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Technical Support Document (TSD): Preparation of
Emissions Inventories for the 2018v2 North American
Emissions Modeling Platform


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EPA-454/B-23-003
September 2023

Technical Support Document (TSD): Preparation of Emissions Inventories for the 2018v2 North American

Emissions Modeling Platform

U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Air Quality Assessment Division
Research Triangle Park, NC


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Authors:

Alison Eyth (EPA/OAR)
Jeff Vukovich (EPA/OAR)
Caroline Farkas (EPA/OAR)
Janice Godfrey (EPA/OAR)
Karl Seltzer (EPA/OAR)


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TABLE OF CONTENTS

LIST OF TABLES	VII

LIST OF FIGURES	X

ACRONYMS	XI

1	INTRODUCTION	14

2	BASE YEAR EMISSIONS INVENTORIES AND APPROACHES	16

2.1	Point sources (ptegu, pt_oilgas, ptnonipm, airports)	20

2.1.1	EGU sector (ptegu)	23

2.1.2	Point source oil and gas sector (pt oilgas)	25

2.1.3	Non-IPMsector (ptnonipm)	27

2.1.4	Aircraft and ground support equipment (airports)	28

2.2	Nonpoint sources (afdust, fertilizer, livestock, np_oilgas, np_sol vents, rwc, nonpt)	29

2.2.1	Area fugitive dust (afdust)	29

2.2.2	Agricultural Livestock (livestock)	34

2.2.3	Agricultural Fertilizer (fertilizer)	35

2.2.4	Nonpoint Oil and Gas (np oilgas)	38

2.2.5	Residential Wood Combustion (rwc)	39

2.2.6	Solvents (np solvents)	40

2.2.7	Nonpoint (nonpt)	41

2.3	Onroad Mobile sources (onroad)	42

2.4	Nonroad Mobile sources (cmv, rail, nonroad)	51

2.4.1	Category 1, Category 2 Commercial Marine Vessels (cmv_clc2)	51

2.4.2	Category 3 Commercial Marine Vessels (cmv_c3)	55

2.4.3	Railway Locomotives (rail)	58

2.4.4	Nonroad Mobile Equipment (nonroad)	63

2.5	Fires (ptfire-wild, ptfire-rx, ptagfire)	67

2.5.1	Wild and Prescribed Fires (ptfire-rx, ptfire-wild)	67

2.5.2	Point source Agriculture Fires (ptagfire)	71

2.6	Biogenic Sources (beis)	73

2.7	Sources Outside of the United States	74

2.7.1	Point Sources in Canada and Mexico (othpt, canadaag, canada_og2D)	75

2.7.2	Fugitive Dust Sources in Canada (othafdust, othptdust)	75

2.7.3	Nonpoint and Nonroad Sources in Canada and Mexico (othar)	76

2.7.4	Onroad Sources in Canada and Mexico (onroadcan, onroadjnex)	76

2.7.5	Fires in Canada and Mexico (ptfire othna)	76

2.7.6	Fires in Canada and Mexico (ptfire othna)	76

2.7.7	Ocean Chlorine, Ocean Sea Salt, and Volcanic Mercury	77

3	EMISSIONS MODELING	78

3.1	Emissions modeling Overview	78

3.2	Chemical Speciation	82

3.2.1	VOC speciation	85

3.2.1.1	County specific profile combinations	88

3.2.1.2	Additional sector specific considerations for integrating HAP emissions from inventories into speciation	89

3.2.1.3	Oil and gas related speciation profiles	91

3.2.1.4	Mobile source related VOC speciation profiles	93

3.2.2	PM speciation	98

3.2.2.1 Mobile source related PM2.5 speciation profiles	98

3.2.3	NO x speciation	99

3.2.4	Creation of Sulfuric Acid Vapor (SULF)	100

3.3	Temporal Allocation	101

3.3.1	Use of FF10 format for finer than annual emissions	103

3.3.2	Electric Generating Utility temporal allocation (ptegu)	103

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3.3.2.1	Base year temporal allocation of EGUs	103

3.3.2.2	Analytic year temporal allocation of EGUs	108

3.3.3	Airport Temporal allocation (airports)	113

3.3.4	Residential Wood Combustion Temporal allocation (rwc)	114

3.3.5	Agricultural Ammonia Temporal Profiles (livestock)	118

3.3.6	Oil and gas temporal allocation (npoilgas)	119

3.3.7	Onroad mobile temporal allocation (onroad)	119

3.3.8	Nonroad mobile temporal allocation(nonroad)	125

3.3.9	Additional sector specific details (afidust, beis, cmv, rail, nonpt, ptnonipm, ptfire)	126

3.4 Spatial Allocation	129

3.4.1	Spatial Surrogates for U.S. emissions	129

3.4.2	Allocation method for airport-related sources in the U.S.	136

3.4.3	Surrogates for Canada and Mexico emission inventories	136

4	ANALYTIC YEAR EMISSIONS INVENTORIES AND APPROACHES	140

4.1	EGU Point Source Projections (ptegu)	144

4.2	Sectors with Projections Computed using CoST	147

4.2.1	Background on the Control Strategy Tool (CoST)	148

4.2.2	CoST CLOSURE Packet (ptnonipm, ptoilgas)	152

4.2.3	CoST PROJECTION Packets (afidust, airports, cmv, livestock, nonpt, np oilgas, np solvents, ptnonipm, pt oilgas,
rail, rwc) 152

4.2.3.1	Fugitive dust growth (afdust)	153

4.2.3.2	Airport sources (airports)	154

4.2.3.3	Category 1, Category 2 Commercial Marine Vessels (cmv_clc2)	155

4.2.3.4	Category 3 Commercial Marine Vessels (cmv_c3)	156

4.2.3.5	Livestock population growth (livestock)	157

4.2.3.6	Nonpoint Sources (nonpt)	158

4.2.3.7	Solvents (np_solvents)	164

4.2.3.8	Oil and Gas Sources (np_oilgas, pt_oilgas)	166

4.2.3.1	Non-EGU point sources (ptnonipm)	169

4.2.3.2	Railroads (rail)	172

4.2.3.3	Residential Wood Combustion (rwc)	172

4.2.4	CoST CONTROL Packets (nonpt, np oilgas, ptnonipm, pt oilgas, np solvents)	175

4.2.4.1	Oil and Gas NSPS (np_oilgas, pt_oilgas)	176

4.2.4.2	RICE NSPS (nonpt, ptnonipm, np_oilgas, pt_oilgas)	181

4.2.4.3	Fuel Sulfur Rules (nonpt)	184

4.2.4.4	Natural Gas Turbines NOx NSPS (ptnonipm, pt_oilgas)	185

4.2.4.5	Process Heaters NOx NSPS (ptnonipm, pt_oilgas)	187

4.2.4.6	Ozone Transport Commission Rules (np_solvents)	189

4.2.4.7	Good Neighbor Plan 2015 Ozone NAAQS (ptnonipm, pt_oilgas)	190

4.3	Sectors with Projections Computed Outside of CoST	190

4.3.1	Nonroad Mobile Equipment Sources (nonroad)	190

4.3.2	Onroad Mobile Sources (onroad)	191

4.3.3	Sources Outside of the United States (onroadcan, onroadjnex, othpt, canadaag, canada_og2D, ptfire othna,
othar, othafdust, othptdust)	194

4.3.3.1	Canadian fugitive dust sources (othafdust, othptdust)	195

4.3.3.2	Point Sources in Canada and Mexico (othpt, canada_ag, canada_og2D)	195

4.3.3.3	Nonpoint sources in Canada and Mexico (othar)	196

4.3.3.4	Onroad sources in Canada and Mexico (onroad_can, onroad_mex)	197

5	EMISSION SUMMARIES	198

6	REFERENCES	202

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List of Tables

Table 2-1. Platform sectors for the 2018gg emissions modeling case	17

Table 2-2. Default stack parameter replacements	22

Table 2-3. Point source oil and gas sector NAICS Codes	25

Table 2-4. 2017-to-2018 projection factors for pt_oilgas sector	26

Table 2-5. 2017 NEI-based sources in pt oilgas (excluding offshore) before and after projections to 2018.. 27

Table 2-6. SCCs for the airports sector	28

Table 2-7. Afdust sector SCCs	29

Table 2-8. Total impact of fugitive dust adjustments to the unadjusted 2018 inventory	31

Table 2-9. SCCs for the livestock sector	34

Table 2-10. National projection factors for livestock: 2017 to 2018	35

Table 2-11. Source of input variables for EPIC	37

Table 2-12. SCCs for the residential wood combustion sector	39

Table 2-13. MOVES vehicle (source) types	43

Table 2-14. Fraction of IHS Vehicle Populations to Retain	49

Table 2-15. SCCs for cmv_clc2 sector	52

Table 2-16. Vessel groups in the cmv_clc2 sector	54

Table 2-17. SCCs for cmv_c3 sector	56

Table 2-18. Projection Factors for 2017 to 2018 for Category 3 Vessels	58

Table 2-19. SCCs for the rail sector	59

Table 2-20. 2017-to-2018 projection factors for the rail sector	59

Table 2-21. Alaska counties/census areas for which specific nonroad emissions were removed	66

Table 2-22. SCCs included in the ptfire sector	67

Table 2-23. SCCs included in the ptagfire sector	72

Table 2-24. Meteorological variables required by BEIS 3.7	73

Table 3-1. Key emissions modeling steps by sector	79

Table 3-2. Descriptions of the platform grids	81

Table 3-3. Emission model species produced for CB6R3AE7 for CMAQ	82

Table 3-4. Integration of naphthalene, benzene, acetaldehyde, formaldehyde and methanol (NBAFM) for

each sector	87

Table 3-5. Ethanol percentages by volume by Canadian province	88

Table 3-6. MOVES integrated species in M-profiles	89

Table 3-7. Basin/Region-specific profiles for oil and gas	92

Table 3-8. TOG MOVES-SMOKE Speciation Profiles for Nonroad Emissions	93

Table 3-9. Select mobile-related VOC profiles	94

Table 3-10. Onroad M-profiles	95

Table 3-11. MOVES process IDs	96

Table 3-12. MOVES Fuel subtype IDs	97

Table 3-13. MOVES regclass IDs	97

Table 3-14. Regional fire PM speciation profiles used in ptfire sectors	98

Table 3-15. Nonroad PM2.5 profiles	99

Table 3-16. NOx speciation profiles	100

Table 3-17. Sulfate split factor computation	100

Table 3-18. SO2 speciation profiles	101

Table 3-19. Temporal settings used for the platform sectors in SMOKE	102

Table 3-20. U.S. Surrogates available for this modeling platforms	130

Table 3-21. Off-Network Mobile Source Surrogates	132

Table 3-22. Spatial Surrogates for Oil and Gas Sources	132

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Table 3-23. Selected 2018 CAP emissions by sector for U.S. Surrogates (short tons in 12US1)	134

Table 3-24. Canadian Spatial Surrogates	137

Table 3-25. CAPs Allocated to Mexican and Canadian Spatial Surrogates (short tons in 36US3)	137

Table 4-1. Overview of projection methods for the analytic year cases	140

Table 4-2. EGU sector NOx emissions by State for the 2018v2 cases	146

Table 4-3. Subset of CoST Packet Matching Hierarchy	149

Table 4-4. Summary of non-EGU stationary projections subsections	150

Table 4-5. Reductions from all facility/unit/stack-level closures in 2032 from 2018 emissions levels	152

Table 4-6. Increase in PM2.5 emissions from projections in 2018v2	153

Table 4-7. TAF 2021 growth factors for major airports, 2016 to 2032	154

Table 4-8. Impact of 2016 to 2032 factors on airport emissions	155

Table 4-9. National projection factors for cmv_clc2	156

Table 4-10. California projection factors for cmv_clc2	156

Table 4-11. 2018-to-2030 CMV C3 projection factors outside of California	157

Table 4-12. 2018-to-2030 CMV C3 projection factors for California	157

Table 4-13. National projection factors for livestock: 2018 to 2032 	158

Table 4-14. Impact of 2016-2026 factors on nonpt emissions in MARAMA states	159

Table 4-15. Impact of factors on nonpt PFC emissions in MARAMA states	159

Table 4-16. Impact of 2016-2026 factors on nonpt emissions in North Carolina	159

Table 4-17. Impact of 2016-2026 factors on nonpt emissions in New Jersey	160

Table 4-18. Impact of 2016-2026 industrial factors by SCC on nonpt emissions in non-MARAMA states. 160
Table 4-19. Impact of 2026-2032 industrial factors by SCC on nonpt emissions in non-MARAMA states. 161
Table 4-20. Impact of 2026-2032 factors other than by SCC on nonpt emissions in non-MARAMA states 161

Table 4-21. Impact of factors on nonpt finished fuel emissions	162

Table 4-22. SCCs in nonpt that use Human Population Growth for Projections	162

Table 4-23. Impact of 2016-2026 population-based factors on nonpt emissions in non-MARAMA states.. 163
Table 4-24. Impact of 2026-2030 population-based factors on nonpt emissions in non-MARAMA states.. 163

Table 4-25. SCCs in npsolvents that use Human Population Growth for Projections	164

Table 4-26. Impact of population-based factors on np solvents emissions in non-MARAMA states	165

Table 4-27. Impact of factors on np_solvents emissions in MARAMA states	166

Table 4-28. Impact of 2018-2032 projections on pt_oilgas emissions	168

Table 4-29. Year 2017-2019 high-level summary of national oil and gas exploration emissions	168

Table 4-30. Impact of 2018-2032 projections on np_oilgas emissions	168

Table 4-31. Impact of 2026-2032 MARAMA projections on ptnonipm emissions	169

Table 4-32. Annual Energy Outlook (AEO) 2022 tables used to project industrial sources	170

Table 4-33. Impact of 2026-2032 industrial projections by NAICS and SCC on ptnonipm emissions	170

Table 4-34. Impact of 2026-2032 industrial projections by SCC on ptnonipm emissions	171

Table 4-35. Impact of 2026-2028 factors on ptnonipm finished fuel emissions	171

Table 4-36. Impact of 2026-2028 factors on ptnonipm biorefinery emissions	171

Table 4-37. AEO2022 growth rates for rail sub-groups, 2026 to 2032	172

Table 4-38. Impact of projections on rail emissions	172

Table 4-39. Projection factors for Residential Wood Combustion	173

Table 4-40. Impact of projections on rwc emissions, 2017-2032 	174

Table 4-41. Assumed new source emission factor ratios for NSPS rules	176

Table 4-42. Emissions reductions for the oil and gas sectors due to applying the Oil and Gas NSPS	177

Table 4-43. SCCs in np_oilgas for which the Oil and Gas NSPS controls were applied	177

Table 4-44. SCCs in pt_oilgas for which the Oil and Gas NSPS controls were applied	178

Table 4-45. Emissions reductions in nonpt due to RICE NSPS	182

Table 4-46. Emissions reductions in ptnonipm due to the RICE NSPS	182

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Table 4-47. Emissions reductions in np_oilgas due to the RICE NSPS	182

Table 4-48. Emissions reductions in pt_oilgas du to the RICE NSPS	182

Table 4-49. SCCs and Engine Types where RICE NSPS controls applied for nonpt and ptnonipm	182

Table 4-50. Non-point Oil and Gas SCCs where RICE NSPS controls are applied	183

Table 4-51. Point source SCCs in ptoilgas sector where RICE NSPS controls applied	184

Table 4-52. Summary of fuel sulfur rule impacts on nonpoint S02 emissions for 2032	184

Table 4-53. Stationary gas turbines NSPS analysis and resulting emission rates used to compute controls. 185

Table 4-54. Emissions reductions due to the Natural Gas Turbines NSPS	186

Table 4-55. SCCs in ptnonipm for which Natural Gas Turbines NSPS controls were applied	186

Table 4-56. SCCs in pt_oilgas for which Natural Gas Turbines NSPS controls were applied	187

Table 4-57. Process Heaters NSPS analysis and 2018v2 new emission rates used to estimate controls	187

Table 4-58. Emissions reductions due to the application of the Process Heaters NSPS	188

Table 4-59. SCCs in ptnonipm for which Process Heaters NSPS controls were applied	188

Table 4-60. SCCs in pt oilgas for which Process Heaters NSPS controls were applied	189

Table 4-61. NOx emissions reductions after application of Good Neighbor Plan control packet	190

Table 4-62. Light duty greenhouse gas rule adjustments for 2032 onroad emissions	192

Table 4-63. Factors used to Project VMT to analytic years	193

Table 5-1. National by-sector CAP emissions for the 2018gg case, 12US1 grid (tons/yr)	199

Table 5-2. National by-sector CAP emissions for the 2032gg2 case, 12US1 grid (tons/yr)	200

Table 5-3. National by-sector CAP emissions for the 2018gg case, 36US3 grid (tons/yr)	201

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List of Figures

Figure 2-1. Impact of adjustments to fugitive dust emissions due to transport fraction and precipitation	33

Figure 2-2. "Bidi" modeling system used to compute fertilizer application emissions	36

Figure 2-3. Map of Representative Counties	48

Figure 2-4. 2017NEI geographical extent of marine emissions (solid) and the U.S. ECA (dashed)	53

Figure 2-5. 2017 US Railroad Traffic Density in Millions of Gross Tons per Route Mile (MGT)	60

Figure 2-6. Class I Railroads in the United States	61

Figure 2-7. Class II and III Railroads in the United States	62

Figure 2-8. Amtrak Routes with Diesel-powered Passenger Trains	63

Figure 2-9. Processing flow for fire emission estimates	70

Figure 2-10. Default fire type assignment by state and month where data are only from satellites	70

Figure 2-11. Blue Sky Pipeline	71

Figure 3-1. Air quality modeling domains	81

Figure 3-2. Process of integrating NBAFM with VOC for use in VOC Speciation	86

Figure 3-3. Eliminating unmeasured spikes in CEMS data	104

Figure 3-4. Temporal Profile Input Unit Counts by Fuel and Peaking Unit Classification	105

Figure 3-5. Example Daily Temporal Profiles for the LADCO Region and the Gas Fuel Type	106

Figure 3-6. Example Diurnal Temporal Profiles for the MANE-VU Region and the Coal Fuel Type	107

Figure 3-7. Non-CEMS EGU Temporal Profile Aggregation Regions	108

Figure 3-8. Analytic Year Emissions Follow the Pattern of Base Year Emissions	Ill

Figure 3-9. Excess Emissions Apportioned to Hours Less than the Historic Maximum	Ill

Figure 3-10. Regional Profile Applied due to not being able to Adjust below Historic Maximum	112

Figure 3-11. Regional Profile Applied, but Exceeds Historic Maximum in Some Hours	112

Figure 3-12. Diurnal Profile for all Airport SCCs	113

Figure 3-13. Weekly profile for all Airport SCCs	113

Figure 3-14. Monthly Profile for all Airport SCCs	114

Figure 3-15. Alaska Seaplane Profile	114

Figure 3-16. Example of RWC temporal allocation using a 50 versus 60 °F threshold	115

Figure 3-17. RWC diurnal temporal profile	116

Figure 3-18. Data used to produce a diurnal profile for OHH, based on heat load (BTU/hr)	117

Figure 3-19. Day-of-week temporal profiles for OHH and Recreational RWC	117

Figure 3-20. Annual-to-month temporal profiles for OHH and recreational RWC	118

Figure 3-21. Example of animal NH3 emissions temporal allocation approach (daily total emissions)	119

Figure 3-22. Example of temporal variability of NOx emissions	120

Figure 3-23. Sample onroad diurnal profiles for Fulton County, GA	121

Figure 3-24. Methods to Populate Onroad Speeds and Temporal Profiles by Road Type	122

Figure 3-25. Regions for computing Region Average Speeds and Temporal Profiles	124

Figure 3-26. Example of Temporal Profiles for Combination Trucks	125

Figure 3-27. Example Nonroad Day-of-week Temporal Profiles	126

Figure 3-28. Example Nonroad Diurnal Temporal Profiles	126

Figure 3-29. Agricultural burning diurnal temporal profile	128

Figure 3-30. Prescribed and Wildfire diurnal temporal profiles	128

Figure 4-1. EIA Oil and Gas Supply Regions as of AEO2022	167

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Acronyms

AADT	Annual average daily traffic

AE6	CMAQ Aerosol Module, version 6, introduced in CMAQ v5.0

AEO	Annual Energy Outlook

AERMOD	American Meteorological Society/Environmental Protection Agency Regulatory
Model

AIS	Automated Identification System

APU	Auxiliary power unit

BEIS	Biogenic Emissions Inventory System

BELD	Biogenic Emissions Land use Database

BenMAP	Benefits Mapping and Analysis Program

BPS	Bulk Plant Storage

BTP	Bulk Terminal (Plant) to Pump

C1C2	Category 1 and 2 commercial marine vessels

C3	Category 3 (commercial marine vessels)

CAMD	EPA's Clean Air Markets Division

CAMx	Comprehensive Air Quality Model with Extensions

CAP	Criteria Air Pollutant

CARB	California Air Resources Board

CB05	Carbon Bond 2005 chemical mechanism

CB6	Version 6 of the Carbon Bond mechanism

CBM	Coal-bed methane

CDB	County database (input to MOVES model)

CEMS	Continuous Emissions Monitoring System

CISWI	Commercial and Industrial Solid Waste Incinerators

CMAQ	Community Multiscale Air Quality

CMV	Commercial Marine Vessel

CNG	Compressed natural gas

CO	Carbon monoxide

CONUS	Continental United States

Co ST	Control Strategy Tool

CRC	Coordinating Research Council

CSAPR	Cross-State Air Pollution Rule

E0, E10, E85	0%, 10% and 85% Ethanol blend gasoline, respectively

ECA	Emissions Control Area

ECCC	Environment and Climate Change Canada

EF	Emission Factor

EGU	Electric Generating Units

EIA	Energy Information Administration

EIS	Emissions Inventory System

EPA	Environmental Protection Agency

EMFAC	EMission FACtor (California's onroad mobile model)

EPIC	Environmental Policy Integrated Climate modeling system

FAA	Federal Aviation Administration

FCCS	Fuel Characteristic Classification System

FEST-C	Fertilizer Emission Scenario Tool for CMAQ

FF10	Flat File 2010

FINN	Fire Inventory from the National Center for Atmospheric Research

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FIPS

Federal Information Processing Standards

FHWA

Federal Highway Administration

HAP

Hazardous Air Pollutant

HMS

Hazard Mapping System

HPMS

Highway Performance Monitoring System

ICI

Industrial/Commercial/Institutional (boilers and process heaters)

I/M

Inspection and Maintenance

IMO

International Marine Organization

IPM

Integrated Planning Model

LADCO

Lake Michigan Air Directors Consortium

LDV

Light-Duty Vehicle

LPG

Liquified Petroleum Gas

MACT

Maximum Achievable Control Technology

MARAMA

Mid-Atlantic Regional Air Management Association

MATS

Mercury and Air Toxics Standards

MCIP

Meteorology-Chemistry Interface Processor

MMS

Minerals Management Service (now known as the Bureau of Energy Management,



Regulation and Enforcement (BOEMRE)

MOVES

Motor Vehicle Emissions Simulator

MSA

Metropolitan Statistical Area

MTBE

Methyl tert-butyl ether

MWC

Municipal waste combustor

MY

Model year

NAAQS

National Ambient Air Quality Standards

NAICS

North American Industry Classification System

NBAFM

Naphthalene, Benzene, Acetaldehyde, Formaldehyde and Methanol

NCAR

National Center for Atmospheric Research

NEEDS

National Electric Energy Database System

NEI

National Emission Inventory

NESCAUM

Northeast States for Coordinated Air Use Management

NH3

Ammonia

NLCD

National Land Cover Database

NO A A

National Oceanic and Atmospheric Administration

NONROAD

OTAQ's model for estimation of nonroad mobile emissions

NOx

Nitrogen oxides

NSPS

New Source Performance Standards

OHH

Outdoor Hydronic Heater

ONI

Off network idling

OTAQ

EPA's Office of Transportation and Air Quality

ORIS

Office of Regulatory Information System

ORD

EPA's Office of Research and Development

OSAT

Ozone Source Apportionment Technology

PFC

Portable Fuel Container

PM2.5

Particulate matter less than or equal to 2.5 microns

PM10

Particulate matter less than or equal to 10 microns

PPm

Parts per million

ppmv

Parts per million by volume

PSAT

Particulate Matter Source Apportionment Technology

RACT

Reasonably Available Control Technology

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RBT

Refinery to Bulk Terminal

RIA

Regulatory Impact Analysis

RICE

Reciprocating Internal Combustion Engine

RWC

Residential Wood Combustion

RPD

Rate-per-vehicle (emission mode used in SMOKE-MOVES)

RPH

Rate-per-hour for hoteling (emission mode used in SMOKE-MOVES)

RPHO

Rate-per-hour for off-network idling (emission mode used in SMOKE-



MOVES)

RPP

Rate-per-profile (emission mode used in SMOKE-MOVES)

RPS

Rate-per-start (emission mode used in SMOKE-MOVES)

RPV

Rate-per-vehicle (emission mode used in SMOKE-MOVES)

RVP

Reid Vapor Pressure

see

Source Classification Code

SMARTFIRE2

Satellite Mapping Automated Reanalysis Tool for Fire Incident Reconciliation



version 2

SMOKE

Sparse Matrix Operator Kernel Emissions

SOi

Sulfur dioxide

SOA

Secondary Organic Aerosol

SIP

State Implementation Plan

SPDPRO

Hourly Speed Profiles for weekday versus weekend

S/L/T

state, local, and tribal

TAF

Terminal Area Forecast

TCEQ

Texas Commission on Environmental Quality

TOG

Total Organic Gas

TSD

Technical support document

USD A

United States Department of Agriculture

VIIRS

Visible Infrared Imaging Radiometer Suite

VOC

Volatile organic compounds

VMT

Vehicle miles traveled

VPOP

Vehicle Population

WRAP

Western Regional Air Partnership

WRF

Weather Research and Forecasting Model

2014NEIv2

2014 National Emissions Inventory (NEI), version 2

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1 Introduction

The U.S. Environmental Protection Agency (EPA), has created a 2018 version 2 platform for use in air
quality modeling analyses. This platform primarily draws on data from the 2017 National Emissions
Inventory (NEI) (EPA, 2021b), although the emissions were updated to represent the year 2018 through
the incorporation of 2018-specific data along with adjustment methods appropriate for each sector. The
analytic year inventories were developed starting with the base year 2018 inventory using sector-specific
methods as described below. This 2018 platform supports applications related to particulate matter (PM).
An earlier version of a 2018 platform was developed in 2021 in support of ozone, PM and air toxics air
quality modeling analyses (EPA, 2022a).

The full air quality modeling platform consists of all the emissions inventories and ancillary data files
used for emissions modeling, as well as the meteorological, initial condition, and boundary condition files
needed to run the air quality model. This document focuses on the emissions modeling data and
techniques that comprise the emission modeling platform including the emission inventories, the ancillary
data files, and the approaches used to transform inventories for use in air quality modeling.

This emissions modeling platform includes all criteria air pollutants (CAPs) and precursors, and a group
of hazardous air pollutants (HAPs). The group of HAPs are those explicitly used by the chemical
mechanism in the Community Multiscale Air Quality (CMAQ) model (Appel et al., 2018) for
ozone/particulate matter (PM): chlorine (CI), hydrogen chloride (HC1), benzene, acetaldehyde,
formaldehyde, methanol, naphthalene. The modeling domain includes the lower 48 states and parts of
Canada and Mexico. The modeling cases for this platform were developed for studies with both the
CMAQ model and with the Comprehensive Air Quality Model with Extensions (CAMx). The emissions
modeling process used first prepares outputs in the format used by CMAQ, after which those emissions
data are converted to the formats needed by CAMx.

The 2018 platform consists of cases that represent the years 2018 and 2032 with the abbreviations
2018gg_18j and 2032gg2_18j, respectively. Derivatives of these cases that included source
apportionment by state were also developed. This platform accounts for atmospheric chemistry and
transport within a state-of-the-art photochemical grid model. In the case abbreviation 2018gg_18j, 2018 is
the year represented by the emissions; the "g" represents the base year emissions modeling platform
iteration, which here shows that g is for the 2018 platform which started with the 2017 NEI; and the "g"
stands for the seventh configuration of emissions modeled for that modeling platform. In the script and
data directories this platform is known as "em_v8.1." Data and summary reports for this platform are
available from https://www.epa.gov/air-emissions-modeling/2018v2-emissions-modeling-platform. It is
distinguished from the original 2018 platform used for 2018 AirToxScreen that is called "em_v8." Note
that the original 2018 platform did not include analytic year emissions.

The gridded meteorological model used to provide input data for the emissions modeling was developed
using the Weather Research and Forecasting Model (WRF,

https://ral.ucar.edu/solutions/products/weather-research-and-forecasting-model-wrf) version 3.8,
Advanced Research WRF core (Skamarock, et al., 2008). The WRF Model is a mesoscale numerical
weather prediction system developed for both operational forecasting and atmospheric research
applications. The WRF was run for 2018 over a domain covering the continental U.S. at a 12km
resolution with 35 vertical layers. The run for this platform included high resolution sea surface
temperature data from the Group for High Resolution Sea Surface Temperature (GHRSST) (see

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https://www.ghrsst.org/) and is given the EPA meteorological case label "18j." The full case abbreviation
includes this suffix following the emissions portion of the case name to fully specify the abbreviation of
the base year case as "2018gf_18j."

The emissions modeling platform includes point sources, nonpoint sources, commercial marine vessels
(CMV), onroad and nonroad mobile sources, and fires for the U.S., Canada, and Mexico. Some platform
categories use more disaggregated data than are made available in the NEI. For example, in the platform,
onroad mobile source emissions are represented as hourly emissions by vehicle type, fuel type process
and road type while the NEI emissions are aggregated to vehicle type/fuel type totals and annual temporal
resolution. A full NEI was not developed for the year 2018 because only point sources above a certain
potential to emit must be submitted for years between the full triennial NEI years (e.g., 2014, 2017, 2020).
Emissions from Canada and Mexico are used for the modeling platform but are not part of the NEI.

The primary emissions modeling tool used to create the air quality model-ready emissions was the Sparse
Matrix Operator Kernel Emissions (SMOKE) modeling system (http://www.smoke-model.org/), version
4.8.1 (SMOKE 4.8.1). Emissions files were created for a 36-km national grid and for a 12-km national
grid, both of which include the contiguous states and parts of Canada and Mexico as shown in Figure 3-1.
Emissions at 36-km were only created for the inventory year 2018.

This document contains six sections. Section 2 describes the base year inventories input to SMOKE.
Section 3 describes the emissions modeling and the ancillary files used to process the emission
inventories into air quality model-ready inputs. Methods to develop analytic year emissions are described
in Section 4. Data summaries are provided in Section 5. Section 6 provides references. Note that all tables
of emissions totals in this document are in the units of short tons/year.

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2 Base Year Emissions Inventories and Approaches

This section summarizes the emissions data that make up the 2018 base year emissions and provides
details about the data contained in each of the platform sectors. The original starting point for the
emission inventories was the original 2018 platform, which incorporated data and methods from the 2017
NEI. The base year emissions for many of the sectors in this platform are consistent with original
platform, which had a case abbreviation of 2018gc.

Data and documentation for the 2017NEI, including a TSD, are available from https://www.epa.gov/air-
emissions-inventories/2017-national-emissions-inventory-nei-data (EPA, 2021b). In addition to U.S.
emissions from the NEI data categories of point, nonpoint, onroad, nonroad, and events (i.e., fires),
emissions from the Canadian and Mexican inventories are included in the 2018v2 platform. The Canadian
and Mexican inventories in the 2018v2 platform were not changed from those in the 2016v2 platform
(EPA, 2022b), although they were reprocessed for the year 2018. The Canadian inventories were provided
by Environment and Climate Change Canada (ECCC), and most of the inventories for Mexico are based
on data provided by SEMARNAT.

The triennial year NEI data for CAPs are largely compiled from data submitted by state, local and tribal
(S/L/T) air agencies. A large proportion of HAP emissions data in the NEI are also from the S/L/T
agencies, but, are augmented by the EPA when not available from S/L/Ts. The EPA uses the Emissions
Inventory System (EIS) to compile the NEI. EIS includes hundreds of automated quality assurance checks
to help improve data quality, and also supports tracking release point (e.g., stack) coordinates separately
from facility coordinates. The EPA collaborates extensively with S/L/T agencies to ensure a high quality
of data in the NEI. Because 2018 is not a triennial NEI year, the inventories for most emissions modeling
sectors were modified in some way to represent the year 2018 to the extent possible.

For interim years other than triennial NEI years, point source data are typically pulled forward from the
most recent triennial NEI year for the sources that were not reported by S/L/Ts for the interim year. Thus,
the 2018 point source emission inventories for the platform include emissions primarily from S/L/T-
submitted data. Agricultural and wildland fire emissions represent the year 2018 and are consistent with
those in 2018gc. In 2018gg, most anthropogenic emissions are consistent with those in 2018gc, although
some had minor adjustments as described in Table 2-1. Onroad and nonroad mobile source emissions
were developed using the Motor Vehicle Emission Simulator (MOVES). Onroad emissions were
developed based on emissions factors output from MOVES3 for the year 2018. Nonroad emissions were
consistent with those in 2018gc and were generated using MOVES3, including the spatial allocation
factors made for the 2016vl platform.

For the purposes of preparing the air quality model-ready emissions, emissions from the five NEI data
categories (i.e., point, nonpoint, onroad, nonroad, and events) are split into finer-grained sectors used for
emissions modeling. The significance of an emissions modeling or "platform sector" is that the data are
run through the SMOKE programs independently from the other sectors except for the final merge. The
final merge program (Mrggrid) combines the sector-specific gridded, speciated, hourly emissions together
to create CMAQ-ready emission inputs.

The emission inventories in SMOKE input formats for the platform are available from EPA's Air
Emissions Modeling website: https://www.epa.gov/air-emissions-modeling/2018v2-platform , The
platform informational text file describes the particular zipped files associated with each platform sector
and provides notes about how SMOKE should be run for each sector. Summary reports are available in

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addition to the data files for the 2018v2 platform. The types of reports include state summaries of
inventory pollutants and model species by modeling platform sector and county totals by modeling
platform sector.

Table 2-1 presents an overview of how base year emission for the sectors in the emissions modeling
platform were developed and how they relate to the NEI as their starting point. The platform sector
abbreviations are provided in italics. These abbreviations are used in the SMOKE modeling scripts,
inventory file names, and throughout the remainder of this document. Additional details on the changes
made in the 2018v2 platform for each sector are available in the sector-specific subsections that follow.

Other natural emissions are also merged in with the sectors in Table 2-1: ocean chlorine and sea salt, and
lightning NOx. The ocean chlorine gas emission estimates are based on the build-up of molecular chlorine
(Cb) concentrations in oceanic air masses (Bullock and Brehme, 2002). In CMAQ, the species name is
"CL2." For more information on the natural emissions, see Section 2.7.7.

Table 2-1. Platform sectors for the 2018gg emissions modeling case

Platform Sector:

abbreviation

NEI Data
Category

Description and resolution of the data input to SMOKE

EGU units:

ptegu

Point

Point source electric generating units (EGUs) for 2018 from the Emissions
Inventory System (EIS) based on the winter 2022 point flat file as was used
for 2018 AirToxScreen. The inventory emissions are replaced with hourly
2018 Continuous Emissions Monitoring System (CEMS) values for nitrogen
oxides (NOx) and sulfur dioxide (S02)for any units that are matched to the
NEI, and other pollutants for matched units are scaled from the 2018 point
inventory using CEMS heat input. Emissions for all sources not matched to
CEMS data come from the annual inventory. Annual resolution for sources
not matched to CEMS data, hourly for CEMS sources. EGUs closed in 2018
are not part of the inventory.

Point source oil and
gas:

ptoilgas

Point

Point sources for 2018 including S/L/T data for oil and gas production and
related processes for facilities with North American Industry Classification
System (NAICS) codes related to Oil and Gas Extraction, Natural Gas
Distribution, Drilling Oil and Gas Wells, Support Activities for Oil and Gas
Operations, Pipeline Transportation of Crude Oil, and Pipeline Transportation
of Natural Gas. Includes U.S. offshore oil production from the 2017NEI
Production-related sources without 2018 data were pulled forward from 2017
NEI and adjusted to 2018. In NM and UT, the WRAP inventory from the
2016v3 platform (EPA, 2023a) was used. Annual resolution.

Aircraft and
ground support
equipment: airports

Point

2017 NEI point source emissions from aircraft up to 3,000 ft elevation and
emissions from ground support equipment, adjusted to 2018 using Terminal
Area Forecast (TAF) data. Airport-specific factors were used where available,
state average factors were used for regional airports, and no change was made
to military aircraft from 2017. Annual resolution.

Remaining non-
EGU point:

ptnonipm

Point

All 2018 point source inventory records not matched to the ptegu, airports, or
pt_oilgas sectors, including updates submitted by state and local agencies
including some sources that were not operating in 2018 but did operate in
later years use the winter 2022 inventory as was used for 2018 AirToxScreen.
Closures were reviewed and implemented based on the most recent
submissions to the Emissions Inventory System (EIS). Includes 2017 NEI rail
yard emissions, adjusted to 2018 using same projection factors as the rail
sector. Annual resolution.

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Platform Sector:

abbreviation

NEI Data
Category

Description and resolution of the data input to SMOKE

Agricultural
fertilizer:

fertilizer

Nonpoint

Nonpoint agricultural fertilizer application emissions of ammonia computed
inline within CMAQ for 2018 through the bidirectional ammonia flux
process. Created an emissions inventory post-CMAQ to use for data
summaries but did not run SMOKE. Ran inline, but used county and monthly
resolution for the output inventory.

Agricultural
Livestock:

livestock

Nonpoint

2017 NEI nonpoint agricultural livestock emissions including ammonia and
other pollutants (except PM2 5). Same as 2018gc except included a correction
for Maryland. County and annual resolution.

Agricultural fires
with point
resolution: ptagfire

Nonpoint

2018 agricultural fire sources based on EPA-developed data, represented as
point source day-specific emissions. Same as 2018gc. They are in the NEI
nonpoint data category, but in the platform, they are treated as point sources.
Day-specific resolution.

Area fugitive dust:

afdust

Nonpoint

PM10 and PM2 5 fugitive dust sources based on the 2017 NEI nonpoint
inventory, including building construction, road construction, agricultural
dust, and paved and unpaved road dust; with paved road dust adjusted to 2018
based on vehicle miles traveled (VMT). Emissions are reduced during
modeling according to a transport fraction and a 2018 meteorology-based
(precipitation and snow/ice cover) zero-out. Afdust emissions from the
portion of southeast Alaska inside the 36US3 domain are processed in a
separate sector called 'afdust ak'. County and annual resolution.

Biogenic:

beis

Nonpoint

Year 2018, hour-specific, grid cell-specific emissions generated from a new
B3GRD files for 12US1 and 36US3 based on a corrected version of the
BEIS3.7 model within SMOKE, including emissions in Canada and Mexico
using BELD5 land use data. Gridded and hourly resolution.

Category 1, 2 CMV:

cmv_clc2

Nonpoint

2017 NEI Category 1 and category 2 (C1C2) commercial marine vessel
(CMV) emissions based on Automatic Identification System (AIS) data,
adjusted to 2018, including the county apportionment fix consistent with what
was done for 2016v3. Same as 2018gc. Includes C1C2 CMV emissions in
U.S. state and Federal waters along with non-U.S. C1C2 emissions within the
modeling domains. Gridded and hourly resolution.

Category 3 CMV:

cmv_c3

Nonpoint

2017 NEI Category 3 (C3) CMV emissions converted to point sources based
on the center of the grid cells and adjusted to 2018, including the county
apportionment fix consistent with what was done for 2016v3. Includes C3
emissions in U.S. state and Federal waters, and also all non-U.S. C3
emissions within the modeling domains. Same as 2018gc. Gridded and hourly
resolution.

Locomotives :
rail

Nonpoint

2017 NEI line haul rail locomotives emissions adjusted to 2018. Includes
freight and commuter rail emissions. Same as 2018gc. County and annual
resolution.

Solvents :

npsolvents

Nonpoint
(some
Point)

VOC emissions from solvents for the year 2018 derived using the January
2022 version of the VCPy framework (Seltzer et al., 2021). Includes
household cleaners, personal care products, adhesives, architectural coatings,
aerosol coatings, industrial coatings, allied paint products, printing inks, dry-
cleaning emissions, and agricultural pesticides. County and annual resolution.

Nonpoint source oil
and gas:
npoilgas

Nonpoint

2018 nonpoint oil and gas emissions output from the oil and gas tool using
2018 activity data. For exploration the 2018 oil and gas tool output were used
directly. For production used the WRAP inventory from the 2016v3 platform
in New Mexico and North Dakota; the 2017 NEI in California, Colorado,
Oklahoma, Texas, Utah, and Wyoming; and oil and gas tool outputs for 2018
in all other states. County and annual resolution

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Platform Sector:

abbreviation

NEI Data
Category

Description and resolution of the data input to SMOKE

Residential Wood
Combustion:

rwc

Nonpoint

2017 NEI nonpoint sources from residential wood combustion (RWC) with
no adjustments to 2018. Same as 2018gc. County and annual resolution.

Remaining
nonpoint:

nonpt

Nonpoint

2017 NEI nonpoint sources that are not included in other platform sectors
with no adjustments to 2018. Same as 2018gc. For 2018 used 2017 NEI for
all sources. County and annual resolution.

Nonroad:

nonroad

Nonroad

2018 nonroad equipment emissions developed with MOVES3, including the
updates made to spatial apportionment that were developed for the 2016vl
platform. MOVES3 was used for all states except California and Texas.
California submitted emissions for 2017 and 2023 which were interpolated to
2018; Texas submitted emissions for 2017 and 2020, which were interpolated
to 2018. Same as 2018gc. County and monthly resolution.

Onroad:

onroad

Onroad

2018 onroad mobile source gasoline and diesel vehicles from moving and
non-moving vehicles that drive on roads, along with vehicle refueling.
Includes the following modes: exhaust, extended idle, auxiliary power units,
off network idling, starts, evaporative, permeation, refueling, and brake and
tire wear. For all states except California, developed using SMOKE-MOVES
with emission factor tables produced by MOVES3. Activity data were
projected to 2018 using factors derived from data obtained from Federal
Highway Administration and state departments of transportation. Same as
2018gc. County and hourly resolution.

Onroad California:

onroadcaadj

Onroad

California-provided CAP onroad mobile source gasoline and diesel vehicles
based on the EMFAC2017 model interpolated to 2018 between 2017 and
2023. The 2018 data were gridded and temporalized using MOVES3 outputs.
Volatile organic compound (VOC) HAP emissions derived from California-
provided VOC emissions and MOVES-based speciation. Same as 2018gc.
County and hourly resolution.

Point source fires-

ptfire-rx
ptfire-wild

Events

Point source day-specific wildfires and prescribed fires for 2018 computed
using Satellite Mapping Automated Reanalysis Tool for Fire Incident
Reconciliation version 2 (SMARTFIRE2) and BlueSky Pipeline for both
flaming and smoldering processes (i.e., SCCs 281XXXX002). The ptfire-rx
sectors includes Flint Hills grasslands fires; wildfires were run in a separate
sector ptfire-wild. Smoldering emissions forced into layer 1 (by adjusting
heat flux). Same as 2018gc. Daily resolution.

Non-US. Fires:
ptfireothna

N/A

Point source day-specific wildfires and agricultural fires outside of the U.S.
for 2018 from v 1.5 of the Fire INventory (FINN) from National Center for
Atmospheric Research (NCAR, 2017 and Wiedinmyer, C., 2011) for Canada,
Mexico, Caribbean, Central American, and other international fires. Includes
any prescribed fires although they are not distinguished from wildfires. Same
as 2018gc. Daily resolution.

Other Area Fugitive
dust sources not
from the NEI:

othafdust

N/A

Area fugitive dust sources of particulate matter emissions excluding dust
from livestock land tilling from agricultural activities, from Environment and
Climate Change Canada (ECCC) for 2016. Transport fraction adjustments
applied along with a 2018-specific meteorology-based (precipitation and
snow/ice cover) zero-out. Same as 2018gc. County and annual resolution.

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Platform Sector:

abbreviation

NEI Data
Category

Description and resolution of the data input to SMOKE

Other Point
Fugitive dust
sources not from
the NEI:
othptdust

N/A

2016 point source fugitive dust sources of particulate matter emissions
including dust from livestock and land tilling from agricultural activities,
provided by ECCC. Wind erosion emissions were not included. Transport
fraction adjustments applied along with a 2018-specific meteorology-based
(precipitation and snow/ice cover) zero-out. Same as 2018gc. Monthly
resolution.

Other point sources
not from the NEI:
othpt

N/A

2016 point source emissions from the ECCC including Canadian sources
other than agricultural ammonia and low-level oil and gas sources, along with
emissions from Mexico's 2016 inventory projected to 2018. Canada same as
2018gc, Mexico updated from 2018gc. Monthly resolution for Canada airport
emissions, annual resolution for the remainder of Canada and all of Mexico.

Canada ag not from
the NEI:

Canada ag

N/A

2016 agricultural point sources from the ECCC, including agricultural
ammonia. Same as 2018gc, except with these emissions split out from the
othpt sector. Monthly resolution.

Canada oil and gas
2D not from the
NEI:

Canada og2D

N/A

2016 low-level point oil and gas sources with emissions forced into 2D low-
level to reduce the size of the othpt sector. Point oil and gas sources subject to
plume rise remain in the othpt sector. Same as 2018gc, except with these
emissions split out from the othpt sector. Annual resolution.

Other non-NEI
nonpoint and
nonroad:

othar

N/A

2016 Canada emissions from the ECCC inventory, with nonroad emissions
projected from 2016 to 2018 using US nonroad trends. Mexico (municipio
resolution) emissions projected from 2016 to 2018. Canada same as 2018gc,
Mexico updated from 2018gc. Resolution: Canada: province or sub-province
resolution; monthly for nonroad sources and annual for rail and other
nonpoint sectors; Mexico: municipio resolution; annual nonpoint and nonroad
mobile inventories.

Other non-NEI
onroad sources:

onroadcan

N/A

Year 2016 Canada from the ECCC onroad mobile inventory projected to
2018 using US onroad trends. Separate trends applied to refueling and non-
refueling. Same as 2018gc. Province resolution or sub-province resolution,
depending on the province; Monthly resolution.

Other non-NEI
onroad sources:

onroad mex

N/A

Year 2018 Mexico onroad mobile inventory from MOVES-Mexico. Same as
from 2018gc. Municipio and monthly resolution.

2.1 Point sources (ptegu, pt_oilgas, ptnonipm, airports)

Point sources are sources of emissions for which specific geographic coordinates (e.g., latitude/longitude)
are specified, as in the case of an individual facility. A facility may have multiple emission release points
that may be characterized as units such as boilers, reactors, spray booths, kilns, etc. A unit may have
multiple processes (e.g., a boiler that sometimes burns residual oil and sometimes burns natural gas). This
section describes NEI point sources within the contiguous U.S. and the offshore oil platforms which are
processed by SMOKE as point source inventories.

A full NEI is compiled every three years including 2014, 2017 and 2020. In the intervening years, year-
specific emissions for point sources that exceed the potential to emit threshold as defined in the Air
Emissions Reporting Requirements (AERR)1 must be submitted by the responsible state, local, or tribal

1 80 FR 8787 published 2/19/2015. See: https://www.federalregister.gov/documents/2015/02/19/2015-03470/revisions-to-the-
air-emissions-reporting-reauirements-revisions-to-lead-pb-reporting-threshold-and

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agencies. These emissions, and any relevant closures, are submitted to the Emissions Inventory System
(EIS) used to compile the NEI. Sources not updated by the responsible agencies for the interim year are
either carried forward from the most recent triennial NEI if they have not been marked as closed. While
point source emissions are available in EIS for the year 2018, a full set of documentation on how the 2018
point source inventory was compiled is not available. The methods for point source emissions estimation
for the year of 2018 are similar to those used for the 2017 NEI. A comprehensive description of how point
source emissions were characterized and estimated in the 2017 NEI is available in the 2017 NEI TSD
(EPA, 2021).

The point source file used for the modeling platform was exported from EIS into the Flat File 2010
(FF10) format that is compatible with SMOKE (see

https://www.cmascenter.Org/smoke/documentation/4.9/html/ch06s02s08.htmn. The export of point source
emissions specific to 2018, including stack parameters and locations from EIS, was done on March 22,
2022. The flat file was modified to remove sources without specific locations (i.e., their FIPS code ends in
777). Then the point source FF10 was divided into point source sectors used in the platform: the EGU
sector (ptegu), point source oil and gas extraction-related emissions (pt oilgas), airport emissions were
put into the airports sector, and the remaining non-EGU sources into the non-IPM (ptnonipm) sector. The
split was done at the unit level for ptegu and facility level for pt oilgas such that a facility may have units
and processes in both ptnonipm and ptegu, but units cannot be in both pt oilgas and any other point
sector.

The EGU emissions are split out from the other sources to facilitate the use of distinct SMOKE temporal
processing and analytic-year projection techniques where the Integrated Planning Model (IPM) is used to
project EGU emissions and other techniques are used to project non-EGU emissions. The oil and gas
sector emissions (pt oilgas) were processed separately for summary tracking purposes and distinct
analytic-year projection techniques from the remaining non-EGU emissions (ptnonipm).

In some cases, data about facility or unit closures are entered into EIS after the inventory modeling
inventory flat were reviewed and implemented based on the most recent submissions to EIS. Prior to
processing through SMOKE, submitted closures were reviewed and if closed sources were found in the
inventory, those were removed.

While reviewing recent point source inventories it was determined that data submitted by some agencies
used specific default values for certain stack parameters that are not necessarily appropriate to use for
those sources. Defaulted values were noticed in data submissions for the states of Illinois, Louisiana,
Michigan, Pennsylvania, Texas, Wisconsin, and others. Using these default values can impact modeling
results, especially in fine scale modeling. When the stack parameters were substantially different from
average values for that source type, the defaulted stack parameters were replaced with the value from the
SMOKE PSTK file for that source classification code (SCC). The agencies and default values that were
replaced are shown in Table 2-2. Comments for any impacted inventory records were appended in the
FF10 inventory files with comments of the form "stktemp replaced with ptsk default" so the updated
records could be identified. These updates impacted the ptnonipm and pt oilgas inventories.

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Table 2-2. Default stack parameter replacements

Agency
abbreviation

Stkdiam

Stkhgt

Stktemp

Stkvel

CODPHE

0.1 ft

1 ft

70 degF or 72 degF



PADEP

0.1 ft

1 ft

70 degF

0.1 ft/s or 1000
ft/s

LADEQ

0.3 ft



70 degF or 77 degF

0.1 ft/s

ILEPA

0.33 ft

33 ft or 35 ft

70 degF



TXCEQ

1 ft or 3 ft

40 ft

72 degF

0.1 ft/s

NVBAQ



32.8 ft

72 degF



WIDNR



20 ft



3.281 ft/s

MIDEQ





70 degF or 72 degF



MNPCA





70 degF



IADNR





68 degF or 70 degF



ORDEQ





72 degF



MSDEQ





72 degF



SCDEQ





72 degF

1 ft/s

NCDAQ





72 degF

0.2 ft/s

INDEM





0 degF

0 ft/s

NEDEQ





350 degF

1.6666 ft/s

KYDAQ







0 ft/s

WYDEQ







11.46 ft/s

The non-EGlJ stationary point source (ptnonipm) emissions were input to SMOKE as annual emissions.
The full description of how the NEI emissions were developed is provided in the NEI documentation - a
brief summary of their development follows:

a.	CAP and HAP data were provided by States, locals and tribes under the Air Emissions Reporting
Rule (AERR) [the reporting size threshold is larger for inventory years between the triennial inventory
years of 2011, 2014, 2017, ...].

b.	EPA corrected known issues and filled PM data gaps.

c.	EPA added HAP data from the Toxic Release Inventory (TRI) where corresponding data was not
already provided by states/locals.

d.	EPA stored and applied matches of the point source units to units with CEMS data and also for all
EGU units modeled by EPA's Integrated Planning Model (IPM).

e.	Data for airports and rail yards were incorporated.

f.	Off-shore platform data were added from the Bureau of Ocean Energy Management (BOEM).

The changes made to the NEI point sources prior to modeling with SMOKE are as follows:

• The tribal data, which do not use state/county Federal Information Processing Standards (FIPS)
codes in the NEI, but rather use the tribal code, were assigned a state/county FIPS code of 88XXX,

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where XXX is the 3-digit tribal code in the NEI This change was made because SMOKE requires
all sources to have a state/county FIPS code.

• Sources that did not have specific counties assigned (i.e., the county code ends in 777) were not
included in the modeling because it was only possible to know the state in which the sources
resided, but no more specific details related to the location of the sources were available.

Each of the point sectors is processed separately through SMOKE as described in the following
subsections.

The inventory pollutants processed through SMOKE for all point source sectors included carbon
monoxide (CO), oxides of nitrogen (NOx), volatile organic compounds (VOC), sulfur dioxide (SO2),
ammonia (NH3), particles less than 10 microns in diameter (PM10), and particles less than 2.5 microns in
diameter (PM2.5), and all of the hazardous air pollutants (HAPs) listed in Table 3-3. The pollutants
naphthalene, benzene, acetaldehyde, formaldehyde, and methanol (NBAFM) species are based on
speciation of VOCs. The resulting VOC in the modeling system may be higher or lower than the VOC
emissions in the NEI; they would only be the same if the HAP inventory and speciation profiles were
exactly consistent. For HAPs other than those in NBAFM, there is no concern for double-counting since
CMAQ handles these outside of the CB6 chemical mechanism.

The ptnonipm and ptoilgas sector emissions were provided to SMOKE as annual emissions. For those
ptegu sources with CEMS data that could be matched to the point inventory from EIS, hourly CEMS NOx
and SO2 emissions were used rather than the annual total NEI emissions. For all other pollutants at
matched units, the annual emissions were used as-is from the NEI, but were allocated to hourly values
using heat input from the CEMS data. For the sources in the ptegu sector not matched to CEMS data,
daily emissions were created using an approach described in Section 2.1.1. For non-CEMS units other
than municipal waste combustors and cogeneration units, region- and pollutant-specific diurnal profiles
were applied to create hourly emissions.

2.1.1 EGU sector (ptegu)

The ptegu sector contains emissions from EGUs in the 2018 NEI point inventory that could be matched to
units found in the National Electric Energy Data System (NEEDS) v6 database
(https://www.epa.gov/airmarkets/national-electric-energy-data-svstem-needs-v6 dated 2/14/2023).

NEEDS is used by the Integrated Planning Model (1PM) to develop future year EGU emissions. It was
necessary to put these EGlJs into a separate sector in the platform because EGlJs use different temporal
profiles than other sources in the point sector and it is useful to segregate these emissions from the rest of
the point sources to facilitate summaries of the data. Sources not matched to units found in NEEDS are
placed into the pt oilgas or ptnonipm sectors. For studies with future year cases, the sources in the ptegu
sector are fully replaced with the emissions output from IPM. It is therefore important that the matching
between the NEI and NEEDS database be as complete as possible because there can be double-counting
of emissions in future year modeling scenarios if emissions for units projected by IPM are not properly
matched to the units in the point source inventory

The matching of NEEDS to the NEI sources was prioritized according to the amount of the emissions
produced by the source. In the SMOKE point flat file, emission records for sources that have been
matched to the NEEDS database have a value filled into the IPM YN column based on the matches
stored within EIS. The 2018 NEI point inventory consists of data submitted by S/L/T agencies and EPA
to the EIS for Type A (i.e., large) point sources. Those EGU sources in the 2017 NEI inventory that were

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not submitted or updated for 2018 and not identified as retired were retained in 2018, but for 2018v2 the
emissions values were pulled from the 2017 NEI where possible.

When possible, units in the ptegu sector are matched to 2018 CEMS data from EPA's Clean Air Markets
Division (CAMD) via ORIS facility codes and boiler ID (see https://campd.epa.gov/). For the matched
units, SMOKE replaces the 2018 emissions of NOx and SO2 with the CEMS emissions, thereby ignoring
the annual values specified in the NEI annual FF10 flat file. For other pollutants at matched units, the
hourly CEMS heat input data are used to allocate the NEI annual emissions to hourly values. All stack
parameters, stack locations, and Source Classification Codes (SCC) for these sources come from the NEI
or updates provided by data submitters outside of EIS. Because these attributes are obtained from the NEI,
the chemical speciation of VOC and PM2.5 for the sources is selected based on the SCC or in some cases,
based on unit-specific data. If CEMS data exists for a unit, but the unit is not matched to the NEI, the
CEMS data for that unit are not used in the modeling platform. However, if the source exists in the NEI
and is not matched to a CEMS unit, the emissions from that source are still modeled using the annual
emission value in the NEI temporally allocated to hourly values. The EGU flat file inventory is split into a
flat file with CEMS matches and a flat file without CEMS matches to support analysis and temporal
allocation to hourly values.

In the SMOKE point FF10 file, emission records for point sources matched to CEMS data have values
filled into the ORIS FACILITY CODE and ORIS BOILER ID columns. The CEMS data in SMOKE-
ready format is available at https://gaftp.epa.gov/DMDnLoad/emissions/smoke/. Many smaller emitters in
the CEMS program are not identified with ORIS facility or boiler IDs that can be matched to the NEI due
to inconsistencies in the way a unit is defined between the NEI and CEMS datasets, or due to
uncertainties in source identification such as inconsistent plant names in the two data systems. Also, the
NEEDS database of units modeled by IPM includes many smaller emitting EGUs that do not have CEMS.
Therefore, there will be more units in the NEEDS database than have CEMS data. The temporal
allocation of EGU units matched to CEMS is based on the CEMS data, whereas regional profiles are used
for most of the remaining units. More details can be found in Section 3.3.2.

Some EIS units match to multiple CAMD units based on cross-reference information in the EIS alternate
identifier table. The multiple matches are used to take advantage of hourly CEMS data when a CAMD
unit specific entry is not available in the inventory. Where a multiple match is made, the EIS unit is split
and the ORIS facility and boiler IDs are replaced with the individual CAMD unit IDs. The split EIS unit
NOX and S02 emissions annual emissions are replaced with the sum of CEMS values for that respective
unit. All other pollutants are scaled from the EIS unit into the split CAMD unit using the fraction of
annual heat input from the CAMD unit as part of the entire EIS unit. The NEEDS ID in the "ipm_yn"
column of the flat file is updated with a "_M_" between the facility and boiler identifiers to signify that
the EIS unit had multiple CEMS matches. The inventory records with multiple matches had the EIS unit
identifiers appended with the ORIS boiler identifier to distinguish each CEMS record in SMOKE.

For sources not matched to CEMS data, except for municipal waste combustors (MWCs) waste-to-energy
and cogeneration units, daily emissions were computed from the NEI annual emissions using average
CEMS data profiles specific to fuel type, pollutant,2 and IPM region. To allocate emissions to each hour
of the day, diurnal profiles were created using average CEMS data for heat input specific to fuel type and
IPM region. See Section 3.3.2 for more details on the temporal allocation approach for ptegu sources.

2 The year to day profiles use NOx and SO2 CEMS for NOx and SO2, respectively. For all other pollutants, they use heat input
CEMS data.

24


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MWC and cogeneration units without CEMS data available were specified to use uniform temporal
allocation such that the emissions are allocated to constant levels for every hour of the year. These sources
do not use hourly CEMs, and instead use a temporal profile that allocates the same emissions for each
day, combined with a uniform hourly temporal profile applied by SMOKE.

2.1.2 Point source oil and gas sector (pt_oilgas)

The ptoilgas sector consists of point source oil and gas emissions in United States, primarily pipeline-
transportation and some upstream exploration and production. Sources in the pt oilgas sector consist of
sources which are not electricity generating units (EGUs) and which have a North American Industry
Classification System (NAICS) code corresponding to oil and gas exploration, production, pipeline-
transportation or distribution. The pt oilgas sector was separated from the ptnonipm sector by selecting
sources with specific NAICS codes shown in Table 2-3. The use of NAICS to separate out the point oil
and gas emissions forces all sources within a facility to be in this sector, as opposed to ptegu where
sources within a facility can be split between ptnonipm and ptegu sectors.

Table 2-3. Point source oil and gas sector NAICS Codes

NAICS

NAICS description

2111

Oil and Gas Extraction

211111

Crude Petroleum and Natural Gas Extraction

211112

Natural Gas Liquid Extraction

21112

Crude Petroleum Extraction

211120

Crude Petroleum Extraction

21113

Natural Gas Extraction

211130

Natural Gas Extraction

213111

Drilling Oil and Gas Wells

213112

Support Activities for Oil and Gas Operations

2212

Natural Gas Distribution

22121

Natural Gas Distribution

221210

Natural Gas Distribution



Oil and Gas Pipeline and Related Structures

237120

Construction

4861

Pipeline Transportation of Crude Oil

48611

Pipeline Transportation of Crude Oil

486110

Pipeline Transportation of Crude Oil

4862

Pipeline Transportation of Natural Gas

48621

Pipeline Transportation of Natural Gas

486210

Pipeline Transportation of Natural Gas

The starting point for most states in the 2018v2 emissions platform pt oilgas inventory was the 2018
point source NEI. The 2018 inventory includes data submitted by S/L/T agencies and EPA to the EIS for
Type A (i.e., large) point sources. For the federally-owned offshore point inventory of oil and gas
platforms, a 2017 inventory was used that was developed by the U.S. Department of the Interior, Bureau

25


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of Ocean and Energy Management, Regulation, and Enforcement (BOEM). For 2018, New Mexico and
Utah used the WRAP oil and gas inventory from 2016v3 platform.

The NEI year that the data was submitted for is indicated by the calc_year field in the FF10 inventory
files. Sources in the 2018NEI in which the calc_year is 2017 were projected to 2018. Each
state/SCC/NAICS combination in the inventory was classified as either an oil source, a natural gas source,
a combination of oil and gas, or designated as a "no growth" source. Growth factors were based on
historical state production data from the Energy Information Administration (EIA) and are listed in Table
2-4. These factors were applied to sources withNAICS = 2111,21111,211111, 211112, and 213111 and
with production-related SCC processes in the pt_oilgas sector. States listed with N/A as values do not
have oil and gas activity data from which projection factors could be developed and therefore were held
flat with no change from 2017 to 2018.

For pipeline transportation, national projection factors of 17% for oil and 12% for gas were applied. The
"no growth" sources include all offshore and tribal land emissions, and all emissions with a NAICS code
associated with distribution, transportation, or support activities. The historical production data for years
2017 and 2018 for oil and natural gas were taken from the following websites:

•	https://www.eia.gov/dnav/pet/pet crd crpdn adc mbbl a.htm (Crude production)

•	http://www.eia.gov/dnav/ng/ng sum lsum a epgO fgw mmcf a.htm (Natural gas production)

Table 2-5 shows the national emissions for ptoilgas following the projection to 2018; these numbers only
reflect the portion of the inventory projected from 2017 to 2018.

Table 2-4. 2017-to-2018 projection factors for pt oilgas sector

State

Natural Gas
growth

Oil growth

Combination gas/oil growth

Alabama

-7.0%

-13.8%

-10.4%

Alaska

0.1%

-3.2%

-1.5%

Arizona

-25.0%

-15.4%

-20.2%

Arkansas

-15.1%

-5.4%

-10.2%

California

-4.6%

-2.4%

-3.5%

Colorado

8.3%

25.6%

17.0%

Florida

3.7%

-4.4%

-0.3%

Idaho

-50.8%

-3.3%

-27.0%

Illinois

15.6%

1.3%

8.5%

Indiana

-14.5%

-5.3%

-9.9%

Kansas

-8.3%

-3.1%

-5.7%

Kentucky

-5.3%

-8.6%

-6.9%

Louisiana

32.2%

-8.0%

12.1%

Maryland

-59.4%

#N/A

-59.4%

Michigan

-7.1%

-1.6%

-4.4%

Mississippi

-7.5%

-4.7%

-6.1%

Missouri

0.0%

-17.2%

-8.6%

Montana

-4.8%

4.0%

-0.4%

Nebraska

-4.8%

-3.2%

-4.0%

Nevada

0.0%

-10.8%

-5.4%

New Mexico

16.5%

44.6%

30.5%

26


-------
State

Natural Gas
growth

Oil growth

Combination gas/oil growth

New York

-6.5%

20.1%

6.8%

North Dakota

25.0%

17.9%

21.4%

Ohio

34.2%

13.8%

24.0%

Oklahoma

14.4%

20.2%

17.3%

Oregon

-24.3%

#N/A

-24.3%

Pennsylvania

14.9%

-1.3%

6.8%

South Dakota

-6.1%

-2.4%

-4.2%

Tennessee

10.1%

-22.5%

-6.2%

Texas District 1

4.1%

8.0%

6.1%

Texas District 10

-5.2%

-0.8%

-3.0%

Texas District 2

9.7%

10.4%

10.1%

Texas District 3

10.8%

21.2%

16.0%

Texas District 4

-5.8%

0.8%

-2.5%

Texas District 5

-6.9%

-5.8%

-6.3%

Texas District 6

19.1%

-2.2%

8.4%

Texas District 7B

-4.8%

-4.7%

-4.8%

Texas District 7C

15.4%

15.0%

15.2%

Texas District 8

45.9%

51.3%

48.6%

Texas District 8A

5.5%

2.9%

4.2%

Texas District 9

-7.5%

-5.7%

-6.6%

Utah

-6.1%

7.8%

0.8%

Virginia

-3.4%

-28.6%

-16.0%

West Virginia

17.0%

34.7%

25.8%

Wyoming

0.3%

16.2%

8.2%

Table 2-5. 2017 NEI-based sources in ptoilgas (excluding offshore) before and after projections to

2018

Pollutant

Before
projections

After projections

% change 2017 to 2018

CO

67,208

73,687

+9.6%

NH3

259.3

258.7

-0.3%

NOX

104,804

114,595

+9.3%

PM10-PRI

4,730

5,028

+6.3%

PM25-PRI

4,441

4,737

+6.7%

S02

2,725

2,847

+4.5%

VOC

64,152

71,193

+11.0%

2.1.3 Non-IPM sector (ptnonipm)

With minor exceptions, the ptnonipm sector contains point sources that are not in the airport, ptegu or
pt oilgas sectors. For the most part, the ptnonipm sector reflects the non-EGU sources of the NEI point
inventory; however, it is likely that some small low-emitting EGUs not matched to the NEEDS database
or to CEMS data are present in the ptnonipm sector. The ptnonipm emissions in the 2018v2 platform have
been updated from the 2018gc inventory by using a March 22, 2022 export from EIS.

