CHAPTER 3 

BASE YEAR AND FUTURE EMISSIONS 

Introduction

Emissions Inventories 

Base Year Emissions

Future Emissions 

Chapter 3 Base Year and Future Emissions 

3 - 1 

INTRODUCTION 

This chapter summarizes emissions occurring in the Basin during the base year 1997, 

and projected emissions in the years 2006, 2010, 2020. More detailed emission data 

analyses are presented in Appendix III of the 2003 AQMP. Additional emission 

inventories for other interim years (i.e., 1990, 1995, 2000, 2002, 2003, 2005, 2007, and 

2008) are also developed. These inventory years are selected to comply with federal and 

state Clean Air Act requirements. Under the federal and state Clean Air Acts, the 

District is required to report the Basin’s emission reduction progress for nonattainment 

pollutants. The base year to measure the Basin’s progress is 1990 for both the federal 

and state Clean Air Acts. A 1990 emission inventory was reconstructed to reflect the 

most recent inventory methodologies. Adopted air quality rules and regulations have 

current and future compliance dates. The 1997 base year emissions inventory reflects 

adopted air regulations with current compliance dates as of 1997; whereas future 

baseline emissions inventories are based on adopted air regulations with both current and 

future compliance dates. A list of South Coast Air Quality Management District 

(District) rules and regulations that are part of the base year and future-year baseline 

emissions inventories is presented in Appendix III of the 2003 AQMP. The District is 

committed to implement these rules that are incorporated in the 2003 AQMP baseline 

emissions inventories. 

The emissions inventory is divided into four major classifications: point, area, off-road, 

and on-road sources. The 1997 base year point source emissions are based principally 

on reported data from facilities. The area source and off-road emissions are estimated 

jointly by the California Air Resources Board (CARB) and the District. The on-road 

emissions are calculated using the CARB EMFAC2002 emission factors and the 

transportation activity data provided by SCAG from their 2001 Regional Transportation 

Plan (2001 RTP). The 1990 inventories were reconstructed/backcasted based on the 

same general methodology as the 1997 inventory so as to reflect current knowledge. For 

example, EMFAC2002 was applied to the 1990 vehicle activity data to backcast 1990 

on-road mobile emissions. This approach provides a more consistent basis for 

evaluation of emission reduction progress. 

The future emission forecasts are based on demographic and economic growth 

projections provided by the Southern California Association of Governments (SCAG). 

In addition, emission reductions resulting from CARB and District regulations adopted 

by October 31, 2002 are included in the emission forecasts. 
Final 2003 AQMP 

3 - 2 

EMISSIONS INVENTORIES 

Baseline emissions data presented in this chapter are based on average annual day 

emissions (i.e., total annual emissions divided by 365 days) and seasonally adjusted 

planning inventory emissions. The 2003 AQMP uses annual average day emissions to 

estimate the cost-effectiveness of a control measure, to rank control measure 

implementation, and to perform PM10 modeling and analysis. The planning inventory 

emissions developed to capture the emission levels during a respective poor air quality 

season are used to report emission reduction progress as required by the federal and state 

Clean Air Acts. Three inventories are prepared for the 2003 AQMP for the purpose of 

regulatory and SIP performance tracking and transportation conformity: an annual 

average inventory, a summer planning inventory, and a winter planning inventory. 

Detailed descriptions of the base year and future baseline emission inventories are 

presented in Appendix III of the 2003 AQMP - Base Year and Future Year Emission 

Inventories. 

Attachment F to Appendix III has been added due to the recent significance placed on 

diesel emissions, showing various source categories’ emissions associated with 

combustion of diesel fuel. 

Stationary Sources 

Stationary sources can be divided into two major subcategories: point and area sources. 

Point sources are generally large emitters with one or more emission sources at a 

permitted facility with an identified location (e.g., power plants, refineries). Area 

sources generally consist of many small emission sources (e.g., residential water heaters, 

architectural coatings) which are distributed across the region. Their emissions over a 

given area may be calculated using socioeconomic data. For 1997, reported data are 

used for point sources emitting more than 4 tons per year of any one of the criteria air 

contaminants (i.e., VOC, NOx, SOx, PM10). 

Area source emissions were jointly developed by the CARB and the District for a total 

of 350 categories. Several special studies were conducted to improve the area source 

inventory. Specific source categories such as gasoline dispensing, industrial coatings, 

consumer products, residential wood combustion, composting, fugitive dust, and 

ammonia sourced were updated. (See Appendix III of the 2003 AQMP.) 

