ERG No. 0227.00.001.001 

EMISSIONS FROM OIL AND GAS PRODUCTION FACILITIES 

FINAL REPORT 

TCEQ Contract 582-7-84003 

Work Order No. 1 

Prepared for: 

Mr. Bertie Fernando, P.E. 

Texas Commission on Environmental Quality 

Air Quality Division 

Mail Code 206 

P.O. Box 13087 

Austin, Texas 78711-3087 

Prepared by: 

Eastern Research Group, Inc. 

1600 Perimeter Park Drive 

Suite 200 

Morrisville, North Carolina 27560 

August 31, 2007
i 

TABLE OF CONTENTS 

Section Page

LIST OF TABLES......................................................................................................................... iii 

LIST OF ACRONYMS ...................................................................................................................v 

EXECUTIVE SUMMARY ........................................................................................................... vi 

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

 1.1 Purpose and Objectives........................................................................................ 1-1 

 1.2 Report Organization............................................................................................. 1-2 

2. CHARACTERIZATION OF OIL AND GAS SOURCES INVENTORIED.................. 2-1 

 2.1 Definition of Oil and Gas Sources and SCCs ...................................................... 2-1 

 2.2 Emission and Activity Data Issues ...................................................................... 2-2 

 2.2.1 Onshore Exploration Sources .................................................................. 2-2 

 2.2.2 Onshore Production Sources.................................................................. 2-12 

 2.2.3 Offshore Production Sources ................................................................. 2-16 

3. SUMMARY OF 2005 BASE YEAR EMISSIONS......................................................... 3-1 

 3.1 Oil and Gas Emissions Summary ........................................................................ 3-1 

 3.2 Source Category Contributions by Pollutant ..................................................... 3-30 

 3.2.1 Carbon Monoxide Emissions................................................................. 3-30 

 3.2.2 Nitrogen Oxide Emissions ..................................................................... 3-30 

 3.2.3 Volatile Organic Compound Emissions................................................. 3-31 

 3.2.4 Sulfur Dioxide Emissions ...................................................................... 3-31 

 3.2.5 Particulate Matter Emissions ................................................................. 3-31 

 3.3 Comparison of Emissions by County ................................................................ 3-32 

 3.3.1 Onshore Exploration .............................................................................. 3-32 

 3.3.2 Onshore Production ............................................................................... 3-45 

 3.3.3 Offshore Production Sources ................................................................. 3-46 

 3.4 Comparison of Emissions by Attainment Status ............................................... 3-47 
ii 

TABLE OF CONTENTS (Cont.) 

Section Page

4. EMISSION PROJECTIONS ........................................................................................... 4-1 

 4.1 Projections Methodology..................................................................................... 4-1 

 4.2 Summary of Oil and Gas Area Sources Projected Emissions.............................. 4-5 

5. REFERENCES ................................................................................................................ 5-1 

Appendix A – Documentation of Exploration Sources Emissions 

Appendix B – Documentation of Production Sources Emissions 

Appendix C – Documentation of Offshore Sources Emissions 
iii 

LIST OF TABLES 

Table Page

2-1a Identification of Source Categories Addressed in the Texas Oil and Gas Emission 

Inventory in the Onshore Exploration Grouping ............................................................. 2-3 

2-1b Identification of Source Categories Addressed in the Texas Oil and Gas Emission 

Inventory in the Onshore Production Grouping............................................................... 2-3 

2-1c Identification of Source Categories Addressed in the Texas Oil and Gas Emission 

Inventory in the Offshore Production Grouping.............................................................. 2-4 

2-2a Assignment of SCCs to Texas Oil and Gas Sources in the Onshore Exploration 

 Grouping .......................................................................................................................... 2-4 

2-2b Assignment of SCCs to Texas Oil and Gas Sources in the Onshore Production 

 Grouping .......................................................................................................................... 2-5 

2-2c Assignment of SCCs to Texas Oil and Gas Sources in the Offshore Production 

 Grouping .......................................................................................................................... 2-8 

3-1 Summary of Annual Statewide Criteria Pollutant Emissions.......................................... 3-2 

3-2 Summary of Ozone Season Daily (OSD) Statewide Criteria Pollutant Emissions ......... 3-4 

3-3 Summary of Oil and Gas Category Emission Contribution Rankings by Pollutant........ 3-6 

3-4a County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions 

 for Exploration Sources ................................................................................................... 3-8 

3-4b County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions 

 for Production Sources................................................................................................... 3-17 

3-4c County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions 

 for Offshore Platforms ................................................................................................... 3-26 

3-5 Combined County-Level Emission Estimates for All Sources Included 

 in the Inventory.............................................................................................................. 3-33 

3-6 Summary of Oil and Gas Area Source Emissions by Attainment Status ...................... 3-48 

4-1a Texas Counties in the Onshore-Gulf Coast EIA Region ................................................. 4-2 

4-1b Texas Counties in the Onshore-Southwest EIA Region.................................................. 4-3 

4-1c Texas Counties in the Onshore-Shallow EIA Region...................................................... 4-3 

4-1d Area-Blocks in the Offshore-Deep EIA Region .............................................................. 4-4 

4-2a Projected EIA Production ................................................................................................ 4-5 

4-2b Projected EIA Production (MMBtu)................................................................................ 4-5 

4-2c Final Projection Factors by EIA Region.......................................................................... 4-5 
iv 

LIST OF TABLES (Continued) 

Table Page

4-3a CO Projected Emissions by Location and Type .............................................................. 4-6 

4-3b NOx Projected Emissions by Location and Type............................................................. 4-6 

4-3c PM10 PRI Projected Emissions by Location and Type .................................................... 4-6 

4-3d PM2.5 PRI Projected Emissions by Location ................................................................... 4-7 

4-3e SO2 Projected Emissions by Location and Type ............................................................. 4-7 

4-3f VOC Projected Emissions by Location and Type ........................................................... 4-7 
v 

LIST OF ACRONYMS 

Acronym Definition

API American Petroleum Institute 

CAPP Canadian Association of Petroleum Producers 

CBM Coal Bed Methane 

CERR Consolidated Emissions Reporting Rule 

CO Carbon Monoxide 

DOE U.S. Department of Energy 

EIA Energy Information Administration 

ERG Eastern Research Group 

GPA Gas Processors Association 

HARC Houston Advanced Research Center 

hp Horsepower 

H2S Hydrogen Sulfide 

MMBBL Million Barrels 

MMBTU Million British Thermal Units 

MMS Minerals Management Service 

MMscf Million Standard Cubic Feet 

Mscf Thousand Standard Cubic Feet 

MW Molecular Weight 

NEI National Emissions Inventory 

NH3 Ammonia 

NIF NEI Input Format 

NOx Nitrogen Oxides 

OFW Offshore Federal Waters 

OSW Offshore State Waters 

OE Onshore Exploration 

OP Onshore Production 

OSD Ozone Season Daily 

PM Particulate Matter 

PM10 PM with particle diameter less than 10 micrometers 

PM2.5 PM with particle diameter less than 2.5 micrometers 

SCC Source Classification Code 

scf Standard Cubic Feet 

SIP State Implementation Plan 

SO2 Sulfur Dioxide 

TCEQ Texas Commission on Environmental Quality 

TexAER Texas Air Emissions Repository 

THC Total Hydrocarbons 

TRC Texas Railroad Commission 

TXCO Texas Exploration Company 

US EPA United States Environmental Protection Agency 

VOC Volatile Organic Compounds 

WRAP Western Regional Air Partnership 

WYDEQ Wyoming Department of Environmental Quality 
vi 

EXECUTIVE SUMMARY 

The purpose of this study was to compile a comprehensive emissions inventory for 

onshore and offshore oil and gas exploration and production facilities in Texas for the base year 

2005. The inventory was compiled for criteria pollutant emissions as permissible with available 

emission factors. Attempts were also made to include lead and ammonia (NH3) emissions as 

appropriate; however, this was not done due to a lack of credible emission factors for these 

pollutants. The emissions inventory will be used for general inventory compilation and tracking 

purposes, trends analysis, and potential control strategy development purposes. Related to this, 

the inventory will also potentially serve as improved input data to photochemical air quality 

dispersion modeling, emissions sensitivity analyses, State Implementation Plan (SIP), and rule 

development activities. 

This project addressed the development of an emissions inventory for oil and gas industry

sources in Texas that have not been well characterized previously. The oil and gas exploration 

and production industry is a large and complex one with many different potential sources of air 

pollution. The larger sources such as refineries, bulk plants, and large transmission/distribution 

stations are generally well identified and typically treated as major point sources for inventory 

purposes. The Texas Commission on Environmental Quality (TCEQ) already has good quality 

inventories on these sources. The industry, however, contains many smaller and much more 

diffuse sources that occur in the course of exploring for oil and gas and bringing these products 

to the marketplace. Many of these sources may be identified as non-point or area sources, and 

they have emissions below major source thresholds limits. These area sources are large in 

number and are geographically dispersed. Historically many of these area oil and gas sources 

have not been adequately inventoried. These “missing” source emissions, their identification and 

locations can be significant. 

The goals of this study were to identify the extent of the area oil and gas source 

categories, including defining new categories not previously identified, and to develop 

preliminary baseline emissions estimates for as many of the identified categories as possible 

using readily available data from studies completed in the last few years. The emissions 

estimates were developed using top-down, area source methods (i.e., the inventory was not 

intended to be on a source-by-source, bottom-up basis). This approach was taken to be 

consistent with the resources and time limitations that are available for the project. The oil and 

gas industry in Texas is very large and diverse. Compiling an inventory on a point source basis 

for a state the size of Texas would be very resource intensive and costly. By applying these 

broader area source methods, preliminary emission estimates could be obtained that start to give 

some reference points for the level of emissions attributable to these previously uncharacterized 

sources. It also helps provide input on where effort should be placed in the future to refine and 

improve the data. 

The oil and gas source categories that were the focus of initial investigations included the 

following. Sources were organized into three groups – onshore exploration, onshore production, 

and offshore production. 

Exploration sources: 
vii 

• Drilling Rigs 

• Gas Well Completions 

• Oil Well Completions 

• Gas Well Pneumatic Devices 

• Oil Well Pneumatic Devices 

Production sources: 

• Wellheads 

• Compressor Engines 

• Dehydrators 

• Heater Treaters 

• Oil and Condensate Storage Tanks 

• Loading of Oil and Condensate for Transportation 

• Pump and Piping Component Fugitive Losses 

• Coal Bed Methane (CBM) Engines 

Offshore platforms: 

• Oil and Gas Exploration and Production Platforms Operating in Texas State 

Waters (0-10 miles from shore) 

• Oil and Gas Platforms Operating in Federal Waters (>10-25 miles from shore) 

These are the source types included in the emissions inventory. In some cases, these source 

categories have multiple emission sources associated with them. For example, for Drilling Rigs, 

emission estimates were assembled for drilling rig power engines and for mud degassing 

operations. 

Emission estimates were constructed for each source at the county level. Both annual 

and ozone season daily emission estimates were calculated. Much of the activity data used to 

develop the emission estimates came from records maintained by the Texas Railroad 

Commission (TRC). The 2005 base year emission estimates were also projected to future years. 

Projection years included 2010, 2015, and 2020. A procedure involving the use of U.S 

Department of Energy (DOE), Energy Information Administration (EIA) oil and gas production 

growth estimates for the Texas region was used to perform the projections. 

For emissions of nitrogen oxides (NOx), onshore drilling rig engine and compressor 

engine sources were found to contribute the greatest amounts to statewide area source oil and gas 

emissions. These two categories were responsible for roughly 95% of statewide emissions from 

oil and gas area sources. The largest sources of volatile organic compounds (VOC), comprising 

62.4% of the state area sources oil and gas total, were found to be onshore production glycol 

dehydrators (26.9%), onshore condensate storage tanks (22.9%), and onshore gas production 

wellheads (12.6%). Sulfur dioxide (SO2) emissions were dominated by onshore drilling rig 

engines (97.4%). Similarly for carbon monoxide (CO), the largest oil and gas area sources were 

onshore production compressor engines (70.5%), onshore drilling rig engines (21.8%), offshore 

platform compressor engines (3.6%), and onshore production gas well completions (1.7%). 

Emissions of particulate matter (PM) from oil and gas area sources, PM10 and PM2.5, were found 

to be dominated by onshore production drilling rig engines (53.8% for PM10 and 53.3% for 
viii 

PM2.5) and onshore compressor engines (42.5% for PM10 and 43% for PM2.5). The final 2005 

emission estimates were put into National Emissions Inventory (NEI) Input Format (NIF) to 

facilitate reporting to EPA under Consolidated Emissions Reporting Rule (CERR) requirements. 
1-1 

1.0 INTRODUCTION 

1.1 Purpose and Objectives 

The purpose of this study is to compile a comprehensive emissions inventory for onshore 

oil and gas exploration and production facilities in Texas and for offshore production platforms 

(within 25 miles of the Texas coast) for the base year 2005. The list of onshore oil and gas 

sources addressed in the study, as defined in the Work Order, is as follows. 

Exploration sources including: 

• Drilling Rigs 

- diesel engines 

- degassing of drilling muds 

• Gas Well Completions 

- flaring 

- venting 

• Oil Well Completions 

- flaring 

- venting 

• Gas Well Pneumatic Devices 

• Oil Well Pneumatic Devices 

Production sources including: 

• Wellheads 

• Compressor Engines 

• Dehydrators 

• Heater Treaters 

• Oil and Condensate Storage Tanks 

• Loading of Oil and Condensate for Transportation 

• Pump and Piping Component Fugitive Losses 

• Coal Bed Methane (CBM) Pump Engines 

Offshore oil and gas production platforms were inventoried in both state waters off the coast, 

which spans from shore out to a distance of 10 miles, and in federal waters out to a distance of 

25 miles (basically the band between 10 and 25 miles). Emissions from oil and gas exploration 

sources were also addressed for the state waters area. The inventory was compiled for criteria 

pollutant emissions. 

This study primarily pertains to the development of an emissions inventory for oil and 

gas industry sources in Texas that have not been well characterized previously. The oil and gas 

exploration and production industry is large and complex in Texas with many different potential 

sources of air pollution. The larger sources in the state such as refineries, bulk plants, and large 

transmission/distribution stations are generally well identified and typically treated as major 

point sources for inventory purposes. The TCEQ already has good quality inventories on these 

sources. The industry though contains many smaller and much more diffuse sources that occur 

in the course of exploring for oil and gas and bringing these products to the marketplace. Many 
1-2 

of these sources fit the definition of being non-point or area sources, i.e., they have emissions 

below major sources thresholds, they are large in number, and are geographically dispersed. 

Historically, many of these area oil and gas sources have not been adequately identified and 

inventoried. Identifying, locating, and quantifying these “missing” source emissions is a 

significant task. 

The goals of this study are to identify the extent of these area oil and gas source 

categories, including defining new categories not previously inventoried, and to develop 

preliminary baseline emissions estimates for 2005 for as many of the identified categories as 

possible using currently available data (i.e., time and resources for extensive surveys and/or new 

source testing are not available). Studies within the last three years by TCEQ, the Houston 

Advanced Research Center (HARC), and the Western Regional Partnership (WRAP) have 

produced data and methods that can be applied for the purposes of this inventory (HARC, 2005; 

HARC, 2006a; HARC, 2006b; WRAP, 2005). The emissions estimates were developed using 

top-down, area source methods (i.e., the inventory was not estimated on a source-by-source, 

bottom-up basis). Compiling an inventory on a point source basis would be very resource 

intensive and take more time than was available for this study. By applying broader area source 

methods, preliminary emission estimates can be obtained that start to give some reference points 

for the level of emissions attributable to these previously uncharacterized sources. It also helps 

provide input on where effort should be placed in the future to refine and improve the data. The 

study results will be used for general inventory compilation and tracking purposes, trends 

analysis, and potential control strategy development purposes. The results can also serve as 

improved input data to photochemical air quality dispersion modeling, emissions sensitivity 

analyses, SIP planning, and possible rule development activities. 

For planning purposes, the 2005 base year estimates were projected to future years 2010, 

2015, and 2020. Also, the final base year inventory estimates were provided in National 

Emissions Inventory (NEI) Input Format (NIF) for the purposes of submittal to EPA in order to 

comply with Consolidated Emissions Reporting Rule (CERR) requirements, and to facilitate 

entry of the data into the state’s TexAER (Texas Air Emissions Repository) database. 

1.2 Report Organization 

Section 2.0 of this report more thoroughly identifies the oil and gas source categories 

addressed in the emissions inventory and describes how each emission source is being treated in 

terms of the inventory development. The emissions aspects of each category are described, 

along with an identification of the pollutants being inventoried for each. Each emission source is 

assigned a Source Classification Code (SCC) for tracking purposes and a table of all SCCs is 

presented. Section 2.0 provides explanations of any assumptions or manipulations that had to be 

made to source categories to facilitate the development of area source emission estimates. 

The summary results of the 2005 emissions inventory development process are presented 

in Section 3.0. Summary emissions tables are provided on a statewide and county level basis for 

both annual and ozone season daily (OSD) emissions. The emissions estimates are described in 

terms of known uncertainties and weaknesses, and suggestions for possible improvements are 

provided. Discussion and analysis is also provided to compare and contrast how sources rank 
1-3 

relative to each other for each pollutant. Emissions are also presented to show geographic 

concentrations by county. 

Section 4.0 presents information and data on the projection of the 2005 base year 

estimates to three future years (2010, 2015, and 2020). The data and methods used to construct 

projection techniques are described and statewide and county level emission estimate are 

provided for all three projection years. Section 5.0 contains reference citations for the report. 

The full documentation and detailed county level 2005 emissions estimates data for each 

inventoried source category are provided in Appendices A, B, and C. The appendices address 

the onshore exploration, onshore production, and offshore production source groupings, 

respectively. Each appendix discussion provides full and transparent documentation on how

each category’s estimates were derived, the procedures and assumptions used, and the input 

emission factor and activity data applied to determine all emission estimates. 
2-1 

2.0 CHARACTERIZATION OF OIL AND GAS SOURCES INVENTORIED 

2.1 Definition of Oil and Gas Sources and SCCs 

The majority of the list of onshore oil and gas exploration and production source 

categories addressed in this project was taken from a Western Regional Air Partnership (WRAP) 

study on area source oil and gas emissions (WRAP, 2005). In the WRAP study, volatile organic 

compounds (VOC), nitrogen oxides (NOx), carbon monoxide (CO), and sulfur dioxide (SO2) 

emission estimates were generated for several non-point oil and gas sources in 14 states of the 

WRAP region (note: not all applicable pollutants were estimated for every source). Many of 

these same sources are prevalent in Texas. Other oil and gas emissions sources were specified 

by TCEQ and in oil and gas industry data produced by the Minerals Management Service 

(MMS) for offshore oil and gas platforms in Texas state waters and federal waters (MMS, 2004; 

TCEQ, 2007b). The TCEQ provided information on the names and location coordinates for over 

200 oil and gas platforms located within 25 miles of the Texas coastline. The MMS information 

characterizes emissions from 16 platform emission unit types (e.g., boiler, engines, turbines, 

amine units, glycol dehydrators, fugitives) at the equipment level for base year 2005. Currently, 

base year 2005 estimates are being finalized; however, MMS has provided authorization for 

TCEQ to use these draft data for the purposes of this project, provided the data are marked as 

draft and are not released, cited, quoted, or otherwise used outside of TCEQ until such time as 

MMS publishes the data as final. 

In this project, the oil and gas source categories have been divided into three major 

groups: onshore exploration sources, onshore production sources, and offshore production 

platforms. For exploration and production, depending on the definition of the operations used, 

there is clearly some potential for overlap occurring between some emission sources, i.e., a 

source such as completion venting could be considered exploration or production. For the 

purposes of this project, exploration, production, and offshore sources are identified as follows. 

Exploration sources include: 

• Drilling Rigs 

• Gas Well Completions 

• Oil Well Completions 

• Gas Well Pneumatic Devices 

• Oil Well Pneumatic Devices 

Production sources include: 

• Wellheads 

• Compressor Engines 

• Dehydrators 

• Heater Treaters 

• Oil and Condensate Storage Tanks 

• Loading of Oil and Condensate for Transportation 

• Pump and Piping Component Fugitive Losses 

• Coal Bed Methane Pump Engines 
2-2 

Offshore stationary sources include: 

• Oil and Gas Exploration and Production Platforms Operating in Texas State 

Waters (sources 0-10 miles from shore) 

• Oil and Gas Production Platforms Operating in Federal Waters (sources >10-25 

miles from shore) 

Emission totals in Section 3.0 are presented according to these groupings. 

Table 2-1 (a, b, and c) provides a summary of the source categories evaluated in the 

emissions inventory (according to their grouping), the specific operations or processes that 

generate air emissions, and an identification of the pollutants associated with each source. 

Table 2-2 (organized as a, b, and c for the three groupings) further delineates these source 

category types into specific emission processes, and presents SCCs for each individual emissions 

process. For onshore exploration and production sources, most of the SCC assignments originate 

as new codes proposed by TCEQ (TCEQ, 2007a) or codes proposed by ERG as a result of 

assessing all of the emission processes included in the inventory. The offshore SCC assignments 

are a combination of ones on the official EPA list and ones proposed by ERG. 

2.2 Emission and Activity Data Issues 

This discussion further describes and clarifies the oil and gas emission sources included 

in the inventory. Factors affecting emissions are discussed and the rationales for using certain 

assumptions (related to source operation) for the purposes of the inventory are explained. 

General information is provided on how source emissions will be estimated. The detailed 

procedural description of the estimation processes and the accompanying input data and 

calculations are presented in Appendices A, B, and C. The inventory was compiled for criteria 

pollutant emissions as permissible with available emission factors. Attempts were also made to 

include lead and NH3 emissions as appropriate; however, this was not done due to a lack of 

credible emission factors. 