27


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The ptnonipm sector contains a small amount of fugitive dust PM emissions from vehicular traffic on
paved or unpaved roads at industrial facilities, coal handling at coal mines, and grain elevators. Sources
with state/county FIPS code ending with "777" are in the NEI but are not included in any modeling
sectors. These sources typically represent mobile (temporary) asphalt plants that are only reported for
some states and are generally in a fixed location for only a part of the year and are therefore difficult to
allocate to specific places and days as is needed for modeling. Therefore, these sources are dropped from
the point-based sectors in the modeling platform.

For 2018v2, A review of stack parameters (i.e., height, diameter, velocity, temperature) was performed to
look for default values submitted for many stacks for the same type of source in the inventory. When
these parameters were substantially different from average values for that source type, the defaulted stack
parameters were replaced with the value from the SMOKE PSTK file for that SCC as shown in Table 2-2.

Emissions from rail yards are included in the ptnonipm sector. Railyards were projected to 2018 from the
2017 NEI railyard inventory using factors derived from the Annual Energy Outlook 2018
(http s: //www, ei a. gov/outl ooks/archive/aeo 18/).

2.1.4 Aircraft and ground support equipment (airports)

Emissions at airports were separated from other sources in the point inventory based on sources that have
the facility source type of 100 (airports). The airports sector includes all aircraft types used for public,
private, and military purposes and aircraft ground support equipment. The Federal Aviation
Administration's (FAA) Aviation Environmental Design Tool (AEDT) is used to estimate emissions for
this sector. For 2017, Texas and California submitted aircraft emissions. Additional information about
aircraft emission estimates can be found in section 3.2.2 of the 2017 NEI TSD. Terminal Area Forecast
(TAF) data were used to project 2017 NEI emissions to 2018. EPA used airport-specific factors where
available. Regional airports were projected using state average factors. Military airports were unchanged
from 2017. An update for the 2018 platform was that airport emissions were spread out into multiple
12km grid cells when the airport runways were determined to overlap multiple grid cells. Otherwise,
airport emissions for a specific airport are confined to one air quality model grid cell. The SCCs included
in the airport sector are shown in Table 2-6.

Table 2-6. SCCs for the airports sector

SCC

Tier 1
description

Tier 2 description

Hit 3 description

Tier 4 description

2265008005

Mobile
Sources

Off-highway
Vehicle Gasoline,
4-stroke

Airport Ground
Support Equipment

Airport Ground Support
Equipment

2267008005

Mobile
Sources

LPG

Airport Ground
Support Equipment

Airport Ground Support
Equipment

2275001000

Mobile
Sources

Aircraft

Military Aircraft

Total

2275020000

Mobile
Sources

Aircraft

Commercial Aircraft

Total: All Types

2275050011

Mobile
Sources

Aircraft

General Aviation

Piston

2275050012

Mobile
Sources

Aircraft

General Aviation

Turbine

28


-------
sec

Tier 1
description

Tier 2 description

Tier 3 description

Tier 4 description

2275060011

Mobile
Sources

Aircraft

Air Taxi

Piston

2275060012

Mobile
Sources

Aircraft

Air Taxi

Turbine

2275070000

Mobile
Sources

Aircraft

Aircraft Auxiliary
Power Units

Total

2.2 Nonpoint sources (afdust, fertilizer, livestock, np oilgas,
npsoivents, rwc, nonpt)

This section describes the stationary nonpoint sources in the NEI nonpoint data category. Locomotives,
CI and C2 CMV, and C3 CMV are included in the NEI nonpoint data category, but are mobile sources
that are described in Section 2.4.

Nonpoint tribal emissions submitted to the NEI are dropped during spatial processing with SMOKE due
to the configuration of the spatial surrogates. Part of the reason for this is to prevent possible double-
counting with county-level emissions and also because spatial surrogates for tribal data are not currently
available. These omissions are not expected to have an impact on the results of the air quality modeling at
the 12-km resolution used for this platform.

The following subsections describe how the sources in the NEI nonpoint inventory were separated into
modeling platform sectors, along with any data that were updated replaced with non-NEI data.

2.2.1 Area fugitive dust (afdust)

The area-source fugitive dust (afdust) sector contains PMio and PM2.5 emission estimates for nonpoint
SCCs identified by EPA as dust sources. Categories included in the afdust sector are paved roads,
unpaved roads and airstrips, construction (residential, industrial, road and total), agriculture production,
and mining and quarrying. It does not include fugitive dust from grain elevators, coal handling at coal
mines, or vehicular traffic on paved or unpaved roads at industrial facilities because these are treated as
point sources so they are properly located. Table 2-7 is a listing of the Source Classification Codes
(SCCs) in the afdust sector. For 2018v2 no changes were made from the year 2018 afdust inventory in
2018gc.

Table 2-7. Afdust sector SCCs

sec

Tier 1
description

Tier 2
description

Tier 3 description

Tier 4 description

2294000000

Mobile Sources

Paved Roads

All Paved Roads

Total: Fugitives

2296000000

Mobile Sources

Unpaved Roads

All Unpaved Roads

Total: Fugitives

2311010000

Industrial
Processes

Construction: SIC
15-17

Residential

Total

2311020000

Industrial
Processes

Construction: SIC
15-17

Industrial/Commercial/
Institutional

Total

2311030000

Industrial
Processes

Construction: SIC
15-17

Road Construction

Total

2325000000

Industrial
Processes

Mining and
Quarrying: SIC 14

All Processes

Total

29


-------
sec

Tier 1
description

Tier 2
description

Tier 3 description

Tier 4 description

2325020000

Industrial
Processes

Mining and
Quarrying: SIC 14

Crushed and Broken Stone

Total

2325030000

Industrial
Processes

Mining and
Quarrying: SIC 14

Sand and Gravel

Total

2325060000

Industrial
Processes

Mining and
Quarrying: SIC 10

Lead Ore Mining and Milling

Total

2801000000

Miscellaneous
Area Sources

Ag. Production -
Crops

Agriculture - Crops

Total

2801000003

Miscellaneous
Area Sources

Ag. Production -
Crops

Agriculture - Crops

Tilling

2801000005

Miscellaneous
Area Sources

Ag. Production -
Crops

Agriculture - Crops

Harvesting

2801000008

Miscellaneous
Area Sources

Ag. Production -
Crops

Agriculture - Crops

Transport

2805001000

Miscellaneous
Area Sources

Ag. Production -
Livestock

Beef cattle - finishing
operations on feedlots (drylots)

Dust Kicked-up by Hooves
(use 28-05-020, -001, -002, or
-003 for Waste

2805001010

Miscellaneous
Area Sources

Ag. Production -
Livestock

Dairy Cattle

Dust Kicked-up by Hooves

2805001020

Miscellaneous
Area Sources

Ag. Production -
Livestock

Broilers

Dust Kicked-up by Feet

2805001030

Miscellaneous
Area Sources

Ag. Production -
Livestock

Layers

Dust Kicked-up by Feet

2805001040

Miscellaneous
Area Sources

Ag. Production -
Livestock

Swine

Dust Kicked-up by Hooves

2805001050

Miscellaneous
Area Sources

Ag. Production -
Livestock

Turkeys

Dust Kicked-up by Feet

Area Fugitive Dust Transport Fraction

The afdust sector is separated from other nonpoint sectors to allow for the application of a "transport
fraction," and meteorological/precipitation reductions. These adjustments are applied using a script that
applies land use-based gridded transport fractions based on landscape roughness, followed by another
script that zeroes out emissions for days on which at least 0.01 inches of precipitation occurs or there is
snow cover on the ground. The land use data used to reduce the NEI emissions determines the amount of
emissions that are subject to transport. This methodology is discussed in Pouliot, et al., 2010, and in
"Fugitive Dust Modeling for the 2008 Emissions Modeling Platform" (Adelman, 2012). Both the
transport fraction and meteorological adjustments are based on the gridded resolution of the platform (i.e.,
12km grid cells); therefore, different emissions will result if the process were applied to different grid
resolutions. A limitation of the transport fraction approach is the lack of monthly variability that would be
expected with seasonal changes in vegetative cover. While wind speed and direction are not accounted for
in the emissions processing, the hourly variability due to soil moisture, snow cover and precipitation is
accounted for in the subsequent meteorological adjustment.

Paved road dust emissions were projected from the 2017 NEI (January 2021 version) to 2018 based on
county-level VMT trends. For the data compiled into the 2017 NEI, meteorological adjustments are
applied to paved and unpaved road SCCs but not transport adjustments. The meteorological adjustments
that were applied (to paved and unpaved road SCCs) were backed out so that the entire sector could be
processed consistently in SMOKE and the same grid-specific transport fractions and meteorological
adjustments could be applied sector-wide. Thus, the FF10 that is run through SMOKE consists of 100%

30


-------
unadjusted emissions, and after SMOKE all afdust sources have both transport and meteorological
adjustments applied. The total impacts of the transport fraction and meteorological adjustments are shown
in Table 2-8. Note that while totals from AK, HI, PR, and VI are included at the bottom of the table, they
are from non-continental U.S. (non-CONUS) modeling domains and are not included in this modeling.

Table 2-8. Total impact of fugitive dust adjustments to the unadjusted 2018 inventory

Sliilc

I iiiidjiislcd

PMio

I iiiidjuslcd

PM2.5

Ch.ingi' in
PM10

Ch.ingi' in
P\i: 5

PM10
Reduction

I'M:.?
Rcduclion

Alabama

305,367

41,144

-230,323

-31,003

75%

75%

Arizona

181,909

24,406

-66,546

-8,746

37%

36%

Arkansas

394,141

54,562

-291,744

-39,859

74%

73%

California

310,409

39,283

-129,849

-15,926

42%

41%

Colorado

282,333

41,177

-138,166

-19,575

49%

48%

Connecticut

24,373

4,018

-20,564

-3,402

84%

85%

Delaware

15,399

2,363

-10,975

-1,698

71%

72%

District of
Columbia

2,904

408

-2,045

-287

70%

70%

Florida

399,417

55,840

-232,626

-32,611

58%

58%

Georgia

296,293

42,313

-221,055

-31,383

75%

74%

Idaho

566,157

65,518

-293,324

-32,981

52%

50%

Illinois

1,113,448

160,670

-743,938

-106,939

67%

67%

Indiana

145,326

27,135

-104,222

-19,547

72%

72%

Iowa

388,521

57,174

-272,484

-40,050

70%

70%

Kansas

671,159

89,522

-326,621

-43,144

49%

48%

Kentucky

177,791

29,057

-143,563

-23,399

81%

81%

Louisiana

180,054

27,493

-124,363

-18,843

69%

69%

Maine

71,361

8,748

-62,096

-7,617

87%

87%

Maryland

75,016

12,001

-55,750

-8,968

74%

75%

Massachusetts

63,362

9,769

-53,378

-8,193

84%

84%

Michigan

295,317

38,890

-226,158

-29,569

77%

76%

Minnesota

426,574

60,081

-322,412

-45,022

76%

75%

Mississippi

450,394

55,051

-334,736

-40,639

74%

74%

Missouri

1,343,746

159,274

-923,739

-109,115

69%

69%

Montana

503,637

66,766

-315,146

-40,657

63%

61%

Nebraska

518,777

71,853

-287,865

-39,258

55%

55%

Nevada

137,960

18,342

-45,995

-6,095

33%

33%

New Hampshire

20,797

4,369

-18,572

-3,901

89%

89%

New Jersey

32,650

6,098

-25,454

-4,715

78%

77%

New Mexico

212,784

26,470

-81,954

-10,159

39%

38%

New York

235,609

33,253

-196,117

-27,572

83%

83%

North Carolina

237,482

32,163

-177,764

-24,084

75%

75%

31


-------
Stale

I nad.jiislcd

PMu.

I nad.jiislcd

I'M:..*

Chanel' in
PMu.

Chanel' in
I'M:?

PMio
Reduction

PM:;
Reduction

North Dakota

392,449

60,817

-249,067

-38,155

63%

63%

Ohio

273,606

42,727

-208,705

-32,606

76%

76%

Oklahoma

606,070

82,689

-324,863

-43,387

54%

52%

Oregon

611,834

69,018

-391,320

-43,250

64%

63%

Pennsylvania

136,244

24,437

-114,081

-20,670

84%

85%

Rhode Island

4,674

780

-3,735

-624

80%

80%

South Carolina

120,222

16,728

-85,592

-11,963

71%

72%

South Dakota

216,781

38,647

-127,869

-22,524

59%

58%

Tennessee

142,420

26,141

-109,301

-20,163

77%

77%

Texas

1,345,665

195,743

-683,391

-96,971

51%

50%

Utah

170,178

21,730

-84,218

-10,590

49%

49%

Vermont

76,848

8,552

-68,663

-7,617

89%

89%

Virginia

126,183

20,340

-101,285

-16,401

80%

81%

Washington

233,671

38,073

-127,588

-20,758

55%

55%

West Virginia

85,562

11,078

-77,773

-10,070

91%

91%

Wisconsin

184,558

31,386

-138,771

-23,555

75%

75%

Wyoming

545,710

61,315

-285,547

-31,827

52%

52%

Domain Total
(12km CONUS)

15,353,146

2,115,413

-9,661,314

-1,326,091

63%

63%

Alaska

107,706

11,726

-99,218

-10,749

92%

92%

Hawaii

18,243

2,381

-10,203

-1,359

56%

57%

Puerto Rico

1,138,725

152,073

-1,079,286

-144,873

95%

95%

Virgin Islands

1,777

245

-860

-120

48%

49%

Figure 2-1 illustrates the impact of each step of the adjustment. The reductions due to the transport
fraction adjustments alone are shown at the top of the figure. The reductions due to the precipitation
adjustments alone are shown in the middle of the figure. The cumulative emission reductions after both
transport fraction and meteorological adjustments are shown at the bottom of the figure. The top plot
shows how the transport fraction has a larger reduction effect in the east, where forested areas are more
effective at reducing PM transport than in many western areas. The middle plot shows how the
meteorological impacts of precipitation, along with snow cover in the north, further reduce the dust
emissions.

32


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Figure 2-1. Impact of adjustments to fugitive dust emissions due to transport fraction and

precipitation

2018gc afdust annual : PM2 5, xportfrac adjusted - unadjusted

Max: 0.0 Min: -1835.166'

2018gc afdust annual : PM2 5, precip adjusted - xportfrac adjusted

Max: 0.0 Min: -1782

33


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2018gc afdust annual : PM2 5, xportfrac + precip adjusted - unadjusted

2.2.2 Agricultural Livestock (livestock)

The livestock sector includes NHS emissions from fertilizer and emissions of all pollutants other than
PM2.5 from livestock in the nonpoint (county-level) data category of the 2017NEI. PM2.5 from livestock
are in the Area Fugitive Dust (afdust) sector. Combustion emissions from agricultural equipment, such as
tractors, are in the nonroad sector.

The SCCs included in the livestock sector are shown in Table 2-9. The livestock SCCs are related to beef
and dairy cattle, poultry production and waste, swine production, waste from horses and ponies, and
production and waste for sheep, lambs, and goats. The sector does not include quite all of the livestock
NH3 emissions, as there is a very small amount of NH3 emissions from livestock in the ptnonipm
inventory (as point sources). In addition to NEb.the sector includes livestock emissions from all pollutants
other than PM2.5. PM2.5 from livestock are in the afdust sector. For 2018v2, corrections were made to the
livestock emissions in Maryland and Illinois. Otherwise, the livestock emissions are unchanged from
those in 2018gc.

Table 2-9. SCCs for the livestock sector

see

Tier 1 description

Tier 2 description

Tier 3 description

Tier 4 description

2805002000

Miscellaneous Area
Sources

Ag. Production -
Livestock

Beef cattle production
composite

Not Elsewhere Classified

2805007100

Miscellaneous Area
Sources

Ag. Production -
Livestock

Poultry production - layers
with dry manure management
systems

Confinement

2805009100

Miscellaneous Area
Sources

Ag. Production -
Livestock

Poultry production - broilers

Confinement

34


-------
S( (

Tier 1 description

Tier 2 description

Tier 3 description

Tier 4 description

2805010100

Miscellaneous Area
Sources

Ag. Production -
Livestock

Poultry production - turkeys

Confinement

2805018000

Miscellaneous Area
Sources

Ag. Production -
Livestock

Dairy cattle composite

Not Elsewhere Classified

2805025000

Miscellaneous Area
Sources

Ag. Production -
Livestock

Swine production composite

Not Elsewhere Classified
(see also 28-05-039, -047, -
053)

2805035000

Miscellaneous Area
Sources

Ag. Production -
Livestock

Horses and Ponies Waste
Emissions

Not Elsewhere Classified

2805040000

Miscellaneous Area
Sources

Ag. Production -
Livestock

Sheep and Lambs Waste
Emissions

Total

2805045000

Miscellaneous Area
Sources

Ag. Production -
Livestock

Goats Waste Emissions

Not Elsewhere Classified

Agricultural livestock emissions in the 2018 platform were projected from the 2017 NEI (January 2021
version), which is a mix of state-submitted data and EPA estimates. USDA Survey data for 2017 and
2018 was used to create projection factors (https://quickstats.nass.usda.gov/). The resulting projections
factors are shown in Table 2-10. Livestock emissions utilized improved animal population data. VOC
livestock emissions, new for this sector, were estimated by multiplying a national VOC/NH3 emissions
ratio by the county NH3 emissions. The 2017 NEI approach for livestock utilizes daily emission factors by
animal and county from a model developed by Carnegie Mellon University (CMU) (Pinder, 2004,
McQuilling, 2015) and 2017 U.S. Department of Agriculture (USDA) National Agricultural Statistics
Service (NASS) survey. Details on the approach are provided in Section 4.5 of the 2017 NEI TSD. The
livestock sector includes VOC and HAP VOC in addition to NH3.

Table 2-10. National projection factors for livestock: 2017 to 2018

beef

+0.74%

swine

+2.66%

broilers

+2.18%

turkeys

-1.37%

layers

+2.19%

dairy

+0.55%

2.2.3 Agricultural Fertilizer (fertilizer)

Using the same method described in the 2017 NEI TSD, fertilizer emissions for 2018 are based on the
FEST-C model (https://www.cmascenter.org/fest-c/). Unlike most of the other emissions that are input to
the CMAQ model, fertilizer emissions are actually output from a run of CMAQ in bi-directional mode
and summarized for inclusion with the rest of the emissions. The bidirectional version of CMAQ (v5.3)
and the Fertilizer Emissions Scenario Tool for CMAQ FEST-C (vl.3) were used to estimate ammonia
(NH3) emissions from agricultural soils. The computed emissions were saved during the CMAQ run for
the purposes of summaries and other model runs that did not use the bidirectional method.

Fertilizer emissions are associated with the SCC 2801700099 (Miscellaneous Area Sources; Ag.
Production - Crops; Fertilizer Application; Miscellaneous Fertilizers).

The approach to estimate year-specific fertilizer emissions consists of these steps:

35


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•	Run FEST-C to produce nitrate (N03), Ammonium (NH4+, including Urea), and organic
(manure) nitrogen (N) fertilizer usage estimates.

•	Run the CMAQ model with bidirectional ("bidi") NH3 exchange to generate gaseous ammonia
NHS emission estimates.

•	Calculate county-level emission factors as the ratio of bidirectional CMAQ NH3 fertili zer
emissions to FEST-C total N fertilizer application.

FEST-C is the software program that processes land use and agricultural activity data to develop inputs
for the CMAQ model when run with bidirectional exchange. FEST-C reads land use data from the
Biogenic Emissions Landuse Dataset (BELD), meteorological variables from the Weather Research and
Forecasting (WRF) model, and nitrogen deposition data from a previous or historical average CMAQ
simulation. FEST-C, then uses the Environmental Policy Integrated Climate (EPIC) modeling system
(https://epicapex.tamu.edu/epic/) to simulate the agricultural practices and soil biogeochemistry and
provides information regarding fertilizer timing, composition, application method and amount.

As illustrated in Figure 2-2, an iterative calculation was applied to estimate fertilizer emissions for the
platform. First, fertilizer application by crop type was estimated using FEST-C modeled data. Then
CMAQ v5.3 was run with the Surface Tiled Aerosol and Gaseous Exchange (STAGE) deposition option
with bidirectional exchange to estimate fertilizer and biogenic NHS emissions.

Figure 2-2. "Bidi" modeling system used to compute fertilizer application emissions

The Fertilizer Emission Scenario Tool for CMAQ

(FEST-C)

36


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Fertilizer Activity Data

The following activity parameters were input into the EPIC model:

•	Grid cell meteorological variables from WRF

•	Initial soil profiles/soil selection

•	Presence of 21 major crops: irrigated and rain fed hay, alfalfa, grass, barley, beans, grain corn,
silage corn, cotton, oats, peanuts, potatoes, rice, rye, grain sorghum, silage sorghum, soybeans,
spring wheat, winter wheat, canola, and other crops (e.g., lettuce, tomatoes, etc.)

•	Fertilizer sales to establish the type/composition of nutrients applied

•	Management scenarios for the 10 USDA production regions. These include irrigation, tile
drainage, intervals between forage harvest, fertilizer application method (injected versus surface
applied), and equipment commonly used in these production regions.

The WRF meteorological model was used to provide grid cell meteorological parameters for the base year
using a national 12-km rectangular grid covering the continental U.S. The meteorological parameters in
Table 2-11 were used as EPIC model inputs.

Table 2-11. Source of input variables for EPIC

EPIC input variable

Variable Source

Daily Total Radiation (MJ/m2 )

WRF

Daily Maximum 2-m Temperature (C)

WRF

Daily minimum 2-m temperature (C)

WRF

Daily Total Precipitation (mm)

WRF

Daily Average Relative Humidity (unitless)

WRF

Daily Average 10-m Wind Speed (m s"1 )

WRF

Daily Total Wet Deposition Oxidized N (g/ha)

CMAQ

Daily Total Wet Deposition Reduced N (g/ha)

CMAQ

Daily Total Dry Deposition Oxidized N (g/ha)

CMAQ

Daily Total Dry Deposition Reduced N (g/ha)

CMAQ

Daily Total Wet Deposition Organic N (g/ha)

CMAQ

Initial soil nutrient and pH conditions in EPIC were based on the 1992 USDA Soil Conservation Service
(CSC) Soils-5 survey. The EPIC model was then run for 25 years using current fertilization and
agricultural cropping techniques to estimate soil nutrient content and pH.

The presence of crops in each model grid cell was determined using USDA Census of Agriculture data
(2012) and USGS National Land Cover data (2011). These two data sources were used to compute the
fraction of agricultural land in a model grid cell and the mix of crops grown on that land.

Fertilizer sales data and the 6-month period in which they were sold were extracted from the 2014
Association of American Plant Food Control Officials (AAPFCO,

http://www.aapfco.org/publications.htmn. AAPFCO data were used to identify the composition (e.g.,
urea, nitrate, organic) of the fertilizer used, and the amount applied is estimated using the modeled crop

37


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demand. These data were useful in making a reasonable assignment of what kind of fertilizer is being
applied to which crops.

Management activity data refers to data used to estimate representative crop management schemes. The
USD A Agricultural Resource Management Survey (ARMS,

https://www.nass.usda.gov/Survevs/Guide to NASS Survevs/Ag Resource Management/) was used to
provide management activity data. These data cover 10 USD A production regions and provide
management schemes for irrigated and rain fed hay, alfalfa, grass, barley, beans, grain corn, silage corn,
cotton, oats, peanuts, potatoes, rice, rye, grain sorghum, silage sorghum, soybeans, spring wheat, winter
wheat, canola, and other crops (e.g., lettuce, tomatoes, etc.).

2.2.4 Nonpoint Oil and Gas (np_oilgas)

While the major emissions sources associated with oil and gas collection, processing, and distribution
have traditionally been included in the National Emissions Inventory (NEI) as point sources (e.g., gas
processing plants, pipeline compressor stations, and refineries), the activities occurring "upstream" of
these types of facilities have not been as well characterized in the NEI. Here, upstream activities refer to
emission units and processes associated with the exploration and drilling of oil and gas wells, and the
equipment used at the well site to then extract the product from the well and deliver it to a central
collection point or processing facility. The types of unit processes found at upstream sites include
separators, dehydrators, storage tanks, and compressor engines.

The nonpoint oil and gas (np oilgas) sector, which consists of oil and gas exploration and production
sources, both onshore and offshore (state-owned only). For many states, these emissions are mostly based
on the EPA Oil and Gas Tool run with data specific to the year 2018. Because of the growing importance
of these emissions, special consideration is given to the speciation, spatial allocation, and monthly
temporalization of nonpoint oil and gas emissions, instead of relying on older, more generalized profiles.

EPA Oil and Gas Tool

EPA developed the 2018 non-point oil and gas inventory for the 2018v2 platform using the 2017NEI
version of the Oil and Gas Emission Estimation Tool (the "Tool") with year 2018 oil and gas production
and exploration activity as input into the Tool. The Tool was previously used to estimate emissions for the
2017 NEI. Year 2018 oil and gas activity data were supplied to EPA by some state air agencies, and
where state data were not supplied to EPA, EPA populated the 2018v2 inventory with the best available
data. The Tool is an Access database that utilizes county-level activity data (e.g., oil production and well
counts), operational characteristics (types and sizes of equipment), and emission factors to estimate
emissions. The Tool creates a CSV-formatted emissions dataset covering all national nonpoint oil and gas
emissions. This dataset is then converted to FF10 format for use in SMOKE modeling. A separate report
named "2017 Nonpoint Oil and Gas Emission Estimation Tool Revisions Vl 41 l_2019.docx" (ERG,
2019a) was generated that provides technical details of how the tool was applied for the 2017NEI. The
2017 NEI Tool document can be found at:

https://gaftp.epa.gov/air/nei/2017/doc/supporting data/nonpoint/.

Nonpoint Oil and Gas Alternative Datasets

Some states provided, or recommended use of, a separate emissions inventory for use in 2018v2 platform
instead of emissions derived from the EPA Oil and Gas Tool. The 2017NEI oil and gas emissions for

38


-------
production-related sources were used for the states of California, Colorado, Oklahoma, Texas, Utah and
Wyoming. New Mexico and North Dakota used the WRAP inventory used in the 2016v3 modeling for
production-related sources. Emissions from exploration-related sources can vary year to year more so than
production-related sources, so the 2018 Oil and Gas Tool emissions for exploration-related sources were
used for every state for the 2018v2 modeling platform.

In Pennsylvania for the 2018v2 modeling platform, the emissions associated with unconventional wells
for year 2018 were supplied by the Pennsylvania Department of Environmental Protection (PA DEP). The
Oil and Gas Tool was used to produce the conventional well emissions for 2018. Together these
unconventional and conventional well emissions represent the total non-point oil and gas emissions for
Pennsylvania.

2.2.5 Residential Wood Combustion (rwc)

The RWC sector includes residential wood burning devices such as fireplaces, fireplaces with inserts, free
standing woodstoves, pellet stoves, outdoor hydronic heaters (also known as outdoor wood boilers),
indoor furnaces, and outdoor burning in firepits and chimneys. Free standing woodstoves and inserts are
further differentiated into three categories: 1) conventional (not EPA certified); 2) EPA certified,
catalytic; and 3) EPA certified, noncatalytic. Generally, the conventional units were constructed prior to
1988. Units constructed after 1988 had to meet EPA emission standards and they are either catalytic or
non-catalytic.

The 2018 platform RWC emissions are unchanged from the data in the 2017 NEI. Some improvements to
RWC emissions estimates were made for the 2017 NEI and were included in this study. The EPA, along
with the Commission on Environmental Cooperation (CEC), the Northeast States for Coordinated Air Use
Management (NESCAUM), and Abt Associates, conducted a national survey of wood-burning activity in
2018. The results of this survey were used to estimate county-level burning activity data. The activity data
for RWC processes is the amount of wood burned in each county, which is based on data from the CEC
survey on the fraction of homes in each county that use each wood-burning appliance and the average
amount of wood burned in each appliance. These assumptions are used with the number of occupied
homes in each county to estimate the total amount of wood burned in each county, in cords for cordwood
appliances and tons for pellet appliances. Cords of wood are converted to tons using county-level density
factors from the U.S. Forest Service. RWC emissions were calculated by multiplying the tons of wood
burned by emissions factors. For more information on the development of the residential wood
combustion emissions, see Section 4.15 of the 2017 NEI TSD

The source classification codes (SCCs) in the RWC sector are listed in Table 2-12. For both 2018gc and
2018v2, the emissions use the 2017 NEI.

Table 2-12. SCCs for the residential wood combustion sector

SCC

Tier 1 Description

Tier 2
Description

Tier 3
Description

Tier 4 Description

2104008100

Stationary Source
Fuel Combustion

Residential

Wood

Fireplace: general

2104008210

Stationary Source
Fuel Combustion

Residential

Wood

Woodstove: fireplace inserts;
non-EPA certified

2104008220

Stationary Source
Fuel Combustion

Residential

Wood

Woodstove: fireplace inserts;
EPA certified; non-catalytic

39


-------
S( (

Tier 1 Description

Tier 2
Description

Tier 3
Description

Tier 4 Description

2104008230

Slaliuiiary Suui'ce
Fuel Combustion

Residential

Wood

Wuudsluve. fireplace inserts,
EPA certified; catalytic

2104008310

Stationary Source
Fuel Combustion

Residential

Wood

Woodstove: freestanding, non-
EPA certified

2104008320

Stationary Source
Fuel Combustion

Residential

Wood

Woodstove: freestanding, EPA
certified, non-catalytic

2104008330

Stationary Source
Fuel Combustion

Residential

Wood

Woodstove: freestanding, EPA
certified, catalytic

2104008400

Stationary Source
Fuel Combustion

Residential

Wood

Woodstove: pellet-fired, general
(freestanding or FP insert)

2104008510

Stationary Source
Fuel Combustion

Residential

Wood

Furnace: Indoor, cordwood-fired,
non-EPA certified

2104008610

Stationary Source
Fuel Combustion

Residential

Wood

Hydronic heater: outdoor

2104008700

Stationary Source
Fuel Combustion

Residential

Wood

Outdoor wood burning device,
NEC (fire-pits, chimineas, etc)

2104009000

Stationary Source
Fuel Combustion

Residential

Firelog

Total: All Combustor Types

2.2.6 Solvents (np_solvents)

The npsolvents sector includes a diverse collection of sources for which emissions are driven by
evaporation. Included in this sector are everyday items such as cleaners, personal care products,
adhesives, architectural and aerosol coatings, printing inks, and pesticides. These sources exclusively emit
organic gases (i.e., VOCs) with origins spanning residential, commercial, institutional, and industrial
settings. The organic gases that evaporate from these sources often fulfill other functions than acting as a
traditional solvent (e.g., propellants, fragrances, emollients); as such, these emissions are frequently
described as volatile chemical products (VCPs).

The types of sources in the np solvents sector include, but are not limited to, solvent utilization for the
following:

•	surface coatings such as architectural coatings, auto refinishing, traffic marking, textile
production, furniture finishing, and coating of paper, plastic, metal, appliances, and motor
vehicles;

•	degreasing of furniture, metals, auto repair, electronics, and manufacturing;

•	dry cleaning, graphic arts, plastics, industrial processes, personal care products, household
products, adhesives and sealants; and

•	asphalt application, roofing asphalt, and pesticide application.

For the 2018v2 platform, emissions for the np solvents sector are derived using the VCPy framework
(Seltzer et al., 2021). The VCPy framework is based on the principle that the magnitude and speciation of
organic emissions from this sector are directly related to (1) the mass of chemical products used, (2) the
composition of these products, (3) the physiochemical properties of their constituents that govern
volatilization, and (4) the timescale available for these constituents to evaporate. National product usage is
preferentially estimated using economic statistics from the U.S. Census Bureau's Annual Survey of
Manufacturers (U.S. Census Bureau, 2021), commodity prices from the U.S. Department of

40


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Transportation's 2012 Commodity Flow Survey (U.S. Department of Transportation, 2015) and the U.S.
Census Bureau's Paint and Allied Products Survey (U.S. Census Bureau, 2011), and producer price
indices, which scale commodity prices to target years and are retrieved from the Federal Reserve Bank of
St. Louis (U.S. Bureau of Labor Statistics, 2020).

When national product usage data are unavailable, default usage estimates were derived using functional
solvent usage reported by a business research company (The Freedonia Group, 2016) or in sales reported
in a California Air Resources Board (CARB) California-specific survey (CARB, 2019). The composition
of products is estimated by generating composites from various CARB surveys (CARB, 2007; CARB,
2012; CARB 2014; CARB, 2018; CARB, 2019) and profiles reported in the U.S. EPA's SPECIATE
database (EPA, 2019). The physiochemical properties of all organic components are generated from the
quantitative structure-activity relationship model OPERA (Mansouri et al., 2018) and the characteristic
evaporation timescale of each component is estimated using previously published methods (Khare and
Gentner, 2018; Weschler and Nazaroff, 2008). All methods are thoroughly documented in Section 32 of
the 2020 NEI Technical Source Document.

National-level emissions estimates were allocated to the county-level using several proxies. Most
emissions are allocated using population as an allocation surrogate. This includes all cleaners, personal
care products, adhesives, architectural coatings, and aerosol coatings. Industrial coatings, printing inks,
and dry-cleaning emissions are allocated using county-level employment statistics from the U.S. Census
Bureau's County Business Patterns (U.S. Census Bureau, 2018) and follow the same mapping scheme
used in the EPA's 2020 National Emissions Inventory (EPA, 2023b). Agricultural pesticides are allocated
using county-level agricultural pesticide use, as taken from the 2017 NEI and traffic marking coatings are
allocated using estimates of vehicular lane miles traveled on paved roads from the Federal Highway
Administration and MOVES model. All activity data reflects the most recently available dataset.

In addition, point and nonpoint emissions for which SCCs overlap are reconciled using point source
subtraction. Point source subtraction was performed at the county-level using estimates of uncontrolled
point source emissions. Uncontrolled point source emission calculations were calculated, as necessary,
using the submitted point source emissions, engineering judgement, and an assumed control efficiency.

2.2.7 Nonpoint (nonpt)

The 2018 platform nonpt sector inventory is mostly unchanged from the January 2021 version of the 2017
NEI, aside from the removal of emissions from accidental releases in a few states. The nonpt sector
includes all nonpoint sources that are not included in the sectors afdust, livestock, fertilizer, cmv_clc2,
cmv_c3, np oilgas, rail, rwc, or np solvents. The types of sources in the nonpt sector include, but are not
limited to:

•	stationary source fuel combustion, including industrial, commercial, and residential and orchard
heaters;

•	commercial sources such as commercial cooking;

•	industrial processes such as chemical manufacturing, metal production, mineral processes,
petroleum refining, wood products, fabricated metals, and refrigeration;

•	storage and transport of petroleum for uses such as gasoline service stations, aviation, and marine
vessels;

•	storage and transport of chemicals;

41


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•	waste disposal (including composting);

•	miscellaneous non-industrial sources such as cremation, hospitals, lamp breakage, and automotive
repair shops;

•	bulk gasoline terminals;

•	portable fuel containers (i.e., gas cans);

•	cellulosic biorefining;

•	biomass fuel combustion;

•	stage 1 refueling emissions at gas stations;

•	and any construction agricultural dust that is not part of the area fugitive dust or livestock sectors.

2.3 Onroad Mobile sources (onroad)

Onroad mobile source include emissions from motorized vehicles operating on public roadways. These
include passenger cars, motorcycles, minivans, sport-utility vehicles, light-duty trucks, heavy-duty trucks,
and buses. The sources are further divided by the fuel they use, including diesel, gasoline, E-85, and
compressed natural gas (CNG) vehicles. The sector characterizes emissions from parked vehicle
processes (e.g., starts, hot soak, and extended idle) as well as from on-network processes (i.e., from
vehicles as they move along the roads). For more details on the approach and for a summary of the
MOVES inputs submitted by states, see section 6.5.1 of the 2017 NEI TSD.

For the 2018 modeling platform, VMT were projected from 2017 to 2018 based mostly on Federal
Highways administration (FHWA) annual VMT changes at the county level. In a few cases, state
Department of Transportation (DOT) data were used instead of FHWA data. Other activity data (i.e.,
starts, on-network idling, VPOP, and hoteling) are projected by applying a ratio of 2017-based
VMT/activity ratios to the 2018 VMT. In addition, a number of states submitted 2017-specific activity
data for incorporation into this platform. Finally, a new MOVES run for 2018 was done using MOVES3.

Except for California, all onroad emissions are generated using the SMOKE-MOVES emissions modeling
framework that leverages MOVES-generated emission factors https://www.epa.gov/moves). county and
SCC-specific activity data, and hourly 2018 meteorological data. Specifically, EPA used MOVES3 inputs
for representative counties, vehicle miles traveled (VMT), vehicle population (VPOP), and hoteling hours
data for all counties, along with tools that integrated the MOVES model with SMOKE. In this way, it was
possible to take advantage of the gridded hourly temperature data available from meteorological modeling
that are also used for air quality modeling. The onroad source classification codes (SCCs) in the modeling
platform are more finely resolved than those in the National Emissions Inventory (NEI). The NEI SCCs
distinguish vehicles and fuels. The SCCs used in the model platform also distinguish between emissions
processes (i.e., off-network, on-network, and extended idle), and road types.

MOVES3 includes the following updates from MOVES2014b:

•	Updated emission rates:

o Updated heavy-duty (HD) diesel running emission rates based on manufacturer in-use

testing data from hundreds of HD trucks
o Updated HD gasoline and compressed natural gas (CNG) trucks
o Updated light-duty (LD) emission rates for hydrocarbons (HC), CO, NOx, and PM

42


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•	Includes updated fuel information

•	Incorporates HD Phase 2 Greenhouse Gas (GHG) rule, allowing for finer distinctions among HD
vehicles

•	Accounts for glider vehicles that incorporate older engines into new vehicle chassis

•	Accounts for off-network idling - emissions beyond the idling that is already considered in the
MOVES drive cycle

•	Includes revisions to inputs for hoteling

•	Adds starts as a separate type of rate and activity data

2.3.1 Inventory Development using SMOKE-MOVES

Except for California, onroad emissions were computed with SMOKE-MOVES by multiplying specific
types of vehicle activity data by the appropriate emission factors. This section includes discussions of the
activity data and the emission factor development. The vehicles (aka source types) for which MOVES
computes emissions are shown in Table 2-13. SMOKE-MOVES was run for specific modeling grids.
Emissions for the contiguous U.S. states and Washington, D.C., were computed for a grid covering those
areas. For the portion of Southeast Alaska which lies inside the 36US3 modeling domain, SMOKE-
MOVES was run using meteorology for the 36US3 domain; this extra run is included in the
onroad nonconus sector. In some summary reports these non-CONUS emissions are aggregated with
emissions from the onroad sector.

Table 2-13. MOVES vehicle (source) types

MOYKS vehicle Ivpe

Description

II P.MS vehicle Ivpe

11

Motorcycle

10

21

Passenger Car

25

31

Passenger Truck

25

32

Light Commercial Truck

25

41

Intercity Bus

40

42

Transit Bus

40

43

School Bus

40

51

Refuse Truck

50

52

Single Unit Short-haul Truck

50

53

Single Unit Long-haul Truck

50

54

Motor Home

50

61

Combination Short-haul Truck

60

62

Combination Long-haul Truck

60

SMOKE-MOVES makes use of emission rate "lookup" tables generated by MOVES that differentiate
emissions by process (i.e., running, start, vapor venting, etc.), vehicle type, road type, temperature, speed,
hour of day, etc. To generate the MOVES emission rates that could be applied across the U.S., EPA used
an automated process to run MOVES to produce year 2018-specific emission factors by temperature and
speed for a series of "representative counties," to which every other county was mapped. The
representative counties for which emission factors are generated are selected according to their state,
elevation, fuels, age distribution, ramp fraction, and inspection and maintenance programs. Each county is
then mapped to a representative county based on its similarity to the representative county with respect to
those attributes. For this study, there are 291 representative counties in the continental U.S. and a total of

43


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329 including the non-CONUS areas. The representative counties that were used for the 2018 platform are
very close to what was used in EPA's Air QUAlity TimE Series (EQUATES) project for the years 2016
and 2017 (EPA 2023c). The EPA added some additional representative counties to the set used for
EQUATES to account for altitude and variations in I&M programs and fuels.

Once representative counties have been identified, emission factors are generated with MOVES for each
representative county and for two "fuel months" - January to represent winter months, and July to
represent summer months - due to the different types of fuels used. SMOKE selects the appropriate
MOVES emissions rates for each county, hourly temperature, SCC, and speed bin and then multiplies the
emission rate by appropriate activity data. For on-roadway emissions, vehicle miles travelled (VMT) is
the activity data, vehicle population (VPOP) is used for many off-network processes, and hoteling hours
are used to develop emissions for extended idling of combination long-haul trucks. These calculations are
done for every county and grid cell in the continental U.S. for each hour of the year.

The SMOKE-MOVES process for creating the model-ready emissions consists of the following steps:

1)	Determine which counties will be used to represent other counties in the MOVES runs.

2)	Determine which months will be used to represent other month's fuel characteristics.

3)	Create inputs needed only by MOVES. MOVES requires county-specific information on vehicle
populations, age distributions, and inspection-maintenance programs for each of the
representative counties.

4)	Create inputs needed both by MOVES and by SMOKE, including temperatures and activity
data.

5)	Run MOVES to create emission factor tables for the temperatures found in each county.

6)	Run SMOKE to apply the emission factors to activity data (VMT, VPOP, STARTS, off-network
idling, and HOTELING) to calculate emissions based on the gridded hourly temperatures in the
meteorological data.

7)	Aggregate the results to the county-SCC level for summaries and quality assurance.

The onroad emissions are processed in six processing streams that are merged together into the onroad
sector emissions after each of the six streams have been processed:

•	rate-per-distance (RPD) uses VMT as the activity data plus speed and speed profile information to
compute on-network emissions from exhaust, evaporative, permeation, refueling, and brake and
tire wear processes;

•	rate-per-vehicle (RPV) uses VPOP activity data to compute off-network emissions from exhaust,
evaporative, permeation, and refueling processes;

•	rate-per-profile (RPS) uses STARTS activity data to compute off-network emissions from vehicles
starts;

•	rate-per-profile (RPP) uses VPOP activity data to compute off-network emissions from
evaporative fuel vapor venting, including hot soak (immediately after a trip) and diurnal (vehicle
parked for a long period) emissions;

•	rate-per-hour (RPH) uses hoteling hours activity data to compute off-network emissions for idling
of long-haul trucks from extended idling and auxiliary power unit process; and

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•	rate-per-hour off-network idling (RPHO) uses off network idling hours activity data to compute
off-network idling emissions for all types of vehicles.

The onroad emissions inputs to MOVES for the 2018 platform are based on the 2017 NEI, development
of which is described in more detail in Section 6 of the 2017 NEI TSD. These inputs include:

•	Key parameters in the MOVES County databases (CDBs) including Low Emission Vehicle (LEV)
table

•	Fuel months

•	Activity data (e.g., VMT, VPOP, speed, HOTELING)

Fuel months and other inputs were consistent with those in the 2017 NEI. Age distributions in the
MOVES databases were adjusted to represent the year 2018. States that submitted activity data and
development of the EPA default activity data sets for VMT, VPOP, and hoteling hours are described in
detail in the 2017 NEI TSD and supporting documents. Hoteling hours activity are used to calculate
emissions from extended idling and auxiliary power units (APUs) by combination long-haul trucks.

2.3.2 Onroad Activity Data Development

SMOKE-MOVES uses vehicle miles traveled (VMT), vehicle population (VPOP), vehicle starts, hours of
off-network idling (ONI), and hours of hoteling, to calculate emissions. These datasets are collectively
known as "activity data." For each of these activity datasets, first a national dataset was developed; this
national dataset is called the "EPA default" dataset. The default dataset started with the 2017 NEI activity
data, which was supplemented with data submitted by state and local agencies. EPA default activity was
used for California, but the emissions were scaled to California-supplied values during the emissions
processing.

Vehicle Miles Traveled (VMT) and Vehicle Population (VPOP)

States that submitted activity data and development of the EPA default activity data sets for VMT, VPOP,
and hoteling hours are described in detail in the 2017 NEI TSD (EPA, 2021) and supporting documents.
For the 2018 modeling platform, VMT were projected from 2017 to 2018 based mostly on Federal
Highways administration (FHWA) annual VMT changes at the county level. In Georgia, state Department
of Transportation (DOT) data were used instead of FHWA data. In Oklahoma, human population trends
were used.

Speed Activity (SPEED/SPDIST)

In SMOKE 4.7, SMOKE-MOVES was updated to use speed distributions similarly to how they are used
when running MOVES in inventory mode. This new speed distribution file, called SPDIST, specifies the
amount of time spent in each MOVES speed bin for each county, vehicle (aka source) type, road type,
weekday/weekend, and hour of day. This file contains the same information at the same resolution as the
Speed Distribution table used by MOVES but is reformatted for SMOKE. Using the SPDIST file results
in a SMOKE emissions calculation that is more consistent with MOVES than the old hourly speed profile
(SPDPRO) approach, because emission factors from all speed bins can be used, rather than interpolating
between the two bins surrounding the single average speed value for each hour as is done with the
SPDPRO approach.

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As was the case with the previous SPDPRO approach, the SPEED inventory that includes a single overall
average speed for each county, SCC, and month, must still be read in by the SMOKE program Smkinven.
SMOKE requires the SPEED dataset to exist even when speed distribution data are available, even though
only the speed distribution data affects the selection of emission factors. The SPEED and SPDIST for
2017NEI are based on a combination of the CRC A-100 (CRC, 2017) project data and 2017 NEI MOVES
CDBs.

Hoteline Hours (HOTELING)

Hoteling hours were capped by county at a theoretical maximum and any excess hours of the maximum
were reduced. For calculating reductions, a dataset of truck stop parking space availability was used,
which includes a total number of parking spaces per county. This same dataset is used to develop the
spatial surrogate for allocating county-total hoteling emissions to model grid cells. The parking space
dataset includes several recent updates based on new truck stops opening and other new information.
There are 8,760 hours in the year 2018; therefore, the maximum number of possible hoteling hours in a
particular county is equal to 8,760 * the number of parking spaces in that county. Hoteling hours were
capped at that theoretical maximum value for 2017 in all counties, with some exceptions.

Because the truck stop parking space dataset may be incomplete in some areas, and trucks may sometimes
idle in areas other than designated spaces, it was assumed that every county has at least 12 parking spaces,
even if fewer parking spaces are found in the parking space dataset. Therefore, hoteling hours are never
reduced below 105,408 hours for the year in any county. If the unreduced hoteling hours were already
below that maximum, the hours were left unchanged; in other words, hoteling activity are never increased
as a result of this analysis. Four states requested that no reductions be applied to the hoteling activity
based on parking space availability: CO, ME, NJ, and NY. For these states, reductions based on parking
space availability were not applied.

The final step related to hoteling activity is to split county totals into separate values for extended idling
(SCC 2202620153) and Auxiliary Power Units (APUs) (SCC 2202620191). New Jersey's submittal of
hoteling activity specified a 30% APU split, and this was used throughout NJ. For the rest of the country,
a 12.4% APU split was used, meaning that during 12.4% of the hoteling hours auxiliary power units are
assumed to be running.

Starts

Onroad "start" emissions are the instantaneous exhaust emissions that occur at the engine start (e.g., due
to the fuel rich conditions in the cylinder to initiate combustion) as well as the additional running exhaust
emissions that occur because the engine and emission control systems have not yet stabilized at the
running operating temperature. Operationally, start emissions are defined as the difference in emissions
between an exhaust emissions test with an ambient temperature start and the same test with the
engine and emission control systems already at operating temperature. As such, the units for start
emission rates are instantaneous grams/start.

MOVES3 uses vehicle population information to sort the vehicle population into source bins defined
by vehicle source type, fuel type (gas, diesel, etc.), regulatory class, model year and age. The model uses
default data from instrumented vehicles (or user-provided values) to estimate the number of starts for
each source bin and to allocate them among eight operating mode bins defined by the amount of time

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parked ("soak time") prior to the start. Thus, MOVES3 accounts for different amounts of cooling of the
engine and emission control systems. Each source bin and operating mode has an associated g/start
emission rate. Start emissions are also adjusted to account for fuel characteristics, LD inspection and
maintenance programs, and ambient temperatures.

2018 STARTS = 2018 VMT * (2017 STARTS/ 2017 VMT by county&SCC6)

Off-network Idlins Hours

After creating VMT inputs for SMOKE-MOVES, Off-network idle (ONI) activity data were also needed.
ONI is defined in MOVES as time during which a vehicle engine is running idle and the vehicle is
somewhere other than on the road, such as in a parking lot, a driveway, or at the side of the road. This
engine activity contributes to total mobile source emissions but does not take place on the road network.
Examples of ONI activity include:

light duty passenger vehicles idling while waiting to pick up children at school or to pick up
passengers at the airport or train station,

single unit and combination trucks idling while loading or unloading cargo or making
deliveries, and

vehicles idling at drive-through restaurants.

Note that ONI does not include idling that occurs on the road, such as idling at traffic signals, stop signs,
and in traffic—these emissions are included as part of the running and crankcase running exhaust
processes on the other road types. ONI also does not include long-duration idling by long-haul
combination trucks (hoteling/extended idle), as that type of long duration idling is accounted for in other
MOVES processes.

ONI activity hours were calculated based on VMT. For each representative county, the ratio of ONI hours
to onroad VMT (on all road types) was calculated using the MOVES ONI Tool by source type, fuel type,
and month. These ratios are then multiplied by each county's total VMT (aggregated by source type, fuel
type, and month) to get hours of ONI activity.

2.3.3 MOVES Emission Factor Table Development

MOVES3 was run in emission rate mode to create emission factor tables using CB6 speciation for 2018,
for all representative counties and fuel months. The county databases used to run MOVES to develop the
emission factor tables included the state-specific control measures such as the California LEV program,
and fuels represented the year 2018. The range of temperatures run along with the average humidities
used were specific to the year 2018. The remaining settings for the CDBs are documented in the 2017
NEITSD. To create the emission factors, MOVES was run separately for each representative county and
fuel month for each temperature bin needed for the calendar year 2018. The MOVES results were post-
processed into CSV-formatted emission factor tables that can be read by SMOKE-MOVES. Additionally,
MOVES was run for all counties in Alaska, Hawaii, and Virgin Islands, and for a single representative
county in Puerto Rico, although no air quality modeling was done for these areas outside the contiguous
US.

The county databases CDBs used to run MOVES to develop the emission factor tables were those used
for the 2017 NEI and therefore included any updated data provided and accepted for the 2017 NEI
process. The 2017 NEI development included an extensive review of the various tables including speed
distributions were performed. Where state speed profiles, speed distributions, and temporal profiles data

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were not accepted from S/L submissions, those data were obtained from the CRC A-100 study. Each
county in the continental U.S. was classified according to its state, altitude (high or low), fuel region, the
presence of inspection and maintenance programs, and the mean light-duty age. A binning algorithm was
executed to identify "like counties." The result was 291 representative counties for CONUS and 38 for
Alaska, Hawaii, Puerto Rico, and the US Virgin Islands, similar to the one shown in Figure 2-3 except for
a few changes in North Carolina and Nebraska. In North Carolina there are 12 representative counties for
2018, while the figure shows 16. In Nebraska, Loop County (31115) is a separate representative county
but that is not shown in the figure.

Figure 2-3. Map of Representative Counties

Age distributions are a key input to MOVES in determining emission rates. The age distributions for 2017
were updated based on vehicle registration data obtained from the CRC A-l 15 project (CRC, 2019),
subject to reductions for older vehicles determined according to CRC A-l 15 methods but using additional
age distribution data that became available as part of the 2017 NEI submitted input data. One of the
findings of CRC project A-l 15 is that IHS data contain higher vehicle populations than state agency
analyses of the same Department of Motor Vehicles data, and the discrepancies tend to increase with
increasing vehicle age (i.e., there are more older vehicles in the IHS data).

For the 2017 NEI, EPA repeated the CRC's assessment of IHS vs. state vehicles by age, but with updated
information from the 2017 NEI and for more states. The 2017 light-duty vehicle (LDV) populations from
the CRC A-l 15 project were compared by model year to the populations submitted by state/local (S/L)

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agencies for the 2017 NEI. The comparisons by model year were used to develop adjustment factors that
remove older age LDVs from the IHS dataset. Out of 31 S/L agencies that provided age distribution and
vehicle population data for the 2017 NEI, sixteen agencies provided LDV population and age
distributions with snapshot dates of January 2017, July 2017, or 2018. The other fifteen agencies had
either unknown or older (back to 2013) data pull dates, so were compared to the 2017 IHS data. The
vehicle populations by model year were compared with IHS data for each of the sixteen agencies for
source type 21 (passenger cars) and for source type 31 plus 32 (light trucks) together. Prior to finalizing
the activity data, the S/L agency populations of source type 21 and light trucks to match IHS car and
light-duty truck splits by county so that vehicles of the same model and year were consistently classified
into MOVES source types throughout the country. The IHS population of vehicles were found to be
higher than the pooled state data by 6.5 percent for cars and 5.9 percent for light trucks.

To adjust for the additional vehicles in the IHS data, vehicle age distribution adjustment factors as one
minus the fraction of vehicles to remove from IHS to equal the state data, with two exceptions: (1) the
model year range 2006/2007 to 2017 receives no adjustment and (2) the model year 1987 receives a
capped adjustment that equals the adjustment to 1988. Table 2-14 below shows the fraction of vehicles to
keep by model year based on this analysis. The adjustments were applied to the 2017 IHS-based age
distributions from CRC project A-l 15 prior to use in this 2017 platform. In addition, the age distributions
to ensure the "tail" of the distribution corresponding to age 30 years and older vehicles did not exceed
20% of the fleet. After limiting the age distribution 30 and up bins, the age distributions were
renormalized to ensure they summed to one (1). In addition, antique license plate vehicles were removed
based on the registration summary from IHS. Nationally, the prevalence of antique plates is only 0.8
percent, but as high as 6 percent in some states (e.g., Mississippi).

Table 2-14. Fraction of IHS Vehicle Populations to Retain

Model

Cars

Light

ore-1989

0.675

0.769

1989

0.730

0.801

1990

0.732

0.839

1991

0.740

0.868

1992

0.742

0.867

1993

0.763

0.867

1994

0.787

0.842

1995

0.776

0.865

1996

0.790

0.881

1997

0.808

0.871

1998

0.819

0.870

1999

0.840

0.874

2000

0.838

0.896

2001

0.839

0.925

2002

0.864

0.921

2003

0.887

0.942

2004

0.926

0.953

2005

0.941

0.966

2006

1

0.987

2007-2017

1

1

In addition to removing the older and antique plate vehicles from the IHS data, 25 counties found to be
outliers because their fleet age was significantly younger than in typical counties. The outlier review was

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limited to LDV source types 21,31, and 32. Many rural counties have outliers for low-population source
types such as Transit Bus and Refuse Truck due to small sample sizes, but these do not have much of an
impact on the inventory overall and reflect sparse data in low-population areas and therefore do not
require correction.

The most extreme examples of LDV outliers were Light Commercial Truck age distributions where over
50 percent of the population in the entire county is 0 and 1 years old. These sorts of young fleets can
happen if the headquarters of a leasing or rental company is the owner/entity of a relatively large number
of vehicles relative to the county-wide population. While the business owner of thousands of new vehicles
may reside in a single county, the vehicles likely operate in broader areas without being registered where
they drive. To avoid creating artificial low spots of LDV emissions in these outlier counties, data for all
counties with more than 35% new vehicles were excluded from the final set of grouped age distributions
that went into the CDBs.

The 2017 NEI age distributions were then grouped using a population-weighted average of the source
type populations of each county in the representative county group, and were updated to represent the
year 2018. The resulting end-product was age distributions for each of the 13 source types in each of the
representative counties. The long-haul truck source types 53 (Single Unit) and 62 (Combination Unit) are
based on a nationwide average due to the long-haul nature of their operation.

To create the emission factors, MOVES was run separately for each representative county and fuel month
and for each temperature bin needed for calendar year 2018. The CDBs used to run MOVES include the
state-specific control measures such as the California low emission vehicle (LEV) program, except that
fuels were updated to represent calendar year 2018. In addition, the range of temperatures run along with
the average humidities used were specific to the year 2018. The MOVES results were post-processed into
CSV-formatted emission factor tables that can be read by SMOKE-MOVES.

2.3.4 Onroad California Inventory Development (onroad ca)

California uses their own emission model, EMFAC, to develop onroad emissions inventories and provides
those inventories to EPA. EMFAC uses emission inventory codes (EICs) to characterize the emission
processes instead of SCCs. The EPA and California worked together to develop a code mapping to better
match EMFAC's EICs to EPA MOVES' detailed set of SCCs that distinguish between off-network and
on-network and brake and tire wear emissions. This detail is needed for modeling but not for the NEI.
California provided emissions for 2023 as part of the 2016vl platform development. EPA interpolated
between the 2017 and 2023 emissions to calculate the 2018 onroad emissions for California. The
California inventory had CAPs only and did not have NH3 or refueling emissions. The EPA added NH3 to
the CARB inventory by using the state total NH3 from MOVES and allocating it at the county level based
on CO. Refueling emissions were projected from the 2017 NEI using county total refueling VOC from
EQUATES 2017 and the 2018 MOVES3 onroad run for California. CARB VOCs were speciated to VOC
HAPs using MOVES VOC speciation. All other HAPs (e.g., metals and PAHs) are from MOVES.

The California onroad mobile source emissions were created through a hybrid approach of combining
state-supplied annual emissions with EPA-developed SMOKE-MOVES runs. Through this approach, the
platform was able to reflect the California-developed emissions, while leveraging the more detailed SCCs
and the highly resolved spatial patterns, temporal patterns, and speciation from SMOKE-MOVES. The
basic steps involved in temporally allocating onroad emissions from California based on SMOKE-
MOVES results were:

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1)	Run CA using EPA inputs through SMOKE-MOVES to produce hourly emissions hereafter
known as "EPA estimates." These EPA estimates for CA are run in a separate sector called
"onroadca."

2)	Calculate ratios between state-supplied emissions and EPA estimates. The ratios were calculated
for each county/SCC/pollutant combination based on the California onroad emissions inventory.
Unlike in previous platforms, the California data separated off and on-network emissions and
extended idling. However, the on-network did not provide specific road types, and California's
emissions did not include information for vehicles fueled by E-85, so these differentiations were
obtained using MOVES.

3)	Create an adjustment factor file (CFPRO) that includes EPA-to-state estimate ratios.

4)	Rerun CA through SMOKE-MOVES using EPA inputs and the new adjustment factor file.

Through this process, adjusted model-ready files were created that sum to annual totals from California,
but have the temporal and spatial patterns reflecting the highly resolved meteorology and SMOKE-
MOVES. After adjusting the emissions, this sector is called "onroadcaadj " Note that in emission
summaries, the emissions from the "onroad" and "onroad ca adj" sectors are summed and designated as
the emissions for the onroad sector.

2.4 Nonroad Mobile sources (cmv, rail, nonroad)

The nonroad mobile source emission modeling sectors consist of nonroad equipment emissions (nonroad),
locomotive (rail), and CMV emissions.

2.4.1 Category 1, Category 2 Commercial Marine Vessels (cmv_c1c2)

The cmv_clc2 sector contains Category 1 and 2 CMV emissions. Category 1 and 2 vessels use diesel
fuel. All emissions in this sector are annual and at county-SCC resolution; however, in the NEI they are
provided at the sub-county level (i.e., port shape ids, where applicable) and by SCC. For more
information on CMV sources in the 2017 NEI, see Section 4.21 of the 2017 NEI TSD and the
supplemental documentation for 2017 NEI CMV.3 CI and C2 emissions that occur outside of state waters
are not assigned to states. For this modeling platform, all CMV emissions in the cmv_clc2 sector were
treated as hourly gridded point sources with stack parameters that should result in them being placed in
layer 1. The C1C2 CMV emissions were projected from 2017 to 2018 by applying an adjustment factor of
1.012 to the 2017 NEI emissions values.

Sulfur dioxide (S02) emissions reflect rules that reduced sulfur emissions for CMV that took effect in the
year 2015. The cmv_clc2 inventory sector contains small to medium-size engine CMV emissions.
Category 1 and Category 2 (C1C2) marine diesel engines typically range in size from about 700 to 11,000
hp. These engines are used to provide propulsion power on many kinds of vessels including tugboats,
towboats, supply vessels, fishing vessels, and other commercial vessels in and around ports. They are also
used as stand-alone generators for auxiliary electrical power on many types of vessels. Category 1
represents engines up to 7 liters per cylinder displacement. Category 2 includes engines from 7 to 30 liters
per cylinder.

The cmv_clc2 inventory sector contains sources that traverse state and federal waters along with
emissions from surrounding areas of Canada, Mexico, and international waters. The cmv_clc2 sources

3 https://www.epa.gov/sites/default/files/2019-l 1/cmv methodology documentation.zip.

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are modeled as point sources but using plume rise parameters that cause the emissions to be released in
the ground layer of the air quality model.

The cmv_clc2 sources within state waters are identified in the inventory with the Federal Information
Processing Standard (FIPS) county code for the state and county in which the vessel is registered. The
cmv_clc2 sources that operate outside of state waters but within the Emissions Control Area (ECA) are
encoded with a state FIPS code of 85. The ECA areas include parts of the Gulf of Mexico, and parts of the
Atlantic and Pacific coasts. The cmv_clc2 sources in the base year inventory are categorized as operating
either in-port or underway and as main and auxiliary engines are encoded using the SCCs listed in Table
2-13.

Table 2-15. SCCs for cmv clc2 sector

sec

Tier 1 Description

Tier 2 Description

Tier 3 Description

Tier 4 Description

2280002101

C1/C2

Diesel

Port

Main

2280002102

C1/C2

Diesel

Port

Auxiliary

2280002201

C1/C2

Diesel

Underway

Main

2280002202

C1/C2

Diesel

Underway

Auxiliary

Category 1 and 2 CMV emissions were developed for the 2017 NEI,4 The 2017 NEI emissions were
developed based signals from Automated Identification System (AIS) transmitters. AIS is a tracking
system used by vessels to enhance navigation and avoid collision with other AIS transmitting vessels. The
USEPA Office of Transportation and Air Quality received AIS data from the U.S. Coast Guard (USCG)
in order to quantify all ship activity which occurred between January 1 and December 31, 2017. The
provided AIS data extends beyond 200 nautical miles from the U.S. coast (Figure 2-4). This boundary is
roughly equivalent to the border of the U.S Exclusive Economic Zone and the North American ECA,
although some non-ECA activity are captured as well.

The AIS data were compiled into five-minute intervals by the USCG, providing a reasonably refined
assessment of a vessel's movement. For example, using a five-minute average, a vessel traveling at 25
knots would be captured every two nautical miles that the vessel travels. For slower moving vessels, the
distance between transmissions would be less. The ability to track vessel movements through AIS data
and link them to attribute data, has allowed for the development of an inventory of very accurate emission
estimates with excellent resolution in time and space. These AIS data were used to define the locations of
individual vessel movements, estimate hours of operation, and quantify propulsion engine loads. The
compiled AIS data also included the vessel's International Marine Organization (IMO) number and
Maritime Mobile Service Identifier (MMSI); which allowed each vessel to be matched to their
characteristics obtained from the Clarksons ship registry (Clarksons, 2018).

4 Category 1 and 2 Commercial Marine Vessel 2017 Emissions Inventory (ERG, 2019b).

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Figure 2-4. 2017NEI geographical extent of marine emissions (solid) and the U.S. ECA (dashed)

The engine bore and stroke data were used to calculate cylinder volume. Any vessel with a calculated
cylinder volume greater than 30 liters was incorporated into the USEPA's Category 3 Commercial Marine
Vessel (C3CMV) model. The remaining records were assumed to represent Category 1 and 2 (C1C2) or
non-ship activity. The C1C2 AIS data were quality assured including the removal of duplicate messages,
signals from pleasure craft, and signals that were not from CMV vessels (e.g., buoys, helicopters, and
vessels that are not self-propelled). Following this, there were 422 million records remaining.

The emissions were calculated for each time interval between consecutive AIS messages for each vessel
and allocated to the location of the message following to the interval. Emissions were calculated
according to Equation 2-1.

Emissions interval = Time (hr interval* Power(kW) EF(g/kWh) LLAF	Equation 2-1

Power is calculated for the propulsive (main), auxiliary, and auxiliary boiler engines for each interval and
emission factor (EF) reflects the assigned emission factors for each engine, as described below. LLAF
represents the low load adjustment factor, a unit I ess factor which reflects increasing propulsive emissions
during low load operations. Time indicates the activity duration time between consecutive intervals.

