOC and CO records. 

This procedure resulted in a daily OSD AFS file for each state and an hourly ARD AFS file for 

each state. The TCEQ compared AFS emission totals to the ARD for each state, making sure all 

emissions for each were assigned to points within each state. Next, the TCEQ compared AFS 

and ARD emissions for each day of the episode to make sure that all of the emissions were 

distributed over the entire episode

ARD NOX emissions for the adjacent states for a specific episode day modeled in 2006 are 

shown in:

• Figure 2: Tileplot of Louisiana ARD NOX Emissions for 14 June 2006, 

• Figure 3: Tileplot of Arkansas ARD NOX Emissions for 14 June 2006, and

• Figure 4: Tileplot of Oklahoma ARD NOX Emissions for 14 June 2006.
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Figure 2: Tileplot of Louisiana ARD NOX Emissions for 14 June 2006
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Figure 3: Tileplot of Arkansas ARD NOX Emissions for 14 June 2006
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Figure 4: Tileplot of Oklahoma ARD NOX Emissions for 14 June 2006

2.1.2.2 Remaining States in Modeling Domain

The 2006 EI for the remaining states within the modeling domain were developed from 2002 

data files provided by the CenRAP and included all of the RPOs data for the nation, as used for 

Regional Haze SIP modeling. The TCEQ received the inventory data from CenRAP on a hard 

drive in Inventory Data Analyzer (IDA) format, a format suitable for Sparse Matrix Operator 

Kernel Emissions (SMOKE) processing. The TCEQ extracted the “final 2002 Base g Typical 

(typ02f)” annual emissions data. Emissions were reported as typical for 2002 and were grown 

to 2006. The TCEQ used EPA’s EGAS5 growth factors with a FIPS SCC configuration as was 

performed for the adjacent states. An AFS-formatted file including all necessary and relevant 

modeling parameters was produced for EPS3 processing. Resulting ARD NOX emissions for the 

remaining states for a specific episode day modeled in 2006 are shown in Figure 5: Tileplot of 

Remaining States ARD NOX Emissions for 14 June 2006.
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Figure 5: Tileplot of Remaining States ARD NOX Emissions for 14 June 2006

Details on AFS file creation from the RPO files, including QA, Acid Rain substitution, speciation 

and temporal allocation, are available in the March 2010 HGB Appendix B, Section 2.1.2.2.

2.1.2.3 Offshore Point Sources

The TCEQ obtained the 2005 GWEI, developed by Eastern Research Group (ERG) under 

contract to the Minerals Management Service (MMS). This was a significant update to the 2000 

GWEI modeled in previous SIP revisions. The report and data are divided into two parts, oil 

and gas exploration and production platform (point) sources and non-platform (area) sources. 

The TCEQ obtained the 2005 GWEI data and documentation from MMS in Microsoft Access 

(zipped) and PDF format, respectively. These can be downloaded from the MMS webpage, 

http://www.gomr.mms.gov/homepg/regulate/environ/airquality/gulfwide_emission_inventor

y/2005GulfwideEmissionInventory.html. The offshore emissions are illustrated in Figure 6: 
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Tileplot of Offshore NOX for a representative June day and Figure 7: Tileplot of Offshore VOC 

for a representative June day.

The March 2010 HGB Appendix B, Section 2.1.2.3 discusses the formatting of the data, QA, 

justification for using June 2005 as representative data, and creation of temporal profiles.

Figure 6: Tileplot of Offshore NOX for a representative June day
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Figure 7: Tileplot of Offshore VOC for a representative June day

2.1.2.4 Mexican Point Sources

The TCEQ used the data from Phase III of the 1999 Mexico NEI, which is the most current data 

used by EPA and the RPOs. The TCEQ downloaded the NIF format versions of the files from 

http://www.epa.gov/ttn/chief/net/mexico.html and parsed the files into AFS files.
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The 1999 data were used for the 2006 episode without growth because there is no information 

on growth and controls for Mexican point sources. No temporal allocation or speciation data 

were available, so defaults were used. 

Figure 8: Tileplot of representative Mexican OSD NOX and Figure 9: Tileplot of representative 

Mexican OSD VOC are tileplots of Phase III of the 1999 Mexico NEI for a representative OSD.

Figure 8: Tileplot of representative Mexican OSD NOX
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Figure 9: Tileplot of representative Mexican OSD VOC

2.1.2.5 Canadian Point Sources

In the CAIR 2001 base case modeling, the EPA used a Canadian point source dataset based on a 

1995 Canadian EI. These are the most recent Canadian emissions data available. The TCEQ 

extracted these data from EPA’s IDA-formatted SMOKE data files and converted them to AFS 

records for further processing with EPS3. The only part of Canada within the modeling domain 

is the southern part of Ontario province.

The TCEQ used these data for the 2006 episode without adjustment for growth or controls. No 

temporal allocation or speciation data were available, so defaults were used. This is the same 

Canadian dataset used for modeling in the March 2010 HGB Appendix B, Section 2.1.2.5.
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2.1.3

CAMx provides the option to model selected point sources with a PiG algorithm. NOX reaction 

chemistry is enhanced by treating these selected point source plumes as Lagrangian puffs. The 

TCEQ uses the GREASD PiG option in CAMx, which is most applicable to large NOX plumes. 

The GREASD PiG option was used for all point sources that met the criteria in

Plume-in-Grid (PiG) Source Selection

Table 5: 

Summary of PiG Thresholds Chosen.

Table 5: Summary of PiG Thresholds Chosen

Modeled Area NOX Threshold (tpd)

Texas 5.0

Adjacent States (LA, AR, OK) & Mexico 7.5

Next ring of States (MS, etc) 10.0

Next distant ring of States (AL, etc) 15.0

Other States, Canada & Offshore 25.0

The NOX threshold of 5.0 tons per day (tpd) in Texas denotes that any individual stack or colocated group of nearby stacks that totaled 5.0 or more tpd of NOX emissions on an episode day 

were tracked as a PiG source. If multiple stacks were close enough together for their plumes to 

merge (within 200 meters of each other), and the aggregate NOX emission rate for the cluster 

exceeded the threshold value, a new source was created with the combined NOX emission rate of 

the cluster, and this source was flagged for PiG treatment. The stack parameters of the new 

source became an average of the stack parameters of all of the sources in the cluster. The TCEQ 

modeled both individual PiGs and combined PiGs within each of the modeled areas of Table 5. 

The EPS3 module, PiGEMS, provides a summary of the PiG treatment. There were a total of 255 

PiG sources chosen for the entire domain, 212 of which are co-located combined new stacks.

2.1.4

Snapshots of the point source emission files processed with EPS3 for CAMx in each episode are 

presented in 

Summary of June 2006 Base Case Point Sources

Table 6: Base Case AFS File for the DFW June 2006 Episode. The version number 

on each dataset indicates a change from the previous version (e.g., “v8”). The regional AFS file 

for the GWEI contains monthly emissions for June only and the regional AFS file for Canadian 

emissions contains annual emissions. The FTP download site for these files (or their successors)

is ftp://amdaftp.tceq.texas.gov/pub/DFW8H2/ei/basecase/point/.

Table 6: Base Case AFS File for the DFW June 2006 Episode

Area AFS Point Source Emissions File Hourly Daily Special

Texas afs.osd_2006_STARS_extract_for_31May_ard_episode.v4 X

Texas afs.ard_31May_to_02Jul06_TX_episode_v5 X

Texas afs.aggVOC_extra_alkenes_for_2006_v3 X

Texas afs.landing_losses_3Q06_aver_day_episode_v1 X

Regional USA_osd_2006_for_3Q06_generic_from_2006CENRAP.v2 X

Regional afs.USA_regional_ard_sansTX_31May_to_02Jul06_episode_v2 X

Regional afs.gwei2005.May_Oct_edit.3pol.lcp Monthly

Regional afs.Mexico_from_updated_1999_NEI.lcp_3pols_v1 X

Regional afs.CAIRCanada.2001.v1a.latlong.lcp Annual
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The TCEQ chose the second Wednesday of the June 2006 episode as a representative day for

reporting base case emissions totals. Table 7: 2006 DFW Base Case Episode Day (June 14, 

2006) Emissions Summary summarizes emissions for that day.

Table 7: 2006 DFW Base Case Episode Day (June 14, 2006) Emissions Summary

Emissions Source

DFW 

NOX

(tpd)

DFW 

VOC 

(tpd)

TX minus 

DFW

NOX (tpd)

TX minus 

DFW

VOC (tpd)

U.S. minus 

TX NOX

(tpd)

U.S. minus 

TX VOC 

(tpd)

Non-EGUs (OSD) 41.6 40.0 703.1 562.3 7645 3331

EGUs (ARD) 7.6 0.7 516.7 32.7 6156 46

Tank Landing Losses 6.6

HRVOC Reconciliation 19.3

2.2 2006 Baseline Point Source Modeling Emissions Development

The 2006 point source emissions used in the base case are specific to individual days and hours, 

for the Acid Rain EGU portion of the EI. For the baseline case, the TCEQ created files that 

represent a typical ozone season (summer) day in 2006. The subsections that follow discuss 

how the baseline emissions differ from the base case.

2.2.1

2.2.1.1 Ozone Season Daily (OSD)

Texas Point Sources

The OSD point source emissions for the typical 2006 baseline day are the same as the 2006 base 

case OSD emissions, as these are the average OSD emissions extracted from STARS.

Table 8: 2006 Baseline OSD Emissions in Texas shows the modeled ozone precursor 2006 

baseline totals for point sources in the DFW nine-county nonattainment area (NAA), HGB, and 

the rest of Texas.

Table 8: 2006 Baseline OSD Emissions in Texas

Area NOX

#points

NOX 

tpd

VOC 

#points

VOC 

tpd

DFW 1,535 41.61 4,810 39.95

HGB 5,194 125.39 26,343 196.28

Rest of TX 10,168 577.75 30,380 365.97

Some points in Texas are outside the modeling domain, for example, points in west Texas. The 

“#points” entry in Table 8 is the total number of point sources in that area. Emissions were

summed within the area to give the area emissions total. The TCEQ typically eliminates zero 

emissions records, and the EPS3 processor drops VOC records with zero emissions because they

do not have a speciation cross reference.

2.2.1.2 Hourly Acid Rain Data (ARD) Point Sources

To develop an Acid Rain EGU baseline, the TCEQ averaged the Acid Rain NOX for each hour of 

the day for each unit for the third quarter of 2006 (July 1 through September 30). These data 

records represent the typical ozone season day that maintains the temporal profile of the 

individual units. Corresponding hourly average CO and VOC emissions were calculated from 

STARS OSD, stack-specific emissions by multiplying CO:NOX and VOC:NOX ratios by the hourly 
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NOX rate for each acid rain unit. The approach is consistent with what was modeled for the EGU 

baseline for the March 2010 HGB SIP revision. A summary of the ARD emissions for the state is

presented in Table 9: 2006 Baseline Hourly Texas Acid Rain EGU Emissions. The tabulated 

hourly emissions values are the sum of emissions for all point sources in each NAA and the 

remainder of the state, although some of the point sources in the attainment areas of Texas are 

outside of the modeling domain. All hourly values were rounded to two decimal places.

Table 9: 2006 Baseline Hourly Texas Acid Rain EGU Emissions

Hour

DFW 

NOX

tph

DFW 

VOC 

tph

DFW 

CO 

tph

HGB 

NOX

tph

HGB 

VOC 

tph

HGB 

CO 

tph

Rest 

of TX 

NOX

tph

Rest 

of TX 

VOC 

tph

Rest 

of TX 

CO 

tph

1 0.24 0.02 0.11 1.51 0.10 1.13 17.34 0.88 32.13

2 0.22 0.02 0.10 1.47 0.10 1.12 16.63 0.84 31.62

3 0.21 0.02 0.10 1.45 0.10 1.10 16.28 0.82 31.29

4 0.21 0.02 0.09 1.45 0.10 1.11 16.31 0.82 31.36

5 0.23 0.02 0.10 1.58 0.11 1.25 17.07 0.89 31.56

6 0.21 0.02 0.10 1.56 0.10 1.19 16.84 0.90 31.26

7 0.21 0.02 0.10 1.59 0.11 1.19 18.77 1.07 32.75

8 0.25 0.02 0.12 1.59 0.11 1.20 18.12 0.98 32.89

9 0.33 0.02 0.15 1.69 0.11 1.25 19.00 1.05 33.71

10 0.36 0.03 0.17 1.84 0.12 1.35 19.94 1.10 34.42

11 0.40 0.04 0.20 2.07 0.14 1.54 20.86 1.13 34.96

12 0.45 0.05 0.25 2.32 0.15 1.77 22.01 1.17 35.38

13 0.53 0.06 0.31 2.60 0.17 2.04 23.30 1.20 35.73

14 0.58 0.06 0.34 2.74 0.18 2.17 24.52 1.24 36.01

15 0.63 0.07 0.37 2.83 0.18 2.25 25.52 1.28 36.44

16 0.63 0.07 0.38 2.81 0.18 2.23 25.97 1.30 36.65

17 0.61 0.06 0.36 2.75 0.18 2.13 25.34 1.27 36.43

18 0.55 0.06 0.32 2.59 0.16 1.91 24.12 1.23 36.02

19 0.49 0.05 0.29 2.39 0.15 1.74 22.75 1.19 35.56

20 0.45 0.05 0.27 2.26 0.15 1.69 21.98 1.15 35.23

21 0.41 0.04 0.23 2.09 0.14 1.57 21.14 1.12 34.88

22 0.37 0.03 0.19 1.80 0.12 1.36 20.30 1.08 34.56

23 0.30 0.03 0.15 1.64 0.11 1.24 19.11 1.02 33.83

24 0.27 0.02 0.13 1.56 0.11 1.19 18.12 0.96 32.98

TOTALS 9.14 0.88 4.93 48.20 3.18 36.70 491.34 25.71 817.65

#points 49 74 248 49 74 248 49 74 248

2.2.1.3 Tank Landing Loss (TLL) Survey

The 2006 baseline for floating roof TLL surveys was calculated as the average of the hourly 

emissions for each tank point source of the survey for all of the modeled episode days of 2006. 

This average was used for both the base case and baseline modeling. Details about these sources

are available in the March 2010 HGB Appendix B, Section 2.2.1.4.
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2.2.1.4 Emissions Inventory Reconciliation in HGB (aka, HRVOC Reconciliation, Extra 

Olefins)

The 2006 HRVOC Reconciliation emissions remain unchanged from the 2006 base case.

2.2.1.5 2006 Baseline Tileplots for Texas

Following are tileplots of 2006 baseline modeling emissions. Included are:

• Figure 10: DFW Elevated NOX

• Figure 11: DFW Elevated VOC

• Figure 12: DFW Low-level NOX

• Figure 13: DFW Low-level VOC

• Figure 14: HGB HRVOC Reconciliation

• Figure 15: HGB Tank Landing Losses VOC

The elevated and low-level tileplots show the DFW nine-county area, whereas the HGB-BPA gulf 

area can be seen in the TLL and HRVOC plots.
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Figure 10: DFW Elevated NOX
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Figure 11: DFW Elevated VOC
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Figure 12: DFW Low-level NOX
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Figure 13: DFW Low-level VOC
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Figure 14: HGB HRVOC Reconciliation
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Figure 15: HGB Tank Landing Losses VOC

2.2.2

2.2.2.1 Adjacent States and Regional States Non-Acid Rain

Outside Texas

The TCEQ used the 2006 OSD (or calculated average day if only annual emissions were 

provided) base case records for the non-ARD 2006 baseline for states outside of Texas. For the 

three adjacent states, these data were from the 2006 base case with the Acid Rain units 

removed. For the regional states, the 2006 baseline was the base data (2002 CENRAP/RPO) 

grown to 2006 with the Acid Rain units removed.

Table 10: 2006 Baseline Emissions Summary for Non-ARD Points Outside of Texas summarizes 

the non-Acid Rain emissions for the 2006 baseline. The photochemical model may not use all of 

the records in the non-Acid Rain 2006 base case, since some states have a fraction of their area 
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outside of the modeling domain (e.g., the Oklahoma panhandle). EPS3 processing drops these 

from the modeling EI.

Table 10: 2006 Baseline Emissions Summary for Non-ARD Points Outside of Texas

STATE # NOX

Points NOX tpd # VOC Points VOC tpd

Arkansas 1,036 82.14 2,063 101.00

Louisiana 4,090 658.30 7,538 234.24

Oklahoma 2,338 216.33 5,425 107.46

Other States, outside Texas 78,431 6687.87 159,614 2888.52

2.2.2.2 Adjacent States and Regional States Hourly Acid Rain

The 2006 baseline for the ARD sources of the other states is a calculated typical summer day 

with hourly emissions that are the average for each Acid Rain point source during the third 

quarter (July 1 through September 30) of 2006. VOC and CO emissions for each hour of the 

typical summer day come from the hourly NOX emissions and the VOC:NOX and CO:NOX ratios, 

computed from the daily emissions data for each Acid Rain point.

Table 11: 2006 Baseline Hourly Emissions Summary for ARD Points Outside of Texas

summarizes the 2006 baseline Acid Rain emissions within the TCEQ regional modeling domain 

outside of Texas. The peak hours of emissions, coinciding with peak electrical demand, for the 

Acid Rain EGUs are between hours 14 and 16. Only a fraction of the point source emissions in 

some states is modeled if part of that state is outside the modeling domain, e.g., parts of western 

Kansas.

Table 11: 2006 Baseline Hourly Emissions Summary for ARD Points Outside of 

Texas

Hour

AR 

NOX

tph

LA 

NOX

tph

OK 

NOX

tph

Rest of 

U.S.

NOX tph

AR 

VOC 

tph

LA 

VOC 

tph

OK 

VOC 

tph

Rest of 

U.S. VOC 

tph

1 4.60 6.16 9.16 212.40 0.06 0.12 0.11 1.33

2 4.31 5.99 8.82 203.02 0.05 0.12 0.11 1.27

3 4.04 5.91 8.63 196.78 0.05 0.11 0.10 1.22

4 3.98 5.90 8.55 195.59 0.05 0.11 0.10 1.21

5 4.09 6.04 8.79 202.39 0.05 0.12 0.11 1.26

6 4.23 6.38 8.97 214.08 0.05 0.12 0.11 1.35

7 4.40 6.44 9.18 223.93 0.06 0.12 0.12 1.42

8 4.88 6.54 9.48 236.27 0.07 0.13 0.12 1.51

9 5.15 6.69 9.96 249.91 0.07 0.13 0.13 1.62

10 5.24 6.88 10.67 261.96 0.07 0.13 0.13 1.71

11 5.14 7.37 11.46 270.53 0.07 0.14 0.15 1.79

12 5.19 7.78 12.22 276.32 0.07 0.15 0.16 1.85

13 5.19 8.30 12.90 280.17 0.07 0.17 0.16 1.89

14 5.24 8.60 13.42 282.40 0.07 0.17 0.17 1.92

15 5.25 8.71 13.62 283.57 0.07 0.18 0.17 1.94

16 5.21 8.63 13.85 283.84 0.07 0.17 0.18 1.93
B-38

Hour

AR 

NOX

tph

LA 

NOX

tph

OK 

NOX

tph

Rest of 

U.S.

NOX tph

AR 

VOC 

tph

LA 

VOC 

tph

OK 

VOC 

tph

Rest of 

U.S. VOC 

tph

17 5.14 8.30 13.60 282.80 0.07 0.17 0.17 1.91

18 5.08 7.88 13.10 279.06 0.07 0.16 0.17 1.87

19 4.95 7.53 12.45 275.43 0.06 0.15 0.16 1.82

20 5.00 7.30 12.09 274.55 0.07 0.15 0.15 1.80

21 4.85 6.95 11.66 269.02 0.06 0.14 0.15 1.74

22 4.69 6.67 10.95 256.44 0.06 0.13 0.14 1.64

23 4.68 6.50 10.31 240.88 0.06 0.12 0.13 1.53

24 4.71 6.39 9.70 224.86 0.06 0.12 0.12 1.42

TOTALS 115.23 169.84 263.54 5976.20 1.51 3.33 3.30 38.94

#points 43 96 75 1,351 43 96 75 1,351

2.2.2.3 Offshore, Mexico, and Canada

The Offshore 2005 GWEI, the 1999 Mexican NEI, and the 1995 Canadian baseline point source 

files are the same as the base case files, since they are already being modeled as an average day.

2.2.3

The point source emission files that were processed with EPS3 for CAMx for the baseline 

(typical summer day) are presented in 

Summary of 2006 Baseline Point Sources

Table 12: AFS Files for the 2006 Baseline. The regional 

AFS file for the GWEI contains monthly emissions for June only and the regional AFS file for 

Canadian emissions contains annual emissions. The version number on each dataset indicates a

change from the previous version (e.g., “v2”). The FTP download site for the point source files 

or their successors is ftp://amdaftp.tceq.texas.gov/pub/DFW8H2/ei/baseline/point

Table 12: AFS Files for the 2006 Baseline

Area AFS Point Source Emissions File Hourly Daily Special

TEXAS afs.ard_generic_episode_3Q06_aver_day.vDFW1 X

TEXAS afs.osd_2006_STARS_extract_for_31May_ard_episode.v4 X

TEXAS afs.landing_losses_3Q06_aver_day_episode_v1 X

TEXAS afs.aggVOC_extra_alkenes_for_2006_v3 X

REGIONAL afs.USA_mTX_ard_3Q06_aver_day.vDFW1 X

REGIONAL USA_osd_2006_for_3Q06_generic_from_2006CENRAP.v2 X

REGIONAL afs.gwei2005.May_Oct_edit.3pol.lcp Monthly

REGIONAL afs.Mexico_from_updated_1999_NEI.lcp_3pols_v1 X

REGIONAL afs.CAIRCanada.2001.v1a.latlong.lcp Annual

Table 13: 2006 Baseline Point Source Emissions Summary summarizes the baseline emissions. 

These tabulated emissions are AFS totals input to EPS3. CAMx input values may differ. The TX 

minus DFW column includes some points in Texas outside the modeling domain. The U.S. 

minus TX column includes some points outside the modeling domain.
B-39

Table 13: 2006 Baseline Point Source Emissions Summary

Emission Source

DFW 

NOX

(tpd)

DFW 

VOC 

(tpd)

TX minus 

DFW 

NOX (tpd)

TX minus 

DFW 

VOC (tpd)

U.S. minus 

TX NOX

(tpd)

U.S. minus 

TX VOC 

(tpd)

NEGUs (OSD) 41.6 40.0 703.1 562.2 7645 3331

EGUs (ARD) 9.1 0.9 539.6 28.9 6525 47

Tank Landing Losses 6.5

HRVOC Reconciliation 19.3

2.3 2012 Future Year Point Source Modeling Emissions Development

This section describes the development of the 2012 future year point source EI. The eight-hour 

ozone attainment date for an area classified as Serious is June 15, 2013. The modeled 

attainment year is 2012, the ozone season prior to the attainment date.

The baseline emissions are projected, i.e. they are grown to the attainment year and on-thebooks controls (those that will be in place after the baseline year and prior to the attainment 

year) are applied. The on-the-books controls are controls for which enforceable emissions 

reductions rules have been written already; they are not additional proposed rules that result 

from this SIP revision. Proposed rules would be modeled in a 2012 control strategy EI or as part 

of Reasonably Available Control Measure (RACM) analyses. The 2012 future base EI provides 

the basis to determine if attainment has been reached and is the starting point for any 2012 

control strategy testing, if required.

This future year baseline point source EI has been projected from the 2006 point source 

baseline EI, with the exception of the Texas EI.

2.3.1

The attainment areas of Texas include all of Texas except DFW and HGB. The subsections 

below address growth and controls separately.

Attainment Areas of Texas

2.3.1.1 Attainment Area 2012 Growth Projections

Different growth projection techniques were applied to the EGUs that have Acid Rain data 

(ARD) versus the non-EGUs (NEGUs). The techniques used are similar to EPA and RPO 

projection methods for modeling future cases.

2.3.1.1.1 EGUs

To develop the Acid Rain EGU 2008 baseline, the TCEQ averaged the Acid Rain NOX for each 

hour of the day for each unit for the third quarter of 2008 (3Q2008). The TCEQ chose this 

dataset from which to project because it is newer and contains more of the actual emissions 

growth from newer units. Not all EGUs are Acid Rain sources and not all NOX point sources at 

EGU facilities are Acid Rain sources. The non-Acid Rain EGUs were modeled at their 2008

emissions along with the NEGU point sources.

The complete set of 2012 EGUs consists of the 3Q2008 ARD EGUs, the 2008 non-Acid Rain 

EGUs, and post-2008 EGUs that have approved TCEQ permits. As with previous SIP revisions, 

the TCEQ assumes that the EGU growth in the state comes from the TCEQ newly-permitted 

EGUs.
B-40

2.3.1.1.2 Newly-Permitted EGUs

Growth in EGUs in Texas is accomplished with the addition of all newly-permitted EGUs since 

the baseline, all within the constraint of the EPA’s Clean Air Interstate Rule (CAIR), described in 

the controls subsection below. This subsection describes the procedures for developing the 

newly-permitted EGU EI.

Texas EGU emissions for 2012 were developed by researching and compiling data from various 

sources. These sources include:

• Electric Reliability Council of Texas (ERCOT): http://www.ercot.com/;

• TCEQ air permitting projects with combustion turbines,

http://www.tceq.state.tx.us/assets/public/permitting/air/memos/turbine_lst.pdf; and

• TCEQ New Source Review Permits Information Management System (NSRP IMS) internal 

document server for newly-permitted EGU data.

Information from these sources includes individual units’ disposition (i.e., operating status), 

new units coming online, units to be mothballed, units to be shut down and retired, and units 

that are proposed to be operational by the end of ozone season in 2012 because they applied for, 

and were granted, a TCEQ air permit. The TCEQ assumed that by ozone season 2012, all 

current mothballed and reliability-must-run (RMR) units would be retired. For new units 

planned to come online, a distinction is made between those that have received a permit and

those that have pending permits. All data sources were reconciled to ensure all units were 

accounted for, and that their status as of December 2010 was modeled. As the most recent EGU 

emissions data for modeling is from 3Q2008 Acid Rain, new EGUs are based on additions and 

changes subsequent to 2008. For the two years between December 2010 and December 2012, 

there is ample generation proposed from the newly permitted units to meet the projected 

demand in electricity.