2.2.1 Onshore Exploration Sources

Drilling Rigs/Engines 

This category pertains to the engines used to generate power to run drilling rigs in the 

exploration field. These engines are assumed to be burning diesel fuel. Emission factors for 

diesel-fired engines operating drilling rigs were taken from AP-42 (US EPA, 1996). Drilling rig 

engines were assumed to operate with a maximum horsepower (hp) greater than 600 hp 

(Engeser, 2004). For SO2 emissions, the weight percent of sulfur used in the diesel fuel (low 

sulfur fuel) is assumed to be 3400 ppmv or 0.34% by weight for every county in Texas (EPA, 

2004b). It is possible that some counties in Texas may be using fuels with a lower or higher 

sulfur content. 
2-3 

Table 2-1a. Identification of Source Categories Addressed in the Texas Oil and Gas 

Emission Inventory in the Onshore Exploration Grouping 

Onshore Exploration 

Source Type Specific Emission Sources Potential Pollutantsa

Diesel engines to run electricity generators SO2, NOx, VOC, 

Drilling Rigs PM10, PM2.5, CO 

Drill mud degassing (open pits or storage tanks) VOC 

Emissions from flaring from the gas well 

completion phase CO, NOX, VOC 

Gas Well Completion 

Emissions from venting from the gas well 

completion phase VOC 

Emissions from flaring from the oil well 

completion phase CO, NOX, VOC, SO2

Oil Well Completion 

Emissions from venting from the oil well 

completion phase VOC 

Gas Well Pneumatic 

Devices 

Fugitive emissions from pneumatic devices used 

during gas well exploration and production VOC 

Oil Well Pneumatic 

Devices 

Fugitive emissions from pneumatic devices used 

during oil well exploration and production VOC 

a PM = Particulate Matter 

Table 2-1b. Identification of Source Categories Addressed in the Texas Oil and Gas 

Emission Inventory in the Onshore Production Grouping 

Onshore Production 

Source Type Specific Emission Sources 

Potential 

Pollutantsa

Oil and Gas Well Wellheads Emissions from wellhead assemblies 

and rod pumps VOC 

Compressor Engines Combustion emissions from compressor 

engines associated with oil and gas production 

SO2, NOx, VOC, 

PM10, PM2.5, CO 

Dehydrators/Separators Emissions from glycol dehydrator reboilers VOC 

Heater Treaters Emissions from natural gas-fired 

heater treaters NOx, CO 

Oil and Condensate Storage 

Tanks 

Working, breathing, and flashing losses from oil 

and condensate storage tanks VOC 

Loading of Oil and Condensate Fugitive emissions from truck and/or railcar 

loading VOC 

Pump and Piping Component 

Fugitive Losses 

Fugitive emissions from pumps 

and piping components VOC 

Coal Bed Methane Pump 

Engines 

Natural gas engine emissions 

used to de-water coal beds 

SO2, NOx, VOC, 

PM10, PM2.5, CO 

a PM = Particulate Matter 
2-4 

Table 2-1c. Identification of Source Categories Addressed in the Texas Oil and Gas 

Emission Inventory in the Offshore Production Grouping 

Offshore Production 

Source Type Specific Emission Sources Potential Pollutantsa

Offshore Platforms – 

State Waters 

Stack and fugitive process emissions for oil 

and natural gas platforms operating in the 

Texas state waters (0-10 miles from shore) 

SO2, NOx, VOC, 

PM10, PM2.5, CO 

Offshore Platforms – 

Federal Waters 

Stack and fugitive process emissions for oil 

and natural gas platforms operating in the 

federal waters (>10-25 miles from shore) 

SO2, NOx, VOC, 

PM10, PM2.5, CO 

a PM = Particulate Matter 

Table 2-2a. Assignment of SCCs to Texas Oil and Gas Sources 

in the Onshore Exploration Grouping 

Onshore Exploration Source 

Types and Emission Processes Proposed SCC SCC Description (abbreviated)a

Drilling Rigs 

- Diesel Engines 2310001200 ERG proposed SCC; Drilling Rig Engines 

using diesel fuel 

- Mud Degassing 2310001100 ERG proposed SCC; Mud Degassing Activities 

Gas Well Completion – Flaring 2310021701 ERG proposed SCC; Flaring during Gas Well 

Completions 

Gas Well Completion – Venting 2310021702 ERG proposed SCC; Venting during Gas Well 

Completions 

Oil Well Completion – Flaring 2310011701 ERG proposed SCC; Flaring during Oil Well 

Completions 

Oil Well Completion – Venting 2310011702 ERG proposed SCC; Venting during Oil Well 

Completions 

Gas Well Pneumatic Pumps 2310021401 ERG proposed SCC; Gas Well Pneumatic 

Pumps 

Oil Well Pneumatic Pumps 2310011401 ERG proposed SCC; Oil Well Pneumatic 

Pumps 

aUnless otherwise noted, SCCs were obtained from EPA’s official SCC list (US EPA, 2004a). 
2-5 

Table 2-2b. Assignment of SCCs to Texas Oil and Gas Sources 

in the Onshore Production Grouping

Onshore Production Source 

Types and Emission Processes 

Proposed 

SCC SCC Description (abbreviated)a

Oil Well – Wellhead 2310011450 ERG Proposed SCC; Onshore Oil Production – 

Wellhead Activities 

Gas Well – Wellhead 2310021450 ERG Proposed SCC; Onshore Natural Gas 

Production – Wellhead Activities 

Compressor Engines 

- 2-cycle, lean 2310021100 TCEQ TexAER SCC; Onshore Natural Gas Production – Compressor Engines: 2-cycle, lean 

- 2-cycle, lean, less than 50hp 

2310021101 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 2-cycle, 

lean, less than 50hp 

- 2-cycle, lean, 50-499hp 

2310021102 

ERG Proposed SCC; Onshore Natural Gas 

Production – Compressor Engines: 2-cycle, 

lean, 50-499hp 

- 2-cycle, lean, 500+hp 

2310021103 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 2-cycle, 

lean, 500+hp 

- 4-cycle, lean 2310021200 TCEQ TexAER SCC; Onshore Natural Gas Production – Compressor Engines: 4-cycle, lean 

- 4-cycle, lean, less than 50hp 

2310021201 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, 

lean, less than 50hp 

- 4-cycle, lean, 50-499hp 

2310021202 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, 

lean, 50-499hp 

- 4-cycle, lean, 500+hp 

2310021203 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, 

lean, 500+hp 

- 4-cycle, rich 2310021300 TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, rich 

- 4-cycle, rich, less than 50hp 

2310021301 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, rich, 

less than 50hp 

- 4-cycle, rich, 50-499hp 

2310021302 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, rich, 

50-499hp 

- 4-cycle, rich 500+hp 

2310021303 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, rich 

500+hp 

- 4-cycle, rich w/NSCR 

2310021321 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, rich 

w/NSCR 

- 4-cycle, rich, less than 50hp 

 w/NSCR 

2310021331 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, rich, 

less than 50hp w/NSCR 
2-6 

Table 2-2b. Assignment of SCCs to Texas Oil and Gas Sources 

in the Onshore Production Grouping (Continued)

Onshore Production Source 

Types and Emission Processes 

Proposed 

SCC SCC Description (abbreviated)a

- 4-cycle, rich, 50-499hp 

w/NSCR 

2310021341 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, rich, 

50-499hp w/NSCR 

- 4-cycle, rich, 500+hp w/NSCR 2310021351 

TCEQ TexAER SCC; Onshore Natural Gas 

Production – Compressor Engines: 4-cycle, rich, 

500+hp w/NSCR 

Gas Well – Dehydrator 2310021400 TCEQ Proposed SCC; Onshore Natural Gas Production – Dehydrator 

Oil Well – Heater Treater 2310011100 ERG Proposed SCC; Onshore Oil Production – Heater Treater 

Oil Well – Oil Storage Tanks 2310011020 TCEQ Proposed SCC; Onshore Oil Production – Crude Oil Tank 

Gas Well – Condensate Storage 

Tanks 2310011010 ERG Proposed SCC; Onshore Oil Production – Condensate Tank 

Tank Truck/Railcar Loading – Oil 2310011201 ERG Proposed SCC; Onshore Oil Production – 

Tank Truck/Railcar Loading: Condensate

Tank Truck/Railcar Loading – 

Condensate 2310011202 ERG Proposed SCC; Onshore Oil Production – Tank Truck/Railcar Loading: Oil

Oil Well – Fugitive Emissions 

- Connection 2310011501 ERG Proposed SCC; Onshore Oil Production – 

Fugitives: Connectors

- Flange 2310011502 ERG Proposed SCC; Onshore Oil Production – 

Fugitives: Flanges

- Open End 2310011503 ERG Proposed SCC; Onshore Oil Production – 

Fugitives: Open Ended Lines

- Pump 2310011504 ERG Proposed SCC; Onshore Oil Production – 

Fugitives: Pumps

- Valve 2310011505 ERG Proposed SCC; Onshore Oil Production – 

Fugitives: Valves

- Other 2310011506 ERG Proposed SCC; Onshore Oil Production – 

Fugitives: Other

Gas Well – Fugitive Emissions 

- Connection 2310021501 ERG Proposed SCC; Onshore Natural Gas Production – Fugitives: Connectors

- Flange 2310021502 ERG Proposed SCC; Onshore Natural Gas Production – Fugitives: Flanges

- Open End 2310021503 ERG Proposed SCC; Onshore Natural Gas Production – Fugitives: Open Ended Lines

- Pump 2310021504 ERG Proposed SCC; Onshore Natural Gas Production – Fugitives: Pumps

- Valve 2310021505 ERG Proposed SCC; Onshore Natural Gas Production – Fugitives: Valves
2-7 

Table 2-2b. Assignment of SCCs to Texas Oil and Gas Sources 

in the Onshore Production Grouping (Continued)

Onshore Production Source 

Types and Emission Processes 

Proposed 

SCC SCC Description (abbreviated)a

- Other 2310021506 ERG Proposed SCC; Onshore Natural Gas 

Production – Fugitives: Other

Coal Bed Methane Pump Engines 2310021800 ERG proposed SCC; Coal Bed Methane Pump 

Engines 

aUnless otherwise noted, SCCs were obtained from EPA’s official SCC list (US EPA, 2004a). 
2-8 

Table 2-2c. Assignment of SCCs to Texas Oil and Gas Sources

in the Offshore Production Grouping

Offshore Production Source 

Types and Emission Processes 

Proposed 

SCC SCC Description (abbreviated)a

Offshore Platforms (State & Federal Waters) 

- Boiler/Heater/Treater, <10 

 MMBTU/hr 10200603 External Industrial Combustion: Natural Gas (<10 MMBTU/hr) 

- Diesel Engine 20200102 Internal Industrial Combustion Reciprocating Engine: Diesel Oil 

- Natural Gas Turbine 20200201 Internal Industrial Combustion: Turbine: Natural Gas 

- Natural Gas Engine, 2-cycle 

 lean 20200252 Internal Industrial Combustion: Natural Gas (2-cycle-lean) 

- Natural Gas Engine, 4-cycle 

 Rich 20200253 Internal Industrial Combustion: Natural Gas (4-cycle-rich) 

- Natural Gas Engine, 4-cycle 

 Clean 20200254 Internal Industrial Combustion: Natural Gas (4-cycle-lean) 

- Natural Gas Engine, 2-cycle 

 Clean 20200255 Internal Industrial Combustion: Natural Gas (2-cycle-clean) 

- Natural Gas Engine, 4-cycle 

 Clean 20200256 Internal Industrial Combustion: Natural Gas (4-cycle-clean) 

- Cold Vents 31000123 Oil and Gas Production – Vents 

- Losses from Flashing 31000132 Oil and Gas Production - Flashing Losses 

- Pneumatic Pumps 31000224 Oil and Gas Production – Pneumatic Devices 

- Glycol Dehydrators using 

 Triethylene Glycol 31000301 Oil and Gas Production - Glycol Dehydrators using TEG 

- Pressure Relief Valves 31000307 Oil and Gas Production - Relief Valves 

- Fugitive Emissions: Other 31088811 Oil and Gas Production - Fugitive Emissions 

- Storage Tank: Condensate 40400321 Oil and Gas Production – Storage Tank 

Condensate 

- Storage Tank: Crude Oil 40400322 Oil and Gas Production – Storage Tank: Crude 

Oil 

- Natural Gas Engines: 4-Cycle, 

Rich 

2310002001 ERG Proposed SCC; Offshore Production – 

Compressor Engines: 4-cycle rich 

- Storage Tanks - Condensate 2310002010 ERG Proposed SCC; Offshore Production - 

Storage Tanks: Condensate 

- Storage Tanks - Crude Oil 2310002020 ERG Proposed SCC; Offshore Production - 

Storage Tanks: Crude Oil 

- Natural Gas Turbines 2310002051 ERG Proposed SCC; Offshore Production – 

Turbines: Natural Gas 

- Boilers/Heaters 2310002100 ERG Proposed SCC; Offshore Production – 

Boilers/Heaters: Natural Gas 

- Diesel Engines 2310002105 ERG Proposed SCC; Offshore Production – 

Diesel Engines 

- Drilling Rig Engines 2310002200 ERG Proposed SCC; Offshore Production – 

Drilling Rig Engines 

- Loading: Barge - Oil 2310002201 ERG Proposed SCC; Offshore Production – 

Loading Operations via Barge: crude oil 
2-9 

Table 2-2c. Assignment of SCCs to Texas Oil and Gas Sources

in the Offshore Production Grouping (Cont.)

Offshore Production Source 

Types and Emission Processes 

Proposed 

SCC SCC Description (abbreviated)a

- Mud Degassing 2310002210 ERG Proposed SCC; Offshore Production – 

Mud degassing activities 

- Flare - pilot light 2310002301 ERG Proposed SCC; Offshore Production – 

Flares: continuous pilot light 

- Flare - flaring 2310002305 ERG Proposed SCC; Offshore Production – 

Flares: Flaring Operations 

- Glycol Dehydrators 2310002400 ERG Proposed SCC; Offshore Production – 

Glycol Dehydrators: triethylene glycol 

- Pneumatic Pumps-Gas and Oil 

Wells 

2310002401 ERG Proposed SCC; Offshore Production – 

Pneumatic Pumps: Gas and Oil Wells 

- Pressure/Level Controllers 2310002411 ERG Proposed SCC; Offshore Production – 

Pressure/Level Controllers 

- Cold Vents 2310002421 ERG Proposed SCC; Offshore Production – 

Cold Vents 

- Fugitives - Connectors: gas 

streams 

2310002501 ERG Proposed SCC; Offshore Production – 

Fugitives, Connectors: gas streams 

- Fugitives - Flanges: gas streams 2310002502 ERG Proposed SCC; Offshore Production – 

Fugitives, Flanges: gas streams 

- Fugitives - Valves: gas 2310002505 ERG Proposed SCC; Offshore Production – 

Fugitives, Valves: gas 

- Fugitives - Other: gas 2310002506 ERG Proposed SCC; Offshore Production – 

Fugitives, Other: gas 

- Fugitives - Connectors: oil 

streams 

2310002511 ERG Proposed SCC; Offshore Production – 

Fugitives, Connectors: oil streams 

- Fugitives - Flanges: oil 2310002512 ERG Proposed SCC; Offshore Production – 

Fugitives, Flanges: oil 

- Fugitives - Valves: oil 2310002515 ERG Proposed SCC; Offshore Production – 

Fugitives, Valves: oil 

- Fugitives - Other: oil 2310002516 ERG Proposed SCC; Offshore Production – 

Fugitives, Other: oil 

- Fugitives - Connectors: 

oil/water streams 

2310002521 ERG Proposed SCC; Offshore Production – 

Fugitives, Connectors: oil/water streams 

- Fugitives - Flanges: oil/water 2310002522 ERG Proposed SCC; Offshore Production – 

Fugitives, Flanges: oil/water 

- Fugitives - Valves: oil/water 2310002525 ERG Proposed SCC; Offshore Production – 

Fugitives, Valves: oil/water 

- Fugitives - Other: oil/water 2310002526 ERG Proposed SCC; Offshore Production – 

Fugitives, Other: oil/water 

aUnless otherwise noted, SCCs were obtained from EPA’s official SCC list (US EPA, 2004a). 
2-10 

All exploratory oil and gas drilling in Texas requires a permit. On the Texas Railroad 

Commission (TRC) website, a listing of year 2005 approved drilling permits was available, with 

the assumption being made that this would be typical for actual drilling activities that occurred in 

2005. It is possible that drilling permits approved in 2005, did not have actual drilling 

commence until 2006. Conversely, actual drilling may have taken place in 2005 under permit

approvals made in 2004. An additional parameter retrieved for each approved permit is well 

depth. 

For most of the drilling permit data, the “spud date”, or the date in which drilling 

commenced, and the completed drilling date are included. Thus, actual number of drilling days 

can be calculated for each permit. Unfortunately, the effort required for obtaining this 

information for over 11,000 permits was time and resource prohibitive. As an alternative, 

representative drilling profiles were developed for each county and wellbore type (vertical, 

horizontal, directional, etc.) by obtaining the number of days drilled (from spud date and 

completed drilling date) for the permit with the maximum well depth. A total of 430 countywellbore drilling profiles were developed and applied to over 11,000 permits. As expected, 

wellbore profiles that were “horizontal” took longer to drill significant depths when compared to 

“vertical” wellbores. Approximately 85% of identified drilling permits indicated the use of 

wellbore drilling. Using industry guidance, average horsepower ratings can be assigned for 

lightweight, intermediate, or heavyweight drilling operations (Engeser, 2004). These 

classifications are based on well depth. For example, lightweight rigs are generally used for well 

depths between 1,500 to 2,000 meters (4,900 – 6,500 feet). The average horsepower for 

lightweight rigs is 650 hp. Similar factors are available for intermediate and heavy weight rigs. 

Drilling operations are assumed to be 24-hours a day during the drilling period. Thus, total 

engine power output in terms of horsepower-hours (hp-hr) can be calculated for each permitted 

drilling operation, which in turn allows for the estimation of emissions.

Drilling Rigs/Mud Degassing 

Various drilling fluids or muds are used during the drilling process to cool and lubricate 

the drill bit. These muds are returned to the surface contaminated with organic materials from 

the well. Upon reaching the surface, offgasing occurs and VOC are emitted into the air. No 

VOC emission factor was found in AP-42 or elsewhere for mud degassing operations occurring 

during drilling activities. However, a VOC emission factor can be derived using information 

from an MMS study for offshore platforms (MMS, 2004). The VOC emission factor for mud 

degassing was derived from a total hydrocarbon (THC) emission factor used by the MMS in 

their studies of platforms in the Gulf of Mexico. For drilling fluids using water-based muds, the 

THC emission factor is 881.81 lbs/day. To convert to a VOC emission factor, it was assumed 

that 8.61% of THCs are VOCs by weight (GPA, 2004), and this value was applied to develop a 

VOC emission factor: 

EFVOC = (881.81 lb THC/day) * (VOC wt%) 

EFVOC = (881.81) * (8.61/100) = 75.93 lb VOC/day 

For mud degassing activities, the number of drilling days per operation (obtained from TRC 

data) will be applied to the VOC emission factor to determine emissions. 
2-11 

Oil and Gas Well Completions 

After drilling and casing a well, it must be “completed.” Completion is the process in 

which the well is enabled to produce oil or gas. Once the desired well depth is reached, the 

formation must be tested and evaluated to determine whether the well will be completed for 

production, or plugged and abandoned. To complete the well production, casing is installed and 

cemented and the drilling rig is dismantled and moved to the next site. A service rig is brought 

in to perforate the production casing and run production tubing. If no further pre-production 

servicing is needed, the christmas tree is installed and the production cycle begins. This category 

addresses emissions associated with the completion process at oil and gas wells. 

Emission factors for gas and oil well completions are specified as flaring and venting 

activities. It was assumed that both activities occur during the well completion phase. Flaring 

emission factors for CO and NOx were taken from AP-42 for Industrial Flares (US EPA, 1991). 

It is assumed that flares are smokeless, and thus no PM emissions are expected. There are no 

AP-42 flaring emission factors for SO2 or VOC. The displacement equation will be used to 

calculate those emissions (see Completions discussion in Appendix A sections A.3 and A.4). 

Similarly, VOC emissions from venting activities were calculated using the displacement 

equation. 

Well completion statistics were obtained from a resource known as The Drilling 

Observer, which summarizes well completion data that has been collected and archived by TRC 

(The Drilling Observer, 2007). Included in these statistics are the 24-hour potential test results 

of natural gas, condensate, and casinghead gas flow for each completed oil and gas well. Using 

this information, the daily volume of gas vented and/or flared can be calculated on a per well 

basis. The TRC regulations allow up to 10 days of venting after a well is completed, and then 

flaring must be used (TRC, 2007b). For this study, it is assumed conservatively that venting 

occurs for 10 days and flaring occurs on one day. 

Oil and Gas Well Pneumatic Devices 

Pneumatic devices powered by pressurized natural gas are widely used in the natural gas 

industry as liquid level controllers, pressure regulators, and valve controllers. As part of normal 

operation, pneumatic devices release or bleed natural gas to the atmosphere and, as such, are a 

source of VOC emissions. The extent of the emissions depends largely on the design of the 

device in use (US EPA, 2003). 

No available VOC emission factors for gas-actuated pneumatic pumps used during 

drilling and production activities could be located. However, the WRAP study assumed an 

average fuel usage rate of 5 scf/hr of natural gas used to run a pneumatic pump (WRAP, 2005). 

For oil wells, the average VOC weight percent is 33.20% of the casinghead gas; for gas wells, 

the average VOC weight percent of the dry gas is 8.61% and for condensate gas it is 5.39% 

(GPA, 2004). 

Actual operating oil and gas well counts by county were retrieved from the TRC (TRC, 

2005a; TRC 2005b), yielding total pumps on a county basis. 
2-12 

2.2.2 Onshore Production Sources

Oil and Gas Wellheads 

The wellhead is the part of an oil or gas well that terminates at the surface whether on 

land or offshore, where oil or gas products can be withdrawn. The primary function of the

wellhead is to hold the casings and the production tubing of the well. On top of the wellhead sits

the tubing hanger, from which the production tubing is run. The well christmas tree rests on top 

of the tubing hanger, as well as surface flow-control facilities in preparation for the production 

phase of the well. The wellhead is a source of VOC emissions from various fugitive outlets. 

The AP-42 emission factor used to calculate VOC emissions from oil wellheads is based 

on the number of oil wellheads in place. The TRC collects and maintains oil wellhead counts by 

county in Texas (TRC, 2005a). The AP-42 emission factor for VOC emissions from gas

wellheads is based on gas production. Gas production data by county in Texas is also available 

from the TRC (TRC, 2005c). 

Compressor Engines 

This category concerns gas field compressor engines used to boost the wellhead pressure 

of natural gas so that it can be injected into gathering lines and moved into subsequent 

processing stages of the gas industry. Reciprocating engines, fueled with raw natural gas, are 

normally used to drive gas field compressors. The results of 2005 and 2006 studies of natural 

gas compressor engines by the HARC were applied for this project to generate emission factors 

for engines at oil and gas production facilities (HARC, 2005; HARC, 2006a). Emission factors 

were calculated using the following equation provided in the HARC report: 

EFijk = F1i * F2j * Ci * Hj * EFjk * 1/2000 

Where: 

 EFijk = Emission factor for county i, for engine type j, and pollutant k (tons/MSCF) 

 F1i = Fraction of wells requiring compression in county i 

 F2j = Fraction of compression load represented by engines of type j 

 Ci = Compression requirements for county i (hp-hr/MSCF) 

 Hj = Brake specific fuel consumption for engine type j (MMBtu/hp-hr) 

 EFjk = Emission factor for engine type j, and pollutant k (lb/MMBtu) 

 1/2000 = Conversion from lbs of emissions to tons of emissions 

Although county-specific data are not available for all these variables, the HARC study 

developed compression requirements and compression loads for three distinct districts in eastern 

Texas, including one attainment area and two nonattainment areas (Houston and Dallas). For 

this project, these data were applied to the other Texas counties, according to attainment status, 

to generate county-specific emission factors for compressor engines.

The HARC study assumed the fraction of wells requiring compression is equal to the 

fraction of wells greater than one year old (HARC, 2005). The fraction of wells greater than one 
2-13 

year old was relatively constant in the three districts examined by the HARC study. For this 

inventory project, it was assumed that this fraction remains constant across the entire state for the 

purpose of estimating emissions from compressor engines. 

While the initial report (HARC, 2005) focused on engines less than 500 hp, the follow-up 

report (HARC, 2006a) included engines with greater than 500 hp and also provided a more 

detailed breakdown of engines less than 500 hp. The distribution of engine types presented in 

the 2006 follow-up report was used for this inventory study to estimate the fractions of various 

engine types in attainment and nonattainment areas of Texas. The compression requirements in 

the three districts included in the previous HARC study were relatively consistent. An average 

of these factors was applied to the entire state in both attainment and nonattainment areas. 

The HARC study selected representative engine models for each category of engine and 

used the average fuel consumption for each of those engines to represent the fuel consumption 

for each of those engine types as a whole. For this oil and gas inventory study, the fuel 

consumption data for those same representative engines was used to estimate fuel consumption 

from each engine type. 