 Mobile Sources 

Mobile sources consist of two subcategories: on-road and off-road sources. On-road 

vehicle emissions are calculated using socioeconomic data and transportation models 

provided by SCAG, spatial distribution data from Caltrans’ Direct Travel Impact Model 

(DTIM4), and EMFAC2002 inventories obtained from the CARB reflecting SCAG’s 
Chapter 3 Base Year and Future Emissions 

3 - 3 

revised baseline activity data (without 2001 RTP) and the activity data in 2001 RTP. 

The 1990 Census data combined with SCAG’s 1991 origin and destination survey data 

are used in SCAG’s 2001 RTP and in this AQMP. Major improvements made to 

EMFAC2002 include: 

1. Vehicle classes were extended to 13; 

2. Forecast capabilities were extended to 2040; 

3. Redefined four evaporative processes. Evaporative estimations were 

improved; 

4. Heavy-duty diesel truck emissions factors were updated. 

Figure 3-1 compares the on-road baseline emissions between EMFAC7G and 

EMFAC2002 used in the 1997 AQMP and 2003 AQMP respectively. It should be noted 

that the comparison reflects the change in methodology as well as adopted rules since 

the release of EMFAC7G. 

Emissions from off-road vehicle categories (e.g., trains, ships, construction equipment, 

utility engines) were developed primarily based on the estimated activity levels and 

emission factors. Special studies were conducted to improve the emission estimates for 

aircraft, marine vessels, and Metrolink train activity. (See Appendix III of 2003 AQMP.) 

More recent activity and population data were applied in the 2003 AQMP to calculate 

the emissions of lawn and garden equipment and locomotive categories. 

Gridded Emissions 

For air quality modeling purposes, the region is composed of the South Coast Air Basin, 

Coachella Valley, Antelope Valley, Ventura County (upwind area), and Mojave Desert. 

The modeling area is divided into a grid system composed of 5 km by 5 km grid cells 

defined by Universal Transverse Mercator (UTM) coordinates. Both stationary and 

mobile emissions are allocated to individual grid cells within this system. In general, the 

modeling emission data features episodic-day emissions. Seasonal variations in activity 

levels are taken into account in developing gridded stationary point and area source 

emissions. Variations in temperature, hours of operation, speed of motor vehicles, or 

other factors are considered in developing gridded motor vehicle emissions. Hence, 

“gridded” emissions data used for ozone modeling applications (Chapter 5) differ from 

the average annual day or planning inventory emission data in two respects: 1) the 

modeling region covers larger geographic areas than the Basin; and 2) emissions 

represent day-specific instead of average or seasonal conditions. In the 2003 AQMP, 

gridded inventories associated with selected ozone episodes have been prepared for air 

quality modeling analyses. In addition, gridded emissions for 1995 and 2006 were 

developed to calculate annual average PM10 concentrations. 
Final 2003 AQMP 

3 - 4 

FIGURE 3-1 

Comparison of Emissions Between EMFAC7G (1997 AQMP) 

and EMFAC2002 (2003 AQMP) 

* Year 2010 inventories incorporated rules adopted since the release of EMFAC7G

165

443

212

519

0

100

200

300

400

500

600

1997 2010

VOC

Tons/Day

365

606

434

761

0

100

200

300

400

500

600

700

800

900

1000

1997 2010

NOx

Tons/Day

14

20 21

19

0

5

10

15

20

25

1997 2010

PM10

Tons/Day

1809

3625

2048

5092

0

1000

2000

3000

4000

5000

6000

1997 2010

CO

Tons/Day

1997 AQMP 2003 AQMP *
Chapter 3 Base Year and Future Emissions 

3 - 5 

BASE YEAR EMISSIONS 

Reconstructed 1990 Emission Inventories 

The federal and state Clean Air Acts have specified the 1990 emission inventory as the 

baseline for measuring emission reduction progress. Therefore, inventories for year 

1990 have been revised since the adoption of the 1997 AQMP and the 1999 

Amendments to reflect improvements in emissions estimates and inventory 

methodology; this provides a consistent basis for emission trends analysis. Most 

noticeably, a significant change in methodology has been made to on-road, off-road and 

PM10 categories. For annual average day emissions (tons/day), year 1990 has the 

following inventory amounts. 