For the newly-permitted EGUs, emissions were calculated based on the permit Maximum 

Allowable Emission Rates Table (MAERT). Pollutants acquired from the permits were NOX, 

VOC, and CO. The method of determining the allowable emissions differs based on the type of 

unit and its primary purpose for being constructed. For example, coal plants may have a 30-day 

rolling average emission rate, while gas turbines may have a short term allowable emission rate 

in pounds per hour (pph) and/or a long term allowable emission rate in tons per year (tpy). In 

some cases, a unit may have a combination of the above, in addition to maintenance, startup 

and shutdown (MSS) emission limits.

When available, the 30-day pph emissions limitation was used. These were most often available 

for solid fuel-fired units. This time frame represents a good compromise between the standard 

short-term allowable, which sometimes includes MSS, and the standard long-term permit 

allowable. The short term allowable in pph, when converted to tpd, is often substantially more 

than a unit would realistically emit in any day; the long-term allowable in tpy, when converted 

to tpd, may under-represent what a unit could emit during any one day, especially during a 

summer day during the ozone season.

MSS permitting has been phasing in for several years. These activities help provide a more 

realistic operating scenario than the maximum of the short-term or long-term emission rates. 

This is especially important for those units that have many MSS events during a typical summer, 

such as the peaking units, which operate only during the peak demand times. MSS limits vary 

between permits on how they are represented. Examples of permitted MSS and how they are 

modeled are available in the March 2010 HGB Appendix B, Section 2.3.1.1.1.
B-41

The emission rates calculated represent worst case for some units, but for most, they represent a 

typical summer day during the ozone season, corresponding to some of the highest days of 

electricity demand. In developing a future EI, the TCEQ has historically modeled only those 

units that (1) have been issued a permit, and (2) are expected to be operational prior to the 

attainment date. The complete list of newly-permitted EGUs added as the EGU growth in the 

state sorted by area is provided as Table 14: Newly Permitted EGUs (post 2008) in Texas as of 

December 2010.

Table 14: Newly Permitted EGUs (post 2008) in Texas as of December 2010

Area Sitename County

Permit 

NOX 

(tpd)

Permit 

VOC 

(tpd)

Permit 

CO 

(tpd)

Modeled 

CAIR 

NOX

(tpd)

Operating 

in 2008

BPA Hardin Facility Hardin 0.430 0.118 0.804 0.057 Y

BPA Hardin Facility Hardin 0.430 0.118 0.804 0.725 Y

CC Barney M Davis Nueces 1.251 0.466 6.094 0.090 Y

CC Barney M Davis Nueces 1.251 0.466 6.094 0.090 Y

ELP Newman Unit 6 El Paso 1.422 0.216 5.064 0.091 Y

ELP Newman Unit 6 El Paso 1.422 0.216 5.064 0.091 Y

ELP Global Alternative El Paso 0.683 0.186 0.419 0.091 Y

ETX Lufkin Generating Pl Angelina 0.624 0.084 0.624 0.066

ETX Panda Temple Power Bell 0.454 0.599 5.782 0.048

ETX Panda Temple Power Bell 0.454 0.599 5.782 0.048

ETX Panda Temple Power Bell 0.454 0.599 5.782 0.048

ETX Panda Temple Power Bell 0.454 0.599 5.782 0.048

ETX Dansby Power Plant Brazos 0.298 0.032 1.027 0.031

ETX E.S. Joslin Power St Calhoun 2.232 0.156 4.776 0.235

ETX Formosa Pt.Comfort Calhoun 1.260 0.096 1.980 0.133

ETX Formosa Pt.Comfort Calhoun 1.260 0.096 1.980 0.133

ETX Pattillo Branch Fannin 0.865 0.333 3.870 0.044 Y

ETX Pattillo Branch Fannin 0.865 0.333 3.870 0.044 Y

ETX Pattillo Branch Fannin 0.865 0.333 3.870 0.034 Y

ETX Pattillo Branch Fannin 0.865 0.333 3.870 0.034 Y

ETX Winchester 

PowerPark

Fayette 0.109 0.045 0.499 0.078 Y

ETX Winchester 

PowerPark

Fayette 0.109 0.045 0.499 0.192 Y

ETX Winchester 

PowerPark

Fayette 0.109 0.045 0.499 0.192 Y

ETX Winchester 

PowerPark

Fayette 0.109 0.045 0.499 0.057 Y

ETX Lamar Power Partners Lamar 0.545 0.101 0.894 0.324 Y

ETX Lamar Power Partners Lamar 0.545 0.101 0.894 0.132 Y

ETX Madison Bell Partner Madison 1.000 0.129 2.096 0.132 Y

ETX Madison Bell Partner Madison 1.000 0.129 2.096 0.132 Y

ETX Madison Bell Partner Madison 1.000 0.129 2.096 0.078 Y
B-42

Area Sitename County

Permit 

NOX 

(tpd)

Permit 

VOC 

(tpd)

Permit 

CO 

(tpd)

Modeled 

CAIR 

NOX

(tpd)

Operating 

in 2008

ETX Madison Bell Partner Madison 1.000 0.129 2.096 0.908 Y

ETX Sandy Creek McLennan 6.876 0.348 29.472 0.132 Y

ETX Sandow 5 Milam 3.552 0.180 3.552 0.031 Y

ETX Sandow 5 Milam 3.552 0.180 3.552 0.031 Y

ETX Nacogdoches Power Nacogdoches 1.649 0.240 2.724 0.090 Y

ETX Nacogdoches Power Nacogdoches 3.072 0.336 2.628 0.090 Y

HGB Green Power Unit 1 Brazoria 0.137 0.074 0.802 0.014

HGB Green Power Unit 1 Brazoria 0.137 0.074 0.802 0.014

HGB Dow Chemical Cogen Brazoria 0.658 0.657 4.316 0.069

HGB NRG Cedar Bayou Chambers 0.570 0.198 6.217 0.013 Y

HGB NRG Cedar Bayou Chambers 0.570 0.198 6.217 0.013 Y

HGB Cedar Bayou Chambers 0.692 0.151 6.503 0.073

HGB Cedar Bayou Chambers 0.766 0.151 6.503 0.081

HGB Deer Park Energy 

Center

Harris 0.417 0.872 6.679 0.105 Y

HGB Deer Park Energy 

Center

Harris 0.417 0.872 6.679 0.105 Y

HGB TECO Central Plant Harris 0.321 0.104 1.630 0.105 Y

HGB TECO Central Plant Harris 0.321 0.104 1.630 0.105 Y

HGB Lewis Creek Montgomery 0.271 0.087 1.066 0.015 Y

HGB Lewis Creek Montgomery 0.271 0.087 1.066 0.015 Y

SAN J K Spruce Unit 2 Bexar 6.624 0.348 53.760 0.699

SAN VH Braunig 5 Bexar 0.321 0.042 1.432 0.034

SAN VH Braunig 6 Bexar 0.321 0.042 1.432 0.034

SAN VH Braunig 7 Bexar 0.321 0.042 1.432 0.034

SAN VH Braunig 8 Bexar 0.321 0.042 1.432 0.034

WTX La Palma Power Sta Cameron 0.741 0.189 4.823 0.078

WTX Quail Run Energy 

Center

Ector 0.127 0.042 0.559 0.072 Y

WTX Quail Run Energy 

Center

Ector 0.127 0.042 0.559 0.091 Y

WTX J L Bates Power Sta Hidalgo 0.737 0.190 5.387 0.029 Y

WTX Jack Co Gen Facility Jack 1.824 0.532 7.672 0.029 Y

WTX Jack Co Gen Facility Jack 1.824 0.532 7.672 0.174 Y

Table 14 includes (1) the calculated NOX, VOC and CO emissions from permit applications and 

MAERTs, representing realistic (not absolute worst-case and not absolute best-case) average 

day emissions, and (2) the NOX emission rates after incorporating the existing rules that apply 

to ARDs (CAIR Phase I for the whole state and MECT in HGB). The TCEQ assumed NOX

controls, offsets, or credit purchases will be used to meet these NOX emissions rates. VOC and 

CO rates are modeled at their permitted levels and represent the worst case.
B-43

The 2010 CAIR allocations assigned by the TCEQ were applied to all EGUs, including the newlypermitted EGUs, which received their share of the 9.5 percent set-aside. Some of these newlypermitted EGUs had already begun operation and had been assigned CAIR allocations, and 

where the cap existed, the new EGU was modeled at its cap. This allocation of the CAIR setaside for new EGUs provided a smaller pool of CAIR allowances for newly-permitted EGUs that 

had not begun operation. The remaining cap was proportionally allocated to the new EGUs 

based on their permitted emission rates. Only about 10 percent of the newly-permitted 

emissions could be covered by the remaining cap, but the allocation did not affect statewide NOX

emissions, since the overall CAIR cap for the state was modeled. 

As represented in the inventory, these newly-permitted units will operate at the modelingrestricted capacity, but in reality, they will likely operate at a higher capacity than modeled via 

trading, purchasing credits, or providing other offsets.

Pending permits (permit applications under TCEQ review, but not yet granted permits) were not 

included in this CAIR scenario for several reasons, including:

• The future operation of these units is more speculative.

• Adding more units under CAIR does not affect the total modeled EGU emissions, just where 

the emissions occur.

• Additional units would have been fit under the CAIR Phase I 9.5% set-aside, along with all 

the other post-2000 EGUs.

• The EGUs with approved permits have enough capacity to cover the 2012 future case power 

demand.

The temporal distributions of the newly-permitted EGU emissions are based on those of existing 

units of similar equipment type or SCCs. For each SCC included in the newly-permitted EGU 

list, an average temporal distribution was calculated, based on diurnal profiles of existing units 

within the state. For some units on the new EGU list, a corresponding SCC did not exist for 

existing units. In these cases, the default flat profile was assigned. An example of the profile 

used for a natural gas turbine is available in the March 2010 HGB Appendix B, Section 2.3.1.1.1.

2.3.1.1.3 Non-EGUs (NEGUs)

When the Acid Rain units are removed from the point source EI for hourly treatment, the 

remainder is OSD. The TCEQ refers to these remaining units as NEGUs. The basis for future 

growth for NEGUs in the Texas attainment areas was the 2006 OSD emissions, already an 

average OSD from STARS.

Emissions from NEGUs in the attainment areas of the state were projected to 2012 using a 

combination of projection factors. Projection factors derived from the Dallas Federal Reserve 

Bank’s Texas Industrial Production Index (TIPI) exist for growth from 2006 to 2018 and are 

based on an industry’s Standard Industrial Classification (SIC). For SICs not covered by TIPI, 

projection factors from EPA’s Economic Growth Analysis System version 5.0 (EGAS5) with a 

Texas-specific version of the Regional Economic Models, Inc (REMI) update were used. This 

version of EGAS with Texas-specific REMI is hereafter referred to as REMI-EGAS which, like 

the TIPI growth factors exists for growth from 2006 to 2018. No individual new permits were 

modeled as growth for NEGUs. The TCEQ modeled 2008 to 2012 by interpolating the 2006-

2018 data, using one third of the growth for the shorter time span.

While the use of either TIPI or REMI-EGAS could be argued, TIPI provided unexpectedly low 

emission rates for some point sources. The TCEQ chose to use the index that provided the most 
B-44

growth for each point source. Although there is not a TIPI factor available for all sources (only 

select SICs), there is a REMI-EGAS factor for each source (every SCC). For the SICs with 

missing TIPI factors, a value of 1.067, the average of the non-missing factors, was assigned. 

Examples of TIPI and REMI-EGAS growth factors are provided in the March 2010 HGB 

Appendix B, Section 2.3.1.1.2.

Projection factors were assigned individually to each NEGU path that does not have a recent 

rule applied to it based on its SIC-SCC combination. No factor was applied to a path that must 

comply with a recent rule, since the rule provides an emission limit on that path. The larger of 

either TIPI or REMI-EGAS was applied to all three modeled pollutants. A summary of the EGU 

and NEGU growth in the Texas attainment areas is provided as Table 15: Summary of Texas 

Attainment Area Growth Projections to 2012. In Table 15, a Growth Method of 1 indicates TIPI 

or REMI-EGAS was applied to points that do not have recent existing rule limitations; and a 

Growth Method of 2 indicates the addition of post-2006 point sources and CAIR applied to all 

points.

Table 15: Summary of Texas Attainment Area Growth Projections to 2012

EI

Future 

Case 

Baseline 

Data

Future 

Case 

Baseline 

# points

Future 

Case 

Baseline 

NOX (tpd)

Growth 

Method

2012 

Future 

Case 

#points

2012 

Projected 

NOX (tpd)

Baseline 

to 2012 

Growth

NEGUs 2008 

STARS 8939 436 1 8939 488 12%

EGUs 2008 

STARS/ARD 209 456 2 282 427 -6%

The TCEQ accounts for EGU growth by adding new facilities at locations where the facilities are 

permitted. The net reduction in EGU NOX emissions reflects the Best Available Control 

Technology (BACT) implemented in the New Source Review (NSR) permitting program of the 

TCEQ. CAIR Phase I limitations may further reduce NOX emissions from some EGUs. 

Any source that had an existing rule applied to it was capped at that rule level for the future, so 

only the remaining sources had growth factors applied to them. Controls are discussed in the 

next subsection.

2.3.1.1.4 Known Refinery Expansions in BPA

Three refineries in BPA have proposed increasing daily production levels, according to permit 

actions in the last few years. Motiva Enterprises, LLC (Motiva) is doubling the capacity at its 

Port Arthur refinery to 600,000 barrels per day, the Premcor Refining Group (Valero) is 

expanding its capacity to 420,000 from 300,000 barrels per day, and Total Petrochemicals USA 

Incorporated (Total) is increasing the capacity of its Port Arthur refinery by 50,000 barrels per 

day. Details and a summary of the emissions added via growth factor are available in the March 

2010 HGB Appendix B, Section 2.3.2.2.1. 

2.3.1.2 Texas Attainment Areas 2012 Existing Controls 

Existing on-the-books controls are incorporated into the 2012 future base. For the EGUs of the 

state, the control modeled was the EPA’s CAIR program. For the NEGUs in the attainment 

areas of the state, several existing controls were modeled, as described in following subsections.
B-45

2.3.1.2.1 EGUs

EPA has proposed the Clean Air Transport Rule (CATR), which is ultimately intended to replace 

CAIR. CATR was not modeled as it is not yet finalized. 

Under CAIR, 28 eastern states and the District of Columbia are required to comply with a cap on 

sulfur dioxide (SO2) and NOX EGU emissions. The definition of an EGU for the CAIR program is 

approximately the same definition as that for a Federal Clean Air Act Title IV Acid Rain unit, i.e., 

larger than 25 MW and more than one-third of its generation going to the public grid for sale. 

CAIR is a cap-and-trade program, with each of the CAIR-applicable states given calculated NOX

and SO2 budgets by the EPA. EPA determined by modeling that Texas significantly contributed 

to the nonattainment of the particulate matter of 2.5 microns and less (PM2.5) standard of two 

counties in Illinois. Texas was not included for eight-hour ozone contribution. Thus, Texas is 

not part of the CAIR ozone season (May through September) NOX budget, only the annual NOX

budget program. For more details on CAIR are available on EPA’s CAIR Texas webpage, 

http://www.epa.gov/cair/tx.html. Arkansas and Louisiana have ozone season NOX caps, and 

Oklahoma is not a CAIR state.

CAIR is implemented in two phases. For NOX, Phase I covers the years 2009-2014 and Phase II

covers the years 2015 and later; for SO2, Phase I covers the years 2010-2014 and Phase II covers

the years 2015 and later. Because 2012 is the DFW ozone attainment year, this SIP revision 

incorporates CAIR Phase I, which provides for a Texas state-wide NOX budget of 181,014 tons 

per year, or 496 tons per day. The CAIR allocations and past transactions for all relevant states 

can be found from the CAMD Allowances data query wizard website, 

http://camddataandmaps.epa.gov/gdm/index.cfm?fuseaction=allowances.wizard.

For implementing EPA’s CAIR program in Texas, the State Legislature mandated that the TCEQ 

allocate 90.5 percent of the CAIR budget to the EGUs that were operating on or before January 

1, 2001 (call these “existing” units in the “general pool”). Each existing EGU was apportioned its 

allowance of the budget based on fuel type and historical heat input. The remaining 9.5 percent

of the state CAIR budget cap was set aside for new (post-2000) EGUs, in the “new unit pool.” 

The newly-permitted EGUs obtain allowances from the new unit pool until these units have the 

appropriate actual emissions baseline used for the allocation of CAIR NOX allowances from the 

general pool.

For existing Acid Rain EGUs, the TCEQ distributed the assigned allowance cap for each unit in 

the general pool to the hourly average day 3Q2008 data file. More details regarding the

application of the CAIR program in Texas are available in the March 2010 HGB Appendix B, 

Section 2.3.1.2.1.

The TCEQ devised a method to apply the annual CAIR cap to ozone season emissions. Typically, 

NOX emissions are higher during ozone season, and since CAIR is an annual cap, a larger 

fraction of the cap will be expended during the summer. A straightforward seasonal adjustment, 

e.g., reallocating the cap based on historical ozone season-to-annual NOX emissions, resulted in

NOX caps that were unreasonably high in the DFW and Corpus Christi (CC) areas. This effect 

was likely caused by CAIR allocations that were based on outdated emissions data, and the high 

percentage of peaking units in these particular areas. As an alternative, the TCEQ modeled 

ozone season emissions using the annual cap instead of a seasonally adjusted value. This action 

was justified by comparing the results to the proposed CATR emission caps that would apply to 

ozone season for Texas. The statewide ozone season CATR and annual CAIR caps are nearly 

identical. Furthermore, the DFW and CC CATR allocations approximate 2008 emissions for the 

same point sources which are reasonable since 2012 is only four years removed from 2008.
B-46

For modeling purposes, the 9.5 percent set-aside cap for the new EGUs was applied to all post2000 point sources that began operation in the 2001-2008 time period (as evidenced by their 

Acid Rain emissions) and to post-2008 EGUs that have been permitted by TCEQ. Some of the 

new post-2000 units are currently operating and were given a CAIR allowance; the TCEQ 

modeled these points at their assigned cap. Some new units were not operating when caps were 

assigned, but were reporting emissions to CAMD. In those situations, the new points were 

modeled using their 2008 ARD emissions, and those emissions were taken from the CAIR (9.5

percent) new pool allocation.

A small amount of new unit pool CAIR allowance remained after the 2001-2008 new unit 

distribution. The TCEQ spread the remaining allowance among all the newly-permitted (post2008) EGU permits based on the modeling permitted rates but compressed to fit within the new 

unit pool. The modeling of this program is only an estimate and does not account for emissions 

trades that could occur. This modeling of the CAIR Phase I cap is even more complicated 

because of the MECT program in HGB, discussed in a later subsection. Attachment 1: Texas 

2010 CAIR NOX Allocations to this appendix contains a list of CAIR Phase I allocations by site

for 2010 sorted by ORIS. The table is a snapshot of CAIR allotments. Some of the facilities in 

the general pool may have shutdown or may be scheduled for shutdown, freeing their allotment 

for other facilities including new or proposed facilities. The table also shows that, at the time of 

this snapshot, not all of the new pool had been assigned to existing facilities, and this allocation 

is also available for other facilities.

A summary of the distribution of the general and new CAIR pools to areas of Texas is provided 

as Table 16: Distribution of NOX CAIR Allowances in Texas. 

Table 16: Distribution of NOX CAIR Allowances in Texas

Area Emissions 

Basis

Modeled Allowance 

for 2008 Units, tpd 

Modeled Allowance for 

Post-2008 Units, tpd 

DFW CAIR ARD 18.95

HGB CAIR OSD 0.61

HGB MECT ARD 36.09

Attainment CAIR OSD 0.11 7.70

Attainment CAIR ARD 423.45 9.17

The EGU portions of the HGB MECT program also count against the CAIR budget. MECT is 

more restrictive than CAIR, i.e., lower controlled allowable emission rate, ignoring trading, so 

the difference between CAIR and MECT was also modeled as a redistribution addition to 

statewide CAIR EGUs. Also, the CAIR units operating in 2008 were predominantly ARD units.

2.3.1.2.2 NEGUs

Several existing control programs are expecting further reductions between the baseline and 

2012 in the attainment areas of the state, including the East Texas Combustion Rule, specific 

Agreed Orders in East Texas, Chapter 117 NOX rules in BPA, and the Refinery Initiative.

2.3.1.2.2.1 East Texas Combustion Rule
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The East Texas Combustion rule was applied to rich-burn stationary gas-fired point source and 

area source engines in 33 identified attainment counties of East Texas. This Chapter 117 NOX

rule was shown to benefit DFW in the May 2007 DFW SIP revision. Almost three-quarters of 

the reductions came from point sources. Its full compliance date was March 2009; therefore, it 

qualifies as an existing rule with a future (post-baseline) compliance date. If a rule has a 

complete (all applicable sources) compliance date of 2006 or earlier, then compliance with the 

rule is assumed to have been incorporated in the baseline. This was modeled as a cap on the 

applicable sources at the 2009 rule emissions levels.

2.3.1.2.2.2 East Texas Agreed Orders

Federally-enforceable emissions reductions due to agreed orders and/or consent decrees were 

incorporated into the 2012 point source EI. These included the Eastman and ALCOA agreed 

orders as were modeled in previous SIP revisions. These appear to already be reporting zero 

emissions in the 2008 STARS EI, but were specifically shutdown in the modeling files, 

regardless.

2.3.1.2.2.3 BPA Chapter 117 Rules

The TCEQ applied Chapter 117 NOX emissions limits to BPA point sources over 25 tpy, as 

specified in the most recent BPA Attainment Demonstration with rules package.

2.3.1.2.2.4 Refinery Initiative

Since the late 1990s, petroleum refineries have been the focus of an EPA enforcement initiative. 

This initiative alleges that, in general, petroleum refineries violated and/or continue to violate 

one or more of the following regulatory Clean Air Act provisions, or parts thereof:

• Prevention of Significant Deterioration (PSD) requirements, 40 CFR 51-52;

• New Source Performance Standards (NSPS) requirements, 40 CFR 60;

• Leak Detection and Repair (LDAR) requirements, 40 CFR 60,61,63; or,

• National Emission Standards for Hazardous Air Pollutants (NESHAP) for Benzene Waste 

Operation, 40 CFR 61, Subpart FF.

In the interest of settling these allegations, without admitting to the alleged violations, many 

petroleum refiners have entered into consent decrees with EPA. Since March 2000, the EPA has 

entered into settlements with petroleum refiners that, collectively, represent nearly 80percent of 

U.S. petroleum refining capacity. According to the EPA, these settlements, covering 86 

refineries in 25 states, will result in a reduction of approximately 80,000 tons per year of 

nitrogen oxides (NOX) and 235,000 tons per year of sulfur dioxide (SO2) upon full 

implementation. See EPA’s webpage at 

http://www.epa.gov/compliance/resources/cases/civil/caa/oil/index.html for this and more 

details.

The TCEQ has not modeled any reductions for these consent decrees, because most of the 

agreements do not require NOX reductions, and most of them lack enforceable requirements of 

quantified reductions. The TCEQ can verify that several refineries (some in HGB and BPA) have 

modified permits to comply with their consent decrees, but permit reductions do not always 

result in actual reported emission reductions.

2.3.2

This section describes the specific growth and controls applied to the two ozone NAA, DFW and

HGB. The NAAs were modeled similarly, although HGB is more complex due to the number of 

Nonattainment Areas (NAAs) of Texas
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TCEQ programs that apply to it. The growth projections to 2012 and any existing controls that 

will affect the areas between the baseline and 2012 are described below. 

2.3.2.1 2012 Growth Projections

Growth projections were applied to the 2008 future base EI to obtain a 2012 grown EI. 

Different techniques were applied to the EGUs and the NEGUs. 

2.3.2.1.1 EGU Projections

As with the attainment areas of the state, the future base for EGUs in the NAAs of the state is the 

typical summer Acid Rain day having hourly emissions that are the average of all days in the 

third quarter of 2008 (3Q2008). Not all EGUs are Acid Rain units. The non-Acid Rain EGUs 

were modeled at their 2008 OSD emissions, as if they were NEGUs.

The complete set of 2012 EGUs consists of the 3Q2008 Acid Rain EGUs, the 2008 non-Acid 

Rain EGUs, and post-2008 EGUs that have approved TCEQ permits. As with previous SIP 

revisions, the TCEQ assumes that the EGU growth in the state comes from the TCEQ newlypermitted EGUs. This is similar to an assumption that the Integrated Planning Model (IPM) 

would make, which the EPA has used in all of its recent regional modeling studies, e.g., CAIR. 

The growth is spatially allocated based on permit applications.

2.3.2.1.1.1 Newly-Permitted EGUs in Nonattainment Areas (NAAs)

Table 14 lists all of the newly-permitted EGUs in each area of the state. There are no new 

planned units in DFW and 13 newly-permitted units in HGB. CAIR limitations are superseded 

by more stringent nonattainment NOX rules (30 TAC Chapter 117), although all EGU emissions 

must fit under the CAIR cap and absorb a share of the CAIR cap.

In HGB, adding newly-permitted EGUs is more complex, since all EGUs (and almost all 

combustion sources) must comply with the HGB Chapter 117 MECT program for NOX. For 

modeling purposes, new MECT sources are added under the cap and the cap is reallocated. In 

reality, the MECT cap is not reallocated for every new source, but as some sources shut down or 

reduce emissions; their part of the MECT cap is made available for use. There is no easy way to 

predict or model how that occurs. Instead, the TCEQ has assumed it is more important to place 

the new sources at the correct location with approximately the correct emissions, rather than 

not include them in the model at all. To maintain the integrity of the cap and model the MECT 

cap, the TCEQ reallocated the cap slightly to make room for the new sources.