Next, vessels were identified in order to determine their vessel type, and thus their vessel group, power
rating, and engine tier information which are required for the emissions calculations. See the 2017 NEI
documentation for more details on this process. Following the identification, 108 different vessel types
were matched to the C1C2 vessels. Vessel attribute data was not available for all these vessel types, so the
vessel types were aggregated into 13 different vessel groups for which surrogate data were available as
shown in Table 2-16. In total, 11,302 vessels were directly identified by their ship and cargo number. The
remaining group of miscellaneous ships represent 13 percent of the AIS vessels (excluding recreational
vessels) for which a specific vessel type could not be assigned.

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Table 2-16. Vessel groups in the cmv_clc2 sector

Vessel Group

NEI Area Ship Count

Bulk Carrier

37

Commercial Fishing

1,147

Container Ship

7

Ferry Excursion

441

General Cargo

1,498

Government

1,338

Miscellaneous

1,475

Offshore support

1,149

Reefer

13

Ro

26

Tanker

100

Tug

3,994

Work Boat

77

Total in Inventory:

11.302

As shown in Equation 2-1, power is an important component of the emissions computation. Vessel-
specific installed propulsive power ratings and service speeds were pulled from Clarksons ship registry
and adopted from the Global Fishing Watch (GFW) dataset when available. However, there is limited
vessel specific attribute data for most of the C1C2 fleet. This necessitated the use of surrogate engine
power and load factors, which were computed for each vessel group. In addition to the power required by
propulsive engines, power needs for auxiliary engines were also computed for each vessel group.
Emissions from main and auxiliary engines are inventoried with different SCCs as shown in Table 2-15.

The final components of the emissions computation equation are the emission factors and the low load
adjustment factor. The emission factors used in this inventory take into consideration the EPA's marine
vessel fuel regulations as well as exhaust standards that are based on the year that the vessel was
manufactured to determine the appropriate regulatory tier. Emission factors in g/kWhr by tier for NOx,
PMio, PM2.5, CO, CO2, SO2 and VOC were developed using Tables 3-7 through 3-10 in USEPA's (2008)
Regulatory Impact Analysis on engines less than 30 liters per cylinder. To compile these emissions
factors, population-weighted average emission factors were calculated per tier based on C1C2 population
distributions grouped by engine displacement. Boiler emission factors were obtained from an earlier
Swedish Environmental Protection Agency study (Swedish EPA, 2004). If the year of manufacture was
unknown then it was assumed that the vessel was Tier 0, such that actual emissions may be less than those
estimated in this inventory. Without more specific data, the magnitude of this emissions difference cannot
be estimated.

Propulsive emissions from low-load operations were adjusted to account for elevated emission rates
associated with activities outside the engines' optimal operating range. The emission factor adjustments
were applied by load and pollutant, based on the data compiled for the Port Everglades 2015 Emission

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Inventory.5 Hazardous air pollutants and ammonia were added to the inventory according to multiplicative
factors applied either to VOC or PM2.5.

For more information on the emission computations for 2017, see the supporting documentation for the
2017 NEI C1C2 CMV emissions. The emissions from the 2017 NEI were adjusted to represent 2018 in
the cmv_clc2 sector by applying a factor of 1.012 to all pollutants (based on EIA fuel use data). For
consistency, the same methods were used for California, Canadian, and other non-U.S. emissions. The
2017 emissions were mapped to 2018 dates so that the activity occurred on the same day of the week in
the same sequential week of the year in both years. Holidays and days of the week were mapped from the
dates in 2017 to the corresponding dates in 2018 to preserve weekday-weekend and holiday-centered
fluctuations in emissions in each of the years. Individual vessels that released emissions within the same
grid cell for over 400 hours were flagged as hoteling. The emissions from the hoteling vessels were scaled
to the 400-hour cap. Both the annual and hourly inventory files were projected to 2018 using the same
projection factor of 1.012.

2.4.2 Category 3 Commercial Marine Vessels (cmv_c3)

This sector contains large engine CMV emissions. Category 3 (C3) marine diesel engines are those at or
above 30 liters per cylinder, typically these are the largest engines rated at 3,000 to 100,000 hp. C3
engines are typically used for propulsion on ocean-going vessels including container ships, oil tankers,
bulk carriers, and cruise ships. Emissions control technologies for C3 CMV sources are limited due to the
nature of the residual fuel used by these vessels.6 The cmv_c3 sector contains sources that traverse state
and federal waters; along with sources in waters not covered by the NEI in surrounding areas of Canada,
Mexico, and international waters. For more information on CMV sources in the 2017 NEI, see Section
4.21 of the 2017 NEI TSD and the supplemental documentation for 2017 NEI CMV.7

The cmv_c3 sources that operate outside of state waters but within the federal Emissions Control Area
(ECA) are encoded with a FIPS state code of 85, with the "county code" digits representing broad regions
such as the Atlantic, Gulf of Mexico, and Pacific. The ECA areas include parts of the Gulf of Mexico, and
parts of the Atlantic and Pacific coasts. CMV C3 sources around Puerto Rico, Hawaii and Alaska, which
are outside the ECA areas, are included in the 2018 inventory but are in separate files from the emissions
around the continental United States (CONUS). The cmv_c3 sources in the 2018 inventory are
categorized as operating either in-port or underway and are encoded using the SCCs listed in Table 2-17.
and distinguish between diesel and residual fuel, in port areas versus underway, and main and auxiliary
engines. In addition to C3 sources in state and federal waters, the cmv_c3 sector includes emissions in
waters not covered by the NEI (FIPS = 98) and taken from the "ECA-IMO-based" C3 CMV inventory.8

5	USEPA. EPA and Port Everglades Partnership: Emission Inventories and Reduction Strategies. US Environmental
Protection Agency, Office of Transportation and Air Quality, June 2018.
https://nepis.epa.gov/Exe/ZvPDF.cgi?Dockev=P100UKV8.pdf.

6	https://www.epa.gov/regulations-emissions-vehicles-and-engines/regulations-emissions-marine-vessels.

7	https://www.epa.gov/sites/default/files/2019-l 1/cmv methodology documentation.zip.

8	https://www.epa.gOv/sites/production/files/2017-08/documents/2014v7.0 2014 emismod tsdvl.pdf.

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The ECA-IMO inventory is also used for allocating the FlPS-level emissions to geographic locations for
regions within the domain not covered by the AIS selection boxes as described in the next section.

Table 2-17. SCCs for cmv c3 sector

see

Tier 1 Description

Tier 2 Description

Tier 3 Description

Tier 4 Deseriplinn

2280002103

C3

Diesel

Port

Main

2280002104

C3

Diesel

Port

Auxiliary

2280002203

C3

Diesel

Underway

Main

2280002204

C3

Diesel

Underway

Auxiliary

2280003103

C3

Residual

Port

Main

2280003104

C3

Residual

Port

Auxiliary

2280003203

C3

Residual

Underway

Main

2280003204

C3

Residual

Underway

Auxiliary

Prior to creation of the 2017 NEI, the EPA received Automated Identification System (AIS) data from
United States Coast Guard (USCG) to quantify all ship activity which occurred between January 1 and
December 31, 2017. The International Maritime Organization's (IMO's) International Convention for the
Safety of Life at Sea (SOLAS) requires AIS to be fitted aboard all international voyaging ships with gross
tonnage of 300 or more, and all passenger ships regardless of size.9 In addition, the USCG has mandated
that all commercial marine vessels continuously transmit AIS signals while transiting U.S. navigable
waters. As the vast majority of C3 vessels meet these requirements, any omitted from the inventory due to
lack of AIS adoption are deemed to have a negligible impact on national C3 emissions estimates. The
activity described by this inventory reflects ship operations within 200 nautical miles of the official U.S.
baseline. This boundary is roughly equivalent to the border of the U.S Exclusive Economic Zone and the
North American ECA, although some non-ECA activity is captured as well (Figure 2-4).

The 2017 NEI CMV emissions were computed based on the AIS data from the USCG for the year of
2017. The AIS data were coupled with ship registry data that contained engine parameters, vessel power
parameters, and other factors such as tonnage and year of manufacture which helped to separate the C3
vessels from the C1C2 vessels. Where specific ship parameters were not available, they were gap-filled.
The types of vessels that remain in the C3 data set include bulk carrier, chemical tanker, liquified gas
tanker, oil tanker, other tanker, container ship, cruise, ferry, general cargo, fishing, refrigerated vessel,
roll-on/roll-off, tug, and yacht.

Prior to their use, the AIS data were reviewed - data deemed to be erroneous were removed, and data
found to be at intervals greater than 5 minutes were interpolated to ensure that each ship had data every
five minutes. The five-minute average data provide a reasonably refined assessment of a vessel's
movement. For example, using a five-minute average, a vessel traveling at 25 knots would be captured
every two nautical miles that the vessel travels. For slower moving vessels, the distance between
transmissions would be less.

9 International Maritime Organization (IMO) Resolution MSC.99(73) adopted December 12th. 2000 and entered into force July
1st, 2002; as amended by SOLAS Resolution CONF.5/32 adopted December 13th, 2002.

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The emissions were calculated for each C3 vessel in the dataset for each 5-minute time range and
allocated to the location of the message following to the interval. Emissions were calculated according to
Equation 2-2.

Emissionsintervai = Time (hr)intervaix Power(kW)xEF(g/kWh)xLLAF	Equation 2-2

Power is calculated for the propulsive (main), auxiliary, and auxiliary boiler engines for each interval and
emission factor (EF) reflects the assigned emission factors for each engine, as described below. LLAF
represents the low load adjustment factor, a unitless factor which reflects increasing propulsive emissions
during low load operations. Time indicates the activity duration time between consecutive intervals.

Emissions were computed according to a computed power need (kW) multiplied by the time (hr) and by
an engine-specific emission factor (g/kWh) and finally by a low load adjustment factor that reflects
increasing propulsive emissions during low load operations.

The resulting emissions were available at 5-minute intervals. Code was developed to aggregate these
emissions to modeling grid cells and up to hourly levels so that the emissions data could be input to
SMOKE for emissions modeling with SMOKE. Within SMOKE, the data were speciated into the
pollutants needed by the air quality model,10 but since the data were already in the form of point sources
at the center of each grid cell, and they were already hourly, no other processing was needed within
SMOKE. SMOKE requires an annual inventory file to go along with the hourly data, so those files were
also generated for each year.

On January 1st, 2015, the ECA initiated a fuel sulfur standard which regulated large marine vessels to use
fuel with 1,000 ppm sulfur or less. These standards are reflected in the cmv_c3 inventories.

There were some areas needed for modeling that the AIS request boxes did not cover (see Figure 2-4).
These include a portion of the St. Lawrence Seaway transit to the Great Lakes, a small portion of the
Pacific Ocean far offshore of Washington State, portions of the southern Pacific Ocean around off the
coast of Mexico, and the southern portion of the Gulf of Mexico that is within the 36-km domain used for
air quality modeling. In addition, a determination had to be made regarding whether to use the existing
Canadian CMV inventory or the more detailed AlS-based inventory. The AlS-based inventory was used
in the areas for which data were available, and the areas not covered were gap-filled with inventory data
from the 2016beta platform, which included data from ECCC and the 2011 ECA-IMO C3 inventory.

For the gap-filled areas not covered by AIS selected data areas or the ECCC inventory, the 2016 nonpoint
C3 inventory provided by ECCC was converted to a point inventory to support plume rise calculations for
C3 vessels. The nonpoint emissions were allocated to point sources using a multi-step allocation process
because not all of the inventory components had a complete set of county-SCC combinations. In the first
step, the county-SCC sources from the nonpoint file were matched to the county-SCC points in the 2011

10 Ammonia (NH3) was also added by SMOKE in the speciation step.

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ECA-IMO C3 inventory. The ECA-IMO inventory contains multiple point locations for each county -
SCC. The nonpoint emissions were allocated to those points using the PM2.5 emissions at each point as a
weighting factor.

For cmv_c3 underway emissions without a matching FIPS in the ECA-IMO inventory were allocated
using the 12 km 2014 offshore shipping activity spatial surrogate (surrogate code 806). Each county with
underway emissions in the area inventory was allocated to the centroids of the cells associated with the
respective county in the surrogate. The emissions were allocated using the weighting factors in the
surrogate.

The resulting point emissions centered on each grid cell were converted to an annual point 2010 flat file
format (FF10). A set of standard stack parameters were assigned to each release point in the cmv_c3
inventory. The assigned stack height was 65.62 ft, the stack diameter was 2.625 ft, the stack temperature
was 539.6 °F, and the velocity was 82.02 ft/s. Emissions were computed for each grid cell needed for
modeling.

Adjustment of the 2017 NEI CMV C3 to 2018

Both the annual and hourly Category 3 (C3) CMV emissions were projected from 2017 to 2018 using
factors derived from an EPA report on projected bunker fuel demand (See Table 2-18). The report
projects bunker fuel consumption by region out to the year 2030. Bunker fuel usage was used as a
surrogate for marine vessel activity. Factors based on the report were used for all pollutants except NOx.
Growth factors for NOx emissions were handled separately to account for the phase in of Tier 3 vessel
engines. The projection factors are shown in Table 2-18.

Table 2-18. Projection Factors for 2017 to 2018 for Category 3 Vessels

Region

NOx

All other pollutants

US East Coast

0.9869

1.0346

US South Pacific

0.9494

1.0153

US North Pacific

0.9926

1.0246

US Gulf of Mexico

0.9910

1.0253

US Great Lakes

1.0051

1.0173

The cmv_c3 projection factors were pollutant-specific and region-specific. Most states are mapped to a
single region with a few exceptions. Pennsylvania and New York were split between the East Coast and
Great Lakes, Florida was split between the Gulf Coast and East Coast, and Alaska was split between
Alaska East and Alaska West. The non-federal factors listed in this table were applied to sources outside
of U.S. federal waters (FIPS 98). Volatile Organic Compound (VOC) Hazardous Air Pollutant (HAP)
emissions were projected using the VOC factors. NH3 emissions were computed by multiplying PM2.5
by 0.019247.

2.4.3 Railway Locomotives (rail)

The rail sector includes all locomotives in the NEI nonpoint data category including line haul locomotives
on Class 1, 2, and 3 railroads along with emissions from commuter rail lines and Amtrak. The rail sector

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excludes railway maintenance locomotives and point source yard locomotives. Railway maintenance
emissions are included in the nonroad sector. The point source yard locomotives are included in the
ptnonipm sector. Typically in the NEI, yard locomotive emissions are split between the nonpoint and
point categories, but for this study, all yard locomotive emissions are represented as point sources and
included in the ptnonipm sector.

This study uses the 2017 rail inventory developed for the 2017 NEI by the Lake Michigan Air Directors
Consortium (LADCO) and the State of Illinois with support from various other states. Class I railroad
emissions are based on confidential link-level line-haul activity GIS data layer maintained by the Federal
Railroad Administration (FRA). In addition, the Association of American Railroads (AAR) provided
national emission tier fleet mix information. Class II and III railroad emissions are based on a
comprehensive nationwide GIS database of locations where short line and regional railroads operate.
Passenger rail (Amtrak) emissions follow a similar procedure as Class II and III, except using a database
of Amtrak rail lines. Yard locomotive emissions are based on a combination of yard data provided by
individual rail companies, and by using Google Earth and other tools to identify rail yard locations for rail
companies which did not provide yard data. Information on specific yards were combined with fuel use
data and emission factors to create an emissions inventory for rail yards. Pollutant-specific factors were
applied on top of the activity-based changes for the Class I rail. The inventory SCCs are shown in Table
2-19. More detailed information on the development of the 2017 NEI rail inventory for this study is
available in the 2017 NEI TSD. The 2017 NEI rail inventory was projected to 2018 using activity-based
factors shown in Table 2-20. This activity-based factor was based on AEO fuel data.

Table 2-19. SCCs for the rail sector

sec

Sector

Description: Mobile Sources prefix for all

2285002006

Rail

Railroad Equipment; Diesel; Line Haul Locomotives: Class I Operations

2285002007

Rail

Railroad Equipment; Diesel; Line Haul Locomotives: Class II / III Operations

2285002008

Rail

Railroad Equipment; Diesel; Line Haul Locomotives: Passenger Trains
(Amtrak)

2285002009

Rail

Railroad Equipment; Diesel; Line Haul Locomotives: Commuter Lines

2285002010

Rail

Railroad Equipment; Diesel; Yard Locomotives (nonpoint)

28500201

Rail

Railroad Equipment; Diesel; Yard Locomotives (point)

Table 2-20. 2017-to-2018 projection factors for the rail sector

NOx

PM

VO(

Other pollutants

+2.44%

-3.29%

-2.95%

+6.63%

Class I Line-haul Methodology

In 2008, air quality planners in the eastern US formed the Eastern Technical Advisory Committee
(ERTAC) for solving persistent emissions inventory issues. This work is the fourth inventory created by
the ERTAC rail group. For the 2017 inventory, the Class I railroads granted ERTAC Rail permission to
use the confidential link-level line-haul activity GIS data layer maintained by the Federal Railroad
Administration (FRA) for 2016. In addition, the Association of American Railroads (AAR) provided
national emission tier fleet mix information. This allowed ERTAC Rail to calculate weighted emission

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factors for each pollutant based on the percentage of the Class I line-haul locomotives in each USEPA
Tier level category. These two datasets, along with 2017 Class I line-haul fuel use data reported to the
Surface Transportation Board were used to create a link-level Class I emissions inventory, based on a
methodology recommended by Sierra Research. Rail Fuel Consumption Index (RFCI) is a measure of fuel
use per ton mile of freight. This link-level inventory is nationwide in extent, but it can be aggregated at
either the state or county level.

Annual default emission factors for locomotives based on operating patterns ("duty cycles") and the
estimated nationwide fleet mixes for both switcher and line-haul locomotives are available. However,

Tier level fleet mixes vary significantly between the Class I and Class II/III railroads. As can be seen in
Figure 2-5 and Figure 2-6. Class I railroad activity is highly regionalized in nature and is subject to
variations in terrain across the country which can have a significant impact on fuel efficiency and overall
fuel consumption.

Figure 2-5. 2017 US Railroad Traffic Density in Millions of Gross Tons per Route Mile (MGT)

Source: Federal Railroad Administration - June 2018

Traffic Density

0.02 - 4.99 MGT
5.00 - 9.99 MGT

	 10.00 -19.99 MGT

20.00 - 39.99 MGT
40.00 - 59.99 MGT

	 60.00 - 99.99 MGT

>= 100.00 MGT

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Figure 2-6. Class I Railroads in the United States

	 NS

UP

Source: Federal Railroad Administration - December 2016

Class II and III Methodology

There are approximately 560 Class II and III Railroads operating in the United States, most of which are
members of the American Short Line and Regional Railroad Associ ation (ASLRRA). While there is a lot
of information about individual Class II and III railroads available online, a significant amount of effort
would be required to convert this data into a usable format for the creation of emission inventories. In
addition, the Class II and III rail sector has been in a constant state of flux ever since the railroad industry
was deregulated under the Staggers Act in 1980. Some states have conducted independent surveys of their
Class II and III railroads and produced emission estimates, but no national level emissions inventory
existed for this sector of the railroad industry prior to ERTAC Rail's work for the 2008 NEI.

Class II and III railroad activities account for nearly 4 percent of the total locomotive fuel use in the
combined ERTAC Rail emission inventories and for approximately 35 percent of the industry's national
freight rail track mileage. These railroads are widely dispersed across the country and often utilize older,
higher emitting locomotives than their Class I counterparts Class II and III railroads provide
transportation services to a wide range of industries. Individual railroads in this sector range from small
switching operations serving a single industrial plant to large regional railroads that operate hundreds of
miles of track. Figure 2-7 shows the distribution of Class II and III railroads and commuter railroads
across the country.

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Figure 2-7. Class II and III Railroads in the United States

P Haircufci Ad»un vr»i uyn -J une 2018

Commuter Railroads

Commuter Rail Methodology

Commuter rail emissions were calculated in the same way as the Class II and III railroads. The primary
difference is that the fuel use estimates were based on data collected by the Federal Transit
Administration (FTA) for the National Transit Database. For the 2017 NEI, 2016 fuel use was estimated
for each of the commuter railroads by multiplying the fuel and lube cost total by 0.95, then dividing the
result by Metra's average diesel fuel cost of $1,93/gallon. These fuel use estimates were replaced with
reported fuel use statistics for MARC (Maryland), MBTA (Massachusetts), Metra (Illinois), and NJT
(New Jersey). The commuter railroads were separated from the Class II and III railroads so that the
appropriate SCC codes could be entered into the emissions calculation sheet.

Intercity Passenger Methodology (Amtrak)

2016 and 2017 marked the first times that a nationwide intercity passenger rail emissions inventory was
created for Amtrak. The calculation methodology mimics that used for the Class II and III and commuter
railroads with a few modifications. Since link-level activity data for Amtrak was unavailable, the default
assumption was made to evenly distribute Amtrak's 2016 reported fuel use across all of it diesel-powered
route-miles shown in Figure 2-8. Participating states were instructed that they could alter the fuel use
distribution within their jurisdictions by analyzing Amtrak's 2016 national timetable and calculating
passenger train-miles for each affected route. Illinois and Connecticut chose to do this and were able to
derive activity-based fuel use numbers for their states based on Amtrak's 2016 reported average fuel use

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of 2.2 gallons per passenger train-mile. In addition, Connecticut provided supplemental data for selected
counties in Massachusetts, New Hampshire, and Vermont. Amtrak also submitted company-specific fleet
mix information and company-specific weighted emission factors were derived. Amtrak's emission rates
were 25% lower than the default Class II and III and commuter railroad emission rate.

Figure 2-8. Amtrak Routes with Diesel-powered Passenger Trains

Scurc* FdkijJ R**wd	- 1m »I*

Other Data Sources

The California Air Resources Board (CARB) provided rail inventories for inclusion in the 2017 NEI.
CARB's rail inventories were used in California, in place of the national dataset described above. For rail
yards, the national point source rail yard dataset was used to allocate CARB-submitted rail yard emissions
to point sources where possible. That is, for each California county with at least one rail yard in the
national dataset, the emissions in the national rail yard dataset were adjusted so that county total rail yard
emissions matched the CARB dataset. In other words, county total rail yard emissions from CARB are
used, but the locations of rail yards are based on the national methodology. There are three counties with
CARB-submitted rail yard emissions, but no rail yard locations in the national dataset; for those counties,
the rail yard emissions were included in the rail sector using SCC 2285002010.

2.4.4 Nonroad Mobile Equipment (nonroad)

The mobile nonroad equipment sector includes all mobile source emissions that do not operate on roads,
excluding commercial marine vehicles, railways, and aircraft. Types of nonroad equipment include
recreational off-road vehicles, pleasure craft, and construction, agricultural, mining, and lawn and garden
equipment. Nonroad equipment emissions were computed by running MOVES3 which incorporates the
NONROAD model. MOVES3 incorporated updated nonroad engine population growth rates, nonroad
Tier 4 engine emission rates, and sulfur levels of nonroad diesel fuels. MOVES provides a complete set of
HAPs and incorporates updated nonroad emission factors for HAPs. MOVES3 was used for all states

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other than California, which uses their own model, and the Texas Commission on Environmental Quality
(TCEQ), which provided their own emissions. California nonroad emissions were provided by the
California Air Resources Board (CARB) for the 2017 NEI. The 2018 California nonroad emissions were
interpolated from the 2017 NEI and a 2023 projection from the 2016vl modeling platform, with HAP
augmentation. For Texas, the EPA interpolated to 2018 between data provided for 2017 and 2020 and
applied HAP augmentation.

MOVES creates a monthly emissions inventory for criteria air pollutants (CAPs) and a full set of HAPs,
plus additional pollutants such as NONHAPTOG and ETHANOL, which are not part of the NEI but are
used for speciation. MOVES provides estimates of NONHAPTOG along with the speciation profile code
for the NONHAPTOG emission source. This was accomplished by using NHTOG#### as the pollutant
code in the Flat File 2010 (FF10) inventory file that can be read into SMOKE, where #### is a speciation
profile code. For California and Texas, NHTOG####-VOC and HAP-VOC ratios from MOVES-based
emissions were applied to VOC emissions so that VOC emissions can be speciated consistently with other
states.

MOVES also provides estimates of PM2.5 by speciation profile code for the PM2.5 emission source, using
PM25_#### as the pollutant code in the FF10 inventory file, where #### is a speciation profile code. To
facilitate calculation of PMC within SMOKE, and to help create emissions summaries, an additional
pollutant representing total PM2.5 called PM25TOTAL was added to the inventory. As with VOC,
PM25_####-PM25TOTAL ratios were calculated and applied to PM2.5 emissions in California and Texas
so that PM2.5 emissions in California and Texas can be speciated consistently with other states.

MOVES3 outputs emissions data in county-specific databases, and a post-processing script converts the
data into FF10 format. Additional post-processing steps were performed as follows:

•	County-specific FFlOs were combined into a single FF10 file.

•	Emissions were aggregated from the more detailed SCCs modeled in MOVES to the SCCs
available as part of the 2017 NEI.

•	To reduce the size of the inventory, HAPs that are not needed for air quality modeling, such as
dioxins and furans, were removed from the inventory.

•	To reduce the size of the inventory further, all emissions for sources (identified by county/SCC)
for which total CAP emissions are less than 1*10"10 were removed from the inventory. The
MOVES model attributes a very tiny amount of emissions to sources that are actually zero, for
example, snowmobile emissions in Florida. Removing these sources from the inventory reduces
the total size of the inventory by about 7%.

•	Gas and particulate components of HAPs that come out of MOVES separately, such as
naphthalene, were combined.

•	VOC was renamed VOC INV so that SMOKE does not speciate both VOC and NONHAPTOG,
which would result in a double count.

•	PM25TOTAL, referenced above, was created at this stage of the process to facilitate the
calculation of PMC within SMOKE and for the development of emissions summaries.

•	Emissions for airport ground support vehicles (SCCs ending in -8005), and oil field equipment
(SCCs ending in -10010), were removed from the inventory at this stage, to prevent a double
count with the airports and np oilgas sectors, respectively.

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• California and Texas emissions from MOVES were deleted and replaced with CARB- and TCEQ-
supplied emissions, respectively.

National Updates: Agricultural and Construction Equipment Allocation

The methodology for developing agricultural equipment allocation data for the 2016vl platform was
developed by the North Carolina Department of Environmental Quality (NCDEQ). EPA updated the
construction equipment allocation data used in MOVES for the 2016vl platform ad those updates are
retained for use in this platform. Updated nrsurrogate, nrstate surrogate, and nrbaseyearequippopulation
tables that implement these updates, along with instructions for utilizing these tables in MOVES runs, are
available for download from EPA's ftp site: https://gaftp.epa.gov/air/emismod/2016/vl/reports/nonroad/).
Note that these updates are not included in M0VES3.

More information on the development of the updates to agricultural and construction equipment
allocations is available in Section 2.4.4 of the 2016v3 platform TSD (EPA, 2023a).

Emissions Inside California and Texas

California nonroad emissions were provided by CARB for 2017NEI, and for several years including 2016
and 2023 as part of the 2016 version 1 modeling platform. The 2017 and 2023 datasets provided by
CARB were used to estimate California nonroad emissions for 2018. Specifically, county-level trends by
pollutant were calculated for the six year period from 2017 to 2023, converted (interpolated) to a one year
trend, and then applied to the 2017 emissions to estimate 2018. Trends based on county totals were used
instead of more specific trends (e.g. by SCC) because of possible differences in SCC delineations between
the different CARB datasets.

All California nonroad inventories are annual, with monthly temporalization applied in SMOKE.
Emissions for oil field equipment (SCCs ending in -10010) were removed from the California inventory
in order to prevent a double count with the np oilgas sector. VOC and PM2.5 emissions were allocated to
speciation profiles, and VOC HAPs were created, using MOVES data in California. For example, ratios
of VOC (PM2.5) by speciation profile to total VOC (PM2.5), and ratios of VOC HAPs to total VOC, were
calculated by county and SCC from the MOVES run in California, and then applied CARB-provided
VOC (PM2.5) in the inventory so that California nonroad emissions could be speciated consistently with
the rest of the country.

Texas nonroad emissions were provided by TCEQ for years 2017 and 2020, and then interpolated to 2018
for each county, SCC, and pollutant. The Texas nonroad inventories are seasonal (summer, fall, winter,
spring), split to monthly by dividing the seasonal total by three for each month. As in California, VOC
and PM2.5 emissions were allocated to speciation profiles, and VOC HAPs were created, using MOVES
data in Texas.

Nonroad Updates from State Comments

The 2016 Nonroad Collaborative workgroup received a small number of comments on the 2016beta
inventory (EPA and NEIC, 2019), all of which were addressed and implemented in the 2017 NEI nonroad
inventory and the 2018 inventory used for this study:

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•	Georgia Department of Natural Resources: utilize updated geographic allocation factors
(nr state surrogate table) for the Commercial, Lawn & Garden (commercial, public, and
residential), Logging, Manufacturing, Golf Carts, Recreational, Railroad Maintenance Equipment
and A/C/Refrigeration sectors, using data from the U.S. Census Bureau and U.S. Forest Service.

•	Lake Michigan Air Directors Consortium (LADCO): update seasonal allocation of agricultural
equipment activity (nrmonthallocation table) for Illinois, Indiana, Iowa, Michigan, Minnesota,
Missouri, Ohio, and Wisconsin.

•	Texas Commission on Environmental Quality: replace MOVES nonroad emissions for Texas
with emissions calculated with TCEQ's TexN2 model.

•	Alaska Department of Environmental Conservation: remove emissions as calculated by
MOVES for several equipment sector-county/census areas combinations in Alaska, due to an
absence of nonroad activity (see Table 2-21). Note that this is only relevant for the 36km grid
used in this study because Alaska does not overlap the 12km grid.

Table 2-21. Alaska counties/census areas for which specific nonroad emissions were removed

N oil road

Kquipmenl

Sector

Coiinlies/Censiis Areas (KIPS) for which equipment sector emissions are
removed

Agricultural

Aleutians East (02013), Aleutians West (02016), Bethel Census Area (02050),
Bristol Bay Borough (02060), Dillingham Census Area (02070), Haines
Borough (02100), Hoonah-Angoon Census Area (02105), Ketchikan Gateway
(02130), Kodiak Island Borough (02150), Lake and Peninsula (02164), Nome
(02180), North Slope Borough (02185), Northwest Arctic (02188), Petersburg
Borough (02195), Pr of Wales-Hyder Census Area (02198), Sitka Borough
(02220), Skagway Borough (02230), Valdez-Cordova Census Area (02261),
Wade Hampton Census Area (02270), Wrangell City + Borough (02275),
Yakutat City + Borough (02282), Yukon-Koyukuk Census Area (02290)

Logging

Aleutians East (02013), Aleutians West (02016), Nome (02180), North Slope
Borough (02185), Northwest Arctic (02188), Wade Hampton Census Area
(02270)

Railway
Maintenance

Aleutians East (02013), Aleutians West (02016), Bethel Census Area (02050),
Bristol Bay Borough (02060), Dillingham Census Area (02070), Haines
Borough (02100), Hoonah-Angoon Census Area (02105), Juneau City +
Borough (02110), Ketchikan Gateway (02130), Kodiak Island Borough (02150),
Lake and Peninsula (02164), Nome (02180), ), North Slope Borough (02185),
Northwest Arctic (02188), Petersburg Borough (02195), Pr of Wales-Hyder
Census Area (02198), Sitka Borough (02220), Southeast Fairbanks (02240),
Wade Hampton Census Area (02270), Wrangell City + Borough (02275),
Yakutat City + Borough (02282), Yukon-Koyukuk Census Area (02290)

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2.5 Fires (ptfire-wild, ptfire-rx, ptagfire)

Multiple types of fires are represented in the modeling platform. These include wild and prescribed fires
that are grouped into the ptfire-wild and ptfire-rx sectors, respectively, and agricultural fires that comprise
the ptagfire sector. All ptfire and ptagfire fires are in the United States. Fires outside of the United States
are described in the ptfire othna sector later in this document.

2.5.1 Wild and Prescribed Fires (ptfire-rx, ptfire-wild)

Wildfire and prescribed burning emissions are contained in the ptfire-wild and ptfire-rx sectors, respectively. The
ptfire sector has emissions provided at geographic coordinates (point locations) and has daily emissions values. The
ptfire sector excludes agricultural burning and other open burning sources that are included in the ptagfire sector.
Emissions are day-specific and include satellite-derived latitude/longitude of the fire's origin and other parameters
associated with the emissions such as acres burned and fuel load, which allow estimation of plume rise.

The SCCs used for the ptfire-rx and ptfire-wild sources are shown in Table 2-22. The ptfire-rx and ptfire-
wild inventories include separate SCCs for the flaming and smoldering combustion phases for wildfire
and prescribed burns. Note that prescribed grassland fires for the Flint Hills in Kansas have their own
SCC (2811021000) in the inventory. These wild grassland fires were assigned the standard wildfire SCCs
shown in Table 2-22.

Table 2-22. SCCs included in the ptfire sector

SCC

Description

2810001001

Forest Wildfires; Smoldering; Residual smoldering only (includes grassland wildfires)

2810001002

Forest Wildfires; Flaming (includes grassland wildfires)

2811015001

Prescribed Forest Burning; Smoldering; Residual smoldering only

2811015002

Prescribed Forest Burning; Flaming

2811020002

Prescribed Rangeland Burning

2811021000

Prescribed Rangeland Burning - Tallgrass Prairie

Fire Information Data

Inputs to SMARTFIRE2 for 2018 include:

•	The National Oceanic and Atmospheric Administration's (NOAA's) Hazard Mapping System
(HMS) fire location information

•	GeoMAC (Geospatial Multi-Agency Coordination), an online wildfire mapping application
designed for fire managers to access maps of current fire locations and perimeters in the
United States

•	The Incident Status Summary, also known as the "ICS-209", used for reporting specific
information on fire incidents of significance

•	Incident reports including dates of fire activity, acres burned, and fire locations from the
National Association of State Foresters (NASF)

•	Hazardous fuel treatment reduction polygons for prescribed burns from the Forest Service
Activity Tracking System (FACTS)

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•	Fire activity on federal lands from the United States Fish and Wildlife Service (USFWS)

•	Wildfire and prescribed date, location, and locations from a few S/L/T activity submitters
(includes Georgia, Florida and Kanas(Flint Hills only))

The Hazard Mapping System (HMS) was developed in 2001 by the National Oceanic and
Atmospheric Administration's (NOAA) National Environmental Satellite and Data Information
Service (NESDIS) as a tool to identify fires over North America in an operational environment. The
system utilizes geostationary and polar orbiting environmental satellites. Automated fire detection
algorithms are employed for each of the sensors. When possible, HMS data analysts apply quality control
procedures for the automated fire detections by eliminating those that are deemed to be false and adding
hotspots that the algorithms have not detected via a thorough examination of the satellite imagery.

The HMS product used for the 2018 inventory consisted of daily comma-delimited files containing fire
detect information including latitude-longitude, satellite used, time detected, and other information. These
detects were processed through Satellite Mapping Automated Reanalysis Tool for Fire Incident
Reconciliation version 2 (SMARTFIRE2) and BlueSky Pipeline.

GeoMAC (Geospatial Multi-Agency Coordination) is an online wildfire mapping application designed for
fire managers to access maps of current U.S. fire locations and perimeters. The wildfire perimeter data is
based upon input from incident intelligence sources from multiple agencies, GPS data, and infrared (IR)
imagery from fixed wing and satellite platforms.

The Incident Status Summary, also known as the "ICS-209" is used for reporting specific information on
significant fire incidents. The ICS-209 report is a critical interagency incident reporting tool giving daily
'snapshots' of the wildland fire management situation and individual incident information which include
fire behavior, size, location, cost, and other information. Data from two tables in the ICS-209 database
were merged and used for the ptfire inventory: the SIT209_HISTORY_INCIDENT_209_REPORTS table
contained daily 209 data records for large fires, and the SIT209 HISTORY INCIDENTS table contained
summary data for additional smaller fires.

The National Association of State Foresters (NASF) is a non-profit organization composed of the
directors of forestry agencies in the states, U.S. territories, and District of Columbia to manage and protect
state and private forests, which encompass nearly two-thirds of the nation's forests. The NASF compiles
fire incident reports from agencies in the organization and makes them publicly available. The NASF fire
information includes dates of fire activity, acres burned, and fire location information.

Monitoring Trends in Burn Severity (MTBS) is an interagency program whose goal is to consistently map
the burn severity and extent of large fires across the U.S. from 1984 to present. The MTBS data includes
all fires 1,000 acres or greater in the western United States and 500 acres or greater in the eastern United
States. The extent of coverage includes the continental U.S., Alaska, Hawaii, and Puerto Rico. Fire
occurrence and satellite data from various sources are compiled to create numerous MTBS fire products.
The MTBS Burned Areas Boundaries Dataset shapefiles include year 2018 fires and that are classified as
either wildfires, prescribed burns, or unknown fire types. The unknown fire type shapes were omitted in
the inventory development due to temporal and spatial problems found when trying to use these data.

The US Forest Service (USFS) compiles a variety of fire information every year. Year 2018 data from the
USFS Natural Resource Manager (NRM) Forest Activity Tracking System (FACTS) were acquired and
used for emissions inventory development. This database includes information about activities related to
fire/fuels, silviculture, and invasive species. The FACTS database consists of shapefiles for prescribed
burns that provide acres burned and start and ending time information.

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The US Fish and Wildland Service (USFWS) also compiles wildfire and prescribed burn activity on their
federal lands every year. Year 2018 data were acquired from USFWS through direct communication with
USFWS staff and were used for 2018 platform development. The USFWS fire information provided fire
type, acres burned, latitude-longitude, and start and ending times.

Fire Emissions Estimation Methodology

The national and S/L/T data mentioned earlier were used to estimate daily wildfire and prescribed burn
emissions from flaming combustion and smoldering combustion phases for the 2018 inventory. Flaming
combustion is more complete combustion than smoldering and is more prevalent with fuels that have a
high surface-to-volume ratio, a low bulk density, and low moisture content. Smoldering combustion
occurs without a flame, is a less complete burn, and produces some pollutants, such as PM2.5, VOCs, and
CO, at higher rates than flaming combustion. Smoldering combustion is more prevalent with fuels that
have low surface-to-volume ratios, high bulk density, and high moisture content. Models sometimes
differentiate between smoldering emissions that are lofted with a smoke plume and those that remain near
the ground (residual emissions). For the purposes of the inventory the residual smoldering emissions were
allocated to the smoldering SCCs listed in Table 2-20, while the lofted smoldering emissions were
assigned to the flaming emissions SCCs.

Figure 2-9 is a schematic of the data processing stream for the inventory of wildfire and prescribed burn
sources. The ptfire-rx and ptfire-wild inventory sources were estimated using Satellite Mapping
Automated Reanalysis Tool for Fire Incident Reconciliation version 2 (SMARTFIRE2) and Blue Sky
Pipeline. SMARTFIRE2 is an algorithm and database system that operate within a geographic
information system (GIS). SMARTFIRE2 combines multiple sources of fire information and reconciles
them into a unified GIS database. It reconciles fire data from space-borne sensors and ground-based
reports, thus drawing on the strengths of both data types while avoiding double-counting of fire events. At
its core, SMARTFIRE2 is an association engine that links reports covering the same fire in any number of
multiple databases. In this process, all input information is preserved, and no attempt is made to reconcile
conflicting or potentially contradictory information (for example, the existence of a fire in one database
but not another).

For the 2018 platform, the national and S/L/T fire information was input into SMARTFIRE2 and then
merged and associated based on user-defined weights for each fire information dataset. The output from
SMARTFIRE2 was daily acres burned by fire type, and latitude-longitude coordinates for each fire. The
fire type assignments were made using the fire information datasets. If the only information for a fire was
a satellite detect for fire activity, then the flow described in Figure 2-10 was used to make fire type
assignment by state and by month.

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Figure 2-9. Processing flow for fire emission estimates

Input Data Sets
(state/local/tribal and national data sets)

* ^

Data Preparation



Data Aggregation and Reconciliation
(SmartFire2)



Daily fire locations
with fire size and type



Fuel Moisture and
Fuel Loading Data

Smoke Modeling (BlueSky Framework)

Daily smoke emissions
for each fire

Emissions Post-Processing

Final Wildland Fire Emissions Inventory


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The second system used to estimate emissions is the BlueSky Modeling Pipeline. The framework supports
the calculation of fuel loading and consumption, and emissions using various models depending on the
available inputs as well as the desired results. The contiguous United States and Alaska, where Fuel
Characteristic Classification System (FCCS) fuel loading data are available, were processed using the
modeling chain described in Figure 2-11. The Fire Emissions Production Simulator (FEPS) in the
BlueSky Pipeline generates all the CAP emission factors for wildland fires used in the 2018 study. HAP
emission factors were obtained from Urbanski's (2014) work and applied by region and by fire type.

The FCCSv3 cross-reference was implemented along with the LANDFIREvl (at 200 meter resolution) to
provide better fuel bed information for the BlueSky Pipeline (BSP). The LANDFIREv2 was aggregated
from the native resolution and projection to 200 meter using a nearest-neighbor methodology.

Aggregation and reprojection was required for the proper function on BSP.

The final products from this process are annual and daily FFlO-formatted emissions inventories. These
SMOKE-ready inventory files contain both CAPs and HAPs. The BAFM HAP emissions from the
inventory were used directly in modeling and were not overwritten with VOC speciation profiles (i.e., an
"integrate HAP" use case).

Figure 2-11. Blue Sky Pipeline

2.5.2 Point source Agriculture Fires (ptagfire)

In the NEI, agricultural fires are stored as county-annual emissions and are part of the nonpoint data
category. For this study agricultural fires are modeled as day specific fires derived from satellite data for
the year 2018 in a similar way to the emissions in ptfire. The state of Florida provided their own
emissions (separate from the other states) for this study.

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Daily year-specific agricultural burning emissions are derived from HMS fire activity data, which
contains the date and location of remote-sensed anomalies. The activity is filtered using the 2018 USDA
cropland data layer (CDL). Satellite fire detects over agricultural lands are assumed to be agricultural
burns and assigned a crop type. Detects that are not over agricultural lands are output to a separate file for
use in the ptfire sector. Each detect is assigned an average size of between 40 and 80 acres based on crop
type. Grassland/pasture fires were moved to the ptfire sectors for this 2018 modeling platform. Depending
on their origin, grassland fires are in both ptfire-rx and ptfire-wild sectors because both fire types do
involve grassy fuels.

The point source agricultural fire (ptagfire) inventory sector contains daily agricultural burning emissions.
Daily fire activity was derived from the NOAA Hazard Mapping System (HMS) fire activity data. The
agricultural fires sector includes SCCs starting with '28015'. The first three levels of descriptions for
these SCCs are: 1) Fires - Agricultural Field Burning; Miscellaneous Area Sources; 2) Agriculture
Production - Crops - as nonpoint; and 3) Agricultural Field Burning - whole field set on fire. The SCC
2801500000 does not specify the crop type or burn method, while the more specific SCCs specify field or
orchard crops and, in some cases, the specific crop being grown. The SCCs for this sector listed are in
Table 2-23.

Table 2-23. SCCs included in the ptagfire sector

SCC

Description

2801500000

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; Unspecified crop type and Burn Method

2801500141

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; Field Crop is Bean (red): Headfire Burning

2801500150

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; Field Crop is Corn: Burning Techniques Not Important

2801500151

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; Double Crop Winter Wheat and Corn

2801500152

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; DoubleCrop Corn and Soybeans

2801500160

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; Field Crop is Cotton: Burning Techniques Not Important

2801500171

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -

whole field set on fire; Fallow

2801500220

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; Field Crop is Rice: Burning Techniques Not Significant

2801500250

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; Field Crop is Sugar Cane: Burning Techniques Not Significant

2801500262

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; Field Crop is Wheat: Backfire Burning

2801500263

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; DoubleCrop Winter Wheat and Cotton

2801500264

Miscellaneous Area Sources; Agriculture Production - Crops - as nonpoint; Agricultural Field Burning -
whole field set on fire; DoubleCrop Winter Wheat and Soybeans

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Another feature of the ptagfire database is that the satellite detections for 2018 were filtered out to
exclude areas covered by snow during the winter months. To do this, the daily snow cover fraction per
grid cell was extracted from a 2018 meteorological Weather Research Forecast (WRF) model simulation.
The locations of fire detections were then compared with this daily snow cover file. For any day in which
a grid cell had snow cover, the fire detections in that grid cell on that day were excluded from the
inventory. Due to the inconsistent reporting of fire detections from the Visible Infrared Imaging
Radiometer Suite (VIIRS) platform, any fire detections in the HMS dataset that were flagged as VIIRS or
Suomi National Polar-orbiting Partnership satellite were excluded. In addition, certain crop types (corn
and soybeans) have been excluded from these specific midwestern states: Iowa, Kansas, Indiana, Illinois,
Michigan, Missouri, Minnesota, Wisconsin, and Ohio. The reason for these crop types being excluded is
because states have indicated that these crop types are not burned.

Heat flux for plume rise was calculated using the size and assumed fuel loading of each daily agricultural
fire. This information is needed for a plume rise calculation within a chemical transport modeling system.

The daily agricultural and open burning emissions were converted from a tabular format into the
SMOKE-ready daily point flat file format. The daily emissions were also aggregated into annual values
by location and converted into the annual point flat file format.

For this modeling platform, a SMOKE update allows the use of HAP integration for speciation for
PTDAY inventories. The 2018 agricultural fire inventories include emissions for HAPs, so HAP
integration was used for this study.

2.6 Biogenic Sources (beis)

Biogenic emissions were computed based on the 18j version of the 2018 meteorology data used for the air
quality modeling and were developed using the Biogenic Emission Inventory System version 3.7
(BEIS3.7) within CMAQ. The BEIS3.7 creates gridded, hourly, model-species emissions from vegetation
and soils. It estimates CO, VOC (most notably isoprene, terpene, and sesquiterpene), and NO emissions
for the contiguous U.S. and for portions of Mexico and Canada. In the BEIS 3.7 two-layer canopy model,
the layer structure varies with light intensity and solar zenith angle (Pouliot and Bash, 2015). Both layers
include estimates of sunlit and shaded leaf area based on solar zenith angle and light intensity, direct and
diffuse solar radiation, and leaf temperature (Bash et al., 2015). The new algorithm requires additional
meteorological variables over previous versions of BEIS. The variables output from the Meteorology-
Chemistry Interface Processor (MCIP) that are used to convert WRF outputs to CMAQ inputs are shown
in Table 2-24.

Table 2-24. Meteorological variables required by BEIS 3.7

Variable

Description

LAI

leaf-area index

PRSFC

surface pressure

Q2

mixing ratio at 2 m

RC

convective precipitation per met TSTEP

RGRND

solar rad reaching surface

RN

nonconvective precipitation per met TSTEP

RSTOMI

inverse of bulk stomatal resistance

SLYTP

soil texture type by USD A category

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Variable

Description

SOIM1

volumetric soil moisture in top cm

SOIT1

soil temperature in top cm

TEMPG

skin temperature at ground

USTAR

cell averaged friction velocity

RADYNI

inverse of aerodynamic resistance

TEMP2

temperature at 2 m

BEIS 3.7 was used in conjunction with Version 5 of the Biogenic Emissions Landuse Database (BELD5).
The BELD5 is based on an updated version of the USDA-USFS Forest Inventory and Analysis (FIA)
vegetation speciation-based data from 2001 to 2017 from the FIA version 8.0. Canopy coverage is based
on the Global Moderate Resolution Imaging Spectroradiometer (MODIS) 20 category data with enhanced
lakes and Fraction of Photosynthetically Active Radiation (FPAR) for vegetation coverage from National
Center for Atmospheric Research (NCAR). The FIA includes approximately 250,000 representative plots
of species fraction data that are within approximately 75 km of one another in areas identified as forest by
the MODIS canopy coverage. For land areas outside the conterminous United States, 500 meter grid
spacing land cover data from the Moderate Resolution Imaging Spectroradiometer (MODIS) is used.
BELDv5 also incorporates the following datasets:

Canadian BELD land use, updates to Version 4 of the Biogenic Emissions Landuse Database
(BELD4) for Canada and Impacts on Biogenic VOC Emissions
(https://www.epa.gov/sites/default/files/2019-08/documents/8Q0am zhang 2 O.pdf).

2017 30 meter USD A Cropland Data Layer (CDL) data
(http://www.nass.usda.gov/research/Cropland/Release/).

A minor bug correction was implemented in BEIS3 to correctly use a few agricultural landuse types in
BELD5 that resulted in a minor increase of 1.6% in nitric oxide emissions from soils for the CONUS
region. Additionally, a minor map projections issue was found in the BELD5 data used in 2018vl. This
was corrected in 2018v2 and resulted in a 0.1% increase in VOC in the CONUS region and a 2.3%
increase in VOC emissions in the Canadian provinces.

Biogenic emissions computed with BEIS were used to review and prepare summaries, but were left out of
the CMAQ-ready merged emissions in favor of inline biogenic emissions produced during the CMAQ
model run itself using the same algorithm described above but with finer time steps within the air quality
model.

2.7 Sources Outside of the United States

The emissions from Canada and Mexico are included as part of the emissions modeling sectors: othpt,
othar, othafdust, othptdust, onroadcan, and onroadmex. The "oth" refers to the fact that these emissions
are usually "other" than those in the U.S. state-county geographic FIPS, and the remaining characters
provide the SMOKE source types: "pt" for point, "ar" for area and nonroad mobile, "afdust" for area
fugitive dust (Canada only), and "ptdust" for point fugitive dust (Canada only). The onroad emissions for
Canada and Mexico are in the onroad can and onroad mex sectors, respectively.

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Emissions in these sectors were taken from the EQUATES 2016 inventories. Environment and Climate
Change Canada (ECCC) provided the following inventories for use in EQUATES 2016 and 2017
modeling, which are described in more detail below:

Agricultural livestock and fertilizer, point source format (othpt sector)

CMV were provided as area sources but converted to point (not currently used)

Agricultural fugitive dust, point source format (othptdust sector)

Other area source dust (othafdust sector)

Onroad (onroad can sector)

- Nonroad and rail (othar sector)

Other area sources (othar sector)

Canadian CMV inventories that had been included in this sector in past modeling platforms are included
in the cmv_clc2 and cmv_c3 sectors as hourly point sources. The 2017 NEI CMV included most coastal
waters of Canada and Mexico with emissions derived from AIS data. These NEI emissions were used for
all areas of Canada and Mexico in which they were available and are included in the cmv_clc2 and
cmv_c3 sectors. Both the C1C2 and C3 emissions were developed in a point source format with point
locations at the center of the 12km grid cells. Activity and corresponding emissions along the St.

Lawrence Seaway were not included in the NEI. This region was gapfilled with emissions provided by
ECCC that were apportioned to point sources on the centroids of 12km grid cells using the Canadian
commercial marine vessel surrogate (CA 945). The Canadian emissions were held flat from 2017 to 2018.

In addition to emissions inventories, the ECCC 2015 dataset also included temporal profiles, and
shapefiles for creating spatial surrogates. These profiles and surrogates were used for this study. Other
than the CB6 species of NBAFM present in the speciated point source data, there are no explicit HAP
emissions in these Canadian inventories.

2.7.1	Point Sources in Canada and Mexico (othpt, canada_ag, canada_og2D)

Canadian point source inventories provided by ECCC for the EQUATES project for 2016 were used as-is
for 2018. These inventories include emissions for airports and other point sources. The Canadian point
source inventory is pre-speciated for the CB6 chemical mechanism. Point sources in Mexico were
compiled based on inventories projected to from the Inventario Nacional de Emisiones de Mexico, 2016
(Secretaria de Medio Ambiente y Recursos Naturales (SEMARNAT)). As in the EQUATES project, the
2016 Mexico emissions were projected to 2018 using trends from the Community Emissions Data System
(CEDS) dataset. The point source emissions were converted to English units and into the FF10 format that
could be read by SMOKE, missing stack parameters were gapfilled using SCC-based defaults, and
latitude and longitude coordinates were verified and adjusted if they were not consistent with the reported
municipality. Only CAPs are covered in the Mexico point source inventory.

2.7.2	Fugitive Dust Sources in Canada (othafdust, othptdust)

Fugitive dust sources of particulate matter emissions excluding land tilling from agricultural activities,
were provided by Environment and Climate Change Canada (ECCC) as part of their 2016 emission
inventory. Different source categories were provided as gridded point sources and area (nonpoint) source
inventories. Gridded point source emissions resulting from land tilling due to agricultural activities were
provided as part of the ECCC 2016 emission inventory. The provided wind erosion emissions were
removed. The othptdust emissions have a monthly resolution. A transport fraction adjustment that reduces
dust emissions based on land cover types was applied to both point and nonpoint dust emissions, along

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with a meteorology-based (precipitation and snow/ice cover) zero-out of emissions when the ground is
snow covered or wet. The EQUATES 2016 inventory was used as-is with 2018 meteorology applied.

2.7.3	Nonpoint and Nonroad Sources in Canada and Mexico (othar)

ECCC provided year 2016 Canada province, and in some cases sub-province, resolution emissions from
for nonpoint and nonroad sources (othar). The nonroad sources were monthly while the nonpoint and rail
emissions were annual. The 2016 Canada nonroad emissions were projected to 2018 using US MOVES-
based trends. For Mexico, 2016 Mexico nonpoint and nonroad inventories at the municipio resolution
provided by SEMARNAT were used, and were projected to 2018 using trends from the Community
Emissions Data System (CEDS) dataset. All Mexico inventories were annual resolution.

2.7.4	Onroad Sources in Canada and Mexico (onroad_can, onroad_mex)

The onroad emissions for Canada and Mexico are in the onroad can and onroadmex sectors,
respectively. Emissions for Canada come from the EQUATES 2016 (2016 was the latest year provided by
Environment and Climate Change Canada (ECCC)) and were projected from 2016 to 2018 using US
MOVES-based trends.

For Mexico onroad emissions, a version of the MOVES model for Mexico was run that provided the same
VOC HAPs and speciated VOCs as for the U.S. MOVES model (ERG, 2016a). This includes NBAFM
plus several other VOC HAPs such as toluene, xylene, ethylbenzene and others. Except for VOC HAPs
that are part of the speciation, no other HAPs are included in the Mexico onroad inventory (such as
particulate HAPs nor diesel particulate matter). Mexico onroad inventories were generated by MOVES
for the years 2017 and 2020, and then interpolated to 2018 for this study.

2.7.5	Fires in Canada and Mexico (ptfire_othna)

Annual 2018 wildland fire emissions for Mexico, Canada, Central America, and Caribbean nations are
included in the ptfireothna sector. Canadian fires, along with fires in Mexico, Central America, and the
Caribbean, were developed from Fire Inventory from NCAR (FINN) 2017 vl.5 daily fire emissions. For
FINN fires, listed vegetation type codes of 1 and 9 are defined as agricultural burning, all other fire
detections and assumed to be wildfires. All wildland fires that are not defined as agricultural are assumed
to be wildfires rather than prescribed. FINN fire detects of less than 50 square meters (0.012 acres) are
removed from the inventory. The locations of FINN fires are geocoded from latitude and longitude to
FIPS code.

2.7.6	Fires in Canada and Mexico (ptfire_othna)

Annual 2018 wildland fire emissions for Mexico, Canada, Central America, and Caribbean nations are
included in the ptfire othna sector. Canadian fires, along with fires in Mexico, Central America, and the
Caribbean, were developed from Fire Inventory from NCAR (FINN) 2017 vl.5 daily fire emissions. For
FINN fires, listed vegetation type codes of 1 and 9 are defined as agricultural burning, all other fire
detections and assumed to be wildfires. All wildland fires that are not defined as agricultural are assumed
to be wildfires rather than prescribed. FINN fire detects of less than 50 square meters (0.012 acres) are
removed from the inventory. The locations of FINN fires are geocoded from latitude and longitude to
FIPS code.

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2.7.7 Ocean Chlorine, Ocean Sea Salt, and Volcanic Mercury

The ocean chlorine gas emission estimates are based on the build-up of molecular chlorine (Cb)
concentrations in oceanic air masses (Bullock and Brehme, 2002). Data at 36 km and 12 km resolution
were available and were not modified other than the model-species name "CHLORINE" was changed to
"CL2" to support CMAQ modeling.

For mercury, the same volcanic mercury emissions were used as in the last several modeling platforms.
The emissions were originally developed for a 2002 multipollutant modeling platform with coordination
and data from Christian Seigneur and Jerry Lin for 2001 (Seigneur et. al, 2004 and Seigneur et. al, 2001).

Because of mercury bidirectional flux within the latest version of CMAQ, the only natural mercury
emissions included in the merge are from volcanoes.

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3 Emissions Modeling

The CMAQ and CAMx air quality models require hourly emissions of specific gas and particle species
for the horizontal and vertical grid cells contained within the modeled region (i.e., modeling domain). To
provide emissions in the form and format required by the model, it is necessary to "pre-process" the "raw"
emissions (i.e., emissions input to SMOKE) for the sectors described above in Section 2. In brief, the
process of emissions modeling transforms the emissions inventories from their original temporal
resolution, pollutant resolution, and spatial resolution into the hourly, speciated, gridded and vertical
resolution required by the air quality model. Emissions modeling includes temporal allocation, spatial
allocation, and pollutant speciation. Emissions modeling sometimes includes the vertical allocation (i.e.,
plume rise) of point sources, but many air quality models also perform this task because it greatly reduces
the size of the input emissions files if the vertical layers of the sources are not included.

As discussed in Section 2, the temporal resolutions of the emissions inventories input to SMOKE vary
across sectors and may be hourly, daily, monthly, or annual total emissions. The spatial resolution may be
individual point sources; totals by county (U.S.), province (Canada), or municipio (Mexico); or gridded
emissions. This section provides some basic information about the tools and data files used for emissions
modeling as part of the modeling platform.

3.1 Emissions modeling Overview

SMOKE version 4.8.1 was used to process the raw emissions inventories into emissions inputs for each
modeling sector into a format compatible with CMAQ, which were then converted to CAMx. For sectors
that have plume rise, the in-line plume rise capability allows for the use of emissions files that are much
smaller than full three-dimensional gridded emissions files. For quality assurance of the emissions
modeling steps, emissions totals by specie for the entire model domain are output as reports that are then
compared to reports generated by SMOKE on the input inventories to ensure that mass is not lost or
gained during the emissions modeling process.

When preparing emissions for the air quality model, emissions for each sector are processed separately
through SMOKE, and then the final merge program (Mrggrid) is run to combine the model-ready, sector-
specific 2-D gridded emissions across sectors. The SMOKE settings in the run scripts and the data in the
SMOKE ancillary files control the approaches used by the individual SMOKE programs for each sector.
Table 3-1 summarizes the major processing steps of each platform sector with the columns as follows.

The "Spatial" column shows the spatial approach used: "point" indicates that SMOKE maps the source
from a point location (i.e., latitude and longitude) to a grid cell; "surrogates" indicates that some or all of
the sources use spatial surrogates to allocate county emissions to grid cells; and "area-to-point" indicates
that some of the sources use the SMOKE area-to-point feature to grid the emissions (further described in
Section 3.4.2).

The "Speciation" column indicates that all sectors use the SMOKE speciation step, though biogenic
speciation is done within the Tmpbeis4 program and not as a separate SMOKE step.

The "Inventory resolution" column shows the inventory temporal resolution from which SMOKE needs
to calculate hourly emissions. Note that for some sectors (e.g., onroad, beis), there is no input inventory;
instead, activity data and emission factors are used in combination with meteorological data to compute
hourly emissions.

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Finally, the "plume rise" column indicates the sectors for which the "in-line" approach is used. These
sectors are the only ones with emissions in aloft layers based on plume rise. The term "in-line" means that
the plume rise calculations are done inside of the air quality model instead of being computed by
SMOKE. In all of the "in-line" sectors, all sources are output by SMOKE into point source files which are
subject to plume rise calculations in the air quality model. In other words, no emissions are output to layer
1 gridded emissions files from those sectors as has been done in past platforms. The air quality model
computes the plume rise using stack parameters, the Briggs algorithm, and the hourly emissions in the
SMOKE output files for each emissions sector. The height of the plume rise determines the model layers
into which the emissions are placed. The plume top and bottom are computed, along with the plumes'
distributions into the vertical layers that the plumes intersect. The pressure difference across each layer
divided by the pressure difference across the entire plume is used as a weighting factor to assign the
emissions to layers. This approach gives plume fractions by layer and source. Day-specific point fire
emissions are treated differently in CMAQ. After plume rise is applied, there are emissions in every layer
from the ground up to the top of the plume.

Table 3-1. Key emissions modeling steps by sector.

Platform sector

Spatial

Speciation

Inventory
resolution

Plume rise

afdust ad]

Surrogates

Yes

Annual



afdust ak adj
(36US3 only)

Surrogates

Yes

Annual



airports

Point

Yes

Annual

None

beis

Pre-gridded
land use and
biomass data

in BEIS3.7

computed hourly



Canada ag

Point

Yes

monthly

None

Canada og2D

Point

Yes

Annual

None

cmv clc2

Point

Yes

hourly

in-line

cmv c3

Point

Yes

hourly

in-line

fertilizer

Surrogates

No

monthly



livestock

Surrogates

Yes

Annual



nonpt

Surrogates &
area-to-point

Yes

Annual



nonroad

Surrogates

Yes

monthly



np oilgas

Surrogates

Yes

Annual



np solvents

Surrogates

Yes

annual



onroad

Surrogates

Yes

monthly activity,
computed hourly



onroadcaadj

Surrogates

Yes

monthly activity,
computed hourly



onroad nonconus
(36US3 only)

Surrogates

Yes

monthly activity,
computed hourly



onroad can

Surrogates

Yes

monthly



onroad mex

Surrogates

Yes

monthly



othafdust adj

Surrogates

Yes

annual



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Platform sector

Spatial

Speciation

Inventory
resolution

Plume rise

othar

Surrogates

Yes

annual &
monthly



othpt

Point

Yes

annual &
monthly

in-line

othptdust adj

Point

Yes

monthly

None

ptagfire

Point

Yes

daily

in-line

pt oilgas

Point

Yes

annual

in-line

ptegu

Point

Yes

daily & hourly

in-line

ptfire-rx

Point

Yes

daily

in-line

ptfire-wild

Point

Yes

daily

in-line

ptfire othna

Point

Yes

daily

in-line

ptnonipm

Point

Yes

annual

in-line

rail

Surrogates

Yes

annual



rwc

Surrogates

Yes

annual



Biogenic emissions can be modeled two different ways in the CMAQ model. The BEIS model within
SMOKE can produce gridded biogenic emissions that are then included in the gridded CMAQ-ready
emissions inputs, or alternatively, CMAQ can be configured to create "in-line" biogenic emissions within
CMAQ itself. For this platform, biogenic emissions were processed in SMOKE and included in the
gridded CMAQ-ready emissions. When CAMx is the targeted air quality model, BEIS is run within
SMOKE and the resulting emissions are included with the ground-level emissions input to CAMx.

In 2018v2, SMOKE was run in such a way that it produced both diesel and non-diesel outputs for onroad
and nonroad emissions that later get merged into the low-level emissions fed into the air quality model.
This facilitates advanced speciation treatments that are sometimes used in CMAQ. The onroad emissions
were processed in a single sector and were not split between gas and diesel for the 2032 case.

SMOKE has the option of grouping sources so that they are treated as a single stack when computing
plume rise. For this platform, no grouping was performed because grouping combined with "in-line"
processing will not give identical results as "offline" processing (i.e., when SMOKE creates 3-
dimensional files). This occurs when stacks with different stack parameters or latitudes/longitudes are
grouped, thereby changing the parameters of one or more sources. The most straightforward way to get
the same results between in-line and offline is to avoid the use of grouping.

For 2018gg, SMOKE was run for two modeling domains: a 36-km resolution CONtinental United States
"CONUS" modeling domain (36US3), and a 12-km resolution domain. For 2032, SMOKE was only run
at 12-km resolution. The domains are shown in Figure 3-1. More specifically, for each of the 12-km
resolution runs, SMOKE was run on the 12US1 domain and emissions were extracted from the 12US1
data files to create emissions for 12US2. Following the CMAQ run for 2018gg, the CMAQ outputs on the
36US3 grid were used to create boundary conditions for the 12US2 domain used for both 2018 and 2032.
All grids use a Lambert-Conformal projection, with Alpha = 33°, Beta = 45° and Gamma = -97°, with a
center of X = -97° and Y = 40°. Table 3-2 describes the grids for each of the domains.