Pollutant- and engine-specific emission factors were taken from AP-42 to estimate 

pollutant emissions from each engine type based on the county-by-county breakdown of engine 

use described above. Gas production data, the basis for the emissions estimation equation, were 

obtained from county-specific production data collected by the TRC. 

Dehydrators 

Glycol dehydrators are used by the natural gas industry to remove water from raw natural 

gas to improve its quality for sale, and to help prevent corrosion in downstream pipelines. As the 

dehydrator system removes moisture from the gas, some methane and VOC is also absorbed and 

then lost to the atmosphere in the glycol reboiler process. For this project, uncontrolled VOC 

emissions from dehydrators were estimated using a gas production-based emission factor 

provided by the Wyoming Department of Environmental Quality (WYDEQ) for use in the

WRAP study (WRAP, 2005). The emission factor was applied to Texas county gas production 

figures obtained from the TRC. 

Heater Treaters

Heater treaters are devices used at oil wells to separate oil-water emulsions that are 

present. These devices are found in both horizontal and vertical designs with a firebox on the 

bottom. The units are usually fueled by natural gas or demulsified crude oil. Emissions from the 

fuel combustion process are being estimated in this project. 

Uncontrolled NOX and CO emissions from heater treaters were estimated using the 

emission factors provided by the WYDEQ for use in the WRAP oil and gas sources inventory 

report (WRAP, 2005). The emission factors are based on the quantity of oil produced, and oil 

production data by county was obtained from the TRC (TRC, 2005c). 
2-14 

Oil and Condensate Storage Tanks 

At oil and gas wells, oil and condensate are collected in storage tanks prior to being 

transferred for processing. The storage tanks are sources of VOC emissions from working, 

breathing, and flashing losses. Uncontrolled VOC emissions from oil and condensate storage 

tanks were calculated using emission factors presented for comparison in the study “VOC 

Emissions from Oil and Condensate Storage Tanks” prepared by the HARC in October 2006 

(HARC, 2006b). The emission factors used came from factors developed and published by the

WYDEQ. While the HARC study made emission measurements at 33 tank batteries in three 

geographic areas of Texas and calculated average values, the confidence intervals of the results 

were very large and the averages themselves were considerably higher than established emission 

factors from both Wyoming and Colorado (see WRAP, 2005). Because of this high degree of 

data uncertainty with the HARC study measurements, the WYDEQ emission factors were 

selected as the best choice to estimate VOC emissions for oil and condensate storage tanks. The 

emission factors are applied to county-specific oil and condensate production figures obtained 

from the TRC (TRC, 2005c). 

Oil and Condensate Loading 

Oil and condensate stored in storage tanks is transferred to trucks and railcars for

shipment for further processing. Fugitive VOC emissions are released from these loading 

processes. Emissions from the loading of oil and condensate were estimated using an AP-42 

equation (US EPA, 1995a) and county-specific temperature data for Texas. The AP-42 equation 

to calculate loadout emission factors is: 

LL = 12.46 * S * P * M / T 

Where: 

 LL = Loading loss (lb/1,000 gal of liquid loaded) 

 S = Saturation factor (based on type of loading operation) 

 P = True vapor pressure of liquid loaded (psia) 

 M = Molecular weight of tank vapors (lb/lb-mole) 

 T = Temperature of bulk liquid loaded (oR) 

To determine the saturation factor, the type of loading operation employed throughout the 

state of Texas is assumed to be submerged loading with a dedicated vapor balance (S = 1.00 in 

the equation above). The true vapor pressure of oil and condensate was determined by using 

average temperature data for each county in Texas and temperature-dependent vapor pressures of 

crude oil from AP-42. Temperature data from 87 weather stations throughout Texas were 

obtained and isotherms were developed to estimate average annual temperatures for each county 

in Texas. These temperatures determined both the true vapor pressure using AP-42 data and the 

average temperature of the bulk liquid (T). The molecular weight of tank vapors was assumed 

constant and equal to AP-42 data for crude oil (50 lb/lb-mole) and gasoline (RVP 7) (68 lb/lbmole) at 60°F for oil and condensate, respectively. The gasoline value was used for condensate 

since no specific number for condensate was available. 
2-15 

The AP-42 equation to calculate temperature-dependent emission factors for loadout

losses generates an emission factor based on the amount of liquid loaded (US EPA, 1995a). The 

calculated emission factors were applied to the amount of oil and condensate produced in each 

county, which was obtained from data provided by the TRC (TRC, 2005c). 

Pump and Piping Component Fugitive Losses 

At producing well sites, there are numerous pumps and piping configurations used to 

move oil and gas products and get them into the processing and distribution systems. These 

pieces of equipment contain numerous components such flanges, valves, and seals that are 

potential sources of fugitive VOC emissions. Emissions from these sources were estimated for 

the purposes of this inventory. Fugitive (uncontrolled) emissions from pump and piping 

components were estimated using emission factors developed by the American Petroleum 

Institute (API) in their publication number 4615 (API, 1995). These API emission factors are 

available for connections, flanges, open ends, pumps, valves, and other (including instruments, 

loading arms, pressure relief valves, stuffing boxes, compressor seals, dump lever arms, and 

vents) in units of lb/component-day for both gas and oil service. The API factors were 

developed for THC emissions. Therefore, the THC factors were multiplied by the average 

weight fraction of VOCs in onshore light crude and onshore gas production (0.292 and 0.035, 

respectively) to obtain the VOC emission factors used in the inventory. 

The API emission factors for fugitive VOC emissions from pump and piping components 

are on a “per component” basis. In order to apply these “per component” factors on a county 

basis, average equipment counts for oil and gas facilities were obtained. The most complete and 

descriptive information found on component counts came from a study conducted by the 

Canadian Association of Petroleum Producers (CAPP, 1999). These data provide the numbers of 

valves, connectors, pressure relief valves and open-ended lines in both gas and liquid service at a 

typical battery. According to the results of the 33 batteries surveyed for HARC’s study of “VOC 

Emissions from Oil and Condensate Storage Tanks” (HARC, 2006b) and HARC’s “Natural Gas 

Compressor Engine Survey for Gas Production and Processing Facilities” (HARC, 2005), the 

average number of wellheads served per battery is 2.8. These factors were used in conjunction 

with county wellhead data to estimate fugitive emissions from pump and piping components. 

Coal Bed Methane Sources 

 Emissions from coalbed methane (CBM) pumps were on the initial source category list 

considered for this inventory. CBM is natural gas that can be extracted from coal seams, and is 

high in methane content. Emissions occur from pumping the water from the well (or dewatering 

the coal seam) using small pumps. CBM production is a major natural gas source in some 

western states, such as Wyoming, Colorado, and New Mexico. In 2001, the first CBM field in 

Texas was discovered in the Sacatosa (Olmos) Field in Maverick County, TX. From 2001 to 

2004, attempts were made by The Texas Exploration Company (TXCO) to have CBM be a 

viable, economic option for natural gas production (TXCO, 2004). Nearly 50 wells were drilled 

during that time. However, TXCO sold their CBM operations to Encana in 2005, and it is 

believed that CBM production was halted for 2005. Thus, no emission estimates were developed 

for CBM pumps for the Maverick County site for 2005. 
2-16 

2.2.3 Offshore Production Sources

This category addresses emissions from oil and gas platforms in state and federal waters 

off the coast of Texas. State waters are defined to be the area lying 0 – 10 miles from shore, 

while federal waters are the area >10 – 25 miles from shore. For the state waters area, 

exploration and production sources are addressed, while in federal waters only production source 

emissions are inventoried. Emission estimates for these sources were determined in several 

ways. Emission estimates for the federal waters sources were obtained directly from the 2005 

draft emission inventory for oil and gas platforms in the Gulf of Mexico produced by MMS 

(MMS, 2007). As of August 2007, the MMS inventory data and report are considered draft, and 

while MMS is allowing the emission estimate data to be used for the purposes of this TCEQ 

project, no data are to be published, cited, quoted, or released outside of TCEQ until such time 

that MMS publishes the 2005 results as final. 

State waters estimates were derived by a combination of approaches. The TCEQ 

industrial point source group supplied emission estimate data for five production platforms in 

state waters. Other information on the number and locations of additional platforms in state 

waters was developed from TRC data and data provided by the TCEQ Project Representative. 

The five platforms provided by TCEQ represent a portion of the total facilities operating 

in Texas state waters. Based on production information, characteristics, and fuel consumption 

(as outlined in Appendix C.2), it is estimated that there are 17 oil platforms and 18 natural gas 

platforms operating in Texas state waters. To calculate emissions for all platforms operating in 

Texas state waters, a model platform with typical equipment types and counts was developed. 

Operating parameters for the model platform equipment types were developed using data from 

the 2005 MMS dataset (i.e., platforms included in the MMS 2005 inventory of platforms in 

federal waters). Information on typical hours of operation, fuel input rate, fuel usage rate, and 

fuel type were used to develop combustion source profiles. Other information, such as drilling 

days, barge loading of oil, and total oil and condensate produced were obtained from the TRC

website and used to model evaporative losses. Once the model platform was developed, it was 

applied to the estimated number of platforms to generate total state waters activity. The total 

activity data was then apportioned to the appropriate offshore county via oil and gas production 

for 2005. 
3-1 

3.0 SUMMARY OF 2005 BASE YEAR EMISSIONS 

This section of the project report presents summarized results of the Texas area source oil 

and gas emission inventory development effort. Emission inventory estimates are presented on 

both statewide and county-specific bases according to the previously identified groupings of 

onshore exploration sources, onshore production sources, and offshore production sources 

(Section 3.1). In addition to presenting the inventory results, discussion is provided on the 

strengths and weaknesses of the inventory, inventory uncertainties, and possible improvements 

that can be made to the emission estimates. Section 3.2 describes how the various individual 

source categories compare and rank relative to each other for each of the estimated pollutants. 

Section 3.3 provides input on the level of emissions per county and what counties represent the 

largest share of statewide emissions. In Section 3.4, emissions are examined in terms of county 

attainment/nonattainment designations. The distribution of emissions by designation is 

presented. 

3.1 Oil and Gas Emissions Summary 

For the 2005 base year, emission estimates were prepared on both an annual and ozone 

season daily (OSD) basis. The specific details on how each category’s emissions were 

calculated can be found in Appendix A (for onshore exploration sources), Appendix B (for 

onshore production sources), and Appendix C (for offshore production sources). Any required 

derivations of activity or emission factor data are explained, and all data used for the derivations 

are shown. All applied equations are presented and discussed, and every variable, constant, and 

conversion factor used is defined and documented. Each source appendix section presents 

emission estimates (in tabular form) on an SCC basis for every applicable county in the state. 

All of these individual emissions data are summed to provide the tables in Section 3.0. 

Electronic Excel® spreadsheet files are provided along with this hard copy report that mimic all

of the information in the documentation appendices. 

Table 3-1 presents a summary of annual statewide criteria pollutant emissions from 

individual area source oil and gas categories. Table 3-2 presents the same statewide information, 

but for emissions on an OSD basis as opposed to annual. The emissions data in Tables 3-1 and 

3-2 are organized by the exploration, production, and offshore (divided into state and federal 

waters) groupings. As shown in Table 3-1, the largest amount of CO emissions (70.6%) comes 

from onshore production sources (primarily from natural gas compressor engines). Emissions of 

NOx are dominated by onshore exploration (54.2%) and onshore production sources (41.6%). 

Drilling rig engines are the most significant NOx exploration category, while compressor engines 

are the major production-related NOx source. 

For VOC emissions, onshore production sources make up 85.1% of the total VOC and 

onshore exploration sources at 14.3%. The chief production sources contributing to VOC are 

glycol dehydrators (26.9%), condensate storage tanks (22.9%), and gas wellheads (12.6%). The 

onshore exploration grouping, namely drilling rig engines, constitute 98.4% of SO2 emissions. 

Drilling rig engines (onshore exploration) and compressor engines (onshore production) together 

are responsible for roughly 96.4% of PM (PM10 and PM2.5) emissions. The source category 

contributions are summarized by pollutant in Table 3-3. 
3-2 

Table 3-1. Summary of Annual Statewide Criteria Pollutant Emissions 

Annual Emissions (tons/yr) 

Oil and Gas Emission Sources CO NOX PM10 PM2.5 SO2 VOC 

Onshore Exploration 

Drilling Rig Engines 27,442 119,647 1,998 1,954 13,697 3,183 

Mud Degassing -- -- -- -- -- 10,674 

Pneumatic Pumps-Gas Wells -- -- -- -- -- 73,474 

Pneumatic Pumps-Oil Wells -- -- -- -- -- 19,764 

Well Completions: Gas Wells 2,180 401 -- -- -- 19,764 

Well Completions: Oil Wells 74 14 -- -- 138 13,145 

Onshore Exploration Total 29,695 120,061 1,998 1,954 13,835 120,240 

 

Onshore Production 

Fugitives - All Components -- -- -- -- -- 42,652 

Glycol Dehydrators -- -- -- -- -- 225,860 

Heater Treater 195 977 -- -- -- -- 

Loading: Truck/Railcar - Condensate -- -- -- -- -- 6,188 

Loading: Truck/Railcar - Oil -- -- -- -- -- 26,691 

Natural Gas Compressor Engines: All 

types 88,754 91,021 1,578 1,578 44 5,058 

Storage Tanks - Condensate -- -- -- -- -- 192,744 

Storage Tanks - Crude Oil -- -- -- -- -- 76,552 

Wellheads - Gas Production -- -- -- -- -- 105,881 

Wellheads - Oil Production -- -- -- -- -- 34,315 

Onshore Production Total 88,949 91,998 1,578 1,578 44 715,941 

 

Offshore-State Waters (0-10 miles from TX coast) 

Boilers/Heaters 14 16 0.3 0.3 0.1 1 

Cold Vents -- -- -- -- -- 986 

Diesel Engines 217 1,006 71 71 78 75 

Drilling Rig Engines 123 537 9 9 61 14 

Flares 614 114 <0.1 <0.1 1 10 

Fugitives - All Components -- -- -- -- -- 520 

Glycol Dehydrators -- -- -- -- -- 189 

Loading: Barge – Oil -- -- -- -- -- 1 

Mud Degassing -- -- -- -- -- 70 

Natural Gas Compressor Engines: All 

types 861 847 11 11 0.4 25 

Natural Gas Turbines 851 3,321 20 20 36 22 

Pneumatic Pumps-Gas and Oil Wells -- -- -- -- -- 29 

Pressure/Level Controllers -- -- -- -- -- 1 

Storage Tanks - Condensate -- -- -- -- -- 1,982 

Storage Tanks - Crude Oil -- -- -- -- -- 99 

Offshore-State Waters Total 2,680 5,841 110 110 177 4,025 

 
3-3 

Table 3-1. Summary of Annual Statewide Criteria Pollutant Emissions (Continued) 

Annual Emissions (tons/yr)

Oil and Gas Emission Sources CO NOX PM10 PM2.5 SO2 VOC 

Offshore-Federal Waters (within 10-25 miles of TX coast) 

Boilers/Heaters 5 6 0.1 0.1 <0.1 0.3 

Cold Vents -- -- -- -- -- 155 

Diesel Engines 32 141 8 8 6 9 

Fugitives - All components -- -- -- -- -- 667 

Glycol Dehydrators -- -- -- -- -- 43 

Natural Gas Compressor Engines: All 

types 4,585 3,225 16 16 1 87 

Natural Gas Turbines 22 86 1 1 0.2 1 

Pneumatic Pumps-Gas and Oil Wells -- -- -- -- -- 63 

Pressure/Level Controllers -- -- -- -- -- 25 

Storage Tanks - Condensate -- -- -- -- -- 1 

Storage Tanks - Crude Oil -- -- -- -- -- 37 

Storage Tanks - Flashing Losses -- -- -- -- -- 0.1 

Offshore-Federal Waters Total 4,644 3,457 25 25 7 1,088 

 

Grand Total - All Sources 125,968 221,357 3,711 3,667 14,064 841,295
3-4 

Table 3-2. Summary of Ozone Season Daily (OSD) Statewide Criteria Pollutant Emissions 

Ozone Season Daily (tons/day) 

Oil and Gas Emission Sources CO NOX PM10 PM2.5 SO2 VOC 

Onshore Exploration 

Drilling Rig Engines 74.82 326.21 5.45 5.33 37.34 8.68 

Mud Degassing -- -- -- -- -- 29.10 

Pneumatic Pumps-Gas Wells -- -- -- -- -- 200.21 

Pneumatic Pumps-Oil Wells -- -- -- -- -- 182.12 

Well Completions: Gas Wells 5.94 1.09 -- -- -- 53.88 

Well Completions: Oil Wells 0.20 0.04 -- -- 0.38 35.81 

Onshore Exploration Total 80.96 327.33 5.45 5.33 37.72 327.88 

 

Onshore Production 

Fugitives - All Components -- -- -- -- -- 116.22 

Glycol Dehydrators -- -- -- -- -- 615.51 

Heater Treater 0.53 2.66 -- -- -- -- 

Loading: Truck/Railcar - Condensate -- -- -- -- -- 16.86 

Loading: Truck/Railcar – Oil -- -- -- -- -- 72.71 

Natural Gas Compressor Engines: All 

types 241.88 248.06 4.30 4.30 0.12 13.78 

Storage Tanks – Condensate -- -- -- -- -- 525.27 

Storage Tanks - Crude Oil -- -- -- -- -- 208.54 

Wellheads - Gas Production -- -- -- -- -- 288.55 

Wellheads - Oil Production -- -- -- -- -- 93.50 

Onshore Production Total 242.41 250.72 4.30 4.30 0.12 1,950.95 

 

Offshore-State Waters (0-10 miles from TX coast) 

Boilers/Heaters 0.04 0.04 <0.01 <0.01 <0.01 <0.01 

Cold Vents -- -- -- -- -- 2.68 

Diesel Engines 0.59 2.74 0.19 0.19 0.21 0.20 

Drilling Rig Engines 0.34 1.46 0.02 0.02 0.17 0.04 

Flares 1.67 0.31 <0.01 <0.01 <0.01 0.03 

Fugitives - All Components -- -- -- -- -- 1.42 

Glycol Dehydrators -- -- -- -- -- 0.52 

Loading: Barge – Oil -- -- -- -- -- <0.01 

Mud Degassing -- -- -- -- -- 0.19 

Natural Gas Compressor Engines: All 

types 2.35 2.30 0.03 0.03 <0.01 0.07 

Natural Gas Turbines 2.32 9.04 0.05 0.05 0.10 0.06 

Pneumatic Pumps-Gas and Oil Wells -- -- -- -- -- 0.08 

Pressure/Level Controllers -- -- -- -- -- <0.01 

Storage Tanks – Condensate -- -- -- -- -- 5.40 

Storage Tanks - Crude Oil -- -- -- -- -- 0.27 

Offshore-State Waters Total 7.30 15.90 0.30 0.30 0.48 10.95 

 
3-5 

Table 3-2. Summary of Ozone Season Daily (OSD) Statewide Criteria 

Pollutant Emissions (Continued) 

Ozone Season Daily (tons/day) 

Oil and Gas Emission Sources CO NOX PM10 PM2.5 SO2 VOC 

Offshore-Federal Waters (within 10-25 miles of TX coast) 

Boilers/Heaters 0.01 0.02 <0.01 <0.01 <0.01 <0.01 

Cold Vents -- -- -- -- -- 0.42 

Diesel Engines 0.09 0.38 0.02 0.02 0.02 0.02 

Fugitives - All components -- -- -- -- -- 1.82 

Glycol Dehydrators -- -- -- -- -- 0.12 

Natural Gas Compressor Engines: All 

types 12.49 8.78 0.04 0.04 <0.01 0.24 

Natural Gas Turbines 0.06 0.23 <0.01 <0.01 <0.01 <0.01 

Pneumatic Pumps-Gas and Oil Wells -- -- -- -- -- 0.17 

Pressure/Level Controllers -- -- -- -- -- 0.07 

Storage Tanks – Condensate -- -- -- -- -- <0.01 

Storage Tanks - Crude Oil -- -- -- -- -- 0.10 

Storage Tanks - Flashing Losses -- -- -- -- -- <0.01 

Offshore-Federal Waters Total 12.65 9.41 0.07 0.07 0.02 2.96 

 

Grand Total - All Sources 343.31 603.37 10.11 9.99 38.34 2,292.55 
3

-6

Table 3-3. Summary of Oil and Gas Category Emission Contribution Rankings by Pollu

CO Emissions 

Contributions 

NOx Emissions 

Contributions 

VOC Emissions 

Contributions 

PM10 Emissions 

Contributions 

PM2.5 Emissio

Contribution

Compressor Engines (OP) – 70.5% 

Drilling Rig Engines (OE) – 54.1% 

Glycol Dehydrators (OP) – 26.9% 

Drilling Rig Engines (OE) - 53.8% 

Drilling Rig Engi(OE) - 53.3% 

Drilling Rig Engines (OE) – 21.8% 

Compressor Engines (OP) – 41.2% 

Condensate Storage Tanks (OP) – 22.9% 

Compressor Engines (OP) – 42.5% 

Compressor Engi(OP) – 43% 

Gas Well Completions (OE) – 1.7% 

Natural Gas Turbines (OSW) – 1.5% 

Gas Wellheads (OP) – 12.6% 

Diesel Engines (OSW) – 1.9% 

Diesel Engines (OSW) – 1.9% 

All others - <1% each Compressor Engines (OFW) – 1.5% Crude Oil Storage Tanks (OP) – 9.1% All others - <1% each All others - <1% 

All others - <1% each 

Gas & Oil Well Pneumatic Devices (OE) – 8.7% Pump & Piping Fugitives (OP) – 5.1% Oil Wellheads (OP) – 4.1% Oil Loading (OP) – 3.2% Gas Well Completions (OE) – 2.4% Oil Well Completions (OE) – 1.6% Mud Degassing (OE) – 1.3% 

All others - <1% each 

OE = Onshore Exploration OP = Onshore Production OSW = Offshore State Waters OFW = Offshore Federal Waters 
3-7 

Tables 3-4a, 3-4b, and 3-4c provide a view of criteria pollutant emissions at the 

individual county level. Table 3-4a lists annual and OSD emissions estimates collectively for all 

onshore exploration sources. The county level estimates for each specific exploration category 

are detailed in Appendix A. Similarly, Tables 3-4b and 3-4c present county level estimates for 

onshore production and offshore production categories, respectively. Appendix B provides 

county-specific estimates and documentation for all onshore production categories. Emissions 

from offshore production sources in state and federal waters are addressed by county and lease 

block in Appendix C. 

One of the greatest uncertainties regarding the emissions inventory has to be the potential 

existence of emission controls at onshore sources. Attempts to gather input on the likelihood and 

extent of controls did not yield much information. Since many of these operations would be 

covered by the TCEQ permit-by-rule program, calls were made to these contacts to try and 

determine if there was any state data on the extent of controls. Essentially no useful information 

in regards to controls could be identified. Within the resource constraints of this project, it was 

not feasible to conduct an investigation into this specific issue. As described in the previous 

Task 2 Technical Memorandum, essentially all of the onshore exploration and production source 

estimates reflect uncontrolled emissions. This is particularly important for two of the categories 

found to be prominent VOC emitters – glycol dehydrators and condensate storage tanks. If a 

significant number of these units do have VOC controls, the estimated inventory results for VOC 

would be impacted. In addition to the permit-by-rule for oil and gas sources, a specific TCEQ 

rule (Rule §115.112) is in effect for VOC storage. That rule applies to oil and condensate 

storage on a per tank/tank battery basis based on total throughput. Since this category was 

addressed as an area source for this inventory, determining the rule applicability for all of the 

tanks/tank batteries in Texas was beyond the resources and feasibility of this project. Additional 

investigation would be needed to estimate tank/tank battery throughputs such that possible rule 

applicability and control impacts could be assessed. 