The newly-permitted post-2008 EGUs in HGB are all MECT sources, as well as CAIR sources 

(the EGU must meet all applicable rules), and emissions from these points are reconciled with 

the MECT. MECT is a control program and will be addressed in more detail in the controls 

subsection, but it constrains the growth in HGB and is thus relevant here. The modeled HGB 

NOX emissions of Table 16 are within both the MECT and CAIR caps.

2.3.2.1.2 NEGU Projections

The basis for future growth for NEGUs in the Texas NAAs was the 2008 OSD emissions. No 

individual new permits were modeled as growth for NEGUs, except in BPA. Emissions from 

NEGUs in the NAAs of the state were projected to 2012 using the lesser of the TIPI-REMI-EGAS 

factors or the emission credits in the bank, described in the following paragraphs, except for 

HGB NOX, which is subject to the MECT program.

NAAs cannot grow in major sources of emissions of ozone precursors, NOX and VOC, except by 

purchasing from the bank to obtain emissions offsets during New Source Review of permit 
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applications or by sitewide contemporaneous period reductions, or to meet other TCEQ rules. 

The TCEQ has assumed that the emissions in the TCEQ Emissions Banking and Trading (EBT) 

Registry (bank) are available to come back into the airshed in the future, but are limited by the 

projected growth of point sources within the NAA. In other words, sources will only purchase 

from the bank what they actually need, and that need is projected by TCEQ with TIPI-REMIEGAS. Conversely, sources in need of large emissions growth in the future (predicted by TIPIREMI-EGAS), can only purchase as much credit as exists in the bank. For this 2012 projection 

analysis only the former case is true, because there is the need to only project emissions from 

2008 to 2012 with TIPI-REMI-EGAS, and there are plenty of banked emissions, i.e., there 

existed a growth-limited projection for each NAA, rather than a bank-limited condition.

The procedure for potentially incorporating the banked emissions in the future case begins with 

extracting the banked emissions from the TCEQ’s EBT Emission Reduction Credit (ERC) and 

Discrete Emission Reduction Credit (DERC) Registries, which can be found on EBT’s Registry 

webpage: http://www5.tceq.state.tx.us/airperm/index.cfm?fuseaction=registry.registry.

ERC and DERC totals for each of the NAAs, as of July 1, 2010 were extracted, tabulated, and 

summarized. According to 30 TAC §101.378, DERCs generated from shutdown strategies prior 

to September 30, 2002 are no longer available after September 8, 2010. These retiring DERCs 

were removed from the HGB modelable total for 2012. Table 17: Banked Emissions as of July 

2010 summarizes these results. Modelable emissions in Table 17 refers to the maximum 

amount of emissions that could be added as growth to the area from banked emissions, with the 

exception of HGB as noted below.

Table 17: Banked Emissions as of July 2010

NAA

NOX

ERCs

 (tpy)

VOC

ERCs

(tpy)

NOX

DERCs 

(tons)

VOC 

DERCs 

(tons)

CO 

DERCs

(tons)

Total 

Modelable NOX

Bank 

(tpd)

Total 

Modelable 

VOC 

Bank 

(tpd)

Total 

Modelable 

CO 

Bank 

(tpd)

HGB Registry 37.9 66.2 42323.4 1060.0 1488.4

HGB Model 33.0 57.6 1000.0 954.0 1339.6 2.8 2.8 3.7

BPA Registry 1078.1 79.3 2759.4 0 2591.8

BPA Model 980.1 72.1 2483.5 0.0 2332.6 9.5 0.2 6.4

DFW Registry 386.4 316.6 9624.0 5.0 0

DFW Model 336.0 275.3 8661.6 4.5 0.0 6.8 0.8 0.0

Chapter 101 of 30 TAC requires that an ERC must be surplus to any federal, state or local rule. 

Also, the Chapter 101 MECT program DERC-use restrictions for HGB were incorporated in the 

NOX total. 30 TAC Chapter 101.379, DFW DERC Flow Control Rule, did not offer a limitation on 

the growth for this SIP revision, for the reasons stated below, and because there were only four 

years of growth to apply, limiting the amount of banked emissions that are predicted to be 

purchased.

The flow control calculation for 2012 would limit the DFW DERC usage to 5.93 tpd, based on 

the equation in 30 TAC §101.379(c)(2)(A) using MOBILE6.2 fleet turnover. This flow control 

calculation may be updated in the future to use MOVES2010a fleet turnover. Adding the 

modelable DFW NOX ERCs to the 5.93 tpd of DFW NOX DERCs brings the total modelable NOX
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bank for DFW to 6.8 tpd, as shown in Table 17. However, that maximum bank was not included 

in the final model run as the TIPI-REMI-EGAS projection limited the DFW growth to only 0.2

tpd (Table 18: Texas NEGU “No-Rules” Growth Summary). A 2012 model sensitivity was 

completed using the ERC registry and the flow control calculated DERCs of 5.93 tpd (the total of 

6.8 tpd, as shown in Table 17), and the maximum future design value was unchanged. 

Additional details on the modeling sensitivity of the ERC registry and the DERC flow control 

limit are in Attachment 3 of this Appendix. These changes indicate the use of the ERC registry 

and the DERC flow control limit would not impact the determination of attainment in 2012.

As a worst case, the totals indicated in Table 17 incorporate the originally-designated eight-hour 

ozone offset ratios for each of the NAAs (and even BPA, for which a bank is maintained even 

though it is in attainment now), where an offset ratio of 1.15:1 for moderate areas indicates that 

the purchaser of ERCs must buy 11.5 ton per year of credits for each 10 tons per year of increase 

proposed. Additionally, the modelable bank took into account the requirement of Chapter 101 

to retire 10 percent of the DERCs, as an environmental contribution, upon DERC usage

2.3.2.1.2.1 HGB NOX Mass Emissions Cap and Trade (MECT)

The HGB MECT program limits the amount of NOX from all applicable sources with a cap. The 

application of this program and its limits are discussed in the March 2010 HGB Appendix B, 

Section 2.3.2.1.1.

Table 18 shows the growth projected in each of the NAAs from each of the indices. Again, the 

growth was only applied to the sources that were not already limited by existing TCEQ SIP rules. 

Table 18: Texas NEGU “No-Rules” Growth Summary

Area Projection 

Index

2008 STARS 

NOX, tpd

NOX

Growth, 

tpd

2012 NOX, 

tpd

2008 

STARS 

VOC, tpd

VOC 

Growth, 

tpd

2012 

VOC, tpd

DFW from EGAS 0.94 0.13 1.07 30.71 0.59 31.30

DFW from TIPI 0.63 0.08 0.71 7.11 0.21 7.32

HGB from EGAS 13.5 1.3 14.8 78.5 7.3 85.8

HGB from TIPI 12.0 -1.2 10.8 55.3 8.6 63.9

Attainment from EGAS 365.3 41.2 406.5 207.6 18.4 226.0

Attainment from TIPI 97.3 15.7 113.0 87.8 12.1 99.9

The bank and the TIPI-REMI-EGAS were compared on a path-by-path basis, automated with 

SAS programming. The bank growth in each NAA was the bank divided by the total emissions 

in the NAA. A path’s share of the bank was based on its fractional emissions of the total, and 

was added to that path. Only the paths not already limited by rules were allowed to grow via the 

bank or TIPI-REMI-EGAS.

2.3.2.1.2.2 HGB HRVOC Emissions Cap and Trade (HECT) 

The other cap-and-trade program within HGB that applies to NEGUs is the HRVOC Emissions 

Cap and Trade (HECT) program. The compounds specifically regulated by HECT are the four 

HRVOC species, ethylene, propylene, 1,3-butadiene, and butenes, where butenes includes all 

isomers of butene. The background and speciation procedure for the HRVOC and the HECT cap 

have been provided in a presentation that was given at the 17th Annual International EI 

Conference, in Portland, Oregon, in 2008. The presentation can be found at the conference web
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page, http://www.epa.gov/ttn/chief/conference/ei17/session6/thomas_pres.pdf, and the 

detailed paper from the conference proceedings can be found at

http://www.epa.gov/ttn/chief/conference/ei17/session6/thomas.pdf

HECT-applicable units are flares, process vent stacks, or cooling towers in Harris County that 

have the potential to emit more than ten tpy HRVOC. Smaller sites in Harris County may opt-in 

to the HECT program. These are all primary sources, not secondary, of HRVOC emissions. 

HECT allowances were allocated to applicable sites in proportion to the site's level of activity, 

determined from each site's selection of a twelve-consecutive-month baseline from 2000 

through 2004. HECT sites were given the greater of 5.0 tons of HECT allowances or the 

allocation from the site, determined from using the equation listed in 30 TAC §101.394(a)(1). 

.

With the March 2010 HGB SIP Revision, HECT was reduced to 75 percent of its overall cap and 

reallocated. The TCEQ modeled the most current version of the HECT allocations. Since this is 

a trading program, HECT-applicable sites may bank or trade HRVOC between other HECT sites, 

as long as the account is reconciled at or below its allowance level before the end of the HECT 

reconciliation period each year. Additional details of this Harris County control program are in 

the March 2010 HGB Appendix B, Sections 2.3 and 2.4.

2.3.2.1.2.3 2012 Tank Landing Losses (TLL)

The emissions used for the HGB TLL for the 2012 future base are the same as the baseline.

It is likely that by the compliance date of January 1, 2009, further VOC reductions will be 

actualized from the Chapter 115 rules, which limit convenience floating roof tank landings, since

reported emissions decreased between 2004 and 2007. However, it is difficult to quantify the 

future emissions reductions expected. The TCEQ decided to take no credit for any future 

convenience landing reductions.

2.3.2.1.2.4 2012 Emission Inventory Reconciliation in HGB (aka, HRVOC Reconciliation, 

Extra Olefins)

2006 was the first full year for reporting of monitored HRVOC, as required by 30 TAC Chapter 

115. Additionally, 2006 was the year of the HECT survey. Table 7 shows a total of 19.3 tpd of 

HRVOC were added to grid cells in HGB as the reconciled HRVOC. Additional details of the 

HGB 2018 Reconciled HRVOC emissions are in the March 2010 HGB Appendix B, Section 

2.3.2.1.2.

2.3.2.1.3 DFW Existing (2012 Future Base) Controls 

This section describes several existing NOX rules for DFW, most notably Chapter 117 Major 

Source NOX rules, which were previously implemented via SIP rules. Additionally, there is a

Chapter 117 Cement Kiln cap to apply for DFW discussed below. The most recent DFW 

attainment demonstration SIP revision was adopted by the Commission in May 2007. These 

control programs are on-the-books rules with final compliance dates after the 2006 baseline 

year and prior to 2012.

2.3.2.1.3.1 DFW 5% IOP Rules

The DFW 5% Increment of Progress (IOP) SIP revision identified required emissions reductions 

in the added five counties for the DFW eight-hour ozone NAA. These included VOC reductions 

from the DFW Surface Coating rule. There were also NOX reductions from ICI (Industrial, 

Commercial, Institutional) reciprocating gas-fired engines in the nine-county area, but the NOX

rules were generally made more strict by the Major Source Rule (see next paragraph). Thus,

only the VOC controls were specifically modeled in this control packet, as was done for the May 
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2007 DFW SIP revision. These rules were adopted by the Commission in April 2005 and were 

assumed after the 2006 reported EI.

2.3.2.1.3.2 DFW 2009 Ch. 117 Major Source Rule

The DFW major source rule controls ICI (Industrial, Commercial, Institutional) NEGU point 

sources. It approximates the Chapter 117 NOX Emission Standards for Attainment 

Demonstration (ESADs) that are in place in HGB, and adds some ESADs for source categories 

that did not exist or were otherwise not regulated in HGB. The compliance dates for these were 

March 2009. The paths affected by these rules are those modeled for the May 2007 DFW SIP 

revision.

2.3.2.1.3.3 DFW 2009 Midlothian Cement Kiln Cap

The level of controls applied to the Midlothian, Ellis County, cement kilns is that which resulted 

from the May 2007 DFW SIP revision. Site-wide (by account) alternative NOX caps were 

modeled based on this rule, as modified by baseline changes reported by the sites. These 

updated ozone season (March 1 through October 1) caps, totaling 17.6 tpd for the ten kilns at the 

three sites, have been modeled as shown in Table 19: Ellis County Cement Kiln NOX Caps, 

below. TXI has applied for a permit alteration to cease operation of its four wet kilns (future 

emissions of 0.00 tpd) in exchange for increasing clinker production in its newer dry kiln 

process.

Table 19: Ellis County Cement Kiln NOX Caps

Sitename FIN EPN

NOX

Emissions 

(tpd)

Ash Grove Midlothian Plant 2-1 2 1.43

Ash Grove Midlothian Plant 2-2 6 1.51

Ash Grove Midlothian Plant 2-3 12 1.45

Holcim Midlothian Plant 62* 62* 2.10

Holcim Midlothian Plant 07* 07* 3.20

TXI Operations Midlothian Plant E-2-2 E2-2 0.00

TXI Operations Midlothian Plant E-2-4 E2-4 0.00

TXI Operations Midlothian Plant E-2-6 E2-6 0.00

TXI Operations Midlothian Plant E-2-8 E2-8 0.00

TXI Operations Midlothian Plant E2-22 E2-22 7.90

2.3.2.1.3.4 DFW 2012 EI Summary

The future case EI is composed of two datasets, hourly average 3Q2008 for the ARD sources and 

2008 OSD for the remainder of the point sources. The 2012 future base is built upon these 

datasets by incorporating the changes expected due to growth, emission caps, and on-the-books 

controls. Table 20: Detailed NOX 2012 Emissions Summary by Region provides a 2012 

emissions summary. 
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Table 20: Detailed NOX 2012 Emissions Summary by Region

Region Projection Affected Sources

2008 

STARS 

NOX, 

tpd

2008 

ARD 

NOX, 

tpd

2012 

NOX

Projection, 

tpd

DFW CAIR Points in general pool 2.94 15.86

DFW CAIR Points in new pool 3.98 3.09

DFW Controls DFW major NOX 18.38 12.67

DFW Controls Midlothian Kilns 18.37 17.60

DFW Growth EGAS 0.94 1.07

DFW Growth TIPI 0.63 0.71

HGB CAIR Points in new pool 0.00 0.14

HGB CAIR MECT points in new pool 0.00 0.46

HGB MECT OSD point sources 55.68 77.09

HGB MECT Growth under the cap 0.00 9.08

HGB MECT ARD point sources 0.20 0.10

HGB MECT MECT in general CAIR pool 24.17 27.49

HGB MECT MECT in new CAIR pool 7.62 8.50

HGB MECT exempt EGAS 13.47 18.92

HGB MECT exempt TIPI 12.02 13.81

Rest of TX CAIR OSDs in general pool 0.00 0.32

Rest of TX CAIR OSDs in new pool 0.00 7.49

Rest of TX CAIR ARDs in general pool 418.50 405.22

Rest of TX CAIR ARDs in new pool 31.07 27.40

Rest of TX Controls BPA NOX controls 13.84 19.42

Rest of TX Controls DFW major NOX 2.14 1.62

Rest of TX Controls ETX combustion 3.73 0.89

Rest of TX Controls ETX agreed orders 0.00 0.00

Rest of TX Growth EGAS 365.34 406.50

Rest of TX Growth TIPI 97.27 113.01

Rest of TX Growth Refinery expansion 5.35 5.39

2.3.3

Regional emissions include states outside of Texas within the modeling domain, Gulf of Mexico

offshore, and the parts of Mexico and Canada within the modeling domain. The same procedure 

was used to model 2012 adjacent states as the remainder of the states beyond Texas. Any 

differences will be specifically noted.

Regional (Outside of Texas) Point Sources

2.3.3.1 States Outside of Texas

2.3.3.1.1 EGUs

The TCEQ distinguishes between EGUs and Acid Rain units. Not all EGUs (SIC 4911 and 4939) 

are Acid Rain units, e.g., true cogeneration units are not Acid Rain units, but large cogeneration 

units that supply more than one-third of their electricity to the public electrical grid are Acid 

Rain units. Non-Acid Rain EGUs are treated as NEGUs. This is the same definition that the 

EPA applies to EGUs for CAIR purposes, i.e., an EGU, as defined by CAIR, is an Acid Rain EGU.
B-54

The TCEQ built future case 2012 emission records for Acid Rain EGUs using the 2008 third 

quarter (3Q2008) hourly data downloaded from the EPA’s CAMD website. A single 2008 

typical summer acid rain day having average hourly emissions for each Acid Rain EGU was built 

to represent the future base for the EGUs. Existing controls were applied to generate the future 

case 2012. 

The TCEQ applied existing controls to the 3Q2008 emissions dataset to complete the projection 

to 2012. The controls assumed are the CAIR Phase I NOX budgets for each state as defined by 

EPA’s Notice of Data Availability (NODA) allocations spreadsheet, obtained from EPA’s website

http://www.epa.gov/airmarkt/progsregs/cair/noda.html.

If a state had an ozone season budget, it was the assumed budget; otherwise, the annual budget 

was converted to a ton per day limit. States not having a CAIR limitation were modeled at their 

2008 emissions.

Table 21: Modeled CAIR Phase I NOX Allocations for States in the Modeling Domain gives the 

CAIR cap emissions for each state in the modeling domain. An empty cell indicates no CAIR cap 

for that state.

Table 21: Modeled CAIR Phase I NOX Allocations for States in the Modeling 

Domain

State Ozone Season 

CAIR Cap, tpd 

Annual CAIR Cap, 

tpd

Modeled CAIR Cap, 

tpd

2008 ARD 

Emissions, tpd

AL 199.82 179.64 199.82 229.56

AR 71.50 71.50 113.51

CT 15.89 15.89 8.33

DC 0.69 0.38 0.69 0.41

DE 13.82 10.84 13.82 20.34

FL 297.49 258.83 297.49 466.96

GA 172.62 172.62 211.62

IA 88.56 85.09 88.56 129.07

IL 190.63 198.41 190.63 222.94

IN 285.32 283.53 285.32 381.48

KS 153.56

KY 223.81 216.56 223.81 252.48

LA 106.08 92.43 106.08 149.40

MA 46.88 46.88 18.37

MD 79.69 72.16 79.69 61.73

MD 79.69 72.16 79.69 61.73

ME 0.43

MI 179.88 169.97 179.88 240.19

MN 81.84 166.29

MO 165.65 155.83 165.65 237.08

MS 54.10 46.35 54.10 129.06

NC 176.29 161.85 176.29 142.80
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State Ozone Season 

CAIR Cap, tpd 

Annual CAIR Cap, 

tpd

Modeled CAIR Cap, 

tpd

2008 ARD 

Emissions, tpd

ND 185.19

NE 117.90

NH 12.84

NJ 41.31 32.98 41.31 29.76

NY 128.10 118.73 128.10 86.77

OH 283.54 282.83 283.54 341.13

OK 247.44

PA 261.84 257.80 261.84 329.69

RI 0.36

SC 94.69 85.01 94.69 88.91

SD 35.26

TN 141.83 132.67 141.83 115.60

VA 99.31 93.89 99.31 84.25

VT 0.78

WI 111.69 106.08 111.69 132.52

WV 166.77 193.18 166.77 164.16

Table 22: Modeled 2012 Typical Day Acid Rain EGU Emissions for Regional States summarizes 

the Acid Rain EGU emissions data for point sources outside Texas. The Rest of U.S. column

totals are for all states in the modeling domain, excluding Texas, Arkansas, Louisiana and 

Oklahoma, although parts of some states may extend outside the modeling domain. Thus, 

CAMx inputs would be expected to be less than the totals in Table 22.

Table 22: Modeled 2012 Typical Day Acid Rain EGU Emissions for Regional States

Hour

AR 

NOX

tph

LA

NOX

tph

OK 

NOX

tph

Rest of 

U.S. NOX

tph

1 2.89 3.96 8.68 146.43

2 2.80 3.85 8.46 141.44

3 2.68 3.79 8.30 138.72

4 2.64 3.80 8.24 139.35

5 2.71 3.86 8.43 145.45

6 2.73 3.89 8.57 153.51

7 2.83 3.93 8.86 160.44

8 2.92 4.03 9.02 168.63

9 3.00 4.14 9.46 176.29

10 3.03 4.28 10.26 183.88

11 3.06 4.44 11.06 188.96

12 3.12 4.66 11.67 193.71
B-56

Hour

AR 

NOX

tph

LA

NOX

tph

OK 

NOX

tph

Rest of 

U.S. NOX

tph

13 3.19 4.96 12.18 197.60

14 3.20 5.19 12.51 200.23

15 3.22 5.32 12.64 201.14

16 3.21 5.34 12.76 201.12

17 3.18 5.20 12.55 199.30

18 3.13 4.96 12.14 194.78

19 3.13 4.75 11.50 190.79

20 3.09 4.62 11.11 189.10

21 2.94 4.47 10.64 184.03

22 2.94 4.34 10.09 174.97

23 2.92 4.18 9.36 163.98

24 2.94 4.09 8.95 154.24

TOTALS 71.51 106.08 247.44 4188.06

#points 16 52 73 1,202

2.3.3.1.2 NEGUs

The 2012 NEGU emissions for states beyond Texas were interpolated from the 2018 

CenRAP/RPO file after the EGUs were removed. Growing 2006 emissions to 2012 would not 

have captured the controls that were built into the regional modeling files. Table 23: 2012 

Regional States NEGU Emissions represents the NEGU emissions for states beyond Texas, but 

within the modeling domain. CAMx inputs would be expected to be less than the totals 

tabulated.

Table 23: 2012 Regional States NEGU Emissions

State Number of 

NOX points

NOX

Emissions, 

tpy

Number of 

VOC points

VOC 

Emissions, 

tpy

Number of 

CO Points

CO 

Emissions, 

tpy

AL 1,805 89,549 3,192 55,554 1,817 204,191

AR 1,075 34,796 2,106 39,377 1,101 63,619

CN 854 8,914 1,203 4,897 832 7,549

DC 44 894 61 83 43 448

DE 386 4,833 1,009 3,589 383 9,263

FL 1,766 84,034 3,154 44,876 1,611 121,506

GA 1,749 62,045 2,509 40,394 1,651 174,871

IL 6,175 106,244 15,080 75,666 5,898 96,457

IN 3,154 115,841 7,674 71,503 3,059 446,859

IO 2,907 49,362 6,683 40,499 2,744 45,479

KS 2,698 89,809 4,391 33,438 2,610 103,991

KY 2,812 43,829 8,320 53,485 2,717 141,081
B-57

State Number of 

NOX points

NOX

Emissions, 

tpy

Number of 

VOC points

VOC 

Emissions, 

tpy

Number of 

CO Points

CO 

Emissions, 

tpy

LA 4,073 234,256 7,489 96,982 3,748 161,639

MA 5,551 26,916 8,596 10,474 4,502 19,188

ME 1,522 51,070 2,443 12,853 1,472 157,350

MI 3,439 135,140 8,935 45,784 2,866 97,045

MN 4,847 75,916 8,593 42,241 4,604 58,071

MO 4,152 54,660 8,384 41,942 3,878 161,984

MS 1,458 65,878 2,437 47,906 1,441 70,147

NC 2,619 58,759 4,992 73,350 2,630 65,713

ND 126 93,680 96 2,381 130 17,880

NE 911 20,515 1,172 9,133 852 8,225

NH 207 1,688 233 1,287 206 1,291

NJ 5,120 28,000 10,508 17,098 4,650 15,542

NY 2,092 57,427 2,644 7,805 2,074 86,454

OH 2,067 237,518 3,244 34,410 1,871 292,475

OK 2,379 88,660 5,475 43,666 2,385 76,014

PA 6,990 128,263 11,807 43,481 6,716 148,313

RI 139 2,452 259 2,269 140 2,830

SC 2,729 51,743 4,541 43,892 2,676 74,327

SD 79 15,857 88 3,203 67 6,076

TN 1,744 71,102 4,901 97,269 1,661 136,731

VA 2,248 75,957 3,898 51,628 2,106 80,414

VT 89 922 73 1,613 85 786

WI 4,373 80,270 9,666 41,226 4,097 47,110

WV 1,167 51,046 2,728 16,631 1,206 107,463

Table 24: 2012 Regional States Emissions Summary provides an overall summary of the 2012 

emissions for all the states within the modeling domain, outside of Texas. As parts of some 

states may extend outside the modeling domain, CAMx inputs would be expected to be less than 

the totals tabulated.

Table 24: 2012 Regional States Emissions Summary

Model Year Source 

Category

NOX

Emissions, 

tpd

VOC 

Emissions, 

tpd

CO 

Emissions, 

tpd

2006 Baseline EGU 6525 47 1720

2012 Future Case EGU 4613 41 1364

2006 Baseline NEGU 7645 3331 8213

2012 Future Case NEGU 6569 3430 9064
B-58

2.3.4

The GWEI 2005 report mentioned declines in the number of platforms between 2000 and 2005, 

and platforms have been tending to be located farther offshore in deeper water, so the impact to 

onshore areas may be decreasing. However, MMS has not provided projections for the offshore 

EI. For lack of projections data, the 2012 EIs for the Gulf of Mexico offshore area, Mexico, and 

Canada were the same as those used in the 2006 baseline and the base case, as described in 

previous sections.

Offshore, Mexico, and Canada

2.3.5

The point source emission files that were processed with EPS3 for CAMx are presented in 

Summary of Future Case Point Source Data Files

Table 

25: AFS Files for the 2012 Future Case Episode. The regional AFS file for the GWEI contains 

monthly emissions for June only and the regional AFS file for Canadian emissions contains 

annual emissions. The version number on each dataset indicates a change from the previous 

version (e.g., “v8”). The FTP download site for these files is

ftp://amdaftp.tceq.texas.gov/pub/DFW8H2/ei/2012/point.