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Figure 3-1. Air quality modeling domains

Table 3-2. Descriptions of the platform grids

Common

Name

Grid
Cell Size

Description
(see Figure 3-1)

Grid name

Parameters listed in SMOKE grid
description (GRIDDESC) file:
projection name, xorig, yorig, xcell,
ycell, ncols, nrows, nthik

Continental
36km grid

36 km

Entire conterminous
US, almost all of
Mexico, most of
Canada (south of
60°N)

36US3

'LAM 40N97W', -2952000, -2772000,
36.D3, 36.D3, 172, 148, 1

Continental
12km grid

12 km

Entire conterminous
US plus some of
Mexico/Canada

12US1_45 9X299

'LAM 40N97W, -2556000, -1728000,
12.D3, 12.D3, 459, 299, 1

US 12 km or
"smaller"
CONUS-12

12 km

Smaller 12km
CONUS plus some of
Mexico/Canada

12US2

'LAM 40N97W,-2412000,
-1620000, 12.D3, 12.D3, 396, 246, 1

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3.2 Chemical Speciation

The emissions modeling step for chemical speciation creates the "model species" needed by the air
quality model for a specific chemical mechanism. These model species are either individual chemical
compounds (i.e., "explicit species") or groups of species (i.e., "lumped species"). The chemical
mechanism used for the 2018 platform is the CB6R3AE7 mechanism (Yarwood, 2010, Luecken, 2019).
In CB6R3AE7, additional species that are not included in the CB6 chemical mechanism include acetic
acid (ACET), alpha pinene (APIN), formic acid (FACD), and intermediate volatility organic compounds
(IVOC). This mapping uses a new systematic methodology for mapping low volatility compounds.
Compounds with very low vapor pressure are mapped to model species NVOL and intermediate volatility
compounds are mapped to a species called IVOC. In previous mappings, some of these low vapor
pressure compounds were mapped to CB6 species. The mechanism and mapping are described in more
detail in a memorandum (Ramboll, 2020) describing the mechanism files supplied with the Speciation
Tool, the software used to create the CB6 profiles used in SMOKE. It should be noted that the onroad
mobile sector does not use this newer mapping because the speciation is done within MOVES and the
mapping change was made after MOVES had been run. This platform generates the PM2.5 model species
associated with the CMAQ Aerosol Module version 7 (AE7).

For 2018v2, the key changes to speciation involved updating some speciation cross references and using
newly available speciation profiles for solvents, oil and gas, and some point source SCCs. In addition, the
mapping for SOAALK species were updated to exclusively include linear and branched alkanes with
more than 8 carbons or cyclic alkanes with more than 6 carbons (Pye, 2012).

Table 3-3 lists the model species produced by SMOKE in the platform used for this study. Updates to
species assignments for CB05 and CB6 were made for the 2014v7.1 platform. These continue to be used
in the 2018v2 platform and are described in Appendix A.

Table 3-3. Emission model species produced for CB6R3AE7 for CMAQ

Inventory Pollutant

Model
Species

Model species description

Cl2

CL2

Atomic gas-phase chlorine

HC1

HCL

Hydrogen Chloride (hydrochloric acid) gas

CO

CO

Carbon monoxide

NOx

NO

Nitrogen oxide

NOx

N02

Nitrogen dioxide

NOx

HONO

Nitrous acid

S02

S02

Sulfur dioxide

S02

SULF

Sulfuric acid vapor

nh3

NH3

Ammonia

nh3

NH3 FERT

Ammonia from fertilizer

VOC

AACD

Acetic acid

VOC

ACET

Acetone

VOC

ALD2

Acetaldehyde

VOC

ALDX

Propionaldehyde and higher aldehydes

VOC

APIN

Alpha pinene

VOC

BENZ

Benzene (not part of CB05)

VOC

CH4

Methane

VOC

ETH

Ethene

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Inventory Pollutant

Model
Species

Model species description

VOC

ETHA

Ethane

VOC

ETHY

Ethyne

VOC

ETOH

Ethanol

VOC

FACD

Formic acid

VOC

FORM

Formaldehyde

VOC

IOLE

Internal olefin carbon bond (R-C=C-R)

VOC

ISOP

Isoprene

VOC

IVOC

Intermediate volatility organic compounds

VOC

KET

Ketone Groups

VOC

MEOH

Methanol

VOC

NAPH

Naphthalene

VOC

NVOL

Non-volatile compounds

VOC

OLE

Terminal olefin carbon bond (R-C=C)

VOC

PAR

Paraffin carbon bond

VOC

PRPA

Propane

VOC

SESQ

Sesquiterpenes (from biogenics only)

VOC

SOAALK

Secondary Organic Aerosol (SOA) tracer

VOC

TERP

Terpenes (from biogenics only)

VOC

TOL

Toluene and other monoalkyl aromatics

VOC

UNR

Unreactive

VOC

XYLMN

Xylene and other polyalkyl aromatics, minus naphthalene

Naphthalene

NAPH

Naphthalene from inventory

Benzene

BENZ

Benzene from the inventory

Acetaldehyde

ALD2

Acetaldehyde from inventory

Formaldehyde

FORM

Formaldehyde from inventory

Methanol

MEOH

Methanol from inventory

PMio

PMC

Coarse PM >2.5 microns and <10 microns

PM2.5

PEC

Particulate elemental carbon <2.5 microns

PM2.5

PN03

Particulate nitrate <2.5 microns

PM2.5

POC

Particulate organic carbon (carbon only) < 2.5 microns

PM2.5

PS04

Particulate Sulfate <2.5 microns

PM2.5

PAL

Aluminum

PM2.5

PCA

Calcium

PM2.5

PCL

Chloride

PM2.5

PFE

Iron

PM2.5

PK

Potassium

PM2.5

PH20

Water

PM2.5

PMG

Magnesium

PM2.5

PMN

Manganese

PM2.5

PMOTHR

PM2.5 not in other AE6 species

PM2.5

PNA

Sodium

PM2.5

PNCOM

Non-carbon organic matter

PM2.5

PNH4

Ammonium

PM2.5

PSI

Silica

PM2.5

PTI

Titanium

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One additional species in the emissions files but not in the above table is non-methane organic gases
(NMOG). This facilitates ongoing advanced work in speciation and is created using an additional GSPRO
component that creates NMOG for all TOG and NONHAPTOG profiles plus all integrate HAPs. This
species is not used for traditional ozone and particulate matter-focused modeling applications.

The TOG and PM2.5 speciation factors that are the basis of the chemical speciation approach for 2018v2
were developed from the SPECIATE 5.2 database (https://www.epa.gov/air-emissions-modeling/speciate-
2), the EPA's repository of TOG and PM speciation profiles of air pollution sources. Noting that the
2016v2 platform used profiles from a draft of SPECIATE 5.2. The SPECIATE database development and
maintenance is a collaboration involving the EPA's Office of Research and Development (ORD), Office
of Transportation and Air Quality (OTAQ), and the Office of Air Quality Planning and Standards
(OAQPS), in cooperation with ECCC (EPA, 2016). The SPECIATE database contains speciation profiles
for TOG, speciated into individual chemical compounds, VOC-to-TOG conversion factors associated
with the TOG profiles, and speciation profiles for PM2.5.

As with previous platforms, some Canadian point source inventories are provided from ECCC as pre-
speciated emissions; although not all CB6 species are provided. These inventories were not supplemented
with missing species due to the minimal impact of supplementation.

Speciation updates made for the 2016v3 platform that are also in the 2018v2 platform included:

•	Updated assignments to VOC profiles for 6 SCCs (all pulp and paper) and PM2.5 profiles for 3
SCCs (2 pulp and paper, 1 natural gas).

•	Updated profile assignments for solvents.

•	Re-mapped the profile for SCC 2310010200 from 2487 to 95247.

•	Remapped all point and nonpoint SCCs that were mapped to profile 1011 to 95404. The major
SCCs mapped to this profile are associated with oil production processes related fugitive
leaks/venting. Profile 95404 is a composite profile from untreated oil wells.

•	Remapped all point and nonpoint SCCs that were mapped to profile 1207 to profile 95782 (a
profile for produced water for non-coal bed methane). These are for non-CBM produced water.
We note that CBM produced water is using a Wyoming profile and 95782 is a non-CBM produced
water profile also sampled in Wyoming.

Updates to PM speciation cross references implemented in 2016v2 and carried into 2018v2 included:

•	where the comment says the "Heat Treating" profile should be used, changed the profile code to
91123 which is the actual Heat Treating profile;

•	for SCC 2801500250, changed to profile SUGP02 (a new sugar cane burning profile);

•	for SCC 30400740, changed to profile 95475;

•	used new fire profiles for fire PM. Note that all US states (not DC/HI/PR/VI) now use one of the
new profiles for all fire SCCs, including grassland fires. The profiles themselves aren't entirely
state-specific; there are four representative states for forest fires and two representative states for
grass fires, and all states are mapped to one of the four representative forest states and one of the
two representative grass states. The GSREFs still have a non-FIPS-specific assignment to the
previous profile 3766AE6 for fires outside of the United States.

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For additional information on speciation updates made in the prior platforms, see the 2016v3 platform
TSD (EPA, 2023a). Speciation profiles and cross references for this platform are available with the other
SMOKE input files for the platform. Emissions of VOC and PM2.5 by county, sector and profile for all
sectors other than onroad mobile can be found in the sector summaries for the case. Totals of each model
species by state and sector can be found in the state-sector totals workbook for this case.

3.2.1 VOC speciation

The speciation of VOC includes HAP emissions from the NEI in the speciation process. Instead of
speciating VOC to generate all species listed in Table 3-3, emissions of five specific HAPs from the NEI
were "integrated" with the NEI VOC. These HAPs include naphthalene, benzene, acetaldehyde,
formaldehyde, and methanol (collectively known as "NBAFM"). The integration combines these HAPs
with the VOC in a way that does not double count emissions and uses the HAP inventory directly in the
speciation process. The basic process is to subtract the specified HAPs emissions mass from the VOC
emissions mass, and to use a special "integrated" profile to speciate the remainder of VOC to the model
species excluding the specific HAPs. The EPA believes that the HAP emissions in the NEI are often more
representative of emissions than HAP emissions generated via VOC speciation, although this varies by
sector.

The NBAFM HAPs were chosen for integration because they are the only explicit VOC HAPs in the CB6
chemical mechanism. Explicit means that they are not lumped chemical groups like PAR, IOLE and
several other CB6 model species. These "explicit VOC HAPs" are model species that participate in the
modeled chemistry using the CB6 chemical mechanism. The use of inventory HAP emissions along with
VOC is called "HAP-CAP integration."

The integration of HAPs with VOC is a feature available in SMOKE for all inventory formats, including
PTDAY (the format used for the ptfire and ptagfire sectors). The ability to use integration with the
PTDAY format is used for the ptfire-rx and ptfire-wild sectors in this platform, but not for the ptagfire
sector which does not include HAPs.

SMOKE allows the user to specify the particular HAPs to integrate via the INVTABLE. This is done by
setting the "VOC or TOG component" field to "V" for all HAP pollutants chosen for integration. SMOKE
allows the user to also choose the particular sources to integrate via the NHAPEXCLUDE file (which
actually provides the sources to be excluded from integration11). For the "integrated" sources, SMOKE
subtracts the "integrated" HAPs from the VOC (at the source level) to compute emissions for the new
pollutant "NONHAPVOC." The user provides NONHAPVOC-to-NONHAPTOG factors and
NONHAPTOG speciation profiles.12 SMOKE computes NONHAPTOG and then applies the speciation
profiles to allocate the NONHAPTOG to the remaining air quality model VOC species. After determining
if a sector is to be integrated, if all sources have the appropriate HAP emissions, then the sector is
considered fully integrated and does not need a NHAPEXCLUDE file. On the other hand, if certain
sources do not have the necessary HAPs, then an NHAPEXCLUDE file must be provided based on the

11	Since SMOKE version 3.7, the options to specify sources for integration are expanded so that a user can specify the
particular sources to include or exclude from integration, and there are settings to include or exclude all sources within a sector.
In addition, the error checking is significantly stricter for integrated sources. If a source is supposed to be integrated, but it is
missing NBAFM or VOC, SMOKE will now raise an error.

12	These ratios and profiles are typically generated from the Speciation Tool when it is run with integration of a specified list of
pollutants, for example NBAFM.

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evaluation of each source's pollutant mix. The EPA considered CAP-HAP integration for all sectors in
determining whether sectors would have full, no, or partial integration (see Figure 3-2). For sectors with
partial integration, all sources are integrated other than those that have either the sum of NBAFM > VOC
or the sum of NBAFM = 0.

In this platform, NBAFM species are created from the no-integrate source VOC emissions using
speciation profiles and do not use HAPs from the inventory. Figure 3-2 illustrates the integrate and no-
integrate processes for U.S. sources. Since Canada and Mexico inventories do not contain HAPs, we use
the approach of generating the HAPs via speciation, except for Mexico onroad mobile sources where
emissions for integrate HAPs were available.

It should be noted that even though NBAFM were removed from the SPECIATE profiles used to create
the GSPRO for the NONHAPTOG profiles, there still may be small fractions for "BENZ", "FORM",
"ALD2", and "MEOH" present. This is because these model species may have come from species in
SPECIATE that are mixtures. The quantity of these model species is expected to be very small compared
to the BAFM in the NEI. There are no NONHAPTOG profiles that produce "NAPH."

Figure 3-2. Process of integrating NBAFM with VOC for use in VOC Speciation

i Emissions Ready for SMOKE

SMOKE

List of "no-integrate" sources
(NHAPEXCLUDE)

Speciation cross
reference file (GSREF)

NONHAPVOC to NONHAPTOG
factors (GSCNV)

NONHAPTOG speciation factors (GSPRO)
TOG speciation factors for which NBAFM
compounds removed prior to GSPRO creation

CMAQ-CB6 species

In SMOKE, the INVTABLE allows the user to specify the HAPs to integrate. Two different INVTABLE
files were used for different sectors of the platform. For sectors that had no integration across the entire
sector (see Table 3-4), a "no HAP use" INVTABLE in which the "KEEP" flag was set to "N" for
NBAFM pollutants was used. Thus, any NBAFM pollutants in the inventory input into SMOKE are
automatically dropped. This approach avoids double-counting of these species and assumes that the VOC
speciation is the best available approach for these species for sectors using this approach. The second

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INVTABLE, used for sectors in which one or more sources are integrated, causes SMOKE to keep the
inventory NBAFM pollutants and indicates that they are to be integrated with VOC. This is done by
setting the "VOC or TOG component" field to "V" for all five HAP pollutants. For the onroad and
nonroad sectors, "full integration" includes the integration of benzene, 1,3 butadiene, formaldehyde,
acetaldehyde, naphthalene, acrolein, ethyl benzene, 2,2,4-Trimethylpentane, hexane, propionaldehyde,
styrene, toluene, xylene, and methyl tert-butyl ether (MTBE).

Table 3-4. Integration of naphthalene, benzene, acetaldehyde, formaldehyde and methanol

(NBAFM) for each sector

Platform
Sector

Approach for Integrating NEI emissions of Naphthalene (N), Benzene (B),
Acetaldehyde (A), Formaldehyde (F) and Methanol (M)

ptegu

No integration, create NBAFM from VOC speciation

ptnonipm

No integration, create NBAFM from VOC speciation

ptfire-rx

Partial integration (NBAFM)

ptfire-wild

Partial integration (NBAFM)

ptfire othna

No integration, no NBAFM in inventory, create NBAFM from VOC speciation

ptagfire

Full integration (NBAFM)

airports

No integration, create NBAFM from VOC speciation

afdust

N/A - sector contains no VOC

beis

N/A - sector contains no inventory pollutant "VOC"; but rather specific VOC species

cmv clc2

Full integration (NBAFM)

cmv c3

Full integration (NBAFM)

fertilizer

N/A - sector contains no VOC

livestock

Partial integration (NBAFM)

rail

Full integration (NBAFM)

nonpt

Partial integration (NBAFM)

np solvents

Partial integration (NBAFM)

nonroad

Full integration (internal to MOVES)

np oilgas

Partial integration (NBAFM)

othpt

No integration, no NBAFM in inventory, create NBAFM from VOC speciation

pt oilgas

No integration, create NBAFM from VOC speciation

rwc

Full integration (NBAFM)

onroad

Full integration (internal to MOVES); however, MOVES2014a speciation was CB6-CAMx,
not CB6-CMAQ, so post-SMOKE emissions were converted to CB6-CMAQ

onroad can

No integration, no NBAFM in inventory, create NBAFM from speciation

onroadmex

Full integration (internal to MOVES-Mexico); however, MOVES-MEXICO speciation was
CB6-CAMx, not CB6-CMAQ, so post-SMOKE emissions were converted to CB6-CMAQ

othafdust

N/A - sector contains no VOC

othptdust

N/A - sector contains no VOC

othar

No integration, no NBAFM in inventory, create NBAFM from VOC speciation

Canada ag

No integration, no NBAFM in inventory, create NBAFM from speciation

Canada og2D

No integration, no NBAFM in inventory, create NBAFM from speciation

Integration for the mobile sources estimated from MOVES (onroad and nonroad sectors, other than for
California) is done differently. Briefly, there are three major differences: 1) for these sources integration
is done using more than just NBAFM, 2) all sources from the MOVES model are integrated, and 3)
integration is done fully or partially within MOVES. For onroad mobile, speciation is done fully within
MOVES3 such that the MOVES model outputs emission factors for individual VOC model species along
with the HAPs. This requires MOVES to be run for a specific chemical mechanism. For this platform

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MOVES was run for the CB6R3AE7 mechanism. Following the run of SMOKE-MOVES, NMOG
emissions were added to the data files through a post-SMOKE processor.

For nonroad mobile, speciation is partially done within MOVES such that it does not need to be run for a
specific chemical mechanism. For nonroad, MOVES outputs emissions of HAPs and NONHAPTOG are
split by speciation profile. Taking into account that integrated species were subtracted out by MOVES
already, the appropriate speciation profiles are then applied in SMOKE to get the VOC model species.
HAP integration for nonroad uses the same additional HAPs and ethanol as for onroad.

3.2.1.1 County specific profile combinations

SMOKE can compute speciation profiles from mixtures of other profiles in user-specified proportions via
two different methods. The first method, which uses a GSPROCOMBO file, has been in use since the
2005 platform; the second method (GSPRO with fraction) was used for the first time in the 2014v7.0
platform. The GSPRO COMBO method uses profile combinations specified in the GSPRO COMBO
ancillary file by pollutant (which can include emissions mode, e.g., EXH VOC), state and county (i.e.,
state/county FIPS code) and time period (i.e., month). Different GSPRO COMBO files can be used by
sector, allowing for different combinations to be used for different sectors; but within a sector, different
profiles cannot be applied based on SCC. The GSREF file indicates that a specific source uses a
combination file with the profile code "COMBO." SMOKE computes the resultant profile using the
fraction of each specific profile assigned by county, month and pollutant.

A GSPRO COMBO is used to specify a mix of E0 and E10 fuels in Canada. ECCC provided percentages
of ethanol use by province, and these were converted into E0 and E10 splits. For example, Alberta has
4.91% ethanol in its fuel, so we applied a mix of 49.1% E10 profiles (4.91% times 10, since 10% ethanol
would mean 100% E10), and 50.9% E0 fuel. Ethanol splits for all provinces in Canada are listed in Table
3-5. The Canadian onroad inventory includes four distinct FIPS codes in Ontario, allowing for application
of different E0/E10 splits in Southern Ontario versus Northern Ontario. In Mexico, only E0 profiles are
used.

Table 3-5. Ethanol percentages by volume by Canadian province

Province

Ethanol % by volume (E10 = 10%)

Alberta

4.91%

British Columbia

5.57%

Manitoba

9.12%

New Brunswick

4.75%

Newfoundland & Labrador

0.00%

Nova Scotia

0.00%

NW Territories

0.00%

Nunavut

0.00%

Ontario (Northern)

0.00%

Ontari o ( S outhern)

7.93%

Prince Edward Island

0.00%

Quebec

3.36%

Saskatchewan

7.73%

Yukon

0.00%

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A new method to combine multiple profiles became available in SMOKE4.5. It allows multiple profiles to
be combined by pollutant, state and county (i.e., state/county FIPS code) and SCC. This was used
specifically for the oil and gas sectors (pt oilgas and np oilgas) because SCCs include both controlled
and uncontrolled oil and gas operations which use different profiles.

3.2.1.2 Additional sector specific considerations for integrating HAP
emissions from inventories into speciation

The decision to integrate HAP emissions into the speciation was made on a sector-by-sector basis. For
some sectors, there is no integration and VOC is speciated directly; for some sectors, there is full
integration meaning all sources are integrated; and for other sectors, there is partial integration, meaning
some sources are not integrated and other sources are integrated. The integrated HAPs are either NBAFM
or, in the case of MOVES (onroad, nonroad, and MOVES-Mexico), a larger set of HAPs plus ethanol are
integrated. Table 3-4 above summarizes the integration method for each platform sector.

Speciation for the onroad sector is unique. First, SMOKE-MOVES is used to create emissions for these
sectors and both the MEPROC and INVTABLE files are involved in controlling which pollutants are
processed. Second, the speciation occurs within MOVES itself, not within SMOKE. The advantage of
using MOVES to speciate VOC is that during the internal calculation of MOVES, the model has complete
information on the characteristics of the fleet and fuels (e.g., model year, ethanol content, process, etc.),
thereby allowing it to more accurately make use of specific speciation profiles. This means that MOVES
produces emission factor tables that include inventory pollutants (e.g., TOG) and model-ready species
(e.g., PAR, OLE, etc).13 SMOKE essentially calculates the model-ready species by using the appropriate
emission factor without further speciation.14 Third, MOVES' internal speciation uses full integration of
an extended list of HAPs beyond NBAFM (called "M-profiles"). The M-profiles integration is very
similar to NBAFM integration explained above except that the integration calculation (see Figure 3-2) is
performed on emissions factors instead of on emissions, and a much larger set of pollutants are integrated
besides NBAFM. The list of integrated pollutants is described in Table 3-6. An additional run of the
Speciation Tool was necessary to create the M-profiles that were then loaded into the MOVES default
database. Fourth, for California, the EPA applied adjustment factors to SMOKE-MOVES to produce
California adjusted model-ready files. By applying the ratios through SMOKE-MOVES, the CARB
inventories are essentially speciated to match EPA estimated speciation. This resulted in changes to the
VOC HAPs from what CARB submitted to the EPA.

Table 3-6. MOVES integrated species in M-profiles

MOVES ID

Pollutant Name

5

Methane (CH4)

20

Benzene

21

Ethanol

22

MTBE

24

1,3-Butadiene

25

Formaldehyde

13	Because the EF table has the speciation "baked" into the factors, all counties that are in the county group (i.e., are mapped to
that representative county) will have the same speciation.

14	For more details on the use of model-ready EF, see the SMOKE 3.7 documentation:
https ://www. cmascenter. org/smoke/documentation/3.7/html/.

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MOVES ID

Pollutant Name

26

Acetaldehyde

27

Acrolein

40

2,2,4-Trimethylpentane

41

Ethyl Benzene

42

Hexane

43

Propionaldehyde

44

Styrene

45

Toluene

46

Xylene

185

Naphthalene gas

For the nonroad sector, all sources are integrated using the same list of integrated pollutants as shown in
Table 3-6. The integration calculations are performed within MOVES. For California and Texas, all VOC
HAPs were recalculated using MOVES HAP/VOC ratios based on the MOVES run so that VOC
speciation methodology would be consistent across the country. NONHAPTOG emissions by speciation
profile were also calculated based on MOVES data in California in Texas.

For nonroad emissions in California and Texas, where state-provided emissions were used, MOVES-style
speciation has been implemented in 2018gc and carried into 2018v2, with NONHAPTOG and PM2.5 pre-
split by profiles and with all the HAPs needed for VOC speciation augmented based on MOVES data in
CA and TX. This means in 2018gc and 2018v2, onroad emissions in California and Texas are speciated
consistently with the rest of the country.

MOVES-MEXICO for onroad used the same speciation approach as for the U.S. in that the larger list of
species shown in Table 3-6 was used. However, MOVES-MEXICO used an older version of the CB6
mechanism sometimes referred to as "CB6-CAMx." That mechanism is missing the model species
XYLMN and SOAALK and were added post-SMOKE as follows:

•	XYLMN = XYL[1]-0.966*NAPHTHALENE[1]

•	PAR = PAR[1]-0.00001*NAPHTHALENE[1]

•	SOAALK = 0.108*PAR[1]

The CB6R3AE7 mechanism includes other new species which are not part of CB6-CAMx, such as IVOC.
CB6R3AE7-specific species were not added to the MOVES-MEXICO emissions because those extra
species would be expected to have only a minor impact.

For the beis sector, the speciation profiles used by BEIS are not included in SPECIATE. BEIS4 includes
the species (SESQ) that is mapped to the BEIS model species SESQT (Sesquiterpenes). The profile code
associated with BEIS4 for use with CB05 is "B10C5," while the profile for use with CB6 is "B10C6."
The main difference between the profiles is the explicit treatment of acetone emissions in B10C6. The
biogenic speciation files are managed in the CMAQ Github repository.15

15 https://github.eom/USEPA/CMAO/blob/main/CCTM/src/bio g/beis4/gspro bio genics .txt.

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3.2.1.3 Oil and gas related speciation profiles

Several oil and gas profiles were developed or assigned to sources in np oilgas and pt oilgas to better
reflect region-specific differences in VOC composition and whether the process SCC would include
controlled emissions, considering the controls are not part of the SCC. For example, SCC 2310030300
(Gas Well Water Tank Losses) in Colorado are controlled by a 95% efficient flare, so a profile
(DJTFLR95) was developed to represent the composition of the VOC exiting the flare. Region-specific
profiles were also available for several areas, some of which were included in SPECIATE v5.1 and others
added to SPECIATE v5.2. These profiles are used in this platform and are listed in Appendix B.
Additional documentation is available in the SPECIATE database.

For the profiles in SPECIATE v5.2:

•	The Southern Ute profiles (SUIROGCT and SUIROGWT) applied to Archuleta and La Plata
counties in southwestern Colorado were developed from data provided in Tables 19 and 20 of the
report by Oakley Hayes, Matt Wampler, Danny Powers (December 2019), "Final Report for 2017
Southern Ute Indian Tribe Comprehensive Emissions Inventory for Criteria Pollutants, Hazardous
Air Pollutants, and Greenhouse Gases."16

•	A composite coal bed methane produced water profile, CBMPWWY, was developed by
compositing a subset of the SPECIATE 5.0 pond profiles associated with coal bed methane wells.
The SPECIATE 5.0 pond profiles were developed based on the publication: "Lyman, Seth N,
Marc L Mansfield, Huy NQ Tran, Jordan D Evans, Colleen Jones, Trevor O'Neil, Ric Bowers,
Ann Smith, and Cara Keslar. 2018. 'Emissions of Organic Compounds from Produced Water
Ponds I: Characteristics and Speciation', Science of the Total Environment, 619: 896-905."17 Note
that the pond profiles from this publication are included in SPECIATE 5.0; but a composite to
represent coal bed methane wells had not been developed for SPECIATE 5.0 and this new profile
is in SPECIATE 5.2.

•	The DJTFLR95 profile, DJ Condensate Flare Profile with DRE 95%, filled a need for the flared
condensate and produced water tanks for Colorado's oil and gas operations. This profile was
developed using the same approach as was used for the FLR99 (and other FLR**) SPECIATE 4.5
profiles, but instead of using profile 8949 for the uncombusted gas, it uses the Denver-Julesburg
Basin Condensate composite (95398) and it quantifies the combustion by-products based on a
95% DRE. The approach for combining profile 95398 with combustion by-products based on the
TCEQ's flare study (Allen, David T, and Vincent M Torres, University of Texas, Austin. 2011.
'TCEQ 2010 Flare Study Final Report', Texas Commission on Environmental Quality18) is the
same as used in the workbook for the FLR** SPECIATE4.5 profiles and can be found in the flr99
zip file referenced in the SPECIATE database. The approach uses the analysis developed by
Ramboll (Ramboll and EPA, 2017).

In addition to region-specific assignments, multiple profiles were assigned to select county/SCC
combinations using the SMOKE feature discussed in Section 3.2.1.1. Oil and gas SCCs for associated
gas, condensate tanks, crude oil tanks, dehydrators, liquids unloading and well completions represent the
total VOC from the process, including the portions of process that may be flared or directed to a reboiler.

16	https://www.southernute-nsn.gov/wp-content/uploads/sites/15/2019/12/191203-SUIT-CY2017-Emissions-Inventorv-Report-
FINAL.pdf.

17	http://doi.Org/10.1016/i.scitotenv.2017.ll.161.

18	https://downloads.regulations.gov/EPA-HQ-OAR-2012-0133-0Q47/attachment 32.pdf.

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For example, SCC 2310021400 (gas well dehydrators) consists of process, reboiler, and/or flaring
emissions. There are not separate SCCs for the flared portion of the process or the reboiler. However, the
VOC associated with these three portions can have very different speciation profiles. Therefore, it is
necessary to have an estimate of the amount of VOC from each of the portions (process, flare, reboiler) so
that the appropriate speciation profiles can be applied to each portion. The Nonpoint Oil and Gas
Emission Estimation Tool generates an intermediate file which provides flare, non-flare (process), and
reboiler (for dehydrators) emissions for six source categories that have flare emissions: by county FIPS
and SCC code for the U.S. These fractions can vary by county FIPS, because they depend on the level of
controls, which is an input to the Oil and Gas Tool. The basin or region-specific profiles for oil and gas
sources used in this platform are shown in Table 3-7.

Table 3-7. Basin/Region-specific profiles for oil and gas

Profile Code

Description

Region (if
not in profile
name)

DJVNT R

Denver-Julesburg Basin Produced Gas Composition from Non-CBM Gas Wells



PNC01 R

Piceance Basin Produced Gas Composition from Non-CBM Gas Wells



PNC02 R

Piceance Basin Produced Gas Composition from Oil Wells



PNC03 R

Piceance Basin Flash Gas Composition for Condensate Tank



PNCDH

Piceance Basin, Glycol Dehydrator



PRBCB R

Powder River Basin Produced Gas Composition from CBM Wells



PRBCO R

Powder River Basin Produced Gas Composition from Non-CBM Wells



PRM01 R

Permian Basin Produced Gas Composition for Non-CBM Wells



SSJCB R

South San Juan Basin Produced Gas Composition from CBM Wells



SSJCO R

South San Juan Basin Produced Gas Composition from Non-CBM Gas Wells



SWFLA R

SW Wyoming Basin Flash Gas Composition for Condensate Tanks



SWVNT R

SW Wyoming Basin Produced Gas Composition from Non-CBM Wells



UNT01 R

Uinta Basin Produced Gas Composition from CBM Wells



WRBCO R

Wind River Basin Produced Gagres Composition from Non-CBM Gas Wells



95087a

Oil and Gas - Composite - Oil Field - Oil Tank Battery Vent Gas

East Texas

95109a

Oil and Gas - Composite - Oil Field - Condensate Tank Battery Vent Gas

East Texas

95417

Uinta Basin, Untreated Natural Gas



95418

Uinta Basin, Condensate Tank Natural Gas



95419

Uinta Basin, Oil Tank Natural Gas



95420

Uinta Basin, Glycol Dehydrator



95398

Composite Profile - Oil and Natural Gas Production - Condensate Tanks

Denver-
Julesburg

95399

Composite Profile - Oil Field - Wells

California

95400

Composite Profile - Oil Field - Tanks

California

95403

Composite Profile - Gas Wells

San Joaquin

UTUBOGC

Raw Gas from Oil Wells - Composite Uinta basin



UTUBOGD

Raw Gas from Gas Wells - Composite Uinta basin



UTUBOGE

Flash Gas from Oil Tanks - including Carbonyls - Composite Uinta basin



92


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Profile Code

Description

Region (if
not in profile
name)

UTUBOGF

Flash Gas from Condensate Tanks - including Carbonyls - Composite Uinta
basin



PAGAS01

Oil and Gas-Produced Gas Composition from Gas Wells-Greene Co, PA



PAGAS02

Oil and Gas-Produced Gas Composition from Gas Wells-Butler Co, PA



PAGAS03

Oil and Gas-Produced Gas Composition from Gas Wells-Washington Co, PA



SUIROGCT

Flash Gas from Condensate Tanks - Composite Southern Ute Indian Reservation



CMU01

Oil and Gas - Produced Gas Composition from Gas Wells - Central Montana
Uplift - Montana



WIL01

Oil and Gas - Flash Gas Composition from Tanks at Oil Wells - Williston Basin
North Dakota



WIL02

Oil and Gas - Flash Gas Composition from Tanks at Oil Wells - Williston Basin
Montana



WIL03

Oil and Gas - Produced Gas Composition from Oil Wells - Williston Basin
North Dakota



WIL04

Oil and Gas - Produced Gas Composition from Oil Wells - Williston Basin
Montana



3.2.1.4 Mobile source related VOC speciation profiles

The VOC speciation approach for mobile source and mobile source-related categories is customized to
account for the impact of fuels, engine types, and technologies. The impact of fuels also affects the parts
of the nonpt and ptnonipm sectors that are related to mobile sources such as portable fuel containers and
gasoline distribution.

The VOC speciation profiles for the nonroad sector other than for California are listed in Table 3-8. They
include new profiles (i.e., those that begin with "953") for 2-stroke and 4-stroke gasoline engines running
on EO and E10 and compression ignition engines with different technologies developed from recent EPA
test programs, which also supported the updated toxics emission factor in MOVES2014a (Reichle, 2015
and EPA, 2015b).

Table 3-8. TOG MOVES-SMOKE Speciation Profiles for Nonroad Emissions

Profile

Profile Description

Engine
Type

Engine
Technology

Engine
Size

Horse-
power
category

Fuel

Fuel
Sub-
type

Emission
Process

95327

SI 2-stroke EO

SI 2-stroke

All

All

All

Gasoline

EO

exhaust

95328

SI 2-stroke E10

SI 2-stroke

All

All

All

Gasoline

E10

exhaust

95329

SI 4-stroke EO

SI 4-stroke

All

All

All

Gasoline

EO

exhaust

95330

SI 4-stroke E10

SI 4-stroke

All

All

All

Gasoline

E10

exhaust

95331

CI Pre-Tier 1

CI

Pre-Tier 1

All

All

Diesel

All

exhaust

95332

CI Tier 1

CI

Tier 1

All

All

Diesel

All

exhaust

95333

CI Tier 2

CI

Tier 2 and 3

all

All

Diesel

All

exhaust

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Profile

Profile Description

Engine
Type

Engine
Technology

Engine
Size

Horse-
power
category

Fuel

Fuel
Sub-
type

Emission
Process

95333a

19

CI Tier 2

CI

Tier 4

<56 kW
(75 hp)

S

Diesel

All

exhaust

8775

ACES Phase 1 Diesel
Onroad

CI Tier 4

Tier 4

>=56 kW
(75 hp)

L

Diesel

All

exhaust

8753

EO Evap

SI

all

all

All

Gasoline

EO

evaporative

8754

E10 Evap

SI

all

all

All

Gasoline

E10

evaporative

8766

EO evap permeation

SI

all

all

All

Gasoline

EO

permeation

8769

E10 evap permeation

SI

all

all

All

Gasoline

E10

permeation

8869

EO Headspace

SI

all

all

All

Gasoline

EO

headspace

8870

E10 Headspace

SI

all

all

All

Gasoline

E10

headspace

1001

CNG Exhaust

All

all

all

All

CNG

All

exhaust

8860

LPG exhaust

All

all

all

All

LPG

All

exhaust

Speciation profiles for VOC in the nonroad sector account for the ethanol content of fuels across years. A
description of the actual fuel formulations can be found in the NEI TSD. For previous platforms, the EPA
used "COMBO" profiles to model combinations of profiles for EO and E10 fuel use, but beginning with
2014v7.0 platform, the appropriate allocation of EO and E10 fuels is performed within MOVES.

Combination profiles reflecting a combination of E10 and EO fuel use ideally would be used for sources
upstream of mobile sources such as portable fuel containers (PFCs) and other fuel distribution operations
associated with the transfer of fuel from bulk terminals to pumps (BTP), which are in the nonpt sector.
For these sources, ethanol may be mixed into the fuels, in which case speciation would change across
years. The speciation changes from fuels in the ptnonipm sector include BTP distribution operations
inventoried as point sources. Refinery-to-bulk terminal (RBT) fuel distribution and bulk plant storage
(BPS) speciation does not change across the modeling cases because this is considered upstream from the
introduction of ethanol into the fuel. The mapping of fuel distribution SCCs to PFC, BTP, BPS, and RBT
emissions categories can be found in Appendix C. In 2018v2 platform, these sources get E10 speciation.

Table 3-9 summarizes the different profiles utilized for the fuel-related sources in each of the sectors. The
term "COMBO" indicates that a combination of the profiles listed was used to speciate that subcategory
using the GSPRO COMBO file.

Table 3-9. Select mobile-related VOC profiles

Sector

Sub-category

Profile
number

Profile Description

nonroad
non-US

Gasoline exhaust

COMBO

Pre-Tier 2 E0 exhaust (8750a) and
Pre-Tier 2 E10 exhaust (8751a)

nonpt/
ptnonipm

PFC and BTP

COMBO

E0 headspace (8869) and
E10 headspace (8870)

nonpt/
ptnonipm

Bulk plant storage (BPS) and refine-
to-bulk terminal (RBT) sources

8870

E10 Headspace

19 95333a replaced 95333. This correction was made to remove alcohols due to suspected contamination. Additional
information is available in SPECIATE.

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The speciation of onroad VOC occurs completely within MOVES. MOVES accounts for fuel type and
properties, emission standards as they affect different vehicle types and model years, and specific
emission processes. Table 3-10 describes the M-profiles available to MOVES depending on the model
year range, MOVES process (processID), fuel sub-type (fuelSubTypelD), and regulatory class
(regClassID). While MOVES maps the liquid diesel profile to several processes, MOVES only estimates
emissions from refueling spillage loss (processID 19). The other evaporative and refueling processes from
diesel vehicles have zero emissions. Table 3-11 through Table 3-13 describe the meaning of these
MOVES codes. For a specific representative county and analytic year, there will be a different mix of
these profiles. For example, for HD diesel exhaust, the emissions will use a combination of profiles
8774M and 8775M depending on the proportion of HD vehicles that are pre-2007 model years (MY) in
that particular county. As that county is projected farther into the future, the proportion of pre-2007 MY
vehicles will decrease. A second example, for gasoline exhaust (not including E-85), the emissions will
use a combination of profiles 8756M, 8757M, 8758M, 8750aM, and 875 laM. Each representative county
has a different mix of these key properties and, therefore, has a unique combination of the specific M-
profiles. More detailed information on how MOVES speciates VOC and the profiles used is provided in
the technical document, "Speciation of Total Organic Gas and Particulate Matter Emissions from On-road
Vehicles in MOVES2014" (EPA, 2015c).

Table 3-10. Onroad M-profiles

Profile

Profile Description

Model Years

ProcessID

FuelSubTypelD

RegClassID

1001M

CNG Exhaust

1940-2050

1,2,15,16

30

48

4547M

Diesel Headspace

1940-2050

11

20,21,22

0

4547M

Diesel Headspace

1940-2050

12,13,18,19

20,21,22

10,20,30,40,41, 42,46,47,48

8753M

E0 Evap

1940-2050

12,13,19

10

10,20,30,40,41,42, 46,47,48

8754M

E10 Evap

1940-2050

12,13,19

12,13,14

10,20,30,40,41, 42,46,47,48

8756M

Tier 2 E0 Exhaust

2001-2050

1,2,15,16

10

20,30

8757M

Tier 2 E10 Exhaust

2001-2050

1,2,15,16

12,13,14

20,30

8758M

Tier 2 El5 Exhaust

1940-2050

1,2,15,16

15,18

10,20,30,40,41, 42,46,47,48

8766M

E0 evap permeation

1940-2050

11

10

0

8769M

E10 evap permeation

1940-2050

11

12,13,14

0

8770M

El5 evap permeation

1940-2050

11

15,18

0

8774M

Pre-2007 MY HDD
exhaust

1940-2006

1,2,15,16,17,90

20, 21, 22

40,41,42,46,47, 48

8774M

Pre-2007 MY HDD
exhaust

1940-2050

9120

20,21,22

46,47

8774M

Pre-2007 MY HDD
exhaust

1940-2006

1,2,15,16

20,21,22

20,30

8775M

2007+ MY HDD
exhaust

2007-2050

1,2,15,16

20, 21, 22

20,30

8775M

2007+ MY HDD
exhaust

2007-2050

1,2,15,16,17,90

20, 21, 22

40,41,42,46,47,48

8855M

Tier 2 E85 Exhaust

1940-2050

1,2,15,16

50, 51, 52

10,20,30,40,41, 42,46,47,48

8869M

E0 Headspace

1940-2050

18

10

10,20,30,40,41, 42,46,47,48

20 91 is the processed for APUs which are diesel engines not covered by the 2007 Heavy-Duty Rule, so the older technology
applies to all years.

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Profile

Profile Description

Model Years

ProcessID

FuelSubTypelD

RegClassID

8870M

E10 Headspace

1940-2050

18

12,13,14

10,20,30,40,41, 42,46,47,48

8871M

El5 Headspace

1940-2050

18

15,18

10,20,30,40,41, 42,46,47,48

8872M

El5 Evap

1940-2050

12,13,19

15,18

10,20,30,40,41, 42,46,47,48

8934M

E85 Evap

1940-2050

11

50,51,52

0

8934M

E85 Evap

1940-2050

12,13,18,19

50,51,52

10,20,30,40,41, 42,46,47,48

8750aM

Pre-Tier 2 EO exhaust

1940-2000

1,2,15,16

10

20,30

8750aM

Pre-Tier 2 EO exhaust

1940-2050

1,2,15,16

10

10,40,41,42,46,47,48

875 laM

Pre-Tier 2 E10 exhaust

1940-2000

1,2,15,16

11,12,13,14

20,30

875 laM

Pre-Tier 2 E10 exhaust

1940-2050

1,2,15,16

11,12,13,14,15,
1821

10,40,41,42,46,47,48

95120m

Liquid Diesel

19602060

11

20,21,22

0

95120m

Liquid Diesel

19602060

12,13,18,19

20,21,22

10,20,30,40,41,42,46,47,48

95335a

2010+MY HDD
exhaust

20102060

1,2,15,16,17,90

20,21,22

40,41,42,46,47,48

m While MOVES maps the liquid diesel profile to several processes, MOVES only estimates emissions from
refueling spillage loss (processID 19). Other evaporative and refueling processes from diesel vehicles have zero
emissions.

Table 3-11. MOVES process IDs

Process ID

Process Name

1

Running Exhaust*

2

Start Exhaust

9

Brakewear

10

Tirewear

11

Evap Permeation

12

Evap Fuel Vapor Venting

13

Evap Fuel Leaks

15

Crankcase Running Exhaust*

16

Crankcase Start Exhaust

17

Crankcase Extended Idle Exhaust

18

Refueling Displacement Vapor Loss

19

Refueling Spillage Loss

20

Evap Tank Permeation

21

Evap Hose Permeation

22

Evap RecMar Neck Hose Permeation

23

Evap RecMar Supply/Ret Hose Permeation

24

Evap RecMar Vent Hose Permeation

30

Diurnal Fuel Vapor Venting

31

HotSoak Fuel Vapor Venting

21 The profile assignments for pre-2001 gasoline vehicles fueled on E15/E20 fuels (subtypes 15 and 18) were corrected for
MOVES2014a. This model year range, process, fuelsubtype regclass combination is already assigned to profile 8758.

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Process ID

Process Name

32

RunningLoss Fuel Vapor Venting

40

Nonroad

90

Extended Idle Exhaust

91

Auxiliary Power Exhaust

* Off-network idling is a process in MOVE S3 that is part ofprocesses 1 and 15
but assigned to road type 1 (off-network) instead of types 2-5

Table 3-12. MOVES Fuel subtype IDs

Fuel Subtype ID

Fuel Subtype Descriptions

10

Conventional Gasoline

11

Reformulated Gasoline (RFG)

12

Gasohol (E10)

13

Gasohol (E8)

14

Gasohol (E5)

15

Gasohol (E15)

18

Ethanol (E20)

20

Conventional Diesel Fuel

21

Biodiesel (BD20)

22

Fischer-Tropsch Diesel (FTD100)

30

Compressed Natural Gas (CNG)

50

Ethanol

51

Ethanol (E85)

52

Ethanol (E70)

Table 3-13. MOVES regclass IDs

Reg. Class ID

Regulatory Class Description

0

Doesn't Matter

10

Motorcycles

20

Light Duty Vehicles

30

Light Duty Trucks

40

Class 2b Trucks with 2 Axles and 4 Tires (8,500 lbs < GVWR <= 10,000 lbs)

41

Class 2b Trucks with 2 Axles and at least 6 Tires or Class 3 Trucks (8,500 lbs <
GVWR <= 14,000 lbs)

42

Class 4 and 5 Trucks (14,000 lbs < GVWR <= 19,500 lbs)

46

Class 6 and 7 Trucks (19,500 lbs < GVWR <= 33,000 lbs)

47

Class 8a and 8b Trucks (GVWR > 33,000 lbs)

48

Urban Bus (see CFR Sec 86.091 2)

For portable fuel containers (PFCs) and fuel distribution operations associated with the bulk-plant-to-
pump (BTP) distribution, a 10% ethanol mix (E10) was assumed for speciation purposes. Refinery to bulk
terminal (RBT) fuel distribution and bulk plant storage (BPS) speciation are considered upstream from
the introduction of ethanol into the fuel; therefore, a single profile is sufficient for these sources. No

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refined information on potential VOC speciation differences between cellulosic diesel and cellulosic
ethanol sources was available; therefore, cellulosic diesel and cellulosic ethanol sources used the same
SCC (30125010: Industrial Chemical Manufacturing, Ethanol by Fermentation production) for VOC
speciation as was used for corn ethanol plants.

3.2.2 PM speciation

In addition to VOC profiles, the SPECIATE database also contains profiles for speciating PM2.5. PM2.5
was speciated into the AE6 species associated with CMAQ 5.0.1 and later versions. Most of the PM
profiles come from the 911XX series (Reff et. al, 2009), which include updated AE6 speciation.22

The newest PM profile used in the 2018v2 platform is the Sugar Cane Pre-Harvest Burning Mexico
profile (SUGP02). This profile falls under the sector ptagfire and are included in SPECIATE v5.2.
Additionally, a series of regional fire profiles were added to SPECIATE 5.1 and are used in 2018v2.
These fall under the sector ptfire and are as shown in Table 3-14.

Table 3-14. Regional fire PM speciation profiles used in ptfire sectors

Pollutant

Profile
Code

Profile Description

PM

95793

Forest Fire-Flaming-Oregon AE6

PM

95794

Forest Fire-Smoldering-Oregon AE6

PM

95798

Forest Fire-Flaming-North Carolina AE6

PM

95799

Forest Fire-Smoldering-North Carolina AE6

PM

95804

Forest Fire-Flaming-Montana AE6

PM

95805

Forest Fire-Smoldering-Montana AE6

PM

95807

Forest Fire Understory-Flaming-Minnesota AE6

PM

95808

Forest Fire Understory-Smoldering-Minnesota AE6

PM

95809

Grass Fire-Field-Kansas AE6

3.2.2.1 Mobile source related PM2.5 speciation profiles

For the onroad sector, for all processes except brake and tire wear, PM speciation occurs within MOVES
itself, not within SMOKE (similar to the VOC speciation described above). The advantage of using
MOVES to speciate PM is that during the internal calculation of MOVES, the model has complete
information on the characteristics of the fleet and fuels (e.g., model year, sulfur content, process, etc.) to
accurately match to specific profiles. This means that MOVES produces EF tables that include total PM
(e.g., PM10 and PM2.5) and speciated PM (e.g., PEC, PFE). SMOKE essentially calculates the PM
components by using the appropriate EF without further speciation 23 The specific profiles used within
MOVES include two CNG profiles, 45219 and 45220, which were added to SPECIATE4.5. A list of
profiles is provided in the technical document, "Speciation of Total Organic Gas and Particulate Matter

22	The exceptions are 5675AE6 (Marine Vessel - Marine Engine - Heavy Fuel Oil) used for cmv_c3 and 92018 (Draft
Cigarette Smoke - Simplified) used in nonpt. 5675AE6 is an update of profile 5675 to support AE6 PM speciation.

23	Unlike previous platforms, the PM components (e.g., POC) are now consistently defined between MOVES2014 and CMAQ.
For more details on the use of model-ready EF, see the SMOKE 3.7 documentation:

https ://www. cmascenter. org/smoke/documentation/3.7/html/.

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Emissions from On-road Vehicles in MOVES2014" (EPA, 2015c). No changes to the mobile source PM
speciation profiles were made in the 2018v2 platform.

For onroad brake and tire wear, the PM is speciated in the moves2smk postprocessor that prepares the
emission factors for processing in SMOKE. The formulas for this are based on the standard speciation
factors from brake and tire wear profiles, which were updated from the v6.3 platform based on data from
a Health Effects Institute report (Schauer, 2006). These formulas are based on brake wear profile 95462
and tire wear profile 95460 and are as follows:

POC = 0.6395 * PM25TIRE + 0.0503 * PM25BRAKE
PEC = 0.0036 * PM25TIRE + 0.0128 * PM25BRAKE
PN03 = 0.000 * PM25TIRE + 0.000 * PM25BRAKE
PS04 = 0.0 * PM25TIRE + 0.0 * PM25BRAKE
PNH4 = 0.000 * PM25TIRE + 0.0000 * PM25BRAKE
PNCOM = 0.2558 * PM25TIRE + 0.0201 * PM25BRAKE

For California onroad emissions, adjustment factors were applied to SMOKE-MOVES to produce
California adjusted model-ready files. California did not supply speciated PM, therefore, the adjustment
factors applied to PM2.5 were also applied to the speciated PM components. By applying the ratios
through SMOKE-MOVES, the CARB inventories are essentially speciated to match EPA estimated
speciation.

For nonroad PM2.5, speciation is partially done within MOVES such that it does not need to be run for a
specific chemical mechanism. For nonroad, MOVES outputs emissions of PM2.5 split by speciation
profile. Similar to how VOC and NONHAPTOG are speciated, PM2.5 is now also speciated this way
starting with MOVES2014b. For California and Texas, PM2.5 emissions split by speciation profile are
estimated from total PM2.5 based on MOVES data in California and Texas, so that PM is speciated
consistently across the country. The PM2.5 profiles assigned to nonroad sources are listed in Table 3-15.

Table 3-15. Nonroad PM2.5 profiles

SPECIATE4.5
Profile Code

SPECIATE4.5 Profile Name

Assigned to Nonroad
sources based on Fuel Type

8996

Diesel Exhaust - Heavy-heavy duty truck -
2007 model year with NCOM

Diesel

91106

HDDV Exhaust - Composite

Diesel

91113

Nonroad Gasoline Exhaust - Composite

Gasoline

95219

CNG Transit Bus Exhaust

CNG and LPG

3.2.3 NOx speciation

NOx emission factors and therefore NOx inventories are developed on a NO2 weight basis. For air quality
modeling, NOx is speciated into NO, NO2, and/or HONO. For the non-mobile sources, the EPA used a
single profile "NHONO" to split NOx into NO and NO2.

The importance of HONO chemistry, identification of its presence in ambient air and the measurements of
HONO from mobile sources have prompted the inclusion of HONO in NOx speciation for mobile
sources. Based on tunnel studies, a HONO to NOx ratio of 0.008 was chosen (Sarwar, 2008). For the
mobile sources except for onroad (e.g., nonroad, cmv, rail, othon sectors), and for specific SCCs in othar

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and ptnonipm, the profile "HONO" is used. Table 3-16 gives the split factor for these two profiles. The
onroad sector does not use the "HONO" profile to speciate NOx. MOVES2014 produces speciated NO,
NO2, and HONO by source, including emission factors for these species in the emission factor tables used
by SMOKE-MOVES. Within MOVES, the HONO fraction is a constant 0.008 of NOx. The NO fraction
varies by heavy duty versus light duty, fuel type, and model year. The NO2 fraction = 1 - NO - HONO.
For more details on the NOx fractions within MOVES, see EPA report "Use of data from 'Development
of Emission Rates for the MOVES Model, 'Sierra Research, March 3, 2010" available at
https://nepis.epa. gov/Exe/ZyPDF.cgi?Dockev=Pl 00FlA5.pdf.

Table 3-16. NOx speciation profiles

Profile

pollutant

species

split factor

HONO

NOX

N02

0.092

HONO

NOX

NO

0.9

HONO

NOX

HONO

0.008

NHONO

NOX

N02

0.1

NHONO

NOX

NO

0.9

3.2.4 Creation of Sulfuric Acid Vapor (SULF)

Since the 2002 Platform, sulfuric acid vapor (SULF) has been estimated through the SMOKE speciation
process for coal combustion and residual and distillate oil fuel combustion sources. Profiles that compute
SULF from SO2 are assigned to coal and oil combustion SCCs in the GSREF ancillary file. The profiles
were derived from information from AP-42 (EPA, 1998), which identifies the fractions of sulfur emitted
as sulfate and SO2 and relates the sulfate as a function of S02.

Sulfate is computed from SO2 assuming that gaseous sulfate, which is comprised of many components, is
primarily H2SO4. The equation for calculating H2S04is given below.

Emissions of SULF (as H2S04)	Equation 3-1

fraction of S emitted as sulfate MW H2S04

= S07 emissions x —				-	x	

fraction of S emitted as S02 MW S02

In the above, MW is the molecular weight of the compound. The molecular weights of H2SO4 and SO2 are
98 g/mol and 64 g/mol, respectively.

This method does not reduce SO2 emissions; it solely adds gaseous sulfate emissions as a function of S02
emissions. The derivation of the profiles is provided in Table 3-17; a summary of the profiles is provided
in Table 3-18.

Table 3-17. Sulfate split factor computation

Fuel

SCCs

Profile
Code

Fraction
as S02

Fraction as
sulfate

Split factor (mass
fraction)

Bituminous

1-0X-002-YY, where X is 1,
2 or 3 and YY is 01 thru 19
and 21-ZZ-002-000 where
ZZ is 02,03 or 04

95014

0.95

0.014

.014/.95 * 98/64 =
0.0226

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Fuel

SCCs

Profile
Code

Fraction
as S02

Fraction as
sulfate

Split factor (mass
fraction)

Subbituminous

1-0X-002-YY, where X is 1,
2 or 3 and YY is 21 thru 38

87514

.875

0.014

.014/.875 * 98/64 =
0.0245

Lignite

1-0X-003-YY, where X is 1,
2 or 3 and YY is 01 thru 18
and 21-ZZ-002-000 where
ZZ is 02,03 or 04

75014

0.75

0.014

.014/.75 * 98/64 =
0.0286

Residual oil

1-0X-004-YY, where X is 1,
2 or 3 and YY is 01 thru 06
and 21-ZZ-005-000 where
ZZ is 02,03 or 04

99010

0.99

0.01

.01/ 99 * 98/64 =
0.0155

Distillate oil

1-0X-005-YY, where X is 1,
2 or 3 and YY is 01 thru 06
and 21-ZZ-004-000 where
ZZ is 02,03 or 04

99010

0.99

0.01

Same as residual oil

Table 3-18. SO2 speciation profiles

Profile

pollutant

species

split factor

95014

S02

SULF

0.0226

95014

S02

S02

1

87514

S02

SULF

0.0245

87514

S02

S02

1

75014

S02

SULF

0.0286

75014

S02

S02

1

99010

S02

SULF

0.0155

99010

S02

S02

1

3.3 Temporal Allocation

Temporal allocation is the process of distributing aggregated emissions to a finer temporal resolution,
thereby converting annual emissions to hourly emissions as is required by CMAQ. While the total
emissions are important, the timing of the occurrence of emissions is also essential for accurately
simulating ozone, PM, and other pollutant concentrations in the atmosphere. Many emissions inventories
are annual or monthly in nature. Temporal allocation takes these aggregated emissions and distributes the
emissions to the hours of each day. This process is typically done by applying temporal profiles to the
inventories in this order: monthly, day of the week, and diurnal, with monthly and day-of-week profiles
applied only if the inventory is not already at that level of detail. For 2018v2, temporal profile
assignments to SCCs were updated for solvents and for some point and nonpoint SCCs. The new profiles
for solvents only impacted the diurnal profiles and are based on Gkatzelis et al. (2021).

The temporal factors applied to the inventory are selected using some combination of country, state,
county, SCC, and pollutant. Table 3-19 summarizes the temporal aspects of emissions modeling by
comparing the key approaches used for temporal processing across the sectors. In the table, "Daily
temporal approach" refers to the temporal approach for getting daily emissions from the inventory using
the SMOKE Temporal program. The values given are the values of the SMOKE L TYPE setting. The
"Merge processing approach" refers to the days used to represent other days in the month for the merge
step. If this is not "all," then the SMOKE merge step runs only for representative days, which could

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include holidays as indicated by the right-most column. The values given are those used for the SMOKE
M TYPE setting (see below for more information).

Table 3-19. Temporal settings used for the platform sectors in SMOKE

Platform sector
short name

Inventory
resolution(s)

Monthly
profiles
used?

Daily
temporal
approach

Merge
processing
approach

Process holidays
as separate days

afdust adj

Annual

Yes

week

All

Yes

afdust ak adj

Annual

Yes

week

All

Yes

airports

Annual

Yes

week

week

Yes

beis

Hourly

No

n/a

All

No

Canada ag

Monthly

No

mwdss

mwdss

No

Canada og2D

Annual

Yes

mwdss

mwdss

No

cmv clc2

Annual

Yes

aveday

aveday

No

cmv c3

Annual

Yes

aveday

aveday

No

fertilizer

Monthly

No

All

all

No

livestock

Annual

Yes

All

all

No

nonpt

Annual

Yes

week

week

Yes

nonroad

Monthly

No

mwdss

mwdss

Yes

np oilgas

Annual

Yes

aveday

aveday

No

np solvents

Annual

Yes

aveday

aveday

No

onroad

Annual & monthly1

No

All

all

Yes

onroad ca adj

Annual & monthly1

No

All

all

Yes

onroad nonconus

Annual & monthly1

No

All

all

Yes

othafdust adj

Annual

Yes

week

all

No

othar

Annual & monthly

Yes

week

week

No

onroad can

Monthly

No

week

week

No

onroad mex

Monthly

No

week

week

No

othpt

Annual & monthly

Yes

mwdss

mwdss

No

othptdust adj

Monthly

No

week

all

No

pt oilgas

Annual

Yes

mwdss

mwdss

Yes

ptegu

Annual & hourly

Yes2

All

all

No

ptnonipm

Annual

Yes

mwdss

mwdss

Yes

ptagfire

Daily

No

All

all

No

ptfire-rx

Daily

No

All

all

No

ptfire-wild

Daily

No

All

all

No

ptfire othna

Daily

No

All

all

No

rail

Annual

Yes

aveday

aveday

No

rwc

Annual

No3

met-based3

All

No3

'Note the annual and monthly "inventory" actually refers to the activity data (VMT, hoteling, and VPOP) for onroad.
VMT and hoteling is monthly and VPOP is annual. The actual emissions are computed on an hourly basis.

2Only units that do not have matching hourly CEMS data use monthly temporal profiles.

3Except for 2 SCCs that do not use met-based temporal allocation.

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The following values are used in the table. The value "all" means that hourly emissions are computed for
every day of the year and that emissions potentially have day-of-year variation. The value "week" means
that hourly emissions computed for all days in one "representative" week, representing all weeks for each
month. This means emissions have day-of-week variation, but not week-to-week variation within the
month. The value "mwdss" means hourly emissions for one representative Monday, representative
weekday (Tuesday through Friday), representative Saturday, and representative Sunday for each month.
This means emissions have variation between Mondays, other weekdays, Saturdays and Sundays within
the month, but not week-to-week variation within the month. The value "aveday" means hourly emissions
computed for one representative day of each month, meaning emissions for all days within a month are
the same. Special situations with respect to temporal allocation are described in the following subsections.

In addition to the resolution, temporal processing includes a ramp-up period for several days prior to
January 1, 2018, which is intended to mitigate the effects of initial condition concentrations. The ramp-up
period was 10 days (December 22-31, 2017). For most sectors, emissions from December 2018
(representative days) were used to fill in emissions for the end of December 2017. For biogenic
emissions, December 2017 emissions were processed using 2017 meteorology.

3.3.1 Use of FF10 format for finer than annual emissions

The FF10 inventory format for SMOKE provides a consolidated format for monthly, daily, and hourly
emissions inventories. With the FF10 format, a single inventory file can contain emissions for all 12
months and the annual emissions in a single record. This helps simplify the management of numerous
inventories. Similarly, daily and hourly FF10 inventories contain individual records with data for all days
in a month and all hours in a day, respectively.

SMOKE prevents the application of temporal profiles on top of the "native" resolution of the inventory.
For example, a monthly inventory should not have annual-to-month temporal allocation applied to it;
rather, it should only have month-to-day and diurnal temporal allocation. This becomes particularly
important when specific sectors have a mix of annual, monthly, daily, and/or hourly inventories. The flags
that control temporal allocation for a mixed set of inventories are discussed in the SMOKE
documentation. The modeling platform sectors that make use of monthly values in the FF10 files are
livestock, nonroad, onroad, onroad can, onroadmex, othar, and othpt.

For livestock, meteorological-based temporalization (described in section 3.3.5) is used for month-to-day
and day-to-hour temporalization. Monthly profiles for livestock are based on the daily data underlying the
EPA estimates from 2014NEIv2.

3.3.2 Electric Generating Utility temporal allocation (ptegu)

3.3.2.1 Base year temporal allocation of EGUs

The temporal allocation procedure for EGUs in the base year is differentiated by whether or not the unit
could be directly matched to a unit with CEMS data via its ORIS facility code and boiler ID. Note that for
units matched to CEMS data, annual totals of their emissions input to CMAQ may be different than the
annual values in the 2018 annual inventory because the CEMS data replaces the NOx and SO2 annual
inventory data for the seasons in which the CEMS are operating. If a CEMS-matched unit is determined
to be a partial year reporter, as can happen for sources that run CEMS only in the summer, emissions
totaling the difference between the annual emissions and the total CEMS emissions are allocated to the

103


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non-summer months. Prior to use of the CEMS data in SMOKE it is processed through the CEMCorrect
tool. The CEMCorrect tool identifies hours for which the data were not measured as indicated by the data
quality flags in the CEMS data files. Unmeasured data can be filled in with maximum values and thereby
cause erroneously high values in the CEMS data. When data were flagged as unmeasured and the values
were found to be more than three times the annual mean for that unit, the data for those hours are replaced
with annual mean values (Adelman et al., 2012). These adjusted CEMS data were then used for the
remainder of the temporal allocation process described below (see Figure 3-3 for an example).

Figure 3-3. Eliminating unmeasured spikes in CEMS data

2016 January CEMs for 6068 3





2016 Original CEMs
2016 Corrected CEMs

V\ AfPlftA/\A - A

,0V°

K.OV



,0V"

F..OV

A®

v-1°
f,0

Date

,0^

«^v

rt>

,0V°

<*nv



In modeling platforms prior to 2016 beta, unmatched EGUs were temporally allocated using daily and
diurnal profiles weighted by CEMS values within an IPM region, season, and by fuel type (coal, gas, and
other). All unit types (peaking and non-peaking) were given the same profile within a region, season and
fuel bin. Units identified as municipal waste combustors (MWCs) or cogeneration units (cogens) were
given flat daily and diurnal profiles. Beginning with the 2016 beta platform and continuing for the 2018
platforms, the small EGU temporalization process considers peaking units.

The region, fuel, and type (peaking or non-peaking) were identified for each input EGU with CEMS data
that are used for generating profiles. The identification of peaking units was based on hourly heat input
data from the 2018 base year and the two previous years (2016 and 2017). The heat input was summed for
each year. Equation 3-2 shows how the annual heat input value is converted from heat units (BTU/year) to
power units (MW) using the unit-level heat rate (BTU/kWh) derived from the NEEDS v6 database. In
Equation 3-3 a capacity factor is calculated by dividing the annual unit MW value by the NEEDS v6 unit
capacity value (MW) multiplied by the hours in the year. A peaking unit was defined as any unit that had
a maximum capacity factor of less than 0.2 for every year (2016, 2017, and 2018) and a 3-year average
capacity factor of less than 0.1.

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Annual Unit Power Output

8760 Hourly HI	,MW\

(BTU) 1UUUlwi

NEEDS Heat Rate (~—¦)

nnual Unit Output (MW) =	(B"':i __ggEquation 3-2

nnual Unit Output (MW) =

Unit Capacity Factor

8760 Hourly HI	,MW\

(BTU)	\kW)	Equation 3-3

NEEDS Heat Rate (f^)

Input regions were determined from one of the eight EGU modeling regions based on MJO and climate
regions. Regions were used to group units with similar climate-based load demands. Region assignment is
made on a state level, where all units within a state were assigned to the appropriate region. Unit fuel
assignments were made using the primary NEEDS v6 fuel. Units fueled by bituminous, subbituminous, or
lignite are assigned to the coal fuel type. Natural gas units were assigned to the gas fuel type. Distillate
and residual fuel oil were assigned to the oil fuel type. Units with any other primary fuel were assigned
the "other" fuel type. The number of units used to calculate the daily and diurnal EGU temporal profiles
in the 2016 platform are shown in Figure 3-4 by region, fuel, and for peaking/non-peaking. The counts
should be similar for this platform. There are 64 unique profiles available based on 8 regions, 4 fuels, and
2 for peaking unit status (peaking and non-peaking).