As with any inventory development process, assumptions and concessions have to be 

made because of lack of data and time and resource limitations. The estimation procedures used 

in this inventory were detailed in the previous Task 2 Technical Memorandum and approved by 

TCEQ. These procedures represent sound and valid estimation techniques; however, if future 

improvements could be made, the overall quality of the resulting emission estimates could be 

improved. Some of these possible improvements are listed below. 

Drilling Rig Engines: develop data on actual fuel usage and/or rig horsepower sizes. If 

these data are too cumbersome to obtain, then get the actual number of drilling days. 

These data should eventually be available from the TRC. However, it should be noted 

that the drilling profile days profiles approach used in the inventory represents a much 

more accurate level of drilling than just using an arbitrary number (e.g., like 15 days per 

10,000 feet). 
3

-8

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Explor

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Anderson/48001 45.3 0.123 196.6 0.535 3.3 0.009 3.2 0.009 22.5 0Andrews/48003 72.2 0.197 307.3 0.837 5.1 0.014 5.0 0.014 38.5 0Angelina/48005 24.0 0.065 97.0 0.264 1.6 0.004 1.6 0.004 11.1 0Aransas/48007 5.1 0.014 19.8 0.054 0.3 0.001 0.3 0.001 2.8 0Archer/48009 35.8 0.097 156.0 0.425 2.6 0.007 2.5 0.007 17.9 0Armstrong/48011 Atascosa/48013 23.7 0.065 102.3 0.279 1.7 0.005 1.7 0.005 11.7 0Austin/48015 24.3 0.066 93.8 0.256 1.6 0.004 1.5 0.004 11.2 0Bailey/48017 Bandera/48019 Bastrop/48021 Baylor/48023 3.7 0.010 16.0 0.044 0.3 0.001 0.3 0.001 1.8 0Bee/48025 196.6 0.535 814.4 2.218 13.6 0.037 13.3 0.036 93.0 0Bell/48027 Bexar/48029 Blanco/48031 Borden/48033 35.0 0.095 151.9 0.414 2.5 0.007 2.5 0.007 17.7 0Bosque/48035 3.2 0.009 13.9 0.038 0.2 0.001 0.2 0.001 1.6 0Bowie/48037 2.3 0.006 10.0 0.027 0.2 0.000 0.2 0.000 1.2 0Brazoria/48039 161.1 0.439 666.3 1.817 11.1 0.030 10.9 0.030 76.5 0Brazos/48041 41.9 0.114 170.2 0.463 2.8 0.008 2.8 0.008 21.7 0Brewster/48043 Briscoe/48045 Brooks/48047 188.7 0.514 727.4 1.981 12.1 0.033 11.8 0.032 83.6 0Brown/48049 4.6 0.012 19.8 0.054 0.3 0.001 0.3 0.001 2.3 0Burleson/48051 29.7 0.081 121.8 0.332 2.0 0.006 2.0 0.005 17.3 0Burnet/48053 Caldwell/48055 27.2 0.074 118.8 0.324 2.0 0.005 1.9 0.005 13.6 0Calhoun/48057 59.8 0.163 244.0 0.665 4.1 0.011 4.0 0.011 27.9 0Callahan/48059 2.5 0.007 10.6 0.029 0.2 0.000 0.2 0.000 1.3 0
3

-9

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissi

Exploration Sources (Cont.) 

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Cameron/48061 Camp/48063 Carson/48065 1.1 0.003 4.0 0.011 0.1 0.000 0.1 0.000 0.5 0Cass/48067 5.5 0.015 21.6 0.059 0.4 0.001 0.4 0.001 2.5 0Castro/48069 Chambers/48071 45.2 0.123 161.4 0.440 2.7 0.007 2.6 0.007 20.5 0Cherokee/48073 88.8 0.242 356.3 0.970 5.9 0.016 5.8 0.016 40.7 0Childress/48075 Clay/48077 11.8 0.032 51.3 0.140 0.9 0.002 0.8 0.002 6.0 0Cochran/48079 12.6 0.034 54.4 0.148 0.9 0.002 0.9 0.002 6.4 0Coke/48081 12.8 0.035 55.0 0.150 0.9 0.002 0.9 0.002 6.7 0Coleman/48083 1.2 0.003 5.0 0.013 0.1 0.000 0.1 0.000 0.6 0Collin/48085 Collingsworth/48087 Colorado/48089 163.2 0.444 674.5 1.837 11.2 0.031 11.0 0.030 77.0 0Comal/48091 Comanche/48093 0.5 0.001 2.3 0.006 0.0 0.000 0.0 0.000 0.3 0Concho/48095 29.3 0.080 118.7 0.323 2.0 0.005 1.9 0.005 13.7 0Cooke/48097 175.1 0.477 759.9 2.070 12.7 0.035 12.4 0.034 87.4 0Coryell/48099 Cottle/48101 37.0 0.101 154.3 0.420 2.6 0.007 2.5 0.007 17.6 0Crane/48103 51.2 0.139 204.4 0.557 3.4 0.009 3.3 0.009 25.0 0Crockett/48105 745.2 2.029 2987.0 8.135 49.7 0.135 48.6 0.132 343.9 0Crosby/48107 Culberson/48109 4.7 0.013 20.4 0.055 0.3 0.001 0.3 0.001 2.3 0Dallam/48111 Dallas/48113 Dawson/48115 18.9 0.051 81.6 0.222 1.4 0.004 1.3 0.004 9.7 0Deaf Smith/48117 
3

-10

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissi

Exploration Sources (Cont.) 

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Delta/48119 Denton/48121 731.4 1.992 2829.9 7.707 47.0 0.128 46.0 0.125 322.5 0De Witt/48123 199.1 0.542 791.5 2.155 13.2 0.036 12.9 0.035 90.3 0Dickens/48125 12.0 0.033 51.7 0.141 0.9 0.002 0.8 0.002 6.1 0Dimmit/48127 53.1 0.145 213.1 0.580 3.5 0.010 3.5 0.009 25.2 0Donley/48129 Duval/48131 173.7 0.473 658.9 1.794 10.9 0.030 10.7 0.029 75.4 0Eastland/48133 37.1 0.101 160.5 0.437 2.7 0.007 2.6 0.007 18.5 0Ector/48135 202.3 0.551 877.7 2.390 14.7 0.040 14.3 0.039 102.3 0Edwards/48137 30.5 0.083 124.6 0.339 2.1 0.006 2.0 0.006 14.2 0Ellis/48139 2.5 0.007 9.6 0.026 0.2 0.000 0.2 0.000 1.1 0El Paso/48141 Erath/48143 8.5 0.023 32.4 0.088 0.5 0.001 0.5 0.001 3.8 0Falls/48145 2.7 0.007 11.7 0.032 0.2 0.001 0.2 0.001 1.3 0Fannin/48147 Fayette/48149 41.6 0.113 177.6 0.484 3.0 0.008 2.9 0.008 21.7 0Fisher/48151 3.5 0.010 14.9 0.041 0.2 0.001 0.2 0.001 2.0 0Floyd/48153 3.2 0.009 13.7 0.037 0.2 0.001 0.2 0.001 1.6 0Foard/48155 3.6 0.010 14.4 0.039 0.2 0.001 0.2 0.001 1.6 0Fort Bend/48157 107.4 0.293 417.7 1.139 6.9 0.019 6.8 0.019 47.9 0Franklin/48159 27.9 0.076 118.8 0.323 2.0 0.005 1.9 0.005 14.3 0Freestone/48161 616.0 1.677 2464.5 6.712 41.0 0.112 40.1 0.109 281.0 0Frio/48163 6.3 0.017 27.3 0.074 0.5 0.001 0.4 0.001 3.1 0Gaines/48165 405.9 1.105 1752.2 4.772 29.2 0.080 28.6 0.078 202.4 0Galveston/48167 19.5 0.053 78.6 0.214 1.3 0.004 1.3 0.003 9.6 0Garza/48169 40.7 0.111 177.3 0.483 3.0 0.008 2.9 0.008 20.3 0Gillespie/48171 Glasscock/48173 26.0 0.071 109.3 0.298 1.8 0.005 1.8 0.005 14.0 0Goliad/48175 444.1 1.209 1667.8 4.542 27.7 0.075 27.0 0.074 189.9 0
3

-11

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissi

Exploration Sources (Cont.) 

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Gonzales/48177 6.4 0.018 28.1 0.077 0.5 0.001 0.5 0.001 3.2 0Gray/48179 8.5 0.023 32.1 0.087 0.5 0.001 0.5 0.001 3.7 0Grayson/48181 88.8 0.242 382.6 1.042 6.4 0.017 6.2 0.017 45.8 0Gregg/48183 126.7 0.350 446.7 1.233 7.4 0.020 7.2 0.020 50.7 0Grimes/48185 86.9 0.237 270.9 0.738 4.4 0.012 4.3 0.012 30.5 0Guadalupe/48187 11.8 0.032 51.5 0.140 0.9 0.002 0.8 0.002 5.9 0Hale/48189 7.7 0.021 32.8 0.089 0.5 0.001 0.5 0.001 4.1 0Hall/48191 Hamilton/48193 0.7 0.002 3.0 0.008 0.1 0.000 0.0 0.000 0.3 0Hansford/48195 41.9 0.114 170.4 0.464 2.8 0.008 2.8 0.008 19.4 0Hardeman/48197 59.6 0.162 259.5 0.707 4.3 0.012 4.2 0.012 29.9 0Hardin/48199 59.7 0.162 238.3 0.648 4.0 0.011 3.9 0.011 28.5 0Harris/48201 61.8 0.169 261.7 0.714 4.4 0.012 4.3 0.012 30.0 0Harrison/48203 626.3 1.728 2538.1 7.004 42.2 0.117 41.3 0.114 293.6 0Hartley/48205 10.2 0.028 42.0 0.114 0.7 0.002 0.7 0.002 4.8 0Haskell/48207 0.7 0.002 3.0 0.008 0.0 0.000 0.0 0.000 0.3 0Hays/48209 Hemphill/48211 3534.0 9.624 15159.2 41.283 252.9 0.689 247.4 0.674 1739.0 4Henderson/48213 30.6 0.083 115.5 0.315 1.9 0.005 1.9 0.005 13.2 0Hidalgo/48215 411.0 1.119 1531.2 4.170 25.4 0.069 24.8 0.068 174.0 0Hill/48217 67.7 0.184 293.4 0.799 4.9 0.013 4.8 0.013 33.6 0Hockley/48219 86.5 0.236 371.2 1.011 6.2 0.017 6.1 0.016 45.2 0Hood/48221 48.0 0.131 171.9 0.468 2.8 0.008 2.8 0.008 19.5 0Hopkins/48223 1.8 0.005 7.7 0.021 0.1 0.000 0.1 0.000 0.9 0Houston/48225 68.9 0.188 255.0 0.694 4.2 0.012 4.1 0.011 29.0 0Howard/48227 21.9 0.060 92.8 0.253 1.5 0.004 1.5 0.004 11.9 0Hudspeth/48229 Hunt/48231 Hutchinson/48233 24.1 0.066 99.4 0.271 1.7 0.005 1.6 0.004 11.3 0
3

-12

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissi

Exploration Sources (Cont.) 

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Irion/48235 218.9 0.596 939.1 2.557 15.7 0.043 15.3 0.042 108.5 0Jack/48237 102.4 0.279 425.0 1.157 7.1 0.019 6.9 0.019 49.3 0Jackson/48239 63.1 0.172 216.8 0.591 3.6 0.010 3.5 0.010 25.3 0Jasper/48241 5.3 0.014 16.0 0.043 0.3 0.001 0.3 0.001 3.3 0Jeff Davis/48243 Jefferson/48245 90.2 0.245 333.2 0.905 5.5 0.015 5.4 0.015 38.8 0Jim Hogg/48247 211.8 0.577 874.6 2.382 14.6 0.040 14.2 0.039 100.0 0Jim Wells/48249 19.5 0.053 78.2 0.213 1.3 0.004 1.3 0.003 9.0 0Johnson/48251 309.2 0.840 979.3 2.661 16.1 0.044 15.7 0.043 110.3 0Jones/48253 12.2 0.033 51.8 0.141 0.9 0.002 0.8 0.002 6.4 0Karnes/48255 33.3 0.091 134.0 0.365 2.2 0.006 2.2 0.006 15.9 0Kaufman/48257 Kendall/48259 Kenedy/48261 159.4 0.434 621.3 1.692 10.3 0.028 10.1 0.027 70.8 0Kent/48263 2.7 0.007 11.8 0.032 0.2 0.001 0.2 0.001 1.4 0Kerr/48265 Kimble/48267 2.4 0.006 9.1 0.025 0.2 0.000 0.1 0.000 1.0 0King/48269 15.8 0.043 68.2 0.186 1.1 0.003 1.1 0.003 7.9 0Kinney/48271 Kleberg/48273 58.4 0.159 223.4 0.608 3.7 0.010 3.6 0.010 25.4 0Knox/48275 0.9 0.002 3.8 0.010 0.1 0.000 0.1 0.000 0.4 0Lamar/48277 Lamb/48279 0.0 0.000 0.0 0.000 0.0 0Lampasas/48281 0.4 0.001 1.7 0.005 0.0 0.000 0.0 0.000 0.2 0La Salle/48283 563.4 1.534 2420.9 6.593 40.4 0.110 39.5 0.108 277.4 0Lavaca/48285 170.2 0.464 644.0 1.754 10.7 0.029 10.4 0.028 73.2 0Lee/48287 56.0 0.153 221.2 0.602 3.7 0.010 3.6 0.010 34.5 0Leon/48289 527.8 1.437 2188.1 5.959 36.5 0.099 35.7 0.097 250.0 0Liberty/48291 180.7 0.493 673.5 1.837 11.2 0.030 10.9 0.030 77.2 0
3

-13

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissi

Exploration Sources (Cont.) 

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Limestone/48293 273.9 0.746 1095.0 2.982 18.2 0.050 17.8 0.049 124.8 0Lipscomb/48295 200.6 0.546 745.3 2.030 12.4 0.034 12.1 0.033 88.1 0Live Oak/48297 492.2 1.340 2107.6 5.740 35.2 0.096 34.4 0.094 241.3 0Llano/48299 Loving/48301 292.7 0.797 1114.0 3.034 18.5 0.050 18.1 0.049 126.8 0Lubbock/48303 7.9 0.021 34.3 0.093 0.6 0.002 0.6 0.002 3.9 0Lynn/48305 6.3 0.017 27.3 0.074 0.5 0.001 0.4 0.001 3.2 0McCulloch/48307 8.0 0.022 34.7 0.094 0.6 0.002 0.6 0.002 4.0 0McLennan/48309 McMullen/48311 333.6 0.909 1283.0 3.494 21.3 0.058 20.8 0.057 146.6 0Madison/48313 30.5 0.083 130.6 0.356 2.2 0.006 2.1 0.006 15.9 0Marion/48315 23.6 0.064 95.2 0.259 1.6 0.004 1.5 0.004 11.3 0Martin/48317 120.0 0.327 520.3 1.417 8.7 0.024 8.5 0.023 60.9 0Mason/48319 Matagorda/48321 151.9 0.414 559.9 1.525 9.3 0.025 9.1 0.025 64.9 0Maverick/48323 147.8 0.403 642.4 1.749 10.7 0.029 10.5 0.029 74.3 0Medina/48325 1.2 0.003 5.1 0.014 0.1 0.000 0.1 0.000 0.6 0Menard/48327 2.5 0.007 10.9 0.030 0.2 0.000 0.2 0.000 1.2 0Midland/48329 266.3 0.725 1151.9 3.137 19.2 0.052 18.8 0.051 134.8 0Milam/48331 4.2 0.011 18.1 0.049 0.3 0.001 0.3 0.001 2.1 0Mills/48333 12.1 0.033 52.7 0.144 0.9 0.002 0.9 0.002 6.0 0Mitchell/48335 24.1 0.066 104.8 0.285 1.8 0.005 1.7 0.005 12.1 0Montague/48337 107.8 0.294 465.5 1.268 7.8 0.021 7.6 0.021 55.0 0Montgomery/48339 37.6 0.103 160.2 0.437 2.7 0.007 2.6 0.007 18.3 0Moore/48341 17.7 0.048 71.6 0.195 1.2 0.003 1.2 0.003 8.3 0Morris/48343 Motley/48345 Nacogdoches/48347 257.8 0.702 920.3 2.506 15.2 0.041 14.9 0.041 104.3 0Navarro/48349 13.8 0.038 58.2 0.159 1.0 0.003 0.9 0.003 6.8 0
3

-14

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissi

Exploration Sources (Cont.) 

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Newton/48351 40.5 0.110 170.4 0.464 2.8 0.008 2.8 0.008 21.8 0Nolan/48353 15.3 0.042 66.3 0.181 1.1 0.003 1.1 0.003 7.8 0Nueces/48355 194.6 0.531 795.7 2.169 13.2 0.036 13.0 0.035 91.4 0Ochiltree/48357 56.6 0.154 213.7 0.582 3.5 0.010 3.5 0.009 25.0 0Oldham/48359 0.1 0.000 0.0 0.000 Orange/48361 32.8 0.089 143.1 0.389 2.4 0.006 2.3 0.006 16.4 0Palo Pinto/48363 21.8 0.059 75.8 0.206 1.3 0.003 1.2 0.003 9.3 0Panola/48365 704.9 1.920 2710.8 7.382 45.0 0.123 44.0 0.120 311.8 0Parker/48367 175.8 0.478 712.6 1.936 11.9 0.032 11.6 0.032 82.4 0Parmer/48369 Pecos/48371 204.8 0.558 813.3 2.215 13.5 0.037 13.2 0.036 93.3 0Polk/48373 36.6 0.100 147.9 0.403 2.5 0.007 2.4 0.007 16.9 0Potter/48375 37.8 0.103 155.9 0.425 2.6 0.007 2.5 0.007 17.8 0Presidio/48377 Rains/48379 Randall/48381 Reagan/48383 493.0 1.343 2140.0 5.828 35.7 0.097 34.9 0.095 248.2 0Real/48385 0.4 0.001 1.6 0.004 0.0 0.000 0.0 0.000 0.2 0Red River/48387 Reeves/48389 77.4 0.211 330.0 0.899 5.5 0.015 5.4 0.015 38.1 0Refugio/48391 68.3 0.186 260.3 0.709 4.3 0.012 4.2 0.012 34.1 0Roberts/48393 168.5 0.459 651.2 1.773 10.8 0.029 10.6 0.029 77.7 0Robertson/48395 583.5 1.589 2352.5 6.407 39.1 0.107 38.3 0.104 268.4 0Rockwall/48397 Runnels/48399 36.4 0.099 156.4 0.426 2.6 0.007 2.6 0.007 18.9 0Rusk/48401 440.7 1.216 1682.5 4.643 27.9 0.077 27.3 0.075 191.4 0Sabine/48403 2.8 0.008 12.1 0.033 0.2 0.001 0.2 0.001 1.4 0San Augustine/48405 San Jacinto/48407 29.0 0.079 118.1 0.322 2.0 0.005 1.9 0.005 13.5 0
3

-15

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissi

Exploration Sources (Cont.) 

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

San Patricio/48409 183.0 0.499 767.7 2.093 12.8 0.035 12.5 0.034 87.7 0San Saba/48411 Schleicher/48413 56.0 0.153 177.6 0.484 2.9 0.008 2.9 0.008 20.5 0Scurry/48415 102.8 0.280 435.9 1.187 7.3 0.020 7.1 0.019 55.3 0Shackelford/48417 11.8 0.032 50.7 0.138 0.8 0.002 0.8 0.002 5.9 0Shelby/48419 95.6 0.260 364.2 0.992 6.0 0.016 5.9 0.016 43.0 0Sherman/48421 7.3 0.020 29.2 0.079 0.5 0.001 0.5 0.001 3.3 0Smith/48423 1258.9 3.474 5165.4 14.253 86.0 0.237 84.1 0.232 590.6 Somervell/48425 2.9 0.008 11.9 0.032 0.2 0.001 0.2 0.001 1.4 0Starr/48427 149.9 0.408 472.9 1.288 7.8 0.021 7.6 0.021 53.7 0Stephens/48429 28.9 0.079 121.1 0.330 2.0 0.005 2.0 0.005 14.3 0Sterling/48431 50.8 0.138 216.3 0.589 3.6 0.010 3.5 0.010 25.8 0Stonewall/48433 5.0 0.014 21.8 0.059 0.4 0.001 0.4 0.001 2.5 0Sutton/48435 76.7 0.209 266.6 0.726 4.4 0.012 4.3 0.012 30.2 0Swisher/48437 Tarrant/48439 329.7 0.896 1110.4 3.017 18.3 0.050 17.9 0.049 125.5 0Taylor/48441 1.6 0.004 6.3 0.017 0.1 0.000 0.1 0.000 1.0 0Terrell/48443 127.9 0.348 504.3 1.373 8.4 0.023 8.2 0.022 58.1 0Terry/48445 30.6 0.083 133.3 0.363 2.2 0.006 2.2 0.006 15.4 0Throckmorton/48447 5.3 0.015 22.8 0.062 0.4 0.001 0.4 0.001 2.8 0Titus/48449 1.3 0.004 5.7 0.016 0.1 0.000 0.1 0.000 0.7 0Tom Green/48451 67.8 0.185 293.8 0.800 4.9 0.013 4.8 0.013 33.8 0Travis/48453 Trinity/48455 0.2 0.001 0.9 0.002 0.0 0.000 0.0 0.000 0.1 0Tyler/48457 305.2 0.831 1265.4 3.446 21.1 0.057 20.6 0.056 144.6 0Upshur/48459 241.1 0.665 1005.1 2.773 16.7 0.046 16.4 0.045 115.0 0Upton/48461 602.7 1.641 2465.6 6.715 41.0 0.112 40.1 0.109 287.4 0Uvalde/48463 Val Verde/48465 66.5 0.181 272.4 0.742 4.5 0.012 4.4 0.012 31.1 0
3

-16

Table 3-4a. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissi

Exploration Sources (Cont.) 