Table 25: AFS Files for the 2012 Future Case Episode

Area AFS Point Source Emissions Dataset Hourly Daily Special 

Texas afs.ard_MECT_with_season_adjustment_v5 X

Texas afs.ard_2008_not_in_MECT_or_HECT_v3 X 1

Texas afs.ard_CAIR_DFW_with_season_adjustment_v5 X

Texas afs.osd_MECT_for_DFW_NOx_pts_v3 X

Texas afs.osd_MECT_exempt_growth_to_2012_DFW.v1 X

Texas afs.osd_growth_under_MECT_v3 X

Texas afs.2012_HECT_HarrisCo_2008_basis_all_pts_v1 X

Texas afs.osd_CAIR_DFW_with_pathway_allowances_v4 X

Texas afs.osd_2008_DFW_controls_v2 X

Texas afs.osd_no_rules_growth_to_2012_w_TLL_adjustment.v2 X

Texas afs.landing_losses_3Q06_aver_day_episode_vDFW1 X

Texas afs.aggVOC_extra_alkenes_for_2006_vDFW1 X

Regional afs.ard_USAmTX_generic_CAIR_based_on_pt_caps.v1 X

Regional afs.osd_2012_USA_NEGUS_interpolated_from_CENRAP X

Regional afs.gwei2005.May_Oct_edit.3pol.lcp Monthly

Regional afs.Mexico_from_updated_1999_NEI.lcp_3pols_v1 X

Regional afs.CAIRCanada.2001.v1a.latlong.lcp Annual

Table 26: 2012 Future Case Point Source Emissions Summary summarizes the future case 

emissions. These tabulated emissions are AFS totals input to EPS3. CAMx input values may 

differ. The U.S. minus Texas column includes some points outside the modeling domain. The 

TX minus DFW column includes some points in Texas outside the modeling domain.
B-59

Table 26: 2012 Future Case Point Source Emissions Summary

Emission Source

DFW 

NOX

(tpd)

DFW 

VOC 

(tpd)

TX minus 

DFW 

NOX (tpd)

TX minus 

DFW 

VOC (tpd) 

U.S. minus 

TX NOX

(tpd)

U.S. minus 

TX VOC 

(tpd)

NEGUs (OSD) 32.0 38.6 674.2 526.4 6569.4 3429.8

EGUs (ARD) 18.9 0.8 468.8 15.7 4613.1 41.1

Tank Landing Losses 6.5

HRVOC 

Reconciliation 19.3
B-60

3 ON-ROAD MOBILE SOURCE MODELING EMISSIONS DEVELOPMENT

3.1 On-Road Mobile Source Emissions Inventories for Nine-County DFW

The purpose of this section is to provide a brief overview of the nine-county DFW area on-road 

mobile source emissions inventory files that were input into the photochemical model for the 

2006 base case, the 2006 baseline case, and the 2012 future case. These inventory data sets were 

developed under contract by the North Central Texas Council of Governments (NCTCOG) based 

on travel demand model (TDM) output for the DFW area. For each of the nine DFW counties, 

NCTCOG combined MOVES2010a emissions rate output with vehicle miles traveled (VMT) 

estimates from the local TDM. The net result is referred to as a link-based inventory because 

both hourly VMT and emissions estimates are developed for each roadway segment or link in 

the network. For each year, summer season on-road emission inventories were developed for 

the five day types of weekday (i.e., Tuesday-Thursday average), Friday, Saturday, Sunday, and 

Monday. Since these days types are based on a summer season, development of separate 

baseline OSD emissions was not needed. For the on-road category, base case and baseline 

emissions are the same.

Table 27: VMT, NOX, VOC, and CO Summary for 2006 DFW On-Road Inventory and Table 28: 

VMT, NOX, VOC, and CO Summary for 2012 DFW On-Road Inventory provide summaries of the 

total VMT, NOX, VOC, and CO emissions for the entire nine-county DFW area for each day type 

for the 2006 case and 2012 future case, respectively. As shown, Fridays have the highest total 

VMT of the week, while Saturdays and Sundays have the lowest total daily VMT. While overall 

VMT increases with future growth, total emissions decrease from 2006 to 2012 as a result of 

more stringent emissions standards for newer vehicles entering the fleet, combined with the 

simultaneous attrition of older, higher-emitting vehicles. Consistent with current federal and 

state rules, the on-road inventories from NCTCOG include the benefits of:

• reformulated gasoline (RFG) in Collin, Dallas, Denton, and Tarrant Counties;

• low Reid vapor pressure (RVP) gasoline in Ellis, Johnson, Kaufman, Parker, and Rockwall 

Counties;

• the inspection and maintenance (I/M) Program in all nine counties; and

• Texas low emission diesel (TxLED) fuel for all nine counties.

Table 27: VMT, NOX, VOC, and CO Summary for 2006 DFW On-Road Inventory

Day

Type

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Weekday 151,358,205 259.11 111.02 1,209.12

Friday 167,642,908 263.85 114.42 1,304.22

Saturday 136,773,126 189.78 103.22 1,130.87

Sunday 112,618,220 169.77 96.89 995.36

Monday 148,101,765 252.59 109.15 1,187.58

Table 28: VMT, NOX, VOC, and CO Summary for 2012 DFW On-Road Inventory

Day

Type

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Weekday 186,388,044 181.40 80.48 955.75

Friday 200,764,362 181.90 81.75 1,010.32

Saturday 163,286,714 136.50 74.77 879.39
B-61

Day

Type

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Sunday 139,048,881 125.47 71.55 789.76

Monday 180,038,229 175.34 78.97 930.51

Even though all of the day type on-road inventory data sets were used for photochemical model 

input, only the summer weekday emissions will be detailed here. For the 2006 base case and 

2012 future case, Table 29: Summary of 2006 DFW Summer Weekday On-Road Inventory by 

County and Table 30: Summary of 2012 DFW Summer Weekday On-Road Inventory by County

present respective summaries of the VMT, NOX, VOC, and CO emissions for each of the nine 

counties in the DFW area.

Table 29: Summary of 2006 DFW Summer Weekday On-Road Inventory by County

DFW Area

County

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 15,622,536 23.94 10.69 108.65

Dallas 62,826,353 104.83 46.41 510.76

Denton 13,205,166 22.50 9.33 93.29

Ellis 5,503,696 12.43 3.68 46.63

Johnson 4,448,585 9.35 3.72 44.95

Kaufman 4,460,300 9.48 2.60 36.24

Parker 3,723,312 8.81 2.71 34.02

Rockwall 1,891,799 3.71 1.32 15.59

Tarrant 39,676,458 64.05 30.58 318.99

Total 151,358,205 259.11 111.02 1,209.12

Table 30: Summary of 2012 DFW Summer Weekday On-Road Inventory by County

DFW Area

County

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 21,232,596 17.56 8.36 95.47

Dallas 72,976,845 70.15 32.00 390.93

Denton 17,746,832 16.18 7.13 80.02

Ellis 7,580,609 9.59 2.79 34.08

Johnson 5,829,182 7.00 2.67 30.42

Kaufman 6,170,056 7.15 1.98 26.52

Parker 5,027,970 6.47 1.98 23.55

Rockwall 2,422,684 2.59 1.02 11.03

Tarrant 47,401,269 44.71 22.55 263.72

Total 186,388,044 181.40 80.48 955.75

Table 31: Summary of 2006 DFW Summer Weekday On-Road Inventory by Vehicle Type and 

Table 32: Summary of 2012 DFW Summer Weekday On-Road Inventory by Vehicle Type
B-62

present respective summaries for 2006 and 2012 of the VMT, NOX, VOC, and CO emissions for 

each of the gasoline and diesel fuel source use type (SUT) combinations from the MOVES2010a 

model.

Table 31: Summary of 2006 DFW Summer Weekday On-Road Inventory by Vehicle 

Type

Fuel and Source Use Vehicle Miles NOX VOC CO

Type Combination Traveled (tpd) (tpd) (tpd)

Gasoline - Motorcycle 113,799 0.09 1.62 2.24

Gasoline - Passenger Car 113,307,791 92.59 65.36 697.43

Gasoline - Passenger Truck 22,109,764 38.66 26.34 330.99

Gasoline - Light Commercial Truck 5,822,205 11.05 7.47 95.40

Gasoline - Transit Bus 382 0.00 0.00 0.03

Gasoline - School Bus 11,945 0.07 0.05 0.78

Gasoline - Refuse Truck 3,746 0.02 0.01 0.18

Gasoline - Single Unit Short-Haul Truck 969,735 3.76 1.36 33.61

Gasoline - Single Unit Long-Haul Truck 133,521 0.50 0.18 4.12

Gasoline - Motor Home 119,033 0.51 0.18 4.17

Gasoline - Combination Short-Haul Truck 794 0.01 0.00 0.07

Diesel - Passenger Car 377,430 0.70 0.05 0.21

Diesel - Passenger Truck 74,595 0.40 0.06 0.35

Diesel - Light Commercial Truck 1,128,486 6.06 0.84 5.17

Diesel - Intercity Bus 139,191 2.89 0.12 0.86

Diesel - Transit Bus 38,787 0.65 0.04 0.24

Diesel - School Bus 144,680 1.46 0.12 0.57

Diesel - Refuse Truck 89,914 0.99 0.06 0.32

Diesel - Single Unit Short-Haul Truck 2,145,902 14.57 1.55 6.48

Diesel - Single Unit Long-Haul Truck 300,394 1.98 0.22 0.87

Diesel - Motor Home 69,313 0.53 0.06 0.19

Diesel - Combination Short-Haul Truck 1,755,263 28.79 1.31 8.39

Diesel - Combination Long-Haul Truck 2,501,535 52.83 4.04 16.44

Total 151,358,205 259.11 111.02 1,209.12

Table 32: Summary of 2012 DFW Summer Weekday On-Road Inventory by Vehicle 

Type

Fuel and Source Use Vehicle Miles NOX VOC CO

Type Combination Traveled (tpd) (tpd) (tpd)

Gasoline - Motorcycle 137,736 0.09 2.13 1.70

Gasoline - Passenger Car 137,141,621 58.79 44.63 536.70

Gasoline - Passenger Truck 26,162,921 29.16 18.04 241.36

Gasoline - Light Commercial Truck 9,965,919 12.66 7.54 102.76

Gasoline - Transit Bus 441 0.00 0.00 0.01
B-63

Fuel and Source Use Vehicle Miles NOX VOC CO

Type Combination Traveled (tpd) (tpd) (tpd)

Gasoline - School Bus 13,800 0.07 0.05 0.79

Gasoline - Refuse Truck 5,107 0.02 0.01 0.14

Gasoline - Single Unit Short-Haul Truck 1,321,812 4.33 1.33 32.15

Gasoline - Single Unit Long-Haul Truck 181,998 0.57 0.17 3.88

Gasoline - Motor Home 162,250 0.57 0.16 3.50

Gasoline - Combination Short-Haul Truck 913 0.01 0.00 0.05

Diesel - Passenger Car 456,821 0.16 0.02 0.54

Diesel - Passenger Truck 88,270 0.36 0.05 0.31

Diesel - Light Commercial Truck 1,931,639 6.90 0.85 5.63

Diesel - Intercity Bus 160,803 2.16 0.10 0.72

Diesel - Transit Bus 44,809 0.46 0.03 0.21

Diesel - School Bus 167,144 0.98 0.09 0.47

Diesel - Refuse Truck 122,559 0.57 0.03 0.21

Diesel - Single Unit Short-Haul Truck 2,925,006 9.16 0.90 5.34

Diesel - Single Unit Long-Haul Truck 409,457 1.30 0.14 0.72

Diesel - Motor Home 94,478 0.40 0.05 0.17

Diesel - Combination Short-Haul Truck 2,017,408 14.94 0.67 4.69

Diesel - Combination Long-Haul Truck 2,875,135 37.74 3.48 13.67

Total 186,388,044 181.40 80.48 955.75

The MOVES2010a run specification files used to develop these inventories, along with detailed 

reports and tab-delimited summary output data, can be found on the following FTP sites for 

2006 and 2012, respectively:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/mvs/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/mvs/2012/

3.2 On-Road Mobile Source Emissions Processing

The on-road emissions inventory data provided by NCTCOG were prepared for input into the 

photochemical model using EPS3. When input into EPS3, the inventory data are in a readable 

text-based format. However, once within EPS3, the emissions data are maintained in a binary 

format. Table 33: EPS3 Modules Used to Process Nine-County DFW On-Road Emissions Data

summarizes the EPS3 modules that were used to process the nine-county DFW on-road 

inventories.

Table 33: EPS3 Modules Used to Process Nine-County DFW On-Road Emissions 

Data

EPS3

Module Description

LBASE Spatially allocate link-based emissions among grid cells.

PREAM Prepare non-link “roadway type” emissions for further processing.

PREPNT Prepare stationary extended idling emissions for further processing.
B-64

EPS3

Module Description

CNTLEM Apply controls to model strategies, apply adjustments, etc.

TMPRL Apply temporal profiles to extended idling emissions.

CHMSPL Chemically speciate emissions into NO, NO2, olefins, parrafins, etc.

GRDEM Sum emissions by grid cell for photochemical model input.

MRGUAM Merge and adjust multiple gridded files for photochemical model input.

The MOVES2010a model only estimates extended idling emissions for the diesel fuel 

combination long-haul truck category. Using a combination of SAS and LINUX code, these 

extended idling emissions were aggregated into a nine-county total and spatially assigned to 

known truck stop locations. The extended idling emissions were then processed through EPS3 

as if they were stationary low-level point sources. The summer weekday extended idling 

emissions by county are presented below in Table 34: 2006 Diesel Fuel Combination Long-Haul 

Truck Extended Idling Emissions for Nine-County DFW and Table 35: 2012 Diesel Fuel 

Combination Long-Haul Truck Extended Idling Emissions for Nine-County DFW. Greater detail 

on heavy-duty vehicle idling activity specific to Texas metropolitan areas can be found in reports 

located on the following web site: 

http://www.tceq.texas.gov/airquality/airmod/project/pj_report_mob.html.

Table 34: 2006 Diesel Fuel Combination Long-Haul Truck Extended Idling 

Emissions for Nine-County DFW

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 0.60 0.18 0.26

Dallas 2.00 0.59 0.88

Denton 0.59 0.17 0.26

Ellis 0.55 0.16 0.24

Johnson 0.05 0.01 0.02

Kaufman 1.15 0.34 0.51

Parker 1.11 0.33 0.49

Rockwall 0.44 0.13 0.19

Tarrant 0.80 0.24 0.35

Total 7.29 2.15 3.21

Table 35: 2012 Diesel Fuel Combination Long-Haul Truck Extended Idling 

Emissions for Nine-County DFW

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 1.04 0.20 0.49

Dallas 3.47 0.66 1.62

Denton 1.02 0.19 0.47

Ellis 0.96 0.18 0.45
B-65

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Johnson 0.08 0.02 0.04

Kaufman 1.99 0.38 0.93

Parker 1.91 0.37 0.89

Rockwall 0.76 0.15 0.36

Tarrant 1.38 0.26 0.65

Total 12.62 2.41 5.89

3.2.1

Based on an EPA memorandum entitled Texas Low Emission Diesel (LED) Fuel Benefits, 

September 27, 2001, a 4.8% NOX TxLED reduction should be claimed for 2002-and-newer 

diesel vehicles and a 6.2% NOX TxLED reduction should be claimed for 2001-and-older diesel 

vehicles. In order to determine the specific TxLED adjustment factors that should apply to each 

of the twelve diesel fuel source use types, MOVES2010a runs were performed to determine NOX

emissions rates by model year. By using these data, the 4.8% and 6.2% reduction factors were 

weighted according to NOX emission model year contributions for each diesel fuel source use

type. The FTP site at

Texas Low Emission Diesel Fuel Benefits

ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/mvs/txled/

contains more detail on this analysis. The resulting TxLED adjustment factors and benefits for 

both 2006 and 2012 are summarized in Table 36: Summary of 2006 Summer Weekday TxLED 

Benefits by Vehicle Type and Table 37: Summary of 2012 Summer Weekday TxLED Benefits by 

Vehicle Type, respectively. The TxLED adjustment factors were incorporated by NCTCOG into 

the on-road inventories by post-processing the MOVES2010a diesel fuel source use type NOX

emission rates.

Table 36: Summary of 2006 Summer Weekday TxLED Benefits by Vehicle Type

Diesel Fuel NOX Adjustment NOX Benefit

Source Use Type Reduction Factor (tpd)

Passenger Car 5.06% 0.9494 0.04

Passenger Truck 5.68% 0.9432 0.02

Light Commercial Truck 5.56% 0.9444 0.36

Intercity Bus 5.97% 0.9403 0.18

Transit Bus 5.94% 0.9406 0.04

School Bus 5.92% 0.9408 0.09

Refuse Truck 5.85% 0.9415 0.06

Single Unit Short-Haul Truck 5.31% 0.9469 0.82

Single Unit Long-Haul Truck 5.35% 0.9465 0.11

Motor Home 5.77% 0.9423 0.03

Combination Short-Haul Truck 5.82% 0.9418 1.78

Combination Long-Haul Truck 5.83% 0.9417 3.27

Total 6.81
B-66

Table 37: Summary of 2012 Summer Weekday TxLED Benefits by Vehicle Type

Diesel Fuel NOX Adjustment NOX Benefit

Source Use Type Reduction Factor (tpd)

Passenger Car 5.02% 0.9498 0.01

Passenger Truck 5.32% 0.9468 0.02

Light Commercial Truck 5.29% 0.9471 0.39

Intercity Bus 5.80% 0.9420 0.13

Transit Bus 5.77% 0.9423 0.03

School Bus 5.76% 0.9424 0.06

Refuse Truck 5.69% 0.9431 0.03

Single Unit Short-Haul Truck 5.04% 0.9496 0.49

Single Unit Long-Haul Truck 5.08% 0.9492 0.07

Motor Home 5.53% 0.9447 0.02

Combination Short-Haul Truck 5.47% 0.9453 0.86

Combination Long-Haul Truck 5.45% 0.9455 2.18

Total 4.29

3.3 Nine-County DFW Photochemical Modeling Input

The summer weekday on-road emissions by county that were input into the photochemical 

model are summarized below in Table 38: 2006 Summer Weekday On-Road Mobile Source 

Inventory by County and Table 39: 2012 Summer Weekday On-Road Mobile Source Inventory 

by County. These on-road inventory summaries are a combination of running exhaust, 

evaporative, off-network, and extended idling emissions. Differences by individual counties 

between these figures and those referenced above in Table 29 and Table 30 are due to the spatial 

reallocation of extended idling emissions presented above in Table 34 and Table 35. However, 

the nine-county total on-road emission estimates do not differ.

Table 38: 2006 Summer Weekday On-Road Mobile Source Inventory by County

DFW Area 

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 23.92 10.68 108.63

Dallas 104.06 46.18 510.42

Denton 22.37 9.29 93.23

Ellis 12.50 3.70 46.66

Johnson 9.10 3.65 44.84

Kaufman 10.29 2.83 36.59

Parker 9.60 2.94 34.37

Rockwall 4.04 1.42 15.73

Tarrant 63.23 30.33 318.63

Total 259.11 111.02 1,209.12
B-67

Table 39: 2012 Summer Weekday On-Road Mobile Source Inventory by County

DFW Area 

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 17.74 8.39 95.55

Dallas 69.27 31.83 390.53

Denton 16.18 7.14 80.03

Ellis 9.42 2.75 34.00

Johnson 6.41 2.56 30.15

Kaufman 8.32 2.20 27.06

Parker 7.76 2.23 24.16

Rockwall 3.00 1.10 11.21

Tarrant 43.30 22.28 263.06

Total 181.40 80.48 955.75

The total nine-county DFW on-road emissions input to the photochemical model by day type are 

summarized below in Table 40: 2006 On-Road Mobile Source Inventory by Day Type and Table 

41: 2012 On-Road Mobile Source Inventory by Day Type. Slight differences by day type between

these figures and those presented in Table 27 and Table 28 are due to how these on-road 

emission inventories are developed in Central Daylight Time (CDT), but must be processed for 

photochemical model input in Central Standard Time (CST). For example, the 11 PM – 12 AM 

CST emissions on a Friday evening are based on 12-1 AM CDT emissions from a Saturday.

Table 40: 2006 On-Road Mobile Source Inventory by Day Type

Day

Type

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Weekday 259.11 111.02 1,209.12

Friday 264.31 114.61 1,308.99

Saturday 189.98 103.25 1,131.33

Sunday 168.95 96.60 988.74

Monday 252.43 109.12 1,186.90

Table 41: 2012 On-Road Mobile Source Inventory by Day Type

Day

Type

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Weekday 181.40 80.48 955.75

Friday 182.24 81.87 1,013.94

Saturday 136.68 74.80 880.20

Sunday 124.84 71.37 784.28

Monday 175.33 78.97 930.45

For the on-road mobile inventory portion of the DFW subdomain, the EPS3 message files along 

with the gridded files input into the photochemical model for 2006 and 2012 are available on 

the following FTP sites, respectively:
B-68

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/eps3/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/eps3/2012/

Similar on-road mobile EPS3 message and gridded files for the Texas-only portion of the larger 

12 km modeling domain are available for 2006 and 2012, respectively, on the following FTP 

sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/eps3/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/eps3/2012/

Similar on-road mobile EPS3 message and gridded files for both the Texas and non-Texas 

portions of the larger 12 km modeling domain are available for 2006 and 2012, respectively, on 

the following FTP sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/USA/eps3/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/USA/eps3/2012/

3.4 Attainment Demonstration Motor Vehicle Emissions Budget

By definition, the future case on-road NOX and VOC emission estimates input into the final 

attainment demonstration photochemical modeling run should establish the motor vehicle 

emissions budget (MVEB). The 2012 summer weekday on-road emissions are the most 

representative day type for this purpose, and are presented below in Table 42: 2012 Attainment 

Demonstration MVEB for the Nine-County DFW Area. As shown, these 2012 figures match 

those provided by NCTCOG as summarized above in Table 28, Table 30, and Table 32. No 

emission reduction credits were taken for local transportation control measures (TCMs) and

voluntary mobile source emission reduction program (VMEP) strategies.

Table 42: 2012 Attainment Demonstration MVEB for the Nine-County DFW Area

Nine-County DFW Area

On-Road Emissions

NOX

(tpd)

VOC

(tpd)

2012 On-Road Inventory From NCTCOG (Table 28)

Includes RFG, Low RVP, I/M, and TxLED 181.40 80.48

The following pages contain graphical plots of the 2006 and 2012 on-road summer weekday 

NOX and VOC emissions for the greater DFW area. These plots are respectively entitled 

• Figure 16: 2006 DFW Summer Weekday NOX Emissions;

• Figure 17: 2006 DFW Summer Weekday VOC Emissions;

• Figure 18: 2012 DFW Summer Weekday NOX Emissions; and 

• Figure 19: 2012 DFW Summer Weekday VOC Emissions.
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Figure 16: 2006 DFW Summer Weekday NOX Emissions
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Figure 17: 2006 DFW Summer Weekday VOC Emissions
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Figure 18: 2012 DFW Summer Weekday NOX Emissions
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Figure 19: 2012 DFW Summer Weekday VOC Emissions
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3.5 On-Road Mobile Source Emissions Inventories for Non-DFW Areas

On-road emission inventories for 2006 and 2012 were also developed for portions of the 

modeling domain outside of the nine-county DFW area. For the three counties of Hood, Hunt, 

and Wise, a similar link-based inventory development approach was taken by NCTCOG based 

on local TDM output. Similar to the nine-county DFW area, on-road emissions were developed 

for the five day types of weekday, Friday, Saturday, Sunday, and Monday. More detail on the 

development of these Hood, Hunt, and Wise inventories is available on the following FTP sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/mvs/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/mvs/2012/

For the Texas counties outside of the DFW area, on-road emissions were developed by the Texas 

Transportation Institute (TTI) using Highway Performance Monitoring System (HPMS) data as 

the basis for VMT estimates. Summer season emission estimates were developed for the four 

day types of weekday, Friday, Saturday, and Sunday. Hourly emission rates from MOVES2010a

were coupled with county-level VMT estimates by roadway type for 2006 and 2012. More detail 

on the development of these HPMS-based on-road inventories is available on the following FTP 

sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/mvs/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/mvs/2012/

On-road emission estimates for non-Texas states within the photochemical modeling domain 

were developed for 2006 and 2012 using default runs from the MOVES2010a model, which is 

available at http://www.epa.gov/otaq/models/moves/index.htm. For both 2006 and 2012, 

default on-road emissions were estimated for the July weekday and weekend day type options 

available with MOVES2010a. More detail on the development of these default MOVES2010a onroad inventories is available on the following FTP sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/USA/mvs/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/USA/mvs/2012/

More detail on this analysis is documented in a presentation entitled Using the MOVES Model 

in Inventory Mode to Develop Regional On-Road Emission Inputs for Air Quality Modeling 

Applications, which was presented at an EPA workshop in June of 2011 and is available at 

http://www.epa.gov/otaq/models/moves/conference2011/inventory-regional-moves-2011.pdf. 

A summary of the different on-road emission estimation approaches by geographic area taken 

for this DFW SIP revision is provided in Table 43: On-Road Inventory Development by Area 

Within the Modeling Domain.

Table 43: On-Road Inventory Development by Area Within the Modeling Domain

On-Road Inventory

Development Parameter

DFW

Area

Non-DFW

Texas Counties

Non-Texas

States and Counties

VMT

Source

Travel Demand

Model (TDM)

Highway Performance

Monitoring System

MOVES2010a

Defaults

VMT

Resolution

Roadway Links

From TDM

19 Roadway

Types

12 Roadway

Types

Day

Types

Weekday, Friday,

Saturday, Sunday, and 

Monday

Weekday, Friday,

Saturday, and Sunday

Weekday and

Weekend
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On-Road Inventory

Development Parameter

DFW

Area

Non-DFW

Texas Counties

Non-Texas

States and Counties

Hourly Variation in

VMT? Yes Yes Yes

Roadway Speed

Distribution

Varies by Hour

and Link

Varies by Hour and

Roadway Type

MOVES2010a

Defaults

Spatial

Resolution Excellent Very

Good Good

Temporal

Resolution Excellent Very

Good Good

MOVES2010a Fuel and

Source Use Types

Gasoline and Diesel

13 Source Use Types

Gasoline and Diesel

13 Source Use Types

Gasoline and Diesel

13 Source Use Types
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4 NON-ROAD, OFF-ROAD, AND AREA SOURCE MODELING EMISSIONS

4.1 Texas Oil and Gas Production Emission Inventory Development

The area source oil and gas production EI was developed using a contractor-developed 

calculator that provided county-level emissions based on Texas Railroad Commission data for

production values of oil, condensate and natural gas (ERG, 2010). Non-Texas oil and gas 

production data is in the area source inventory (Section 4.7). Data from 2006 was provided for 

use in the base case and June 2010 data was provided as the latest available complete dataset for 

2012 future year development. Sources like compressors, condensate storage, heaters, and 

pneumatic devices dominated the emissions as illustrated in Table 44: 2006 Oil and Gas 

Production EI breakout.