VOC: 1,780 NOx: 1,592 PM10: 339 

1997 Emission Inventory 

Table 3-1 shows the 1997 emissions inventory. Figure 3-2 characterizes relative 

contributions by stationary and mobile source categories. Stationary sources are 

subdivided into point (e.g., chemical manufacturing, petroleum production, and electric 

utilities) and area sources (e.g., architectural coatings, residential water heaters, and 

consumer products). Mobile sources consist of on-road (e.g., light-duty passenger cars) 

and off-road sources (e.g., trains and ships). 

Overall, total mobile source emissions account for 65 percent of the VOC and 89 percent 

of the NOx emissions for these two ozone-forming pollutants. The on-road mobile 

category alone contributes about 45 and 63 percent of the VOC and NOx emissions, 

respectively and approximately 76 percent of the CO. 

Within stationary sources, point sources contribute more NOx and SOx emissions than 

area sources. However, area sources play a major role in VOC emissions, emitting about 

three times more than point sources. Furthermore, area sources are the predominant 

source (82 percent) of directly emitted PM10 emissions due to inclusion of travel-related 

activities (road dust). 
Final 2003 AQMP 

3 - 6 

TABLE 3-1A 

Summary of Emissions By Major Source Category: 1997 Base Year 

Average Annual Day (tons/day1

) 

Source Category VOC NOx CO SOx PM10

Stationary Sources 

 Fuel Combustion 9 39 35 2 8 

 Waste Disposal 9 1 1 0 0 

 Cleaning and Surface Coatings 122 0 0 0 0 

 Petroleum Production and Marketing 63 0 5 4 1 

 Industrial Processes 20 0 4 0 6 

 Solvent Evaporation 

 Consumer Products 118 0 0 0 0 

 Architectural Coatings 51 0 0 0 0 

 Others 3 0 0 0 0 

 Misc. Processes * 21 29 106 0 224 

 RECLAIM Sources 0 62 0 18 0 

Total Stationary Sources 416 131 151 25 239 

Mobile Sources 

 On-Road Vehicles 519 761 5092 4 19 

 Off-Road Vehicles 237 312 1410 29 21 

Total Mobile Sources 756 1073 6502 33 40 

TOTAL 1172 1204 6653 58 279 

TABLE 3-1B 

Summary of Emissions By Major Source Category: 1997 Base Year 

Planning Inventory** (tons/day1

) 

SUMMER 

OZONE PRECURSORS

WINTER 

PRECURSORS

Source Category VOC NOx NOx CO 

Stationary Sources 

 Fuel Combustion 9 41 43 38 

 Waste Disposal 10 2 2 1 

 Cleaning and Surface Coatings 138 0 0 0 

 Petroleum Production and Marketing 63 1 1 5 

 Industrial Processes 24 0 0 4 

 Solvent Evaporation 

 Consumer Products 118 0 0 0 

 Architectural Coatings 60 0 0 0 

 Others 4 0 0 0 

 Misc. Processes 17 21 38 204 

 RECLAIM SOURCES 0 63 63 0 

Total Stationary Sources 443 128 147 252 

Mobile Sources 

 On-Road Vehicles 506 717 827 5027 

 Off-Road Vehicles 273 320 304 1182 

Total Mobile Sources 779 1037 1131 6209 

TOTAL 1222 1165 1278 6461 

* Travel related road dust included **Planning inventories are not used for PM10 analysis 1 Values are rounded to nearest integer 
Chapter 3 Base Year and Future Emissions 

3 - 7 

FIGURE 3-2 

Relative Contribution By Source Category to the 1997 Average Annual Inventory 

VOC Emissions: 1,172 Tons/Day

28%

7%

45%

20%

NOx Emissions: 1,204 Tons/Day

4%

63% 7%

26%

CO Emissions: 6,653 Tons/Day

2%

1%

76%

21%

SOx Emissions: 58 Tons/Day

2%

41%

8%

49%

Directly Emitted PM10 Emissions: 279

Tons/Day

53%

29%

4%

7%

7%

On-Road Off-Road Point Area Entrained Road Dust

Note: Consumer products and architectural coatings under the 

area source category represent 118 and 51 tons per day of VOC 

emissions, respectively. 
Final 2003 AQMP 

3 - 8 

In the mobile source category, emissions from on-road vehicles are much higher than 

those from off-road sources for all criteria pollutants except SOx. This can be explained 

by the fact that the sulfur content in fuels used for off-road vehicles is relatively higher 

than those for on-road vehicles. 