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Van Zandt/48467 3.8 0.010 16.7 0.045 0.3 0.001 0.3 0.001 1.9 0Victoria/48469 30.7 0.084 110.2 0.300 1.8 0.005 1.8 0.005 12.8 0Walker/48471 9.9 0.027 41.2 0.112 0.7 0.002 0.7 0.002 4.9 0Waller/48473 33.4 0.091 140.1 0.382 2.3 0.006 2.3 0.006 16.9 0Ward/48475 218.1 0.594 942.0 2.565 15.7 0.043 15.4 0.042 110.2 0Washington/48477 58.3 0.159 208.8 0.569 3.5 0.009 3.4 0.009 23.8 0Webb/48479 718.3 1.956 2738.4 7.458 45.4 0.124 44.4 0.121 311.5 0Wharton/48481 224.6 0.612 877.0 2.388 14.6 0.040 14.2 0.039 100.5 0Wheeler/48483 2246.7 6.118 9524.6 25.938 158.8 0.433 155.3 0.423 1090.4 2Wichita/48485 14.4 0.039 62.7 0.171 1.0 0.003 1.0 0.003 7.2 0Wilbarger/48487 39.5 0.107 171.9 0.468 2.9 0.008 2.8 0.008 19.7 0Willacy/48489 51.9 0.141 194.7 0.530 3.2 0.009 3.2 0.009 22.4 0Williamson/48491 Wilson/48493 7.4 0.020 32.1 0.088 0.5 0.001 0.5 0.001 3.7 0Winkler/48495 183.1 0.499 779.6 2.123 13.0 0.035 12.7 0.035 92.5 0Wise/48497 609.3 1.656 2407.0 6.541 40.0 0.109 39.1 0.106 278.7 0Wood/48499 8.7 0.024 37.6 0.102 0.6 0.002 0.6 0.002 4.4 0Yoakum/48501 116.2 0.316 497.5 1.355 8.3 0.023 8.1 0.022 59.9 0Young/48503 10.6 0.029 45.3 0.123 0.8 0.002 0.7 0.002 5.3 0Zapata/48505 1115.6 3.038 4175.0 11.370 69.2 0.188 67.7 0.184 474.5 Zavala/48507 44.4 0.121 193.4 0.527 3.2 0.009 3.2 0.009 22.3 0

Total 29,695 80.96 120,061 327.33 1,998 5.45 1,954 5.33 13,835 3

In order to reflect significant figures, estimates should be interpreted as follows: 0.0 = <0.1; 0.00 = <0.01; and 0.000 = <0.0
3

-17

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Anderson/48001 179.8 0.490 185.8 0.506 3.1 0.008 3.1 0.008 0.1 0Andrews/48003 562.0 1.531 623.2 1.697 9.4 0.026 9.4 0.026 0.3 0Angelina/48005 21.2 0.058 21.8 0.059 0.4 0.001 0.4 0.001 0.0 0Aransas/48007 94.2 0.257 96.9 0.264 1.6 0.004 1.6 0.004 0.0 0Archer/48009 8.9 0.024 11.2 0.031 0.1 0.000 0.1 0.000 0.0 0Armstrong/48011 Atascosa/48013 94.5 0.258 98.2 0.268 1.6 0.004 1.6 0.004 0.0 0Austin/48015 205.3 0.560 211.0 0.576 3.5 0.010 3.5 0.010 0.1 0Bailey/48017 Bandera/48019 0.0 0.000 0.0 0.000 Bastrop/48021 5.8 0.016 6.1 0.017 0.1 0.000 0.1 0.000 0.0 0Baylor/48023 0.1 0.000 0.3 0.001 0.0 0.000 0.0 0.000 0.0 0Bee/48025 616.1 1.678 632.1 1.721 10.5 0.029 10.5 0.029 0.3 0Bell/48027 Bexar/48029 0.1 0.000 0.3 0.001 0.0 0.000 0.0 0.000 0.0 0Blanco/48031 Borden/48033 42.5 0.116 52.3 0.142 0.7 0.002 0.7 0.002 0.0 0Bosque/48035 Bowie/48037 4.9 0.013 5.2 0.014 0.1 0.000 0.1 0.000 0.0 0Brazoria/48039 221.4 0.604 266.9 0.728 9.5 0.026 9.5 0.026 0.3 0Brazos/48041 184.8 0.503 193.3 0.526 3.1 0.009 3.1 0.009 0.1 0Brewster/48043 Briscoe/48045 Brooks/48047 1258.6 3.428 1291.9 3.518 21.4 0.058 21.4 0.058 0.6 0Brown/48049 24.9 0.068 25.7 0.070 0.4 0.001 0.4 0.001 0.0 0Burleson/48051 226.4 0.617 236.4 0.644 3.8 0.010 3.8 0.010 0.1 0Burnet/48053 Caldwell/48055 7.8 0.021 9.8 0.027 0.1 0.000 0.1 0.000 0.0 0Calhoun/48057 189.8 0.517 195.5 0.532 3.2 0.009 3.2 0.009 0.1 0Callahan/48059 15.8 0.043 16.6 0.045 0.3 0.001 0.3 0.001 0.0 0
3

-18

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Cameron/48061 3.0 0.008 3.0 0.008 0.1 0.000 0.1 0.000 0.0 0Camp/48063 14.2 0.039 15.0 0.041 0.2 0.001 0.2 0.001 0.0 0Carson/48065 312.1 0.850 320.3 0.872 5.3 0.014 5.3 0.014 0.1 0Cass/48067 56.2 0.153 58.2 0.158 1.0 0.003 1.0 0.003 0.0 0Castro/48069 Chambers/48071 101.5 0.277 122.7 0.335 4.3 0.012 4.3 0.012 0.1 0Cherokee/48073 229.4 0.625 235.6 0.642 3.9 0.011 3.9 0.011 0.1 0Childress/48075 0.0 0.000 0.1 0.000 0.0 0.000 0.0 0.000 0.0 0Clay/48077 13.7 0.037 15.5 0.042 0.2 0.001 0.2 0.001 0.0 0Cochran/48079 44.2 0.120 52.9 0.144 0.7 0.002 0.7 0.002 0.0 0Coke/48081 54.2 0.148 56.4 0.154 0.9 0.003 0.9 0.003 0.0 0Coleman/48083 30.6 0.083 31.9 0.087 0.5 0.001 0.5 0.001 0.0 0Collin/48085 Collingsworth/48087 20.9 0.057 21.4 0.058 0.4 0.001 0.4 0.001 0.0 0Colorado/48089 347.6 0.947 356.8 0.972 5.9 0.016 5.9 0.016 0.2 0Comal/48091 Comanche/48093 11.4 0.031 11.7 0.032 0.2 0.001 0.2 0.001 0.0 0Concho/48095 23.8 0.065 25.2 0.069 0.4 0.001 0.4 0.001 0.0 0Cooke/48097 21.5 0.059 25.2 0.069 0.4 0.001 0.4 0.001 0.0 0Coryell/48099 Cottle/48101 78.5 0.214 80.6 0.219 1.3 0.004 1.3 0.004 0.0 0Crane/48103 956.9 2.606 999.9 2.723 16.2 0.044 16.2 0.044 0.4 0Crockett/48105 1847.8 5.032 1901.4 5.178 31.5 0.086 31.5 0.086 0.9 0Crosby/48107 1.2 0.003 2.3 0.006 0.0 0.000 0.0 0.000 0.0 0Culberson/48109 24.7 0.067 25.6 0.070 0.4 0.001 0.4 0.001 0.0 0Dallam/48111 Dallas/48113 Dawson/48115 39.9 0.109 49.9 0.136 0.6 0.002 0.6 0.002 0.0 0Deaf Smith/48117 Delta/48119 
3

-19

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Denton/48121 1615.0 4.398 1616.7 4.403 38.7 0.105 38.7 0.105 1.1 0De Witt/48123 502.6 1.369 516.2 1.406 8.6 0.023 8.6 0.023 0.2 0Dickens/48125 2.9 0.008 6.0 0.016 0.0 0.000 0.0 0.000 0.0 0Dimmit/48127 59.0 0.161 62.4 0.170 1.0 0.003 1.0 0.003 0.0 0Donley/48129 0.3 0.001 0.3 0.001 0.0 0.000 0.0 0.000 0.0 0Duval/48131 1038.8 2.829 1066.7 2.905 17.7 0.048 17.7 0.048 0.5 0Eastland/48133 76.3 0.208 78.8 0.215 1.3 0.004 1.3 0.004 0.0 0Ector/48135 709.4 1.932 764.8 2.083 11.9 0.032 11.9 0.032 0.3 0Edwards/48137 287.1 0.782 294.0 0.801 4.9 0.013 4.9 0.013 0.1 0Ellis/48139 0.5 0.001 0.5 0.001 0.0 0.000 0.0 0.000 0.0 0El Paso/48141 Erath/48143 32.1 0.087 32.9 0.089 0.5 0.001 0.5 0.001 0.0 0Falls/48145 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0Fannin/48147 Fayette/48149 367.9 1.002 380.3 1.036 6.3 0.017 6.3 0.017 0.2 0Fisher/48151 12.8 0.035 14.2 0.039 0.2 0.001 0.2 0.001 0.0 0Floyd/48153 0.0 0.000 0.0 0.000 Foard/48155 14.4 0.039 14.9 0.041 0.2 0.001 0.2 0.001 0.0 0Fort Bend/48157 228.6 0.623 276.0 0.753 9.7 0.027 9.7 0.027 0.3 0Franklin/48159 53.9 0.147 56.1 0.153 0.9 0.002 0.9 0.002 0.0 0Freestone/48161 4309.4 11.736 4414.3 12.021 73.5 0.200 73.5 0.200 2.0 0Frio/48163 18.4 0.050 20.0 0.054 0.3 0.001 0.3 0.001 0.0 0Gaines/48165 544.1 1.482 614.9 1.675 9.0 0.025 9.0 0.025 0.2 0Galveston/48167 70.3 0.192 85.8 0.234 3.0 0.008 3.0 0.008 0.1 0Garza/48169 16.1 0.044 24.6 0.067 0.2 0.001 0.2 0.001 0.0 0Gillespie/48171 Glasscock/48173 212.6 0.579 225.0 0.613 3.6 0.010 3.6 0.010 0.1 0Goliad/48175 1203.0 3.276 1234.0 3.361 20.5 0.056 20.5 0.056 0.6 0Gonzales/48177 19.1 0.052 20.1 0.055 0.3 0.001 0.3 0.001 0.0 0Gray/48179 217.1 0.591 224.9 0.612 3.7 0.010 3.7 0.010 0.1 0
3

-20

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Grayson/48181 100.9 0.275 106.3 0.289 1.7 0.005 1.7 0.005 0.0 0Gregg/48183 1079.8 2.979 1111.8 3.068 18.4 0.051 18.4 0.051 0.5 0Grimes/48185 304.6 0.830 312.3 0.851 5.2 0.014 5.2 0.014 0.1 0Guadalupe/48187 1.5 0.004 4.6 0.012 0.0 0.000 0.0 0.000 0.0 0Hale/48189 19.7 0.054 25.8 0.070 0.3 0.001 0.3 0.001 0.0 0Hall/48191 Hamilton/48193 2.6 0.007 2.7 0.007 0.0 0.000 0.0 0.000 0.0 0Hansford/48195 403.1 1.098 413.2 1.125 6.9 0.019 6.9 0.019 0.2 0Hardeman/48197 10.7 0.029 14.6 0.040 0.2 0.000 0.2 0.000 0.0 0Hardin/48199 77.0 0.209 85.0 0.231 2.3 0.006 2.3 0.006 0.1 0Harris/48201 160.6 0.438 194.0 0.529 6.9 0.019 6.9 0.019 0.2 0Harrison/48203 1228.4 3.390 1260.2 3.477 20.9 0.058 20.9 0.058 0.6 0Hartley/48205 37.5 0.102 38.8 0.106 0.6 0.002 0.6 0.002 0.0 0Haskell/48207 0.9 0.002 1.6 0.004 0.0 0.000 0.0 0.000 0.0 0Hays/48209 Hemphill/48211 1720.9 4.686 1765.0 4.807 29.3 0.080 29.3 0.080 0.8 0Henderson/48213 636.9 1.734 653.5 1.780 10.9 0.030 10.9 0.030 0.3 0Hidalgo/48215 3336.6 9.086 3422.9 9.322 56.9 0.155 56.9 0.155 1.6 0Hill/48217 0.1 0.000 0.1 0.000 0.0 0.000 0.0 0.000 0.0 0Hockley/48219 164.9 0.449 208.7 0.568 2.6 0.007 2.6 0.007 0.1 0Hood/48221 86.6 0.236 88.8 0.242 1.5 0.004 1.5 0.004 0.0 0Hopkins/48223 20.4 0.056 21.7 0.059 0.3 0.001 0.3 0.001 0.0 0Houston/48225 182.4 0.497 188.3 0.513 3.1 0.008 3.1 0.008 0.1 0Howard/48227 104.0 0.283 118.5 0.323 1.7 0.005 1.7 0.005 0.0 0Hudspeth/48229 Hunt/48231 Hutchinson/48233 241.0 0.656 248.5 0.677 4.1 0.011 4.1 0.011 0.1 0Irion/48235 150.3 0.409 156.8 0.427 2.5 0.007 2.5 0.007 0.1 0Jack/48237 246.1 0.670 253.4 0.690 4.2 0.011 4.2 0.011 0.1 0Jackson/48239 460.1 1.253 473.3 1.289 7.8 0.021 7.8 0.021 0.2 0
3

-21

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Jasper/48241 137.8 0.375 142.0 0.387 2.3 0.006 2.3 0.006 0.1 0Jeff Davis/48243 Jefferson/48245 328.0 0.891 353.3 0.960 9.9 0.027 9.9 0.027 0.3 0Jim Hogg/48247 436.1 1.188 447.3 1.218 7.4 0.020 7.4 0.020 0.2 0Jim Wells/48249 149.7 0.408 153.7 0.419 2.5 0.007 2.5 0.007 0.1 0Johnson/48251 688.5 1.871 688.6 1.871 16.5 0.045 16.5 0.045 0.5 0Jones/48253 10.3 0.028 12.2 0.033 0.2 0.000 0.2 0.000 0.0 0Karnes/48255 145.4 0.396 149.6 0.407 2.5 0.007 2.5 0.007 0.1 0Kaufman/48257 0.1 0.000 0.2 0.001 0.0 0.000 0.0 0.000 0.0 0Kendall/48259 Kenedy/48261 778.5 2.120 797.9 2.173 13.3 0.036 13.3 0.036 0.4 0Kent/48263 136.5 0.372 149.7 0.408 2.3 0.006 2.3 0.006 0.1 0Kerr/48265 0.0 0.000 0.0 0.000 Kimble/48267 5.0 0.014 5.2 0.014 0.1 0.000 0.1 0.000 0.0 0King/48269 34.9 0.095 39.9 0.109 0.6 0.002 0.6 0.002 0.0 0Kinney/48271 Kleberg/48273 448.0 1.220 459.7 1.252 7.6 0.021 7.6 0.021 0.2 0Knox/48275 0.1 0.000 0.6 0.002 0.0 0.000 0.0 0.000 0.0 0Lamar/48277 Lamb/48279 3.6 0.010 5.3 0.015 0.1 0.000 0.1 0.000 0.0 0Lampasas/48281 La Salle/48283 225.2 0.613 231.2 0.630 3.8 0.010 3.8 0.010 0.1 0Lavaca/48285 1106.0 3.012 1133.9 3.088 18.9 0.051 18.9 0.051 0.5 0Lee/48287 216.3 0.589 224.9 0.612 3.7 0.010 3.7 0.010 0.1 0Leon/48289 672.5 1.831 690.8 1.881 11.5 0.031 11.5 0.031 0.3 0Liberty/48291 353.1 0.963 424.9 1.159 15.1 0.041 15.1 0.041 0.5 0Limestone/48293 1129.1 3.075 1156.7 3.150 19.2 0.052 19.2 0.052 0.5 0Lipscomb/48295 793.0 2.159 813.6 2.216 13.5 0.037 13.5 0.037 0.4 0Live Oak/48297 386.7 1.053 397.3 1.082 6.6 0.018 6.6 0.018 0.2 0Llano/48299 
3

-22

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Loving/48301 1045.8 2.848 1073.2 2.923 17.8 0.049 17.8 0.049 0.5 0Lubbock/48303 2.4 0.007 5.6 0.015 0.0 0.000 0.0 0.000 0.0 0Lynn/48305 0.9 0.002 1.3 0.003 0.0 0.000 0.0 0.000 0.0 0McCulloch/48307 0.5 0.001 0.7 0.002 0.0 0.000 0.0 0.000 0.0 0McLennan/48309 0.0 0.000 0.0 0.000 McMullen/48311 929.0 2.530 954.0 2.598 15.8 0.043 15.8 0.043 0.4 0Madison/48313 121.7 0.331 125.7 0.342 2.1 0.006 2.1 0.006 0.1 0Marion/48315 82.6 0.225 85.0 0.231 1.4 0.004 1.4 0.004 0.0 0Martin/48317 174.6 0.475 189.1 0.515 2.9 0.008 2.9 0.008 0.1 0Mason/48319 Matagorda/48321 471.7 1.285 485.5 1.322 8.0 0.022 8.0 0.022 0.2 0Maverick/48323 75.0 0.204 79.2 0.216 1.3 0.003 1.3 0.003 0.0 0Medina/48325 0.2 0.001 0.4 0.001 0.0 0.000 0.0 0.000 0.0 0Menard/48327 1.8 0.005 2.1 0.006 0.0 0.000 0.0 0.000 0.0 0Midland/48329 887.7 2.417 930.2 2.533 15.0 0.041 15.0 0.041 0.4 0Milam/48331 6.6 0.018 7.7 0.021 0.1 0.000 0.1 0.000 0.0 0Mills/48333 0.2 0.001 0.3 0.001 0.0 0.000 0.0 0.000 0.0 0Mitchell/48335 9.3 0.025 15.8 0.043 0.1 0.000 0.1 0.000 0.0 0Montague/48337 39.2 0.107 43.1 0.117 0.7 0.002 0.7 0.002 0.0 0Montgomery/48339 57.5 0.157 69.7 0.190 2.4 0.007 2.4 0.007 0.1 0Moore/48341 677.6 1.845 694.6 1.892 11.5 0.031 11.5 0.031 0.3 0Morris/48343 0.0 0.000 0.0 0.000 Motley/48345 0.0 0.000 0.1 0.000 0.0 0.000 0.0 0.000 0.0 0Nacogdoches/48347 1025.6 2.793 1051.0 2.862 17.5 0.048 17.5 0.048 0.5 0Navarro/48349 8.8 0.024 9.6 0.026 0.1 0.000 0.1 0.000 0.0 0Newton/48351 54.7 0.149 57.3 0.156 0.9 0.003 0.9 0.003 0.0 0Nolan/48353 32.5 0.089 35.9 0.098 0.5 0.001 0.5 0.001 0.0 0Nueces/48355 990.2 2.699 1016.9 2.772 16.9 0.046 16.9 0.046 0.5 0Ochiltree/48357 442.5 1.205 455.0 1.239 7.5 0.021 7.5 0.021 0.2 0Oldham/48359 3.5 0.010 3.7 0.010 0.1 0.000 0.1 0.000 0.0 0
3

-23

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Orange/48361 108.9 0.296 117.3 0.319 3.3 0.009 3.3 0.009 0.1 0Palo Pinto/48363 226.3 0.616 232.4 0.633 3.9 0.011 3.9 0.011 0.1 0Panola/48365 4282.2 11.662 4390.3 11.956 73.0 0.199 73.0 0.199 2.0 0Parker/48367 231.3 0.629 231.5 0.629 5.5 0.015 5.5 0.015 0.2 0Parmer/48369 Pecos/48371 2951.9 8.039 3045.7 8.294 50.2 0.137 50.2 0.137 1.4 0Polk/48373 348.1 0.948 358.7 0.977 5.9 0.016 5.9 0.016 0.2 0Potter/48375 257.8 0.702 264.3 0.720 4.4 0.012 4.4 0.012 0.1 0Presidio/48377 Rains/48379 90.5 0.246 92.7 0.252 1.5 0.004 1.5 0.004 0.0 0Randall/48381 Reagan/48383 445.4 1.213 466.4 1.270 7.5 0.021 7.5 0.021 0.2 0Real/48385 7.7 0.021 7.9 0.021 0.1 0.000 0.1 0.000 0.0 0Red River/48387 0.1 0.000 0.4 0.001 0.0 0.000 0.0 0.000 0.0 0Reeves/48389 425.5 1.159 437.4 1.191 7.2 0.020 7.2 0.020 0.2 0Refugio/48391 768.9 2.094 797.4 2.171 13.1 0.036 13.1 0.036 0.4 0Roberts/48393 565.1 1.539 580.5 1.581 9.6 0.026 9.6 0.026 0.3 0Robertson/48395 1831.9 4.989 1878.5 5.116 31.2 0.085 31.2 0.085 0.9 0Rockwall/48397 Runnels/48399 25.3 0.069 26.9 0.073 0.4 0.001 0.4 0.001 0.0 0Rusk/48401 1465.6 4.044 1506.5 4.157 25.0 0.069 25.0 0.069 0.7 0Sabine/48403 0.6 0.002 0.6 0.002 0.0 0.000 0.0 0.000 0.0 0San Augustine/48405 0.5 0.001 0.5 0.001 0.0 0.000 0.0 0.000 0.0 0San Jacinto/48407 93.2 0.254 95.9 0.262 1.6 0.004 1.6 0.004 0.0 0San Patricio/48409 497.1 1.355 512.0 1.396 8.5 0.023 8.5 0.023 0.2 0San Saba/48411 Schleicher/48413 199.1 0.542 204.8 0.558 3.4 0.009 3.4 0.009 0.1 0Scurry/48415 421.1 1.147 463.7 1.263 7.0 0.019 7.0 0.019 0.2 0Shackelford/48417 52.5 0.143 55.2 0.150 0.9 0.002 0.9 0.002 0.0 0Shelby/48419 617.1 1.681 632.6 1.723 10.5 0.029 10.5 0.029 0.3 0
3

-24

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Sherman/48421 350.1 0.953 358.8 0.977 6.0 0.016 6.0 0.016 0.2 0Smith/48423 824.0 2.274 847.2 2.338 14.0 0.039 14.0 0.039 0.4 0Somervell/48425 1.9 0.005 2.0 0.005 0.0 0.000 0.0 0.000 0.0 0Starr/48427 2053.2 5.591 2107.6 5.740 35.0 0.095 35.0 0.095 1.0 0Stephens/48429 200.7 0.546 210.1 0.572 3.4 0.009 3.4 0.009 0.1 0Sterling/48431 264.9 0.721 273.8 0.746 4.5 0.012 4.5 0.012 0.1 0Stonewall/48433 8.3 0.023 10.6 0.029 0.1 0.000 0.1 0.000 0.0 0Sutton/48435 1320.9 3.597 1353.1 3.685 22.5 0.061 22.5 0.061 0.6 0Swisher/48437 Tarrant/48439 1283.6 3.488 1283.8 3.489 30.7 0.084 30.7 0.084 0.9 0Taylor/48441 3.9 0.011 5.1 0.014 0.1 0.000 0.1 0.000 0.0 0Terrell/48443 1060.9 2.889 1087.2 2.961 18.1 0.049 18.1 0.049 0.5 0Terry/48445 24.0 0.065 32.9 0.090 0.4 0.001 0.4 0.001 0.0 0Throckmorton/48447 25.7 0.070 28.0 0.076 0.4 0.001 0.4 0.001 0.0 0Titus/48449 0.3 0.001 1.3 0.004 0.0 0.000 0.0 0.000 0.0 0Tom Green/48451 41.9 0.114 43.9 0.120 0.7 0.002 0.7 0.002 0.0 0Travis/48453 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0Trinity/48455 3.4 0.009 3.7 0.010 0.1 0.000 0.1 0.000 0.0 0Tyler/48457 298.8 0.814 311.0 0.847 5.1 0.014 5.1 0.014 0.1 0Upshur/48459 834.2 2.302 855.7 2.361 14.2 0.039 14.2 0.039 0.4 0Upton/48461 1232.3 3.356 1284.3 3.498 20.9 0.057 20.9 0.057 0.6 0Uvalde/48463 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0Val Verde/48465 291.7 0.794 298.8 0.814 5.0 0.014 5.0 0.014 0.1 0Van Zandt/48467 117.5 0.320 122.2 0.333 2.0 0.005 2.0 0.005 0.1 0Victoria/48469 345.0 0.939 355.0 0.967 5.9 0.016 5.9 0.016 0.2 0Walker/48471 17.8 0.049 18.3 0.050 0.3 0.001 0.3 0.001 0.0 0Waller/48473 27.1 0.074 34.4 0.094 1.1 0.003 1.1 0.003 0.0 0Ward/48475 787.0 2.143 815.6 2.221 13.4 0.036 13.4 0.036 0.4 0Washington/48477 418.5 1.140 429.9 1.171 7.1 0.019 7.1 0.019 0.2 0Webb/48479 3826.4 10.420 3921.9 10.681 65.2 0.178 65.2 0.178 1.8 0
3