Table 44: 2006 Oil and Gas Production EI breakout

area06_b2_oilgasp_9co (tpd)

Category NOx VOC CO

2-Cycle Lean Burn Compressor 1.29 0.04 0.36

4-Cycle Lean Burn Compressor 0.75 0.15 1.27

4-Cycle Rich Burn Compressor 46.18 0.97 8.55

4-Cycle Rich Burn Compressor w/ Catalyst 0.61 0.13 1.17

Condensate Tanks 0 40.57 0

Condensate Loading 0 0.33 0

Gas Heaters 1.15 0.06 0.96

Dehydrators 0 1.26 0

Gas Fugitives (grouped) 0 2.53 0

Gas Well Blowdowns 0 0.65 0

Gas Well Completions 0 2.96 0

Pumpjacks 0.07 0 0.03

Crude Tanks 0 0.22 0

Produced Water 0 0.45 0

Oil Well Blowdowns 0 0.06 0

Oil Fugitives (grouped) 0 0.04 0

Oil Well Completions 0 0.1 0

Oil Heaters 0.02 0 0.01

Oil Loading 0 0.02 0

Pneumatic Devices 0 21.54 0

Total (tpd) 50.07 72.1 12.36

The oil and gas production EI was projected from 2010 to 2012 using the simple assumption of 

10% growth for the 23 Barnett shale counties, 10% growth for the 10 Haynesville shale counties 

and 20% growth for the 45 Eagle Ford counties. 10% growth was also assigned to the remainder 

of the Texas counties in the domain. No additional controls were assumed between 2010 and 

2012. 

From 2006 to 2012 NOX emissions are projected to decline significantly primarily because of 

compressor engine NOX controls implemented in 2010 (Table 45: 2012 Oil and Gas Production 
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EI breakout). VOC emissions increase from 2006 to 2012, mainly due to an increase in 

pneumatic devices that follow the number or active wells.

Table 45: 2012 Oil and Gas Production EI breakout

area12_b2_oilgasp_9co

Category NOx(tpd) VOC CO

2-Cycle Lean Burn Compressor 0.25 0.13 1.07

4-Cycle Lean Burn Compressor 0.54 0.27 2.35

4-Cycle Rich Burn Compressor 1.16 0.05 1.11

4-Cycle Rich Burn Compressor w/ Catalyst 4.6 3.2 27.98

Condensate Tanks 0 33.51 0

Condensate Loading 0 0.27 0

Gas Heaters 3.04 0.17 2.56

Dehydrators 0 3.63 0

Gas Fugitives (grouped) 0 6.72 0

Gas Well Blowdowns 0 1.72 0

Gas Well Completions 0 3.31 0

Pumpjacks 0.1 0 0.05

Crude Tanks 0 0.38 0

Produced Water 0 2.2 0

Oil Well Blowdowns 0 0.09 0

Oil Fugitives (grouped) 0 0.06 0

Oil Well Completions 0 0.11 0

Oil Heaters 0.02 0 0.02

Oil Loading 0 0.04 0

Pneumatic Devices 0 57.2 0

Total (tpd) 9.71 113.07 35.14

The spatial distribution within counties for oil and gas production was built from Texas Railroad 

Commission data for active wellhead density. The number of active wells in a given model grid 

cell over the total number of active wells in the county assigned the proportionate amount of the 

county’s total emissions to that cell. Active wells for year-end 2006 were used for the base case 

(Figure 20: 2006 Oil and Gas Production NOX for the DFW 4 km Domain and Figure 21: 2006 

Oil and Gas Production cb05 VOC for the DFW 4 km Domain). Year-end 2010 wellhead 

densities were used to distribute the 2012 future case emissions (Figure 22: 2012 Oil and Gas 

Production NOX for the DFW 4 km Domain and Figure 23: 2012 Oil and Gas Production cb05 

VOC for the DFW 4 km Domain). Oil and gas production and drilling rigs were the only area or 

non- or off-road category where spatial surrogates were different for the base and future cases.
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Figure 20: 2006 Oil and Gas Production NOX for the DFW 4 km Domain
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Figure 21: 2006 Oil and Gas Production cb05 VOC for the DFW 4 km Domain
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Figure 22: 2012 Oil and Gas Production NOX for the DFW 4 km Domain
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Figure 23: 2012 Oil and Gas Production cb05 VOC for the DFW 4 km Domain
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4.2 Texas Drilling Rigs Emission Inventory Development

ERG (2009) developed a detailed Drilling Rig EI for every Texas County for the year 2008 that 

served as the basis for the 2006 and 2012 modeling EIs. Non-Texas oil and gas drilling is 

incorporated in the Non-road inventory (Section 4.6).

For the non-Barnett shale counties, the 2008 county-level drilling rig emissions were adjusted 

to 2006 according to the ratio of active drill rig counts in June 2006 and June 2008 from Baker 

Hughes (Baker Hughes, 2010). The 2006 and 2008 drill rig counts and the adjustment ratio in 

each of the Texas Railroad Commission (TRRC) districts is illustrated in Table 46: 2006 BakerHughes Rig Counts for TRRC Districts and Table 47: 2008 Baker-Hughes Rig Counts for TRRC 

Districts. TRRC districts 5, 7B, and 9 comprise the Barnett Shale. The TRRC districts are shown 

in Figure 24: TRRC Districts.

Table 46: 2006 Baker-Hughes Rig Counts for TRRC Districts

2006 - MONTHLY 

AVERAGES APR MAY JUN JUL AUG SEP OCT NOV DEC AVG

DISTRICT 1 22 22 23 21 21 24 21 17 17 20

DISTRICT 2 21 26 24 25 25 27 29 25 24 26

DISTRICT 3 69 67 65 65 60 58 52 59 63 61

DISTRICT 4 78 82 77 74 87 94 96 95 93 84

DISTRICT 5 131 133 131 135 146 141 133 137 143 133

DISTRICT 6 104 103 111 109 113 113 120 121 124 110

DISTRICT 7B 39 41 43 45 47 45 48 41 37 40

DISTRICT 7C 36 37 38 40 41 38 41 43 47 40

DISTRICT 8 81 84 91 96 103 96 96 102 101 90

DISTRICT 8A 29 27 30 29 23 26 26 25 26 28

DISTRICT 9 30 31 35 36 31 37 44 38 37 34

DISTRICT 10 68 70 66 70 76 78 75 64 56 68

ONSHORE 734 732

Table 47: 2008 Baker-Hughes Rig Counts for TRRC Districts

2008 - MONTHLY 

AVERAGES APR MAY JUN JUL AUG SEP OCT NOV DEC AVG

June 2006 

to 2008 

Adj. Factor

DISTRICT 1 25 29 25 19 22 27 27 27 20 24 1.087

DISTRICT 2 37 34 31 32 37 36 35 33 35 35 1.2917

DISTRICT 3 55 65 65 61 63 62 64 65 60 62 1

DISTRICT 4 92 92 97 92 93 91 88 92 81 91 1.2597

DISTRICT 5 186 180 182 185 185 187 185 169 160 181 1.3893

DISTRICT 6 121 120 122 124 126 132 134 127 130 125 1.0991

DISTRICT 7B 32 31 30 31 28 31 28 28 27 30 0.6977

DISTRICT 7C 71 69 70 70 72 71 62 67 59 64 1.8421

DISTRICT 8 128 132 136 140 137 132 127 126 108 128 1.4945
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2008 - MONTHLY 

AVERAGES APR MAY JUN JUL AUG SEP OCT NOV DEC AVG

June 2006 

to 2008 

Adj. Factor

DISTRICT 8A 23 26 28 28 32 27 28 29 30 26 0.9333

DISTRICT 9 35 38 42 44 41 42 41 45 45 42 1.2

DISTRICT 10 74 78 83 87 91 99 97 84 66 82 1.2576

ONSHORE 911 889 1.2411

Figure 24: TRRC Districts

For the 23 Barnett Shale counties, the annual average of weekly drill rig counts were used from 

RigData.com to adjust 2008 drill rig EI to 2006 as shown in Table 48: RigData.com data for 

Barnett Shale Rig Counts (RigData, 2009). The monthly averages are shown for reference.

Table 48: RigData.com data for Barnett Shale Rig Counts

RigData.com Average 

of Weekly Rig Counts 2006 2007 2008

2008 to 2006 

Adj. Factor

January 125 157 181 0.6906

February 131 162 180 0.7278

March 127 174 177 0.7175

April 133 174 183 0.7268

May 137 174 186 0.7366

June 141 174 190 0.7421

July 146 180 186 0.7849

August 150 182 187 0.8021

September 155 172 192 0.8073

October 150 185 190 0.7895

November 154 179 170 0.9059

December 156 182 162 0.9630

Annual 142 175 182 0.7802
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Projecting the 2008 data to 2006 (and to 2012) also required accounting for drill rig fleet 

turnover. The NONROAD model was run for drill rigs with flat equipment population to get 

emission ratios to account for federal rules on non-road engines. Table 49: 2006 DFW 9-county 

Drilling Rig EI shows the final 2006 drilling rig EI (tpd) for the DFW 9-county nonattainment 

area.

Table 49: 2006 DFW 9-county Drilling Rig EI

NONROAD_06_b11d_Drill_Rigs_9co (tpd)

Category NOX VOC CO

Drilling Rigs 18.1 1.27 17.4

Projecting drilling rig activity to 2012 had three steps. Baker-Hughes data similar to the 2008-

to-2006 projection was used to project to 2010 from 2008 by TRRC District (Table 50: BakerHughes 2008 to 2010 Rig Count Ratios by TRRC District). The rig count averages from 

September 2010 were the latest activity figures available at the time of EI development.

Table 50: Baker-Hughes 2008 to 2010 Rig Count Ratios by TRRC District

MONTHLY 

AVERAGES Sep-10 Jun-08

Jun 2008 to Sep 

2010 Adj. Factor

DISTRICT 1 62 25 2.47

DISTRICT 2 38 31 1.21

DISTRICT 3 48 65 0.74

DISTRICT 4 44 97 0.46

DISTRICT 5 82 182 0.45

DISTRICT 6 65 122 0.53

DISTRICT 7B 9 30 0.30

DISTRICT 7C 65 70 0.93

DISTRICT 8 168 136 1.24

DISTRICT 8A 30 28 1.07

DISTRICT 9 42 42 1.00

DISTRICT 10 68 83 0.82

ONSHORE 720 911 0.79

Due to the Barnett Shale’s proximity to the DFW nonattainment area, rig counts were 

downloaded for each of the 23 Barnett Shale counties (Baker-Hughes, 2010). Weekly rig counts 

were available into September 2010. The average of the last 10 weeks of rig counts for 2010 

were divided by the average of 2008 rig counts to project the 2008 EI to 2010. The county 

variation of rig activity within the Barnett Shale is notable as well the general decline in rig 

activity from 2008 (Table 51: Baker-Hughes Rig Counts for Barnett Shale Counties for 2008 and 

late 2010).
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Table 51: Baker-Hughes Rig Counts for Barnett Shale Counties for 2008 and late 

2010

Barnett Shale 

County Rig Counts

Average 

2008

Late 

2010

Late 2010 w/ 

min. rig fix

2008 to 2010 

Adj. Factor

Johnson 49 13.7 13.7 0.2796

Tarrant 46 33.1 33.1 0.7196

Wise 17 13.5 13.5 0.7941

Denton 16 9.8 9.8 0.6125

Parker 12 1.7 1.7 0.1417

Hill 11 0.1 1 0.0909

Hood 9 0.9 1 0.1111

Montague 5 13.7 13.7 2.7400

Palo Pinto 4 0 1 0.2500

Cooke 2 4.1 4.1 2.0500

Erath 3 0 1 0.3333

Jack 2 0 1 0.5000

Ellis 3 0.3 1 0.3333

Somervell 2 0 1 0.5000

Dallas 1.0 1.40 1.40 1.4000

Shackelford 0.3 0.40 0.40 1.3333

Stephens 1.3 0.1 1 0.7692

Other Counties (6) 3

Total 184.0 92.8 99.4

The second step in projecting drill rig emissions to 2012 from 2008 was to account for fleet 

turnover and federal controls on diesel engines for those four years. Lastly, mirroring the oil 

and gas production projection from 2010 to 2012, drilling rig activity growth was also assumed 

to be 10% for the Barnett shale counties, 10% for the Haynesville shale counties, 20% for the 

Eagle Ford counties, and 10% for the remainder of Texas. The decrease in drilling activity and 

the cleaner drill rig fleet account for the lower emissions in 2012 (Table 52: 2012 DFW 9-county 

Drilling Rig EI).

Table 52: 2012 DFW 9-county Drilling Rig EI

NONROAD_12_b11h_Drill_Rigs_9co (tpd)

Category NOX VOC CO

Drilling Rigs 8.71 0.62 15.87

Spatial surrogates for drilling rig activity were developed by mapping new wells in the TRRC 

data. Using GIS, the active wells at year-end 2005 were subtracted from the active wells at yearend 2006 to realize the geographic distribution of new wells for 2006. Figure 25: 2006 Drilling 

Rig NOX for the DFW 4 km Domain exhibits the spatial distribution of the drilling rig NOX

emissions for the June 2006 base case and baseline inventories. The new wells for 2010 were 

the latest available and used as the surrogate for the 2012 future case (Figure 26: 2012 Drilling 
B-85

Rig NOX for the DFW 4 km Domain). From 2006 to 2012 the location of drilling changed, 

including the eastward march of drilling in Tarrant County as shown in Figure 27: 2006 (left) 

and 2012 (right) Drilling Rig NOX for the DFW 4 km Domain. As Table 49 and Table 52 show, 

drilling rigs do not emit a significant amount of VOCs so they are not geographically plotted.
B-86

Figure 25: 2006 Drilling Rig NOX for the DFW 4 km Domain

Figure 26: 2012 Drilling Rig NOX for the DFW 4 km Domain
B-87

Figure 27: 2006 (left) and 2012 (right) Drilling Rig NOX for the DFW 4 km Domain

4.3 Louisiana Haynesville Shale Oil and Gas

As the Haynesville shale extends past the Texas border into Louisiana, TCEQ was able to use 

work by Environ for the Northeast Texas area to add oil and gas activity to the Louisiana EI

(Environ, 2008). These emissions (Figure 28: 2012 Louisiana Haynesville Shale Drill Rig NOX 

EI and Figure 29: 2012 Additional Haynesville Oil and Gas Production cb05 VOC) depict

additional emission for 2012 for a high level of development scenario developed by Environ. 

The emissions are in addition to the emissions in the regular Louisiana area and non-road EIs. 

The regular Louisiana EI was based on a 2005 National Emissions Inventory (NEI) and had no 

drill rig emissions, so the additional emissions for this category were more significant.
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Figure 28: 2012 Louisiana Haynesville Shale Drill Rig NOX EI
B-89

Figure 29: 2012 Additional Haynesville Oil and Gas Production cb05 VOC
B-90

4.4 Airports

The emissions for the airports in the nine-county area were provided by NCTCOG. The EIs 

include ground support equipment (GSE). Emissions were provided for 2006 and 2012 by 

airport (Table 53: 2006 DFW 9-county Airport EI and Table 54: 2012 DFW 9-county Airport 

EI). The TCEQ developed airport-specific surrogates so each airport’s emissions were 

distributed to the respective areal extent of the airport. Figure 30: 2006 DFW9-county airportspecific NOX EI and Figure 31: 2012 DFW 9-county airport-specific NOX EI illustrate the 2006 

and 2012 airport NOX EIs.

Airports outside of the nine-counties were developed at the county level and were drawn from 

TexAER for most of Texas. The Houston-Galveston-Brazoria (HGB) eight-county area is also 

airport-specific. The surrogates developed by TCEQ for the non-airport-specific area were 

landing and take-off (LTO)-area weighted. This weighting covers the areal extent of each 

airport, but assigns busier airports proportionately more of the total county emissions.

Table 53: 2006 DFW 9-county Airport EI

DFWairports06_9co

Category NOx VOC CO

Ground Support Equipment 1.85 0.57 16.25

Aircraft 9.15 4.52 26.83

Airport Total (tpd) 11 5.08 43.08

Table 54: 2012 DFW 9-county Airport EI

DFWairports12a_9co

Category NOx VOC CO

Ground Support Equipment 0.89 0.28 8.28

Aircraft 9.23 4.06 25.47

Airport Total (tpd) 10.12 4.34 33.75
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Figure 30: 2006 DFW9-county airport-specific NOX EI
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Figure 31: 2012 DFW 9-county airport-specific NOX EI
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4.5 Locomotives

Locomotive emissions were separated into line-haul and switchers to allow different spatial 

allocation. Switcher emissions were allocated to railyards and line-haul emissions were based 

on a Gross Ton Miles (GTM) distribution. The DFW nonattainment area county-level line-haul 

emissions were from the Texas Railroad Emission Inventory Model (TREIM) model (ERG, 

2009) and were allocated based on GTM distribution from work by Environ (2009). The GTM 

allocation properly allocates more emissions along the more heavily traveled rail lines in a way 

analogous to VMT distribution of automotive emissions. The non-DFW locomotive emissions 

were based on a 2005 TexAER inventory. The TCEQ created county-level surrogates of railyards 

to best allocate switcher locomotives spatially. Like all non-road diesel categories countyspecific NOX-humidity corrections were applied, as was TxLED. Temporal allocation was flat 

activity-wise; the variation seen in the figures depicting the locomotive emissions illustrate the 

hourly NOX-humidity factors that increase NOX with higher temperature and decrease them at 

higher specific humidity conditions. The 2006 and 2012 DFW locomotive emissions are 

detailed in Table 55: 2006 DFW 9-county Locomotive EI and Table 56: 2012 DFW 9-county 

Locomotive EI. The 2006 and 2012 spatial distribution of the line-haul and switcher locomotive 

NOX emissions are displayed in Figure 32: 2006 DFW 9-county Line-haul Locomotive NOX EI, 

Figure 33: 2006 DFW 9-county Switcher Locomotive NOX EI, Figure 34: 2012 DFW 9-county 

Line-haul Locomotive NOX EI, and Figure 35: 2012 DFW 9-county Switcher Locomotive NOX 

EI.

Table 55: 2006 DFW 9-county Locomotive EI

OFFR06_b7e_linehaul_switcher_9co (tpd)

Category NOx VOC CO

Line-haul Locomotives 14.93 0.74 2.07

Switcher Locomotives 13.72 0.93 1.85

Table 56: 2012 DFW 9-county Locomotive EI

OFFR12_b7e_linehaul_switcher_9co (tpd)

Category NOx VOC CO

Line-haul Locomotives 12.83 0.73 2.17

Switcher Locomotives 13.98 1 2.19
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Figure 32: 2006 DFW 9-county Line-haul Locomotive NOX EI
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Figure 33: 2006 DFW 9-county Switcher Locomotive NOX EI
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Figure 34: 2012 DFW 9-county Line-haul Locomotive NOX EI
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Figure 35: 2012 DFW 9-county Switcher Locomotive NOX EI
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4.6 Non-road/TexN

The non-road EI for Texas was calculated using the Texas-specific data for a version of the 

NONROAD model called TexN developed by ERG. The data developed includes updates to 

equipment populations for many major categories. This allows for a county-specific hourly 

NOX-humidity correction. TxLED factors were applied for the 110 counties of East Texas (ETx).

Table 57: 2006 NONROAD DFW 9-county EI breakout and Table 58: 2012 NONROAD DFW 9-

county EI breakout detail the non-road EI for 2006 and 2012. The geographic distribution of 

the non-road NOX and VOC emissions are shown in Figure 36: 2006 DFW 9-county Non-road 

NOX EI, Figure 37: 2006 DFW 9-county Non-road VOC EI, Figure 38: 2012 DFW 9-county 

Non-road NOX EI, and Figure 39: 2012 DFW 9-county Non-road VOC EI.

Table 57: 2006 NONROAD DFW 9-county EI breakout

NONROAD_06_b11a_9co (tpd)

Category NOx VOC CO

Recreational Equipment 0.23 5.58 21.78

Construction Equipment 32.06 7.11 61.27

Industrial Equipment 30.55 7.9 119.51

Commercial Lawn and Garden 1.78 9.04 74.63

Residential Lawn and Garden 1.27 12.02 136.75

Agricultural Equipment 10.16 1.21 17.62

Commercial Equipment 8.75 12.94 240.72

Recreational Boating 0.31 4.07 9.67

Railroad Maintenance 0.07 0.01 0.06

Total 85.18 59.88 682
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Figure 36: 2006 DFW 9-county Non-road NOX EI
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Figure 37: 2006 DFW 9-county Non-road VOC EI
B-101

Table 58: 2012 NONROAD DFW 9-county EI breakout

NONROAD_12_b11b_9co (tpd)

Category NOx VOC CO

Recreational Equipment 0.19 5.22 25.83

Construction Equipment 25.97 5.02 51.43

Industrial Equipment 20.29 4.01 73.9

Commercial Lawn and Garden 1.43 6.6 65.19

Residential Lawn and Garden 0.93 8.54 119.01

Agricultural Equipment 7.28 0.75 6.96

Commercial Equipment 7.35 9.45 213.53

Recreational Boating 0.33 3.03 9.3

Railroad Maintenance 0.06 0.01 0.05

Total 63.85 42.63 565.2
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Figure 38: 2012 DFW 9-county Non-road NOX EI
B-103

Figure 39: 2012 DFW 9-county Non-road VOC EI
B-104

4.7 Area Sources

The area source EI is based on a 2005 TexAER EI projected to 2006 and 2012 with REMIEGAS. The area source emissions are detailed by category in Table 59: 2006 Area Source DFW 

9-county EI breakout and Table 60: 2012 Area Source DFW 9-county EI breakout. The 

geographic distribution of the 2006 and 2012 area source EIs are shown in Figure 40: 2006 

DFW 9-county Area Source NOx EI, Figure 41: 2006 DFW 9-county Area Source cb05 VOC EI, 

Figure 42: 2012 DFW 9-county Area Source NOX EI, and Figure 43: 2012 DFW 9-county Area 

Source cb05 VOC EI.

Table 59: 2006 Area Source DFW 9-county EI breakout

area06_b8a_9co (tpd)

Category NOX VOC CO

Petroleum Products 0 42.89 0

Architectural Coating 0 34.36 0

Solvent Use 0 57.46 0

Surface Cleaning 0 1.03 0

Industrial Fuel Use 13.54 0.5 7.73

Residential Fuel Use 2.24 0.13 0.91

Auto Refinishing 0 3.87 0

Waste Treatment 0 10.14 0

Graphic Arts 0 1.38 0

Pesticide Use 0 0.01 0

Leaking Underground Storage Tanks 0 3.02 0

TRAFMAR 0 0.47 0

Surface Coating 0 49.72 0

Open Burning 0.47 2.85 42.09

Dry Cleaning 0 3.78 0

Asphalt Paving 0 0.65 0

Bakeries and Breweries 0 0.91 0

Total 16.25 213.18 50.73
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Figure 40: 2006 DFW 9-county Area Source NOx EI
B-106

Figure 41: 2006 DFW 9-county Area Source cb05 VOC EI
B-107

Table 60: 2012 Area Source DFW 9-county EI breakout

area12_b8a_9co (tpd)

Category NOx VOC CO

Petroleum Products 0 45.02 0

Architectural Coating 0 40.46 0

Solvent Use 0 64.11 0

Surface Cleaning 0 1.26 0

Industrial Fuel Use 15.27 0.57 8.83

Residential Fuel Use 2.36 0.13 0.95

Auto Refinishing 0 4.64 0

Waste Treatment 0 11.24 0

Graphic Arts 0 1.47 0

Pesticide Use 0 0.01 0

Leaking Underground Storage Tanks 0 3.13 0

TRAFMAR 0 0.49 0

Surface Coating 0 58.5 0

Open Burning 0.53 3.15 46.48

Dry Cleaning 0 4.06 0

Asphalt Paving 0 0.79 0

Bakeries and Breweries 0 0.97 0

Total 18.17 240.03 56.26
B-108

Figure 42: 2012 DFW 9-county Area Source NOX EI
B-109

Figure 43: 2012 DFW 9-county Area Source cb05 VOC EI
B-110

4.8 Ship Emissions

Contract work by Environ and data from the Port of Houston were integrated to update the HGB 

shipping EI to 2007 ship movements. Environ work also allowed improved emissions treatment 

for the Gulf of Mexico and the Atlantic Ocean in the modeling domains to be based on actual 

ship location data and ship traffic data rather than simple shipping lanes. EPA near-port data 

was used near shore to pick-up where the Ship Traffic, Energy and Environment Model 

(STEEM) data ended to improve near-shore ship modeling. No commercial shipping exists in 

the DFW 4 km domain as shown in Figure 44: 2006 STEEM Ship Emissions for Gulf of Mexico 

for 12 km Domain.
B-111

Figure 44: 2006 STEEM Ship Emissions for Gulf of Mexico for 12 km Domain
B-112

5 BIOGENIC MODELING EMISSIONS

For development of the biogenic emissions, the TCEQ used version 3.1 of the Global Biosphere 

Emissions and Interactions System (GloBEIS3.1), available at http://www.globeis.com/. 