Figure 3-3 compares the 1997 inventory with the reconstructed 1990 inventories. As can 

be seen, emission reductions are shown for all pollutants due to adopted air regulations. 

*CO Emission values were divided by 10. 

FIGURE 3-3 

Comparison of Reconstructed 1990 Inventory and 1997 Inventory 

0

150

300

450

600

750

900

1050

1200

1350

1500

1650

1800

1950

1990 1997 1990 1997 1990 1997 1990 1997

VOC NOx CO PM10

Point Area On-Road Off-Road

1780

1172

1592

1204

1059

665

339 279
Chapter 3 Base Year and Future Emissions 

3 - 9 

FUTURE EMISSIONS 

Data Development 

The milestone years 2000, 2002, 2003, 2005, 2006, 2007, 2008, 2010 and 2020 are the 

target years for emissions rate-of-progress estimates under the federal Clean Air Act and 

the state Clean Air Act. Due to the adoption of the NOx and SOx RECLAIM program in 

October 1993, future emissions are divided into RECLAIM and non-RECLAIM 

emissions. Future NOx and SOx emissions from RECLAIM sources are estimated based 

on their initial allocations as specified by District Rule 2002 –Allocations for NOx and 

SOx. The forecasts for non-RECLAIM emissions were derived using: 1) emissions from 

the 1997 base year; 2) expected controls after implementation of District and CARB 

rules adopted by October 31, 2002; and 3) emissions growth in various source categories 

between the base and future years. Rules adopted after October 31, 2002 are treated as 

baseline adjustment measures for emissions reduction accounting purposes. A detailed 

description of the forecasting methodology is provided in Appendix III of the 2003 

AQMP. 

Demographic growth forecasts for various socioeconomic categories (e.g., population, 

housing, employment by industries), developed by SCAG for their 2001 RTP, were used 

to estimate future emissions. Industry growth factors for 2000, 2005, 2010, 2015 and 

2020 were provided by SCAG. Growth factors for other interim years were interpolated 

between key forecast years. Table 3-2 summarizes key socioeconomic parameters used 

in the 2003 AQMP for emissions inventory development. 

TABLE 3-2 

Baseline Socioeconomic Forecasts Used in 2003 AQMP 

Category 1997 2010 (% Growth) * 2020 (% Growth) * 

Population 

(Millions) 

14.3 16.5 (+15) 18.2 (+27) 

Housing Units 

(Millions) 

4.6 5.3 (+15) 5.9 (+18) 

Total Employment 

(Millions) 

6.3 7.8 (+24) 8.5 (+35) 

Daily VMT 

(Millions) 

296.8 387.4 (+31) 454.7 (+53) 

____________________________________________________________________________________________ 

* Relative to 1997 

Current forecasts indicate that this region will experience a population growth of 15 

percent by the year 2010 with a 31 percent increase in vehicle miles traveled (VMT). 
Final 2003 AQMP 

3 - 10 

The current projection for the year 2010 shows about 200,000 (1%) decrease in 

population, 200,000 (2.5%) decrease in total employment and 9.5 million mile (2.5%) 

increase in daily VMT forecast as compared to the projection from the 1997 AQMP. 

Summary of Baseline Emissions 

Emission data by source categories (point, area, on-road mobile and off-road mobile 

sources) and by pollutants are presented in Tables 3-3 through 3-5 for the years 2006, 

2010, and 2020. 

Without any additional controls, VOC, NOx, and CO emissions are expected to decrease 

due to existing regulations, such as the LEV and oxygenated fuel programs, and the 

RECLAIM program. Figure 3-4 illustrates the relative contribution to the 2010 

inventory by source category. A comparison between Figures 3-2 and 3-4 indicates that 

the on-road mobile category continues to be a major contributor to CO and NOx

emissions. However, due to the adopted LEV regulation, by 2010 on-road mobile 

accounts for about 34 percent of total VOC emissions compared to 45 percent in 1997. 