-25

Table 3-4b. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Produ

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr to

Wharton/48481 903.9 2.462 929.8 2.532 15.4 0.042 15.4 0.042 0.4 0Wheeler/48483 1016.8 2.769 1044.3 2.844 17.3 0.047 17.3 0.047 0.5 0Wichita/48485 5.0 0.014 9.4 0.026 0.1 0.000 0.1 0.000 0.0 0Wilbarger/48487 0.7 0.002 2.2 0.006 0.0 0.000 0.0 0.000 0.0 0Willacy/48489 453.2 1.234 466.5 1.271 7.7 0.021 7.7 0.021 0.2 0Williamson/48491 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0Wilson/48493 0.6 0.002 1.2 0.003 0.0 0.000 0.0 0.000 0.0 0Winkler/48495 627.9 1.710 650.4 1.771 10.7 0.029 10.7 0.029 0.3 0Wise/48497 2774.8 7.540 2844.0 7.728 47.3 0.129 47.3 0.129 1.3 0Wood/48499 216.8 0.590 230.7 0.628 3.7 0.010 3.7 0.010 0.1 0Yoakum/48501 442.0 1.204 503.4 1.371 7.3 0.020 7.3 0.020 0.2 0Young/48503 55.2 0.150 59.1 0.161 0.9 0.003 0.9 0.003 0.0 0Zapata/48505 4938.6 13.449 5058.8 13.777 84.2 0.229 84.2 0.229 2.3 0Zavala/48507 22.2 0.061 24.5 0.067 0.4 0.001 0.4 0.001 0.0 0

Total 88,949 242.41 91,998 250.72 1,578 4.30 1,578 4.30 44 

In order to reflect significant figures, estimates should be interpreted as follows: 0.0 = <0.1; 0.00 = <0.01; and 0.000 = <0.0
3

-26

Table 3-4c. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Of

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr 

Aransas/48007 70.1 0.191 195.3 0.532 3.5 0.010 3.5 0.009 13.1 Brazoria/48039 239.0 0.652 495.8 1.352 9.5 0.026 9.5 0.026 10.8 Calhoun/48057 456.8 1.244 947.7 2.581 18.1 0.049 18.1 0.049 20.7 Cameron/48061 Chambers/48071 54.4 0.148 112.8 0.308 2.2 0.006 2.2 0.006 2.5 Galveston/48167 223.2 0.609 531.1 1.448 9.8 0.027 9.8 0.027 23.6 Jefferson/48245 750.0 2.038 1646.6 4.474 31.1 0.084 31.0 0.084 52.0 Kenedy/48261 231.9 0.631 481.1 1.310 9.2 0.025 9.2 0.025 10.5 Kleberg/48273 131.3 0.358 272.4 0.742 5.2 0.014 5.2 0.014 5.9 Matagorda/48321 385.3 1.049 802.2 2.185 15.3 0.042 15.3 0.042 18.0 Nueces/48355 137.7 0.375 355.8 0.970 6.5 0.018 6.4 0.018 20.2 San Patricio/48409 Willacy/48489 Brazos, Block 376 13.3 0.036 8.8 0.024 0.1 0.000 0.1 0.000 0.0 Brazos, Block 397 127.1 0.346 82.2 0.224 0.3 0.001 0.3 0.001 0.0 Brazos, Block 415 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Brazos, Block 451 245.2 0.668 158.9 0.433 0.7 0.002 0.7 0.002 0.0 Brazos, Block 453 139.6 0.380 91.6 0.249 0.4 0.001 0.4 0.001 2.0 Brazos, Block 491 21.9 0.060 14.2 0.039 0.1 0.000 0.1 0.000 0.0 Brazos, Block 542 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Galveston, Block 190 17.6 0.048 16.6 0.045 0.4 0.001 0.4 0.001 0.0 Galveston, Block 209 116.3 0.317 271.8 0.740 4.7 0.013 4.7 0.013 0.1 Galveston, Block 223 10.3 0.028 15.6 0.043 0.0 0.000 0.0 0.000 0.0 Galveston, Block 225 Galveston, Block 239 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Galveston, Block 255 29.1 0.079 19.3 0.053 0.1 0.000 0.1 0.000 0.0 Galveston, Block 273 95.0 0.259 68.6 0.187 0.8 0.002 0.8 0.002 0.0 Galveston, Block 301 10.0 0.027 7.3 0.020 0.0 0.000 0.0 0.000 0.0 Galveston, Block 303 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Galveston, Block 333 2.5 0.007 10.7 0.029 0.7 0.002 0.7 0.002 0.0 
3

-27

Table 3-4c. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Offsho

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr 

Galveston, Block 343 84.6 0.231 56.9 0.155 0.0 0.000 0.0 0.000 0.1 Galveston, Block 395 10.3 0.028 6.9 0.019 0.0 0.000 0.0 0.000 0.0 High Island, Block 021 High Island, Block 022 36.5 0.099 23.6 0.064 0.1 0.000 0.1 0.000 0.0 High Island, Block 034 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 High Island, Block 037 0.2 0.001 0.3 0.001 0.0 0.000 0.0 0.000 0.0 High Island, Block 039 59.4 0.162 38.4 0.105 0.2 0.000 0.2 0.000 0.0 High Island, Block 045 122.9 0.335 79.5 0.217 0.3 0.001 0.3 0.001 0.0 High Island, Block 046 3.2 0.009 2.2 0.006 0.0 0.000 0.0 0.000 0.0 High Island, Block 052 15.3 0.042 9.9 0.027 0.0 0.000 0.0 0.000 0.0 High Island, Block 072 High Island, Block 084 7.8 0.021 11.9 0.032 0.0 0.000 0.0 0.000 0.0 High Island, Block 085 148.8 0.405 96.3 0.262 0.4 0.001 0.4 0.001 0.0 High Island, Block 110 56.6 0.154 37.7 0.103 0.2 0.001 0.2 0.001 0.0 High Island, Block 116 67.5 0.184 44.0 0.120 0.2 0.001 0.2 0.001 0.0 High Island, Block 136 123.2 0.335 82.0 0.223 0.5 0.001 0.5 0.001 0.0 High Island, Block 140 39.9 0.109 26.2 0.071 0.1 0.000 0.1 0.000 0.0 High Island, Block 154 12.4 0.034 13.6 0.037 0.2 0.001 0.2 0.001 0.0 High Island, Block 176 274.5 0.748 179.0 0.487 0.9 0.002 0.9 0.002 0.0 High Island, Block 177 96.2 0.262 79.3 0.216 0.9 0.002 0.9 0.002 0.0 High Island, Block 179 172.3 0.469 115.8 0.315 0.5 0.001 0.5 0.001 0.0 High Island, Block 194 Matagorda Island, Block 487 65.0 0.177 42.1 0.115 0.2 0.000 0.2 0.000 0.0 Matagorda Island, Block 555 112.6 0.307 75.0 0.204 0.5 0.001 0.5 0.001 0.0 Matagorda Island, Block 566 2.8 0.008 4.3 0.012 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 587 153.6 0.418 99.5 0.271 0.4 0.001 0.4 0.001 0.0 
3

-28

Table 3-4c. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Offsho

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr 

Matagorda Island, Block 588 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 603 0.6 0.002 0.4 0.001 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 604 219.7 0.598 144.6 0.394 0.8 0.002 0.8 0.002 0.0 Matagorda Island, Block 605 69.0 0.188 44.7 0.122 0.2 0.001 0.2 0.001 0.0 Matagorda Island, Block 618 31.1 0.085 29.4 0.080 0.1 0.000 0.1 0.000 0.0 Matagorda Island, Block 622 173.7 0.473 192.0 0.523 1.3 0.004 1.3 0.004 4.4 Matagorda Island, Block 623 187.7 0.511 127.0 0.346 1.0 0.003 1.0 0.003 0.0 Matagorda Island, Block 631 145.3 0.396 94.1 0.256 0.4 0.001 0.4 0.001 0.0 Matagorda Island, Block 632 180.7 0.492 117.6 0.320 0.5 0.001 0.5 0.001 0.1 Matagorda Island, Block 633 32.4 0.088 39.9 0.109 0.1 0.000 0.1 0.000 0.0 Matagorda Island, Block 635 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 638 74.8 0.204 48.4 0.132 0.2 0.001 0.2 0.001 0.0 Matagorda Island, Block 657 1.4 0.004 6.4 0.017 0.5 0.001 0.5 0.001 0.0 Matagorda Island, Block 685 1.2 0.003 1.9 0.005 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 686 150.9 0.411 98.9 0.269 0.5 0.001 0.5 0.001 0.0 Matagorda Island, Block 696 63.7 0.174 41.3 0.112 0.2 0.000 0.2 0.000 0.0 Matagorda Island, Block 699 72.7 0.198 47.2 0.129 0.2 0.001 0.2 0.001 0.0 
3

-29

Table 3-4c. County-Level Annual and Ozone Season Daily (OSD) Criteria Pollutant Emissions for Offsho

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr 

Mustang Island, Block 726 0.4 0.001 0.7 0.002 0.0 0.000 0.0 0.000 0.0 Mustang Island, Block 754 3.2 0.009 4.9 0.013 0.0 0.000 0.0 0.000 0.0 Mustang Island, Block 858 1.9 0.005 2.9 0.008 0.0 0.000 0.0 0.000 0.0 Sabine Pass-Louisiana, Block 006 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Sabine Pass-Louisiana, Block 010 162.3 0.442 105.3 0.287 0.5 0.001 0.5 0.001 0.0 Sabine Pass-Louisiana, Block 012 0.4 0.001 0.5 0.001 0.0 0.000 0.0 0.000 0.0 Sabine Pass-Louisiana, Block 013 272.9 0.743 185.3 0.505 1.5 0.004 1.5 0.004 0.0 Sabine Pass-Texas, Block 018 69.0 0.188 44.7 0.122 0.2 0.001 0.2 0.001 0.0 West Cameron, Block 021 0.0 0.000 0.1 0.000 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 022 0.6 0.002 0.8 0.002 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 043 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 044 49.3 0.134 57.0 0.155 2.2 0.006 2.2 0.006 0.0 West Cameron, Block 045 5.0 0.014 3.3 0.009 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 048 151.6 0.413 99.5 0.271 0.4 0.001 0.4 0.001 0.0 West Cameron, Block 053 20.3 0.055 19.1 0.052 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 116 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 130 7.8 0.021 8.8 0.024 0.3 0.001 0.3 0.001 0.0 West Cameron, Block 153 

Total 7,323 19.94 9,298 25.32 135 0.37 135 0.37 185 

In order to reflect significant figures, estimates should be interpreted as follows: 0.0 = <0.1; 0.00 = <0.01; and 0.000 = <0.0
3-30 

Mud Degasssing: similar to drilling rig engines, it would be preferred to obtain the actual 

number of drilling days. Another piece of information that could help produce more 

accurate estimates would be the mud types used at all sites. The inventory was

constructed assuming water-based muds, but some operators may use synthetic or oilbased muds. As indicated in the literature (MMS, 2007), the emission factors for 

synthetic – or oil-based muds are different. 

Well completions: More site-specific information on actual or typical number of venting 

and flaring days during well completions is needed. Based on the requirements in the

applicable TRC regulations, the inventory was developed assuming a conservative value 

of 10 days of venting. 

Offshore-state waters: Obtaining better information on the actual number of platforms in 

state waters would improve this part of the inventory. Platform activity by area-block 

information was available, but the inventory had to be developed using an assumption for 

number of platforms per lease. As per a TCEQ Houston-Galveston area inventory, it was 

assumed that for oil, one oil platform per oil lease was used and for gas, one gas platform 

per six gas leases was used (TCEQ, 2000). 

Dehydrators and Condensate Storage: The emission factors used for these categories 

came from the WRAP oil and gas study, and reflect factors developed in a different state. 

While the factors appear to be totally valid and acceptable, the inventory could be 

improved if emissions and controls information for these sources in Texas could be 

developed to better validate the factors used. 

3.2 Source Category Contributions by Pollutant 

3.2.1 Carbon Monoxide Emissions

Total statewide emissions of CO for onshore exploration and production and offshore 

production sources are estimated to be 125,968 tons per year. The top contributor to this amount 

is natural gas compressor engines used for onshore production (88,754 tons). Compressor 

engines were responsible then for 70.5% of total CO emissions in the oil and gas area source 

inventory. The next largest source after compressors was drilling rig engines used in 

exploration, constituting 21.8% of the CO emissions. The next four largest CO contributors are 

offshore platforms-federal waters compressor engines (3.6%), gas well completions (1.7%), 

offshore platforms-state waters compressor engines (0.68%), and offshore platforms-state waters 

natural gas turbines (0.68%). These six categories generate nearly 99% of the CO statewide 

estimate from oil and gas area sources. 

3.2.2 Nitrogen Oxide Emissions

Similar to CO emissions, oil and gas area source NOx emissions are also dominated by 

onshore exploration drilling rig engines and onshore production compressor engines. Total 

estimated NOx emissions for all oil and gas area sources included in this inventory are 221,357 

tons per year. Onshore exploration drilling rig engines make up 54.1% of this amount, while 
3-31 

onshore production compressor engines are responsible for 41.1%. The two categories combined 

generate over 95% of all estimated NOx emissions. The most significant of the remaining 

sources include offshore platforms-state waters natural gas turbines (1.5%), offshore platformsfederal waters compressor engines (1.5%), offshore platforms-state waters diesel engines 

(0.45%), onshore production heater treaters (0.44%), and offshore platforms-state waters 

compressor engines (0.38%). These seven categories constitute 99.4% of the NOx emissions 

estimated for oil and gas area sources statewide (including offshore sources). 

3.2.3 Volatile Organic Compound Emissions

Practically every source in the inventory emits VOC, some less than 1 ton a year, while 

others are estimated to release several hundred thousand tons per year. Total statewide VOC 

from the sources included in the inventory have been estimated at 841,295 tons per year. Five 

categories dominate this emissions total (80.2% of all VOC) – onshore production glycol

dehydrators (26.9%), onshore production condensate storage tanks (22.9%), onshore production 

gas wellheads (12.6%), onshore production crude oil storage tanks (9.1%), and pneumatic 

devices associated with onshore production gas and oil wells (8.7%). Of the remaining VOC 

emissions sources, six are responsible for 17.5% of VOC emissions, making these 11 categories 

the source of nearly 98% of all oil and gas area sources VOC emissions. The six categories 

comprising the 17.5% of emissions consists of onshore production pump and piping fugitives 

(5.1%), onshore production oil wellheads (4.1%), onshore production oil loading (3.2%), 

onshore exploration gas well completions (2.4%), exploration oil well completions (1.6%), and 

onshore exploration mud degassing (1.3%). 

3.2.4 Sulfur Dioxide Emissions

Estimated emissions of SO2 are clearly dominated by one source category – onshore 

exploration drilling rig engines. This category is estimated to release 97.4% of the total SO2 

emissions from oil and gas area sources. The next largest source of SO2 is onshore exploration 

oil well completions at 138 tons per year or 0.98% of total emissions. Diesel engines and 

drilling rig engines on offshore platforms-state waters are responsible for 0.56% and 0.44%, 

respectively, of total SO2 emissions. The remaining categories are estimated to be very minor 

SO2 emitters. 

3.2.5 Particulate Matter Emissions 

Contributions to PM10 and PM2.5 emissions track very consistently. Two categories 

dominate (over 96% of emissions) both PM10 and PM2.5 emissions – onshore exploration drilling 

rig engines and onshore production natural gas compressor engines. The contributions to 

emissions are summarized as follows. 

 PM10

 Drilling Rig Engines – 53.8% of emissions 

 Compressor Engines – 42.5% of emissions 
3-32 

 PM2.5

 Drilling Rig Engines – 53.3% of emissions 

 Compressor Engines – 43.0% of emissions 

The only other PM emissions category that is estimated to contribute at least 1% to total PM10 or 

PM2.5 emissions is diesel engines at offshore state waters platforms. This source category is 

responsible for approximately 1.9% of PM10 and PM2.5 emissions. All remaining PM10 and PM2.5 

categories are less than 1% contributors. 

3.3 Comparison of Emissions by County 

Table 3-5 contains a listing of pollutant emissions by county for all sources included in 

this inventory, i.e., the values represent the sum of all onshore exploration, onshore production, 

and offshore production platform emissions for each county. Both annual and OSD emission 

estimates are provided. For the offshore federal waters data, emissions are listed by lease block 

since these are not assigned to counties. Discussions regarding the contribution of emissions by 

county for each source grouping are provided below. 

3.3.1 Onshore Exploration 

Annual and OSD emissions for all pollutants are presented at the county level for onshore 

exploration sources collectively in Table 3-4a. For counties emitting all pollutants (i.e., have 

both combustion sources and evaporative sources), a total of 14 counties make up roughly 50% 

of all emissions. These counties (in approximate descending order) are: 

 Hemphill, 

 Wheeler, 

 Smith, 

 Zapata, 

 Crockett, 

 Denton, 

 Webb, 

 Panola, 

 Harrison, 

 Freestone, 

 Upton, 

 Wise, 

 LaSalle, and 

 Robertson. 

The lowest level of these counties represents about 2.0% of the emissions of any given pollutant 

such as CO, NOx, PM10, PM2.5 or SO2. The majority of the remaining Texas counties contribute 

less than 1% to total onshore exploration emissions, and many have emissions constituting less 

than 0.1% of the statewide total. 
3

-33

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Inv

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Anderson/48001 225.2 0.613 382.4 1.041 6.3 0.017 6.3 0.017 22.6 Andrews/48003 634.2 1.727 930.5 2.534 14.5 0.039 14.4 0.039 38.8 Angelina/48005 45.2 0.123 118.8 0.324 2.0 0.005 1.9 0.005 11.1 Aransas/48007 169.4 0.462 312.0 0.850 5.4 0.015 5.4 0.015 15.9 Archer/48009 44.7 0.122 167.2 0.455 2.7 0.007 2.7 0.007 17.9 Armstrong/48011 Atascosa/48013 118.1 0.322 200.5 0.547 3.3 0.009 3.3 0.009 11.7 Austin/48015 229.6 0.626 304.8 0.831 5.1 0.014 5.0 0.014 11.3 Bailey/48017 Bandera/48019 0.0 0.000 0.0 0.000 Bastrop/48021 5.8 0.016 6.1 0.017 0.1 0.000 0.1 0.000 0.0 Baylor/48023 3.7 0.010 16.3 0.044 0.3 0.001 0.3 0.001 1.8 Bee/48025 812.7 2.213 1446.5 3.939 24.1 0.066 23.8 0.065 93.3 Bell/48027 Bexar/48029 0.1 0.000 0.3 0.001 0.0 0.000 0.0 0.000 0.0 Blanco/48031 Borden/48033 77.5 0.211 204.2 0.556 3.2 0.009 3.2 0.009 17.8 Bosque/48035 3.2 0.009 13.9 0.038 0.2 0.001 0.2 0.001 1.6 Bowie/48037 7.2 0.020 15.2 0.042 0.2 0.001 0.2 0.001 1.2 Brazoria/48039 621.6 1.695 1429.0 3.897 30.0 0.082 29.8 0.081 87.7 Brazos/48041 226.7 0.617 363.5 0.990 6.0 0.016 5.9 0.016 21.8 Brewster/48043 Briscoe/48045 Brooks/48047 1447.3 3.941 2019.3 5.499 33.5 0.091 33.3 0.091 84.2 Brown/48049 29.5 0.080 45.5 0.124 0.8 0.002 0.7 0.002 2.3 Burleson/48051 256.1 0.697 358.2 0.975 5.9 0.016 5.8 0.016 17.4 Burnet/48053 Caldwell/48055 35.0 0.095 128.6 0.350 2.1 0.006 2.1 0.006 13.6 Calhoun/48057 706.5 1.924 1387.2 3.778 25.4 0.069 25.3 0.069 48.6 Callahan/48059 18.3 0.050 27.2 0.074 0.4 0.001 0.4 0.001 1.3 
3

-34

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Cameron/48061 3.0 0.008 3.0 0.008 0.1 0.000 0.1 0.000 0.0 Camp/48063 14.2 0.039 15.0 0.041 0.2 0.001 0.2 0.001 0.0 Carson/48065 313.1 0.853 324.2 0.883 5.4 0.015 5.4 0.015 0.7 Cass/48067 61.7 0.168 79.7 0.217 1.3 0.004 1.3 0.004 2.5 Castro/48069 Chambers/48071 201.1 0.548 396.9 1.083 9.2 0.025 9.1 0.025 23.2 Cherokee/48073 318.3 0.867 591.9 1.612 9.8 0.027 9.7 0.026 40.8 Childress/48075 0.0 0.000 0.1 0.000 0.0 0.000 0.0 0.000 0.0 Clay/48077 25.5 0.070 66.8 0.182 1.1 0.003 1.1 0.003 6.0 Cochran/48079 56.8 0.155 107.3 0.292 1.6 0.004 1.6 0.004 6.4 Coke/48081 67.0 0.182 111.4 0.303 1.8 0.005 1.8 0.005 6.7 Coleman/48083 31.9 0.087 36.9 0.100 0.6 0.002 0.6 0.002 0.6 Collin/48085 Collingsworth/48087 20.9 0.057 21.4 0.058 0.4 0.001 0.4 0.001 0.0 Colorado/48089 510.8 1.391 1031.4 2.809 17.2 0.047 16.9 0.046 77.2 Comal/48091 Comanche/48093 11.9 0.033 14.0 0.038 0.2 0.001 0.2 0.001 0.3 Concho/48095 53.0 0.144 143.9 0.392 2.4 0.006 2.3 0.006 13.7 Cooke/48097 196.6 0.535 785.2 2.138 13.0 0.036 12.8 0.035 87.4 Coryell/48099 Cottle/48101 115.4 0.314 234.9 0.640 3.9 0.011 3.9 0.010 17.7 Crane/48103 1008.1 2.745 1204.3 3.280 19.6 0.053 19.6 0.053 25.4 Crockett/48105 2593.0 7.061 4888.4 13.313 81.1 0.221 80.1 0.218 344.7 Crosby/48107 1.2 0.003 2.3 0.006 0.0 0.000 0.0 0.000 0.0 Culberson/48109 29.4 0.080 45.9 0.125 0.8 0.002 0.8 0.002 2.3 Dallam/48111 Dallas/48113 Dawson/48115 58.8 0.160 131.6 0.358 2.0 0.005 2.0 0.005 9.7 Deaf Smith/48117 Delta/48119 
3