GloBEIS3.1 incorporates detailed locality-specific land-use data to generate the mix and density 

of vegetative species. GloBEIS tables were appended to include species and leaf mass densities 

specific to the 30-meter resolved land cover generated by Texas A&M University under funding

from the TCEQ (Popescu, 2010). In addition, solar radiation data from Geostationary 

Operational Environmental Satellite (GOES) satellite imagery, which is used to generate the 

photosynthetically-active solar radiation (PAR), was input to the GloBEIS3.1 model. Further, 

the GloBEIS3.1 model used hourly temperature data generated from weather station data.

Land cover data for the 4 km DFW modeling domain is a subset of land cover generated from a 

project funded by the TCEQ and executed by the Texas A&M Spatial Sciences Laboratory 

(Popescu, 2010). This land cover was created from Landscape Fire and Resource Management 

Planning Tools Project (LANDFIRE) data hosted by the United States Geological Survey 

(USGS). The data were reclassified into Texas Land Classification System classes, and refined 

using ancillary data such as classified Landsat Thematic Mapper (TM) imagery and Common 

Land Unit (CLU) data provided by the United States Department of Agriculture (USDA). Figure 

45: TCEQ Land Cover for the 4 km DFW CAMx Domain illustrates the land cover used for the 4 

km DFW domain. 
B-113

Figure 45: TCEQ Land Cover for the 4 km DFW CAMx Domain
B-114

The 12 km and 36 km non-Texas portions of the modeling domain were obtained from Version 3 

of the Biogenic Emissions Landuse Data (BELD3; Kinnee et al., 1997), which is a vegetation 

database for the entire North American continent prepared specifically for creating biogenic 

emission inventories. Land-use data for the Mexico portion of the 12 km modeling domain were 

obtained from a joint effort between the University of Monterrey and Georgia Tech (MendozaDominguez et al., 2000). Land-use data for the Texas portion of the 12 km domain were 

obtained from the Texas vegetation database (Wiedinmyer et al., 2001), which was derived 

from:

• Texas Parks and Wildlife vegetation data;

• agricultural statistics from the National Agricultural Statistics Survey; and

• field surveys carried out in 1999.

The episode-specific PAR data input to GloBEIS3.1 were obtained from the website

(http://metosrv2.umd.edu/~srb/gcip/cgi-bin/historic.cgi) operated by the Global Energy and 

Water Cycle Experiment (GEWEX) Continental International Project (GCIP) and GEWEX 

Americas Prediction Project (GAPP). These data were available at half-degree resolution and 

were reprocessed to spatially match the grid structure of the modeling domain. These data are 

derived from hourly GOES satellite imagery of cloud cover, which have been processed with a 

solar irradiation model (Pinker and Laszlo, 1992).

The episode-specific temperature data were obtained from weather stations throughout the U.S., 

including data from the National Weather Service (NWS), the EPA Aerometric Information 

Retrieval System (AIRS) air quality database, the National Buoy Data Center, the Texas A&M 

Crop Weather Program, the Louisiana Agricultural Information Service, and the Texas Coastal 

Oceanographic Observation Network. The organizations providing these meteorological data 

sets typically run thorough quality assurance checks, but the TCEQ further reviewed them for 

possible anomalies. Kriging algorithms were used with Statistical Analysis Software (SAS) to 

prepare the hourly temperature fields. The estimated hourly values were interpolated with a 

variogram that appropriately fits the inherent degree of variation.

The GloBEIS3.1 model was run for each of the ozone episode days, from May 31 through July 2, 

2006. Within the 4 km DFW modeling domain, during this period, there were 17 days 

exceeding the 1997 ozone standard.

For quality assurance purposes, an emissions summary file was created showing the hourly 

domain-wide total emissions of NOX, CO, isoprene, monoterpenes, and other VOCs to allow 

quick comparisons over different episode days. An example of the hourly emissions file is 

shown in Table 61: Example GloBEIS3.1 Hourly Biogenic Emissions Report for June 2, 2006. 

An additional quality assurance step involved review of the model configuration file which lists 

the various GloBEIS3.1 input settings. Since biogenic emissions are dependent upon the 

meteorological conditions on a given day, the same episode-specific emissions for the 2006 

baseline were used in the 2012 future case modeling scenarios. The summary of biogenic 

emissions, by day, is shown in Table 62: Daily Summary of Biogenic Emissions for the 2006 

DFW Ozone Episode..
B-115

Table 61: Example GloBEIS3.1 Hourly Biogenic Emissions Report for June 2, 2006

year day hour

Isoprene 

(tons)

Monoterpenes 

(tons)

Other VOCs 

(tons)

Nitrogen 

Oxides (tons)

2006 183 0 0 7.06 13.16 1.68

2006 183 1 0 6.99 12.89 1.67

2006 183 2 0 6.89 12.73 1.66

2006 183 3 0 6.84 12.56 1.64

2006 183 4 0 6.87 12.57 1.63

2006 183 5 6.16 6.9 12.59 1.64

2006 183 6 31.25 7.5 13.62 1.73

2006 183 7 48.55 8.52 15.38 1.88

2006 183 8 68.72 9.67 17.65 2.04

2006 183 9 94.13 10.78 19.76 2.19

2006 183 10 121.08 12.32 22.86 2.39

2006 183 11 141.72 13.79 25.5 2.58

2006 183 12 156.37 14.78 27.56 2.72

2006 183 13 168.6 15.64 29.39 2.85

2006 183 14 171.53 16.47 30.58 2.95

2006 183 15 161.75 16.47 30.77 2.96

2006 183 16 119.71 14.46 27.64 2.77

2006 183 17 99.05 13.82 26.38 2.66

2006 183 18 61.76 11.87 22.85 2.4

2006 183 19 6.57 10.4 19.86 2.18

2006 183 20 0 9.42 17.7 2.06

2006 183 21 0 8.91 16.62 1.98

2006 183 22 0 8.48 15.86 1.9

2006 183 23 0 7.99 14.94 1.84

Daily 

Total:

1,456.95 252.84 471.42 52
B-116

Table 62: Daily Summary of Biogenic Emissions for the 2006 DFW Ozone Episode.

Ozone 

Episode 

Day

Isoprene 

(tons/day)

Monoterpenes 

(tons/day)

Other VOC 

(tons/day)

Nitrogen 

Oxides 

(tons/day)

5/31/2006 674.74 182.89 377.16 45.78

6/1/2006 768.64 190.12 389.02 45.91

6/2/2006 1070.42 219.21 448.10 49.88

6/3/2006 1127.65 221.98 458.90 50.05

6/4/2006 1373.30 260.53 563.99 55.96

6/5/2006 1318.99 255.75 575.43 55.58

6/6/2006 1507.36 285.68 621.49 59.49

6/7/2006 1397.51 267.31 567.70 56.23

6/8/2006 1447.72 277.47 576.81 58.02

6/9/2006 1581.51 300.30 631.53 61.12

6/10/2006 1677.70 318.11 671.59 63.94

6/11/2006 1511.27 292.92 627.17 60.60

6/12/2006 1581.42 306.15 640.00 61.84

6/13/2006 1467.57 283.35 614.74 58.89

6/14/2006 1253.64 243.76 517.91 53.36

6/15/2006 1447.18 282.03 595.70 58.57

6/16/2006 1165.28 244.81 544.78 55.00

6/17/2006 881.47 216.68 465.57 50.46

6/18/2006 1051.34 221.03 475.37 51.98

6/19/2006 1182.95 233.17 504.02 53.26

6/20/2006 1000.41 227.04 460.39 51.94

6/21/2006 1237.81 261.11 537.05 56.81

6/22/2006 1162.76 262.76 537.36 57.64

6/23/2006 1023.72 242.51 493.36 53.66

6/24/2006 964.14 232.38 489.65 53.30

6/25/2006 1406.54 273.72 561.85 58.01

6/26/2006 967.87 210.55 423.98 48.93

6/27/2006 1081.67 211.93 434.98 49.07

6/28/2006 1285.15 238.95 494.50 53.22

6/29/2006 1300.00 251.14 515.37 55.05

6/30/2006 1344.04 264.98 546.21 56.98

7/1/2006 1208.53 245.35 518.47 55.02

7/2/2006 1000.67 223.06 467.54 51.98
B-117

5.1 Future Improvements

Future improvements to the biogenics modeling for DFW include improved land cover. The 

TCEQ funded Texas A&M to produce a seamless 30 m resolution land cover base map for the 

TCEQ 12 km meteorological domain. The 12 km photochemical model domain is a subset of the 

larger meteorological domain, and so this land cover will be used for future 12 km and 4 km

biogenic emission modeling for DFW. The U.S. portion of the new land cover is founded on data 

from the U.S. Government’s LANDFIRE program, and Landsat 5 data for the Mexican portion of 

the land cover. The resulting seamless dataset is illustrated in Figure 46: New TCEQ land cover 

produced by Texas A&M University for the 12 km meteorological modeling domain.

Figure 46: New TCEQ land cover produced by Texas A&M University for the 12 km

meteorological modeling domain

In 2011, the TCEQ plans to append GloBEIS vegetation data tables to include data from the

United States Department of Agriculture (USDA) Forest Service Forest Inventory Analysis (FIA) 

data. Using GIS, FIA tree and plot-level forestry data will be spatially merged with mapped 

categories in the new land cover dataset. Analysis of this merged data will reveal a realistic 

species composition within each forested class and provide data useful for calculating average 

leaf mass density for each species using allometric equations published by the US Forest Service. 
B-118

The TCEQ has funded another project to map the urban forest in Texas’ major urban areas. This 

will be accomplished using high resolution aerial imagery and, where necessary and available, 

light detection and ranging data (Lidar). The resulting urban classes will reflect the presence 

and composition of forested areas in mapping classes currently described as “Developed Open 

Space,” “Developed Low Intensity,” “Developed Medium Intensity,” or “Developed High 

Intensity.” While the urban areas are relatively small in comparison to the rest of the state, the 

urban forest they contain is likely to play an important role in the photochemistry and 

meteorology of these areas. 

The GloBEIS model was enhanced in mid-2010 by Environ (Yarwood, 2010). The new model, 

GloBEIS 3.5, has additional functionality, which includes:

• Reporting of sesquiterpenes in the native emissions output;

• Capability to model multiple contiguous days in a given model run; and

• Automatic generation of logs reporting input parameters for each day within the model run
B-119

6 REFERENCES

Baker Hughes, 2010. Baker Hughes Investor Relations - Rig Counts, 

http://investor.shareholder.com/bhi/rig_counts/rc_index.cfm.

Environ, 2009. Development of Emissions Inventories for Natural Gas Exploration and 

Production Activity in the Haynesville Shale, Draft Report to the Northeast Texas Air Care, 

http://www.netac.org/UserFiles/File/NETAC/9_29_09/Enclosure_2b.pdf, August 31, 2009.

Environ, 2010. “Enhancement of GloBEIS.” Accessed February 2, 2011. 

http://www.tceq.texas.gov/airquality/airmod/project/pj_report_ei.html.

ERG, 2007. Tier-Specific Locomotive Engine Update, Final Report to the Texas Commission on 

Environmental Quality (TCEQ), Contract No. 582-7-84003-FY07-04, Eastern Research Group, 

Inc., Morrisville, NC.

Kinnee et al., 1997. United States land use inventory for estimating biogenic ozone precursor 

emissions. Ecological Appl. 7(1): 46-58.

Mendoza-Dominguez et al., 2000. Modeling and direct sensitivity analysis of biogenic 

emissions impacts on regional ozone formation in the Mexico-U.S. border area, J. Air & Waste 

Manage. Assoc., 50: 21-31.

Pinker, R.T. and I. Laszlo, 1992. Modeling surface solar irradiance for satellite applications on a 

global scale. J. Appl. Meteor., 31, 194-211.

Popescu, 2010. “Expansion of Texas Land Use/Land Cover through Class Crosswalking and 

LiDAR Parameterization of Arboreal Vegetation”. Accessed February 2, 2011. 

http://www.tceq.texas.gov/airquality/airmod/project/pj_report_ei.html.

RigData, 2009. RigData Barnett Shale Rig Count, 

http://www.barnettshalenews.com/documents/RigData%20Barnett%20Shale%20Rig%20Coun

t%20Booklet%20Barnett%20Shale%20EXPO%203-11-2009.pdf.

Wiedinmyer et al., 2001. A land use database and examples of biogenic isoprene emission 

estimates for the state of Texas, USA, Atmos. Environ. 35: 6465-6477.
B-120

ATTACHMENT 1: TEXAS 2010 CAIR NOX ALLOCATIONS

Table 63, Att. 1: Texas 2010 CAIR NOX Allocations

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100215490 Copper Station 9 1 0.123

RN101062255 Oklaunion Power Station 127 1 9.292

RN100542927 Limestone 298 LIM1 12.137

RN100542927 Limestone 298 LIM2 10.975

RN100226638 E S Joslin 3436 1 0.506

RN102565843 J L Bates 3438 1 0.385

RN102565843 J L Bates 3438 2 0.361

RN100213909 Laredo 3439 1 0.118

RN100213909 Laredo 3439 2 0.115

RN100213909 Laredo 3439 3 0.631

RN100213909 Laredo 3439 4 0.030

RN100213909 Laredo 3439 5 0.030

RN100215979 Lon C Hill 3440 1 0.060

RN100215979 Lon C Hill 3440 2 0.153

RN100215979 Lon C Hill 3440 3 0.353

RN100215979 Lon C Hill 3440 4 0.667

RN100552181 Nueces Bay 3441 5 0.016

RN100552181 Nueces Bay 3441 6 0.383

RN100552181 Nueces Bay 3441 7 1.476

RN102560687 La Palma 3442 6 0.831

RN102560687 La Palma 3442 7 0.044

RN100214980 Victoria Power Station 3443 6 0.049

RN100214980 Victoria Power Station 3443 7 0.161

RN100214980 Victoria Power Station 3443 8 0.547

RN100214980 Victoria Power Station 3443 9 0.066

RN100673490 Lake Hubbard 3452 1 0.757

RN100673490 Lake Hubbard 3452 2 1.757

RN101559235 Mountain Creek Gen 3453 2 0.046

RN101559235 Mountain Creek Gen 3453 3A 0.057

RN101559235 Mountain Creek Gen 3453 3B 0.036

RN101559235 Mountain Creek Gen 3453 6 0.224

RN101559235 Mountain Creek Gen 3453 7 0.281

RN101559235 Mountain Creek Gen 3453 8 1.372

RN101559854 North Lake 3454 1 0.402

RN101559854 North Lake 3454 2 0.448

RN101559854 North Lake 3454 3 0.943

RN100804301 Parkdale 3455 1 0.112

RN100804301 Parkdale 3455 2 0.172
B-121

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100804301 Parkdale 3455 3 0.219

RN100211309 NEWMAN 3456 4 0.000

RN100211309 NEWMAN 3456 5 0.000

RN100211309 Newman 3456 1 0.372

RN100211309 Newman 3456 2 0.396

RN100211309 Newman 3456 3 0.525

RN100211309 Newman 3456 **4 0.518

RN100211309 Newman 3456 **5 0.611

RN100211309 Newman 3456 GT-6A 0.052

RN100211309 Newman 3456 GT-6B 0.049

RN100226877 Lewis Creek 3457 1 1.484

RN100226877 Lewis Creek 3457 2 1.443

RN102513041 Sabine 3459 1 1.175

RN102513041 Sabine 3459 2 1.200

RN102513041 Sabine 3459 3 1.924

RN102513041 Sabine 3459 4 2.451

RN102513041 Sabine 3459 5 2.091

RN100825371 Cedar Bayou 3460 CBY1 1.801

RN100825371 Cedar Bayou 3460 CBY2 1.938

RN100825371 Cedar Bayou 3460 CBY3 2.807

RN100825371 Cedar Bayou 4 3460 CBY41 0.077

RN100825371 Cedar Bayou 5 3460 CBY42 0.066

RN100542877 AES Western Power 3461 DWP9 0.167

RN100542851 Greens Bayou 3464 GBY5 0.670

RN100542851 Greens Bayou 3464 GBY73 0.022

RN100542851 Greens Bayou 3464 GBY74 0.022

RN100542851 Greens Bayou 3464 GBY81 0.025

RN100542851 Greens Bayou 3464 GBY82 0.025

RN100542851 Greens Bayou 3464 GBY83 0.025

RN100542851 Greens Bayou 3464 GBY84 0.030

RN101062826 P H Robinson 3466 PHR1 1.487

RN101062826 P H Robinson 3466 PHR2 1.626

RN101062826 P H Robinson 3466 PHR3 1.476

RN101062826 P H Robinson 3466 PHR4 1.875

RN100825389 Sam Bertron 3468 SRB3 0.542

RN100825389 Sam Bertron 3468 SRB4 0.485

RN100825389 Sam Bertron 3468 SRB1 0.208

RN100825389 Sam Bertron 3468 SRB2 0.284

RN100825389 SAM BERTRON 3468 SRB3 0.000

RN100825389 SAM BERTRON 3468 SRB4 0.000

RN100542885 T H Wharton 3469 THW2 0.432

RN100542885 T H Wharton 3469 THW31 0.290
B-122

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100542885 T H Wharton 3469 THW32 0.251

RN100542885 T H Wharton 3469 THW33 0.268

RN100542885 T H Wharton 3469 THW34 0.276

RN100542885 T H Wharton 3469 THW41 0.268

RN100542885 T H Wharton 3469 THW42 0.243

RN100542885 T H Wharton 3469 THW43 0.273

RN100542885 T H Wharton 3469 THW44 0.271

RN100542885 T H Wharton 3469 THW51 0.038

RN100542885 T H Wharton 3469 THW52 0.041

RN100542885 T H Wharton 3469 THW53 0.046

RN100542885 T H Wharton 3469 THW54 0.044

RN100542885 T H Wharton 3469 THW55 0.044

RN100542885 T H Wharton 3469 THW56 0.038

RN100888312 W A Parish 3470 WAP8 9.441

RN100888312 W A Parish 3470 WAP1 0.281

RN100888312 W A Parish 3470 WAP2 0.205

RN100888312 W A Parish 3470 WAP3 0.530

RN100888312 W A Parish 3470 WAP4 1.369

RN100888312 W A Parish 3470 WAP5 9.942

RN100888312 W A Parish 3470 WAP6 9.499

RN100888312 W A Parish 3470 WAP7 8.942

RN100542992 Webster 3471 WEB3 0.440

RN102156916 Knox Lee Power Plant 3476 2 0.011

RN102156916 Knox Lee Power Plant 3476 3 0.016

RN102156916 Knox Lee Power Plant 3476 4 0.090

RN102156916 Knox Lee Power Plant 3476 5 1.038

RN100542620 Lone Star Power Plan 3477 1 0.030

RN100542596 Wilkes Power Plant 3478 1 0.290

RN100542596 Wilkes Power Plant 3478 2 0.997

RN100542596 Wilkes Power Plant 3478 3 1.041

RN100224765 Jones Station 3482 151B 1.432

RN100224765 Jones Station 3482 152B 1.254

RN100224955 Moore County Station 3483 3 0.055

RN100224641 Nichols Station 3484 141B 0.312

RN100224641 Nichols Station 3484 142B 0.303

RN100224641 Nichols Station 3484 143B 0.634

RN100224419 Plant X 3485 111B 0.079

RN100224419 Plant X 3485 112B 0.183

RN100224419 Plant X 3485 113B 0.281

RN100224419 Plant X 3485 114B 0.888

RN100693308 Eagle Mountain 3489 1 0.161

RN100693308 Eagle Mountain 3489 2 0.295
B-123

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100693308 Eagle Mountain 3489 3 0.730

RN102563426 Graham 3490 1 0.716

RN102563426 Graham 3490 2 1.060

RN102336906 Handley Generating Sta 3491 1A 0.230

RN102336906 Handley Generating Sta 3491 1B 0.186

RN102336906 Handley Generating Sta 3491 2 0.150

RN102336906 Handley Generating Sta 3491 3 1.437

RN102336906 Handley Generating Sta 3491 4 0.929

RN102336906 Handley Generating Sta 3491 5 0.839

RN102285848 Morgan Creek 3492 3 0.011

RN102285848 Morgan Creek 3492 4 0.082

RN102285848 Morgan Creek 3492 5 0.451

RN102285848 Morgan Creek 3492 6 1.929

RN102285848 Morgan Creek 3492 CT1 0.016

RN102285848 Morgan Creek 3492 CT2 0.016

RN102285848 Morgan Creek 3492 CT3 0.019

RN102285848 Morgan Creek 3492 CT4 0.030

RN102285848 Morgan Creek 3492 CT5 0.022

RN102285848 Morgan Creek 3492 CT6 0.022

RN102764933 North Main 3493 4 0.101

RN102183969 Permian Basin 3494 5 0.258

RN102183969 Permian Basin 3494 6 2.577

RN102183969 Permian Basin 3494 CT1 0.025

RN102183969 Permian Basin 3494 CT2 0.025

RN102183969 Permian Basin 3494 CT3 0.025

RN102183969 Permian Basin 3494 CT4 0.030

RN102183969 Permian Basin 3494 CT5 0.025

RN101198059 Big Brown 3497 1 9.806

RN101198059 Big Brown 3497 2 9.404

RN100784735 Collin 3500 1 0.249

RN101698520 Lake Creek 3502 1 0.161

RN101698520 Lake Creek 3502 2 0.571

RN101983344 River Crest 3503 1 0.082

RN101621449 Stryker Creek 3504 1 0.361

RN101621449 Stryker Creek 3504 2 1.694

RN102566494 Tradinghouse 3506 1 1.667

RN102566494 Tradinghouse 3506 2 3.055

RN101943868 Trinidad 3507 9 0.413

RN102285855 Valley (TXU) 3508 1 0.402

RN102285855 Valley (TXU) 3508 2 1.820

RN102285855 Valley (TXU) 3508 3 0.525

RN102688439 Oak Creek Power Sta 3523 1 0.292
B-124

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100215300 Paint Creek Power Sta 3524 1 0.049

RN100215300 Paint Creek Power Sta 3524 2 0.052

RN100215300 Paint Creek Power Sta 3524 3 0.038

RN100215300 Paint Creek Power Sta 3524 4 0.271

RN102688835 Rio Pecos Power Station 3526 5 0.096

RN102688835 Rio Pecos Power Station 3526 6 0.424

RN101531226 San Angelo Power Station 3527 2 0.721

RN100219872 Decker Creek 3548 1 1.041

RN100219872 Decker Creek 3548 2 1.205

RN100219872 Decker Creek 3548 GT1 0.011

RN100219872 Decker Creek 3548 GT2 0.016

RN100219872 Decker Creek 3548 GT3 0.016

RN100219872 Decker Creek 3548 GT4 0.011

RN100220045 Holly Street 3549 1 0.087

RN100220045 Holly Street 3549 2 0.044

RN100220045 Holly Street 3549 3 0.342

RN100220045 Holly Street 3549 4 0.473

RN100219450 Silas Ray 3559 10 0.008

RN100219450 Silas Ray 3559 8 0.005

RN100219450 Silas Ray 3559 9 0.098

RN101612851 Bryan 3561 6 0.068

RN102528510 C E Newman 3574 BW5 0.022

RN100219203 Ray Olinger 3576 BW2 0.456

RN100219203 Ray Olinger 3576 BW3 0.473

RN100219203 Ray Olinger 3576 CE1 0.243

RN100219203 Ray Olinger 3576 GE4 0.005

RN102038486 Sim Gideon 3601 1 0.249

RN102038486 Sim Gideon 3601 2 0.306

RN102038486 Sim Gideon 3601 3 1.260

RN102545142 Alex Ty Cooke Genera 3602 1 0.142

RN102545142 Alex Ty Cooke Genera 3602 2 0.118

RN100217678 J Robert Massengale 3604 GT1 0.205

RN100217439 Leon Creek 3609 3 0.022

RN100217439 Leon Creek 3609 4 0.036

RN100217439 Leon Creek 3609 CGT1 0.005

RN100217439 Leon Creek 3609 CGT2 0.008

RN100217439 Leon Creek 3609 CGT3 0.008

RN100217439 Leon Creek 3609 CGT4 0.008

RN100217173 Mission Road 3610 3 0.033

RN100217975 O W Sommers 3611 1 1.069

RN100217975 O W Sommers 3611 2 0.820

RN100217835 V H Braunig 3612 1 0.383
B-125

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100217835 V H Braunig 3612 2 0.249

RN100217835 V H Braunig 3612 3 0.820

RN100217835 V H Braunig 3612 CT01 0.831

RN100217835 V H Braunig 3612 CT02 0.793

RN100217611 W B Tuttle 3613 1 0.019

RN100217611 W B Tuttle 3613 2 0.055

RN100217611 W B Tuttle 3613 3 0.052

RN100217611 W B Tuttle 3613 4 0.096

RN100216993 North Texas 3627 3 0.011

RN102033891 R W Miller 3628 1 0.128

RN102033891 R W Miller 3628 2 0.429

RN102033891 R W Miller 3628 3 0.719

RN102033891 R W Miller 3628 4 0.115

RN102033891 R W Miller 3628 5 0.109

RN100222652 Sam Rayburn Plant 3631 CT7 0.025

RN100222652 Sam Rayburn Plant 3631 CT8 0.025

RN100222652 Sam Rayburn Plant 3631 CT9 0.025

RN100223023 Power Lane Steam Plant 4195 2 0.008

RN100223023 Power Lane Steam Plant 4195 3 0.036

RN100214766 Spencer 4266 4 0.098

RN100214766 Spencer 4266 5 0.150

RN100219468 T C Ferguson 4937 1 1.227

RN100215557 Fort Phantom Power Sta 4938 1 0.568

RN100215557 Fort Phantom Power Sta 4938 2 0.787

RN100642040 Barney M. Davis 4939 1 1.427

RN100642040 Barney M. Davis 4939 2 1.752

RN100214550 Gibbons Creek Steam 6136 1 6.359

RN100213370 Welsh Power Plant 6139 1 8.343

RN100213370 Welsh Power Plant 6139 2 8.026

RN100213370 Welsh Power Plant 6139 3 8.141

RN102583093 Martin Lake 6146 1 11.965

RN102583093 Martin Lake 6146 2 11.626

RN102583093 Martin Lake 6146 3 12.549

RN102285921 Monticello 6147 1 9.117

RN102285921 Monticello 6147 2 9.243

RN102285921 Monticello 6147 3 11.729

RN100226919 Coleto Creek 6178 1 8.890

RN100226844 Sam Seymour 6179 1 8.374

RN100226844 Sam Seymour 6179 2 8.751

RN100226844 Sam Seymour 6179 3 7.023

RN100216191 Oak Grove 6180 1 0.184

RN100217975 J T Deely 6181 1 6.797
B-126

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100217975 J T Deely 6181 2 6.646