Meanwhile, area sources become the major contributor to VOC emissions from 28 

percent in 1997 to 36 percent in 2010. 
Chapter 3 Base Year and Future Emissions 

3 - 11 

TABLE 3-3A 

Summary of Emissions By Major Source Category: 2006 Base Year 

Average Annual Day (tons/day1

) 

Source Category VOC NOx CO SOx PM10

Stationary Sources 

 Fuel Combustion 10 29 41 2 8 

 Waste Disposal 10 2 1 0 0 

 Cleaning and Surface Coatings 54 0 0 0 0 

 Petroleum Production and Marketing 37 0 5 5 1 

 Industrial Processes 18 0 6 0 7 

 Solvent Evaporation 

 Consumer Products 104 0 0 0 0 

 Architectural Coatings 32 0 0 0 0 

 Others 3 0 0 0 0 

 Misc. Processes* 25 30 158 0 236 

 RECLAIM Sources 0 34 0 12 0 

Total Stationary Sources 293 95 211 19 252 

Mobile Sources 

 On-Road Vehicles 266 563 2602 5 20 

 Off-Road Vehicles 139 292 1160 36 21 

Total Mobile Sources 405 855 3762 41 41 

TOTAL 698 950 3973 60 293 

TABLE 3-3B 

Summary of Emissions By Major Source Category: 2006 Base Year 

Planning Inventory** (tons/day1

) 

SUMMER 

OZONE PRECURSORS

WINTER 

PRECURSORS

Source Category VOC NOx NOx CO

Stationary Sources 

 Fuel Combustion 10 30 31 44 

 Waste Disposal 10 2 2 1 

 Cleaning and Surface Coatings 64 0 0 0 

 Petroleum Production and Marketing 37 1 1 5 

 Industrial Processes 21 0 0 6 

 Solvent Evaporation 

 Consumer Products 104 0 0 0 

 Architectural Coatings 39 0 0 0 

 Others 3 0 0 0 

 Misc. Processes 19 21 42 320 

 RECLAIM Sources 0 36 36 0 

Total Stationary Sources 307 90 112 376 

Mobile Sources 

 On-Road Vehicles 261 536 605 2566 

 Off-Road Vehicles 162 303 283 965 

Total Mobile Sources 423 839 888 3531 

TOTAL 730 929 1000 3907

* Travel related road dust included **Planning inventories are not used for PM10 analysis 1 Values are rounded to nearest integer 
Final 2003 AQMP 

3 - 12 

TABLE 3-4A 

Summary of Emissions By Major Source Category: 2010 Base Year 

Average Annual Day (tons/day1

) 

Source Category VOC NOx CO SOx PM10

Stationary Sources 

 Fuel Combustion 10 25 43 2 9 

 Waste Disposal 10 2 1 0 0 

 Cleaning and Surface Coatings 61 0 0 0 0 

 Petroleum Production and Marketing 35 0 5 5 1 

 Industrial Processes 20 0 6 0 8 

 Solvent Evaporation 

 Consumer Products 108 0 0 0 0 

 Architectural Coatings 24 0 0 0 0 

 Others 3 0 0 0 0 

 Misc. Processes* 25 28 162 0 243 

 RECLAIM Sources 0 34 0 12 0 

Total Stationary Sources 296 89 217 19 261 

Mobile Sources 

 On-Road Vehicles 212 434 2048 2 21 

 Off-Road Vehicles 122 257 1094 39 19 

Total Mobile Sources 334 691 3142 41 40 

TOTAL 630 780 3359 60 301 

TABLE 3-4B 

Summary of Emissions By Major Source Category: 2010 Base Year 

Planning Inventory** (tons/day1

) 

SUMMER 

OZONE PRECURSORS

WINTER 

PRECURSORS

Source Category VOC NOx NOx CO 

Stationary Sources 

 Fuel Combustion 11 26 27 47 

 Waste Disposal 10 2 2 1 

 Cleaning and Surface Coatings 72 0 0 0 

 Petroleum Production and Marketing 36 1 1 5 

 Industrial Processes 23 0 0 6 

 Solvent Evaporation 

 Consumer Products 108 0 0 0 

 Architectural Coatings 28 0 0 0 

 Others 3 0 0 0 

 Misc. Processes 19 19 40 325 

 RECLAIM Sources 0 36 36 0 

Total Stationary Sources 310 84 106 384 

Mobile Sources 

 On-Road Vehicles 210 414 466 2019 

 Off-Road Vehicles 139 266 248 912 

Total Mobile Sources 349 680 714 2931 

TOTAL 659 764 820 3315 

* Travel related road dust included **Planning inventories are not used for PM10 analysis 1 Values are rounded to nearest integer 
Chapter 3 Base Year and Future Emissions 