-35

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Denton/48121 2346.5 6.390 4446.7 12.110 85.7 0.233 84.6 0.230 323.6 De Witt/48123 701.7 1.911 1307.7 3.561 21.7 0.059 21.4 0.058 90.5 Dickens/48125 14.9 0.041 57.8 0.157 0.9 0.002 0.9 0.002 6.1 Dimmit/48127 112.1 0.305 275.5 0.750 4.5 0.012 4.5 0.012 25.3 Donley/48129 0.3 0.001 0.3 0.001 0.0 0.000 0.0 0.000 0.0 Duval/48131 1212.5 3.302 1725.6 4.699 28.6 0.078 28.4 0.077 75.9 Eastland/48133 113.4 0.309 239.3 0.652 4.0 0.011 3.9 0.011 18.6 Ector/48135 911.7 2.483 1642.4 4.473 26.6 0.072 26.3 0.072 102.7 Edwards/48137 317.6 0.865 418.6 1.140 7.0 0.019 6.9 0.019 14.4 Ellis/48139 3.0 0.008 10.1 0.027 0.2 0.000 0.2 0.000 1.1 El Paso/48141 Erath/48143 40.5 0.110 65.3 0.178 1.1 0.003 1.1 0.003 3.8 Falls/48145 2.7 0.007 11.7 0.032 0.2 0.001 0.2 0.001 1.3 Fannin/48147 Fayette/48149 409.5 1.115 557.8 1.519 9.2 0.025 9.2 0.025 21.9 Fisher/48151 16.3 0.044 29.1 0.079 0.5 0.001 0.5 0.001 2.0 Floyd/48153 3.2 0.009 13.7 0.037 0.2 0.001 0.2 0.001 1.6 Foard/48155 17.9 0.049 29.4 0.080 0.5 0.001 0.5 0.001 1.7 Fort Bend/48157 336.0 0.916 693.7 1.892 16.7 0.046 16.5 0.045 48.3 Franklin/48159 81.8 0.223 174.8 0.476 2.9 0.008 2.9 0.008 14.3 Freestone/48161 4925.4 13.413 6878.8 18.733 114.5 0.312 113.6 0.309 283.0 Frio/48163 24.7 0.067 47.2 0.129 0.8 0.002 0.8 0.002 3.1 Gaines/48165 950.0 2.587 2367.0 6.446 38.3 0.104 37.6 0.102 202.7 Galveston/48167 313.0 0.854 695.6 1.897 14.1 0.039 14.1 0.038 33.3 Garza/48169 56.8 0.155 202.0 0.550 3.2 0.009 3.1 0.009 20.3 Gillespie/48171 Glasscock/48173 238.6 0.650 334.3 0.910 5.4 0.015 5.4 0.015 14.1 Goliad/48175 1647.1 4.485 2901.9 7.903 48.2 0.131 47.5 0.129 190.5 Gonzales/48177 25.6 0.070 48.2 0.131 0.8 0.002 0.8 0.002 3.2 Gray/48179 225.6 0.614 257.0 0.700 4.2 0.012 4.2 0.011 3.8 
3

-36

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Grayson/48181 189.7 0.517 488.9 1.331 8.1 0.022 8.0 0.022 45.8 Gregg/48183 1206.5 3.329 1558.5 4.300 25.8 0.071 25.6 0.071 51.2 Grimes/48185 391.5 1.066 583.2 1.588 9.6 0.026 9.5 0.026 30.6 Guadalupe/48187 13.3 0.036 56.1 0.153 0.9 0.002 0.9 0.002 5.9 Hale/48189 27.4 0.075 58.6 0.159 0.9 0.002 0.8 0.002 4.1 Hall/48191 Hamilton/48193 3.3 0.009 5.7 0.016 0.1 0.000 0.1 0.000 0.3 Hansford/48195 445.0 1.212 583.6 1.589 9.7 0.026 9.6 0.026 19.6 Hardeman/48197 70.3 0.191 274.0 0.746 4.5 0.012 4.4 0.012 29.9 Hardin/48199 136.7 0.372 323.3 0.879 6.3 0.017 6.2 0.017 28.6 Harris/48201 222.5 0.607 455.7 1.243 11.2 0.031 11.1 0.030 30.2 Harrison/48203 1854.8 5.118 3798.3 10.481 63.2 0.174 62.2 0.172 294.2 Hartley/48205 47.6 0.130 80.8 0.220 1.3 0.004 1.3 0.004 4.8 Haskell/48207 1.6 0.004 4.6 0.012 0.1 0.000 0.1 0.000 0.3 Hays/48209 Hemphill/48211 5254.9 14.311 16924.1 46.090 282.3 0.769 276.7 0.754 1739.8 Henderson/48213 667.5 1.818 769.1 2.094 12.8 0.035 12.7 0.035 13.5 Hidalgo/48215 3747.6 10.206 4954.2 13.492 82.2 0.224 81.7 0.222 175.6 Hill/48217 67.8 0.185 293.4 0.799 4.9 0.013 4.8 0.013 33.6 Hockley/48219 251.4 0.685 579.9 1.579 8.8 0.024 8.7 0.024 45.3 Hood/48221 134.6 0.367 260.7 0.710 4.3 0.012 4.3 0.012 19.5 Hopkins/48223 22.2 0.060 29.4 0.080 0.5 0.001 0.5 0.001 0.9 Houston/48225 251.2 0.684 443.3 1.207 7.3 0.020 7.2 0.020 29.1 Howard/48227 125.9 0.343 211.3 0.575 3.3 0.009 3.2 0.009 11.9 Hudspeth/48229 Hunt/48231 Hutchinson/48233 265.1 0.722 347.9 0.947 5.8 0.016 5.7 0.016 11.5 Irion/48235 369.2 1.005 1095.9 2.985 18.2 0.050 17.9 0.049 108.6 Jack/48237 348.5 0.949 678.3 1.847 11.3 0.031 11.1 0.030 49.4 Jackson/48239 523.1 1.425 690.2 1.880 11.4 0.031 11.3 0.031 25.5 
3

-37

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Jasper/48241 143.0 0.390 158.0 0.430 2.6 0.007 2.6 0.007 3.4 Jeff Davis/48243 Jefferson/48245 1168.1 3.174 2333.1 6.340 46.4 0.126 46.2 0.126 91.1 Jim Hogg/48247 647.9 1.765 1321.9 3.600 22.0 0.060 21.7 0.059 100.2 Jim Wells/48249 169.2 0.461 231.9 0.632 3.9 0.010 3.8 0.010 9.1 Johnson/48251 997.6 2.711 1667.9 4.532 32.6 0.089 32.2 0.088 110.7 Jones/48253 22.5 0.061 64.0 0.174 1.0 0.003 1.0 0.003 6.4 Karnes/48255 178.7 0.487 283.6 0.772 4.7 0.013 4.7 0.013 15.9 Kaufman/48257 0.1 0.000 0.2 0.001 0.0 0.000 0.0 0.000 0.0 Kendall/48259 Kenedy/48261 1169.9 3.186 1900.3 5.175 32.8 0.089 32.6 0.089 81.6 Kent/48263 139.3 0.379 161.5 0.440 2.5 0.007 2.5 0.007 1.4 Kerr/48265 0.0 0.000 0.0 0.000 Kimble/48267 7.4 0.020 14.3 0.039 0.2 0.001 0.2 0.001 1.0 King/48269 50.7 0.138 108.1 0.294 1.7 0.005 1.7 0.005 7.9 Kinney/48271 Kleberg/48273 637.7 1.737 955.5 2.602 16.5 0.045 16.5 0.045 31.6 Knox/48275 1.0 0.003 4.4 0.012 0.1 0.000 0.1 0.000 0.4 Lamar/48277 Lamb/48279 3.6 0.010 5.3 0.015 0.1 0.000 0.1 0.000 0.0 Lampasas/48281 0.4 0.001 1.7 0.005 0.0 0.000 0.0 0.000 0.2 La Salle/48283 788.5 2.147 2652.1 7.223 44.2 0.120 43.3 0.118 277.5 Lavaca/48285 1276.2 3.476 1778.0 4.842 29.5 0.080 29.3 0.080 73.8 Lee/48287 272.3 0.742 446.0 1.215 7.3 0.020 7.3 0.020 34.6 Leon/48289 1200.3 3.269 2879.0 7.840 47.9 0.130 47.1 0.128 250.3 Liberty/48291 533.8 1.456 1098.5 2.996 26.2 0.072 26.0 0.071 77.7 Limestone/48293 1402.9 3.821 2251.7 6.132 37.5 0.102 37.1 0.101 125.4 Lipscomb/48295 993.5 2.706 1558.9 4.246 25.9 0.070 25.6 0.070 88.5 Live Oak/48297 878.9 2.394 2504.9 6.822 41.7 0.114 41.0 0.112 241.5 Llano/48299 
3

-38

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Loving/48301 1338.5 3.645 2187.1 5.956 36.3 0.099 35.9 0.098 127.3 Lubbock/48303 10.3 0.028 39.9 0.109 0.6 0.002 0.6 0.002 3.9 Lynn/48305 7.2 0.020 28.6 0.078 0.5 0.001 0.5 0.001 3.2 McCulloch/48307 8.4 0.023 35.4 0.096 0.6 0.002 0.6 0.002 4.0 McLennan/48309 0.0 0.000 0.0 0.000 McMullen/48311 1262.6 3.438 2237.0 6.092 37.1 0.101 36.7 0.100 147.0 Madison/48313 152.2 0.414 256.4 0.698 4.3 0.012 4.2 0.011 16.0 Marion/48315 106.2 0.289 180.1 0.491 3.0 0.008 3.0 0.008 11.3 Martin/48317 294.6 0.802 709.4 1.932 11.6 0.032 11.4 0.031 61.0 Mason/48319 Matagorda/48321 1009.0 2.748 1847.6 5.032 32.6 0.089 32.4 0.088 83.1 Maverick/48323 222.8 0.607 721.6 1.965 12.0 0.033 11.8 0.032 74.3 Medina/48325 1.4 0.004 5.5 0.015 0.1 0.000 0.1 0.000 0.6 Menard/48327 4.3 0.012 13.0 0.035 0.2 0.001 0.2 0.001 1.2 Midland/48329 1153.9 3.143 2082.1 5.670 34.3 0.093 33.8 0.092 135.2 Milam/48331 10.7 0.029 25.8 0.070 0.4 0.001 0.4 0.001 2.1 Mills/48333 12.3 0.034 53.0 0.144 0.9 0.002 0.9 0.002 6.0 Mitchell/48335 33.3 0.091 120.6 0.328 1.9 0.005 1.8 0.005 12.1 Montague/48337 147.0 0.400 508.6 1.385 8.4 0.023 8.3 0.022 55.0 Montgomery/48339 95.1 0.259 229.9 0.627 5.1 0.014 5.1 0.014 18.4 Moore/48341 695.2 1.893 766.2 2.087 12.7 0.035 12.7 0.035 8.6 Morris/48343 0.0 0.000 0.0 0.000 Motley/48345 0.0 0.000 0.1 0.000 0.0 0.000 0.0 0.000 0.0 Nacogdoches/48347 1283.4 3.495 1971.3 5.368 32.7 0.089 32.4 0.088 104.8 Navarro/48349 22.7 0.062 67.8 0.185 1.1 0.003 1.1 0.003 6.8 Newton/48351 95.2 0.259 227.7 0.620 3.8 0.010 3.7 0.010 21.8 Nolan/48353 47.9 0.130 102.2 0.278 1.7 0.004 1.6 0.004 7.8 Nueces/48355 1322.6 3.605 2168.4 5.911 36.6 0.100 36.3 0.099 112.0 Ochiltree/48357 499.0 1.359 668.7 1.821 11.1 0.030 11.0 0.030 25.2 Oldham/48359 3.6 0.010 3.8 0.010 0.1 0.000 0.1 0.000 0.0 
3

-39

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Orange/48361 141.7 0.385 260.4 0.708 5.7 0.015 5.6 0.015 16.5 Palo Pinto/48363 248.1 0.676 308.2 0.839 5.1 0.014 5.1 0.014 9.4 Panola/48365 4987.1 13.581 7101.1 19.338 118.0 0.321 117.0 0.319 313.8 Parker/48367 407.1 1.106 944.1 2.565 17.4 0.047 17.1 0.047 82.5 Parmer/48369 Pecos/48371 3156.7 8.597 3859.0 10.509 63.8 0.174 63.5 0.173 94.7 Polk/48373 384.7 1.048 506.6 1.380 8.4 0.023 8.3 0.023 17.0 Potter/48375 295.6 0.805 420.3 1.145 7.0 0.019 6.9 0.019 17.9 Presidio/48377 Rains/48379 90.5 0.246 92.7 0.252 1.5 0.004 1.5 0.004 0.0 Randall/48381 Reagan/48383 938.3 2.555 2606.4 7.098 43.3 0.118 42.5 0.116 248.4 Real/48385 8.0 0.022 9.5 0.026 0.2 0.000 0.2 0.000 0.2 Red River/48387 0.1 0.000 0.4 0.001 0.0 0.000 0.0 0.000 0.0 Reeves/48389 502.9 1.369 767.4 2.090 12.8 0.035 12.6 0.034 38.3 Refugio/48391 837.2 2.280 1057.7 2.880 17.4 0.047 17.3 0.047 34.5 Roberts/48393 733.6 1.998 1231.6 3.354 20.4 0.056 20.2 0.055 78.0 Robertson/48395 2415.4 6.578 4231.1 11.522 70.4 0.192 69.5 0.189 269.3 Rockwall/48397 Runnels/48399 61.7 0.168 183.3 0.499 3.0 0.008 3.0 0.008 18.9 Rusk/48401 1906.2 5.260 3188.9 8.799 52.9 0.146 52.3 0.144 192.1 Sabine/48403 3.3 0.009 12.6 0.034 0.2 0.001 0.2 0.001 1.4 San Augustine/48405 0.5 0.001 0.5 0.001 0.0 0.000 0.0 0.000 0.0 San Jacinto/48407 122.2 0.333 214.0 0.584 3.6 0.010 3.5 0.010 13.5 San Patricio/48409 680.1 1.854 1279.7 3.488 21.3 0.058 21.0 0.057 88.0 San Saba/48411 Schleicher/48413 255.2 0.695 382.5 1.042 6.3 0.017 6.2 0.017 20.6 Scurry/48415 523.8 1.427 899.6 2.450 14.3 0.039 14.1 0.039 55.5 Shackelford/48417 64.3 0.175 105.9 0.289 1.7 0.005 1.7 0.005 5.9 
3

-40

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Shelby/48419 712.7 1.941 996.8 2.714 16.6 0.045 16.4 0.045 43.3 Sherman/48421 357.4 0.973 388.0 1.057 6.5 0.018 6.4 0.018 3.5 Smith/48423 2082.9 5.748 6012.6 16.591 100.0 0.276 98.2 0.271 591.0 Somervell/48425 4.8 0.013 13.9 0.038 0.2 0.001 0.2 0.001 1.4 Starr/48427 2203.1 6.000 2580.6 7.028 42.7 0.116 42.6 0.116 54.7 Stephens/48429 229.5 0.625 331.2 0.902 5.4 0.015 5.4 0.015 14.4 Sterling/48431 315.7 0.860 490.1 1.335 8.1 0.022 8.0 0.022 25.9 Stonewall/48433 13.3 0.036 32.4 0.088 0.5 0.001 0.5 0.001 2.5 Sutton/48435 1397.6 3.806 1619.6 4.411 26.9 0.073 26.8 0.073 30.8 Swisher/48437 Tarrant/48439 1613.3 4.384 2394.1 6.506 49.0 0.133 48.6 0.132 126.4 Taylor/48441 5.5 0.015 11.4 0.031 0.2 0.000 0.2 0.000 1.0 Terrell/48443 1188.8 3.238 1591.4 4.334 26.5 0.072 26.3 0.072 58.6 Terry/48445 54.7 0.149 166.2 0.453 2.6 0.007 2.6 0.007 15.4 Throckmorton/48447 31.0 0.085 50.8 0.138 0.8 0.002 0.8 0.002 2.8 Titus/48449 1.6 0.004 7.0 0.019 0.1 0.000 0.1 0.000 0.7 Tom Green/48451 109.7 0.299 337.7 0.920 5.6 0.015 5.5 0.015 33.9 Travis/48453 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Trinity/48455 3.6 0.010 4.5 0.012 0.1 0.000 0.1 0.000 0.1 Tyler/48457 604.0 1.645 1576.4 4.293 26.2 0.071 25.7 0.070 144.8 Upshur/48459 1075.2 2.967 1860.8 5.135 31.0 0.085 30.6 0.084 115.4 Upton/48461 1835.0 4.997 3749.9 10.212 62.0 0.169 61.1 0.166 288.0 Uvalde/48463 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Val Verde/48465 358.2 0.976 571.2 1.555 9.5 0.026 9.4 0.026 31.2 Van Zandt/48467 121.3 0.330 138.9 0.378 2.3 0.006 2.3 0.006 2.0 Victoria/48469 375.7 1.023 465.2 1.267 7.7 0.021 7.7 0.021 12.9 Walker/48471 27.8 0.076 59.5 0.162 1.0 0.003 1.0 0.003 4.9 Waller/48473 60.5 0.165 174.4 0.476 3.5 0.009 3.4 0.009 16.9 Ward/48475 1005.2 2.737 1757.6 4.786 29.1 0.079 28.8 0.078 110.5 Washington/48477 476.9 1.299 638.8 1.740 10.6 0.029 10.5 0.029 24.0 
3

-41

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Webb/48479 4544.7 12.377 6660.3 18.138 110.7 0.301 109.7 0.299 313.3 Wharton/48481 1128.5 3.073 1806.8 4.920 30.0 0.082 29.6 0.081 100.9 Wheeler/48483 3263.5 8.888 10568.9 28.782 176.2 0.480 172.7 0.470 1090.9 Wichita/48485 19.4 0.053 72.0 0.196 1.1 0.003 1.1 0.003 7.2 Wilbarger/48487 40.2 0.109 174.1 0.474 2.9 0.008 2.8 0.008 19.7 Willacy/48489 505.1 1.376 661.2 1.801 10.9 0.030 10.9 0.030 22.6 Williamson/48491 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Wilson/48493 8.0 0.022 33.3 0.091 0.5 0.001 0.5 0.001 3.7 Winkler/48495 811.0 2.209 1430.0 3.894 23.7 0.064 23.4 0.064 92.8 Wise/48497 3384.1 9.196 5251.0 14.269 87.3 0.237 86.4 0.235 280.0 Wood/48499 225.5 0.614 268.3 0.731 4.3 0.012 4.3 0.012 4.5 Yoakum/48501 558.2 1.520 1000.9 2.726 15.6 0.043 15.4 0.042 60.1 Young/48503 65.9 0.179 104.4 0.284 1.7 0.005 1.7 0.005 5.3 Zapata/48505 6054.2 16.488 9233.8 25.147 153.4 0.418 151.9 0.414 476.8 Zavala/48507 66.7 0.182 217.9 0.593 3.6 0.010 3.5 0.010 22.3 Brazos, Block 376 13.3 0.036 8.8 0.024 0.1 0.000 0.1 0.000 0.0 Brazos, Block 397 127.1 0.346 82.2 0.224 0.3 0.001 0.3 0.001 0.0 Brazos, Block 415 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Brazos, Block 451 245.2 0.668 158.9 0.433 0.7 0.002 0.7 0.002 0.0 Brazos, Block 453 139.6 0.380 91.6 0.249 0.4 0.001 0.4 0.001 2.0 Brazos, Block 491 21.9 0.060 14.2 0.039 0.1 0.000 0.1 0.000 0.0 Brazos, Block 542 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Galveston, Block 190 17.6 0.048 16.6 0.045 0.4 0.001 0.4 0.001 0.0 Galveston, Block 209 116.3 0.317 271.8 0.740 4.7 0.013 4.7 0.013 0.1 Galveston, Block 223 10.3 0.028 15.6 0.043 0.0 0.000 0.0 0.000 0.0 Galveston, Block 225 Galveston, Block 239 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Galveston, Block 255 29.1 0.079 19.3 0.053 0.1 0.000 0.1 0.000 0.0 Galveston, Block 273 95.0 0.259 68.6 0.187 0.8 0.002 0.8 0.002 0.0 Galveston, Block 301 10.0 0.027 7.3 0.020 0.0 0.000 0.0 0.000 0.0 
3

-42

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Galveston, Block 303 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Galveston, Block 333 2.5 0.007 10.7 0.029 0.7 0.002 0.7 0.002 0.0 Galveston, Block 343 84.6 0.231 56.9 0.155 0.0 0.000 0.0 0.000 0.1 Galveston, Block 395 10.3 0.028 6.9 0.019 0.0 0.000 0.0 0.000 0.0 High Island, Block 021 High Island, Block 022 36.5 0.099 23.6 0.064 0.1 0.000 0.1 0.000 0.0 High Island, Block 034 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 High Island, Block 037 0.2 0.001 0.3 0.001 0.0 0.000 0.0 0.000 0.0 High Island, Block 039 59.4 0.162 38.4 0.105 0.2 0.000 0.2 0.000 0.0 High Island, Block 045 122.9 0.335 79.5 0.217 0.3 0.001 0.3 0.001 0.0 High Island, Block 046 3.2 0.009 2.2 0.006 0.0 0.000 0.0 0.000 0.0 High Island, Block 052 15.3 0.042 9.9 0.027 0.0 0.000 0.0 0.000 0.0 High Island, Block 072 High Island, Block 084 7.8 0.021 11.9 0.032 0.0 0.000 0.0 0.000 0.0 High Island, Block 085 148.8 0.405 96.3 0.262 0.4 0.001 0.4 0.001 0.0 High Island, Block 110 56.6 0.154 37.7 0.103 0.2 0.001 0.2 0.001 0.0 High Island, Block 116 67.5 0.184 44.0 0.120 0.2 0.001 0.2 0.001 0.0 High Island, Block 136 123.2 0.335 82.0 0.223 0.5 0.001 0.5 0.001 0.0 High Island, Block 140 39.9 0.109 26.2 0.071 0.1 0.000 0.1 0.000 0.0 High Island, Block 154 12.4 0.034 13.6 0.037 0.2 0.001 0.2 0.001 0.0 High Island, Block 176 274.5 0.748 179.0 0.487 0.9 0.002 0.9 0.002 0.0 High Island, Block 177 96.2 0.262 79.3 0.216 0.9 0.002 0.9 0.002 0.0 High Island, Block 179 172.3 0.469 115.8 0.315 0.5 0.001 0.5 0.001 0.0 High Island, Block 194 Matagorda Island, Block 487 65.0 0.177 42.1 0.115 0.2 0.000 0.2 0.000 0.0 Matagorda Island, Block 555 112.6 0.307 75.0 0.204 0.5 0.001 0.5 0.001 0.0 Matagorda Island, Block 566 2.8 0.008 4.3 0.012 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 587 153.6 0.418 99.5 0.271 0.4 0.001 0.4 0.001 0.0 Matagorda Island, Block 588 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 603 0.6 0.002 0.4 0.001 0.0 0.000 0.0 0.000 0.0 
3

-43

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

Matagorda Island, Block 604 219.7 0.598 144.6 0.394 0.8 0.002 0.8 0.002 0.0 Matagorda Island, Block 605 69.0 0.188 44.7 0.122 0.2 0.001 0.2 0.001 0.0 Matagorda Island, Block 618 31.1 0.085 29.4 0.080 0.1 0.000 0.1 0.000 0.0 Matagorda Island, Block 622 173.7 0.473 192.0 0.523 1.3 0.004 1.3 0.004 4.4 Matagorda Island, Block 623 187.7 0.511 127.0 0.346 1.0 0.003 1.0 0.003 0.0 Matagorda Island, Block 631 145.3 0.396 94.1 0.256 0.4 0.001 0.4 0.001 0.0 Matagorda Island, Block 632 180.7 0.492 117.6 0.320 0.5 0.001 0.5 0.001 0.1 Matagorda Island, Block 633 32.4 0.088 39.9 0.109 0.1 0.000 0.1 0.000 0.0 Matagorda Island, Block 635 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 638 74.8 0.204 48.4 0.132 0.2 0.001 0.2 0.001 0.0 Matagorda Island, Block 657 1.4 0.004 6.4 0.017 0.5 0.001 0.5 0.001 0.0 Matagorda Island, Block 685 1.2 0.003 1.9 0.005 0.0 0.000 0.0 0.000 0.0 Matagorda Island, Block 686 150.9 0.411 98.9 0.269 0.5 0.001 0.5 0.001 0.0 Matagorda Island, Block 696 63.7 0.174 41.3 0.112 0.2 0.000 0.2 0.000 0.0 Matagorda Island, Block 699 72.7 0.198 47.2 0.129 0.2 0.001 0.2 0.001 0.0 Mustang Island, Block 726 0.4 0.001 0.7 0.002 0.0 0.000 0.0 0.000 0.0 Mustang Island, Block 754 3.2 0.009 4.9 0.013 0.0 0.000 0.0 0.000 0.0 Mustang Island, Block 858 1.9 0.005 2.9 0.008 0.0 0.000 0.0 0.000 0.0 Sabine Pass-Louisiana, Block 006 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 Sabine Pass-Louisiana, Block 010 162.3 0.442 105.3 0.287 0.5 0.001 0.5 0.001 0.0 Sabine Pass-Louisiana, Block 012 0.4 0.001 0.5 0.001 0.0 0.000 0.0 0.000 0.0 Sabine Pass-Louisiana, Block 013 272.9 0.743 185.3 0.505 1.5 0.004 1.5 0.004 0.0 Sabine Pass-Texas, Block 018 69.0 0.188 44.7 0.122 0.2 0.001 0.2 0.001 0.0 West Cameron, Block 021 0.0 0.000 0.1 0.000 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 022 0.6 0.002 0.8 0.002 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 043 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 044 49.3 0.134 57.0 0.155 2.2 0.006 2.2 0.006 0.0 
3

-44

Table 3-5. Combined County-Level Emission Estimates for All Sources Included in the Invento

COANN CO- OSD NOX- ANN NOX- OSD PM10- ANN PM10- OSD PM2.5- ANN PM2.5- OSD SO2- ANN 

Texas County/FIPS tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr tons/day tons/yr t

West Cameron, Block 045 5.0 0.014 3.3 0.009 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 048 151.6 0.413 99.5 0.271 0.4 0.001 0.4 0.001 0.0 West Cameron, Block 053 20.3 0.055 19.1 0.052 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 116 0.0 0.000 0.0 0.000 0.0 0.000 0.0 0.000 0.0 West Cameron, Block 130 7.8 0.021 8.8 0.024 0.3 0.001 0.3 0.001 0.0 West Cameron, Block 153 

Total 125,968 343.31 221,357 603.37 3,711 10.11 3,667 9.99 14,064 

In order to reflect significant figures, estimates should be interpreted as follows: 0.0 = <0.1; 0.00 = <0.01; and 0.000 = <0.0
3-45 

When considering only VOC emissions, the county distribution for onshore exploration is 

somewhat different as illustrated below. These 14 counties constitute 26.6% of total statewide 

VOC from oil and gas onshore exploration area sources. 