RN100226539 San Miguel 6183 SM-1 6.920

RN100224849 Harrington Station 6193 061B 6.357

RN100224849 Harrington Station 6193 062B 6.220

RN100224849 Harrington Station 6193 063B 6.234

RN100224534 Tolk Station 6194 171B 8.259

RN100224534 Tolk Station 6194 172B 8.674

RN102166576 Roland C. Dansby Power 6243 1 0.380

RN101611556 Roland C. Dansby Power 6243 2 0.005

RN102147881 Sandow 6648 4 9.945

RN100226570 Twin Oaks Power, LP 7030 U1 2.449

RN100226570 Twin Oaks Power, LP 7030 U2 2.577

RN100217975 J K Spruce 7097 **1 9.521

RN100542901 San Jacinto Steam El 7325 SJS1 0.891

RN100542901 San Jacinto Steam El 7325 SJS2 0.891

RN100224989 Calpine Hidalgo Ener 7762 HRSG1 0.801

RN100224989 Calpine Hidalgo Ener 7762 HRSG2 0.855

RN100215052 Sand Hill Energy Center 7900 SH1 0.019

RN100215052 Sand Hill Energy Center 7900 SH2 0.016

RN100215052 Sand Hill Energy Center 7900 SH3 0.016

RN100215052 Sand Hill Energy Center 7900 SH4 0.014

RN100215052 Sand Hill Energy Center 7900 SH5 0.307

RN100214287 H W Pirkey Power Plant 7902 1 9.901

RN100664812 Decordova 8063 1 3.558

RN100664812 Decordova 8063 CT1 0.049

RN100664812 Decordova 8063 CT2 0.046

RN100664812 Decordova 8063 CT3 0.044

RN100664812 Decordova 8063 CT4 0.044

RN100233998 Bayou Cogeneration Plant 10298 GEN1 0.752

RN100233998 Bayou Cogeneration Plant 10298 GEN2 0.782

RN100233998 Bayou Cogeneration Plant 10298 GEN3 0.757

RN100233998 Bayou Cogeneration Plant 10298 GEN4 0.749

RN100216837 AES Deepwater, Inc. 10670 1001 0.962

RN100239672 Clear Lake Cogeneration 10741 G102 0.984

RN100239672 Clear Lake Cogeneration 10741 G103 0.981

RN100239672 Clear Lake Cogeneration 10741 G104 0.929

RN100216555 Paris Energy Center 50109 HRSG1 0.719

RN100216555 Paris Energy Center 50109 HRSG2 0.686

RN100226554 New Gulf Power Facility 50137 1 0.016

RN100223395 Sweetwater Generation 50615 GT01 0.189

RN100223395 Sweetwater Generation 50615 GT02 0.462

RN100223395 Sweetwater Generation 50615 GT03 0.470
B-127

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN102450756 Exxonmobil Beaumont 50625 61STK1 0.184

RN102450756 Exxonmobil Beaumont 50625 61STK2 0.384

RN102450756 Exxonmobil Beaumont 50625 61STK3 0.351

RN100210863 Altura Channelview C 50815 ENG101 0.757

RN100210863 Altura Channelview C 50815 ENG201 0.765

RN100210863 Altura Channelview C 50815 ENG301 0.560

RN100210863 Altura Channelview C 50815 ENG401 0.571

RN100210863 Altura Channelview C 50815 ENG501 0.558

RN100210863 Altura Channelview C 50815 ENG601 0.762

RN105369805 Sandow Station 52071 5A 0.419

RN105369805 Sandow Station 52071 5B 0.403

RN100224245 Texas City Cogeneration 52088 GT-A 1.044

RN100224245 Texas City Cogeneration 52088 GT-B 1.044

RN100224245 Texas City Cogeneration 52088 GT-C 1.074

RN100215896 C. R. Wing Cogeneration 52176 1 0.678

RN100215896 C. R. Wing Cogeneration 52176 2 0.678

RN100223312 Johnson County Gener 54817 EAST 1.405

RN100217033 Sweeny Cogeneration 55015 1 1.186

RN100217033 Sweeny Cogeneration 55015 2 1.233

RN100217033 Sweeny Cogeneration 55015 3 1.219

RN100217033 Sweeny Cogeneration 55015 4 1.265

RN100222041 Pasadena Power Plant 55047 CG-1 1.323

RN100222041 Pasadena Power Plant 55047 CG-2 1.115

RN100222041 Pasadena Power Plant 55047 CG-3 1.025

RN100245539 Tenaska Frontier Gen 55062 1 1.156

RN100245539 Tenaska Frontier Gen 55062 2 1.170

RN100245539 Tenaska Frontier Gen 55062 3 1.011

RN100217298 Blackhawk Station 55064 1 1.181

RN100217298 Blackhawk Station 55064 2 1.183

RN101286433 Mustang Station 55065 1 1.224

RN101286433 Mustang Station 55065 2 1.186

RN102547957 Gregory Power Facility 55086 101 1.692

RN102547957 Gregory Power Facility 55086 102 1.703

RN102596400 Midlothian Energy 55091 STK1 0.588

RN102596400 Midlothian Energy 55091 STK2 0.708

RN102596400 Midlothian Energy 55091 STK3 0.645

RN102596400 Midlothian Energy 55091 STK4 0.732

RN102596400 Midlothian Energy 55091 STK5 0.112

RN102596400 Midlothian Energy 55091 STK6 0.110

RN100218882 Lamar Power (Paris) 55097 1 0.877

RN100218882 Lamar Power (Paris) 55097 2 0.921

RN100218882 Lamar Power (Paris) 55097 3 0.872
B-128

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100218882 Lamar Power (Paris) 55097 4 0.872

RN102344645 Frontera Generation 55098 1 0.588

RN102344645 Frontera Generation 55098 2 0.585

RN100209766 Sabine Cogeneration 55104 SAB-1 0.445

RN100209766 Sabine Cogeneration 55104 SAB-2 0.445

RN101986818

SRW Cogen Limited 

Partner 55120 CTG-1 0.170

RN101986818

SRW Cogen Limited 

Partner 55120 CTG-2 0.233

RN100209576 Magic Valley Generation 55123 CTG-1 0.468

RN100209576 Magic Valley Generation 55123 CTG-2 0.501

RN101514214 Tenaska Gateway Gen 55132 OGTDB1 0.271

RN101514214 Tenaska Gateway Gen 55132 OGTDB2 0.299

RN101514214 Tenaska Gateway Gen 55132 OGTDB3 0.266

RN100218742 Rio Nogales Power Project 55137 CTG-1 0.211

RN100218742 Rio Nogales Power Project 55137 CTG-2 0.219

RN100218742 Rio Nogales Power Project 55137 CTG-3 0.233

RN100219195 Wolf Hollow I, LP 55139 CTG1 0.652

RN100219195 Wolf Hollow I, LP 55139 CTG2 0.532

RN100211689 Hays Energy Project 55144 STK1 0.107

RN100211689 Hays Energy Project 55144 STK2 0.118

RN100211689 Hays Energy Project 55144 STK3 0.132

RN100211689 Hays Energy Project 55144 STK4 0.159

RN100225820 Guadalupe Generating 55153 CTG-1 0.899

RN100225820 Guadalupe Generating 55153 CTG-2 0.784

RN100225820 Guadalupe Generating 55153 CTG-3 0.455

RN100225820 Guadalupe Generating 55153 CTG-4 0.427

RN100723915 Lost Pines 1 55154 1 0.274

RN100723915 Lost Pines 2 55154 2 0.271

RN101056851 Bastrop Clean Energy 55168 CTG-1A 0.416

RN101056851 Bastrop Clean Energy 55168 CTG-1B 0.458

RN100226232 Bosque County Power 55172 GT-1 0.191

RN100226232 Bosque County Power 55172 GT-2 0.167

RN100226232 Bosque County Power 55172 GT-3 0.353

RN100542695 Eastman Cogeneration 55176 1 0.375

RN100542695 Eastman Cogeneration 55176 2 0.392

RN100220276

Channelview 

Cogeneration 55187 CHV1 0.211

RN100220276

Channelview 

Cogeneration 55187 CHV2 0.189

RN100220276

Channelview 

Cogeneration 55187 CHV3 0.181
B-129

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100220276

Channelview 

Cogeneration 55187 CHV4 0.225

RN100224302 Corpus Christi Energy 55206 CU1 0.540

RN100224302 Corpus Christi Energy 55206 CU2 0.592

RN100223882 Odessa-Ector Generation 55215 GT1 0.321

RN100223882 Odessa-Ector Generation 55215 GT2 0.471

RN100223882 Odessa-Ector Generation 55215 GT3 0.466

RN100223882 Odessa-Ector Generation 55215 GT4 0.540

RN100212430 Ennis Power Company, 55223 GT-1 0.386

RN102333853

Freestone Power 

Generation 55226 GT1 0.370

RN102333853

Freestone Power 

Generation 55226 GT2 0.386

RN102333853

Freestone Power 

Generation 55226 GT3 0.307

RN102333853

Freestone Power 

Generation 55226 GT4 0.334

RN100221985 Jack County Generation 55230 CT-1 0.252

RN100221985 Jack County Generation 55230 CT-2 0.266

RN100668052 Channel Energy Center 55299 CTG1 0.230

RN100668052 Channel Energy Center 55299 CTG2 0.236

RN102584844 Wise County Power Co 55320 GT-1 0.353

RN102584844 Wise County Power Co 55320 GT-2 0.367

RN102326204 Baytown Energy Center 55327 CTG-1 0.271

RN102326204 Baytown Energy Center 55327 CTG-2 0.195

RN102326204 Baytown Energy Center 55327 CTG-3 0.203

RN100216092 Brazos Valley Energy 55357 CTG1 0.175

RN100216092 Brazos Valley Energy 55357 CTG2 0.159

RN400226109

Cottonwood Energy 

Project 55358 CT1 0.153

RN400226109

Cottonwood Energy 

Project 55358 CT2 0.142

RN400226109

Cottonwood Energy 

Project 55358 CT3 0.162

RN400226109

Cottonwood Energy 

Project 55358 CT4 0.184

RN102041282 Exelon Laporte Gener 55365 GT-1 0.005

RN102041282 Exelon Laporte Gener 55365 GT-2 0.005

RN102041282 Exelon Laporte Gener 55365 GT-3 0.003

RN102041282 Exelon Laporte Gener 55365 GT-4 0.003

RN100222033 Deer Park Energy Center 55464 CTG1 0.178

RN100222033 Deer Park Energy Center 55464 CTG2 0.153
B-130

TCEQ Regulated 

Entity Number CAMD Facility Name

CAMD 

ORISPL 

ID

CAMD 

UNIT ID

CAIR 

Allocation 

from General 

Pool, tpd

CAIR 

Allocation 

from New 

Pool, tpd

RN100222033 Deer Park Energy Center 55464 CTG3 0.159

RN100222033 Deer Park Energy Center 55464 CTG4 0.145

RN103934493 South Houston Green 55470 EPN801 0.238

RN103934493 South Houston Green 55470 EPN802 0.252

RN103934493 South Houston Green 55470 EPN803 0.249

RN100213420 FPLE Forney, LP 55480 U1 0.389

RN100213420 FPLE Forney, LP 55480 U2 0.334

RN100213420 FPLE Forney, LP 55480 U3 0.345

RN100213420 FPLE Forney, LP 55480 U4 0.452

RN100213420 FPLE Forney, LP 55480 U5 0.499

RN100213420 FPLE Forney, LP 55480 U6 0.458

RN101061927 Harrison County Power 55664 GT-1 0.041

RN101061927 Harrison County Power 55664 GT-2 0.077

RN104333521 Mustang Station Unit 56326 GEN1 0.025

RN104333521 Mustang Station Unit 56326 GEN2 0.005

RN104763099 Quail Run Energy Center 56349 CT1A 0.063

RN104763099 Quail Run Energy Center 56349 CT1B 0.055

RN104763099 Quail Run Energy Center 56349 CT2A 0.063

RN104763099 Quail Run Energy Center 56349 CT2B 0.052

RN104772538 Colorado Bend Energy 56350 CT1A 0.066

RN104772538 Colorado Bend Energy 56350 CT1B 0.052

RN104772538 Colorado Bend Energy 56350 CT2A 0.093

RN104772538 Colorado Bend Energy 56350 CT2B 0.096

RN105295927 San Jacinto County P 56603 SJCCT1 0.005

RN105295927 San Jacinto County P 56603 SJCCT2 0.008

RN105295802 Hardin County Peaking 56604 HCCT1 0.011

RN105295802 Hardin County Peaking 56604 HCCT2 0.003

RN105377352

Winchester Power 

Partners 56674 1 0.003

RN105377352

Winchester Power 

Partners 56674 2 0.005

RN105377352

Winchester Power 

Partners 56674 3 0.003

RN105377352

Winchester Power 

Partners 56674 4 0.005

New Pool CAIR 

Allocation available for new facilities 1.126
B-131

ATTACHMENT2: ON-ROAD MOBILE SOURCE MODELING 

EMISSIONS DEVELOPMENT WITH MOBILE6.2

ON-ROAD MOBILE SOURCE EMISSIONS INVENTORIES FOR NINE-COUNTY 

DFW AREA

The purpose of this section is to provide a brief overview of the nine-county DFW area on-road 

mobile source emissions inventory files that were input into the photochemical model for the 

2006 base case, the 2006 baseline case, and the 2012 future case used in the proposed DFW SIP 

revision. These inventory data sets were developed under contract by the North Central Texas 

Council of Governments (NCTCOG) based on travel demand model output for the DFW area. 

For each of the nine DFW counties, NCTCOG combined MOBILE6.2 emissions rate output with 

vehicle miles traveled (VMT) estimates from the local travel demand model. The net result is 

referred to as a link-based inventory because both hourly VMT and emissions estimates are 

developed for each roadway segment or link in the network. For each year, summer season onroad emission inventories were developed for the five day types of weekday (i.e., TuesdayThursday average), Friday, Saturday, Sunday, and Monday. Since these days types are based on 

a summer season, development of separate baseline OSD emissions were not needed. For the 

on-road category, base case and baseline emissions are the same.

Table 64, Att. 2: VMT, NOX, VOC, and CO Summary for 2006 DFW On-Road Inventory and 

Table 65, Att. 2: VMT, NOX, VOC, and CO Summary for 2012 DFW On-Road Inventory provide 

summaries of the total VMT, NOX, VOC, and CO emissions for the entire nine-county DFW area 

for each day type for the 2006 case and 2012 future case, respectively. As shown, Fridays have 

the highest total VMT of the week, while Saturdays and Sundays have the lowest total daily 

VMT. While overall VMT increases with future growth, total emissions decrease from 2006 to 

2012 as a result of more stringent emissions standards for newer vehicles entering the fleet, 

combined with the simultaneous attrition of older, higher-emitting vehicles. Consistent with 

current federal and state rules, the on-road inventories from NCTCOG include the benefits of:

• reformulated gasoline (RFG) in Collin, Dallas, Denton, and Tarrant Counties;

• low Reid vapor pressure (RVP) gasoline in Ellis, Johnson, Kaufman, Parker, and Rockwall 

Counties;

• the inspection and maintenance (I/M) Program in all nine counties; and

• Texas low emission diesel (TxLED) fuel for all nine counties.

Table 64, Att. 2: VMT, NOX, VOC, and CO Summary for 2006 DFW On-Road 

Inventory

Day

Type

Vehicle Miles 

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Weekday 154,154,062 226.90 105.04 1,234.98

Friday 169,104,545 235.09 115.61 1,358.91

Saturday 136,580,382 162.03 96.19 1,150.26

Sunday 111,703,992 138.00 80.16 958.93

Monday 148,647,961 221.01 100.78 1,198.70
B-132

Table 65, Att. 2: VMT, NOX, VOC, and CO Summary for 2012 DFW On-Road 

Inventory

Day

Type

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Weekday 188,134,364 123.13 79.85 986.17

Friday 209,263,216 130.94 89.48 1,098.21

Saturday 171,997,564 97.58 75.83 946.73

Sunday 141,782,290 82.97 63.50 793.48

Monday 188,108,918 123.26 79.62 987.82

Even though all of the day type on-road inventory data sets were used for photochemical model 

input, only the summer weekday emissions will be detailed here. For the 2006 base case and 

2012 future case, Table 66, Att. 2: Summary of 2006 DFW Summer Weekday On-Road 

Inventory by County and Table 67, Att. 2: Summary of 2012 DFW Summer Weekday On-Road 

Inventory by County present respective summaries of the VMT, NOX, VOC, and CO emissions 

for each of the nine counties in the DFW area.

Table 66, Att. 2: Summary of 2006 DFW Summer Weekday On-Road Inventory by 

County

DFW Area

County

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 16,068,710 19.36 9.50 116.53

Dallas 64,281,838 84.40 46.21 527.59

Denton 13,408,318 18.95 8.03 98.25

Ellis 5,298,407 14.93 3.58 44.37

Johnson 4,345,589 9.05 3.45 39.43

Kaufman 4,533,347 12.08 3.17 39.66

Parker 3,796,119 10.26 2.70 33.13

Rockwall 1,926,972 5.11 1.22 15.03

Tarrant 40,494,762 52.77 27.17 320.99

Total 154,154,062 226.90 105.04 1,234.98

Table 67, Att. 2: Summary of 2012 DFW Summer Weekday On-Road Inventory by 

County

DFW Area

County

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 20,189,452 10.64 7.32 97.63

Dallas 75,484,002 47.43 33.95 410.42

Denton 18,516,332 10.38 6.82 89.32

Ellis 7,237,704 7.61 3.11 38.44

Johnson 5,343,688 4.72 2.66 30.55

Kaufman 5,632,724 5.77 2.52 31.41

Parker 4,663,328 4.92 2.04 25.21
B-133

DFW Area

County

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Rockwall 2,321,347 2.22 0.92 11.45

Tarrant 48,745,787 29.44 20.52 251.75

Total 188,134,364 123.13 79.85 986.17

Table 68, Att. 2: Summary of 2006 DFW Summer Weekday On-Road Inventory by Vehicle 

Type and Table 69, Att. 2: Summary of 2012 DFW Summer Weekday On-Road Inventory by 

Vehicle Type present respective summaries for 2006 and 2012 of the VMT, NOX, VOC, and CO 

emissions for each of the 28 vehicle classes in MOBILE6.2.

Table 68, Att. 2: Summary of 2006 DFW Summer Weekday On-Road Inventory by 

Vehicle Type

MOBILE6.2 

Vehicle Category

Vehicle

Miles Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

LDGV 103,439,304 65.74 69.06 805.46

LDGT1 6,767,949 4.92 5.63 66.77

LDGT2 22,530,425 23.35 19.57 243.84

LDGT3 6,579,826 5.83 3.30 54.37

LDGT4 3,025,868 3.83 1.66 25.82

HDGV2b 1,005,286 3.36 0.46 6.08

HDGV3 288,283 1.33 0.26 2.81

HDGV4 145,049 0.72 0.16 1.29

HDGV5 79,791 0.57 0.25 2.12

HDGV6 136,526 0.73 0.20 1.90

HDGV7 34,277 0.23 0.06 0.52

HDGV8a 34,410 0.27 0.08 0.83

HDGV8b 4,688 0.04 0.01 0.09

LDDV 119,035 0.13 0.06 0.17

LDDT12 67,925 0.18 0.19 0.33

HDDV2b 1,256,044 3.92 0.18 1.02

HDDV3 337,857 1.28 0.06 0.32

HDDV4 239,324 1.14 0.06 0.27

HDDV5 161,645 0.83 0.04 0.20

HDDV6 519,480 3.62 0.18 0.66

HDDV7 188,968 1.72 0.09 0.31

HDDV8a 325,046 4.87 0.16 0.86

HDDV8b 5,634,984 92.36 2.31 12.95

MC 110,268 0.14 0.31 1.50

HDGB 44,298 0.41 0.21 3.01

HDDBT 146,971 2.39 0.06 0.53

HDDBS 208,046 2.33 0.14 0.48

LDDT34 722,489 0.66 0.28 0.48
B-134

MOBILE6.2 

Vehicle Category

Vehicle

Miles Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Total 154,154,062 226.90 105.04 1,234.98

Table 69, Att. 2: Summary of 2012 DFW Summer Weekday On-Road Inventory by 

Vehicle Type

MOBILE6.2

Vehicle Category

Vehicle Miles

Traveled

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

LDGV 128,270,065 43.13 50.51 649.51

LDGT1 7,296,632 3.57 4.49 50.39

LDGT2 24,292,930 17.24 15.86 189.97

LDGT3 9,387,705 4.35 3.02 50.39

LDGT4 4,316,079 2.93 1.53 24.16

HDGV2b 1,187,278 1.07 0.24 5.40

HDGV3 295,583 0.46 0.10 1.66

HDGV4 164,343 0.28 0.07 0.90

HDGV5 60,140 0.27 0.12 0.45

HDGV6 113,261 0.42 0.13 0.79

HDGV7 24,833 0.12 0.03 0.19

HDGV8a 25,882 0.16 0.05 0.23

HDGV8b 2,506 0.01 0.00 0.03

LDDV 112,780 0.03 0.01 0.08

LDDT12 225 0.00 0.00 0.00

HDDV2b 1,779,557 2.73 0.19 0.55

HDDV3 475,441 0.87 0.06 0.19

HDDV4 336,252 0.82 0.06 0.19

HDDV5 223,885 0.56 0.04 0.11

HDDV6 718,053 2.02 0.16 0.36

HDDV7 215,397 0.94 0.07 0.17

HDDV8a 365,728 2.42 0.12 0.46

HDDV8b 7,071,910 33.56 2.18 6.64

MC 132,265 0.13 0.37 1.89

HDGB 31,197 0.24 0.06 0.35

HDDBT 208,413 2.07 0.05 0.38

HDDBS 319,109 2.48 0.17 0.46

LDDT34 706,916 0.24 0.15 0.29

Total 188,134,364 123.13 79.85 986.17

The MOBILE6.2 input files used to develop these inventories, along with detailed reports and 

tab-delimited summary output data, can be found on the following FTP sites for 2006 and 2012, 

respectively:
B-135

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/m62/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/m62/2012/

On-Road Mobile Source Emission Adjustments and Controls

The on-road emissions inventory data provided by NCTCOG were prepared for input into the 

photochemical model using EPS3. When input into EPS3, the inventory data are in a readable 

text-based format. However, once within EPS3, the emissions data are maintained in a binary 

format. Table 70, Att. 2: EPS3 Modules Used to Process Nine-County DFW On-Road Emissions 

Data summarizes the EPS3 modules that were used to process the nine-county DFW on-road 

inventories.

Table 70, Att. 2: EPS3 Modules Used to Process Nine-County DFW On-Road 

Emissions Data

EPS3

Module Description

LBASE Spatially allocate link-based emissions among grid cells.

PREAM Prepare non-link “roadway type” emissions for further processing.

PREPNT Prepare stationary extended idling emissions for further processing.

CNTLEM Apply controls to model strategies, apply adjustments, etc.

TMPRL Apply temporal profiles to extended idling emissions.

CHMSPL Chemically speciate emissions into NO, NO2, olefins, parrafins, etc.

GRDEM Sum emissions by grid cell for photochemical model input.

MRGUAM Merge and adjust multiple gridded files for photochemical model input.

The EPS3 CNTLEM module was used to:

• remove 3.4% of the HDDV8a and HDDV8b (eighteen-wheeler) emissions for separate 

processing as extended idling emissions in accordance with the January 2004 EPA Guidance 

for Quantifying and Using Long Duration Truck Idling Emission Reductions in State 

Implementation Plans and Transportation Conformity; and

• apply a temperature/humidity NOX correction to both diesel and heavy-duty gasoline 

vehicles.

EPA issued a document in January 2004 entitled Guidance for Quantifying and Using Long 

Duration Truck Idling Emission Reductions in State Implementation Plans and 

Transportation Conformity. This EPA guidance states that extended idling emissions account 

for 3.4% of the total emissions calculated with MOBILE6.2 for the HDDV8a and HDDV8b 

vehicle classes. As shown above, the CNTLEM module was used to remove 3.4% of the hourly 

NOX, VOC, and CO emissions from the running emissions prepared for photochemical model 

input from the HDDV8a and HDDV8b classes. Using a combination of SAS and LINUX code, 

these extended idling emissions were aggregated into a nine-county 24-hour total and spatially 

assigned to known truck stop locations. The extended idling emissions were then processed 

through EPS3 as if they were stationary low-level point sources. The emissions were temporally 

allocated as the inverse of HDDV8a/HDDV8b hourly VMT. Consequently, more of the extended 

idling emissions were allocated during overnight hours rather than daytime hours. The extended 

idling emissions were also run through the CNTLEM module to receive a temperature/humidity 

NOX correction. The summer weekday extended idling emissions by county are presented below 

in Table 71, Att. 2: 2006 HDDV8a and HDDV8b Extended Idling Emissions for Nine-County 
B-136

DFW and Table 72, Att. 2: 2012 HDDV8a and HDDV8b Extended Idling Emissions for NineCounty DFW. Greater detail on heavy-duty vehicle idling activity specific to Texas metropolitan 

areas can be found in reports located on the following web site: 

http://www.tceq.texas.gov/airquality/airmod/project/pj_report_mob.html.