Figure 3-4. Temporal Profile Input Unit Counts by Fuel and Peaking Unit Classification

(pcafc"j"»Tpejiiurq;

'rngjoVi ilB|
,9*:1W-2S~ TJ
al: 0 / 0 /
omer:0/ c

West North Certral.
(PMbrqftypeHunQ):

iewToy^i	

|

"alfig; 07,(1

HWE-WI	,

jpMfcn^rongMjuM):

feasTA) ', 1 J

13 r—r2



¦west 1 J—
(peakiini'ronpesliiog}:
coS : 0/3
137

'oil: 0 / 0
otHer.O/i

StSARM ^ ^
(peaUig/nanpcako9):
axi: 11166~"r
w.mi-xs—"v-

ci:w/8 \
other: 0 / S3 \

South <	

(peafcmg/norpealung):
coal: 0/97 |

9»?263VJ37<

O»:t8/0 	

other: 0/4 k

LAOCO

(pealurarixnpcjtonB)-

"foi'A/ 155

EGU Regions

¦	LADCO

¦	MANE-VU

~	Northwest

~	SESARM
I I South

~	Southwest

~	West

¦	West North Central

105


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The daily and diurnal profiles were calculated for each region, fuel, and peaking type group from the year
2018 CEMS heat input values. The heat input values were summed for each input group to the annual
level at each level of temporal resolution: monthly, month-of-day, and diurnal. The sum by temporal
resolution value was then divided by the sum of annual heat input in that group to get a set of
temporalization factors. Diurnal factors were created for both the summer and winter seasons to account
for the variation in hourly load demands between the seasons. For example, the sum of all hour 1 heat
input values in the group was divided by the sum of all heat inputs over all hours to get the hour 1 factor.
Each grouping contained 12 monthly factors, up to 31 daily factors per month, and two sets of 24 hourly
factors. The profiles were weighted by unit size where the units with more heat input have a greater
influence on the shape of the profile. Composite profiles were created for each region and type across all
fuels as a way to provide profiles for a fuel type that does not have hourly CEMS data in that region.
Figure 3-5 shows peaking and non-peaking daily temporal profiles for the gas fuel type in the LADCO
region. Figure 3-6 shows the diurnal profiles for the coal fuel type in the Mid-Atlantic Northeast Visibility
Union (MANE-VU) region.

Figure 3-5. Example Daily Temporal Profiles for the LADCO Region and the Gas Fuel Type

Daily Small EGU Profile for LADCO gas

2016

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Figure 3-6. Example Diurnal Temporal Profiles for the MANE-VU Region and the Coal Fuel Type

Diurnal Small EGU Profile for MANE-VU coal

SMOKE uses a cross reference file to select a monthly, daily, and diurnal profile for each source. For this
platform, the temporal profiles were assigned in the cross reference at the unit level to EGU sources
without hourly CEMS data. An inventory of all EGU sources without CEMS data was used to identify the
region, fuel type, and type (peaking/non-peaking) of each source. As with the input unit the regions are
assigned using the state from the unit FIPS. The fuel was assigned by SCC to one of the four fuel types:
coal, gas, oil, and other. A fuel type unit assignment is made by summing the VOC, NOX, PM2.5, and
S02 for all SCCs in the unit. The SCC that contributed the highest total emissions to the unit for selected
pollutants was used to assign the unit fuel type. Peaking units were identified as any unit with an oil, gas,
or oil fuel type with a NAICS of 22111 or 221112. Some units may be assigned to a fuel type within a
region that does not have an available input unit with a matching fuel type in that region. These units
without an available profile for their group were assigned to use the regional composite profile. MWC and
cogen units were identified using the NEEDS primary fuel type and cogeneration flag, respectively, from
the NEEDS v6 database. The regions used to aggregate each profile group are shown in Figure 3-7. The
counts shown in this figure are from the 2016 platform. The numbers for this platform should be similar,
although not exactly the same.

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Figure 3-7. Non-CEMS EGU Temporal Profile Aggregation Regions

Small EGU 2016 Temporal Profile Application Counts

coal- 0 / 0
9K i

LADCO

(PN^W*pMli):

coal: 24/8
03/ 16

MANFVU
(pMfc/nonpetfk):

EGU

Regions

¦

LADCO

¦

MANE VU

~

Northwest

n

SESARM

~

South

~

Southwest

~

West

r~i

West North Central

3.3.2.2 Analytic year temporal allocation of EGUs

For analytic year temporal allocation of unit-level EGU emissions, estimates of average winter
(representing December through February), average winter shoulder (October through November and
March through April), and average summer (May through September) values were provided by the IPM
for all units. The winter shoulder was separated from the winter months starting with the 2016v3 platform
and the approach has been retained for this platform. The seasonal emissions for the analytic year cases
were produced by post processing of the IPM outputs. The unit-level data were converted into hourly
values through the temporal allocation process using a 3-step methodology: annualized summer/winter
value to month, month to day, and day to hour. CEMS data from the air quality analysis year (e.g., 2018)
is used as much as possible to temporally allocate the EGU emissions.

The goal of the temporal allocation process is to reflect the variability in the unit-level emissions that can
impact air quality over seasonal, daily, or hourly time scales, in a manner compatible with incorporating
analytic-year emission projections into analytic-year air quality modeling. The temporal allocation
process is applied to the seasonal emission projections for the three IPM seasons: summer (May through
September), winter shoulder (October through November and March through April), and winter
(December through February). The Flat File used as the input to the temporal allocation process contains
unit-level emissions and stack parameters (i.e., stack location and other characteristics consistent with
information found in the NEI). When the Flat File is produced from post-processed IPM outputs, a cross
reference is used to map the units in version 6 of the NEEDS database to the stack parameter and facility,
unit, release point, and process identifiers used in the NET This cross reference also maps sources to the
hourly CEMS data used to temporally allocate the emissions in the base year air quality modeling.

All units have seasonal information provided in the analytic year Flat File, the monthly values in the Flat
File input to the temporal allocation process are computed by multiplying the average summer day,

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average winter shield day, and average winter day emissions by the number of days in the respective
month. When generating seasonal emissions totals from the Flat File winter shield emissions are summed
with the winter emissions to create a total winter season. In summary, the monthly emission values shown
in the Flat File are not intended to represent an actual month-to-month emission pattern. Instead, they are
interim values that have translated IPM's seasonal projections into month-level data that serve as a
starting point for the temporal allocation process.

The monthly emissions within the Flat File undergo a multi-step temporal allocation process to yield the
hourly emission values at each unit, as is needed for air quality modeling: summer or winter value to
month, month to day, and day to hour. For sources not matched to unit-specific CEMS data, the first two
steps are done outside of SMOKE and the third step to get to hourly values is done by SMOKE using the
daily emissions files created from the first two steps. For each of these three temporal allocation steps,
NOx and SO2 CEMS data are used to allocate NOxand SO2 emissions, while CEMS heat input data are
used to allocate all other pollutants. The approach defined here gives priority to temporalization based on
the base year CEMS data to the maximum extent possible for both base and analytic year modeling.

Prior to using the 2018 CEMS data to develop monthly, daily, and hourly profiles, the CEMS data were
processed through the CEMCorrect tool to make adjustments for hours for which data quality flags
indicated the data were not measured and that the reported values were much larger than the annual mean
emissions for the unit. These adjusted CEMS data were used to compute the monthly, daily, and hourly
profiles described below.

For units that have CEMS data available and that have CEMS units matched to the NEI sources, the
emissions are temporalized according to the base year (i.e., 2018) CEMS data for that unit and pollutant.
For units that are not matched to the NEI or for which CEMS data are not available, the allocation of the
seasonal emissions to months is done using average fuel-specific season-to-month factors for both
peaking and non-peaking units generated for each of the eight regions shown in Figure 3-7. These factors
are based on a single year of CEMS data for the modeling base year associated with the air quality
modeling analysis being performed, such as 2018. The fuels used for creating the profiles for a region
were coal, natural gas, oil, and "other." The "other "fuels category is a broad catchall that includes fuels
such as wood and waste. Separate profiles are computed for NOx, SO2, and heat input, where heat input is
used to temporally allocate emissions for pollutants other than NOx and SO2. An overall composite profile
across all fuels is also computed and can be used in the event that a region has too few units of a fuel type
to make a reasonable average profile, or in the case when a unit changes fuels between the base and
analytic year and there were previously no units with that fuel in the region containing the unit. A
complete description of the generation and application of these regional fuel profiles is available in the
base year temporalization section.

The monthly emission values in the Flat File were first reallocated across the months in that season to
align the month-to-month emission pattern at each stack with historic seasonal emission patterns. While
this reallocation affects the monthly pattern of each unit's analytic-year seasonal emissions, the seasonal
totals are held equal to the IPM projection for that unit and season. Second, the reallocated monthly
emission values at each stack are disaggregated down to the daily level consistent with historic daily
emission patterns in the given month at the given stack using separate profiles for NOx, SO2, and heat
input. This process helps to capture the influence of meteorological episodes that cause electricity demand
to vary from day-to-day, as well as weekday-weekend effects that change demand during the course of a
given week. Third, this data set of emission values for each day of the year at each unit is input into
SMOKE, which uses temporal profiles to disaggregate the daily values into specific values for each hour
of the year.

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For units without or not matched to CEMS data, or for which the CEMS data are found to be unsuitable
for use in the analytic year, emissions were allocated from month to day using IPM-region and fuel-
specific average month-to-day factors based on CEMS data from the base year of the air quality modeling
analysis. These instances include units that did not operate in the base year or for which it may not have
been possible to match the unit to a specific unit in the NEI. Regional average profiles may be used for
some units with CEMS data in the base year when one of the following cases is true: (1) units are
projected to have substantially increased emissions in the analytic year compared to its emissions in the
base (historic) year; (2) CEMS data were only available for a limited number of hours in that base year;
(3) the unit is new in the analytic year; (4) when there were no CEMS data for one season in the base year
but IPM runs the unit during both seasons; or (5) units experienced atypical conditions during the base
year, such as lengthy downtimes for maintenance or installation of controls.

The temporal profiles that map emissions from days to hours were computed based on the region and
fuel-specific seasonal (i.e., winter and summer) average day-to-hour factors derived from the CEMS data
for heat input for those fuels and regions and for that season. Heat input was used because it is the
variable that is the most complete in the CEMS data and should be present for all of the hours in which
the unit was operating. SMOKE uses these diurnal temporal profiles to allocate the daily emissions data to
hours of each day. Note that this approach results in each unit having the same hourly temporal allocation
for all the days of a season.

The emissions from units for which unit-specific profiles were not used were temporally allocated to
hours reflecting patterns typical of the region in which the unit is located. Analysis of year 2016 CEMS
data for units in each of the 8 regions shown in Figure 3-4 revealed that there were differences in the
temporal patterns of historic emission data that correlate with fuel type (e.g., coal, gas, oil, and other),
time of year, pollutant, season (i.e., winter versus summer) and region of the country. The correlation of
the temporal pattern with fuel type is explained by the relationship of units' operating practices with the
fuel burned. For example, coal units take longer to ramp up and ramp down than natural gas units, and
some oil units are used only when electricity demand cannot otherwise be met. Geographically, the
patterns were less dependent on state location than they were on regional location. Figure 3-5 provides an
example of daily profiles for gas fuel in the LADCO region for 2016. The EPA developed year-specific
seasonal average emission profiles, each derived from base year CEMS data for each season across all
units sharing both IPM region and fuel type. Figure 3-6 provides an example of seasonal profiles that
allocate daily emissions to hours in the MANE-VU region. These average day-to-hour temporal profiles
were also used for sources during seasons of the year for which there were no CEMS data available, but
for which IPM predicted emissions in that season. This situation can occur for multiple reasons, including
how the CEMS was run at each source in the base year.

For units that do have CEMS data in the base year and were matched to units in the IPM output, the base
year CEMS data were scaled so that their seasonal emissions match the IPM-projected totals. The scaling
process used the fraction of the unit's seasonal emissions in the base year as computed for each hour of
the season, and then applied those fractions to the seasonal emissions from the analytic year Flat File. Any
pollutants other than NOx and SO2 were temporally allocated using heat input. Through the temporal
allocation process, the analytic year emissions will have the same temporal pattern as the base year CEMS
data, where available, while the analytic-year seasonal total emissions for each unit match the analytic-
year unit-specific projection for each season (see example in Figure 3-8). The year IPM output for 2030
maps to the year 2032 and was therefore used for the 2032 modeling case.

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In cases when the emissions for a particular unit are projected to be substantially higher in the analytic
year than in the base year, the proportional scaling method to match the emission patterns in the base year
described above can yield emissions for a unit that are much higher than the historic maximum emissions
for that unit. To help address this issue in the analytic case, the maximum measured emissions of NOx and
SO2 in the period of 2015-2019 were computed. The temporally allocated emissions were then evaluated
at each hour to determine whether they were above this maximum. The amount of "excess emissions"
over the maximum were then computed. For units for which the "excess emissions" could be reallocated
to other hours, those emissions were distributed evenly to hours that were below the maximum. Those
hourly emissions were then reevaluated against the maximum, and the procedure of reallocating the
excess emissions to other hours was repeated until all of the hours had emi ssions below the maximum,
whenever possible (see example in Figure 3-9).

Figure 3-8. Analytic Year Emissions Follow the Pattern of Base Year Emissions

2032 and 2018 Summer CEMs for 1379 4

Figure 3-9. Excess Emissions Apportioned to Hours Less than the Historic Maximum

2032 arwJ 2018 Summer CEMs for 55221 G1

2018 CEMS
2032 CEMS
2032 Adjusted CEMs
Annual unit max

mm

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Using the above approach, it was not always possible to reallocate excess emissions to hours below the
historic maximum, such as when the total seasonal emissions of NOx or SO2 for a unit divided by the
number of hours of operation are greater than the 2015-2019 maximum emissions level. For these units,
the regional fuel-specific average profiles were applied to all pollutants, including heat input, for the
respective season (see example in Figure 3-10). It was not possible for SMOKE to use regional profiles
for some pollutants and adjusted CEMS data for other pollutants for the same unit and season, therefore,
all pollutants in the unit and season are assigned to regional profiles when regional profiles are needed.
For some units, hourly emissions values still exceed the 2015-2019 annual maximum for the unit even
after regional profiles were applied (see example in Figure 3-11).

Figure 3-10. Regional Profile Applied due to not being able to Adjust below Historic Maximum

2032 and 2018 Summer CEMs for 6071 10

2018 CEMs
2032 C£Ms
2032 Adjusted CEMs
2032 Season Fuel
Annual unit max

May
2018

Figure 3-11. Regional Profile Applied, but Exceeds Historic Maximum in Some Hours

2032 and 2016 Summer CEMs for 55270.LM6

2018 CEMs
2032 CEMs

	 2032 Adjusted CEMs

2032 Season Fuel
Annual unit max

May	Jun	Jul	Aug	Sep

2018

Date

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3.3.3 Airport Temporal allocation (airports)

All airport SCCs (i.e., 2275*, 2265008005, 2267008005, 2268008005 and 2270008005) were given the
same hourly, weekly and monthly profile for all airports other than Alaska seaplanes. Hourly airport
operations data were obtained from the Aviation System Performance Metrics (ASPM) Airport Analysis
website (https://aspm.faa.gov/apm/svs/AnalvsisAP.asp). A report of 2014 hourly Departures and Arrivals
for Metric Computation was generated. An overview of the ASPM metrics is at

http://aspmhelp.faa.gov/index.php/Aviation Performance Metrics %28APM%29. Figure 3-12 shows the
diurnal airport profile.

Weekly and monthly temporal profiles are based on 2014 data from the FAA Operations Network Air
Traffic Activity System (http://aspm.faa.gov/opsnet/svs/Terminal.asp). An overview of the Operations
Network data system is here: http://aspmhelp.faa.gov/index.php/Operations Network %28QPSNET%29.
A report of all airport operations (takeoffs and landings) by day for 2014 was generated. These data were
then summed to month and day-of-week to derive the monthly and weekly temporal profiles shown in
Figure 3-12, Figure 3-13, and Figure 3-14. The weekly and monthly profiles from 2014 are used in this
platform. Note that Alaska seaplanes use the monthly profile shown in Figure 3-15. These were assigned
based on the facility ID.

Figure 3-12. Diurnal Profile for all Airport SCCs

Figure 3-13. Weekly profile for all Airport SCCs

Weekly Airport Profile

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Figure 3-14. Monthly Profile for all Airport SCCs
Monthly Airport Profile

0.05
0.04
0.03
0.02
0.01
0

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Figure 3-15. Alaska Seaplane Profile

0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

3.3.4 Residential Wood Combustion Temporal allocation (rwc)

There are many factors that impact the timing of when emissions occur, and for some sectors this includes
meteorology. The benefits of utilizing meteorology as a method for temporal allocation are: (1) a
meteorological dataset consistent with that used by the AQ model is available (e.g., outputs from WRF);
(2) the meteorological model data are highly resolved in terms of spatial resolution; and (3) the
meteorological variables vary at hourly resolution and can, therefore, be translated into hour-specific
temporal allocation.

The SMOKE program Gentpro provides a method for developing meteorology-based temporal allocation.
Currently, the program can utilize three types of temporal algorithms: annual-to-day temporal allocation
for residential wood combustion (RWC); month-to-hour temporal allocation for agricultural livestock
NH3; and a generic meteorology-based algorithm for other situations. Meteorological-based temporal
allocation was used for portions of the rwc sector and for agricultural livestock and fertilizer emissions.

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Gentpro reads in gridded meteorological data (output from MCIP) along with spatial surrogates and uses
the specified algorithm to produce a new temporal profile that can be input into SMOKE. The
meteorological variables and the resolution of the generated temporal profile (hourly, daily, etc.) depend
on the selected algorithm and the run parameters. For more details on the development of these algorithms
and running Gentpro, see the Gentpro documentation and the SMOKE documentation at
http://www.cmascenter.Org/smoke/documentation/3.l/GenTPRQ Technical Summary Aug2012 Final, pd
f and https://www.cmascenter.Org/smoke/documentation/4.5/html/ch05s03s05.html. respectively.

For the RWC algorithm, Gentpro uses the daily minimum temperature to determine the temporal
allocation of emissions to days of the year. Gentpro was used to create an annual-to-day temporal profile
for the RWC sources. These generated profiles distribute annual RWC emissions to the coldest days of
the year. On days where the minimum temperature does not drop below a user-defined threshold, RWC
emissions for most sources in the sector are zero. Conversely, the program temporally allocates the largest
percentage of emissions to the coldest days. Similar to other temporal allocation profiles, the total annual
emissions do not change, only the distribution of the emissions within the year is affected. The
temperature threshold for RWC emissions was 50 °F for most of the country, and 60 °F for the following
states: Alabama, Arizona, California, Florida, Georgia, Louisiana, Mississippi, South Carolina, and
Texas. The algorithm is as follows:

If Td >= Tt: no emissions that day
If Td < Tt: daily factor = 0.79*(Tt -Td)

where (Td = minimum daily temperature; Tt = threshold temperature, which is 60 degrees F in southern
states and 50 degrees F elsewhere).

Once computed, the factors are normalized to sum to 1 to ensure that the total annual emissions are
unchanged (or minimally changed) during the temporal allocation process.

Figure 3-16 illustrates the impact of changing the temperature threshold for a warm climate county. The
plot shows the temporal fraction by day for Duval County, Florida, for the first four months of 2007. The
default 50 °F threshold creates large spikes on a few days, while the 60 °F threshold dampens these spikes
and distributes a small amount of emissions to the days that have a minimum temperature between 50 and

60 °F.

Figure 3-16. Example of RWC temporal allocation using a 50 versus 60 °F threshold

RWC temporal profile, Duval County, FL, Jan - Apr

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The diurnal profile used for most RWC sources (see Figure 3-17) places more of the RWC emissions in
the morning and the evening when people are typically using these sources. This profile is based on a
2004 MANE-VU survey based temporal profiles.24 This profile was created by averaging three indoor and
three RWC outdoor temporal profiles from counties in Delaware and aggregating them into a single RWC
diurnal profile. This new profile was compared to a concentration-based analysis of aethalometer
measurements in Rochester, New York (Wang et al. 2011) for various seasons and days of the week and
was found that the new RWC profile generally tracked the concentration based temporal patterns.

Figure 3-17. RWC diurnal temporal profile

Comparison of RWC diurnal profile

0.12
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

The temporal allocation for "Outdoor Hydronic Heaters" (i.e., "OHH," SCC=2104008610) and "Outdoor
wood burning device, NEC (fire-pits, chimineas, etc.)" (i.e., "recreational RWC," SCC=21040087000) is
not based on temperature data, because the meteorologically-based temporal allocation used for the rest of
the rwc sector did not agree with observations for how these appliances are used.

For OHH, the annual-to-month, day-of-week and diurnal profiles were modified based on information in
the New York State Energy Research and Development Authority's (NYSERDA) "Environmental,

Energy Market, and Health Characterization of Wood-Fired Hydronic Heater Technologies, Final Report"
(NYSERDA, 2012), as well as a Northeast States for Coordinated Air Use Management (NESCAUM)
report "Assessment of Outdoor Wood-fired Boilers" (NESCAUM, 2006). A Minnesota 2008 Residential
Fuelwood Assessment Survey of individual household responses (MDNR, 2008) provided additional
annual-to-month, day-of-week, and diurnal activity information for OHH as well as recreational RWC
usage.

Data used to create the diurnal profile for OHH, shown in Figure 3-18, are based on a conventional single-
stage heat load unit burning red oak in Syracuse, New York. As shown in Figure 3-19, the NESCAUM
report describes how for individual units, OHH are highly variable day-to-day but that in the aggregate,
these emissions have no day-of-week variation. In contrast, the day-of-week profile for recreational RWC
follows a typical "recreational" profile with emissions peaked on weekends.

24 https://s3 .amazonaws.com/marama.org/wp-

content/uploads/2019/11/13093804/Qpen Burning Residential Areas Emissions Report-2004.pdf.

¦NEW
¦OLD

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Annual-to-month temporal allocation for OHH as well as recreational RWC were computed from the
MDNR 2008 survey and are illustrated in Figure 3-20. The OHH emissions still exhibit strong seasonal
variability, but do not drop to zero because many units operate year-round for water and pool heating. In
contrast to all other RWC appliances, recreational RWC emissions are used far more frequently during the
warm season.

Figure 3-18. Data used to produce a diurnal profile for OHH, based on heat load (BTU/hr)

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Figure 3-20. Annual-to-month temporal profiles for OHH and recreational RWC

3.3.5 Agricultural Ammonia Temporal Profiles (livestock)

For the agricultural livestock NFb algorithm, the GenTPRO algorithm is based on an equation derived by
Jesse Bash of the EPA's ORD based on the Zhu, Henze, et al. (2013) empirical equation. This equation is
based on observations from the Tropospheric Emissions Spectrometer (TES) satellite instrument with the
GEOS-Chem model and its adjoint to estimate diurnal NFb emission variations from livestock as a
function of ambient temperature, aerodynamic resistance, and wind speed. The equations are:

Et.h = [161500/T, /, x eM380 x AR,,/,	Equation 3-4

PE;,/; = Euh / Sum(E,,/,)	Equation 3-5

where

•	PE;,/; = Percentage of emissions in county i on hour h

•	Eij, = Emission rate in county i on hour h

•	Tin = Ambient temperature (Kelvin) in county i on hour h

•	AR;,/; = Aerodynamic resistance in county i

GenTPRO was run using the "BASH NH3" profile method to create month-to-hour temporal profiles for
these sources. Because these profiles distribute to the hour based on monthly emissions, the monthly
emissions are obtained from a monthly inventory, or from an annual inventory that has been temporalized
to the month. Figure 3-21 compares the daily emissions for Minnesota from the "old" approach (uniform
monthly profile) with the "new" approach (GenTPRO generated month-to-hour profiles) for 2014.

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Although the GenTPRO profiles show daily (and hourly variability), the monthly total emissions are the
same between the two approaches.

Figure 3-21. Example of animal NH3 emissions temporal allocation approach (daily total emissions)

2014fd Minnesota ag NH3 livestock daily temporal profiles

1600
1400
— 1200

;3 1000

1	800

-M

600

2	400

200 La

1/1/2014 2/1/2014 3/4/2014 4/4/2014 5/5/2014 6/5/2014 7/6/2014 S/6/2014 9/6/2014 10/7/201411/7/201412/8/2014

	month^ 	hourly

approach	approach

For the 2018 platform, the GenTPRO approach is applied to all sources in the livestock and fertilizer
sectors, NFb and non- NFb. Monthly profiles are based on the daily-based EPA livestock emissions from
the 2014 NEI. Profiles are by state/SCC_category, where SCC_category is one of the following: beef,
broilers, layers, dairy, swine.

3.3.6	Oil and gas temporal allocation (np_oilgas)

Monthly oil and gas temporal profiles by county and SCC were updated to use 2018 activity information
for the 2018 platform. Weekly and diurnal profiles are flat and are based on comments received on a
version of the 2011 platform.

3.3.7	Onroad mobile temporal allocation (onroad)

For the onroad sector, the temporal distribution of emissions is a combination of traditional temporal
profiles and the influence of meteorology. This section will discuss both the meteorological influences
and the development of the temporal profiles for this platform.

The "inventories" referred to in Table 3-19 consist of activity data for the onroad sector, not emissions.
For the off-network emissions from the rate-per-profile (RPP) and rate-per-vehicle (RPV) processes, the
VPOP activity data is annual and does not need temporal allocation. For rate-per-hour (RPH) processes
that result from hoteling of combination trucks, the HOTELING inventory is annual and was
temporalized to month, day of the week, and hour of the day through temporal profiles. Day-of-week and
hour-of-day temporal profiles are also used to temporalize the starts activity used for rate-per-start (RPS)
processes, and the off-network idling (ONI) hours activity used for rate-per-hour-ONI (RPHO) processes.
The inventories for starts and ONI activity contain monthly activity so that monthly temporal profiles are
not needed.

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For on-roadway rate-per-distance (RPD) processes, the VMT activity data is annual for some sources and
monthly for other sources, depending on the source of the data. Sources without monthly VMT were
temporalized from annual to month through temporal profiles. VMT was also temporalized from month to
day of the week, and then to hourly through temporal profiles. The RPD processes require a speed profile
(SPDPRO) that consists of vehicle speed by hour for a typical weekday and weekend day. For onroad, the
temporal profiles and SPDPRO will impact not only the distribution of emissions through time but also
the total emissions. Because SMOKE-MOVES (for RPD) calculates emissions based on the VMT, speed
and meteorology, if one shifted the VMT or speed to different hours, it would align with different
temperatures and hence different emission factors. In other words, two SMOKE-MOVES runs with
identical annual VMT, meteorology, and MOVES emission factors, will have different total emissions if
the temporal allocation of VMT changes. Figure 3-22 illustrates the temporal allocation of the onroad
activity data (i.e., VMT) and the pattern of the emissions that result after running SMOKE-MOVES. In
this figure, it can be seen that the meteorologically varying emission factors add variation on top of the
temporal allocation of the activity data.

Meteorology is not used in the development of the temporal profiles, but rather it impacts the calculation
of the hourly emissions through the program Movesmrg. The result is that the emissions vary at the
hourly level by grid cell. More specifically, the on-network (RPD) and the off-network parked vehicle
(RPV, RPH, RPHO, RPS, and RPP) processes use the gridded meteorology (MCIP) either directly or
indirectly. For RPD, RPV, RPS, RPH, and RPHO, Movesmrg determines the temperature for each hour
and grid cell and uses that information to select the appropriate emission factor for the specified
SCC/pollutant/mode combination. For RPP, instead of reading gridded hourly meteorology, Movesmrg
reads gridded daily minimum and maximum temperatures. The total of the emissions from the
combination of these six processes (RPD, RPV, RPH, RPHO, RPS, and RPP) comprise the onroad sector
emissions. The temporal patterns of emissions in the onroad sector are influenced by meteorology.

Figure 3-22. Example of temporal variability of NOx emissions

2014v2 onroad RPD hourly NOX and VMT: Wake County, NC

IAAMAaaH:!

7/8/140:00 7/9/140:00 7/10/140:00 7/11/140:00 7/12/140:00 7/13/140:00 7/14/140:00 7/15/140:00

Date and time (GMT)

New VMT day-of-week and hour-of-day temporal profiles were developed for use in the 2014NEIv2 and
later platforms as part of the effort to update the inputs to MOVES and SMOKE-MOVES under CRC A-
100 (Coordinating Research Council, 2017). CRC A-100 data includes profiles by region or county, road
type, and broad vehicle category. There are three vehicle categories: passenger vehicles (11/21/31),
commercial trucks (32/52), and combination trucks (53/61/62). CRC A-100 does not cover buses, refuse
trucks, or motor homes, so those vehicle types were mapped to other vehicle types for which CRC A-100
did provide profiles as follows: 1) Intercity/transit buses were mapped to commercial trucks; 2) Motor

120

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homes were mapped to passenger vehicles for day-of-week and commercial trucks for hour-of-day; 3)
School buses and refuse trucks were mapped to commercial trucks for hour-of-day and use a new custom
day-of-week profile called LOWSATSL'N that has a very low weekend allocation, since school buses and
refuse trucks operate primarily on business days. In addition to temporal profiles, CRC A-100 data were
also used to develop the average hourly speed data (SPDPRO) used by SMOKE-MOVES. In areas where
CRC A-100 data does not exist, hourly speed data is based on MOVES county databases.

The CRC A-100 dataset includes temporal profiles for individual counties, Metropolitan Statistical Areas
(MSAs), and entire regions (e.g., West, South). For counties without county or MSA temporal profiles
specific to itself, regional temporal profiles are used. Temporal profiles also vary by each of the MOVES
road types, and there are distinct hour-of-day profiles for each day of the week. Plots of hour-of-day
profiles for passenger vehicles in Fulton County, GA, are shown in Figure 3-23. Separate plots are shown
for Monday, Friday, Saturday, and Sunday, and each line corresponds to a particular MOVES road type
(i.e., road type 2 = rural restricted, 3 = rural unrestricted, 4 = urban restricted, and 5 = urban unrestricted).
Figure 3-24 shows which counties have temporal profiles specific to that county, and which counties use
MSA or regional average profiles. Figure 3-25 shows the regions used to compute regional average
profiles.

Monday

Figure 3-23. Sample onroad diurnal profiles for Fulton County, GA

Friday	Fulton Co

Fulton Co

passenger

passenger

5 6 7 8 9 10 11 12 13 14 15 16 17 IS 19 20 21 22 23 24
road 2	road 3	road 4	road 5

9 10 11 12 13 14 15 16 17 IS 19 20 21 22 23 24
—road 3	road 4	road 5

Saturday

Fulton Co

passenger

Sunday

Fulton Co

passenger

5 6 7 S 9 10 11 12 13 14 15 16 17 IS 19 20 21 22 23 24
road 2	road 3	road 4	road 5

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
road 2	road 3	road 4	road 5

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Figure 3-24. Methods to Populate On road Speeds and Temporal Profiles by Road Type

Road Type 2

Legend

~ MSA Boundary {outlined in black)
| Individual

| MSA average of non-Core Counties
Region Average of MSA Core Counties
Region Average of MSA non-Core Counties
| Region Average of non-MSA Counties

Road Type 4

Legend

~ MSA Boundary (outlined in black)
| Individual

| MSA average of non-Core Counties
m Region Average of MSA Core Counties

	! Region Average of MSA non-Core Counties

| Region Average of non-MSA Counties

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Figure 3-24 Methods to Populate Onroad Speeds and Temporal Profiles by Road Type (ctd).

Legend

| MSA Boundary (outlined in black)
J Individual

| MSA average of non-Core Counties
^ Region Average of MSA Core Counties
_ Region Average of MSA non-Core Counties
| Region Average of non-MSA Counties

Road Type 3

Legend

MSA Boundary (outlined in black)
| Individual

^ MSA average of non-Core Counties
Region Average of MSA Core Counties
Region Average of MSA non-Core Counties
B Region Average of non-MSA Counties

Road Type 5

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Figure 3-25. Regions for computing Region Average Speeds and Temporal Profiles

For hoteling, day-of-week profiles are the same as non-hoteling for combination trucks, while hour-of-day
non-hoteling profiles for combination trucks were inverted to create new hoteling profiles that peak
overnight instead of during the day. The combination truck profiles for Fulton County are shown in
Figure 3-26.

Temporal profiles for RPHO are based on the same temporal profiles as the on-network processes in
RPD, but since the on-network profiles are road-type-specific and ONI is not road-type-specific, the
RPHO profiles were assigned to use rural unrestricted profiles for counties considered "rural" and urban
unrestricted profiles for counties considered "urban." RPS uses a separate set of temporal profiles
specifically for starts activity. For starts, there is one day-of-week temporal profile for each source type
(e.g., motorcycles, passenger cars, combination long haul trucks), and two hour-of-day temporal profiles
for each source type, one for weekdays and one for weekends. The temporal profiles for starts are applied
nationally and are based on the default starts-per-day-per-vehicle and starts-hour-fraction tables from
MOWS.

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Monday

0.08
0.07

0.06
0.05
0.04
0.03
0.02
0.01
0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
road 2	road 3	road 4	road 5

0.06
0.05
0.04
0.03
0.02
0.01
0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
road 2	road 3	road 4	road 5

Figure 3-26. Example of Temporal Profiles for Combination Trucks
Fulton Co	combo	Friday	Fulton Co

0.08
0.07

combo

Saturday	Fulton Co	combo

0.08

Sunday	Fulton Co	combo

0.07

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
road 2	road 3	road 4	road 5

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
road 2	road 3	road 4	road 5

3.3.8 Nonroad mobile temporal allocation(nonroad)

For nonroad mobile sources, temporal allocation is performed differently for different SCCs. Beginning
with the final 2011 platform and continuing into this platform, some improvements to temporal allocation
of nonroad mobile sources were made to make the temporal profiles more realistically reflect real-world
practices. Some specific updates were made for agricultural sources (e.g., tractors), construction, and
commercial residential lawn and garden sources.

Figure 3-27 shows two previously use temporal profiles (9 and 18) and the updated temporal profile (19)
that has lower emissions on weekends. In this platform, construction and commercial lawn and garden
sources use profile 19. Residental lawn and garden sources use profile 9 and agricultural sources use
profile 19.

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Figure 3-27. Example Nonroad Day-of-week Temporal Profiles

Day of Week Profiles

0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0

monday tuesday Wednesday thursday friday saurday sundae

Figure 3-28 shows the previously existing temporal profiles 26 and 27 along with the temporal profiles
(25a and 26a) that have lower emissions overnight. In this platform, construction sources use profile 26a.
Commercial lawn and garden and agriculture sources use the profiles 26a and 25a, respectively.

Residental lawn and garden sources use profile 27.

Figure 3-28. Example Nonroad Diurnal Temporal Profiles

Hour of Day Profiles

0.11

o.i
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0

hi h2 h3 h4 h5 to6 h7 h8 h9 hl0hllhl2hl3hl4hl5hl6hl7hlShl9h20h21h22h23h24
26a-New 	27 	25 a-New 	26

3.3.9 Additional sector specific details (afdust, beis, cmv, rail, nonpt,
ptnonipm, ptfire)

For the afdust sector, meteorology is not used in the development of the temporal profiles, but it is used to
reduce the total emissions based on meteorological conditions. These adjustments are applied through
sector-specific scripts, beginning with the application of land use-based gridded transport fractions and

126

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then subsequent zero-outs for hours during which precipitation occurs or there is snow cover on the
ground. The land use data used to reduce the NEI emissions explains the amount of emissions that are
subject to transport. This methodology is discussed in (Pouliot et al., 2010), and in "Fugitive Dust
Modeling for the 2008 Emissions Modeling Platform" (Adelman, 2012). The precipitation adjustment is
applied to remove all emissions for hours where measurable rain occurs, or where there is snow cover.
Therefore, the afdust emissions vary day-to-day based on the precipitation and/or snow cover for each
grid cell and hour. Both the transport fraction and meteorological adjustments are based on the gridded
resolution of the platform; therefore, somewhat different emissions will result from different grid
resolutions. For this reason, to ensure consistency between grid resolutions, afdust emissions for the
36US3 grid are aggregated from the 12US1 emissions. Application of the transport fraction and
meteorological adjustments prevents the overestimation of fugitive dust impacts in the grid modeling as
compared to ambient samples.

Biogenic emissions in the beis sector vary by every hour of the year because they are developed using
meteorological data including temperature, surface pressure, and radiation/cloud data. The emissions are
computed using appropriate emission factors according to the vegetation in each model grid cell, while
taking the meteorological data into account.

For the nonroad sector, while the NEI only stores the annual totals, the modeling platform uses monthly
inventories from output from MOVES. For California, CARB's annual inventory was temporalized to
monthly using monthly temporal profiles applied in SMOKE by SCC.

For the cmv sectors, most areas use hourly emission inventories derived from the 5-minute AIS data. In
some areas where AIS data are not available, such as in Canada between the St. Lawrence Seaway and the
Great Lakes and in the southern Caribbean, the flat temporal profiles are used for hourly and day-of-week
values. Most regions without AIS data also use a flat monthly profile, with some offshore areas using an
average monthly profile derived from the 2008 ECA inventory monthly values. These areas without AIS
data also use flat day of week and hour of day profiles.

For the rail sector, new monthly profiles were developed for the 2016 platform and continue to be used in
this platform. Monthly temporal allocation for rail freight emissions is based on AAR Rail Traffic Data,
Total Carloads and Intermodal, for 2016. For passenger trains, monthly temporal allocation is flat for all
months. Rail passenger miles data is available by month for 2016 but it is not known how closely rail
emissions track with passenger activity since passenger trains run on a fixed schedule regardless of how
many passengers are aboard, and so a flat profile is used for passenger trains. Rail emissions are allocated
with flat day of week profiles, and most emissions are allocated with flat hourly profiles.

For the ptagfire sector, the inventories are in the daily point fire format FF10 PTDAY. The diurnal
temporal profile for ag fires reflects the fact that burning occurs during the daylight hours - see Figure
3-29 (McCarty et al., 2009). This puts most of the emissions during the workday and suppresses the
emissions during the middle of the night.

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Figure 3-29. Agricultural burning diurnal temporal profile

Comparison of Agricultural Burning Temporal Profiles

Industrial processes that are not likely to shut down on Sundays, such as those at cement plants, use
profiles that include emissions on Sundays, while those that would shut down on Sundays use profiles that
reflect Sunday shutdowns.

For the ptfire sectors, the inventories are in the daily point fire format FF10 PTDAY. Separate hourly
profiles for prescribed and wildfires were used. Figure 3-30 shows the profiles used for each state for the
2018gc and 2018v2 modeling platforms. The wildfire diurnal profiles are similar but vary according to the
average meteorological conditions in each state. The 2018gc and 2018v2 platforms used diurnal profiles
for prescribed profile that better reflect flaming and residual smoldering phases and average burn
practices. These flaming and residual smoldering diurnal profiles vary slightly by region.

Figure 3-30. Prescribed and Wildfire diurnal temporal profiles

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3.4 Spatial Allocation

The methods used to perform spatial allocation are summarized in this section. The spatial factors are
typically applied by SCC to allocate emissions from a county or province-based emissions inventory to
specific grid cells. They are not used for point source data since those usually have specific locations
assigned. If a particular spatial dataset used to develop a spatial surrogate does not have data for all
counties (or provinces) for which there could be emissions assigned to use that surrogate, data are added
to the surrogate from other more comprehensive surrogates to ensure that emissions data are not lost when
the spatial surrogate is applied. Through gap-filling, data for entire counties or provinces are pulled from a
secondary or tertiary surrogate into the primary surrogate so that the gap-filled surrogate has entries for all
counties that may have a particular type of emissions.

As described in Section 3.1, spatial allocation was performed for national 36-km and 12-km domains. To
accomplish this, SMOKE used national 36-km and 12-km spatial surrogates and a SMOKE area-to-point
data file. For the U.S., the spatial surrogates are based on circa 2017 to 2018 data wherever possible. For
Mexico, the spatial surrogates used as described below. For Canada, surrogates were provided by ECCC
for the 2016v7.2 (beta) platform and those continue to be used in this platform. The U.S., Mexican, and
Canadian 36-km and 12-km surrogates cover the entire CONUS domain 12US1 shown in Figure 3-1. The
36US3 domain includes a portion of Alaska, thus special considerations are taken to include Alaska
emissions in 36-km modeling.

2018v2 platform uses the same surrogates and surrogate assignments as the 2016v3 platform, which were
essentially the same as those used for the 2016v2 platform. Documentation of the origin of the spatial
surrogates for the platform is provided in the 2018v2 surrogate specifications workbook. The remainder
of this subsection summarizes the data used for the spatial surrogates and the area-to-point data which is
used for airport refueling.

3.4.1 Spatial Surrogates for U.S. emissions

There are more than 80 spatial surrogates available for spatially allocating U.S. county-level emissions to
the 36-km and 12-km grid cells used by the air quality model. Spatial surrogates are typically developed
based on nationally available data sources (e.g., census data, national land cover database). An exception
is when a regional inventory is used (e.g., the WRAP oil and gas inventory) and regional surrogates are
used in association with that inventory. As described in Section 3.4.2, an area-to-point approach overrides
the use of surrogates for airport refueling sources. Table 3-20 lists the codes and descriptions of the spatial
surrogates. In this table, surrogate names and codes listed in italics are not directly assigned to any
sources for this platform, but they may be used to gapfill other surrogates. The WRAP oil and gas
surrogates used in this platform are not listed in Table 3-20 but are instead listed in Table 3-22.

Many surrogates were updated or newly developed for use in the 2014v7.0 platform (Adelman, 2016).
They include the use of the 2011 National Land Cover Database (the previous platform used 2006) and
development of various development density levels such as open, low, medium high and various
combinations of these. These NLCD-based surrogates largely replaced the FEMA category (500 series)
surrogates that were used in the 2011 platform. Additionally, onroad surrogates were developed using
average annual daily traffic counts from the highway monitoring performance system (HPMS).

Previously, the "activity" for the onroad surrogates was length of road miles. These and other surrogates
are described in a reference (Adelman, 2016).

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Issues were identified in the rail surrogates 261 and 271 that caused emissions to be allocated to cells far
from the county. Comparisons were made in which county-cell mappings from all surrogates, were
compared with the land area surrogate, and looked for county-cells that were two or more 36km cells
away from the nearest cell for each county in the land area surrogate. Several problem cells were
identified in 261 and 271. Therefore surrogates 261 and 271 were edited by removing the problem county-
cells, and renormalizing the remaining factors so they sum to one.

Some surrogates were updated or newly developed for this platform or for the 2016 platforms:
oil and gas surrogates represent activity during the year 2018;

onroad spatial allocation uses surrogates that do not distinguish between urban and rural road
types, correcting the issue arising in some counties due to the inconsistent urban and rural
definitions between MOVES, the activity data, and the surrogate data, and were further updated
for the 2016 platform;

spatial surrogates for on-roadway sources use annual average daily traffic (AADT) for 2017;

-	the surrogate used for truck stops was updated in 2019;

a public schools surrogate (#508) was added in the 2016v2 platform;

surrogate 508: "Public Schools" from 2018-2019 NCES public school was developed and is
assigned to school buses;

surrogate 259, used for transit bus off-network (onroad), was re-gapfilled using 306 (NLCD
Med+High) first and population second - this addressed the overallocation to rural areas noted
with the prior gapfilling approach;

surrogate 306 (NLCD Med+High) now used in place of 259 since intercity bus is now other bus;

-	the use of 500 series surrogates (except for the new #508) were phased out;
rail surrogates 261 and 271 were updated to fix some misallocated emissions;
surrogate 535 was reassigned to 307 (NLCD All Development); and
surrogate 505 was reassigned to 306 (NLCD Med+High).

The surrogates for the U.S. were mostly generated using the Surrogate Tools DB tool, although a few
were developed using the Spatial Allocator. The tool and documentation for the Surrogate Tools DB is
available at https://www.cmascenter.org/surrogate tools db/.

Table 3-20. U.S. Surrogates available for this modeling platforms

Code

Surrogate Description

Code

Surrogate Description

N/A

Area-to-point approach (see 3.6.2)

318

NLCD Pasture Land

100

Population

319

NLCD Crop Land

110

Housing

320

NLCD Forest Land

131

urban Housing

321

NLCD Recreational Land

132

Suburban Housing

340

NLCD Land

134

Rural Housing

350

NLCD Water

137

Housing Change \

508

Public Schools

140

Housing Change and Population

650

Refineries and Tank Farms

150

Residential Heating - Natural Gas

670

Spud Count - CBM Wells

160

Residential Heating - Wood

671

Spud Count - Gas Wells

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Code

Surrogate Description

Code

Surrogate Description

170

Residential Heating - Distillate Oil

672

Gas Production at Oil Wells

180

Residential Heating - Coal

673

Oil Production at CBM Wells

190

Residential Heating - LP Gas

674

Unconventional Well Completion Counts

201

Urban Restricted Road Miles

676

Well Count - All Producing

202

Urban Restricted AADT

677

Well Count-All Exploratory

205

Extended Idle Locations

678

Completions at Gas Wells

211

Rural Restricted Road Miles

679

Completions at CBM Wells

212

Rural Restricted AADT

681

Spud Count - Oil Wells

221

Urban Unrestricted Road Miles

683

Produced Water at All Wells

222

Urban Unrestricted AADT

6831

Produced water at CBM wells

231

Rural Unrestricted Road Miles \

6832

Produced water at gas wells

232

Rural Unrestricted AADT I

6833

Produced water at oil wells

239

Total Road AADT

685

Completions at Oil Wells

240

Total Road Miles

686

Completions at All Wells

241

Total Restricted Road Miles

687

Feet Drilled at All Wells

242

All Restricted AADT

689

Gas Produced - Total

243

Total Unrestricted Road Miles

691

Well Counts - CBM Wells

244

All Unrestricted AADT

692

Spud Count-All Wells

258

Intercity Bus Terminals

693

Well Count - All Wells

259

Transit Bus Terminals

694

Oil Production at Oil Wells

260

Total Railroad Miles j

695

Well Count - Oil Wells

261

NT AD Total Railroad Density

696

Gas Production at Gas Wells

271

NT AD Class 12 3 Railroad Density

697

Oil Production at Gas Wells

272

NTAD Amtrak Railroad Density

698

Well Count - Gas Wells

273

NTAD Commuter Railroad Density

699

Gas Production at CBM Wells

275

ERTACRail Yards

710

Airport Points

280

Class 2 and 3 Railroad Miles \

711

Airport Areas

300

NLCD Low Intensity Development

801

Port Areas

301

NLCD Med Intensity Development

802

Shipping Lanes

302

NLCD High Intensity Development

805

Offshore Shipping Area

303

NLCD Open Space ;

806

Offshore Shipping NEI2014 Activity

304

NLCD Open + Low

807

Navigable Waterway Miles

305

NLCD Low + Med

808

2013 Shipping Density

306

NLCD Med + High

820

Ports NEI2014 Activity

307

NLCD All Development

850

Golf Courses

308

NLCD Low + Med + High

860

Mines

309

NLCD Open + Low + Med

890

Commercial Timber

310

NLCD Total Agriculture





For the onroad sector, the on-network (RPD) emissions were spatially allocated differently from other off-
network processes (e.g., RPV, RPP, RPHO). Surrogates for on-network processes are based on AADT
data and off network processes (including the off-network idling included in RPHO) are based on land use
surrogates as shown in Table 3-21. Emissions from the extended (i.e., overnight) idling of trucks were
assigned to surrogate 205, which is based on locations of overnight truck parking spaces. The underlying
data for this surrogate were updated during the development of the 2016 platforms to include additional
data sources and corrections based on comments received and those updates were carried into this
platform.

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Table 3-21. Off-Network Mobile Source Surrogates

Source type

Source Type name

Surrogate ID

Description

11

Motorcycle

307

NLCD All Development

21

Passenger Car

307

NLCD All Development

31

Passenger Truck

307

NLCD All Development







NLCD Low + Med +

32

Light Commercial Truck

308

High

41

Other Bus

306

NLCD Med + High

42

Transit Bus

259

Transit Bus Terminals

43

School Bus

508

Public Schools

51

Refuse Truck

306

NLCD Med + High

52

Single Unit Short-haul Truck

306

NLCD Med + High

53

Single Unit Long-haul Truck

306

NLCD Med + High

54

Motor Home

304

NLCD Open + Low

61

Combination Short-haul Truck

306

NLCD Med + High

62

Combination Long-haul Truck

306

NLCD Med + High

For the oil and gas sources in the np oilgas sector, the spatial surrogates were updated to those shown in
Table 3-22 using 2018 data consistent with what was used to develop the 2018gc nonpoint oil and gas
emissions. The exception was the use of WRAP spatial surrogates from 2016v2 platform for production
in New Mexico and North Dakota. The primary activity data source used for the development of the oil
and gas spatial surrogates was data from Drilling Info (DI) Desktop's HPDI database (Drilling Info,
2019). This database contains well-level location, production, and exploration statistics at the monthly
level. Due to a proprietary agreement with DI Desktop, individual well locations and ancillary
production cannot be made publicly available, but aggregated statistics are allowed. These data were
supplemented with data from state Oil and Gas Commission (OGC) websites (Alaska, Arizona, Idaho,
Illinois, Indiana, Kentucky, Louisiana, Michigan, Mississippi, Missouri, Nevada, Oregon and
Pennsylvania, Tennessee). In cases when the desired surrogate parameter was not available (e.g., feet
drilled), data for an alternative surrogate parameter (e.g., number of spudded wells) was downloaded and
used. Under that methodology, both completion date and date of first production from HPDI were used to
identify wells completed during 2018. In total, over 1 million unique wells were compiled from the above
data sources (ERG, 2021). The wells cover 34 states and over 1,100 counties.

Table 3-22. Spatial Surrogates for Oil and Gas Sources

Surrogate Code

Surrogate Description

670

Spud Count - CBM Wells

671

Spud Count - Gas Wells

672

Gas Production at Oil Wells

673

Oil Production at CBM Wells

674

Unconventional Well Completion Counts

676

Well Count - All Producing

677

Well Count - All Exploratory

678

Completions at Gas Wells

679

Completions at CBM Wells

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Surrogate Code

Surrogate Description

681

Spud Count - Oil Wells

683

Produced Water at All Wells

685

Completions at Oil Wells

686

Completions at All Wells

687

Feet Drilled at All Wells

689

Gas Produced - Total

691

Well Counts - CBM Wells

692

Spud Count - All Wells

693

Well Count - All Wells

694

Oil Production at Oil Wells

695

Well Count - Oil Wells

696

Gas Production at Gas Wells

697

Oil Production at Gas Wells

698

Well Count - Gas Wells

699

Gas Production at CBM Wells

2688

WRAP Gas production at oil wells

2689

WRAP Gas production at all wells

2691

WRAP Well count - CBM wells

2693

WRAP Well count - all wells

2694

WRAP Oil production at oil wells

2695

WRAP Well count - oil wells

2696

WRAP Gas production at gas wells

2697

WRAP Oil production at gas wells

2698

WRAP Well count - gas wells

2699

WRAP Gas production at CBM wells

6831

Produced water at CBM wells

6832

Produced water at gas wells

6833

Produced water at oil wells

Not all of the available surrogates are used to spatially allocate sources in the modeling platform; that is,
some surrogates shown in Table 3-20 were not assigned to any SCCs, although many of the "unused"
surrogates are actually used to "gap fill" primary surrogates, as discussed above. Table 3-23 shows the
CAP emissions (i.e., NH3, NOx, PM2.5, SO2, and VOC) by sector assigned to each spatial surrogate.

For 36US3 modeling in this platform, most U.S. emissions sectors were processed using 36-km spatial
surrogates, and if applicable, 36-km meteorology. Exceptions include:

- For the onroad and onroad ca adj sectors, instead of running SMOKE-MOVES with 36km

meteorological data, 36US3 emissions were aggregated from 12US1 by summing emissions from
a 3x3 group of 12-km cells into a single 36-km cell. Differences in the 12-km and 36-km
meteorology can introduce differences in onroad emissions, so this approach ensures that the 36-
km and 12-km onroad emissions are consistent. However, this approach means that 36US3 onroad

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does not include emissions in Southeast Alaska; therefore, Alaska onroad emissions are included
in a separate sector called onroadnonconus that is processed for only the 36US3 domain. The
36US3 onroad nonconus emissions are spatially allocated using 36-km surrogates and processed
with 36-km meteorology.

Similarly to onroad, because afdust emissions incorporate meteorologically-based adjustments,
afdust adj emissions for 36US3 were aggregated from 12US1 to ensure consistency in emissions
between modeling domains. Again, similarly to onroad, this means 36US3 afdust does not include
emissions in Southeast Alaska; therefore, Alaska afdust emissions are processed in a separate
sector called afdustakadj. The 36US3 afdustakadj emissions are spatially allocated using 36-
km surrogates and adjusted with 36-km meteorology.

The ag and rwc sectors are processed using 36-km spatial surrogates, but using temporal profiles
based on 12-km meteorology.

Table 3-23. Selected 2018 CAP emissions by sector for U.S. Surrogates (short tons in 12US1)

Sector

ID

Description

NH3

NOX

PM2 5

S02

voc

Afdust

240

Total Road Miles

0

0

312,090

0

0

Afdust

304

NLCD Open + Low

0

0

842,116

0

0

Afdust

306

NLCD Med + High

0

0

52,278

0

0

Afdust

308

NLCD Low + Med + High

0

0

117,047

0

0

Afdust

310

NLCD Total Agriculture

0

0

791,881

0

0

fertilizer

310

NLCD Total Agriculture

1,636,229

0

0

0

0

livestock

310

NLCD Total Agriculture

2,582,189

0

0

0

226,398

Nonpt

100

Population

34,304

0

0

0

208

Nonpt

150

Residential Heating - Natural Gas

33,550

204,371

4,041

1,365

12,055

Nonpt

170

Residential Heating - Distillate Oil

1,531

30,031

3,284

11,510

1,039

Nonpt

180

Residential Heating - Coal

1

3

1

3

3

Nonpt

190

Residential Heating - LP Gas

98

31,061

163

712

1,181

Nonpt

239

Total Road AADT

0

22

541

0

297,798

Nonpt

244

All Unrestricted AADT

0

0

0

0

101,255

Nonpt

271

NTAD Class 12 3 Railroad Density

0

0

0

0

2,203

Nonpt

300

NLCD Low Intensity Development

4,823

19,093

94,548

2,882

72,599

Nonpt

304

NLCD Open + Low

0

0

0

0

0

Nonpt

306

NLCD Med + High

23,668

272,514

245,871

131,592

112,049

Nonpt

307

NLCD All Development

85

25,798

110,610

8,169

69,262

Nonpt

308

NLCD Low + Med + High

884

156,033

15,683

10,076

10,037

Nonpt

310

NLCD Total Agriculture

0

0

38

0

0

Nonpt

319

NLCD Crop Land

0

0

97

72

299

Nonpt

320

NLCD Forest Land

3,953

68

273

0

279

Nonpt

650

Refineries and Tank Farms

0

16

0

0

106,401

Nonpt

711

Airport Areas

0

0

0

0

596

Nonpt

801

Port Areas

0

0

0

0

6,730

Nonroad

261

NTAD Total Railroad Density

3

1,914

198

1

376

nonroad

304

NLCD Open + Low

4

1,690

144

4

2,488

nonroad

305

NLCD Low + Med

95

14,943

3,859

104

106,139

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Sector

ID

Description

NH3

NOX

PM2 5

S02

voc

nonroad

306

NLCD Med + High

326

166,683

10,459

297

89,752

nonroad

307

NLCD All Development

101

29,905

15,389

97

170,454

nonroad

308

NLCD Low + Med + High

551

286,527

23,894

234

47,904

nonroad

309

NLCD Open + Low + Med

121

21,137

1,246

135

45,692

nonroad

310

NLCD Total Agriculture

420

329,678

23,876

187

34,856

nonroad

320

NLCD Forest Land

15

3,954

558

8

3,731

nonroad

321

NLCD Recreational Land

83

12,636

5,805

76

215,471

nonroad

350

NLCD Water

191

114,414

4,918

212

293,014

nonroad

850

Golf Courses

13

2,066

118

14

5,685

nonroad

860

Mines

2

2,523

251

1

476

np oilgas

670

Spud Count - CBM Wells

0

0

0

0

183

np oilgas

671

Spud Count - Gas Wells

0

0

0

0

6,021

np oilgas

674

Unconventional Well Completion
Counts

31

25,368

618

30

1,110

np oilgas

678

Completions at Gas Wells

0

9,892

254

3,674

37,861

np oilgas

679

Completions at CBM Wells

0

5

0

237

700

np oilgas

681

Spud Count - Oil Wells

0

0

0

0

46,149

np oilgas

683

Produced Water at All Wells

0

22

0

0

868

np oilgas

685

Completions at Oil Wells

0

438

0

2,026

57,876

np oilgas

687

Feet Drilled at All Wells

0

84,073

2,261

115

3,834

np oilgas

689

Gas Produced - Total

0

569

28

2

32,663

np oilgas

691

Well Counts - CBM Wells

0

12,025

222

5

16,035

np oilgas

692

Spud Count - All Wells

0

365

12

42

34

np oilgas

693

Well Count - All Wells

0

0

0

0

2

np oilgas

694

Oil Production at Oil Wells

0

2,607

0

1,651

477,995

np oilgas

695

Well Count - Oil Wells

0

137,335

3,239

19,295

435,954

np oilgas

696

Gas Production at Gas Wells

0

40,240

0

4,249

235,302

np oilgas

697

Oil Production at Gas Wells

0

858

0

0

80,817

np oilgas

698

Well Count - Gas Wells

7

277,705

3,918

141

444,273

np oilgas

699

Gas Production at CBM Wells

0

29

5

0

3,531

np oilgas

2688

WRAP Gas production at oil wells

0

7,188

0

5,435

206,000

np oilgas

2689

WRAP Gas production at all wells

0

25,667

772

1,108

19,346

np oilgas

2691

WRAP Well count - CBM wells

0

190

15

0

1,269

np oilgas

2693

WRAP Well count - all wells

0

84

3

0

5

np oilgas

2694

WRAP Oil production at oil wells

0

31,299

446

17,337

70,025

np oilgas

2695

WRAP Well count - oil wells

0

1,233

124

4

55,343

np oilgas

2696

WRAP Gas production at gas wells

0

1,424

19

1

22,763

np oilgas

2697

WRAP Oil production at gas wells

0

29

0

0

10,273

np oilgas

2698

WRAP Well count - gas wells

0

728

56

0

49,283

np oilgas

2699

WRAP Gas production at CBM wells

0

9,026

268

8

6,984

np oilgas

6831

Produced water at CBM wells

0

0

0

0

740

np oilgas

6832

Produced water at gas wells

0

0

0

0

16,231

np oilgas

6833

Produced water at oil wells

0

0

0

0

74,707

135


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Sector

ID

Description

NH3

NOX

PM2 5

S02

voc

np solvents

100

Population

0

0

0

0

1,354,437

np solvents

240

Total Road Miles

0

0

0

0

50,500

np solvents

306

NLCD Med + High

33

27

300

1

395,102

np solvents

307

NLCD All Development

24

6

19

5

365,628

np solvents

308

NLCD Low + Med + High

0

0

129

0

8,324

np solvents

310

NLCD Total Agriculture

0

0

0

0

162,850

onroad

205

Extended Idle Locations

333

31,740

616

17

3,337

onroad

242

All Restricted AADT

34,519

922,998

23,496

6,667

137,657

onroad

244

All Unrestricted AADT

63,741

1,538,528

53,194

14,424

387,798

onroad

259

Transit Bus Terminals

15

2,725

63

2

510

onroad

304

NLCD Open + Low

0

872

27

0

6,880

onroad

306

NLCD Med + High

927

94,894

3,461

86

19,921

Onroad

307

NLCD All Development

3,494

211,798

6,822

1,352

584,337

Onroad

308

NLCD Low + Med + High

206

21,756

549

78

31,605

Onroad

508

Public Schools

15

2,140

85

1

562

Rail

261

NT AD Total Railroad Density

15

35,364

988

32

1,704

Rail

271

NTAD Class 12 3 Railroad Density

350

535,605

14,016

695

23,244

Rwc

300

NLCD Low Intensity Development

16,143

34,093

299,278

7,988

323,969

3.4.2	Allocation method for airport-related sources in the U.S.

There are numerous airport-related emission sources in the NEI, such as aircraft, airport ground support
equipment, and jet refueling. The modeling platform includes the aircraft and airport ground support
equipment emissions as point sources. For the modeling platform, the EPA used the SMOKE "area-to-
point" approach for only jet refueling in the nonpt sector. The following SCCs use this approach:
2501080050 and 2501080100 (petroleum storage at airports), and 2810040000 (aircraft/rocket engine
firing and testing). The ARTOPNT approach is described in detail in the 2002 platform documentation:
https://www.epa.gov/sites/default/files/2020-10/documents/emissions tsd voll 02-28-08.pdf. The
ARTOPNT file that lists the nonpoint sources to locate using point data were unchanged from the 2005-
based platform.

3.4.3	Surrogates for Canada and Mexico emission inventories

Spatial surrogates for allocating Mexico municipio level emissions were updated in the 2014v7.1 platform
and carried forward into this platform. For the 2016 beta (v7.2) platform, a set of Canada shapefiles were
provided by ECCC along with cross references to spatially allocate the year 2015 Canadian emissions.
Gridded surrogates were generated using the Surrogate Tool (previously referenced); Table 3-24 provides
a list. For computational reasons, total roads (1263) were used instead of the unpaved rural road surrogate
provided. The population surrogate for Mexico; surrogate code 11, uses 2015 population data at 1 km
resolution and replaced the previous population surrogate code 10. The other surrogates for Mexico are
circa 1999 and 2000 and were based on data obtained from the Sistema Municipal de Bases de Datos
(SIMBAD) de INEGI and the Bases de datos del Censo Economico 1999. Most of the CAPs allocated to
the Mexico and Canada surrogates are shown in Table 3-25.