 Andrews (2.76%) 

 Ector (2.39%) 

 Crockett (2.18%) 

 Wichita (2.16%) 

 Hemphill (2.16%) 

 Midland (1.98%) 

 Upton (1.79%) 

 Zapata (1.78%) 

 Crane (1.58%) 

 Panola (1.58%) 

 Yoakum (1.57%) 

 Gaines (1.57%) 

 Wheeler (1.55%) 

 Wise (1.53%) 

For all other counties for VOC, emission contributions are less than 1.5%. 

3.3.2 Onshore Production 

Annual and OSD emissions for all pollutants are presented at the county level for onshore 

production sources collectively in Table 3-4b. Considering only VOC emissions, 18 counties are 

responsible for nearly 40% of statewide emissions from oil and gas area sources. The ranking of 

these counties for VOC for onshore production is as follows. 

 Hidalgo (3.5%) 

 Panola (3.4%)

 Webb (2.85%)

 Zapata (2.72%)

 Freestone (2.34%)

 Pecos (2.25%)

 Starr (2.24%)

 Upton (2.22%)

 Liberty (2.13%)

 Wise (1.92%)

 Denton (1.7%)

 Andrews (1.7%)

 Gaines (1.67%)

 Jefferson (1.66%)

 Tyler (1.61%)

 Hemphill (1.58%)

 Ector (1.52%)

 Crockett (1.51%)
3-46 

All other counties contribute less than 1.5% and the majority are below 1%. 

In looking at the remaining pollutants that mainly come from onshore production 

combustion sources, a total of 13 counties constitute over 41% of all other pollutant emissions 

(i.e., CO, NOx, PM10, PM2.5 and SO2). For any one of these pollutants, the primary county 

contributors are in order (note: to illustrate the relative contribution levels, the values for NOx are 

shown below, values for the other pollutants follow similar relative tracks): 

 Zapata (5.50%) 

 Freestone (4.80%) 

 Panola (4.77%) 

 Webb (4.26%) 

 Hidalgo (3.72%) 

 Pecos (3.31%) 

 Wise (3.09%) 

 Starr (2.29%) 

 Crockett (2.07%) 

 Robertson (2.04%) 

 Hemphill (1.92%) 

 Denton (1.76%) 

 Rusk (1.64%) 

3.3.3 Offshore Production Sources 

County- and lease block-level emission estimates for offshore production platforms are 

provided in Table 3-4c. As described previously, offshore sources are divided into two groups – 

state waters (coastline out to 10 miles) and federal waters (from 10 to 25 miles from shore). For 

VOC emissions, the majority of emissions were shown to occur from state waters sources. The 

principal counties and their percent contribution to total offshore VOC emissions is shown 

below. These nine counties comprise roughly 78% of the estimated offshore VOC emissions. 

 Kenedy (17.8%) 

 Galveston (15.9%) 

 Jefferson (12.3%) 

 Calhoun (7.2%) 

 Matagorda (7.0%) 

 Brazoria (5.7%) 

 Kleberg (5.6%) 

 Nueces (4.1%) 

 Aransas (2.3%) 

In the federal waters offshore area, only four lease blocks had VOC emissions 

constituting at least 1% of total offshore emissions. These blocks include Matagorda IslandBlock 555 (1.61%), Matagorda Island-Block 622 (1.58%), High Island-Block 176 (1.37%), and 

Galveston-Block 209 (1.0%). All other counties and lease blocks were less than 1% of total 

VOC emissions. 
3-47 

For combustion–related pollutants, the picture is similar, but with some differences. For 

pollutants like NOX , CO, and SO2, Jefferson County (state waters) is shown to be the primary 

source of emissions (CO-10.2%, NOX-17.7%, PM10- 22.9%, and SO2-28.2%). After Jefferson, 

the main contributors to combustion pollutant emissions were Calhoun, Matagorda, Galveston, 

and Brazoria. These all occur in state waters. The contribution of sources in state waters (in 

these 5 to 7 counties) to total emissions of these pollutants is as follows. 

 CO – 36.6% 

 NOx – 62.8% 

 PM10 – 81.5% 

 PM2.5 – 81.4% 

 SO2 – 96% 

In federal waters, most of the contributions for lease blocks for combustion-related 

pollutants are less than 1%. However, there are some exceptions for specific pollutants. For CO, 

the following lease blocks have significant contributions. 

 High Island-Block176 (3.75%) 

 Sabine Pass-Louisiana-Block 013 (3.73%) 

 Brazos-Block 451 (3.35%) 

 Matagorda Island-Block 623 (2.56%) 

 Matagorda Island-Block 622 (2.37%) 

 High Island-Block 179 (2.35%) 

Galveston-Block 209, Matagorda Island-Block 622, and Sabine Pass-Louisiana-Block 013 are 

significant contributors for NOx, PM10, and PM2.5. 

3.4 Comparison of Emissions by Attainment Status 

The inventory data results were analyzed to evaluate how much of each pollutant 

emission was occurring in counties classified as attainment and nonattainment (for any 

pollutant). All counties were assigned an attainment status based on information from the TCEQ 

web site and the U.S. EPA (US EPA, 2007) and all pollutant emissions were summed by county

based on its classification. The results of that assessment are summarized in Table 3-6. 
3-48 

Table 3-6. Summary of Oil and Gas Area Source Emissions by Attainment Status 

Pollutant Attainment Status Total Emissions (tons/yr) Percent of Total 

CO Attainment Counties 119,116 94.6% 

Nonattainment Counties 6,851 5.4% 

NOx Attainment Counties 208,250 94.1% 

Nonattainment Counties 13,107 5.9% 

VOC Attainment Counties 756,676 89.9% 

Nonattainment Counties 84,619 10.1% 

SO2 Attainment Counties 13,271 94.4% 

Nonattainment Counties 792 5.6% 

PM10 Attainment Counties 3,437 92.6% 

Nonattainment Counties 274 7.4% 

PM2.5 Attainment Counties 3,395 92.6% 

Nonattainment Counties 271 7.4% 

As indicated in Table 3-6, for every pollutant, attainment counties contain the bulk of the 

emissions. Given the shear number of total counties in Texas and the relatively low number of 

nonattainment counties, this result is not unexpected. 
4-1 

4.0 EMISSIONS PROJECTIONS 

4.1 Projections Methodology 

Statewide emission projections were developed for base years 2010, 2015, and 2020 

using information from the Energy Information Administration’s (EIA) Supplemental Tables to 

the Annual Energy Outlook (EIA, 2007). The EIA data tables (specifically Tables 103 and 104) 

present annual estimated crude oil and natural gas for the years 2004-2030. The geographic level 

of the projected data is by EIA Region. 

Portions of Texas fall into three EIA Regions: Gulf Coast; Southwest; and Midcontinent. 

The majority of the State is in the Gulf Coast and Southwest EIA Regions. Only a small portion 

(area to the west of Oklahoma) is in the Midcontinent Region. Because the Midcontinent EIA 

Region contains six other states, any projections data for the Midcontinent EIA Region may not 

be reflective of Texas operations. Thus, it was assumed that the Southwest EIA Region is likely 

more representative of the Texas portion of the Midcontinent EIA Region. 

Similarly, the Gulf Coast EIA Region includes mostly east Texas counties, but also 

includes four other states. The Southwest EIA Region includes almost all of west Texas, and the 

eastern half of New Mexico. The EIA data also has projections for offshore platforms that are 

“Offshore-shallow” and “Offshore-deep.” It was assumed that the “Offshore-shallow” EIA 

Region is a suitable surrogate for platforms in Texas state waters and the “Offshore-deep” EIA 

Region is a suitable surrogate for platforms in federal waters. Tables 4-1(a-d) identify the Texas 

counties with the appropriate EIA Region. 

Tables 4-2(a-c) present the steps for developing the projected oil and natural gas 

production for 2010, 2015, and 2020. Projection factors for each year were developed and 

applied to the counties in the applicable EIA Region, and summed together. Additionally, only

one projection factor was developed to account for all oil and gas operations. Thus, the oil and 

natural gas production data were converted to BTU and then summed together. 

For example, year 2005 oil production for the “Onshore-Gulf Coast” EIA Region was 

0.54 million barrels (MMBBL) per day. Using an average heating value of 134,010 BTU/gal for 

crude oil, this equates to 1.11 billion MMBTU. The year 2005 natural gas production for the 

same region was 4.65 trillion cubic feet. Using an average heating value of 1036 BTU/scf, this 

equates to 4.82 billion MMBTU. Summing the oil and natural gas production yields a total of

5.93 billion MMBTU. In 2010, the same data parameters yield 0.719 billion MMBTU for oil 

and 4.64 billion MMBTU for natural gas. The total for year 2010 is 5.36 billion MMBTU. 

Therefore, the projection factor from 2005 to 2010 is: 

2005 to 2010 projection factor = 2010 total MMBTU/2005 total MMBTU 

2005 to 2010 projection factor = 5.36 billion MMBTU/5.93 billion MMBTU 

2005 to 2010 projection factor = 0.90 
4-2 

Table 4-1a. Texas Counties in the Onshore-Gulf Coast EIA Region 

Anderson Franklin Lavaca Sabine 

Angelina Freestone Lee San Augustine 

Aransas Frio Leon San Jacinto 

Atascosa Galveston Liberty San Patricio 

Austin Goliad Limestone Shelby 

Bastrop Gonzales Live Oak Smith 

Bee Gregg Martin Starr 

Bexar Grimes Matagorda Titus 

Bowie Guadalupe Mclennan Travis 

Brazoria Hardin Mcmullen Trinity 

Brazos Harris Medina Tyler 

Brooks Harrison Milam Upshur 

Burleson Henderson Montgomery Uvalde 

Caldwell Hidalgo Morris Van Zandt 

Calhoun Hopkins Nacogdoches Victoria 

Cameron Houston Navarro Walker 

Camp Jackson Newton Waller 

Cass Jasper Nueces Washington 

Chambers Jefferson Orange Webb 

Cherokee Jim Hogg Panola Wharton 

Colorado Jim Wells Polk Willacy 

Denton Karnes Rains Williamson 

Dimmit Kaufman Red River Wilson 

Duval Kenedy Refugio Wood 

Falls Kleberg Robertson Zapata 

Fayette La Salle Rusk Zavala 

Fort Bend Lampasas 
4-3 

Table 4-1b. Texas Counties in the Onshore-Southwest EIA Region 

Andrews Edwards Kimble Roberts 

Archer Ellis King Runnels 

Bandera Erath Knox Schleicher 

Baylor Fisher Lamb Scurry 

Borden Floyd Lipscomb Shackelford 

Bosque Foard Loving Sherman 

Brown Gaines Lubbock Somervell 

Callahan Garza Lynn Stephens 

Carson Glasscock Madison Sterling 

Childress Gray Marion Stonewall 

Clay Grayson Maverick Sutton 

Cochran Hale Mcculloch Tarrant 

Coke Hamilton Menard Taylor 

Coleman Hansford Midland Terrell 

Collingsworth Hardeman Mills Terry 

Comanche Hartley Mitchell Throckmorton 

Concho Haskell Montague Tom Green 

Cooke Hemphill Moore Upton 

Cottle Hill Motley Val Verde 

Crane Hockley Nolan Ward 

Crockett Hood Ochiltree Wheeler 

Crosby Howard Oldham Wichita 

Culberson Hutchinson Palo Pinto Wilbarger 

Dawson Irion Parker Winkler 

De Witt Jack Pecos Wise 

Dickens Johnson Potter Yoakum 

Donley Jones Reagan Young 

Eastland Kent Real 

Ector Kerr Reeves 

Table 4-1c. Texas Counties in the Offshore-Shallow EIA Region 

Aransas Jefferson 

Brazoria Kenedy 

Calhoun Kleberg 

Chambers Matagorda 

Galveston Nueces 
4-4 

Table 4-1d. Area-Blocks in the Offshore-Deep EIA Region 

Brazos, Block 376 High Island, Block 052 Matagorda Island, Block 633 

Brazos, Block 397 High Island, Block 072 Matagorda Island, Block 635 

Brazos, Block 415 High Island, Block 084 Matagorda Island, Block 638 

Brazos, Block 451 High Island, Block 085 Matagorda Island, Block 657 

Brazos, Block 453 High Island, Block 110 Matagorda Island, Block 685 

Brazos, Block 491 High Island, Block 116 Matagorda Island, Block 686 

Brazos, Block 542 High Island, Block 136 Matagorda Island, Block 696 

Galveston, Block 190 High Island, Block 140 Matagorda Island, Block 699 

Galveston, Block 209 High Island, Block 154 Mustang Island, Block 726 

Galveston, Block 223 High Island, Block 176 Mustang Island, Block 754 

Galveston, Block 225 High Island, Block 177 Mustang Island, Block 858 

Galveston, Block 239 High Island, Block 179 Sabine Pass-Louisiana, Block 006 

Galveston, Block 255 High Island, Block 194 Sabine Pass-Louisiana, Block 010 

Galveston, Block 273 Matagorda Island, Block 487 Sabine Pass-Louisiana, Block 012

Galveston, Block 301 Matagorda Island, Block 555 Sabine Pass-Louisiana, Block 013

Galveston, Block 303 Matagorda Island, Block 566 Sabine Pass-Texas, Block 018 

Galveston, Block 333 Matagorda Island, Block 587 West Cameron, Block 021 

Galveston, Block 343 Matagorda Island, Block 588 West Cameron, Block 022 

Galveston, Block 395 Matagorda Island, Block 603 West Cameron, Block 043 

High Island, Block 021 Matagorda Island, Block 604 West Cameron, Block 044 

High Island, Block 022 Matagorda Island, Block 605 West Cameron, Block 045 

High Island, Block 034 Matagorda Island, Block 618 West Cameron, Block 048 

High Island, Block 037 Matagorda Island, Block 622 West Cameron, Block 053 

High Island, Block 039 Matagorda Island, Block 623 West Cameron, Block 116 

High Island, Block 045 Matagorda Island, Block 631 West Cameron, Block 130 

High Island, Block 046 Matagorda Island, Block 632 West Cameron, Block 153 
4-5 

Table 4-2a. Projected EIA Production 

Oil Production Natural Gas Production 

2005 2010 2015 2020 2005 2010 2015 2020 

Location (MMBBL/day) TSCF 

Offshore-Deep 0.84 1.62 1.98 1.85 1.37 2.27 3.05 2.68 

Offshore-Shallow 0.47 0.34 0.3 0.32 1.98 1.59 1.49 1.39 

Onshore-Gulf Coast 0.54 0.35 0.27 0.27 4.65 4.48 4.11 3.94 

Onshore-Southwest 0.93 0.93 0.91 0.9 1.81 2.02 1.95 1.9 

Table 4-2b. Projected EIA Production (MMBTU) 

Oil Production Natural Gas Production 

2005 2010 2015 2020 2005 2010 2015 2020 

Location Billion MMBTU Billion MMBTU 

Offshore-Deep 1.73 3.33 4.07 3.80 1.42 2.35 3.16 2.78 

Offshore-Shallow 0.97 0.70 0.62 0.66 2.05 1.65 1.54 1.44 

Onshore-Gulf Coast 1.11 0.72 0.55 0.55 4.82 4.64 4.26 4.08 

Onshore-Southwest 1.91 1.91 1.87 1.85 1.88 2.09 2.02 1.97 

Table 4-2c. Final Projection Factors by EIA Region

Total Oil and Natural Gas 

Production Projection Factors from 2005 

2005 2010 2015 2020 2005 2010 2015 2020 

Location Billion MMBTU Unitless 

Offshore-Deep 3.14 5.68 7.23 6.58 1.00 1.81 2.30 2.09 

Offshore-Shallow 3.02 2.35 2.16 2.10 1.00 0.78 0.72 0.70 

Onshore-Gulf Coast 5.93 5.36 4.81 4.64 1.00 0.90 0.81 0.78 

Onshore-Southwest 3.79 4.00 3.89 3.82 1.00 1.06 1.03 1.01 

4.2 Summary of Oil and Gas Area Sources Projected Emissions 

Tables 4-3(a-f) are summaries of the projected statewide emissions by location (onshore, 

offshore), type (exploration, production, and offshore), and pollutant. Generally, emissions are 

projected to decline from 2005 to 2020 for onshore production (~14%), onshore exploration 

(~11%), and offshore-state waters (~30%). Conversely, emissions from offshore-federal waters 

are projected to increase during the same time period (~109%). 
4-6 

Table 4-3a. CO Projected Emissions by Location and Type

Pollutant Location Type 

2005 

Emissions 

(tpy) 

2010 

Emissions 

(tpy) 

2015 

Emissions 

(tpy) 

2020 

Emissions 

(tpy) 

CO Onshore Exploration 29,695 29,021 27,209 26,462 

CO Onshore Production 88,949 85,299 79,260 76,919 

CO 

Offshore-Federal 

Waters Offshore 4,644 8,405 10,680 9,705 

CO Offshore-State Waters Offshore 2,680 2,090 1,929 1,876 

 Total 125,968 124,815 119,079 114,962 

Table 4-3b. NOx Projected Emissions by Location and Type

Pollutant Location Type 

2005 

Emissions 

(tpy) 

2010 

Emissions 

(tpy) 

2015 

Emissions 

(tpy) 

2020 

Emissions 

(tpy) 

NOx Onshore Exploration 120,061 117,570 110,333 107,326 

NOx Onshore Production 91,998 88,253 82,018 79,599 

NOx

Offshore-Federal 

Waters Offshore 3,457 6,257 7,951 7,225 

NOx Offshore-State Waters Offshore 5,841 4,556 4,205 4,089 

 Total 221,357 216,636 204,507 198,239 

Table 4-3c. PM10-PRI Projected Emissions by Location and Type 

Pollutant Location Type 

2005 

Emissions 

(tpy) 

2010 

Emissions 

(tpy) 

2015 

Emissions 

(tpy) 

2020 

Emissions 

(tpy) 

PM10-

PRI Onshore Exploration 1,998 1,957 1,836 1,786 

PM10-

PRI Onshore Production 1,578 1,511 1,404 1,362 

PM10-

PRI 

Offshore-Federal 

Waters Offshore 25 45 58 52 

PM10-

PRI Offshore-State Waters Offshore 110 86 79 77 

 Total 3,711 3,599 3,377 3,278 
4-7 

Table 4-3d. PM2.5-PRI Projected Emissions by Location and Type

Pollutant Location Type 

2005 

Emissions 

(tpy) 

2010 

Emissions 

(tpy) 

2015 

Emissions 

(tpy) 

2020 

Emissions 

(tpy) 

PM2.5-

PRI Onshore Exploration 1,954 1,914 1,796 1,747 

PM2.5-

PRI Onshore Production 1,578 1,511 1,404 1,362 

PM2.5-

PRI 

Offshore-Federal 

Waters Offshore 25 45 58 52 

PM2.5-

PRI Offshore-State Waters Offshore 110 86 79 77 

 Total 3,667 3,556 3,336 3,238 

Table 4-3e. SO2 Projected Emissions by Location and Type

Pollutant Location Type 

2005 

Emissions 

(tpy) 

2010 

Emissions 

(tpy) 

2015 

Emissions 

(tpy) 

2020 

Emissions 

(tpy) 

SO2 Onshore Exploration 13,835 13,552 12,719 12,373 

SO2 Onshore Production 44 42 39 38 

SO2

Offshore-Federal 

Waters Offshore 7 13 17 15 

SO2 Offshore-State Waters Offshore 177 138 128 124 

 Total 14,064 13,745 12,903 12,550 

Table 4-3f. VOC Projected Emissions by Location and Type 

Pollutant Location Type 

2005 

Emissions 

(tpy) 

2010 

Emissions 

(tpy) 

2015 

Emissions 

(tpy) 

2020 

Emissions 

(tpy) 

VOC Onshore Exploration 120,240 120,202 113,875 111,017 

VOC Onshore Production 715,941 692,079 645,543 627,048 

VOC 

Offshore-Federal 

Waters Offshore 1,088 1,970 2,503 2,274 

VOC Offshore-State Waters Offshore 4,025 3,139 2,898 2,817 

 Total 841,295 817,389 764,818 743,156 
5-1 

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2805.pdf
Appendix A – Documentation of Exploration Sources Emissions 
Appendix B – Documentation of Production Sources Emissions 
Appendix C – Documentation of Offshore Sources Emissions