Table 71, Att. 2: 2006 HDDV8a and HDDV8b Extended Idling Emissions for NineCounty DFW

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 0.261 0.007 0.039

Dallas 0.884 0.023 0.129

Denton 0.259 0.007 0.038

Ellis 0.243 0.006 0.036

Johnson 0.021 0.001 0.003

Kaufman 0.500 0.013 0.074

Parker 0.492 0.013 0.071

Rockwall 0.191 0.005 0.028

Tarrant 0.352 0.009 0.052

Total 3.204 0.084 0.470

Table 72, Att. 2: 2012 HDDV8a and HDDV8b Extended Idling Emissions for NineCounty DFW

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 0.097 0.006 0.020

Dallas 0.327 0.022 0.066

Denton 0.096 0.006 0.020

Ellis 0.090 0.006 0.018

Johnson 0.008 0.001 0.002

Kaufman 0.185 0.012 0.038

Parker 0.182 0.012 0.037

Rockwall 0.071 0.005 0.015

Tarrant 0.130 0.009 0.027

Total 1.185 0.078 0.242

The MOBILE6.2 model accounts for the effects that changes in hourly temperature and 

humidity have on NOX emissions for only six of the 28 total vehicle types. These vehicle types 

are the MOBILE6.2 light-duty gasoline vehicle (LDGV), light-duty gasoline trucks 1-4 (LDGT1-

4), and motorcycle (MC) classes. There is no temperature/humidity NOX correction in 

MOBILE6.2 for the remaining 22 vehicle classes, which include all 13 of the diesel-powered 

vehicle classes and the nine heavy-duty gasoline vehicle classes. Under contract to the Houston 

Advanced Research Center (HARC), Environ worked with the Southwest Research Institute 

Temperature/Humidity NOX Correction
B-137

(SwRI) to develop temperature/humidity NOX correction equations to apply to both the 13 

diesel and nine heavy-duty gasoline vehicle classes in MOBILE6.2. These equations reflect the 

fact that as ambient temperature increases, tailpipe NOX emissions increase. However, as 

ambient humidity increases, tailpipe NOX emissions decrease. Greater detail on the 

development of these correction equations can be found in Appendices F.4 and F.5 of the 

December 2004 Houston-Galveston-Brazoria (HGB) SIP revision, which can be found at 

http://www.tceq.texas.gov/implementation/air/sip/dec2004hgb_mcr.html.

The EPS3 CNTLEM module referenced above in Table 70 allows the user to apply a different 

NOX, VOC, and/or CO correction for each hour, episode day, county, and vehicle type 

combination. TCEQ modeling staff developed SAS code to calculate the appropriate NOX

adjustment factors for each county and vehicle type using hourly inputs for temperature, relative 

humidity, and barometric pressure. The hourly temperature, relative humidity, and barometric 

pressure inputs used by the SAS software were also used by NCTCOG in its development of the 

2006 and 2012 on-road inventories. These meteorological data were obtained from National 

Weather Service (NWS) and TCEQ monitors in the DFW area for the time period of May 15-

September 15, 2006. The spreadsheets that were developed to obtain the final hourly inputs are 

available at ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/m62/2006/.

Table 73, Att. 2: Summary of 2006 Temperature/Humidity On-Road NOX Correction and 

Table 11, Att. 2: Table 74, Att. 2: Summary of 2012 Temperature/Humidity On-Road NOX

Correction present the temperature and humidity corrections applied to each day type for the 

2006 base case and 2012 future case, respectively. For each episode day, there are greater NOX

reductions during the overnight and early morning hours when the temperature is at its 

minimum and the relative humidity is at its maximum. However, during the hottest hours of the 

afternoon when the relative humidity is at its lowest, the temperature/humidity correction 

either decreases NOX very slightly or increases it somewhat, depending upon the specific 

conditions for that hour. Overall, the temperature/humidity correction procedure allows not 

only for improved estimates of the total on-road NOX emissions, but also for improved spatial 

and temporal allocation of those emissions.

Table 73, Att. 2: Summary of 2006 Temperature/Humidity On-Road NOX

Correction

Day

Type

Temperature/Humidity

NOX Reduction (tpd)

Weekday 1.59

Friday 1.47

Saturday 0.74

Sunday 0.49

Monday 1.53

Table 74, Att. 2: Summary of 2012 Temperature/Humidity On-Road NOX

Correction

Day

Type

Temperature/Humidity NOX

Reduction (tpd)

Weekday 0.66

Friday 0.61

Saturday 0.32
B-138

Day

Type

Temperature/Humidity NOX

Reduction (tpd)

Sunday 0.21

Monday 0.65

The 2006 and 2012 on-road inventories for the nine-county DFW area include the benefits of 

RFG, low RVP gasoline, and I/M. The summer weekday RFG benefits for 2006 and 2012 are 

provided in 

Reformulated Gasoline Benefits

Table 75, Att.2: Summary of 2006 Summer Weekday RFG Benefits by County and 

Table 76, Att. 2: Summary of 2012 Summer Weekday RFG Benefits by County, respectively.

Table 75, Att.2: Summary of 2006 Summer Weekday RFG Benefits by County

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 0.23 2.07 12.26

Dallas 1.05 10.38 59.00

Denton 0.19 1.79 10.62

Tarrant 0.60 5.94 35.83

Total 2.08 20.18 117.70

Table 76, Att. 2: Summary of 2012 Summer Weekday RFG Benefits by County

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 0.11 1.61 9.72

Dallas 0.58 7.46 41.76

Denton 0.10 1.52 9.06

Tarrant 0.32 4.43 25.27

Total 1.12 15.02 85.82

The summer weekday low RVP gasoline benefits for 2006 and 2012 are provided in 

Low Reid Vapor Pressure Gasoline Benefits

Table 77, 

Att. 2: Summary of 2006 Summer Weekday Low RVP Gasoline Benefits by County and Table 

78, Att. 2: Summary of 2012 Summer Weekday Low RVP Gasoline Benefits by County, 

respectively.
B-139

Table 77, Att. 2: Summary of 2006 Summer Weekday Low RVP Gasoline Benefits 

by County

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Ellis 0.04 0.28 0.97

Johnson 0.03 0.29 0.89

Kaufman 0.03 0.25 0.92

Parker 0.03 0.21 0.70

Rockwall 0.01 0.10 0.33

Total 0.14 1.13 3.80

Table 78, Att. 2: Summary of 2012 Summer Weekday Low RVP Gasoline Benefits 

by County

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Ellis 0.04 0.23 0.83

Johnson 0.03 0.21 0.66

Kaufman 0.03 0.19 0.72

Parker 0.02 0.15 0.52

Rockwall 0.01 0.07 0.25

Total 0.13 0.86 2.98

The summer weekday I/M program benefits for 2006 and 2012 are provided in 

Inspection/Maintenance Program Benefits

Table 79, Att. 2: 

Summary of 2006 Summer Weekday I/M Program Benefits by County and Table 80, Att. 2: 

Summary of 2012 Summer Weekday I/M Program Benefits by County, respectively.

Table 79, Att. 2: Summary of 2006 Summer Weekday I/M Program Benefits by 

County

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 1.72 1.44 25.13

Dallas 7.97 6.77 115.71

Denton 1.43 1.20 21.01

Ellis 0.57 0.53 10.03

Johnson 0.54 0.53 9.36

Kaufman 0.50 0.47 8.94

Parker 0.43 0.41 7.65

Rockwall 0.20 0.19 3.43

Tarrant 4.73 4.00 69.62

Total 18.09 15.52 270.87
B-140

Table 80, Att. 2: Summary of 2012 Summer Weekday I/M Program Benefits by 

County

DFW Area

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 2.37 1.71 31.92

Dallas 10.12 7.50 133.72

Denton 2.17 1.57 28.93

Ellis 0.83 0.68 13.19

Johnson 0.70 0.59 10.88

Kaufman 0.67 0.55 10.85

Parker 0.55 0.44 8.75

Rockwall 0.26 0.21 4.07

Tarrant 6.05 4.45 80.61

Total 23.72 17.70 322.91

Based on an EPA memorandum entitled Texas Low Emission Diesel (LED) Fuel Benefits, 

September 27, 2001, a 4.8% NOX TxLED benefit should be claimed for 2002-and-newer diesel 

vehicles and a 6.2% NOX TxLED benefit should be claimed for 2001-and-older diesel vehicles. In 

order to determine the specific TxLED adjustment factors that should apply to each of the 13 

diesel vehicle types, MOBILE6.2 runs were performed for the DFW area to determine NOX

emissions rates by model year. By using these data, the 4.8% and 6.2% reduction factors were 

weighted according to NOX emission model year contributions for each vehicle type. The 

resulting TxLED adjustment factors and benefits for both 2006 and 2012 are summarized in 

Texas Low Emission Diesel Fuel Benefits

Table 81, Att. 2: Summary of 2006 Summer Weekday TxLED Benefits by Vehicle Type and

Table 82, Att. 2: Summary of 2012 Summer Weekday TxLED Benefits by Vehicle Type, 

respectively. The TxLED adjustment factors were incorporated by NCTCOG into the on-road 

inventories by post-processing the MOBILE6.2 diesel NOX emission rates.

Table 81, Att. 2: Summary of 2006 Summer Weekday TxLED Benefits by Vehicle 

Type

Diesel

Vehicle Type

NOX

Reduction

Adjustment

Factor

NOX Benefit

(tpd)

LDDV 6.14% 0.9386 0.008

LDDT12 6.20% 0.9380 0.012

HDDV2b 5.11% 0.9489 0.209

HDDV3 5.42% 0.9458 0.072

HDDV4 5.66% 0.9434 0.068

HDDV5 5.59% 0.9441 0.049

HDDV6 5.66% 0.9434 0.215

HDDV7 5.73% 0.9427 0.103

HDDV8a 5.92% 0.9408 0.302

HDDV8b 5.84% 0.9416 5.661

HDDBT 5.87% 0.9413 0.147
B-141

Diesel

Vehicle Type

NOX

Reduction

Adjustment

Factor

NOX Benefit

(tpd)

HDDBS 5.87% 0.9413 0.143

LDDT34 5.56% 0.9444 0.039

Total 7.028

Table 82, Att. 2: Summary of 2012 Summer Weekday TxLED Benefits by Vehicle 

Type

Diesel

Vehicle Type

NOX

Reduction

Adjustment

Factor

NOX Benefit

(tpd)

LDDV 5.81% 0.9419 0.002

LDDT12 6.20% 0.9380 0.000

HDDV2b 4.97% 0.9503 0.141

HDDV3 5.04% 0.9496 0.046

HDDV4 5.30% 0.9470 0.046

HDDV5 5.30% 0.9470 0.031

HDDV6 5.26% 0.9474 0.111

HDDV7 5.35% 0.9465 0.053

HDDV8a 5.60% 0.9440 0.142

HDDV8b 5.13% 0.9487 1.793

HDDBT 5.54% 0.9446 0.120

HDDBS 5.75% 0.9425 0.149

LDDT34 5.20% 0.9480 0.013

Total 2.647

The on-road control strategy benefits referenced above are summarized below in 

On-Road Control Strategy Benefits Summary

Table 83, Att. 

2: Summary of 2006 Summer Weekday On-Road Control Strategy Benefits and Table 84, Att. 

2: Summary of 2012 Summer Weekday On-Road Control Strategy Benefits. When determining 

the amount of benefit assigned to specific on-road control strategies, the sequence in which they 

are modeled with MOBILE6.2 is important. For example, the RFG benefit for each county was 

determined by calculating the difference between a MOBILE6.2 run with conventional gasoline 

and a run with RFG. For both runs, the I/M program was not modeled and all other inputs were 

held constant. Then, the I/M program benefits were determined by calculating the difference 

between a MOBILE6.2 run with RFG and a run with both RFG and I/M. If the benefits were 

calculated in a different order, the benefit assigned to each individual strategy would vary, but 

the magnitude of the combined benefits would not change. Since RFG and I/M affect gasolinepowered vehicles only, it does not matter where in the sequence TxLED is modeled because it 

only affects diesel-powered vehicles.
B-142

Table 83, Att. 2: Summary of 2006 Summer Weekday On-Road Control Strategy 

Benefits

Control

Strategy

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

RFG 2.08 20.18 117.70

Low RVP 0.14 1.13 3.80

I/M 18.09 15.52 270.87

TxLED 7.03

Total 27.34 36.83 392.38

Table 84, Att. 2: Summary of 2012 Summer Weekday On-Road Control Strategy 

Benefits

Control

Strategy

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

RFG 1.12 15.02 85.82

Low RVP 0.13 0.86 2.98

I/M 23.72 17.70 322.91

TxLED 2.65

Total 27.61 33.59 411.70

Nine-County DFW Photochemical Modeling Input

The summer weekday on-road emissions by county that were input into the photochemical 

model are summarized below in Table 85, Att. 2: 2006 Summer Weekday On-Road Mobile 

Source Inventory by County and Table 86, Att. 2: 2012 Summer Weekday On-Road Mobile 

Source Inventory by County. The on-road inventory summaries in Table 85 and Table 86 are a 

combination of both running and extended idling emissions. In addition, the 

temperature/humidity NOX correction has been applied as summarized above.

Table 85, Att. 2: 2006 Summer Weekday On-Road Mobile Source Inventory by 

County

DFW Area 

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 19.19 9.50 116.53

Dallas 83.96 46.21 527.59

Denton 18.81 8.03 98.25

Ellis 14.69 3.58 44.37

Johnson 8.83 3.45 39.43

Kaufman 12.09 3.17 39.66

Parker 10.50 2.70 33.13

Rockwall 5.12 1.22 15.03

Tarrant 52.14 27.17 320.99

Total 225.31 105.04 1,234.98
B-143

Table 86, Att. 2: 2012 Summer Weekday On-Road Mobile Source Inventory by 

County

DFW Area 

County

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Collin 10.58 7.32 97.63

Dallas 47.25 33.95 410.42

Denton 10.34 6.82 89.32

Ellis 7.50 3.11 38.44

Johnson 4.63 2.66 30.55

Kaufman 5.77 2.52 31.41

Parker 5.00 2.04 25.21

Rockwall 2.22 0.92 11.45

Tarrant 29.19 20.52 251.75

Total 122.47 79.85 986.17

The total nine-county DFW on-road emissions input to the photochemical model by day type are 

summarized below in Table 87, Att. 2: 2006 On-Road Mobile Source Inventory by Day Type

and Table 88, Att. 2: 2012 On-Road Mobile Source Inventory by Day Type.

Table 87, Att. 2: 2006 On-Road Mobile Source Inventory by Day Type

Day

Type

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Weekday 225.31 105.04 1,234.98

Friday 234.03 116.54 1,366.64

Saturday 161.41 96.27 1,150.89

Sunday 136.81 78.84 948.06

Monday 219.36 100.67 1,197.91

Table 88, Att. 2: 2012 On-Road Mobile Source Inventory by Day Type

Day

Type

NOX

(tpd)

VOC

(tpd)

CO

(tpd)

Weekday 122.47 79.85 986.17

Friday 130.79 90.22 1,105.69

Saturday 97.28 75.77 946.95

Sunday 82.12 62.31 783.62

Monday 122.57 79.48 987.47

For the on-road mobile inventory portion of the DFW subdomain, the EPS3 message files along 

with the gridded files input into the photochemical model for 2006 and 2012 are available on 

the following FTP sites, respectively:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/eps3/2006/
B-144

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/eps3/2012/

Similar on-road mobile EPS3 message and gridded files for the Texas-only portion of the larger 

12 km modeling domain are available for 2006 and 2012, respectively, on the following FTP 

sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/eps3/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/eps3/2012/

Similar on-road mobile EPS3 message and gridded files for both the Texas and non-Texas 

portions of the larger 12 km modeling domain are available for 2006 and 2012, respectively, on 

the following FTP sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/US/eps3/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/US/eps3/2012/

Attainment Demonstration Motor Vehicle Emissions Budget

By definition, the future case on-road emissions inventory input into the final attainment 

demonstration photochemical modeling run should establish the motor vehicle emissions 

budget (MVEB). However, use of the EPS3 processor introduces unique adjustments to the onroad emissions inventory that are necessary for photochemical modeling efforts. An EPS3 

processing step necessary for photochemical model input involves the use of Central Standard 

Time (CST) instead of Central Daylight Time (CDT). All photochemical modeling inventory files 

must be in CST to be consistent with the way meteorological data are reported and modeled. 

However, emissions inventory files are typically developed in CDT.

When governmental organizations need to demonstrate conformity to the MVEB, they will not 

be developing photochemical modeling inventories and therefore will not apply this time-shift 

step. Consequently, the 2012 MVEB for the nine-county DFW area will start with the summer 

weekday on-road inventory as received from NCTCOG in CDT format. Then, adjustments for the 

temperature/humidity NOX correction are applied outside of EPS3, but in a manner consistent 

with the descriptions included above. This approach is summarized below in Table 89, Att. 2: 

2012 Attainment Demonstration MVEB for the Nine-County DFW Area.

Table 89, Att. 2: 2012 Attainment Demonstration MVEB for the Nine-County DFW 

Area

Nine-County DFW Area

On-Road Emissions

NOX

(tpd)

VOC

(tpd)

2012 On-Road Inventory From NCTCOG (Table 28)

Includes RFG, Low RVP, I/M, and TxLED 123.13 79.85

2012 Temperature/Humidity NOX Correction 0.66

2012 Nine-County DFW Attainment Demonstration

Motor Vehicle Emissions Budget 122.47 79.85

The following pages contain graphical plots of the 2006 and 2012 on-road summer weekday 

NOX and VOC emissions for the greater DFW area. These plots are respectively entitled 

• Figure 47, Att. 2: 2006 DFW Summer Weekday NOX Emissions, 

• Figure 48, Att. 2: 2006 DFW Summer Weekday VOC Emissions, 
B-145

• Figure 49, Att. 2: 2012 DFW Summer Weekday NOX Emissions, and 

• Figure 50, Att. 2: 2012 DFW Summer Weekday VOC Emissions.
B-146

Figure 47, Att. 2: 2006 DFW Summer Weekday NOX Emissions
B-147

Figure 48, Att. 2: 2006 DFW Summer Weekday VOC Emissions
B-148

Figure 49, Att. 2: 2012 DFW Summer Weekday NOX Emissions
B-149

Figure 50, Att. 2: 2012 DFW Summer Weekday VOC Emissions
B-150

On-Road Mobile Source Emissions Inventories for Non-DFW Areas

On-road emission inventories for 2006 and 2012 were also developed for portions of the 

modeling domain outside of the nine-county DFW area. For the three counties of Hood, Hunt, 

and Wise, a similar link-based inventory development approach was taken by NCTCOG based 

on local travel demand model output. Similar to the nine-county DFW area, on-road emissions 

were developed for the five day types of weekday, Friday, Saturday, Sunday, and Monday. More 

detail on the development of these Hood, Hunt, and Wise inventories is available on the 

following FTP sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/m62/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/DFW/m62/2012/

For the Texas counties outside of the DFW area, on-road emissions were developed by the Texas 

Transportation Institute (TTI) using Highway Performance Monitoring System (HPMS) data as 

the basis for VMT estimates. Summer season emission estimates were developed for the four 

day types of weekday, Friday, Saturday, and Sunday. Hourly emission rates from MOBILE6.2 

were coupled with county-level VMT estimates by roadway type for 2006 and 2012. More detail 

on the development of these HPMS-based on-road inventories is available on the following FTP 

sites:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/eps3/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/Statewide/eps3/2012/

On-road emission estimates for non-Texas states within the photochemical modeling domain 

were developed for 2006 and 2012 using the EPA National Mobile Inventory Model (NMIM), 

which is available at http://www.epa.gov/otaq/nmim.htm and can be used to develop on-road 

county-level emission estimates for every year from 1999-2050. However, the NMIM activity 

database is only populated with county-level VMT figures for 1999 and 2002. Historical annual 

VMT figures by state from 1980-2006 were obtained from the Federal Highway Administration 

(FHWA) Highway Statistics Series webpage, which is available at 

http://www.fhwa.dot.gov/policy/ohpi/hss/index.cfm. Linear trends were established with these 

data to project 2012 VMT for each state and roadway type. NMIM was run for 2006 and 2012 

for all non-Texas states after inclusion of these FHWA-based VMT figures into the NMIM 

activity tables, and the results are available at:

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/US/eps3/2006/

• ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/US/eps3/2012/

Since only average weekday emissions can easily be obtained with NMIM, Friday, Saturday, and 

Sunday day type emissions were estimated for the non-Texas area by applying adjustment 

factors with the EPS3 TMPRL module. These adjustment factors were based on the ratios of 

Friday/weekday, Saturday/weekday, and Sunday/weekday emissions from the statewide 

inventories developed by NCTCOG and TTI for Texas. More detail on this approach is 

documented in a report entitled Use of the National Mobile Inventory Model for Photochemical 

Modeling Applications in Texas, which was presented at the 17th International Emissions 

Inventory Conference and is available at ftp://amdaftp.tceq.texas.gov/pub/Mobile_EI/NMIM/. 

A summary of the different emission estimation approaches taken for this DFW SIP revision is 

provided in Table 90, Att. 2: On-Road Inventory Development by Area within the Modeling 

Domain.
B-151

Table 90, Att. 2: On-Road Inventory Development by Area within the Modeling 

Domain

On-Road Inventory

Development Parameter

Texas

Metropolitan Areas

Texas

Rural Areas

Non-Texas

States and Counties

VMT

Source

Travel Demand

Models (TDMs)

HPMS

Data Sets

NMIM Database /

FHWA Statistics

VMT

Resolution

Roadway Links

From TDM

19 Roadway

Types

12 Roadway

Types

Season

Types

School and Summer

(i.e., non-School)

Summer

Only

Summer

Only

Day

Types

Weekday, Friday,

Saturday, and Sunday

Weekday, Friday,

Saturday, and Sunday

Weekday, Friday,

Saturday, and Sunday

Hourly

VMT? Yes Yes No

VMT Mix Variation by

Day/Time Period Yes Yes No

Roadway Speed

Distribution

Varies by Hour

and Link

Varies by Hour and

Roadway Type

MOBILE6.2

Default

Spatial

Resolution Excellent Very

Good Good

Temporal

Resolution Excellent Very

Good Good

Number of MOBILE6.2

Vehicle Types 28 28 12

Temperature/Humidity

Diesel NOX Correction Yes Yes No

"Eighteen-Wheeler" Idling

Emissions Separation Yes No No
B-152

ATTACHMENT 3: ALTERNATIVE POINT SOURCE GROWTH 

MODELING SENSITIVITY

A 2012 modeling sensitivity was completed using the ERC registry of 0.9 tpd and the DERC flow 

control limit of 5.93 tpd instead of the TIPI-REMI-EGAS projection of 0.2 tpd for DFW 

nonattainment area point source growth, as described in Section 2.3.2.1.2. In general, ozone 

concentrations in 2012 using the ERC registry and DERC flow control limit growth were slightly 

higher in the DFW nonattainment area than the TIPI-REMI-EGAS growth, though some 

decreases from NOX titration were observed near the source locations. Figure 51, Att. 3: June 14 

Eight-Hour Ozone Max Difference Tile Plot Comparing ERC and DERC Flow Control Limit to

TIPI-REMI-EGAS Growth below shows the difference of the maximum eight-hour ozone 

concentrations on June 14 with the ERC and DERC flow control limit versus the TIPI-REMIEGAS growth. The blue colors represent ozone reductions while yellow through red represent 

ozone increases due to the ERC and DERC flow control NOX limit. Similar results occurred for 

all days during the June 2006 episode.

Figure 51, Att. 3: June 14 Eight-Hour Ozone Max Difference Tile Plot Comparing 

ERC and DERC Flow Control Limit to TIPI-REMI-EGAS Growth
B-153

By modeling the ERC registry and DERC flow control limit, which increased the NOX emissions 

in the DFW nonattainment area from the final future baseline modeling, the 2012 future year 

ozone design values (DVFs) also increased. Table 91, Att. 3: 2012 Future Design Values Using 

the ERC registry and DERC Flow Control Limit or TIPI-REMI-EGAS Growth shows that every 

DFW area monitor’s DVF was unchanged or increased slightly by modeling with the ERC registry 

and the DERC flow control limit for growth. However when the DVFs are truncated according to 

EPA’s final design value calculation method, the 2012 DVFs are unchanged except for Dallas 

Hinton.

Table 91, Att. 3: 2012 Future Design Values Using the ERC registry and DERC Flow 

Control Limit or TIPI-REMI-EGAS Growth

Monitor

2012 DVF w/ 

TIPI-REMI-EGAS 

(ppb)

2012 DVF w/ 

DERC Flow 

Control Limit 

(ppb)

DVF

Difference 

(ppb)

Denton C56 77.03 77.30 0.27

Eagle Mountain Lake C75 78.06 78.28 0.22

Keller C17 76.45 76.60 0.15

Grapevine Fairway C70 76.17 76.44 0.27

Fort Worth Northwest C13 75.36 75.49 0.13

Frisco C31 74.45 74.58 0.13

Weatherford Parker County C76 72.71 72.92 0.21

Dallas North C63 71.15 71.31 0.16

Dallas Exec Airport C402 70.58 70.73 0.15

Cleburne C77 70.85 70.98 0.13

Arlington C61 70.32 70.45 0.13

Dallas Hinton C401 67.89 68.04 0.15

Pilot Point C1032 67.35 67.53 0.18

Midlothian Tower C94 66.63 66.73 0.10

Rockwall Heath C69 63.27 63.29 0.02

Midlothian OFW C52 62.24 62.32 0.08

Kaufman C71 60.42 60.42 0.00

Granbury C73 69.66 69.78 0.12

Greenville C1006 59.96 59.97 0.01 # Pilot Point C1032, Midlothian Tower C94, and Midlothian OFW C52 did not measure enough data from 2004 

through 2008 to calculate a complete baseline design value. A DVB was calculated using all available data for the 

DVFs shown.

* Granbury C73 and Greenville C1006 are outside the 1997 eight-hour ozone NAAQS DFW nonattainment area.

The results of the ERC registry and DERC flow control limit sensitivity complement the DFW 

SIP revision modeling with the TIPI-REMI-EGAS growth as both indicate the DFW area will 

attain the 1997 eight-hour ozone standard by June 2013.