136


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Table 3-24. Canadian Spatial Surrogates

Code

Canadian Surrogate Description

Code

Description







TOTAL INSTITUTIONAL AND

100

Population

923

GOVERNEMNT

101

total dwelling

924

Primary Industry

104

capped total dwelling

925

Manufacturing and Assembly

106

ALL INDUST

926

Distribution and Retail (no petroleum)

113

Forestry and logging

927

Commercial Services

200

Urban Primary Road Miles

932

CANRAIL

210

Rural Primary Road Miles

940

PAVED ROADS NEW

211

Oil and Gas Extraction

945

Commercial Marine Vessels

212

Mining except oil and gas

946

Construction and mining

220

Urban Secondary Road Miles

948

Forest

221

Total Mining

951

Wood Consumption Percentage

222

Utilities

955

UNPAVED ROADS AND TRAILS

230

Rural Secondary Road Miles

960

TOTBEEF

233

Total Land Development

970

TOTPOUL

240

capped population

980

TOTS WIN

308

Food manufacturing

990

TOTFERT

321

Wood product manufacturing

996

urban area

323

Printing and related support activities

1251

OFFR TOTFERT

324

Petroleum and coal products manufacturing

1252

OFFR MINES

326

Plastics and rubber products manufacturing

1253

OFFR Other Construction not Urban

327

Non-metallic mineral product manufacturing

1254

OFFR Commercial Services

331

Primary Metal Manufacturing

1255

OFFR Oil Sands Mines

350

Water

1256

OFFR Wood industries CANVEC

412

Petroleum product wholesaler-distributors

1257

OFFR UNPAVED ROADS RURAL

448

clothing and clothing accessories stores

1258

OFFR Utilities

482

Rail transportation

1259

OFFR total dwelling

562

Waste management and remediation services

1260

OFFR water

901

AIRPORT

1261

OFFR ALL INDUST

902

Military LTO

1262

OFFR Oil and Gas Extraction

903

Commercial LTO

1263

OFFR ALLROADS

904

General Aviation LTO

1265

OFFR CANRAIL

921

Commercial Fuel Combustion

9450

Commercial Marine Vessel Ports

Table 3-25. CAPs Allocated to Mexican and Canadian Spatial Surrogates (short tons in 36US3)

Sector

Code

Mexican / Canadian Surrogate Description

NH3

NOx

pm25

so2

voc

othafdust

106

CAN ALL INDUST

0

0

609

0

0

othafdust

212

CAN Mining except oil and gas

0

0

3,142

0

0

othafdust

221

CAN Total Mining

0

0

17,315

0

0

othafdust

222

CAN Utilities

0

0

2,792

0

0

othafdust

940

CAN Paved Roads New

0

0

29,862

0

0

137


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Sector

Code

Mexican / Canadian Surrogate Description

nh3

NOx

pm25

so2

voc

othafdust

955

CAN UNPAVEDROADSANDTRAILS

0

0

426,511

0

0

othar

11

MEX 2015 Population

0

0

0

0

628,869

othar

14

MEX Residential Heating - Wood

251

44,151

121,868

3,765

327,369

othar

16

MEX Residential Heating - Distillate Oil

4

121

0

0

5

othar

22

MEX Total Road Miles

1

236

5,247

1

5,900

othar

24

MEX Total Railroad Miles

0

53,191

1,141

492

2,003

othar

26

MEX Total Agriculture

573,834

74,104

47,068

1,866

16,648

othar

32

MEX Commercial Land

0

387

8,290

0

100,237

othar

34

MEX Industrial Land

176

4,104

4,022

13

100,682

othar

36

MEX Commercial plus Industrial Land

7

22,388

1,365

15

229,263

othar

40

MEX Residential (RES1-

4)+Comercial+Industrial+Institutional+Governme

nt

4

87

373

14

102,973

othar

42

MEX Personal Repair (COM3)

0

0

0

0

25,438

othar

44

MEX Airports Area

0

14,556

186

1,111

5,970

othar

48

MEX Brick Kilns

0

2,752

54,113

4,952

1,322

othar

50

MEX Mobile sources - Border Crossing

3

63

2

0

50

othar

100

CAN Population

795

52

622

15

225

othar

101

CAN total dwelling

0

0

0

0

151,094

othar

104

CAN Capped Total Dwelling

361

31,746

2,335

2,671

1,650

othar

113

CAN Forestry and logging

152

1,818

9,778

37

5,140

othar

211

CAN Oil and Gas Extraction

1

43

433

74

2,122

othar

212

CAN Mining except oil and gas

0

0

11

0

0

othar

221

CAN Total Mining

0

0

293

0

0

othar

222

CAN Utilities

57

3,439

166

464

65

othar

308

CAN Food manufacturing

0

0

19,253

0

17,468

othar

321

CAN Wood product manufacturing

873

4,822

1,646

383

16,605

othar

323

CAN Printing and related support activities

0

0

0

0

11,778

othar

324

CAN Petroleum and coal products manufacturing

0

1,201

1,632

467

9,368

othar

326

CAN Plastics and rubber products manufacturing

0

0

0

0

24,270

othar

327

CAN Non-metallic mineral product manufacturing

0

0

6,541

0

0

othar

331

CAN Primary Metal Manufacturing

0

158

5,598

30

72

othar

412

CAN Petroleum product wholesaler-distributors

0

0

0

0

45,634

othar

448

CAN clothing and clothing accessories stores

0

0

0

0

143

othar

482

CAN Rail Transportation

1

4,106

89

1

258

othar

562

CAN Waste management and remediation services

247

1,981

2,747

2,508

9,654

othar

901

CAN Airport

0

108

10

0

11

othar

921

CAN Commercial Fuel Combustion

206

24,819

2,435

1,669

1,254

othar

923

CAN TOTAL INSTITUTIONAL AND
GOVERNEMNT

0

0

0

0

14,847

othar

924

CAN Primary Industry

0

0

0

0

40,409

othar

925

CAN Manufacturing and Assembly

0

0

0

0

70,468

othar

926

CAN Distribution and Retail (no petroleum)

0

0

0

0

7,475

othar

927

CAN Commercial Services

0

0

0

0

32,096

othar

932

CAN CANRAIL

52

91,908

1,822

48

3,901

138


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Sector

Code

Mexican / Canadian Surrogate Description

nh3

NOx

pm25

so2

voc

othar

946

CAN Construction and Mining

0

0

0

0

10,211

othar

951

CAN Wood Consumption Percentage

1,010

11,223

113,852

1,603

161,174

othar

990

CAN TOTFERT

49

4,185

276

6,834

160

othar

996

CAN urbanarea

0

0

3,182

0

0

othar

1251

CAN OFFRTOTFERT

77

57,573

3,951

52

5,312

othar

1252

CAN OFFR MINES

1

849

60

1

122

othar

1253

CAN OFFR Other Construction not Urban

70

33,981

4,176

44

11,227

othar

1254

CAN OFFR Commercial Services

43

15,106

2,335

33

36,291

othar

1255

CAN OFFR Oil Sands Mines

23

12,478

410

12

1,330

othar

1256

CAN OFFR Wood industries CANVEC

8

2,680

260

5

1,018

othar

1257

CAN OFFR Unpaved Roads Rural

26

11,193

656

20

28,180

othar

1258

CAN OFFRUtilities

9

4,169

200

6

873

othar

1259

CAN OFFR total dwelling

17

6,127

619

13

12,817

othar

1260

CAN OFFRwater

23

6,736

373

31

27,471

othar

1261

CAN OFFR ALL INDUST

4

5,287

157

2

1,081

othar

1262

CAN OFFR Oil and Gas Extraction

1

1,267

78

1

229

othar

1263

CAN OFFRALLROADS

3

1,548

150

2

474

othar

1265

CAN OFFRCANRAIL

0

541

17

0

42

onroad_can

200

CAN Urban Primary Road Miles

1,617

69,363

2,232

324

7,452

onroad_can

210

CAN Rural Primary Road Miles

667

41,473

1,255

137

3,276

onroad_can

220

CAN Urban Secondary Road Miles

3,036

110,302

4,484

681

19,873

onroad_can

230

CAN Rural Secondary Road Miles

1,764

78,435

2,467

369

9,127

onroad_can

240

CAN Total Road Miles

349

48,945

1,384

76

99,474

onroad_mex

11

MEX 2015 Population

0

299,194

1,737

567

298,729

onroad_mex

22

MEX Total Road Miles

10,795

1,204,621

59,899

27,420

245,504

onroad_mex

36

MEX Commercial plus Industrial Land

0

8,520

153

31

9,594

139


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4 Analytic Year Emissions Inventories and Approaches

The emission inventories for the analytic year of 2032 have been developed using projection methods that
are specific to the type of emissions source. Analytic year emissions are projected from the base year
either by running models to estimate analytic year emissions from specific types of emission sources (e.g.,
EGUs, and onroad and nonroad mobile sources), or for other types of sources by adjusting the base year
emissions according to the best estimate of changes expected to occur in the intervening years (e.g., non-
EGU point and nonpoint sources). For some sectors, the same emissions are used in the base and analytic
years, such as biogenic, all fire sectors, and fertilizer. Emissions for these sectors are held constant in
future years because the base year meteorological data are also used for the future year air quality model
runs, and emissions for these sectors are highly correlated with meteorological conditions. For the
remaining sectors, rules and specific legal obligations that go into effect in the intervening years, along
with changes in activity for the sector, are considered when possible. For sectors that were projected, the
methods used to project those sectors to 2032 are summarized in Table 4-1.

Table 4-1. Overview of projection methods for the analytic year cases

Platform Sector:

abbreviation

Description of Projection Methods for Analytic Year Inventories

EGU units:

ptegu

The Integrated Planning Model (IPM) outputs from the EPA's Post-IRA 2022
Reference Case were used. For 2032. the 2030 IPM output vear was used.
Emission inventory Flat Files for input to SMOKE were generated using post-
processed IPM output data. A list of included rules is provided in Section 4.1.

Point source oil and
gas:

ptoilgas

First, known closures were applied to the 2018 pt_oilgas sources. Production-
related sources were then grown from 2018 to 2032 using historic production data.
The production-related sources were then grown to 2032 based on growth factors
derived from the Annual Energy Outlook (AEO) 2022 data for oil, natural gas, or a
combination thereof. The grown emissions were then controlled to account for the
impacts of New Source Performance Standards (NSPS) for oil and gas sources,
process heaters, natural gas turbines, reciprocating internal combustion engines
(RICE), and the Good Neighbor Plan for the 2015 Ozone NAAOS. These
projection factors were applied to 2018 emissions in the entire US, including the
WMP region.

Airports:

airports

Point source airport emissions were grown from 2016 to 2032 using factors
derived from the 2021 Terminal Area Forecast (TAF) released in lune 2022 (see
https://www.faa.gov/data rescarch/aviation/taf/). The 2016 emissions included
corrections to emissions for ATL from the state of Georgia, as well as some
corrections for specific airports in the state of Texas that were part of the 2016v3
platform.

Remaining non-
EGU point:

ptnonipm

2026gf from the 2016v3 platform was used as a starting point to project emissions
to 2032 using factors derived from AEO2022 to reflect growth from 2026 to 2032
(including railyards). 2026gf included controls to account for relevant NSPS for
RICE, gas turbines, refineries (subpart la), and process heaters. The Boiler MACT
is assumed to be fully implemented in 2018. Controls are reflected for the regional
haze program in Arizona and Good neighbor plan for the 2015 Ozone NAAQS. In
2026gf known closures as of that time those inventories were developed are
reflected and new sources were added based on 2019 NEI. Growth in MARAMA
states was derived from MARAMA spreadsheets after incorporating AEO 2022
data. Railyards in California were updated with CARB data for 2032. Point source
solvents are based on 2019 NEI and projected to 2032.

140


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Platform Sector:

abbreviation

Description of Projection Methods for Analytic Year Inventories

Category 1, 2 CMV:

cmv_clc2

Category 1 and category 2 (C1C2) CMV emissions sources outside of California
were projected to 2030 (2030 emissions were used to represent 2032) based on
factors from the Regulatory Impact Analysis (RIA) Control of Emissions of Air
Pollution from Locomotive Engines and Marine Compression Ignition Engines
Less than 30 Liters per Cylinder. California emissions were calculated using new
2018->2030 factors based on interpolations of the same CARB data used to
calculate factors in 2016 platforms (2030 was used for 2032). Projection factors
for Canada emissions were calculated using 2018->2028 factors based on
interpolations of the ECCC data provided for the 2016 platforms, then multiplied
by the 2028-2030 US-based factors (same as in 2032fj in the 2016v2 platform).

Category 3 CMV:

cmv_c3

Category 3 (C3) CMV emissions were projected to 2030 using an EPA report on
projected bunker fuel demand that projects fuel consumption by region out to the
year 2030 (2030 was used for 2032). Bunker fuel usage was used as a surrogate for
marine vessel activity. Factors based on the report were used for all pollutants
except NOx. The NOx growth rates from the EPA C3 Regulatory Impact
Assessment (RIA) were refactored to use the new bunker fuel usage growth rates.
Assumptions of changes in fleet composition and emissions rates from the C3 RIA
were preserved and applied to bunker fuel demand growth rates for 2030 to arrive
at the final growth rates. Projection factors for Canada emissions were calculated
using 2018->2028 factors based on interpolations of the ECCC data provided for
the 2016 platforms, then multiplied by the 2028-2030 US-based factors (same as in
2032fj in the 2016v2 platform).

Locomotives:
rail

Rail was projected from 2026fj to 2032 using AEO2022-based growth factors, plus
ERTAC-based pollutant-specific factors for Class I. California rail used new
CARB 2032 inventory.

Area fugitive dust:

afdust

Paved road dust was grown to 2032 levels based on the growth in VMT from 2018
to 2032. Emissions for the remainder of the sector including building construction,
road construction, agricultural dust, and unpaved road dust were held constant at
2018 levels.

Livestock: livestock

Livestock were projected using factors developed for 2016v3 platform. Emissions
were projected from 2018 to 2032 based on factors created from USDA National
livestock inventory projections published in 2022
(https://www.ers.usda.gov/publications/pub-details/?pubid=103309).

Nonpoint source oil
and gas:
npoilgas

Exploration-related sources were based on an average of 2017 through 2019
exploration data with NSPS controls applied, where applicable. Production-related
emissions were initially projected to 2021 using historical data and then grown to
2032 based on factors generated from AEO2022 reference case. Based on the
SCC, factors related to oil, gas, or combined growth were used. Coalbed methane
SCCs were projected independently. These projection factors were applied to 2018
production emissions in the entire US, including the WRAP region. Controls were
then applied to account for NSPS for oil and gas and RICE.

Residential Wood
Combustion:

rwc

2018 RWC emissions are the same as 2017 NEI. RWC emissions were projected
from 2018 to 2032 based on growth and control assumptions compatible with
EPA's 201 lv6.3 platform, which accounts for growth, retirements, and NSPS,
although implemented in the Mid-Atlantic Regional Air Management Association
(MARAMA)'s growth tool. Factors provided by North Carolina were used for that
state. RWC emissions in California, Oregon, and Washington were held constant
at 2017 levels.

141


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Platform Sector:

abbreviation

Description of Projection Methods for Analytic Year Inventories

Solvents:

solvents

The same projection and control factors to 2032 were applied to solvent emissions
as if these SCCs were in nonpt. Additional SCCs in the new inventory that
correlate with human population were also projected. Applied the same OTC Rules
controls as 2016v3, but only included controls that took effect after 1/1/2018.

Remaining
nonpoint:

nonpt

Projected base year to 2032 using 2016v3-consistent projection and control
packets. For the purposes of the projection packets, 2016 was used as the base
year, because the base year nonpt inventory was from only one year later
(2017NEI) and so that projection packets from 2016 platform could be reused.
Industrial emissions were grown according to factors derived from AEO2022 to
reflect growth from 2021 onward. Data from earlier AEOs were used to derive
factors through 2021. Portions of the nonpt sector were grown using factors based
on expected growth in human population. The MARAMA projection tool was used
to project emissions to 2032 after the AEO-based factors were updated to
AEO2022. Projection factors provided by North Carolina and New Jersey were
used through 2026, with MAR\MA-based projections used from 2026 to 2032.
Controls were applied to reflect relevant NSPS rules (i.e., reciprocating internal
combustion engines (RICE), natural gas turbines, and process heaters). Emissions
were also reduced in 2016v2 and v3 to account for fuel sulfur rules in the mid-
Atlantic and northeast not fully implemented by 2017. OTC controls for PFCs are
included.

Nonroad:

nonroad

Outside California and Texas and Texas, the MOVES3.0.3 model was newly run
for this case to create nonroad emissions for 2032. Fuels used in MOVES3 are
specific to 2032. Updated data from CARB were used for 2032. Texas nonroad
emissions were provided by TCEQ for 2023 and 2028, and interpolated to 2026;
they were then projected to 2032 using factors derived from MOVES.

Onroad:

onroad,

onroadnonconus

Activity data for 2018 were projected from the 2017 NEI. Activity data were then
projected to 2032 using factors derived from AEO2022. To create the emission
factors, MOVES3 was run for the year 2032 using 2018 meteorological data and
fuels, but with age distributions projected to represent 2032 and the remaining
inputs consistent with those used in 2017NEI. The 2032-specific activity data and
emission factors were then combined using SMOKE-MOVES to produce the 2032
emissions. Inspection and maintenance updates were included for NC and TN (this
changed the representative county groupings for 2032). Adjustments were applied
to reflect the Control of Air Pollution from New Motor Vehicles: Heavy-Duty
Engine and Vehicle Standards (2022) and the Final Rule to Revise Existing
National GHG Emissions Standards for Passenger Cars and Light Trucks Through
Model Year 2026 (2021). Section 4.3.2 describes the applicable rules that were
considered when projecting onroad emissions.

Onroad California:

onroad ca adj

CARB-provided emissions were used for 2032 in California.

Other Area Fugitive
dust sources not
from the NEI:
othafdust

Area fugitive dust emissions were provided by ECCC prior to 2016vl. Projection
factors were derived from those inventories and applied to the 2016v2 inventory to
estimate the 2028 emissions and those emissions were used to represent 2032 in
this platform. Mexico emissions are not included in this sector.

Other Point Fugitive
dust sources not
from the NEI:
othptdust

Base year inventories from ECCC were held flat from 2018 for the analytic year
2032, including the same transport fraction as the base year and the meteorology-
based (precipitation and snow/ice cover) zero-out.

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Platform Sector:

abbreviation

Description of Projection Methods for Analytic Year Inventories

Other point sources
not from the NEI:
othpt

Canada emissions for analytic years were provided by ECCC for use in 2016vl.
Projection factors were derived from those inventories to estimate 2028 emissions,
and those emissions were used to represent 2032. Canada projections were applied
by province-subclass where possible (i.e., where subclasses did not change
between platforms). For inventories where that was not possible, including airports
and most stationary point sources except for oil and gas, projections were applied
by province. For Mexico sources, Mexico's 2016 inventory was grown to 2028
(that inventory was used to represent 2032) using state and pollutant-specific
factors based on the 2016vl platform inventories.

Canada ag not from
the NEI:

Canada ag

Base year low-level agricultural sources were projected to 2028 (which was used
to represent 2032) using projection factors based on data provided by ECCC and
applied by province, pollutant, and ECCC sub-class code.

Canada oil and gas
2D not from the
NEI:

Canada og2D

Low-level point oil and gas sources from the ECCC 2016 emission inventory were
projected to the analytic years based on province-subclass changes in the ECCC-
provided data used for 2016vl. 2028 projections were used to represent 2032.

Other non-NEI
nonpoint and
nonroad:

othar

Analytic year Canada nonpoint inventories were provided by ECCC for 2016vl.
For Canadian nonpoint sources, factors were provided from which the analytic
year inventories could be derived. Projection factors for 2028 were derived from
those inventories and applied to the 2016v2 Canada nonpoint inventory to
represent 2032. For Canada nonroad, the previously generated 2026 data from
2016v2 platform was projected to 2032 using trends calculated from MOVES in
the US. For Mexico nonpoint and nonroad sources, state-pollutant projection
factors for 2028 were calculated from the 2016vl inventories, and then applied to
the 2016v2 base year inventories, with 2028 representing 2032.

Other non-NEI
onroad sources:

onroadcan

For Canadian mobile onroad sources, analytic year inventories were projected
from 2016 to 2026 using ECCC-provided projection data from vl platform at the
province and subclass (which is similar to SCC but not exactly) level. The
previously generated 2026 data from 2016v2 platform was projected to 2032 using
trends calculated from MOVES in the US.

Other non-NEI
onroad sources:

onroad mex

Monthly onroad mobile inventories were developed at municipio resolution based
on an interpolation of runs of MOVES-Mexico for 2028 and 2035.

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4.1 EGU Point Source Projections (ptegu)

The 2032 EGU emissions inventories relied on the EPA's Post-IRA 2022 Reference Case of the
Integrated Planning Model (IPM), with additional update of Final Good Neighbor Plan (GNP). IPM is a
linear programming model that accounts for variables and information such as energy demand, planned
unit retirements, and planned rules to forecast unit-level energy production and configurations. The
following specific rules and regulations are included in the IPM run (see the Final PM NAAQS web page
for more details, documentation of inputs and outputs to the modeling projections for this analysis):

•	Final Good Neighbor Plan for 2015 Ozone NAAQS.

Inflation Reduction Act of 2021 (reflecting Tax Credits).

The Revised Cross-State Air Pollution Rule (CSAPR) Update, a federal regulatory measure
affecting EGU emissions from 12 states to address transport under the 2008 National Ambient Air
Quality Standards (NAAQS) for ozone.

The Standards of Performance for Greenhouse Gas Emissions from New, Modified, and
Reconstructed Stationary Sources: Electric Utility Generating Units through rate limits.

•	The Mercury and Air Toxics Rule (MATS) finalized in 2011. MATS establishes National
Emissions Standards for Hazardous Air Pollutants (NESHAP) for the "electric utility steam
generating unit" source category.

Current and existing state regulations, including current and existing Renewable Portfolio
Standards and Clean Energy Standards as of the summer of 2021.

The latest actions EPA has taken to implement the Regional Haze Regulations and Guidelines for
Best Available Retrofit Technology (BART) Determinations Final Rule. The BART limits
approved in these plans (as of summer 2020) that will be in place for EGUs are represented in the
Updated Summer 2021 Reference Case.

California AB 32 C02 allowance price projections and the Regional Greenhouse Gas Initiative
(RGGI) rule.

Three non-air federal rules affecting EGUs: National Pollutant Discharge Elimination System-
Final Regulations to Establish Requirements for Cooling Water Intake Structures at Existing
Facilities and Amend Requirements at Phase I Facilities, Hazardous, and Solid Waste
Management System; Disposal of Coal Combustion Residuals from Electric Utilities; and the
Effluent Limitation Guidelines and Standards for the Steam Electric Power Generating Point
Source Category.

IPM is run for a set of years, including 2030 and 2035. 2030 outputs were used in this analysis. All inputs,
outputs and full documentation of EPA's Post-IRA 2022 Reference Case and the associated EGU fleet
information (NEEDS for EPA Post-IRA 2022 Reference Case rev:	are available on the Final

PM NAAQS modeling. Some of the key parameters used in the IPM run are:

•	Demand: AEO 2021 + on-the-books OTAQ GHG Rules

•	Gas and Coal Market assumptions: updated as of December 2021

•	Cost and performance of fossil generation technologies: AEO 2021

•	Cost and performance of renewable energy generation technologies: NREL ATB 2021 (mid-case)

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•	Environmental rules and regulations (on-the-books): Final GNP, Revised CSAPR, MATS, BART,
CA AB 32, RGGI, various RPS and CES, non-air rules (Cooling Water Intake, ELC, CCR), State
Rules and mandates

•	Financial assumptions: 2016-2020 data, reflects tax credit extensions from Consolidated
Appropriations Act of 2021

•	Transmission: updated data with build options

•	Retrofits: carbon capture and sequestration option for CCs

•	Operating reserves (in select runs): Greater detail in representing interaction of load, wind, and
solar, ensuring availability of quick response of resources at higher levels of RE penetration

•	Fleet: NEEDS i	>st-IRA 2022 Reference Case rev: 10-14-22

The 2030 outputs of the IPM projections were used for the 2032 inventory. Units that are identified to
have a primary fuel of landfill gas, fossil waste, non-fossil waste, residual fuel oil, or distillate fuel oil
may be missing emissions values for certain pollutants in the generated inventory flat file. Units with
missing emissions values are gapfilled using projected base year values. The projections are calculated
using the ratio of the analytic year seasonal generation in the IPM parsed file and the base year seasonal
generation at each unit for each fuel type in the unit as derived from EIA-923 tables and the 2018 NEI.
New controls identified at a unit in the IPM parsed file are accounted for with appropriate emissions
reductions in the gapfill projection values. When base year unit-level generation data cannot be obtained
no gapfill value is calculated for that unit.

Once IPM has been run, a process is performed to first parse the results to unit level and then to generate a
flat file in a format that SMOKE can read. To accomplish this, a cross reference file is needed to map the
NEEDS IDs to NEI IDs for facility and unit and for stack parameters. The cross reference file used for the
IPM outputs was "NEEDS NEIjcrej' 2016 2019stk 13apr22.xlsxn and incorporates information about
unit and stack configurations from the 2019 NEI Point source inventory. The flat file that results from this
process includes emissions for five summer months (May to September), four "shoulder" months (March,
April, October, November) and three winter months (January, February, and December). The emissions
from each of these "seasons" were placed into separate flat files so that SMOKE can preserve the total
emissions within each season to the extent possible within rounding errors. Large EGUs in the IPM-
derived flat file inventory are associated with hourly CEMS data for NOX and S02 emissions values in
the base year. To maintain a temporal pattern consistent with the base year, the NOX and S02 values in
the base year hourly CEMS inventories are projected to match the total seasonal emissions values in the
analytic years as described in Section 3.3.2.2.

Combined cycle units produce some of their energy from process steam that turns a steam turbine. The
IPM model assigns a fraction of the total combined cycle production to the steam turbine. When the
emissions are calculated these steam units are assigned emissions values that come from the combustion
portion of the process. In the base year NEI steam turbines are usually implicit to the total combined cycle
unit. To achieve the proper plume rise for the total combined cycle emissions, the stack parameters for the
steam turbine units were updated with the parameters from the combustion release point. Additionally,
some units, such as landfill gas, may not be assigned a valid SCC in the initial flat file. The SCCs for
these units were updated based on the base year SCC for the unit-fuel type.

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The EGU sector N0X emissions by state are listed in Table 4-2 for the cases that comprise this platform.
The state total emissions in this table may not exactly match the sum of the emissions for each state in the
flat files for each season due to the process of apportioning seasonal total emissions to hours for input to
SMOKE followed by summing the daily emissions back up to annual. However, any difference should be
well within one percent of the state total emissions.

Table 4-2. EGU sector NOx emissions by State for the 2018v2 cases

State

2018gg

2032gg2

Alabama

27,026

10,596

Arizona

20,658

5,700

Arkansas

23,203

3,344

California

7,326

6,988

Colorado

20,016

2,146

Connecticut

3,818

2,415

Delaware

1,093

634

District of Columbia

NA

11

Florida

52,308

23,390

Georgia

29,172

7,530

Idaho

1,238

767

Illinois

34,258

7,023

Indiana

65,695

21,206

Iowa

25,880

20,056

Kansas

14,164

929

Kentucky

47,728

10,302

Louisiana

37,962

9,037

Maine

4,824

3,094

Maryland

8,691

2,478

Massachusetts

6,608

5,575

Michigan

47,391

16,734

Minnesota

21,469

3,090

Mississippi

16,380

4,672

Missouri

51,292

24,481

Montana

14,940

8,860

Nebraska

22,751

17,669

Nevada

4,788

2,558

New Hampshire

2,371

545

New Jersey

6,706

4,344

New Mexico

11,378

1,131

New York

15,512

10,653

North Carolina

36,939

5,064

North Dakota

34,009

19,602

Ohio

50,958

15,096

Oklahoma

22,084

2,689

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State

2018gg

2032gg2

Oregon

4,198

518

Pennsylvania

38,097

18,268

Rhode Island

577

567

South Carolina

15,132

4,628

South Dakota

1,193

1,205

Tennessee

9,132

1,489

Texas

110,843

22,197

Tribal Areas

23,755

2,762

Utah

25,601

6,111

Vermont

231

27

Virginia

23,233

8,070

Washington

10,096

2,398

West Virginia

41,410

16,532

Wisconsin

15,667

4,565

Wyoming

33,380

13,428

4.2 Sectors with Projections Computed using CoST

To project U.S. emissions for sectors other than EGUs, facility/unit closures information, growth
(projection) factors and/or controls were applied to certain categories within those sectors. Some facility
or sub-facility-level closure information was applied to the point sources. There are also a handful of
situations where new inventories were generated for sources that did not exist in the NEI (e.g., biodiesel
and cellulosic plants, yet-to-be constructed cement kilns). This subsection provides details on the data and
projection methods used to develop analytic year emissions for sectors other than EGUs that were
developed using the Control Strategy Tool.

Because the projection and control data are developed mostly independently from how the emissions
modeling sectors are defined, this section is organized primarily by the type of projections data, with
secondary consideration given to the emissions modeling sector (e.g., industrial source growth factors are
applicable to multiple emissions modeling sectors). The rest of this section is organized in the order that
the EPA uses the Control Strategy Tool (CoST) in combination with other methods to produce analytic
year inventories: 1) for point sources, apply facility or sub-facility-level closure information via CoST; 2)
apply all PROJECTION packets via CoST (these contain multiplicative factors that could cause increases
or decreases); 3) apply all percent reduction-based CONTROL packets via CoST; and 4) append any
other analytic-year inventories not generated via CoST. This organization allows consolidation of the
discussion of the emissions categories that are contained in multiple sectors, because the data and
approaches used across the sectors are consistent and do not need to be repeated. Sector names associated
with the CoST packets are provided in parentheses following the subsection titles.

The impacts of the projection and control factors on the emissions for each sector are shown in tables in
this section. In addition, the actual projection and control factors used to develop the analytic year
emissions are shown when they are general enough to fit into a table of reasonable length, although in
some cases, there are hundreds or thousands of factors used and the tables would be too large. To see

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these factors, visit the spreadsheets: 2032gg2 CoST_projection_packets llmay2023.xlsx and
2032gg2 CoST_projection_packets 1 lmay2023.xlsx on the FTP site for this platform.

4.2.1 Background on the Control Strategy Tool (CoST)

CoST is used to apply most non-EGU projection/growth factors, controls and facility/unit/stack-level
closures to the base year emissions modeling inventories to create analytic year inventories for the
following sectors: afdust, airports, cmv, livestock, nonpt, np oilgas, np solvents, pt oilgas, ptnonipm,
rail, and rwc. Information about CoST and related data sets is available from

https://www.epa.gov/economic-and-cost-analvsis-air-pollution-regulations/cost-analvsis-modelstools-air-
pollution.

CoST allows the user to apply projection (growth) factors, controls and closures at various geographic
and inventory key field resolutions. Using these CoST datasets, also called "packets" or "programs,"
supports the process of developing and quality assuring control assessments as well as creating SMOKE-
ready analytic year (i.e., projected) inventories. Analytic year inventories are created for each emissions
modeling sector by applying a CoST control strategy type called "Project future year inventory" and each
strategy includes all base year inventories and applicable CoST packets. For reasons to be discussed later,
some emissions modeling sectors may require multiple CoST strategies to account for the compounding
of control programs that impact the same type of sources. There are also available linkages to existing and
user-defined control measure databases and it is up to the user to determine how control strategies are
developed and applied. The EPA typically creates individual CoST packets that represent specific
intended purposes (e.g., aircraft projections for airports are in a separate PROJECTION packet from
residential wood combustion sales/appliance turnover-based projections). CoST uses three packet types:

•	CLOSURE: Closure packets are applied first in CoST. This packet can be used to zero-out (close)
point source emissions at resolutions as broad as a facility to as specific as a release point. The
EPA uses these types of packets for known post-base year controls as well as information on
closures provided by states on specific facilities, units or release points. This packet type is only
used for the ptnonipm and pt oilgas sectors.

•	PROJECTION: Projection packets support the increase or decrease in emissions for virtually any
geographic and/or inventory source level. Projection factors are applied as multiplicative factors to
the base year emissions inventories prior to the application of any possible subsequent
CONTROLS. A PROJECTION packet is necessary whenever emissions increase from the base
year and is also desirable when information is based more on activity assumptions rather than on
known control measures. The EPA uses PROJECTION packet(s) for many modeling sectors.

•	CONTROL: Control packets are applied after any/all CLOSURE and PROJECTION packet
entries. They support of similar level of specificity of geographic and/or inventory source level
application as PROJECTION packets. Control factors are expressed as a percent reduction (0 -
meaning no reduction, to 100 - meaning full reduction) and can be applied in addition to any pre-
existing inventory control, or as a replacement control. For replacement controls, any controls
specified in the inventory are first backed out prior to the application of a more-stringent
replacement control).

These packets use comma-delimited formats and are stored as data sets within the Emissions Modeling
Framework. As mentioned above, CoST first applies any/all CLOSURE information for point sources,

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then applies PROJECTION packet information, followed by CONTROL packets. A hierarchy is used by
CoST to separately apply PROJECTION and CONTROL packets. In short, in a separate process for
PROJECTION and CONTROL packets, more specific information is applied in lieu of less-specific
information in ANY other packets. For example, a facility-level PROJECTION factor will be replaced by
a unit-level, or facility and pollutant-level PROJECTION factor. It is important to note that this hierarchy
does not apply between packet types (e.g., CONTROL packet entries are applied irrespective of
PROJECTION packet hierarchies). A more specific example: a state/SCC-level PROJECTION factor will
be applied before a stack/pollutant-level CONTROL factor that impacts the same inventory record.
However, an inventory source that is subject to a CLOSURE packet record is removed from consideration
of subsequent PROJECTION and CONTROL packets.

The implication for this hierarchy and intra-packet independence is important to understand and quality
assure when creating future year strategies. For example, with consent decrees, settlements and state
comments, the goal is typically to achieve a targeted reduction (from the base year inventory) or a
targeted analytic-year emissions value. Therefore, controls due to consent decrees and state comments for
specific cement kilns (expressed as CONTROL packet entries) need to be applied instead of (not in
addition to) the more general approach of the PROJECTION packet entries for cement manufacturing. By
processing CoST control strategies with PROJECTION and CONTROL packets separated by the type of
broad measure/program, it is possible to show actual changes from the base year inventory to the future
(i.e., analytic) year inventory as a result of applying each packet.

Ultimately, CoST concatenates all PROJECTION packets into one PROJECTION dataset and uses a
hierarchal matching approach to assign PROJECTION factors to the inventory. For example, a packet
entry with Ranking=l will supersede all other potential inventory matches from other packets. CoST then
computes the projected emissions from all PROJECTION packet matches and then performs a similar
routine for all CONTROL packets. Therefore, when summarizing "emissions reduced" from CONTROL
packets, it is important to note that these reductions are not relative to the base year inventory, but rather
to the intermediate inventory after application of any/all PROJECTION packet matches (and
CLOSURES). A subset of the more than 70 hierarchy options is shown in Table 4-3, where the fields in
the table are similar to those used in the SMOKE FF10 inventories. For example, "REGIONCD" is the
county-state-county FIPS code (e.g., Harris county Texas is 48201) and "STATE" would be the 2-digit
state FIPS code with three trailing zeroes (e.g., Texas is 48000).

Table 4-3. Subset of CoST Packet Matching Hierarchy

Rank

Matching Hierarchy

Inventory Type

1

REGION CD, FACILITY ID, UNIT ID, REL POINT ID, PROCESS ID, SCC, POLL

point

2

REGION CD, FACILITY ID, UNIT ID, REL POINT ID, PROCESS ID, POLL

point

3

REGION CD, FACILITY ID, UNIT ID, REL POINT ID, POLL

point

4

REGION CD, FACILITY ID, UNIT ID, POLL

point

5

REGION CD, FACILITY ID, SCC, POLL

point

6

REGION CD, FACILITY ID, POLL

point

7

REGION CD, FACILITY ID, UNIT ID, REL POINT ID, PROCESS ID, SCC

point

8

REGION CD, FACILITY ID, UNIT ID, REL POINT ID, PROCESS ID

point

9

REGION CD, FACILITY ID, UNIT ID, REL POINT ID

point

10

REGION CD, FACILITY ID, UNIT ID

point

11

REGION CD, FACILITY ID, SCC

point

12

REGION CD, FACILITY ID

point

13

REGION CD, NAICS, SCC, POLL

point, nonpoint

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Rank

Matching Hierarchy

Inventory Type

14

REGION CD, NAICS, POLL

point, nonpoint

15

STATE, NAICS, SCC, POLL

point, nonpoint

16

STATE, NAICS, POLL

point, nonpoint

17

NAICS, SCC, POLL

point, nonpoint

18

NAICS, POLL

point, nonpoint

19

REGION CD, NAICS, SCC

point, nonpoint

20

REGION CD, NAICS

point, nonpoint

21

STATE, NAICS, SCC

point, nonpoint

22

STATE, NAICS

point, nonpoint

23

NAICS, SCC

point, nonpoint

24

NAICS

point, nonpoint

25

REGION CD, SCC, POLL

point, nonpoint

26

STATE, SCC, POLL

point, nonpoint

27

SCC, POLL

point, nonpoint

28

REGION CD, SCC

point, nonpoint

29

STATE, SCC

point, nonpoint

30

SCC

point, nonpoint

31

REGION CD, POLL

point, nonpoint

32

REGION CD

point, nonpoint

33

STATE, POLL

point, nonpoint

34

STATE

point, nonpoint

35

POLL

point, nonpoint

The contents of the controls, local adjustments and closures for the analytic year cases are described in the
following subsections. Year-specific projection factors (PROJECTION packets) for each analytic year
were used to create the analytic year cases, unless noted otherwise in the specific subsections. The
contents of a few of these projection packets (and control reductions) are provided in the following
subsections where feasible. However, most sectors used growth or control factors that varied
geographically, and their contents could not be provided in the following sections (e.g., facilities and units
subject to the Boiler MACT reconsideration has thousands of records). The remainder of Section 4.2 is
divided into subsections that are summarized in Table 4-4. Note that independent analytic year inventories
were used rather than projection or control packets for some sources.

Table 4-4. Summary of non-EGU stationary projections subsections

Subsection

Title

Sector(s)

Brief Description

4.2.2

CoST Plant CLOSURE
packet

ptnonipm,
ptoilgas

All facility/unit/stack closures information,
primarily from Emissions Inventory System (EIS),
but also includes information from states and other
organizations.

4.2.3

CoST PROJECTION
packets

All

Introduces and summarizes national impacts of all
CoST PROJECTION packets to the analytic year.

4.2.3.1

Fugitive dust growth

Afdust

PROJECTION packet: county-level resolution,
primarily based on VMT growth.

4.2.3.2

Livestock population
growth

Livestock

PROJECTION packet: national, by-animal type
resolution, based on animal population projections.

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Subsection

Title

Sector(s)

Brief Description

4.2.3.3

Category 1 and 2
commercial marine
vessels

cmv clc2

PROJECTION packet: Category 1 & 2: CMV uses
SCC/poll for all states except Calif.

4.2.3.4

Category 3 commercial
marine vessels

cmv c3

PROJECTION packet: Category 3: region-level by-
pollutant, based on cumulative growth and control
impacts from rulemaking.

4.2.3.5

Oil and gas and
industrial source
growth

nonpt,
npoilgas,
ptnonipm,
ptoilgas

Several PROJECTION packets: varying geographic
resolutions from state, county, and by-process/fuel-
type applications. Data derived from AEO2022
were used for nonpt, ptnonipm, np oilgas, and
pt oilgas sectors.

4.2.3.6

Non-IPM Point
Sources

Ptnonipm

Several PROJECTION packets: specific projections
from MARAMA region and states, AEO-based
projection factors for industrial sources for non-
MARAMA states.

4.2.3.7

Airport Sources

Ptnonipm

PROJECTION packet: by-airport for all direct
matches to FAA Terminal Area Forecast data, with
state-level factors for non-matching NEI airports.

4.2.3.8

Nonpoint sources

nonpt

Several PROJECTION packets: MARAMA states
projection for Portable Fuel Containers and for all
other nonpt sources. Non-MARAMA states
projected with AEO-based factors for industrial
sources. Evaporative Emissions from Finished
Fuels projected using AEO-based factors. Human
population used as growth for applicable sources.

4.2.3.9

Solvents

npsolvents

Several PROJECTION packets including
population-based, and MARAMA state factors.

4.2.3.10

Residential wood
combustion

rwc

PROJECTION packet: national with exceptions,
based on appliance type sales growth estimates and
retirement assumptions and impacts of recent
NSPS.

4.2.4

CoST CONTROL

ptnonipm,

Introduces and summarizes national impacts of all



packets

nonpt,
npoilgas,
pt_oilgas,
np solvents

CoST CONTROL packets to the analytic year.

4.2.4.1

Oil and Gas NSPS

npoilgas,
pt oilgas

CONTROL packets: reflect the impacts of the
NSPS for oil and gas sources.

4.2.4.2

RICE NSPS

ptnonipm,
nonpt,
npoilgas,
pt oilgas

CONTROL packets apply reductions for lean burn,
rich burn, and combined engines for identified
SCCs.

4.2.4.3

Fuel Sulfur Rules

ptnonipm,
nonpt

CONTROL packet: updated by MARAMA, applies
reductions to specific units in ten states.

4.2.4.4

Natural Gas Turbines
NOx NSPS

ptnonipm

CONTROL packets apply NOx emission reductions
established by the NSPS for turbines.

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Subsection

Title

Sector(s)

Brief Description

4.2.4.5

Process Heaters NOx
NSPS

ptnonipm

CONTROL packet: applies NOx emission limits
established by the NSPS for process heaters.

4.2.4.6

Ozone Transport
Commission Rules

nonpt,
np solvents

CONTROL packets reflecting rules for solvents and
portable fuel containers.

4.2.2 CoST CLOSURE Packet (ptnonipm, pt_oilgas)

Packets:

CLOSURES2016v3_platform_ptnonipm_09j an2023_v 1

The CLOSURES packet contains facility, unit and stack-level closure information derived from an
Emissions Inventory System (EIS) unit-level report from June 9, 2021, with closure status equal to "PS"
(permanent shutdown; i.e., post-2018 permanent facility/unit shutdowns known in EIS as of the date of
the report). The starting point for the closures packet was the version from the 2016v3 platform. For
2018v2, additional closures were added and those are cumulative with the closures in 2018gc. Any data
provided by commenters for closures were updated to match the SMOKE FF10 inventory key fields, with
all duplicates removed, and a single CoST packet was generated. These changes impact sources in the
ptnonipm and ptoilgas sectors. Additional closures provided in comments on the 2018gc inventories
were incorporated in the 2018v2 platform for multiple states including Ohio, Wisconsin, North Carolina,
and North Dakota. The spreadsheet in the reports folder on the 2016v3 FTP site called
point controlsjpacket 2016v3.xlsx lists all closures, while the spreadsheet called
ptnonipm 19 2023gf new closures.xlsx available lists the closures there were new in 2016v3 and their
impacts. The cumulative reduction in emissions for ptnonipm and pt oilgas are shown in Table 4-5. The
amount of emission reductions are from 2019 emissions levels, not 2016 emissions, because the closures
were applied to the 2019 inventory that was used as the starting point for the projection to 2032.

Table 4-5. Reductions from all facility/unit/stack-level closures in 2032 from 2018 emissions levels

Pollutant

ptoilgas

CO

985

NH3

0

NOX

2,154

PM10

30

PM2.5

30

S02

1

VOC

193

4.2.3 CoST PROJECTION Packets (afdust, airports, cmv, livestock, nonpt,
np_oilgas, np_solvents, ptnonipm, pt_oilgas, rail, rwc)

For point inventories, after the application of any/all CLOSURE packet information, the next step CoST
performs when running a control strategy is to apply all of the PROJECTION packets. Regardless of
inventory type (point or nonpoint), the PROJECTION packets are applied prior to the CONTROL
packets. For several emissions modeling sectors (e.g., airports, np oilgas, pt oilgas), there is only one

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PROJECTION packet applied for each analytic year. For other sectors, there may be several different
sources of projection data and as a result there are multiple PROJECTION packets that are concatenated
by CoST during a control strategy run. The outputs are then quality-assured regarding duplicates and
applicability to the inventories in the CoST strategy. Similarly, CONTROL packets are kept in distinct
datasets for different control programs. Having the PROJECTION (and CONTROL) packets separated
into "key" projection and control programs allows for quick summaries of the impacts of these distinct
control programs on emissions.

Throughout the process of developing the 2016 platforms, MARAMA provided projection factors for
states including: Connecticut, Delaware, Maryland, Massachusetts, New Hampshire, New York, New
Jersey, North Carolina, Pennsylvania, Rhode Island, Vermont, Virginia, West Virginia, Maine, and the
District of Columbia. Some other states also provided projection factors. Many of these were based on
data from the AEO available at the time the factors were generated. For the 2016v2 platform, MARAMA
provided new spreadsheets of projection factors to facilitate the incorporation of newer AEO data
available at that time, along with and other surrogate data used for projection factors. The new
spreadsheets also reflected sources affected by the Pennsylvania Reasonably Available Control
Technology (RACT) II. The data in these spreadsheets were further updated for the 2016v3 platform to
use factors based on AEO 2022. For some sectors, the 2016v3 inventories for the year 2026 were used as
the starting point for projection emissions to 2032 in this study. This facilitated the retention of some
state-provided data from the 2016 platforms in this platform. For states not covered by the MARAMA or
other state-provided packets, projection factors were developed using nationally available data and
methods.

Quantitative impacts of the projections on the emissions by sector nationally and by state are available in
the reports folder on the FTP site in the file 2032gg2projections by sector_packet.xlsx. Some excerpts
from this workbook are included in the subsections that follow.

4.2.3.1 Fugitive dust growth (afdust)

Packets:

Projection_2018_2032_afdust_paved_roads_for2032gg_14sep2022_v0

For paved roads (SCC 2294000000), the 2018 afdust emissions were projected to analytic year 2032
based on differences in county total VMT:

Analytic year afdust paved roads = 2018 afdust paved roads * (Analytic year county total VMT) /

(2018 county total VMT)

The VMT projections are described in the onroad section. Paved road dust emissions were projected this
way in all states, including MARAMA states. All emissions other than paved roads are held constant in
the analytic year projections. Unlike in 2016v3 platform, separate projection packets for the MARAMA
region were not use for this study for this sector. The impacts of the projections are shown in Table 4-6.

Table 4-6. Increase in PM2.5 emissions from projections in 2018v2

Sector

2018
Emissions

2032
Emissions

Percent Increase in
2032

Paved Roads

1,580,736

1,888,454

19.47%

All afdust

2,283,902

2,357,271

3.11%

153


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4.2.3.2 Airport sources (airports)

Packets:

airport_proj ections_itn_taf2021_2016_2032_25apr2022_v0

Airport emissions for 2016v3 were projected from the 2016 airport emissions to 2032 based on TAF 2021
based on the corrected 2017 NEI airport emissions (released in June 2022), and starting from the base
year 2016 instead of 2017. Year 2016 emissions were the starting point because they included corrections
to some airports in Georgia and Texas that were not in the 2017 NEI. The Terminal Area Forecast (TAF)
data available from the Federal Aviation Administration (see
https://www.faa.gov/data research/aviation/taf/Y

Projection factors were computed using the ratio of the itinerant (ITN) data from the Airport Operations
table between the base and projection year. Where possible, airport-specific projection factors were used.
For airports that could not be matched to a unit in the TAF data, state default growth factors by itinerant
class (i.e., commercial, air taxi, and general) were created from the set of unmatched airports. Emission
growth factors for facilities from 2016 to 2032 were limited to a range of 0.2 (80% reduction) to 5.0
(400% growth), and the state default projection factors were limited to a range of 0.5 (50% reduction) to
2.0 (100%) growth). Military state default projection values were kept flat (i.e., equal to 1.0) to reflect
uncertainly in the data regarding these sources. The projection factors for 25 major airports in the
Continental US are shown in Table 4-7. Separate projection factors are applied to commercial aviation,
general aviation, and air taxi SCCs. For airports without a projection factor specific to the air taxi
category, a state average projection factor is used. The national impact of the projections on airport
emissions from 2016 to 2032 is shown in Table 4-8.

Table 4-7. TAF 2021 growth factors for major airports, 2016 to 2032

Facility ID

State

Airport

Commercial
Aviation

General
Aviation

Air Taxi

10583311

Arizona

Phoenix (PHX)

1.5718

1.0276

0.5803

2255111

California

Los Angeles (LAX)

1.4171

0.7881

0.4868

9997011

California

San Francisco (SFO)

1.5497

0.9495

0.3167

9816811

Colorado

Denver (DEN)

1.6638

1.2331

0.3694

9762111

Florida

Orlando (MCO)

1.5906

1.0984

1.0474

9791511

Florida

Fort Lauderdale (FLL)

1.6579

1.0083

1.4303

9806211

Florida

Miami (MIA)

1.3662

0.9082

0.6174

9748811

Georgia

Atlanta (ATL)

1.4741

1.0626

n/a

2681611

Illinois

Chicago O'Hare (ORD)

1.8234

0.7652

n/a

9562811

Massachusetts

Boston (BOS)

1.5039

1.3743

0.9986

9535411

Michigan

Detroit (DTW)

1.5078

1.1021

n/a

6151711

Minnesota

Minneapolis (MSP)

1.4789

0.8776

0.2454

9392311

Nevada

Las Vegas (LAS)

1.3173

1.0173

1.0626

9376211

New Jersey

Newark (EWR)

1.5739

1.1233

n/a

9333211

New York

La Guardia (LGA)

1.2305

0.8187

n/a

9333311

New York

John F Kennedy (JFK)

1.4134

1.5807

0.2286

9279611

North Carolina

Charlotte (CLT)

1.7513

1.0288

n/a

154


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Commercial

General



Facility ID

State

Airport

Aviation

Aviation

Air Taxi

9246511

Oregon

Portland (PDX)

1.4561

0.9561

0.9602

9185011

Pennsylvania

Philadelphia (PHL)

1.5738

1.0464

n/a

9171111

Tennessee

Memphis (MEM)

1.4163

0.9277

0.5331

9076711

Texas

Dallas/Fort Worth (DFW)

1.6638

0.9549

n/a

9128911

Texas

Houston Intercontinental (IAH)

1.5991

0.9606

n/a

9076611

Utah

Salt Lake City (SLC)

1.6959

1.2681

0.5587

9063811

Virginia

Washington Dulles (IAD)

1.6017

0.957

0.4119

9093911

Washington

Seattle (SEA)

1.4455

0.7548

0.5497

Table 4-8. Impact of 2016 to 2032 factors on airport emissions

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

494,548

589,941

95,393

19.3%

NOX

128,306

170,662

42,356

33.0%

PM10-PRI

10,267

11,051

785

7.6%

PM25-PRI

8,969

9,711

742

8.3%

S02

15,472

20,874

5,402

34.9%

VOC

55,234

65,524

10,290

18.6%

CO

494,548

589,941

95,393

19.3%

4.2.3.3 Category 1, Category 2 Commercial Marine Vessels (cmv_c1c2)

Packets:

Proj ecti on_2018_203 0_cmv_c 1 c2_for_2032gg_l 5 sep2022_v0
Proj ecti on_2018_203 0_cmv_Canada_for_2032gg_l 5 sep2022_v0

Category 1 and category 2 (C1C2) CMV emissions sources outside of California were projected to 2030
(with 2030 used for 2032) based on factors derived from the Regulatory Impact Analysis (RIA) Control
of Emissions of Air Pollution from Locomotive Engines and Marine Compression Ignition Engines Less
than 30 Liters per Cylinder (https://www.epa.gov/regulations-emissions-vehicles-and-engines/final-rule-
control-emissions-air-pollution-locomotive). The 2030 cmv_clc2 emissions for 2018v2 are based on the
same base year data as the 2018gc emissions. California cmv_clc2 emissions were projected based on
factors provided by the state. Table 4-9 lists the pollutant-specific projection factors to 2030 that were
used for cmv_clc2 sources outside of California. California sources were projected to 2030 using the
factors in Table 4-10, which are based on data provided by CARB.

Projection factors for Canada for 2030 were based on ECCC-provided 2023 and 2028 data projected to
2030.

155


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Table 4-9. National projection factors for cmv_clc2

Pollutant

U.S. 2018-to-2030 (%)

Canada 2028 to 2030 (%)

CO

+2.4%

+1.0%

NOX

-44.2%

-8.4%

PM10

-42.5%

-8.8%

PM2.5

-42.5%

-8.8%

S02

-46.7%

-0.6%

VOC

-46.0%

-7.8%

Table 4-10. California projection factors for cmv_clc2

Pollutant

2018-to-2030 (%)

CO

+19.6%

NOX

-15.8%

PM10

-29.8%

PM2.5

-29.8%

S02

+50.5%

VOC

+0.1%

4.2.3.4 Category 3 Commercial Marine Vessels (cmv_c3)

Packets:

Proj ecti on_2018_203 0_cmv_c3_for_2032gg_l 5 sep2022_v0
Proj ecti on_2018_203 0_cmv_Canada_for_2032gg_l 5 sep2022_v0

Growth rates for cmv_c3 emissions from 2018 to 2030 (with 2030 emissions used to represent 2032) were
projected using an EPA report on projected bunker fuel demand that included values through 2030.

Bunker fuel usage was used as a surrogate for marine vessel activity. Bunker fuel usage was used as a
surrogate for marine vessel activity. Factors based on the report were used for all pollutants except NOx.

Growth factors for NOx emissions were handled separately to account for the phase in of Tier 3 vessel
engines. To estimate these emissions, the NOx growth rates from the EPA C3 Regulatory Impact
Assessment (RIA)25 were refactored to use the new bunker fuel usage growth rates. The assumptions of
changes in fleet composition and emissions rates from the C3 RIA were preserved and applied to the new
bunker fuel demand growth rates for 2030 to arrive at the final growth rates. The Category 3 marine diesel
engines Clean Air Act and International Maritime Organization standards from April, 2010
(https://www.epa.gov/regulations-emissions-vehicles-and-engines/final-rule-control-emissions-new-
marine-compression-O) were also considered when computing the emissions.

The 2030 cmv_c3 emissions for 2018v2 are based on the same base year data as the 2018gc emissions for
this sector. Projection factors for Canada for 2030 were based on ECCC-provided 2023 and 2028 data
projected to 2030.

25 https://nepis.epa.gov/Exe/ZvPURL.cgi?Dockev=P1005ZGH.TXT.

156


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The 2030 projection factors are shown in Table 4-11. Some regions for which 2018 projection factors
were available did not have 2030 projection factors specific to that region, so factors from another region
were used as follows:

•	Alaska was proj ected using North Pacific factors.

•	Hawaii was projected using South Pacific factors.

•	Puerto Rico and Virgin Islands were projected using Gulf Coast factors.

•	Emissions outside Federal Waters (FIPS 98) were projected using the factors given in
Table 4-11 for the region "Other."

•	California was projected using a separate set of state-wide projection factors based on
CMV emissions data provided by the California Air Resources Board (CARB). These
factors are shown in Table 4-12

Table 4-11. 2018-to-2030 CMV C3 projection factors outside of California

Region

US 2018-to-

US 2018-to-2030

Canada 2028-to-

Canada 2028-to-



2030

other pollutants

2030

2030



NOX



NOX

other pollutants

US East Coast

-5.7%

+48.3%

-0.6%

+5.8%

US South Pacific









(excl. California)

-31.0%

+50.8%

n/a

n/a

US North Pacific

-2.9%

+41.0%

-0.3%

+4.6%

US Gulf

-13.1%

+35.7%

n/a

n/a

US Great Lakes

+23.0%

+29.3%

+3.7%

+4.3%

Other

+42.7%

+42.7%

n/a

n/a

Non-Federal Waters

2018-to-2030

S02

-73.6%

PM (main engines)

-25.9%

PM (aux. engines)

-30.1%

Other pollutants

+42.7%

Table 4-12. 2018-to-2030 CMV C3 projection factors for California

Pollutant

2018-to-2030

CO

+33.2%

NOx

+27.9%

PMio / PM2.5

+36.7%

S02

+32.3%

voc

+44.3%

4.2.3.5 Livestock population growth (livestock)

Packets:

Projection_2018gg_2032gg_ag_livestock_12sep2022_v0

157


-------
The 2018v2 livestock emissions were projected to year 2032 using projection factors created from USDA
National livestock inventory projections published in February 2022

(https://www.ers.usda.gov/publications/pub-details/?pubid=103309) and are shown in Table 4-13, along
with the overall impacts on the livestock NH3 and VOC emissions. For emission projections to 2032, a
ratio was created between animal inventory counts for 2032 and 2018 to create a projection factor. This
process was completed for the animal categories of beef, dairy, broilers, layers, turkeys, and swine. The
projection factor was then applied to the base year emissions for the specific animal type to estimate 2032
NH3 and VOC emissions.

Table 4-13. National projection factors for livestock: 2018 to 2032

Animal

2018-to-2032

Beef

+0.57%

Swine

+10.54%

Broilers

+17.47%

Turkeys

+3.26%

Layers

+17.24%

Dairy

+0.09%

Overall NH3

+6.39%

Overall VOC

+6.12%

4.2.3.6 Nonpoint Sources (nonpt)

Packets:

Proj ection_2016_2026_all_nonpoint_version2_platform_NC_3 0aug2022_nf_v2

Proj ection_2016_2026_finished_fuels_volpe_l 6jul202 l_v0

Proj ection_2016_2026_industrial_by SCC_version3_platform_09nov2022_vl

Proj ection_2016_2026_nonpt_PFC_version2_platform_MARAMA_noNC_l 6jul202 l_vl

Proj ection_2016_2026_nonpt_other_version3_platform_MARAMA_22aug2022_v0

Proj ection_2016_2026_nonpt_population_version2_platform_noMARAMA_l 6jul202 l_v0

Proj ection_2016_2026_nonpt_version2_platform_NJ_l 6jul202 l_v0

Proj ection_2026_2028_finished_fuels_volpe_l 3aug202 l_v0

Projection_2026_2032_industrial_bySCC_version3_platform_12sep2022_nf_vl

Projection_2026_2032_nonpt_other_ver3_platform_MARAMA_for2032gg_12sep2022_v0

Proj ecti on_2026_2032_nonpt_PF C_version2_platform_M ARAM A_13 aug2021_v0

Projection_2026_2030_nonpt_population_version2_platform_noMARAMA_05aug2021_v0

In 2018v2, emissions sources in the nonpt sectors are based on 2017 NEI, and are projected to 2032 in
two parts. First, base year 2017NEI emissions were projected to 2026 using projection packets developed
for the 2016v3 platform. These projection packets reference 2016 as the base year because they are from
2016v3 platform, but for the nonpt sector in particular, these packets are applicable to the 2017NEI
emissions used in 2018v2 platform. Then, the newly projected 2026 emissions were projected to 2032
emissions using a second set of projection packets in which 2026 is the base year.

Inside MARAMA region

2016-to-2026 and 2026-to-2032 projection packets for all nonpoint sources were provided by MARAMA
for the following states and updated with data from AEO2022: CT, DE, DC, ME, MD, MA, NH, NJ, NY,
NC, PA, RI, VT, VA, and WV. MARAMA provided one projection packet for portable fuel containers

158


-------
(PFCs), and a second projection packet per year for all other nonpt sources. The impacts of these factors
on nonpt emissions other than PFCs are shown in Table 4-14. The impacts of the factors on PFC sources
are shown in Table 4-15.

The MARAMA projection packets were used throughout the MARAMA region, except for 2016-to-2026
projections in North Carolina and New Jersey. Both NC and NJ provided separate projection packets for
the nonpt sector for 2016vl and those projection packets were used instead of the MARAMA packets in
those two states. New Jersey did not provide projection factors for PFCs, and so NJ PFCs were projected
using the MARAMA PFC growth packet. NC- and NJ-provided projection packets were not available for
2032, so MARAMA projection factors were used in those two states beyond 2026. The impacts of the
North Carolina and New Jersey factors from 2016-2026 are shown in Table 4-16 and Table 4-17,
respectively.

Table 4-14. Impact of 2016-2026 factors on nonpt emissions in MARAMA states

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

405,690

410,106

4,416

1.1%

NH3

10,721

10,959

238

2.2%

NOX

183,170

186,704

3,534

1.9%

PM10-PRI

119,049

119,373

324

0.3%

PM25-PRI

106,750

107,056

306

0.3%

S02

22,668

22,028

-640

-2.8%

VOC

107,154

112,662

5,508

5.1%

Table 4-15. Impact of factors on nonpt PFC emissions in MARAMA states

Factor
Years

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

2016-2026

VOC

25,987

26,620

633

2.4%

2026-2032

VOC

20,879

21,112

233

1.1%

Table 4-16. Impact of 2016-2026 factors on nonpt emissions in North Carolina

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

25,506

26,730

1,224

4.8%

NH3

1,196

1,339

143

11.9%

NOX

9,463

10,423

960

10.1%

PM10-PRI

9,326

9,961

635

6.8%

PM25-PRI

8,506

9,087

581

6.8%

S02

418

434

16

3.8%

VOC

16,811

16,214

-597

-3.6%

159


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Table 4-17. Impact of 2016-2026 factors on nonpt emissions in New Jersey

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

19,492

19,924

432

2.2%

NH3

404

395

-9

-2.2%

NOX

22,302

22,544

242

1.1%

PM10-PRI

6,320

6,502

182

2.9%

PM25-PRI

5,759

5,924

165

2.9%

S02

367

367

0

0.0%

VOC

16,934

16,082

-852

-5.0%

Industrial Sources outside MARAMA region

Because each AEO only includes data for one or two years prior to its publication year, projection factors
were developed from by industrial sector using a series of AEOs to cover the period from 2016 through
2032: AEO2018 was used to go from 2016 to 2017; AEO2019 to go from 2017 to 2020; AEO2021 to go
from 2020 to 2021; and AEO2022 to go from 2021 to 2032. SCCs were mapped to AEO categories and
projection factors were created using a ratio between the base year and projection year estimates from
each specific AEO category. For the nonpt sector, only AEO Table 2 was used to map SCCs to AEO
categories for the projections of industrial sources. Depending on the category, a projection factor may be
national or regional. The maximum projection factor was capped at a factor of 2.25 for 2016 to 2026, and
1.75 for 2026 to 2032. Sources within the MARAMA region were not projected with these factors, but
with the MARAMA-provided growth factors. The impacts of these factors on emissions from 2016-2026
and 2025-2032 on nonpt emissions are shown in Table 4-18 and Table 4-19. The impacts of the factors
not associated with SCCs are shown in Table 4-20.

In response to comments, distillate emissions for SCCs 2103004000, 2103004001, and 2103004002 were
held flat with a 1.0 projection factor instead of showing increasing emissions in 2032.

Table 4-18. Impact of 2016-2026 industrial factors by SCC on nonpt emissions in non-MARAMA

states

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

291,269

307,431

16,163

5.5%

NH3

5,122

5,653

530

10.4%

NOX

300,170

319,970

19,800

6.6%

PM10-PRI

146,635

136,472

-10,163

-6.9%

PM25-PRI

97,608

98,086

478

0.5%

S02

128,668

93,840

-34,829

-27.1%

VOC

17,254

18,968

1,714

9.9%

160


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Table 4-19. Impact of 2026-2032 industrial factors by SCC on nonpt emissions in non-MARAMA

states

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

282,178

288,504

6,326

2.2%

NH3

5,653

5,780

128

2.3%

NOX

281,164

286,474

5,310

1.9%

PM10-PRI

136,472

140,194

3,722

2.7%

PM25-PRI

98,086

101,296

3,210

3.3%

S02

93,840

95,261

1,421

1.5%

VOC

18,968

19,298

330

1.7%

Table 4-20. Impact of 2026-2032 factors other than by SCC on nonpt emissions in non-MARAMA

states

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

456,758

457,537

779

0.2%

NH3

12,693

12,624

-70

-0.5%

NOX

218,267

215,622

-2,645

-1.2%

PM10-PRI

135,834

136,607

773

0.6%

PM25-PRI

122,067

122,762

695

0.6%

S02

14,089

13,886

-203

-1.4%

VOC

142,476

139,851

-2,625

-1.8%

Evaporative Emissions from Transport of Finished Fuels outside MARAMA region

Estimates on growth of evaporative emissions from transporting finished fuels are partially covered in the
nonpoint and point oil and gas projection packets. However, there are some processes with evaporative
emissions from storing and transporting finished fuels which are not included in the nonpoint and point
oil and gas projection packets, e.g., withdrawing fuel from tanks at bulk plants, filling tanks at service
stations, etc., and those processes are included in nonpoint other. AEO2018 was used as a starting point
for projecting volumes of finished fuel that would be transported in analytic years. Then these volumes
were used to calculate inventories associated with evaporative emissions in 2016, 2023, and 2028 using
upstream modules in the Emissions Modeling Framework. Those emission inventories were mapped to
the appropriate SCCs and projection packets were generated from 2016 to 2028 using the upstream
modules. For these sources, projection factors for 2028 were applied and the resulting emissions were
used to represent 2032. Sources within the MARAMA region were not projected with these factors, but
with the MARAMA-provided growth factors. The impact of the factors from 2016-2026 and 2026-2028
are shown in Table 4-21.

161


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Table 4-21. Impact of factors on nonpt finished fuel emissions

Factor
years

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

2016-2026

voc

405,952

336,366

-69,586

-17.1%

2026-2028

voc

336,366

317,038

-19,327

-5.7%

Human Population Growth outside MARAMA region

For SCCs that were projected based on human population growth, population projection data were
available from the Benefits Mapping and Analysis Program (BenMAP) model by county for several
years, including 2017, 2025, and 2030. These human population data were used to create modified
county-specific projection factors. The impacted SCCs are shown in Table 4-22. Note that 2017 is being
used as the base year since 2016 human population is not available in this dataset. A newer human
population dataset was assessed but it did not have realistic population projections through the 2020s, and
was therefore not used. For example, rural areas of NC were projected to have more growth than urban
areas, which is the opposite of what has happened in recent years. Growth factors were limited to 5%
cumulative annual growth (e.g. 35% annual growth over 7 years), but none of the factors fell outside that
range. For these population-based projection factors, 2030 population was used to represent 2032.

Sources within the MARAMA region were not projected with these factors, but with the MARAMA-
provided growth factors. The impact of the population growth-based factors on the nonpt emissions is
shown in Table 4-23 and Table 4-24.

Table 4-22. SCCs in nonpt that use Human Population Growth for Projections

see

Description

2302002100

Industrial Processes;Food and Kindred Products: SIC 20;Commercial Cooking -
Charbroiling; Conveyorized Charbroiling

2302002200

Industrial Processes;Food and Kindred Products: SIC 20;Commercial Cooking -
Charbroiling;Under-fired Charbroiling

2302003000

Industrial Processes;Food and Kindred Products: SIC 20;Commercial Cooking - Frying;Deep
Fat Frying

2302003100

Industrial Processes;Food and Kindred Products: SIC 20;Commercial Cooking - Frying;Flat
Griddle Frying

2302003200

Industrial Processes;Food and Kindred Products: SIC 20;Commercial Cooking -
Frying;Clamshell Griddle Frying

2501011011

Storage and Transport;Petroleum and Petroleum Product Storage;Residential Portable Gas
Cans;Permeation

2501011012

Storage and Transport;Petroleum and Petroleum Product Storage;Residential Portable Gas
Cans;Evaporation (includes Diurnal losses)

2501011013

Storage and Transport;Petroleum and Petroleum Product Storage;Residential Portable Gas
Cans;Spillage During Transport

2501011014

Storage and Transport;Petroleum and Petroleum Product Storage;Residential Portable Gas
Cans;Refilling at the Pump - Vapor Displacement

2501011015

Storage and Transport;Petroleum and Petroleum Product Storage;Residential Portable Gas
Cans;Refilling at the Pump - Spillage

2501012011

Storage and Transport;Petroleum and Petroleum Product Storage;Commercial Portable Gas
Cans;Permeation

2501012012

Storage and Transport;Petroleum and Petroleum Product Storage;Commercial Portable Gas
Cans;Evaporation (includes Diurnal losses)

162


-------
see

Description

2501012013

Storage and Transport;Petroleum and Petroleum Product Storage;Commercial Portable Gas
Cans;Spillage During Transport

2501012014

Storage and Transport;Petroleum and Petroleum Product Storage;Commercial Portable Gas
Cans;Refilling at the Pump - Vapor Displacement

2501012015

Storage and Transport;Petroleum and Petroleum Product Storage;Commercial Portable Gas
Cans;Refilling at the Pump - Spillage

2630020000

Waste Disposal, Treatment, and Recovery;Wastewater Treatment;Public Owned;Total
Processed

2640000000

Waste Disposal, Treatment, and Recovery;TSDFs;All TSDF Types;Total: All Processes

2810025000

Miscellaneous Area Sources;Other Combustion;Residential Grilling (see 23-02-002-xxx for
Commercial) ;Total

2810060100

Miscellaneous Area Sources;Other Combustion;Cremation;Humans

Table 4-23. Impact of 2016-2026 population-based factors on nonpt emissions in non-MARAMA

states

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

105,731

117,336

11,605

11.0%

NH3

1,555

1,707

152

9.8%

NOX

1,747

1,942

195

11.2%

PM10-PRI

90,772

100,389

9,617

10.6%

PM25-PRI

83,068

91,860

8,792

10.6%

S02

92

102

9

10.3%

VOC

64,056

70,658

6,603

10.3%

Table 4-24. Impact of 2026-2030 population-based factors on nonpt emissions in non-MARAMA

states

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

117,336

121,978

4,641

4.0%

NH3

1,707

1,768

61

3.6%

NOX

1,942

2,020

78

4.0%

PM10-PRI

100,389

104,236

3,847

3.8%

PM25-PRI

91,860

95,377

3,517

3.8%

S02

102

105

4

3.7%

VOC

70,658

73,299

2,641

3.7%

163


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4.2.3.7 Solvents (np_solvents)

Packets:

Proj ection_2016_202X_solvents_v3platform_Idaho_asphalt_09aug2022_v0
Projection_2018_2032_np_solvents_for_2032gg_MARAMA_14sep2022_v0
Proj ection_2018_2030_np_solvents_for_2032gg_noMARAMA_l 3 sep2022_v0

The projection methodology for npsolvents is similar to the method used in the 2016v3 platform.
Projection factors from MARAMA were applied inside the MARAMA region, and projection factors
based on human population trends are applied for most solvent categories elsewhere. All of these packets
were checked to confirm they cover all SCCs in the solvents sector, and packets were supplemented with
additional SCCs as needed, copied from factors for existing SCCs. The SCCs in np solvents that are
projected using human population growth are shown in Table 4-25.

The following updates were made starting in 2016v3 platform to supplement the SCCs included in the
projection packets:

all 2460- SCCs and 2402000000 use human population (copied from an existing 2460- SCC);

most surface coating and graphic arts SCCs use either human population (MARAMA and non-
MARAMA regions) or employment data (some SCCs in MARAMA region only);

added new SCC 2460030999 (lighter fluid) to project based on human population in all regions.

For 2016v3, Idaho asphalt emissions (SCCs = 2461021000, 2461022000) were reduced by 14.2% based
on a comment from the state. The impact of the population-based factors on the np solvents sector
emissions outside of MARAMA states are shown in Table 4-26. The impacts of the factors on
np_solvents emissions in MARAMA states are shown in Table 4-27.

Table 4-25. SCCs in np solvents that use Human Population Growth for Projections

SCC

SCC Descriptions

2401001000

Solvent Utilization;Surface Coating: Architectural Coatings;Total: All Solvent Types

2401005000

Solvent Utilization;Surface Coating;Auto Refinishing: SIC 7532;Total: All Solvent Types

2401005700

Solvent Utilization;Surface Coating;Auto Refinishing: SIC 7532;Top Coats

2401008000

Solvent Utilization;Surface Coating;Traffic Markings;Total: All Solvent Types

2401010000

Solvent Utilization;Surface Coating;Textile Products: SIC 22;Total: All Solvent Types

2401015000

Solvent Utilization;Surface Coating;Factory Finished Wood: SIC 2426 thru 242;Total: All Solvent Types

2401020000

Solvent Utilization;Surface Coating;Wood Furniture: SIC 25;Total: All Solvent Types

2401025000

Solvent Utilization;Surface Coating;Metal Furniture: SIC 25;Total: All Solvent Types

2401030000

Solvent Utilization;Surface Coating;Paper: SIC 26;Total: All Solvent Types

2401035000

Solvent Utilization;Surface Coating;Plastic Products: SIC 308;Total: All Solvent Types

2401040000

Solvent Utilization;Surface Coating;Metal Cans: SIC 341;Total: All Solvent Types

2401045000

Solvent Utilization;Surface Coating;Metal Coils: SIC 3498;Total: All Solvent Types

2401050000

Solvent Utilization;Surface Coating;Miscellaneous Finished Metals: SIC 34 - (341 + 3498);Total: All
Solvent Types

2401055000

Solvent Utilization;Surface Coating;Machinery and Equipment: SIC 35;Total: All Solvent Types

2401060000

Solvent Utilization;Surface Coating;Large Appliances: SIC 363;Total: All Solvent Types

2401065000

Solvent Utilization;Surface Coating;Electronic and Other Electrical: SIC 36 - 363;Total: All Solvent Types

164


-------
see

SCC Descriptions

2401070000

Solvent Utilization;Surface Coating;Motor Vehicles: SIC 371;Total: All Solvent Types

2401075000

Solvent Utilization;Surface Coating;Aircraft: SIC 372;Total: All Solvent Types

2401080000

Solvent Utilization;Surface Coating;Marine: SIC 373;Total: All Solvent Types

2401085000

Solvent Utilization;Surface Coating;Railroad: SIC 374;Total: All Solvent Types

2401090000

Solvent Utilization;Surface Coating:Miscellaneous Manufacturing;Total: All Solvent Types

2401100000

Solvent Utilization;Surface Coating:Industrial Maintenance Coatings;Total: All Solvent Types

2401200000

Solvent Utilization;Surface Coating;Other Special Purpose Coatings;Total: All Solvent Types

2425000000

Solvent Utilization;Graphic Arts;All Processes;Total: All Solvent Types

2425020000

Solvent Utilization;Graphic Arts;Letterpress;Total: All Solvent Types

2425030000

Solvent Utilization;Graphic Arts;Rotogravure;Total: All Solvent Types

2440000000

Solvent Utilization;Miscellaneous Industrial;All Processes;Total: All Solvent Types

2440020000

Solvent Utilization;Miscellaneous Industrial;Adhesive (Industrial) Application;Total: All Solvent Types

2460030999

Solvent Utilization;Miscellaneous Non-industrial: Consumer and Commercial;Lighter Fluid, Fire Starter,
Other Fuels;Total: All Volatile Chemical Product Types

2460100000

Solvent Utilization;Miscellaneous Non-industrial: Consumer and Commercial;All Personal Care
Products;Total: All Solvent Types

2460200000

Solvent Utilization;Miscellaneous Non-industrial: Consumer and Commercial;All Household Products;Total:
All Solvent Types

2460400000

Solvent Utilization;Miscellaneous Non-industrial: Consumer and Commercial;All Automotive Aftermarket
Products;Total: All Solvent Types

2460500000

Solvent Utilization;Miscellaneous Non-industrial: Consumer and Commercial;All Coatings and Related
Products;Total: All Solvent Types

2460600000

Solvent Utilization;Miscellaneous Non-industrial: Consumer and Commercial;All Adhesives and
Sealants;Total: All Solvent Types

2460800000

Solvent Utilization;Miscellaneous Non-industrial: Consumer and Commercial;All FIFRA Related
Products;Total: All Solvent Types

2460900000

Solvent Utilization;Miscellaneous Non-industrial: Consumer and Commercial;Miscellaneous Products (Not
Otherwise Covered);Total: All Solvent Types

2461800001

Solvent Utilization;Miscellaneous Non-industrial: Commercial;Pesticide Application: All Processes;Surface
Application

Table 4-26. Impact of population-based factors on np solvents emissions in non-MARAMA states

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

15

17

3

17.7%

NH3

58

65

7

12.6%

NOX

27

32

5

17.9%

PM10-PRI

450

508

58

12.9%

PM25-PRI

429

484

55

12.8%

S02

1

1

0

18.2%

VOC

1,435,256

1,613,518

178,262

12.4%

165


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Table 4-27. Impact of factors on npsolvents emissions in MARAMA states

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

voc

565,443

595,664

30,221

5.3%

4.2.3.8 Oil and Gas Sources (np_oilgas, pt_oilgas)

Packets:

Proj ection_2018_2032_np_oilgas_for_2032gg_21 sep2022_v0
Proj ection_2018_2032_pt_oilgas_for_2032gg_22sep2022_v0

Analytic year projections for the 2018v2 platform were generated for point oil and gas sources for the
year 2032. This projection consisted of three components: (1) applying facility closures to the ptoilgas
sector using the CoST CLOSURE packet (see Section 4.2.4); (2) using historical and/or forecast activity
data to generate analytic-year emissions before applicable control technologies are applied using the
CoST PROJECTION packet; and (3) estimating impacts of applicable control technologies on analytic-
year emissions using the CoST CONTROL packet. Applying the CLOSURE packet to the pt oilgas
sector resulted in small emissions changes to the national summary shown in Table 4-5.

For pt oilgas growth to 2032, the oil and gas sources were separated into production-related and pipeline-
related sources by NAICS and SCC. These sources were further subdivided by fuel-type and by NAICS
and SCC into either OIL, natural gas (NGAS), or BOTH (where oil or natural gas fuels are possible). The
next two subsections describe the growth component of the process.

For npoilgas growth to 2032, oil and gas sources were separated into production-related and exploration-
related sources. These sources were further separated into oil, natural gas or coal bed methane production
related.

Production-related Sources (pt oilgas, np oilgas)

The growth factors for the production-related NAICS-SCC combinations were generated in a two-step
process. The first step used historical production data at the state-level to get state-level short-term trends
or factors from 2018 to year 2021. These historical data were acquired from EIA from the following links:

•	Historical Natural Gas: http://www.eia.gov/dnav/ng/ng sum lsum a epgO fgw mmcf a.htm

•	Historical Crude Oil: http://www.eia.gov/dnav/pet/pet crd crpdn adc mbbl a.htm

•	Historical CBM: https://www.eia.gov/dnav/ng/ng prod coalbed si a.htm

The second step involved using the Annual Energy Outlook (AEO) 2022 reference case for the Lower 48
forecast production tables to project from the year 2021 to the year of 2032. Specifically, AEO 2022 Table
58 "Lower 48 Crude Oil Production and Wellhead Prices by Supply Region " and AEO 2022 Table 59
"Lower 48 Natural Gas Production and Supply Prices by Supply Region " were used in this projection
process. The AEO2022 forecast production is supplied for each EIA Oil and Gas Supply region shown in
Figure 4-1.

166


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Figure 4-1. EIA Oil and Gas Supply Regions as of AEO2022

Pacific

The result of this second step is a growth factor for each Supply Region from 2021 to 2032. A Supply
Region mapping to FIPS cross-walk was developed so the regional growth factors could be applied for
each FIPS (for pt_oilgas) or to the county-level np_oilgas inventories. Note that portions of Texas are in
three different Supply Regions and portions of New Mexico are in two different supply regions. The state-
level historical factor (from 2018 to 2021) was then multiplied by the Supply Region factor (from 2021 to
the analytic years) to produce a state-level or FlPS-level factor to grow from 2018 to 2032. This process
was done using crude production forecast information to generate a factor to apply to oil-production
related SCCs or NAICS-SCC combinations and it was also done using natural gas production forecast
information to generate a factor to apply to natural gas-production related NAICS-SCC combinations. For
the SCC and NAICS-SCC combinations that are designated "BOTH" the average of the oil-production
and natural-gas production factors was calculated and applied to these specific combinations.

The state of Texas provided specific comments on the growth of production-related point sources. Texas
provided updated basin specific production for 2018 and 2021 to allow for a better calculation of the
estimated growth for this three-year period (http://webapps.rrc.texas.gov/PDO/generalReportAction.do).
The AEO2022 was used as described above for the three AEO Oil and Gas Supply Regions that include
Texas counties to grow from 2021 to 2032. However, Texas only wanted these growth factors applied to
sources in the Permian and Eagle Ford basins and the oil and gas production point sources in the other
basins in Texas were not grown.

The state of New Mexico is broken up into two AEO Oil and Gas Supply Regions. County production
data for New Mexico was obtained from their state website

(https://wwwapps.emnrd.nm.gov/ocd/ocdpermitting/Reporting/Production/CountvProductionIniectionSu
mmarv.aspx ) so that a better estimate of growth from 2018 to 2021 for the AEO Supply Regions in New
Mexico could be calculated.

167


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Transmission-related Sources (ptoilgas)

Projection factors for transmissions-related sources were generated using the same AEO2022 tables used
for production sources. These growth factors sources were developed solely using AEO 2022 data for the
entire lower 48 states (one national factor for oil transmission and one national factor for natural gas
transmission). The 2018-to-2032 growth for oil transmission was +21.2%, and the growth for natural gas
was +28.0%. The impact of the projection factors on the pt oilgas emissions is shown in Table 4-28.

Table 4-28. Impact of 2018-2032 projections on pt oilgas emissions

Pollutant

Inventory Emissions

Final Emissions

Emissions Change

Emissions % Change

CO

166,667

181,220

14,553

8.7%

NH3

365

283

-82

-22.5%

NOX

338,206

397,481

59,276

17.5%

PM10-PRI

11,400

12,705

1,305

11.4%

PM25-PRI

10,844

12,029

1,186

10.9%

S02

32,881

42,055

9,174

27.9%

VOC

209,368

218,922

9,554

4.6%

Exploration-related Sources (npoilgas)

Years 2017 through 2019 exploration emissions were generated using the 2017NEI version of the Oil and
Gas Tool. Table 4-29 provides a high-level national summary of the emissions data for the three years.
This three-year average (2017-2019) emissions data were used in 2018v2 because they reflected the most
recent average of exploration activity and emissions. These averaged emissions were used for the 2032
analytic year. Note that CoST was not used to perform this projection step for exploration sources, but is
used to apply controls to exploration sources for 2032. The change in emissions from 2018 to 2032 due to
the impact of the projections is shown in Table 4-30.

Table 4-29. Year 2017-2019 high-level summary of national oil and gas exploration emissions

Pollutant

2017
emissions

2018
emissions

2019
emissions

Three Year avg
(2017-2019) (tons)

NOX

73,992

123,908

108,957

102,285

VOC

118,004

136,916

106,505

120,474

Table 4-30. Impact of 2018-2032 projections on np oilgas emissions

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

518,419

561,343

42,924

8.3%

NH3

7

2

-5

-71.9%

NOX

382,846

417,535

34,690

9.1%

PM10-PRI

7,177

7,503

326

4.5%

PM25-PRI

7,114

7,440

326

4.6%

S02

48,690

69,946

21,256

43.7%

VOC

1,920,896

2,209,159

288,264

15.0%

168


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4.2.3.1 Non-EGU point sources (ptnonipm)

Packets:

Proj ection_2026_2028_finished_fuels_volpe_l 3aug202 l_vO

Projection_2026_2032_industrial_byNAICS_SCC_version3_platform_22sep2022_v0
Projection_2026_2032_industrial_bySCC_version3_platform_12sep2022_nf_vl
Proj ection_2026_2032_ptnonipm_version2_platform_MARAMA_l 3aug202 l_vO
proj ection_2026_2028_corn_ethanol_E0B0_V olpe_l 3 aug202 l_vO

Projections to 2032 ptnonipm start with the year 2026 emissions from the 2016v3 platform and are
additionally projected to 2032. In 2016v3 platform, emissions for the 2023 ptnonipm sector were set equal
to emissions from the 2019 NEI point source emissions file dated March 25, 2022. This inventory was
projected to 2026 as part of 2016v3 platform, and then for 2018v2 platform, projected further into 2032.
This section describes the projections applied from 2026 to 2032. Details on projected ptnonipm
emissions through 2026 are available in the 2016v3 TSD.

The 2032 ptnonipm emissions were projected from the 2016v3 platform year 2026 point source emissions
using several growth and projection methods described as here. The projection of oil and gas sources is
explained in the oil and gas section.

2032 Point Inventory - inside MARAMA region

2026-to-2032 projection packets for point sources were based on the projection factors provided by
MARAMA for the following states: CT, DE, DC, ME, MD, MA, NH, NJ, NY, NC, PA, RI, VT, VA, and
WV. The factors were developed using the MARAMA projection tool and by selecting 2026 for the base
year and 2032 for the projection year. Unlike in 2016v3 platform, additional projection packets were not
used in North Carolina, New Jersey, and Virginia, because those projection packets (originally provided
for 2016vl platform) do not extend beyond 2028. Instead, 2026-to-2032 projections in those three states
are based on the MARAMA projection tool. The impact of the MARAMA projection packet on ptnonipm
emissions from 2026 to 2032 is shown in Table 4-31.

Table 4-31. Impact of 2026-2032 MARAMA projections on ptnonipm emissions

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

97,728

99,785

2,057

2.1%

NH3

6,273

6,315

43

0.7%

NOX

88,133

89,211

1,077

1.2%

PM10-PRI

33,474

33,693

220

0.7%

PM25-PRI

23,681

23,874

192

0.8%

S02

50,072

50,021

-50

-0.1%

VOC

77,226

77,425

198

0.3%

169


-------
2032 Point Inventories - outside MARAMA region

Projection factors were developed by industrial sector from AEO 2022 in order to project emissions from
2026 to 2032. Emissions were mapped to AEO categories by NAICS and SCC (combination of NAICS
and SCC first, SCC only after that) and projection factors were created using a ratio between the base year
and projection year estimates from each specific AEO category. SCC/NAICS combinations with
emissions >100tons/year for any CAP26 were mapped to AEO sector and fuel. Table 4-32 below details
the AEO2022 tables used to map SCCs to AEO categories for the projections of industrial sources. The
impact of the projection packets specified by NAICS and SCC from 2026-2032 is shown in Table 4-33
and the impact of the projection packets specified by SCC is shown in Table 4-34.

Table 4-32. Annual Energy Outlook (AEO) 2022 tables used to project industrial sources

AEO 2022 Table #

AEO Table name

2

Energy Consumption by Sector and Source

24

Refining Industry Energy Consumption

25

Food Industry Energy Consumption

26

Paper Industry Energy Consumption

27

Bulk Chemical Industry Energy Consumption

28

Glass Industry Energy Consumption

29

Cement Industry Energy Consumption

30

Iron and Steel Industries Energy Consumption

31

Aluminum Industry Energy Consumption

32

Metal Based Durables Energy Consumption

33

Other Manufacturing Sector Energy Consumption

34

Nonmanufacturing Sector Energy Consumption

Table 4-33. Impact of 2026-2032 industrial projections by NAICS and SCC on ptnonipm emissions

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

179,673

182,335

2,663

1.5%

NH3

2,697

2,761

63

2.3%

NOX

174,429

177,552

3,123

1.8%

PM10-PRI

27,752

28,660

909

3.3%

PM25-PRI

23,822

24,512

690

2.9%

S02

70,516

70,769

252

0.4%

VOC

12,296

12,662

367

3.0%

26 The "100 tpy" criterion for this purpose was based on emissions in the emissions values in the 2016 beta platform.

170


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Table 4-34. Impact of 2026-2032 industrial projections by SCC on ptnonipm emissions

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

464,198

476,609

12,411

2.7%

NH3

4,213

4,398

185

4.4%

NOX

321,324

333,674

12,349

3.8%

PM10-PRI

66,072

68,580

2,509

3.8%

PM25-PRI

47,440

49,148

1,708

3.6%

S02

99,096

104,118

5,023

5.1%

VOC

34,460

35,771

1,311

3.8%

Finished fuel and biorefinery factors

Factors were developed as part of the 2016 platform to project finished fuels and biorefineries to analytic
years. Estimates on growth of evaporative emissions from transporting finished fuels are not covered as
part of oil and gas projections, e.g., withdrawing fuel from tanks at bulk plants, filling tanks at service
stations, etc. For 2016vl platform, the AEO 2018 was used as a starting point for projecting volumes of
finished fuel that would be transported in the analytic years of 2023 and 2028. Then these volumes were
used to calculate inventories associated with evaporative emissions in 2016, 2023, and 2028 using the
upstream modules. Those emission inventories were mapped to the appropriate SCCs and projection
packets were generated using the upstream modules. Because the last analytic year available for the
2016vl platform was 2028, it was not possible to develop factors specific to 2032. Instead, the portion of
the factors effective from 2026 to 2028 were applied for this study and the resulting emissions were held
constant at 2028 levels. A set of 2026-to-2028 projection factors was interpolated from the 2023 and 2028
projection factors from 2016vl platform. Sources within the MARAMA region were projected with
MARAMA-provided growth factors. The impact of the finished fuels factors on ptnonipm emissions is
shown in Table 4-35 and the impact on biorefinery emissions is shown in Table 4-36.

Table 4-35. Impact of 2026-2028 factors on ptnonipm finished fuel emissions

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

VOC

13,936

13,092

-843

-6.1%

Table 4-36. Impact of 2026-2028 factors on ptnonipm biorefinery emissions

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

Emissions %
Change

CO

7,473

7,332

-141

-1.9%

NH3

297

291

-6

-1.9%

NOX

10,197

10,004

-192

-1.9%

PM10-PRI

5,659

5,552

-107

-1.9%

PM25-PRI

4,529

4,444

-85

-1.9%

S02

3,591

3,523

-68

-1.9%

VOC

13,708

13,449

-259

-1.9%

171


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4.2.3.2 Railroads (rail)

Packets:

Proj ection_2026_2032_rail_for_2032gg_23 sep2022_v0

The starting point for the 2032 rail emissions were the 2026 emissions from the 2016v3 platform. Those
emissions were projected from 2026 to 2032 based on AEO2022 growth rates as shown in Table 4-37.

Table 4-37. AEO2022 growth rates for rail sub-groups, 2026 to 2032

Sector

Pollutant

2032

Class I Railroads

NOx

-15.7%

Class I Railroads

PM

-22.9%

Class I Railroads

VOC

-27.3%

Class I Railroads

Others

+0.99%

Class II/III Railroads

All

+0.99%

Commuter/Passenger

All

+14.3%

Rail Yards

All

+0.99%

For 2018v2, CARB provided new locomotive emissions for 2032. For VOC speciation, the EPA preferred
augmenting the 2032 CARB inventory (which only included CAPs) with HAPs and using those HAPs for
integration, rather than running the California portion of the sector as no-integrate. In addition to updating
the nonpoint rail inventory in California, the point rail yard emissions in ptnonipm were also updated to
better reflect the new rail yard emissions in the California rail inventory. The overall impact of all
projections on the rail emissions are shown in Table 4-38.

Table 4-38. Impact of projections on rail emissions

Pollutant

2026
Emissions

2032
Emissions

Emissions
Change

CO

107,420

109,034

1,615

NH3

335

340

5.0

NOX

465,183

413,468

-51,715

PM10-PRI

12,460

10,429

-2,032

PM25-PRI

12,084

10,114

-1,977

S02

379

384

5.7

VOC

20,621

16,770

-3,851

4.2.3.3 Residential Wood Combustion (rwc)

Packets:

Proj ection_2017_2032gg_rwc_fromMARAMA_12sep2022_v0

For residential wood combustion, the growth and control factors are computed together into merged
factors in the same packet. Emissions for the states of California, Oregon, and Washington are held

172


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constant due to regulations in effect in those areas. For the remaining states, RWC emissions from
2017NEI were projected to 2032 using projection factors derived using the MARAMA tool that is based
on the projection methodology from EPA's 201 lv6.3 platform. The year 2017 was used to represent
2018. The development of projected growth in RWC emissions to year 2032 is based on the projected
growth in RWC appliances derived from year 2012 appliance shipments reported in the Regulatory
Impact Analysis (RIA) for Proposed Residential Wood Heaters NSPS Revision Final Report available at:
http://www2.epa.gov/sites/production/files/2013-12/documents/ria-20140103.pdf. The 2012 shipments
are based on 2008 shipment data and revenue forecasts from a Frost & Sullivan Market Report (Frost &
Sullivan, 2010). Next, to be consistent with the RIA, growth rates for new appliances for certified wood
stoves, pellet stoves, indoor furnaces and OHH were based on forecasted revenue (real GDP) growth rate
of 2.0% per year from 2013 through 2025 as predicted by the U.S. Bureau of Economic Analysis (BEA,
2012). While this approach is not perfectly correlated, in the absence of specific shipment projections, the
RIA assumes the overall trend in the projection is reasonable. All of the factors in the projection tool are
held constant with no additional changes after year 2025. The growth rates for appliances not listed in the
RIA (fireplaces, outdoor wood burning devices (not elsewhere classified) and residential fire logs) are
estimated based on the average growth in the number of houses between 2002 and 2012, about 1% (U.S.
Census, 2012).

In addition to new appliance sales and forecasts extrapolating beyond 2012, assumptions on the
replacement of older, existing appliances are needed. Based on long lifetimes, no replacement of
fireplaces, outdoor wood burning devices (not elsewhere classified) or residential fire logs is assumed. It
is assumed that 95% of new woodstoves will replace older non-EPA certified freestanding stoves (pre-
1988 NSPS) and 5% will replace existing EPA-certified catalytic and non-catalytic stoves that currently
meet the 1988 NSPS (Houck, 2011).

Equation 4-1 was applied with RWC-specific factors from the rule. EPA RWC NSPS experts assume that
10%) of new pellet stoves and OHH replace older units and that because of their short lifespan, that 10%>
of indoor furnaces are replaced each year. The resulting growth factors for these appliance types varies by
appliance type and also by pollutant because the emission rates, from the EPA RWC tool (EPA,

2013rwc), vary by appliance type and pollutant. For EPA certified units, the projection factors for PM are
lower than those for all other pollutants. The projection factors also vary because the total number of
existing units in 2016 varies greatly between appliance types.

Table 4-39 contains the factors to adjust the emissions from 2017 to 2032 outside of California, Oregon,
and Washington, where RWC emissions were held constant at 2017 NEI levels for the years 2017 and
2032 due to the unique control programs that those states have in place. Table 4-40 shows the overall
impact of projection on the sector.

Table 4-39. Projection factors for Residential Wood Combustion

see

SCC description

Pollutant*

2017-to-2032

2104008100

Fireplace: general



+15.36%

2104008210

Woodstove: fireplace inserts; non-EPA certified



-16.50%

2104008220

Woodstove: fireplace inserts; EPA certified; non-catalytic

PM10-PRI

+3.92%

2104008220

Woodstove: fireplace inserts; EPA certified; non-catalytic

PM25-PRI

+3.92%

2104008220

Woodstove: fireplace inserts; EPA certified; non-catalytic



+7.60%

2104008230

Woodstove: fireplace inserts; EPA certified; catalytic

PM10-PRI

+6.41%

2104008230

Woodstove: fireplace inserts; EPA certified; catalytic

PM25-PRI

+6.41%

173


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see

SCC description

Pollutant*

2017-to-2032

2104008230

Woodstove

fireplace inserts; EPA certified; catalytic



+12.47%

2104008310

Woodstove

freestanding, non-EPA certified

CO

-14.70%

2104008310

Woodstove

freestanding, non-EPA certified

PM10-PRI

-15.58%

2104008310

Woodstove

freestanding, non-EPA certified

PM25-PRI

-15.58%

2104008310

Woodstove

freestanding, non-EPA certified

VOC

-13.94%

2104008310

Woodstove

freestanding, non-EPA certified



-14.70%

2104008320

Woodstove

freestanding, EPA certified, non-catalytic

PM10-PRI

+3.92%

2104008320

Woodstove

freestanding, EPA certified, non-catalytic

PM25-PRI

+3.92%

2104008320

Woodstove

freestanding, EPA certified, non-catalvtic



+7.60%

2104008330

Woodstove

freestanding, EPA certified, catalytic

PM10-PRI

+6.41%

2104008330

Woodstove

freestanding, EPA certified, catalytic

PM25-PRI

+6.41%

2104008330

Woodstove

freestanding, EPA certified, catalytic



+12.47%

2104008400

Woodstove

pellet-fired, general (freestanding or FP insert)

PM10-PRI

+29.85%

2104008400

Woodstove

pellet-fired, general (freestanding or FP insert)

PM25-PRI

+29.85%

2104008400

Woodstove

pellet-fired, general (freestanding or FP insert)



+25.94%

2104008510

Furnace: Indoor, cordwood-fired, non-EPA certified

CO

-83.91%

2104008510

Furnace: Indoor, cordwood-fired, non-EPA certified

PM10-PRI

-82.31%

2104008510

Furnace: Indoor, cordwood-fired, non-EPA certified

PM25-PRI

-82.31%

2104008510

Furnace: Indoor, cordwood-fired, non-EPA certified

VOC

-84.03%

2104008510

Furnace: Indoor, cordwood-fired, non-EPA certified



-83.91%

2104008530

Furnace: Indoor, pellet-fired, general

PM10-PRI

+29.85%

2104008530

Furnace: Indoor, pellet-fired, general

PM25-PRI

+29.85%

2104008530

Furnace: Indoor, pellet-fired, general



+25.94%

2104008610

Hydronic heater: outdoor

PM10-PRI

-1.83%

2104008610

Hydronic heater: outdoor

PM25-PRI

-1.83%

2104008610

Hydronic heater: outdoor



-2.26%

2104008620

Hydronic heater: indoor

PM10-PRI

-1.83%

2104008620

Hydronic heater: indoor

PM25-PRI

-1.83%

2104008620

Hydronic heater: indoor



-2.26%

2104008630

Hydronic heater: pellet-fired

PM10-PRI

-1.83%

2104008630

Hydronic heater: pellet-fired

PM25-PRI

-1.83%

2104008630

Hydronic heater: pellet-fired



-2.26%

2104008700

Outdoor wood burning device, NEC (fire-pits, chimineas, etc)



+8.19%

2104009000

Fire log total



+8.19%

* If no pollutant is specified, facture is used for any pollutants that do not have a pollutant-specific factor

Table 4-40. Impact of projections on rwc emissions, 2017-2032

Pollutant

Inventory
Emissions

Final
Emissions

Emissions
Change

CO

2,317,024

2,259,199

-57,826

NH3

16,426

16,146

-280

NOX

37,382

38,599

1,217

PM10-PRI

301,157

291,135

-10,022

PM25-PRI

299,911

289,966

-9,945

S02

8,503

7,687

-816

VOC

319,313

313,588

-5,724

174


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4.2.4 CoST CONTROL Packets (nonpt, np_oilgas, ptnonipm, pt_oilgas,
np_sol vents)

The final step in the projection of emissions to an analytic year is the application of any control
technologies or programs. For analytic-year New Source Performance Standards (NSPS) controls (e.g.,
oil and gas, Reciprocating Internal Combustion Engines (RICE), Natural Gas Turbines, and Process
Heaters), we attempted to control only new sources/equipment using the following equation to account for
growth and retirement of existing sources and the differences between the new and existing source
emission rates.

Qn = Qo { [ (1 + Pf) t-l]Fn + (l-Ri)tFe + [l-(l-Ri)t]Fn]}	Equation 4-1

where:

Qn = emissions in projection year
Qo = emissions in base year

Pf = growth rate expressed as ratio (e.g., 1.5=50 percent cumulative growth)
t = number of years between base and analytic years
Fn = emission factor ratio for new sources

Ri = retirement rate, expressed as whole number (e.g., 3.3 percent=0.033)

Fe = emission factor ratio for existing sources

The first term in Equation 4-1 represents new source growth and controls, the second term accounts for
retirement and controls for existing sources, and the third term accounts for replacement source controls.
For computing the CoST % reductions (Control Efficiency), the simplified Equation 4-2 was used for
analytic year projections:

Control. EfRctency2o2*(%) = 100 x ¦

[tP/2a2*-i)xFH+(i-si}12+fi-(i-Hi)12)xFnl\	Equation 4-2

PflOZX	/

For example, to compute the control efficiency for 2032 from a base year of 2018 the existing source
emissions factor (Fe) is set to 1.0; 2032 (the analytic year) minus 2018 (the base year) is 14, and the new
source emission factor (Fn) is the ratio of the NSPS emission factor to the existing emission factor.

The NSPS are applied to sectors and with the specified retirement rates (R) as follows:

•	The Oil and Gas NSPS is applied to the npoilgas and ptoilgas sectors with no assumed
retirement rate.

•	The RICE NSPS is applied to the np oilgas, pt oilgas, nonpt, and ptnonipm sectors with an
assumed retirement rate of 40 years (2.5%).

•	The Gas Turbines NSPS is applied to the pt oilgas and ptnonipm sectors with an assumed
retirement rate of 45 years (2.2%).

•	The Process Heaters NSPS is applied to the pt oilgas and ptnonipm sectors with an assumed
retirement rate of 30 years (3.3%).

175


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Table 4-41 shows the values for the emission factors for new sources (Fn) with respect to each NSPS
regulation and other conditions within. Further information about the application of NSPS controls can be
found in Section 4 of the Additional Updates to Emissions Inventories for the Version 6.3, 2011
Emissions Modeling Platform for the Year 2023 technical support document (EPA, 2017).

Table 4-41. Assumed new source emission factor ratios for NSPS rules

NSPS

Pollutants

Applied where?

New Source
Emission Factor (Fn)

Oil and Gas

VOC

Storage Tanks: 70.3% reduction in growth-only
(>1.0)

0.297

Oil and Gas

VOC

Gas Well Completions: 95% control (regardless)

0.05

Oil and Gas

VOC

Pneumatic controllers, not high-bleed >6scfm or

0.23

low-bleed: 77% reduction in growth-only (>1.0)

Oil and Gas

VOC

Pneumatic controllers, high-bleed >6scfm or low-
bleed: 100% reduction in growth-only (>1.0)

0.00

Oil and Gas

VOC

Compressor Seals: 79.9% reduction in growth-
only (>1.0)

0.201

Oil and Gas

VOC

Fugitive Emissions: 60% Valves, flanges,
connections, pumps, open-ended lines, and other

0.40

RICE

NOx

Lean burn: PA, all other states

0.25, 0.606

RICE

NOx

Rich Burn: PA, all other states

0.1, 0.069

RICE

NOx

Combined (average) LB/RB: PA, other states

0.175, 0.338

RICE

CO

Lean burn: PA, all other states

1.0 (n/a), 0.889

RICE

CO

Rich Burn: PA, all other states

0.15, 0.25

RICE

CO

Combined (average) LB/RB: PA, other states

0.575, 0.569

RICE

VOC

Lean burn: PA, all other states

0.125, n/a

RICE

VOC

Rich Burn: PA, all other states

0.1,n/a

RICE

VOC

Combined (average) LB/RB: PA, other states

0.1125, n/a

Gas Turbines

NOx

California and NOx SIP Call states

0.595

Gas Turbines

NOx

All other states

0.238

Process Heaters

NOx

Nationally to Process Heater SCCs

0.41

4.2.4.1 Oil and Gas NSPS (np_oilgas, pt_oilgas)

Packets:

Control_2018_2032_Oilgas_NSP S_withNMrule_np_oilgas_for_2032gg_21 sep2022_v0
Control_2018_2032_Oilgas_NSPS_withNMrule_pt_oilgas_for_2032gg_21 sep2022_v0

New packets to reflect the oil and gas NSPS were developed for the 2018 platform. For oil and gas NSPS
controls, except for gas well completions (a 95 percent control), the assumption of no equipment
retirements through year 2032 dictates that NSPS controls are applied to the growth component only of
any PROJECTION factors. For example, if a growth factor is 1.5 for storage tanks (indicating a 50
percent increase activity), then, using Table 4-41, the 70.3 percent VOC NSPS control to this new growth
will result in a 23.4 percent control: 100 *(70.3 * (1.5 -1) / 1.5); this yields an "effective" growth rate
(combined PROJECTION and CONTROL) of 1.1485, or a 70.3 percent reduction from 1.5 to 1.0. The
impacts of all non-drilling completion VOC NSPS controls are therefore greater where growth in oil and

176


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gas production is assumed highest. Conversely, for oil and gas basins with assumed negative growth in
activity/production, VOC NSPS controls will be limited to well completions only. These reductions are
year-specific because projection factors for these sources are year-specific.

Table 4-42 shows the emission reductions for the oil and gas sectors as a result of applying the oil and gas
NSPS. Table 4-43 and Table 4-44 list the SCCs in the npoilgas and ptoilgas sectors for which the Oil
and Gas NSPS controls were. Note that controls are applied to both production and exploration-related
SCCs.)

Table 4-42. Emissions reductions for the oil and gas sectors due to applying the Oil and Gas NSPS

Sector

year

poll

2018gg

2018

pre-CoST
emissions

emissions
change from
2018

%

change

npoilgas

2032

VOC

2,425,264

2,400,100

-393,671

-16.4%

ptoilgas

2032

VOC

235,255

237,400

-9,022

-3.8%

Table 4-43. SCCs in np oilgas for which the Oil and Gas NSPS controls were applied

see

PRODUCT

OG_NSPS_SCC

TOOL
OR

STATE

Source category

SCC Description*











2310010300

OIL

3. Pneumatic
controllers: not
high or low bleed

TOOL

PRODUCTION

Crude Petroleum;Oil Well Pneumatic Devices

2310010700

OIL

5. Fugitives

TOOL

PRODUCTION

Crude Petroleum;Oil Well Fugitives

2310011020

OIL

1. Storage Tanks

TOOL

PRODUCTION

On-Shore Oil Production;Storage Tanks: Crude Oil

2310011500

OIL

5. Fugitives

TOOL

PRODUCTION

On-Shore Oil Production;Fugitives: All Processes

2310011501

OIL

5. Fugitives

TOOL

PRODUCTION

On-Shore Oil Production;Fugitives: Connectors

2310011502

OIL

5. Fugitives

TOOL

PRODUCTION

On-Shore Oil Production;Fugitives: Flanges

2310011503

OIL

5. Fugitives

TOOL

PRODUCTION

On-Shore Oil Production;Fugitives: Open Ended Lines

2310011505

OIL

5. Fugitives

TOOL

PRODUCTION

On-Shore Oil Production;Fugitives: Valves

2310011506

OIL

5. Fugitives

TOOL

PRODUCTION

On-Shore Oil Production;Fugitives: Other

2310020700

NGAS

5. Fugitives

TOOL

PRODUCTION

Natural Gas;Gas Well Fugitives

2310021010

NGAS

1. Storage Tanks

TOOL

PRODUCTION

On-Shore Gas Production;Storage Tanks: Condensate

2310021011

NGAS

1. Storage Tanks

TOOL

PRODUCTION

On-Shore Gas Production;Condensate Tank Flaring

2310021300

NGAS

3. Pneumatic
controllers: not
high or low bleed

TOOL

PRODUCTION

On-Shore Gas Production;Gas Well Pneumatic
Devices

2310021310

NGAS

6. Pneumatic
Pumps

TOOL

PRODUCTION

On-Shore Gas Production;Gas Well Pneumatic Pumps

2310021500

NGAS

2. Well
Completions

TOOL

EXPLORATION

On-Shore Gas Production;Gas Well Completion -
Flaring

2310021501

NGAS

5. Fugitives

TOOL

PRODUCTION

On-Shore Gas Production;Fugitives: Connectors

2310021502

NGAS

5. Fugitives

TOOL

PRODUCTION

On-Shore Gas Production;Fugitives: Flanges

2310021503

NGAS

5. Fugitives

TOOL

PRODUCTION

On-Shore Gas Production;Fugitives: Open Ended
Lines

2310021505

NGAS

5. Fugitives

TOOL

PRODUCTION

On-Shore Gas Production;Fugitives: Valves

2310021506

NGAS

5. Fugitives

TOOL

PRODUCTION

On-Shore Gas Production;Fugitives: Other

2310021509

NGAS

5. Fugitives

TOOL

PRODUCTION

On-Shore Gas Production;Fugitives: All Processes

177


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see

PRODUCT

OG_NSPS_SCC

TOOL
OR

STATE

Source category

SCC Description*











2310021601

NGAS

2. Well
Completions

TOOL

EXPLORATION

On-Shore Gas Production;Gas Well Venting - Initial
Completions

2310023000

CBM

6. Pneumatic
Pumps

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Dewatering Pump
Engines

2310023010

CBM

1. Storage Tanks

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Storage Tanks:
Condensate

2310023300

CBM

3. Pnuematic
controllers: not
high or low bleed

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Pneumatic Devices

2310023310

CBM

6. Pneumatic
Pumps

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Pneumatic Pumps

2310023509

CBM

5. Fugitives

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Fugitives

2310023511

CBM

5. Fugitives

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Fugitives: Connectors

2310023512

CBM

5. Fugitives

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Fugitives: Flanges

2310023513

CBM

5. Fugitives

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Fugitives: Open Ended
Lines

2310023515

CBM

5. Fugitives

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Fugitives: Valves

2310023516

CBM

5. Fugitives

TOOL

PRODUCTION

Coal Bed Methane Natural Gas;Fugitives: Other

2310023600

CBM

2. Well
Completions

TOOL

EXPLORATION

Coal Bed Methane Natural Gas;CBM Well
Completion: All Processes

2310030220

NGAS

1. Storage Tanks

TOOL

PRODUCTION

Natural Gas Liquids;Gas Well Tanks - Flashing &
Standing/Working/Breathing, Controlled

2310030300

NGAS

1. Storage Tanks

TOOL

PRODUCTION

Natural Gas Liquids;Gas Well Water Tank Losses

2310111401

OIL

6. Pneumatic
Pumps

TOOL

PRODUCTION

On-Shore Oil Exploration;Oil Well Pneumatic Pumps

2310111700

OIL

2. Well
Completions

TOOL

EXPLORATION

On-Shore Oil Exploration;Oil Well Completion: All
Processes

2310121401

NGAS

6. Pneumatic
Pumps

TOOL

PRODUCTION

On-Shore Gas Exploration;Gas Well Pneumatic Pumps

2310121700

NGAS

2. Well
Completions

TOOL

EXPLORATION

On-Shore Gas Exploration;Gas Well Completion: All
Processes

2310321010

NGAS

1. Storage Tanks

STATE

PRODUCTION

On-Shore Gas Production - Conventional;Storage
Tanks: Condensate

2310421010

NGAS

1. Storage Tanks

STATE

PRODUCTION

On-Shore Gas Production - Unconventional;Storage
Tanks: Condensate

* All SCC descriptions in this table start with "Industrial Processes;Oil and Gas Exploration and Production;"

Table 4-44. SCCs in ptoilgas for which the Oil and Gas NSPS controls were applied

SCC

Fuel

OG NSPS
SCC

NP or
PT

SCC Description*

30180010

NGAS

4. Compressor
Seals

PT

IP;Chemical Manufacturing;Equipment Leaks;Compressor Seals: Gas Stream

30600801

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Pipeline Valves and Flanges

30600802

OIL

5. Fugitives

PT

IP;Petroleum Industry ;Fugitive Emissions; Vessel Relief Valves

30600803

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Pump Seals w/o Controls

30600804

OIL

4. Compressor
Seals

PT

IP;Petroleum Industry;Fugitive Emissions;Compressor Seals

30600805

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Miscellaneous: Sampling/Non-Asphalt
Bio wing/Purging/etc.

30600806

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Pump Seals with Controls

30600811

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Pipeline Valves: Gas Streams

30600812

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Pipeline Valves: Light Liquid/Gas
Streams

178


-------
see

Fuel

OG NSPS

sec

NP or
PT

SCC Description*

30600813

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Pipeline Valves: Heavy Liquid Streams

30600815

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Open-ended Valves: All Streams

30600816

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Flanges: All Streams

30600817

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Pump Seals: Light Liquid/Gas Streams

30600818

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Pump Seals: Heavy Liquid Streams

30600819

OIL

4. Compressor
Seals

PT

IP;Petroleum Industry;Fugitive Emissions;Compressor Seals: Gas Streams

30600820

OIL

4. Compressor
Seals

PT

IP;Petroleum Industry;Fugitive Emissions;Compressor Seals: Heavy Liquid
Streams

30600822

OIL

5. Fugitives

PT

IP;Petroleum Industry ;Fugitive Emissions; Vessel Relief Valves: All Streams

30688801

OIL

5. Fugitives

PT

IP;Petroleum Industry;Fugitive Emissions;Specify in Comments Field

31000101

OIL

2. Well
Completions

PT

IP;Oil and Gas Production;Crude Oil Production;Well Completion

31000130

OIL

4. Compressor
Seals

PT

IP;Oil and Gas Production;Crude Oil Production;Fugitives: Compressor Seals

31000151

OIL

3. Pnuematic
controllers: high
or low bleed

PT

IP;Oil and Gas Production;Crude Oil Production;Pneumatic Controllers, Low
Bleed

31000152

OIL

3. Pnuematic
controllers: high
or low bleed

PT

IP;Oil and Gas Production;Crude Oil Production;Pneumatic Controllers High Bleed
>6 scfh

31000153

OIL

3. Pnuematic
controllers: not
high or low
bleed

PT

IP;Oil and Gas Production;Crude Oil Production;Pneumatic Controllers
Intermittent Bleed

31000207

NGAS

5. Fugitives

PT

IP;Oil and Gas Production;Natural Gas Production; Valves: Fugitive Emissions

31000220

NGAS

5. Fugitives

NP AN
D PT

IP;Oil and Gas Production;Natural Gas Production;All Equipt Leak Fugitives
(Valves, Flanges, Connections, Seals, Drains

31000225

NGAS

4. Compressor
Seals

PT

IP;Oil and Gas Production;Natural Gas Production;Compressor Seals

31000231

NGAS

5. Fugitives

PT

IP;Oil and Gas Production;Natural Gas Production;Fugitives: Drains

31000233

NGAS

3. Pnuematic
controllers: high
or low bleed

PT

IP;Oil and Gas Production;Natural Gas Production;Pneumatic Controllers, Low
Bleed

31000235

NGAS

3. Pnuematic
controllers: not
high or low
bleed

PT

IP;Oil and Gas Production;Natural Gas Production;Pneumatic Controllers
Intermittent Bleed

31000309

NGAS

4. Compressor
Seals

PT

IP;Oil and Gas Production;Natural Gas Processing;Compressor Seals

31000324

NGAS

3. Pnuematic
controllers: high
or low bleed

NP AN
D_PT

IP;Oil and Gas Production;Natural Gas Processing;Pneumatic Controllers Low
Bleed

31000325

NGAS

3. Pnuematic
controllers: high
or low bleed

NP AN
D_PT

IP;Oil and Gas Production;Natural Gas Processing;Pneumatic Controllers, High
Bleed >6 scfh

31000326

NGAS

3. Pnuematic
controllers: not
high or low
bleed

PT

IP;Oil and Gas Production;Natural Gas Processing;Pneumatic Controllers
Intermittent Bleed

31000506

OIL

1. Storage Tanks

PT

IP;Oil and Gas Production;Liquid Waste Treatment;Oil-Water Separation
Wastewater Holding Tanks

31088801

BOTH

5. Fugitives

PT

IP;Oil and Gas Production;Fugitive Emissions;Specify in Comments Field

31088811

BOTH

5. Fugitives

NP AN
D PT

IP;Oil and Gas Production;Fugitive Emissions;Fugitive Emissions

179


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see

Fuel

OG NSPS

sec

NP or
PT

SCC Description*

31700101

NGAS

3. Pnuematic
controllers: high
or low bleed

PT

IP;NGTS;Natural Gas Transmission and Storage Facilities;Pneumatic Controllers
Low Bleed

39090001

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Residual Oil: Breathing
Loss

39090002

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Residual Oil: Working
Loss

39090003

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Distillate Oil (No. 2):
Breathing Loss

39090004

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Distillate Oil (No. 2):
Working Loss

39090005

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Oil No. 6: Breathing Loss

39090006

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Oil No. 6: Working Loss

39090007

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Methanol: Breathing Loss

39090008

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Methanol: Working Loss

39090009

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Residual Oil/Crude Oil:
Breathing Loss

39090010

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Residual Oil/Crude Oil:
Working Loss

39090012

OIL

1. Storage Tanks

PT

IP;In-process Fuel Use;Fuel Storage - Fixed Roof Tanks;Dual Fuel (Gas/Oil):
Working Loss

40301001

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Gasoline RVP 13: Breathing Loss (67000 Bbl. Tank Size)

40301002

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Gasoline RVP 10: Breathing Loss (67000 Bbl. Tank Size)

40301003

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Gasoline RVP 7: Breathing Loss (67000 Bbl. Tank Size)

40301004

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Gasoline RVP 13: Breathing Loss (250000 Bbl. Tank Size)

40301005

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Gasoline RVP 10: Breathing Loss (250000 Bbl. Tank Size)

40301007

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Gasoline RVP 13: Working Loss (Tank Diameter Independent)

40301008

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Gasoline RVP 10: Working Loss (Tank Diameter Independent)

40301009

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Gasoline RVP 7: Working Loss (Tank Diameter Independent)

40301010

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refmeries;Fixed Roof Tanks (Varying
Sizes);Crude Oil RVP 5: Breathing Loss (67000 Bbl. Tank Size)

40301011

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Crude Oil RVP 5: Breathing Loss (250000 Bbl. Tank Size)

40301012

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Crude Oil RVP 5: Working Loss (Tank Diameter Independent)

40301013

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying Sizes);Jet
Naphtha (JP-4): Breathing Loss (67000 Bbl. Tank Size)

40301015

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying Sizes);Jet
Naphtha (JP-4): Working Loss (Tank Diameter Independent)

40301019

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refmeries;Fixed Roof Tanks (Varying
Sizes);Distillate Fuel #2: Breathing Loss (67000 Bbl. Tank Size)

40301021

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Distillate Fuel #2: Working Loss (Tank Diameter Independent)

40301065

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Grade 6 Fuel Oil: Breathing Loss (250000 Bbl. Tank Size)

40301075

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Grade 6 Fuel Oil: Working Loss (Independent Tank Diameter)

40301079

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Grade 1 Fuel Oil: Working Loss (Independent Tank Diameter)

40301097

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Other Liquids: Breathing Loss (67000 Bbl. Tank Size)

180


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see

Fuel

OG NSPS
SCC

NP or
PT

SCC Description*

40301098

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Other Liquids: Breathing Loss (250000 Bbl. Tank Size)

40301099

OIL

1. Storage Tanks

PT

CE;Petroleum Product Storage at Refineries;Fixed Roof Tanks (Varying
Sizes);Other Liquids: Working Loss (Tank Diameter Independent)

40388801

OIL

5. Fugitives

PT

CE;Petroleum Product Storage at Refineries;Fugitive Emissions;General

40400300

OIL

1. Storage Tanks

PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank: Flashing Loss

40400301

OIL

1. Storage Tanks

PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank: Breathing Loss

40400302

OIL

1. Storage Tanks

PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank: Working Loss

40400311

OIL

1. Storage Tanks

NP AN
D PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank, Condensate, working+breathing+flashing losses

40400312

OIL

1. Storage Tanks

NP AN
D PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank, Crude Oil, working+breathing+flashing losses

40400313

OIL

1. Storage Tanks

PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank, Lube Oil, working+breathing+flashing losses

40400314

OIL

1. Storage Tanks

PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank, Specialty Chem-working+breathing+flashing

40400315

OIL

1. Storage Tanks

PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank, Produced Water, working+breathing+flashing

40400316

OIL

1. Storage Tanks

PT

CE;Petroleum Liquids Storage (non-Refinery );Oil and Gas Field Storage and
Working Tanks;Fixed Roof Tank, Diesel, working+breathing+flashing losses

40701613

OIL

1. Storage Tanks

PT

CE;Organic Chemical Storage;Fixed Roof Tanks - Alkanes (Paraffins);Petroleum
Distillate: Breathing Loss

40701614

OIL

1. Storage Tanks

PT

CE;Organic Chemical Storage;Fixed Roof Tanks - Alkanes (Paraffins);Petroleum
Distillate: Working Loss

* For all entries in this table, TOOL OR STATE = STATE and SRC CAT = PRODUCTION; In the SCC
description, IP is an abbreviation for Industrial Processes and CE is an abbreviation for Chemical Evaporation

4.2.4.2 RICE NSPS (nonpt, ptnonipm, np_oilgas, pt_oilgas)

Packets:

Control_2016_2026_RICE_NSPS_nonpt_v2_platform_l 6jul202 l_vO
Control_2026_2032_RICE_NSPS_nonpt_ptnonipm_v2_platform_13aug2021_v0
Control_2018_2032_RICE_NSPS_np_oilgas_for_2032gg_21 sep2022_v0
Control_2018_2032_RICE_NSPS_pt_oilgas_for_2032gg_22sep2022_v0

Multiple sectors are affected by the RICE NSPS controls. The packet names include the sectors to which
the specific packet applies. For the ptnonipm sector, 2026 emissions from 2016v3 platform were used as
the baseline for projections, so RICE NSPS controls only need to be applied beyond 2026 for that sector.
The 2026-to-2032 control packets were reused from 2016v2 platform.

For the pt_oilgas and np_oilgas sectors, year-specific RICE NSPS factors were generated for 2032. New
growth factors based on AEO2022 and state-specific production data were calculated for the oil and gas
sectors which were included in the calculation of the new RICE NSPS control factors, although the actual
control efficiency calculation methodology did not change from 2018gf to 2018v2. For RICE NSPS
controls, the EPA emission requirements for stationary engines differ according to whether the engine is
new or existing, whether the engine is located at an area source or major source, and whether the engine is
a compression ignition or a spark ignition engine. Spark ignition engines are further subdivided by power
cycle, two-stroke versus four-stroke, and whether the engine is rich burn or lean burn. The NSPS

181


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reduction was applied for lean burn, rich burn and "combined" engines using Equation 4-2 and
information listed in Table 4-41.

Table 4-45, Table 4-46, Table 4-47 and Table 4-48 show the reductions in emissions in the nonpt,
ptnonipm, and npoilgas and ptoilgas sectors after the application of the RICE NSPS CONTROL
packet. Note that for nonpoint oil and gas, VOC reductions were only appropriate in the state of
Pennsylvania. Table 4-49, Table 4-50, and Table 4-51 show the SCCs to which the NSPS controls are
applied in the nonpt, ptnonipm, np oilgas, and pt oilgas sectors.

Table 4-45. Emissions reductions in nonpt due to RICE NSPS

year

Poll

2018v2 (tons)

Emissions reductions
(tons)

% change

2032

CO

1,945,327

-32,620

-1.7%

2032

NOX

750,001

-52,059

-6.9%

Table 4-46. Emissions reductions in ptnonipm due to the RICE NSPS

year

poll

2026gf (tons)

Emissions
reductions (tons)

% change

2032

CO

1,380,825

-155

-0.01%

2032

NOX

860,031

-285

-0.03%

2032

VOC

760,436

-1.8

0.00%

Table 4-47. Emissions reductions in np oilgas due to the RICE NSPS

Year

Poll

2018v2 (tons)

2018 pre-CoST
emissions

Emissions
reduction

% change

2032

CO

664,681

661,330

-79,455

-12.0%

2032

NOX

670,576

648,890

-113,029

-17.4%

2032

VOC

2,425,264

2,400,113

-534

0.0%

Table 4-48. Emissions reductions in pt oilgas du to the RICE NSPS

Year

Pollutant

2018

Emissions Reductions

% change

2032

CO

208,810

-18,564

-8.9%

2032

NOX

424,313

-50,961

-12.0%

2032

VOC

235,255

-312

-0.1%

Table 4-49. SCCs and Engine Types where RICE NSPS controls applied for nonpt and ptnonipm

see

Lean, Rich,
or Combined

SCCDESC

20200202

Combined

Internal Combustion Engines; Industrial; Natural Gas; Reciprocating

20200253

Rich

Internal Combustion Engines; Industrial; Natural Gas; 4-cycle Rich Burn

20200254

Lean

Internal Combustion Engines; Industrial; Natural Gas; 4-cycle Lean Burn

20200256

Lean

Internal Combustion Engines; Industrial; Natural Gas; 4-cycle Clean Burn

182


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see

Lean, Rich,
or Combined

SCCDESC

20300201

Combined

Internal Combustion Engines; Commercial/Institutional; Natural Gas;
Reciprocating

2102006000

Combined

Stationary Source Fuel Combustion; Industrial; Natural Gas; Total: Boilers
and IC Engines

2102006002

Combined

Stationary Source Fuel Combustion; Industrial; Natural Gas; All IC Engine
Types

2103006000

Combined

Stationary Source Fuel Combustion; Commercial/Institutional; Natural Gas;
Total: Boilers and IC Engines

Table 4-50. Non-point Oil and Gas SCCs where RICE NSPS controls are applied

see

Lean/ Rich/
Combined

Product

Source
Category

SCCDescription

2310000220

Combined

BOTH

EXPLORATION

Industrial Processes;Oil and Gas Exploration and
Production;All Processes;Drill Rigs;;

2310000660

Combined

BOTH

EXPLORATION

Industrial Processes;Oil and Gas Exploration and
Production;All Processes;Hydraulic Fracturing Engines;;

2310020600

Combined

NGAS

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;Natural Gas;Compressor Engines;;

2310021202

Lean

NGAS

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;On-Shore Gas Production;Natural Gas Fired
4Cycle Lean Burn Compressor Engines 50 To 499 HP;;

2310021251

Lean

NGAS

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;On-Shore Gas Production;Lateral Compressors 4
Cycle Lean Burn;;

2310021302

Rich

NGAS

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;On-Shore Gas Production;Natural Gas Fired
4Cycle Rich Bum Compressor Engines 50 To 499 HP;;

2310021351

Rich

NGAS

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;On-Shore Gas Production;Lateral Compressors 4
Cycle Rich Burn;;

2310023202

Lean

CBM

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;Coal Bed Methane Natural Gas;CBM Fired 4Cycle
Lean Burn Compressor Engines 50 To 499 HP;;

2310023251

Lean

CBM

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;Coal Bed Methane Natural Gas;Lateral
Compressors 4 Cycle Lean Burn;;

2310023302

Rich

CBM

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;Coal Bed Methane Natural Gas;CBM Fired 4Cycle
Rich Burn Compressor Engines 50 To 499 HP;;

2310023351

Rich

CBM

PRODUCTION

Industrial Processes;Oil and Gas Exploration and
Production;Coal Bed Methane Natural Gas;Lateral
Compressors 4 Cycle Rich Burn;;

2310300220

Combined

NGAS

EXPLORATION

Industrial Processes;Oil and Gas Exploration and
Production;All Processes - Conventional;Drill Rigs;;

2310400220

Combined

BOTH

EXPLORATION

Industrial Processes;Oil and Gas Exploration and
Production;All Processes - Unconventional;Drill Rigs;;

183


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Table 4-51. Point source SCCs in ptoilgas sector where RICE NSPS controls applied

see

Lean, Rich, or
Combined

SCCDESC

20200202

Combined

Internal Combustion Engines; Industrial; Natural Gas; Reciprocating

20200253

Rich

Internal Combustion Engines; Industrial; Natural Gas;4-cycle Rich Burn

20200254

Lean

Internal Combustion Engines; Industrial; Natural Gas;4-cycle Lean Burn

20200256

Combined

Internal Combustion Engines; Industrial; Natural Gas;4-cycle Clean Burn

20300201

Combined

Internal Combustion Engines; Commercial/Institutional; Natural Gas;
Reciprocating

31000203

Combined

Industrial Processes; Oil and Gas Production; Natural Gas Production;
Compressors (See also 310003-12 and -13)

4.2.4.3 Fuel Sulfur Rules (nonpt)

Packets:

Control_2016_202X_MANEVU_Sulfur_fromMARAMA_v l_platform_22aug2022_nf_v 1

The control packet for fuel sulfur rules is the same for all analytic years. Fuel sulfur rules controls are
reflected for the following states: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey,
Rhode Island, and Vermont. The fuel limits for these states are incremental starting after year 2012, but
are fully implemented by July 1, 2018, in these states. The control packet representing these controls was
updated by MARAMA for the 2016vl platform. For 2018v2, states that had fully implemented their
controls by 2017 were removed from the control packet (namely Delaware, New York, and Pennsylvania)
because 2017 NEI was used for nonpoint emissions.

Summaries of the sulfur rules by state, with emissions reductions relative to the entire sector emissions
and relative to the analytic year emissions for the affected SCCs are provided in Table 4-52, which
reflects the impacts of the MARAMA packet only, as these reductions are not estimated in non-
MARAMA states. A negligible amount of reductions occur in the pt oilgas sector. Note that ptnonipm
sources are not impacted in 2016v3 platform since the starting point for the analytic year emissions was
the 2019 NEI.

Table 4-52. Summary of fuel sulfur rule impacts on nonpoint S02 emissions for 2032

Pollutant

State

2032 pre-control
Emissions (tons)

2032 post-
control

Emissions (tons)

Change in

emissions

(tons)

Percent
change

NOX

Connecticut

3,356

3,112

-244

-7.3%

NOX

Maine

5,641

5,321

-320

-5.7%

NOX

Massachusetts

8,825

8,354

-472

-5.3%

NOX

New Hampshire

5,996

5,761

-235

-3.9%

NOX

Rhode Island

799

740

-59

-7.4%

NOX

Vermont

802

729

-73

-9.1%

NOX

Six state total

25,419

24,017

-1,402

-5.5%

S02

Connecticut

1,313

79

-1,234

-94.0%

S02

Maine

1,112

35

-1,078

-96.9%

184


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Pollutant

State

2032 pre-control
Emissions (tons)

2032 post-
control

Emissions (tons)

Change in

emissions

(tons)

Percent
change

S02

Massachusetts

2,090

83

-2,008

-96.0%

S02

New Hampshire

3,797

19

-3,778

-99.5%

S02

Rhode Island

336

38

-298

-88.7%

S02

Vermont

368

25

-344

-93.3%

S02

Six state total

9,017

279

-8,739

-96.9%

S02

ALL state total

167,825

159,086

-8,739

-5.2%

4.2.4.4 Natural Gas Turbines N0X NSPS (ptnonipm, pt_oilgas)

Packets:

Control_2018_2032_NG_Turbines_NSPS_pt_oilgas_for_2032gg_22sep2022_v0

Control_2026_2032_NG_Turbines_NSPS_ptnonipm_v2_platform_13aug2021_v0

For ptnonipm, the packet for 2032 was reused from the 2016v2 platform. For pt oilgas, the packet for
2018v2 is based on updated growth information for that sector from state-historical production data and
the AEO2022 production forecast database. The new growth factors were to calculate the new control
efficiencies for all analytic year (2032). The control efficiency calculation methodology did not change
from the 2016v3 modeling platform to the 2018v2 platform.

Natural Gas Turbines NSPS controls were generated based on examination of emission limits for
stationary combustion turbines that are not in the power sector. In 2006, the EPA promulgated standards
of performance for new stationary combustion turbines in 40 CFR part 60, subpart KKKK. The standards
reflect changes in NOx emission control technologies and turbine design since standards for these units
were originally promulgated in 40 CFR part 60, subpart GG. The 2006 NSPSs affecting NOx and SO2
were established at levels that bring the emission limits up-to-date with the performance of current
combustion turbines. Stationary combustion turbines were also regulated by the NOx State
Implementation Plan (SIP) Call, which required affected gas turbines to reduce their NOx emissions by
60 percent. Table 4-53 compares the 2006 NSPS emission limits with the NOx Reasonably Available
Control Technology (RACT) regulations in selected states within the NOx SIP Call region. More
information on the NOx SIP call is available at: https://www.epa.gov/csapr/final-update-nox-sip-call-
regulations-emissions-monitoring-provisions-state-implementation. The state NOx RACT regulations
summary (Pechan, 2001) is from a year 2001 analysis, so some states may have updated their rules since
that time.

Table 4-53. Stationary gas turbines NSPS analysis and resulting emission rates used to compute

controls

NOx Emission Limits for New Stationary Combustion Turbines

Firing Natural Gas

<50
MMBTU/hr

50-850
MMBTU/hr

>850
MMBTU/hr



Federal NSPS

100

25

15

ppm











State RACT Regulations

5-100
MMBTU/hr

100-250
MMBTU/hr

>250
MMBTU/hr



185


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NOx Emission Limits for New Stationary Combustion Turbines

Connecticut

225

75

75

ppm

Delaware

42

42

42

ppm

Massachusetts

65*

65

65

ppm

New Jersey

50*

50

50

ppm

New York

50

50

50

ppm

New Hampshire

55

55

55

ppm

* Only applies to 25-100 MMBTU/hr

Notes: The above state RACT table is from a 2001 analysis. The current NY State regulations have the

same emission limits.









New source emission rate (Fn)

NOx ratio (Fn)

Control (%)

NOx SIP Call states plus CA

= 25 / 42 =

0.595

40.5%

Other states

= 25 / 105 =

0.238

76.2%

For control factor development, the existing source emission ratio was set to 1.0 for combustion turbines.
The new source emission ratio for the NOx SIP Call states and California is the ratio of state NOx
emission limit to the Federal NSPS. A complicating factor in the above is the lack of size information in
the stationary source SCCs. Plus, the size classifications in the NSPS do not match the size differentiation
used in state air emission regulations. We accepted a simplifying assumption that most industrial
applications of combustion turbines are in the 100-250 MMBtu/hr size range and computed the new
source emission rates as the NSPS emission limit for 50-850 MMBtu/hr units divided by the state
emission limits. We used a conservative new source emission ratio by using the lowest state emission
limit of 42 ppmv (Delaware). This yields a new source emission ratio of 25/42, or 0.595 (40.5 percent
reduction) for states with existing combustion turbine emission limits. States without existing turbine
NOx limits would have a lower new source emission ratio: the uncontrolled emission rate (105 ppmv via
AP-42) divided into 25 ppmv = 0.238 (76.2 percent reduction). This control was then plugged into
Equation 4-2 as a function of the year-specific projection factor. Also, Natural Gas Turbines control
factors supplied by MARAMA were used within the MARAMA region for 2032. The Natural Gas
Turbines control packet for pt oilgas also includes additional controls for the EPNG Williams facility in
Arizona, in order to reduce the post-control facility total of 584.77 tons/yr NOx.

Table 4-54 shows the reduction in NOx emissions after the application of the Natural Gas Turbines NSPS
CONTROL packet and include emissions both inside and outside the MARAMA region. Table 4-55 and
Table 4-56 list the point source SCCs for which Natural Gas Turbines NSPS controls were applied.

Table 4-54. Emissions reductions due to the Natural Gas Turbines NSPS

Sector

Year

Pollutant

2026gf (tons)

Emissions
reduction (tons)

0/

/O

change

ptnonipm

2032

NOX

860,031

-726

-0.08%

pt oilgas

2032

NOX

424,313

-13,984

-3.3%

Table 4-55. SCCs in ptnonipm for which Natural Gas Turbines NSPS controls were applied

see

SCC Description

20200201

Internal Combustion Engines; Industrial; Natural Gas; Turbine

20200203

Internal Combustion Engines; Industrial; Natural Gas; Turbine: Cogeneration

186


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see

SCC Description

20200209

Internal Combustion Engines; Industrial; Natural Gas; Turbine: Exhaust

20200701

Internal Combustion Engines; Industrial; Process Gas; Turbine

20200714

Internal Combustion Engines; Industrial; Process Gas; Turbine: Exhaust

20300203

Internal Combustion Engines; Commercial/Institutional; Natural Gas; Turbine:
Cogeneration

Table 4-56. SCCs in ptoilgas for which Natural Gas Turbines NSPS controls were applied

SCC

SCC description

20200201

Internal Combustion Engines; Industrial; Natural Gas; Turbine

20200209

Internal Combustion Engines; Industrial; Natural Gas; Turbine: Exhaust

20300202

Internal Combustion Engines; Commercial/Institutional; Natural Gas; Turbine

20300209

Internal Combustion Engines; Commercial/Institutional; Natural Gas; Turbine: Exhaust

20200203

Internal Combustion Engines; Industrial; Natural Gas; Turbine: Cogeneration

20200714

Internal Combustion Engines; Industrial; Process Gas; Turbine: Exhaust

20300203

Internal Combustion Engines; Commercial/Institutional; Natural Gas; Turbine:
Cogeneration

4.2.4.5 Process Heaters NOx NSPS (ptnonipm, pt_oilgas)

Packets:

Control_2018_2032_Process_Heaters_NSPS_pt_oilgas_for_2032gg_22sep2022_v0
Control_2026_2032_Process_Heaters_NSPS_ptnonipm_v2_platform_13aug2021_v0

For ptnonipm, the packet for 2026 to 2032 was reused from the 2016v2 platform. For pt oilgas, the
packets were newly developed for 2018v2 based on updated information.

Process heaters are used throughout refineries and chemical plants to raise the temperature of feed
materials to meet reaction or distillation requirements. Fuels are typically residual oil, distillate oil,
refinery gas, or natural gas. In some sense, process heaters can be considered as emission control devices
because they can be used to control process streams by recovering the fuel value while destroying the
VOC. The criteria pollutants of most concern for process heaters are NOx and SO2. In 2018, it is assumed
that process heaters have not been subject to regional control programs like the NOx SIP Call, so most of
the emission controls put in-place at refineries and chemical plants have resulted from RACT regulations
that were implemented as part of SIPs to achieve ozone NAAQS in specific areas, and refinery consent
decrees. The boiler/process heater NSPS established NOx emission limits for new and modified process
heaters. These emission limits are displayed in Table 4-57.

Table 4-57. Process Heaters NSPS analysis and 2018v2 new emission rates used to estimate controls

NOx emission rate Existing PPMV (=Fe)

Natural Draft
(fraction)

Forced Draft
(fraction)

Average

80

0.4

0



100

0.4

0.5



150

0.15

0.35



200

0.05

0.1



240

0

0.05



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Cumulative, weighted (=Fe)

104.5

134.5

119.5

NSPS Standard

40

60



New Source NOx ratio (=Fn)

0.383

0.446

0.414

NSPS Control (%)

61.7

55.4

58.6

For computations, the existing source emission ratio (Fe) was set to 1.0. The computed (average) NOx
emission factor ratio for new sources (Fn) is 0.41 (58.6 percent control). The retirement rate is the inverse
of the expected unit lifetime. There is limited information in the literature about process heater lifetimes.
This information was reviewed at the time that the Western Regional Air Partnership (WRAP) developed
its initial regional haze program emission projections, and energy technology models used a 20-year
lifetime for most refinery equipment. However, it was noted that in practice, heaters would probably have
a lifetime that was on the order of 50 percent above that estimate. Therefore, a 30-year lifetime was used
to estimate the effects of process heater growth and retirement. This yields a 3.3 percent retirement rate.
This control was then plugged into Equation 4-2 as a function of the year-specific projection factor.

The impact on emissions from applying the process heaters NSPS is shown in Table 4-58. Table 4-59 and
Table 4-60 list the point source SCCs for which the Process Heaters NSPS controls were applied.

Table 4-58. Emissions reductions due to the application of the Process Heaters NSPS

Sector

Year

Pollutant

2026gf
(tons)

Emissions
reduction (tons)

0/

/o

change

ptnonipm

2032

NOX

860,031

-5,923

-0.7%

pt oilgas

2032

NOX

424,313

-2,224

-0.5%

Table 4-59. SCCs in ptnonipm for which Process Heaters NSPS controls were applied

see

SCC Description*

30190003

IP; Chemical Manufacturing; Fuel Fired Equipment; Process Heater: Natural Gas

30190004

IP; Chemical Manufacturing; Fuel Fired Equipment; Process Heater: Process Gas

30590002

IP; Mineral Products; Fuel Fired Equipment; Residual Oil: Process Heaters

30590003

IP; Mineral Products; Fuel Fired Equipment; Natural Gas: Process Heaters

30600101

IP; Petroleum Industry; Process Heaters; Oil-fired

30600102

IP; Petroleum Industry; Process Heaters; Gas-fired

30600103

IP; Petroleum Industry; Process Heaters; Oil

30600104

IP; Petroleum Industry; Process Heaters; Gas-fired

30600105

IP; Petroleum Industry; Process Heaters; Natural Gas-fired

30600106

IP; Petroleum Industry; Process Heaters; Process Gas-fired

30600107

IP; Petroleum Industry; Process Heaters; Liquified Petroleum Gas (LPG)

30600199

IP; Petroleum Industry; Process Heaters; Other Not Classified

30990003

IP; Fabricated Metal Products; Fuel Fired Equipment; Natural Gas: Process Heaters

31000401

IP; Oil and Gas Production; Process Heaters; Distillate Oil (No. 2)

31000402

IP; Oil and Gas Production; Process Heaters; Residual Oil

31000403

IP; Oil and Gas Production; Process Heaters; Crude Oil

31000404

IP; Oil and Gas Production; Process Heaters; Natural Gas

31000405

IP; Oil and Gas Production; Process Heaters; Process Gas

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see

SCC Description*

31000406

IP; Oil and Gas Production; Process Heaters; Propane/Butane

31000413

IP; Oil and Gas Production; Process Heaters; Crude Oil: Steam Generators

31000414

IP; Oil and Gas Production; Process Heaters; Natural Gas: Steam Generators

31000415

IP; Oil and Gas Production; Process Heaters; Process Gas: Steam Generators

39900501

IP; Miscellaneous Manufacturing Industries; Process Heater/Furnace; Distillate Oil

39900601

IP; Miscellaneous Manufacturing Industries; Process Heater/Furnace; Natural Gas

39990003

IP; Miscellaneous Manufacturing Industries; Miscellaneous Manufacturing Industries;
Natural Gas: Process Heaters

* IP = Industrial Processes

Table 4-60. SCCs in ptoilgas for which Process Heaters NSPS controls were applied

SCC

SCC Description

30190003

Industrial Processes; Chemical Manufacturing; Fuel Fired Equipment; Process Heater: Natural Gas

30600102

Industrial Processes; Petroleum Industry; Process Heaters; Gas-fired

30600104

Industrial Processes; Petroleum Industry; Process Heaters; Gas-fired

30600105

Industrial Processes; Petroleum Industry; Process Heaters; Natural Gas-fired

30600106

Industrial Processes; Petroleum Industry; Process Heaters; Process Gas-fired

30600199

Industrial Processes; Petroleum Industry; Process Heaters; Other Not Classified

30990003

Industrial Processes; Fabricated Metal Products; Fuel Fired Equipment; Natural Gas: Process Heaters

31000401

Industrial Processes; Oil and Gas Production; Process Heaters; Distillate Oil (No. 2)

31000402

Industrial Processes; Oil and Gas Production; Process Heaters; Residual Oil

31000403

Industrial Processes; Oil and Gas Production; Process Heaters; Crude Oil

31000404

Industrial Processes; Oil and Gas Production; Process Heaters; Natural Gas

31000405

Industrial Processes; Oil and Gas Production; Process Heaters; Process Gas

31000413

Industrial Processes; Oil and Gas Production; Process Heaters; Crude Oil: Steam Generators

31000414

Industrial Processes; Oil and Gas Production; Process Heaters; Natural Gas: Steam Generators

31000415

Industrial Processes; Oil and Gas Production; Process Heaters; Process Gas: Steam Generators

39900501

Industrial Processes; Miscellaneous Manufacturing Industries; Process Heater/Furnace; Distillate Oil

39900601

Industrial Processes; Miscellaneous Manufacturing Industries; Process Heater/Furnace; Natural Gas

4.2.4.6 Ozone Transport Commission Rules (np_solvents)

Packets:

Control_2016_202X_solvents_OTC_v3_platform_MARAMA_l 4sep2022_nf_v 1

Several MARAMA states have adopted rules reflecting the recommendations of the Ozone Transport
Commission (OTC) for reducing VOC emissions from consumer products, architectural and industrial
maintenance coatings, and various other solvents. The rules affected 27 different SCCs in the surface
coatings (2401xxxxxx), degreasing (2415000000), graphic arts (2425010000), miscellaneous industrial
(2440020000), and miscellaneous non-industrial consumer and commercial (246xxxxxxx) categories. The
packet applies only to MARAMA states and not all states adopted all rules. This packet applies to
emissions in the np solvents sector. The new SCCs in the solvents sector were added to the packet.

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The OTC also developed a model rule to address VOC emissions from portable fuel containers (PFCs) via
performance standards and phased-in PFC replacement that was implemented in two phases. Some states
adopted one or both phases of the OTC rule, while others relied on the Federal rule. MARAMA
calculated control factors to reflect each state's compliance dates and, where states implemented one or
both phases of the OTC requirements prior to the Federal mandate, accounted for the early reductions in
the control factors. The rules affected permeation, evaporation, spillage, and vapor displacement for
residential (250101 lxxx) and commercial (2501012xxx) portable gas can SCCs. This packet applies to
the nonpt sector.

MARAMA provided control packets to apply the solvent and PFC rule controls. The 2018v2 OTC packet
is based on the packet from the 2016v3 platform, except with controls enacted prior to 2018 (and
therefore already reflected in the base year inventory) removed from the packet.

4.2.4.7 Good Neighbor Plan 2015 Ozone NAAQS (ptnonipm, pt_oilgas)

The Good Neighbor Plan for the 2015 ozone NAAQS includes NOx controls for both EGU and non-EGU
sources. The regulation ensures that 23 states meet the Clean Air Act's "Good Neighbor" requirements by
reducing pollution that significantly contributes to problems attaining and maintaining EPA's health-
based air quality standard for ground-level ozone (or "smog"), known as the 2015 Ozone National
Ambient Air Quality Standards (NAAQS), in downwind states. The estimated impact of the rule on the
non-EGUs modeled in this study is reflect in Table 4-61.

Table 4-61. NOx emissions reductions after application of Good Neighbor Plan control packet

Year

Sector

Pollutant

Uncontrolled
Emissions

Emissions Reductio
(tons/yr)n

%

change

2032

ptnonipm

NOX

90,630

-36,417

-40.2%

2032

pt oilgas

NOX

51,408

-10,315

-20.1%

4.3 Sectors with Projections Computed Outside of CoST

Projections for sectors not calculated using CoST are discussed in this section.

4.3.1 Nonroad Mobile Equipment Sources (nonroad)

Outside of California and Texas, the MOVES3 model (version 3.0.3) was run for 2032. The fuels used are
specific to the analytic year, but the meteorological data represented the year 2018. The 2032 nonroad
emissions include all nonroad control programs finalized as of the date of the MOVES3.0.3 release,
including most recently:

•	Emissions Standards for New Nonroad Spark-Ignition Engines, Equipment, and Vessels: October
2008 (https://www.epa.gov/regulations-emissions-vehicles-and-engines/final-rule-control-
emissions-nonroad-spark-ignition);

•	Growth and control from Locomotives and Marine Compression-Ignition Engines Less than 30
Liters per Cylinder: March 2008 (https://www.epa.gov/regulations-emissions-vehicles-and-
engines/final-rule-control-emissions-air-pollution-locomotive); and

•	Clean Air Nonroad Diesel Final Rule - Tier 4: May 2004 (https://www.epa.gov/regulations-
emissions-vehicles-and-engines/final-rule-control-emissions-air-pollution-nonroad-dieseP.

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The resulting analytic year inventories were processed into the format needed by SMOKE in the same
way as the base year emissions.

Inside California and Texas, CARB and TCEQ provided separate datasets for various analytic years. For
2018v2, CARB provided new nonroad inventories for 2032. In Texas, a 2026 nonroad inventory was
interpolated from TCEQ-provided 2023 and 2028 inventories, and then the interpolated 2026 emissions
were projected to 2032 using 2026-to-2032 trends calculated from MOVES3 emissions in Texas. VOC
and PM2.5 by speciation profile, and VOC HAPs, were added to all analytic year California and Texas
nonroad inventories using the same procedure as for the 2018 inventory, but based on the analytic year
MOVES runs instead of the 2018 MOVES run.

4.3.2 Onroad Mobile Sources (onroad)

For 2018v2, MOVES3 was run for 2032 to obtain onroad emission factors that account for the impact of
on-the-books rules that are implemented into MOVES3. These include regulations such as:

•	Safer Affordable Fuel Efficient (SAFE) Vehicles Final Rule for Model Years 2021-2026 (March
2020);

•	Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy -
Duty Engines and Vehicles - Phase 2 (October 2016);

•	Tier 3 Vehicle Emission and Fuel Standards Program (March 2014)
(https://www.epa.gov/regulations-emissions-vehicles-and-engines/final-rule-control-air-pollution-
motor-vehicles-tier-3);

•	2017 and Later Model Year Light-Duty Vehicle GHG Emissions and Corporate Average Fuel
Economy Standards (October 2012);

•	Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy -
Duty Engines and Vehicles (September 2011);

•	Regulation of Fuels and Fuel Additives: Modifications to Renewable Fuel Standard Program
(RFS2) (December 2010); and

•	Light-Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy
Standards Final Rule for Model-Year 2012-2016 (May 2010).

Local inspection and maintenance (I/M) and other onroad mobile programs are included such as:
California LEVIII, the National Low Emissions Vehicle (LEV) and Ozone Transport Commission (OTC);
LEV regulations, local fuel programs, and Stage II refueling control programs. Note that MOVES3
emission rates for model years 2017 and beyond are equivalent to CA LEVIII rates for NOx and VOC.
Therefore, it was not necessary to update the rates used for states that have adopted the rules in 2020 or
later years.

An update in 2018v2 was to apply adjustment factors to reflect the impacts of the light duty greenhouse
gas rule finalized in the Revised 2023 and Later Model Year Light-Duty Vehicle Greenhouse Gas
Emissions Standards, 86 FR 74434 (December 30, 2021).27 The adjustment factors that reflect the impacts
of the rule on CAPs are shown in Table 4-62. These adjustment factors are intended to represent not only

27 https ://www. govinfo. gov/content/pkg/FR-2021-12-30/pdf/2021-27854.pdf.

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the effects of the rule on onroad emissions in 2032, but also ancillary effects on stationary emissions such
as increased electricity production for electric vehicles.

Table 4-62. Light duty greenhouse gas rule adjustments for 2032 onroad emissions

Year

Source Type

Fuel Type

CO

voc

NOx

S02

PM

2032

Light Truck

Diesel

-13.36%

-35.97%

-27.45%

-31.63%

-50.52%

2032

Light Truck

E85

+0.74%

-0.56%

+1.79%

+119.02%

+3.97%

2032

Light Truck

Gasoline

-0.67%

-10.50%

+1.59%

+169.88%

+0.06%

2032

Passenger Car

Diesel

+2.02%

+2.70%

+6.44%

+351.16%

+6.92%

2032

Passenger Car

E85

+1.89%

+3.21%

+7.61%

+540.54%

+12.99%

2032

Passenger Car

Gasoline

-1.60%

-14.14%

-3.66%

+63.41%

-10.14%

The 2032 emission factors for 2018v2 are the same as those from 2016v2 platform, with the following
exceptions. For 2018v2, MOVES3 was run for combination long haul trucks only for 2032 using an
updated age distribution, and the resulting emission factors were used. For 2018v2, representative county
assignments were adjusted in three North Carolina counties (Lee, Onslow, and Rockingham) to reflect
changes in inspection and maintenance programs in those counties. Also, to reflect changes in inspection
and maintenance programs in Tennessee, MOVES was rerun for three representative counties in that state
(Davidson, Hamilton, and Rutherford).

The fuels used are specific to each analytic year, the age distributions were projected to the analytic year,
and the meteorological data represented the year 2018. The resulting emission factors were combined
with analytic year activity data using SMOKE-MOVES run in a similar way as the base year. The
development of the analytic year activity data is described later in this section. CARB provided separate
emissions datasets for each analytic year. The CARB-provided emissions for 2032 were adjusted to match
the temporal and spatial patterns of the SMOKE-MOVES based emissions.

Analytic year 2032 VMT was developed as follows:

•	VMT were projected from 2018 to 2019 using VMT data from the FHWA county-level VM-2
reports. At the time of this study, these reports were available for each year up through 2019. EPA
calculated county-road type factors based on FHWA VM-2 county-level data for 2018 to 2019,
and county total factors were applied instead of county-road factors in states with significant
changes in road type classifications from year to year.

•	Total VMT were held flat from 2019 to 2021 to reflect impacts from the COVID-19 pandemic.
For 2021, VMT was re-split by fuel type according to fuel splits from the 2020NEI VMT. During
this step, VMT totals by county, source type, and road type were preserved, but fuel splits from
2020NEI were applied and the percentage of electric vehicles increased as a result.

•	VMT were then projected from 2021 to 2032 using AEO2022.

Annual VMT data from the AEO2022 reference case by fuel and vehicle type were used to project VMT
from 2021 to the projection years. Specifically, the following two AEO2022 tables were used:

•	Light Duty (LD): Light-Duty VMT by Technology Type (table #41):
https://www.eia. gov/outlooks/aeo/data/browser/#/?id=51-AEQ2022&sourcekev=0

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• Heavy Duty (HD): Freight Transportation Energy Use (table #49):
https://www.eia. gov/outlooks/aeo/data/browser/#/?id=58-
AE02022&cases=ref2022~aeo2020ref&sourcekev=0

To develop the VMT projection factors, total VMT for each MOVES fuel and vehicle grouping was
calculated for the years 2021 and 2032 based on the AEO-to-MOVES mappings above. From these totals,
2021-2032 VMT trends were calculated for each fuel and vehicle grouping. Those trends became the
national VMT projection factors. The AEO2022 tables include data starting from the year 2021. MOVES
fuel and vehicle types were mapped to AEO fuel and vehicle classes. The resulting 2021-to-analytic year
national VMT projection factors used for the 2018v2 platform are provided in Table 4-63. These factors
were adjusted to prepare county-specific projection factors for light duty vehicles based on human
population data available from the BenMAP model by county for the years 2021 and 203228
(https://www.woodsandpoole.com/. circa 2015). The purpose of this adjustment based on population
changes helps account for areas of the country that are growing more than others.

Table 4-63. Factors used to Project VMT to analytic years

SCC6

description

2021 to 2032 factor

220111

LD gas

1.187

220121

LD gas

1.187

220131

LD gas

1.187

220132

LD gas

1.187

220141

Buses gas

1.296

220142

Buses gas

1.296

220143

Buses gas

1.296

220151

MHD gas

1.296

220152

MHD gas

1.296

220153

MHD gas

1.296

220154

MHD gas

1.296

220161

HHD gas

0.486

220221

LD diesel

1.221

220231

LD diesel

1.221

220232

LD diesel

1.221

220241

Buses diesel

1.131

220242

Buses diesel

1.131

220243

Buses diesel

1.131

220251

MHD diesel

1.131

220252

MHD diesel

1.131

220253

MHD diesel

1.131

220254

MHD diesel

1.131

220261

HHD diesel

1.077

220262

HHD diesel

1.077

220341

Buses CNG

1.108

220342

Buses CNG

1.108

220343

Buses CNG

1.108

28 The final year of the population dataset used is 2030, and so 2030 population was used to represent 2032.

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SCC6

description

2021 to 2032 factor

220351

MHDCNG

1.108

220352

MHDCNG

1.108

220353

MHDCNG

1.108

220354

MHDCNG

1.108

220361

HHD CNG

1.046

220521

LD E-85

0.746

220531

LD E-85

0.746

220532

LD E-85

0.746

220921

LD Electric

6.707

220931

LD Electric

6.707

220932

LD Electric

6.707

Analytic year VPOP data were projected using calculations of VMT/VPOP ratios for each county, based
on 2017 NEI with MOVES3 fuels splits. Those ratios were then applied to the analytic year projected
VMT to estimate analytic year VPOP. Both VMT and VPOP were redistributed between the light duty car
and truck vehicle types (21/31/32) based on light duty vehicle splits from the EPA computed default
projection.

Hoteling hours were projected to the analytic years by calculating 2018v2 inventory HOTELING/VMT
ratios for each county for combination long-haul trucks on restricted roads only. Those ratios were then
applied to the analytic year projected VMT for combination long-haul trucks on restricted roads to
calculate analytic year hoteling. Some counties had hoteling activity but did not have combination long-
haul truck restricted road VMT in 2018v2; in those counties, the national AEO-based projection factor for
diesel combination trucks was used to project 2018v2 hoteling to the analytic years. This procedure gives
county-total hoteling for the analytic years. Each analytic year also has a distinct APU percentage based
on MOVES input data that was used to split county total hoteling to each SCC; for 2032, the APU
percentage is 31.72%.

Analytic year starts were calculated using 2018v2-based VMT ratios:

Analytic year STARTS = Analytic year VMT * (2018 STARTS / 2018 VMT by county+SCC6)

Analytic year ONI activity was calculated using a similar formula:

Analytic year ONI = Analytic year VMT * (2018 ONI / 2018 VMT by county+SCC6)

In California, onroad emissions in SMOKE-MOVES are adjusted to match CARB-provided data using
the same procedure described in Section 2.3.3. For 2018v2 platform, CARB provided new EMFAC
emissions for 2032.

4.3.3 Sources Outside of the United States (onroad_can, onroad_mex, othpt,
canada_ag, canada_og2D, ptfire_othna, othar, othafdust, othptdust)

This section discusses the projection of emissions from Canada and Mexico. Information about the base
year inventory used for these projections or the naming conventions can be found in Section 2.7. The
Canada and Mexico projections for 2032 are mostly the same as those in the 2016v2 platform, except

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with new SMOKE runs which map the emissions to 2018 calendar dates. The 2016v2 platform and
2018v2 platform use similar base year inventories in Canada and Mexico, allowing the previously
generated 2032 projections from 2016v2 platform to be reused for this study.

For the 2016vl platform, ECCC provided data from which Canadian analytic year projections could be
derived. These data includes emissions for 2015, 2023, and 2028 by pollutant, province, ECCC sub-class
code, and other source categories. ECCC sub-class codes are present in most Canadian inventories and are
similar to SCC, but more detailed for some types of sources and less detailed for other types of sources.
For most Canadian inventories, 2028 emissions inventories were projected from the 2016v2 base year
inventory using projection factors based on the ECCC sub-class level data from the 2016vl platform,
except with the 2015-to-2028 trend reduced to a 2016-to-2028 trend (i.e., reduce the total change by
1/13). Some Canadian emissions inventories then received an additional projection from 2028 to 2032,
with methodology for the 2032 projections varying by sector. Exceptions to this general procedure are
noted below. For example, ECCC sub-class level data could not be used to project inventories where the
sub-class codes changed from 2016vl to 2016v2. Fire emissions in Canada and Mexico in the
ptfire othna sector were not projected.

4.3.3.1	Canadian fugitive dust sources (othafdust, othptdust)

Canadian area source dust (othafdust)

For Canadian area source dust sources, ECCC sub-class level data from 2016vl platform was used to
project the 2016v2 base year inventory to 2028, and emissions from 2028 were used to represent the year
2032. As with the base year, the analytic year dust emissions are pre-adjusted, so analytic year othafdust
follows the same emissions processing methodology as the base year with respect to the transportable
fraction and meteorological adjustments.

Canadian point source dust (othptdust)

For this study, the base year emissions from the othptdust sector were held flat from the base year to the
analytic year.

4.3.3.2	Point Sources in Canada and Mexico (othpt, canada_ag,
canada_og2D)

Canada point agriculture and oil and gas emissions

For Canadian agriculture and upstream oil and gas sources, ECCC sub-class level data from 2016vl
platform was used to project the 2016v2 base year inventory to 2028, which was then used to represent
the year 2032. This procedure was applied to the entire canada ag and canada_og2D sectors, and to the
oil and gas elevated point source inventory in the othpt sector. For the ag inventories, the sub-class codes
are similar in detail to SCCs: fertilizer has a single sub-class code, and animal emissions categories
(broilers, dairy, horses, sheep, etc) each have a separate sub-class code.

Airports and other Canada point sources

For the Canada airports inventory in the othpt sector, projection factors to 2028 were based on total
airport emissions from the 2016vl Canada inventory by province and pollutant. 2028 emissions were then
used to represent 2032.

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During the development of the 2016vl platform, analytic year projections for stationary point sources
(excluding ag) were provided by ECCC for 2023 and 2028 rather than calculated by way of ECCC sub-
class code data. Additionally, projection information for many sub-class codes in the 2016v2 base year
stationary point inventories was not available in the 2016vl sub-class code data. Therefore, sub-class code
data was not used to project stationary point sources, and instead, those sources were projected using
factors based on total stationary (excluding ag and upstream oil and gas) point source emissions from
2016vl platform for 2015 and 2028, by province and pollutant. This is the same procedure that was used
for airports, except using different projection factors based on only the stationary sources. 2028 emissions
were used to represent 2032 for these point sources.

Mexico

The othpt sector includes a general point source inventory in Mexico which was updated for 2016v2
platform. Similar to the procedure for projecting Canadian stationary point sources, factors for projecting
from 2016 to 2028 were calculated from the 2016vl platform Mexico point source inventories by state
and pollutant and were then applied to the updated base year inventory to create a 2028 point source
inventory. Mexico point source emissions for 2028 were used to represent 2032.

4.3.3.3 Nonpoint sources in Canada and Mexico (othar)

Canadian stationary sources

For 2016vl platform, analytic year projections for stationary area sources in Canada were provided by
ECCC for 2023 and 2028 rather than calculated by way of ECCC sub-class code data. Additionally,
projection information for many sub-class codes in the 2016v2 base year stationary area source inventory
was not available in the 2016vl sub-class code data. Therefore, sub-class code data was not used to
project stationary area sources, and instead, those sources were projected using factors based on total
stationary area source emissions from 2016vl platform for 2015 and 2028, by province and pollutant.

This is the same procedure that was used for airports and stationary point sources, except using different
projection factors based on only the stationary area sources.

For 2016vl platform, ECCC provided an additional stationary area source inventory for 2028
representing electric power generation (EPG). According to ECCC, this inventory's emissions do not
double count the 2028 point source inventories, and it is appropriate to include this area source EPG
inventory in the othar sector as an additional standalone inventory in the analytic years. Therefore, the
2016vl platform area source EPG inventory was included in the 2018v2 platform analytic year case, with
2028 emissions used to represent 2032.

Canadian mobile sources

Projection information for mobile nonroad sources, including rail and CMV, is covered by the ECCC sub-
class level data for 2015 and 2028. ECCC sub-class level data from 2016vl platform was used to project
the 2016v2 base year inventory to 2028. For the nonroad inventory, the sub-class code is analogous to the
SCC7 level in U.S. inventories. For example, there are separate sub-class codes for fuels (e.g., 2-stroke
gasoline, diesel, LPG) and nonroad equipment sector (e.g., construction, lawn and garden, logging,
recreational marine) but not for individual vehicle types within each category (e.g., snowmobiles,
tractors). For rail, the sub-class code is closer to full SCCs in the NEI.

Instead of using 2028 mobile source emissions to represent 2032, additional projections out to 2032 were
applied to the Canada nonroad and rail inventories. For nonroad, national projection factors by fuel,
nonroad equipment sector, and pollutant were calculated from the 2016v2 platform US MOVES runs for

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2026 and 2032 (excluding California and Texas for which we did not use MOVES data) and applied to
the interpolated 2026 Canada nonroad inventory from 2016v2 platform. The 2026 Canada nonroad
inventory was used as the baseline for the 2032 projection rather than 2028, because we did not have a
MOVES run for 2028 which is consistent with the 2026 and 2032 MOVES3 runs performed for 2016v2
platform. For rail, factors for projecting 2026 Canadian rail from 2016v2 platform to 2032 were the same
as the factors used to project US rail emissions from 2026 to 2030 (used to represent 2032) in that
platform, which was based on the 2018 AEO.

Mexico

The othar sector includes two Mexico inventories, a stationary area source inventory and a nonroad
inventory. Similar to point, factors for projecting the 2016v2 base year inventories to 2028 were
calculated from the 2016vl platform Mexico area and nonroad inventories by state and pollutant. Separate
projections were calculated for the area and nonroad inventories. 2028 emissions were used to represent
2032, including for nonroad (unlike in Canada).

4.3.3.4 Onroad sources in Canada and Mexico (onroad_can,
onroad_mex)

For Canadian mobile onroad sources, projection information is covered by the ECCC sub-class level data
for 2015, 2023, and 2028. ECCC sub-class level data from 2016vl platform was used to project the
2016v2 base year inventory to 2028. For the onroad inventory, the sub-class code is analogous to the
SCC6+process level in U.S. inventories, in that it specifies fuel type, vehicle type, and process (e.g.,
brake, tire, exhaust, refueling), but not road type.

Instead of using 2028 mobile source emissions to represent 2032, additional projections out to 2032 were
applied to the Canada onroad inventory. National projection factors distinguishing gas from diesel, light
duty from heavy duty, refueling from non-refueling, and pollutant were calculated from the 2016v2
platform US MOVES runs for 2026 and 2032 (excluding California for which we did not use MOVES
data) and applied to the interpolated 2026 Canada onroad inventory. The 2026 Canada onroad inventory
was used as the baseline for the 2032 projection rather than 2028, because we did not have a MOVES3
run for 2028 which is consistent with the 2026 and 2032 MOVES runs performed for 2016v2 platform.

For Mexican mobile onroad sources, MOVES-Mexico was run to create emissions inventories for years
2028 and 2035, with 2032 emissions interpolated between 2028 and 2035. The 2035 MOVES-Mexico run
included diesel refueling whereas 2028 did not; thus diesel refueling emissions were excluded from the
2032 interpolation.

197


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5 Emission Summaries

Table 5-1 and Table 5-2 summarize annual emissions by sector for the 2018gg and 2032gg2 cases at the
national level by sector for the contiguous U.S. and for the portions of Canada and Mexico inside the
larger 12km domain (12US1) discussed in Section 3.1. Table 5-3 provides similar summaries for the 36-
km domain (36US3) for 2018 only, as boundary conditions based on 2018 emissions were also used in
2032. Note that totals for the 12US2 domain are not available here, but the sum of the U.S. sectors would
be essentially the same and only the Canadian and Mexican emissions would change according to how far
north and south the grids extend. Note that the afdust sector emissions here represent the emissions after
application of both the land use (transport fraction) and meteorological adjustments; therefore, this sector
is called "afdust adj" in these summaries. The afdust emissions in the 36km domain are smaller than
those in the 12km domain due to how the adjustment factors are computed and the size of the grid cells.
The onroad sector totals are post-SMOKE-MOVES totals, representing air quality model-ready emission
totals, and include CARB emissions for California. The cmv sectors include U.S. emissions within state
waters only; these extend to roughly 3-5 miles offshore and include CMV emissions at U.S. ports.
"Offshore" represents CMV emissions that are outside of U.S. state waters. The total of all US sectors is
listed as "Con U.S. Total."

State totals and other summaries are available in the reports area on the FTP site for the 2018v2 platform
(https://gaftp.epa.gov/Air/emismod/2018/v2/reports).

198


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Table 5-1. National by-sector CAP emissions for the 2018gg case, 12US1 grid (tons/yr)

Sector

CO

NH3

NOX

PM10

PM2 5

S02

voc

afdustadj







5,691,832

789,322





airports

489,039

0

131,779

9,813

8,576

16,492

54,939

cmv_clc2

24,431

86

168,566

4,622

4,480

655

6,674

cmv_c3

15,068

42

114,722

2,380

2,189

4,891

9,311

fertilizer



1,636,229











livestock



2,582,189









226,398

nonpt

1,927,267

102,898

739,250

572,589

475,154

166,399

818,185

nonroad

10,473,047

1,925

988,078

96,182

90,714

1,372

1,016,057

npoilgas

661,167

38

668,403

12,669

12,508

55,360

2,414,209

npsolvents

36

58

34

469

448

5

2,336,842

onroad

17,043,371

103,249

2,827,564

207,714

88,309

22,628

1,172,608

ptoilgas

200,740

434

385,649

13,663

13,047

39,003

232,995

ptagfire

421,836

93,685

17,935

59,968

38,050

7,451

63,726

ptegu

573,335

21,576

1,143,179

157,107

127,072

1,314,836

32,612

ptfire-rx

10,873,070

177,629

182,473

1,168,800

1,001,912

91,868

2,617,765

ptfire-wild

10,275,916

168,798

147,585

1,051,942

891,476

79,478

2,426,465

ptnonipm

1,378,771

60,793

894,993

388,475

242,515

561,234

766,021

rail

117,171

365

570,969

15,494

15,005

727

24,947

rwc

2,160,529

16,413

34,093

300,139

299,278

7,988

323,969

beis

3,902,690



974,463







25,755,648

Con. U.S. Total + beis

60,537,483

4,966,406

9,989,734

9,753,858

4,100,054

2,370,387

40,299,369

Can./Mex./Offshore















Sector

CO

NH3

NOX

PM10

PM2 5

S02

VOC

Canada ag



492,798









105,145

Canada oil and gas 2D

666

7

3,232

185

185

3,933

509,228

Canada othafdust







580,703

90,421





Canada othar

2,182,369

3,815

306,078

223,090

174,668

16,318

725,957

Canada onroadcan

1,661,932

7,156

331,485

23,592

11,282

1,531

134,046

Canada othpt

1,115,125

19,472

650,660

90,023

43,036

989,829

148,163

Canada othptdust







132,266

46,401





Canada ptfireothna

4,679,983

93,406

195,209

671,858

565,668

38,759

1,343,696

Canada CMV

11,104

37

96,622

1,716

1,594

2,941

5,409

Mexico othar

111,429

114,444

54,457

102,675

33,595

1,659

353,294

Mexico onroad mex

1,821,182

2,918

447,430

15,744

11,158

6,638

159,185

Mexico othpt

140,473

1,168

182,265

50,809

35,368

368,023

37,066

Mexico ptfire othna

438,065

8,465

17,524

57,762

49,343

3,612

126,265

Mexico CMV

0

0

0

0

0

0

0

Offshore cmv in Federal
waters

34,428

133

292,670

7,437

6,886

29,127

16,779

Offshore cmv outside
Federal waters

24,283

457

267,502

25,810

23,752

189,097

11,528

Offshore pt oilgas

51,872

8

49,962

636

635

462

38,833

Non-U.S. Total

12,272,911

744,285

2,895,097

1,984,306

1,093,993

1,651,929

3,714,595

199


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Table 5-2. National by-sector CAP emissions for the 2032gg2 case, 12US1 grid (tons/yr)

Sector

CO

NH3

NOX

PM10

PM2 5

S02

voc

afdust adj







5,780,588

809,684





airports

570,574

0

164,926

10,686

9,373

20,039

63,302

cmv clc2

25,299

50

97,145

2,695

2,611

374

3,779

cmv c3

21,045

59

112,190

3,331

3,064

6,812

13,167

fertilizer



1,636,229











livestock



2,741,401









239,799

nonpt

1,939,962

104,043

712,933

581,503

492,884

123,628

735,427

nonroad

11,602,438

2,249

565,879

53,184

49,329

1,127

827,539

np oilgas

621,290

26

568,387

12,497

12,350

76,245

2,283,192

np solvents

8,409,394

98,770

784,553

188,234

49,249

18,159

518,947

onroad

197,719

352

339,405

15,329

14,443

47,938

237,476

pt oilgas

421,836

93,685

17,935

59,968

38,050

7,451

63,726

ptagfire

308,100

28,078

383,178

73,294

66,046

294,886

32,246

ptegu

10,873,070

177,629

182,473

1,168,800

1,001,912

91,868

2,617,765

ptfire-rx

10,275,916

168,798

147,585

1,051,942

891,476

79,478

2,426,465

ptfire-wild

1,393,746

68,428

847,781

377,960

240,155

501,935

757,877

ptnonipm

111,045

347

405,629

10,069

9,733

394

15,427

rail

2,091,084

16,135

35,602

290,785

289,904

7,223

318,652

rwc

38

65

38

527

503

6

2,524,685

beis

3,902,690



974,463







25,755,648

Con. U.S. Total + beis

52,765,247

5,136,344

6,340,103

9,681,390

3,980,767

1,277,563

39,435,120

Can./Mex./Offshore















Sector

CO

NH3

NOX

PM10

PM2 5

S02

VOC

Canada ag



667,454









104,909

Canada oil and gas 2D

510

7

1,205

136

136

3,703

470,211

Canada othafdust







711,618

110,490





Canada other

2,204,204

3,696

224,546

214,031

155,763

16,178

753,048

Canada onroad can

1,176,889

6,506

156,141

25,861

8,339

847

67,063

Canada othpt

1,169,373

23,880

456,857

77,938

46,049

868,773

163,728

Canada othptdust







132,266

46,401





Canada ptfire othna

4,679,983

93,406

195,209

671,858

565,668

38,759

1,343,696

Canada CMV

12,884

43

81,922

1,957

1,816

3,415

6,188

Mexico other

132,253

110,416

75,376

109,103

37,151

2,090

434,481

Mexico onroad mex

1,595,367

4,193

383,169

20,996

14,140

9,390

173,311

Mexico othpt

136,038

1,524

209,202

66,914

46,178

306,258

51,730

Mexico ptfire othna

438,065

8,465

17,524

57,762

49,343

3,612

126,265

Mexico CMV

0

0

0

0

0

0

0

Offshore cmv in Federal
waters

47,504

177

244,007

9,995

9,221

42,425

23,002

Offshore cmv outside
Federal waters

34,333

333

377,167

18,817

17,315

50,004

16,272

Offshore ptoilgas

51,872

8

49,962

636

635

462

38,833

Non-U.S. Total

11,679,275

920,109

2,472,288

2,119,885

1,108,644

1,345,918

3,772,736

200


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Table 5-3. National by-sector CAP emissions for the 2018gg case, 36US3 grid (tons/yr)

Sector

CO

NH3

NOX

PM10

PM2_5

S02

voc

afdustadj







5,696,028

789,743





airports

489,904

0

131,938

9,843

8,602

16,517

55,044

cmv_clc2

24,434

86

168,585

4,623

4,480

655

6,674

cmv_c3

15,289

43

116,700

2,410

2,218

4,964

9,426

fertilizer



1,636,229











livestock



2,582,191









226,399

nonpt

1,927,717

102,919

740,303

572,647

475,204

166,409

818,460

nonroad

10,477,852

1,925

988,242

96,215

90,744

1,372

1,016,923

npoilgas

661,167

38

668,403

12,669

12,508

55,360

2,414,209

npsolvents

36

58

34

469

448

5

2,336,846

onroad

17,049,876

103,264

2,828,221

207,767

88,334

22,629

1,173,091

ptoilgas

200,740

434

385,649

13,663

13,047

39,003

232,995

ptagfire

421,836

93,685

17,935

59,968

38,050

7,451

63,726

ptegu

573,370

21,576

1,143,369

157,110

127,073

1,314,836

32,616

ptfire-rx

10,873,070

177,629

182,473

1,168,800

1,001,912

91,868

2,617,765

ptfire-wild

10,275,916

168,798

147,585

1,051,942

891,476

79,478

2,426,465

ptnonipm

1,378,776

60,793

895,044

388,517

242,526

561,234

766,024

rail

117,171

365

570,969

15,494

15,005

727

24,947

rwc

2,184,698

16,441

34,564

301,273

300,412

8,062

324,549

beis

3,987,520



996,046







26,186,779

36US3 U.S. Total + beis

60,659,372

4,966,472

10,016,061

9,759,438

4,101,784

2,370,572

40,732,937

Can./Mex./Offshore















Sector

CO

NH3

NOX

PM10

PM2 5

S02

VOC

Canada ag



508,077









107,843

Canada oil and gas 2D

730

7

3,538

203

203

4,420

604,562

Canada othafdust







583,720

90,878





Canada othar

2,342,203

4,111

340,782

236,933

186,083

17,052

763,150

Canada onroadcan

1,731,621

7,433

348,542

24,601

11,819

1,587

139,162

Canada othpt

1,378,449

21,382

831,679

102,194

50,204

1,123,746

203,319

Canada othptdust







129,213

45,052





Canada ptfireothna

7,465,807

151,948

311,054

1,066,014

902,171

61,148

2,114,343

Canada CMV

13,594

45

119,577

2,128

1,974

4,035

6,724

Mexico othar

1,638,884

574,281

216,199

451,850

243,750

12,232

1,546,910

Mexico onroad mex

6,240,630

10,795

1,512,464

80,530

61,809

28,020

553,804

Mexico othpt

426,418

3,532

463,774

198,039

132,579

1,538,614

115,851

Mexico ptfire othna

5,958,233

101,557

285,718

955,132

629,885

38,914

1,853,619

Mexico CMV

64,665

1

205,403

16,300

15,100

109,886

8,832

Offshore cmv in Federal
waters

36,343

161

312,748

9,053

8,374

40,877

17,652

Offshore cmv outside
Federal waters

91,453

1,236

1,040,036

95,917

88,271

709,026

41,730

Offshore pt oilgas

51,872

8

49,962

636

635

462

38,833

Annual Total

27,440,903

1,384,575

6,041,477

3,952,464

2,468,786

3,690,018

8,116,334

201


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6 References

Adelman, Z. 2012. Memorandum: Fugitive Dust Modeling for the 2008 Emissions Modeling Platform.
UNC Institute for the Environment, Chapel Hill, NC. September 28, 2012.

Adelman, Z. 2016. 2014 Emissions Modeling Platform Spatial Surrogate Documentation. UNC Institute
for the Environment, Chapel Hill, NC. October 1, 2016. Available at
https://gaftp.epa.gov/Air/emismod/2014/vl/spatial surrogates/.

Adelman, Z., M. Omary, Q. He, J. Zhao and D. Yang, J. Boylan, 2012. "A Detailed Approach for
Improving Continuous Emissions Monitoring Data for Regulatory Air Quality Modeling."
Presented at the 2012 International Emission Inventory Conference, Tampa, Florida. Available
from http://www.epa.gOv/ttn/chief/conference/ei20/index.html#ses-5.

Appel, K.W., Napelenok, S., Hogrefe, C., Pouliot, G., Foley, K.M., Roselle, S.J., Pleim, J.E., Bash, J.,
Pye, H.O.T., Heath, N., Murphy, B., Mathur, R., 2018. Overview and evaluation of the
Community Multiscale Air Quality Model (CMAQ) modeling system version 5.2. In Mensink C.,
Kallos G. (eds), Air Pollution Modeling and its Application XXV. ITM 2016. Springer
Proceedings in Complexity. Springer, Cham. Available at https://doi.org/10.1007/978-3-319-
57645-9 11.

Bash, J.O., Baker, K.R., Beaver, M.R., Park, J.-H., Goldstein, A.H., 2016. Evaluation of improved land
use and canopy representation in BEIS with biogenic VOC measurements in California. Available
from http J/www, geosci-model-dev. net/9/2191/2016/.

BEA, 2012. "2013 Global Outlook projections prepared by the Conference Board in November 2012".
U.S. Bureau of Economic Analysis. Available from: http://www.conference-
b oard. org/data/ gl ob aloutl ook. cfm.

Bullock Jr., R, and K. A. Brehme (2002) "Atmospheric mercury simulation using the CMAQ model:

formulation description and analysis of wet deposition results." Atmospheric Environment 36, pp
2135-2146. Available at https://doi.org/10.1016/S1352-2310(02^)00220-0.

California Air Resources Board (CARB): ORGPROF - Organic chemical profiles for source categories,
2018. https://ww2.arb.ca.gov/speciation-profiles-used-carb-modeling .

California Air Resources Board (CARB): 2005 Architectural Coatings Survey - Final Report, 2007.

California Air Resources Board (CARB): 2010 Aerosol Coatings Survey Results, 2012.

California Air Resources Board (CARB): 2014 Architectural Coatings Survey - Draft Data Summary,
2014.

California Air Resources Board (CARB): Final 2015 Consumer & Commercial Product Survey Data
Summaries, 2019.

Coordinating Research Council (CRC). Report A-100. Improvement of Default Inputs for MOVES and
SMOKE-MOVES. Final Report. February 2017. Available at http://crcsite.wpengine.com/wp-
content/uploads/2019/05/ERG FinalReport CRCA100 28Feb2017.pdf.

202


-------
Coordinating Research Council (CRC). Report A-l 15. Developing Improved Vehicle Population Inputs
for the 2017 National Emissions Inventory. Final Report. April 2019. Available at
http://crcsite.wpengine.eom/wp-content/uploads/2019/05/CRC-Proiect-A-115-Final-
Report 20190411.pdf.

Drillinginfo, Inc. 2015. "DI Desktop Database powered by HPDI." Currently available from
https://www.enverus.com/.

England, G., Watson, J., Chow, J., Zielenska, B., Chang, M., Loos, K., Hidy, G., 2007. "Dilution-Based
Emissions Sampling from Stationary Sources: Part 2— Gas-Fired Combustors Compared with
Other Fuel-Fired Systems," Journal of the Air & Waste Management Association, 57:1, 65-78,
DOI: 10.1080/10473289.2007.10465291. Available at
https://www.tandfonline.eom/doi/abs/10.1080/10473289.2007.10465291.

EPA, 2017. Light-Duty Vehicle, Light-Duty Truck, and Medium-Duty Passenger Vehicle Tier 2 Exhaust
Emission Standards. Office of Transportation and Air Quality, Ann Arbor, MI 48105. Available
at: https://www.epa.gov/emission-standards-reference-guide/epa-emission-standards-light-dutv-
vehicles-and-trucks-and.

EPA, 2008. Regulatory Impact Analysis: Control of Emissions of Air Pollution from Locomotive Engines
and Marine Compression Ignition Engines Less than 30 Liters Per Cylinder. EPA420-R-08-001.
Available at: https://nepis.epa.gov/Exe/ZyPDF.cgi/P10023 S4.PDF?Dockev=P 10023S4.PDF.

EPA, 2012d. Preparation of Emission Inventories for the Version 5.0, 2007 Emissions Modeling Platform
Technical Support Document. Available from: https://www.epa.gov/air-emissions-modeling/2007-
version-50-technical-support-document.

EPA, 2013rwc. "2011 Residential Wood Combustion Tool version 1.1, September 2013", available from
US EPA, OAQPS, EIAG.

EPA, 2015b. Draft Report Speciation Profiles and Toxic Emission Factors for Nonroad Engines. EPA-
420-R-14-028. Available at

https://cfpub.epa.gov/si/si public record Report.cfm?dirEntryId=309339&CFID=83476290&CF
TOKEN=35281617.

EPA, 2015c. Speciation of Total Organic Gas and Particulate Matter Emissions from On-road Vehicles in
MOVES2014. EPA-420-R-15-022. Available at
https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockev=Pl OONOJG.pdf.

EPA, 2016. SPECIATE Version 4.5 Database Development Documentation, U.S. Environmental

Protection Agency, Office of Research and Development, National Risk Management Research
Laboratory, Research Triangle Park, NC 27711, EPA/600/R-16/294, September 2016. Available at
https://www.epa.gov/sites/production/files/2016-Q9/documents/speciate 4.5.pdf.

EPA, 2017. Additional Updates to Emissions Inventories for the Version 6.3, 2011 Emissions Modeling
Platform for the Year 2023 technical support document. Available at:
https://www.epa.gov/sites/production/files/2Q17-
ll/documents/2011v6.3 2023en update emismod tsd oct2017.pdf.

EPA, 2018. AERMOD Model Formulation and Evaluation Document. EPA-454/R-18-003. U.S.

Environmental Protection Agency, Research Triangle Park, North Carolina 27711. Available at
https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockev=P100UT95.PDF.

203


-------
EPA, 2018. 2014 National Emission Inventory, version 2 Technical Support Document. U.S.

Environmental Protection Agency, OAQPS, Research Triangle Park, NC 27711. Available at:
https://www.epa.gov/air-emissions-inventories/2014-national-emissions-inventory-nei-technical-
support-document-tsd.

EPA, 2019. Final Report, SPECIATE Version 5.0, Database Development Documentation, Research
Triangle Park, NC, EPA/600/R-19/988. Available at https://www.epa.gov/air-emissions-
modeling/ speciate-51 -and-5 O-addendum-and-final-report.

EPA, 2020. Population and Activity of Onroad Vehicles in MOVES3. EPA-420-R-20-023. Office of

Transportation and Air Quality. US Environmental Protection Agency. Ann Arbor, MI. November
2020. Available under the MOVES3 section at https://www.epa.gov/moves/moves-technical-
reports.

EPA, 2021. Technical Support Document (TSD) Preparation of Emissions Inventories for the 2016v2

North American Emissions Modeling Platform. Available at https://www.epa.gov/air-emissions-
modeling/2016v2-platform.

EPA, 2021b. 2017 National Emission Inventory: January 2021 Updated Release, Technical Support

Document. U.S. Environmental Protection Agency, OAQPS, Research Triangle Park, NC 27711.
Available at: https://www.epa.gov/air-emissions-inventories/2017-national-emissions-inventory-
nei-technical-support-document-tsd.

EPA, 2021c. Technical Support Document (TSD) Preparation of Emissions Inventories for the 2016vl
North American Emissions Modeling Platform. Available at https://www.epa.gov/air-emissions-
modeling/2016-version-l-technical-support-document.

EPA, 2021d. 2017 National Emissions Inventory (NEI), Research Triangle Park, NC, January 2021.
https://www.epa.gov/air-emissions-inventories/2017-national-emissions-inventory-nei-data.

EPA, 2022a. Technical Support Document (TSD) Preparation of Emissions Inventories for the 2018
North American Emissions Modeling Platform. EPA-454/B-22-005. Available at
https://www.epa.gov/air-emissions-modeling/2018-emissions-modeling-platform.

EPA, 2022b. 2019 National Emissions Inventory (NEI) Technical Support Document: Point Data
Category, Research Triangle Park, NC. EPA-454/R-22-001. Available at:
https://www.epa.gov/air-emissions-modeling/2019-nei-technical-support-documentation.

EPA, 2023a. Technical Support Document (TSD) Preparation of Emissions Inventories for the 2016v3
North American Emissions Modeling Platform. EPA-454/B-23-002. Available at
https://www.epa.gov/air-emissions-modeling/2016v3-platform.

EPA, 2023b. 2020 National Emissions Inventory (NEI), Research Triangle Park, NC, March 2023.
https://www.epa.gov/air-emissions-inventories/2020-national-emissions-inventory-nei-data.

ERG, 2014a. Develop Mexico Future Year Emissions Final Report. Available at

https://gaftp.epa.gov/air/emismod/201 l/v2platform/2011 emissions/Mexico Emissions WA%204-
09 final report 121814.pdf.

ERG, 2016b. "Technical Memorandum: Modeling Allocation Factors for the 2014 Oil and Gas Nonpoint
Tool." Available at https://gaftp.epa.gov/air/emismod/2014/vl/spatial surrogates/oil and gas/.

ERG, 2017. "Technical Report: Development of Mexico Emission Inventories for the 2014 Modeling

Platform." Available at https://gaftp.epa.gov/Air/ernismod/2014/v2/2014fd/ernissions/EPA%205-
18%20Report Clean%20Final 01042017.pdf.

204


-------
ERG, 2018. Technical Report: "2016 Nonpoint Oil and Gas Emission Estimation Tool Version 1.0".
Available at

https://gaftp.epa.gov/air/emismod/2016/vl/reports/2016%20Nonpoint%200il%20and%20Gas%2
0Emission%20Estimation%20Tool%20Vl 0%20December 2018.pdf.

ERG, 2019a. "2017 Nonpoint Oil and Gas Emission Estimation Tool Revisions" Available from:

https://gaftp.epa.gov/air/nei/2017/doc/supporting data/nonpoint/2017%200il%20and%20Gas%20
Memos.zip.

ERG, 2019b. Category 1 and 2 Commercial Marine Emissions Inventory. Available from:

https://www.epa.gov/sites/default/files/2019-l 1/cmv methodology documentation.zip.

ERG, 2019c. 2016 versus 2017 entrance and clearance data. Available

from:https://gaftp.epa.gov/Air/emismod/2016/v2/reports/cmv/EandC 2016 to 2017 Activity Rat
ios.pdf.

ERG, 2021. "Historical Nonpoint Oil and Gas Emission Inventory Development for 2018".

The Freedonia Group, 2016. Solvents, Industry Study #3429.

Foley et al., 2023. 2002-2017 anthropogenic emissions data for air quality modeling over the United
States. Available at

https://www.sciencedirect.com/science/article/pii/S23523409230014037via%3Dihub.

Frost & Sullivan, 2010. "Project: Market Research and Report on North American Residential Wood
Heaters, Fireplaces, and Hearth Heating Products Market (P.O. # PO1-IMP403-F&S). Final
Report April 26, 2010", pp. 31-32. Prepared by Frost & Sullivan, Mountain View, CA 94041.

Gkatzelis, G.I., Coggon, M.M., McDonald, B.C., Peischl, J., Aikin, K.C., Gilman, J.B., Trainer, M.,

Warneke, C. Identifying Volatile Chemical Product Tracer Compounds in US Cities. Environ. Sci.
Technol. 2021, 55 (1), 188-199.

Houck, 2011. "Dirty- vs. Clean-Burning? What percent of freestanding wood heaters in use in the U.S.
today are still old, uncertified units?" Hearth and Home, December 2011.

Hutchins, M.L., Holkzworth, R.H., Brundell, J.B., and Rodger, C.J., 2012. Relative detection efficiency
of the World Wide Lightning Location Network. Available from
http://wwlln.net/publications/Hutchins Detection Efficiency RadioSci 2012.pdf.

Kang et al., 2022. Assessing the Impact of Lightning NOx Emissions in CMAQ using Lightning Flash
Data from WWLLN over the Contiguous United States. Available from
https://doi.org/10.3390/atmosl3081248.

Khare, P., and Gentner, D. R., 2018. Considering the future of anthropogenic gas-phase organic

compound emissions and the increasing influence of non-combustion sources on urban air quality,
Atmos ChemPhys, 18, 5391-5413, 10.5194/acp-18-5391-2018.

Luecken D., Yarwood G, Hutzell WT, 2019. Multipollutant modeling of ozone, reactive nitrogen and
HAPs across the continental US with CMAQ-CB6. Atmospheric environment. 2019 Mar
15;201:62-72.

205


-------
Mansouri, K., Grulke, C. M., Judson, R. S., and Williams, A. J., 2018. OPERA models for predicting
physicochemical properties and environmental fate endpoints, J Cheminformatics, 10,

10.1186/sl 3321-018-0263-1.

McCarty, J.L., Korontzi, S., Jutice, C.O., and T. Loboda. 2009. The spatial and temporal distribution of
crop residue burning in the contiguous United States. Science of the Total Environment, 407 (21):
5701-5712. Available at

https://www.sciencedirect.com/science/article/abs/pii/S13522310080001377via%3Dihub.

MDNR, 2008. "A Minnesota 2008 Residential Fuelwood Assessment Survey of individual household
responses". Minnesota Department of Natural Resources. Available from
http://files.dnr.state.mn.us/forestry/um/residentialfuelwoodassessment07 08.pdf.

NCAR, 2016. FIRE EMISSION FACTORS AND EMISSION INVENTORIES, FINN Data, downloaded
2014 SAPRC99 version from https://www.acom.ucar.edu/Data/fire/.

NESCAUM, 2006. "Assessment of Outdoor Wood-fired Boilers". Northeast States for Coordinated Air
Use Management (NESCAUM) report. Available from

http://www.nescaum.org/documents/assessment-of-outdoor-wood-fired-boilers/2006-1031-owb-
report revised-iune2006-appendix.pdf.

NYSERDA, 2012. "Environmental, Energy Market, and Health Characterization of Wood-Fired Hydronic
Heater Technologies, Final Report". New York State Energy Research and Development
Authority (NYSERDA). Available from: https://www-nyserda-ny-gov.webpkgcache.com/doc/-
/s/www.nyserda.ny.gov/-

/media/Proiect/Nvserda/Files/Publications/Research/Environmental/Wood-Fired-Hvdronic-
Heater-Tech-Summary.pdf.

Pechan, 2001. E.H. Pechan & Associates, Inc., Control Measure Development Support—Analysis of
Ozone Transport Commission Model Rules, Springfield, VA, prepared for the Ozone Transport
Commission, Washington, DC, March 31, 2001. Available at

https://otcair.Org/upload/Documents/Reports/Control%20Measure%20Development%20Support.p
df.

Pouliot, G., H. Simon, P. Bhave, D. Tong, D. Mobley, T. Pace, and T. Pierce. 2010. "Assessing the
Anthropogenic Fugitive Dust Emission Inventory and Temporal Allocation Using an Updated
Speciation of Particulate Matter." International Emission Inventory Conference, San Antonio, TX.
Available at http://www3.epa.gov/ttn/chief/conference/eil9/session9/pouliot pres.pdf.

Pouliot, G. and J. Bash, 2015. Updates to Version 3.61 of the Biogenic Emission Inventory System
(BEIS). Presented at Air and Waste Management Association conference, Raleigh, NC, 2015.

Pouliot G, Rao V, McCarty JL, Soja A. Development of the crop residue and rangeland burning in the

2014 National Emissions Inventory using information from multiple sources. Journal of the Air &
Waste Management Association. 2017 Apr 27;67(5):613-22.

Pye, H. O. T.; Pouliot, G. A., 2012. Modeling the role of alkanes, polycyclic aromatic hydrocarbons, and
their oligomers in secondary organic aerosol formation. Environ. Sci. Technol. 2012, 46,
6041-6047.

206


-------
Raffuse, S., D. Sullivan, L. Chinkin, S. Larkin, R. Solomon, A. Soja, 2007. Integration of Satellite-
Detected and Incident Command Reported Wildfire Information into BlueSky, June 27, 2007.
Available at: http://getbluesky.org/smartfire/docs.cfm.

Ramboll (Shah, T., Yarwood G.,) and EPA (Eyth, A., Strum, M), 2017. COMPOSITION OF ORGANIC
GAS EMISSIONS FROM FLARING NATURAL GAS, Presented at the 2017 International
Emission Inventory Conference, August 18, 2017. Available at

https://www.epa.gov/sites/production/files/2017-ll/documents/organic gas.pdf. Additional Memo
from Ramboll Environ to EPA (same title as presentation) dated September 23, 2016.

Ramboll, 2020. https://github.com/CMASCenter/Speciation-

Tool/blob/master/docs/Ramboll sptool mapping updates AE7 AE8 24Mar2020 final full.pdf.

Reichle, L., R. Cook, C. Yanca, D. Sonntag, 2015. "Development of organic gas exhaust speciation

profiles for nonroad spark-ignition and compression-ignition engines and equipment", Journal of
the Air & Waste Management Association, 65:10, 1185-1193, DOI:

10.1080/10962247.2015.1020118. Available at https://doi.org/10.1080/10962247.2015.102Q118.

Reff, A., Bhave, P., Simon, H., Pace, T., Pouliot, G., Mobley, J., Houyoux. M. "Emissions Inventory of
PM2.5 Trace Elements across the United States", Environmental Science & Technology 2009 43
(15), 5790-5796, DOI: 10.1021/es802930x. Available at https://doi.org/10.1021/es802930x.

Sarwar, G., S. Roselle, R. Mathur, W. Appel, R. Dennis, "A Comparison of CMAQ HONO predictions
with observations from the Northeast Oxidant and Particle Study", Atmospheric Environment 42
(2008) 5760-5770). Available at https://doi.Org/10.1016/i.atmosenv.2007.12.065.

Schauer, J., G. Lough, M. Shafer, W. Christensen, M. Arndt, J. DeMinter, J. Park, "Characterization of

Metals Emitted from Motor Vehicles," Health Effects Institute, Research Report 133, March 2006.
Available at https://www.healtheffects.org/publication/characterization-metals-emitted-motor-
vehicles.

Seltzer, K. M., Pennington, E., Rao, V., Murphy, B. N., Strum, M., Isaacs, K. K., and Pye, H. O. T., 2021.
Reactive organic carbon emissions from volatile chemical products, Atmos. Chem. Phys., 21,
5079-5100, https://doi.org/10.5194/acp-21-5079-2021.

Skamarock, W., J. Klemp, J. Dudhia, D. Gill, D. Barker, M. Duda, X. Huang, W. Wang, J. Powers, 2008.
A Description of the Advanced Research WRF Version 3. NCAR Technical Note. National Center
for Atmospheric Research, Mesoscale and Microscale Meteorology Division, Boulder, CO. June
2008. Available at: https://opensky.ucar.edU/islandora/obiect/technotes:500.

Sullivan D.C., Raffuse S.M., Pryden D.A., Craig K.J., Reid S.B., Wheeler N.J.M., Chinkin L.R., Larkin
N.K., Solomon R., and Strand T. (2008) Development and applications of systems for modeling
emissions and smoke from fires: the BlueSky smoke modeling framework and SMARTFIRE: 17th
International Emissions Inventory Conference, Portland, OR, June 2-5.

Swedish Environmental Protection Agency, 2004. Swedish Methodology for Environmental Data;
Methodology for Calculating Emissions from Ships: 1. Update of Emission Factors.

207


-------
U.S. Census Bureau, Economy Wide Statistics Division, 2018. County Business Patterns, 2018.
https://www.census.gov/programs-survevs/cbp/data/datasets.html.

U.S. Bureau of Labor Statistics, 2020. Producer Price Index by Industry, retrieved from FRED, Federal
Reserve Bank of St. Louis. https://fred.stlouisfed.Org/categories/31.

U.S. Census Bureau, 2011 Paint and Allied Products - 2010, MA325F(10).

https://www.census.gov/data/tables/time-series/econ/cir/ma325f.html.

U.S. Census Bureau, 2021. 2018 Annual Survey of Manufacturers (ASM), Washington D.C., USA.
https://www.census.gov/data/developers/data-sets/Annual-Survev-of-Manufactures.html.

U.S. Department of Transportation and the U.S. Department of Commerce, 2015. 2012 Commodity Flow
Survey, EC12TCF-US. https://www.census.gov/library/publications/2015/econ/ecl2tcf-us.html.

U.S. Energy Information Administration, 2019. The Distribution of U.S. Oil and Natural Gas Wells by
Production Rate, Washington, DC. https://www.eia.gov/petroleum/wells/.

Wang, Y., P. Hopke, O. V. Rattigan, X. Xia, D. C. Chalupa, M. J. Utell. (2011) "Characterization of

Residential Wood Combustion Particles Using the Two-Wavelength Aethalometer", Environ. Sci.
Technol., 45 (17), pp 7387-7393. Available at https://doi.org/10.1021/es2013984.

Weschler, C. J., andNazaroff, W. W., 2008. Semivolatile organic compounds in indoor environments,
Atmos Environ, 42, 9018-9040.

Wiedinmyer, C., 2001. NCAR BVOC Enclosure Database. National Center for Atmospheric Research,
Boulder, CO.

Wiedinmyer, C., S.K. Akagi, R.J. Yokelson, L.K. Emmons, J.A. Al-Saadi3, J. J. Orlando1, and A. J. Soja.
(2011) "The Fire INventory from NCAR (FINN): a high resolution global model to estimate the
emissions from open burning", Geosci. Model Dev., 4, 625-641. http://www.geosci-model-
dev.net/4/625/2011/ doi: 10.5194/gmd-4-625-2011.

Wilson, Barry Tyler; Lister, Andrew J.; Riemann, Rachel I.; Griffith, Douglas M. 2013a. Live tree species
basal area of the contiguous United States (2000-2009). Newtown Square, PA: USD A Forest
Service, Rocky Mountain Research Station. https://doi.org/10.2737/RDS-2013-0013.

Wilson, Barry Tyler; Woodall, Christopher W.; Griffith, Douglas M. 2013b. Forest carbon stocks of the
contiguous United States (2000-2009). Newtown Square, PA: U.S. Department of Agriculture,
Forest Service, Northern Research Station. https://doi.org/10.2737/RDS-2013-00Q4.

WRAP / Ramboll, 2019. Revised Final Report: Circa-2014 Baseline Oil and Gas Emission Inventory for
the WESTAR-WRAP Region, September 2019. Available at:
http://www.wrapair2.org/pdf/WRAP OGWG Report Baseline 17Sep2019.pdf.

WRAP / Ramboll, 2020. Revised Final Report: 2028 Future Year Oil and Gas Emission Inventory for
WESTAR-WRAP States - Scenario #1: Continuation of Historical Trends
http://www.wrapair2.org/pdf/WRAP OGWG 2028 OTB RevFinalReport 05March2020.pdf.

208


-------
Yarwood, G., J. Jung,, G. Whitten, G. Heo, J. Mellberg, and M. Estes,2010: Updates to the Carbon Bond
Chemical Mechanism for Version 6 (CB6). Presented at the 9th Annual CMAS Conference,
Chapel Hill, NC. Available at

https://www.cmascenter.org/conference/2010/abstracts/emery updates carbon 2010.pdf.

Zhu, Henze, et al, 2013. "Constraining U.S. Ammonia Emissions using TES Remote Sensing
Observations and the GEOS-Chem adjoint model", Journal of Geophysical Research:
Atmospheres, 118: 1-14. Available at https://doi.org/10.1002/igrd.50166.

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United States	Office of Air Quality Planning and Standards	Publication No. EPA-454/B-23-003

Environmental Protection	Air Quality Assessment Division	September 2023

Agency	Research Triangle Park, NC

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