3 - 13 

TABLE 3-5A 

Summary of Emissions By Major Source Category: 2020 Base Year 

Average Annual Day (tons/day1

) 

Source Category VOC NOx CO SOx PM10

Stationary Sources 

 Fuel Combustion 12 27 49 2 9 

 Waste Disposal 10 2 1 0 1 

 Cleaning and Surface Coatings 82 0 0 0 0 

 Petroleum Production and Marketing 37 0 5 5 1 

 Industrial Processes 26 0 9 0 9 

 Solvent Evaporation 

 Consumer Products 118 0 0 0 0 

 Architectural 27 0 0 0 0 

 Others 3 0 0 0 0 

 Misc. Processes* 25 27 170 0 256 

 RECLAIM Sources 0 34 0 12 0 

Total Stationary Sources 340 90 234 19 276 

Mobile Sources 

 On-Road Vehicles 130 206 1097 3 24 

 Off-Road Vehicles 114 241 1104 54 18 

Total Mobile Sources 244 447 2201 57 42 

TOTAL 584 537 2435 76 318 

TABLE 3-5B 

Summary of Emissions By Major Source Category: 2020 Base Year 

Planning Inventory** (tons/day1

) 

SUMMER 

OZONE PRECURSORS

WINTER 

PRECURSORS

Source Category VOC NOx NOx CO 

Stationary Sources 

 Fuel Combustion 12 29 30 53 

 Waste Disposal 10 2 2 1 

 Cleaning and Surface Coatings 99 0 0 0 

 Petroleum Production and Marketing 37 1 1 5 

 Industrial Processes 31 1 0 9 

 Solvent Evaporation 

 Consumer Products 118 0 0 0 

 Architectural 32 0 0 0 

 Others 3 0 0 0 

 Misc. Processes 19 18 39 340 

 RECLAIM Sources 0 36 36 0 

Total Stationary Sources 361 86 108 408 

Mobile Sources 

 On-Road Vehicles 131 196 220 1078 

 Off-Road Vehicles 125 250 232 928 

Total Mobile Sources 256 446 452 2006 

TOTAL 617 532 560 2414 

* Travel related road dust included **Planning inventories are not used for PM10 analysis 1 Values are rounded to nearest integer 
Final 2003 AQMP 

3 - 14 

FIGURE 3-4 

Relative Contribution By Source Category to the 2010 Average Annual Inventory 

VOC Emissions: 630 Tons/Day

36%

11%

34%

19%

NOx Emissions: 780 Tons/Day

5%

56% 6%

33%

CO Emissions: 3,359 Tons/Day

5%

1%

61%

33%

Directly Emitted PM10 Emissions: 

301 Tons/Day

49%

33%

5%

6%

7%

On-Road Off-Road Point Area Entrained Road Dust

Note: Consumer products and architectural coatings under the 

area source category represent 108 and 24 tons per day of VOC 

emissions, respectively. 

SOx Emissions: 60 Tons/Day

64%

4%

30%

2%
Chapter 3 Base Year and Future Emissions 

3 - 15 

Contributions by Responsible Agencies 

Figures 3-5A and 3-5B illustrate relative emission contributions by agency 

responsibility. Figure 3-5A shows that sources under CARB and U.S. EPA jurisdictions 

account for about 80% of ozone precursors (i.e., total of VOC and NOx) for year 2010. 

Figure 3-5B indicates that District and CARB are equally responsible for PM10 and 

PM2.5 emissions. Figures 3-5C and 3-5D illustrate source categories in VOC and NOx 

by responsible agencies. For VOC, light- & medium-duty vehicles and consumer 

products constitute the largest sources under CARB jurisdiction; while cleaning and 

surface coatings are the largest contributor (11 %) to emissions under the District’s 

jurisdiction. 

For NOx emissions, the transportation sector contributes to the largest portion of 

emissions under CARB and U.S. EPA jurisdictions; while RECLAIM facilities 

constitute the largest portion under the District jurisdiction. 
Final 2003 AQMP 

3 - 16 

FIGURE 3-5A – Relative Contribution by Agency to 2010 VOC and NOx 

Planning Inventory 

FIGURE 3-5B – Relative Contribution by Agency to PM2.5 and PM10 

Annual Average Inventory 

PM2.5

District

37%

EPA

20%

CARB

35%

N/A

8%

N/A: salt and soil/misc. ammonia PM10

District

51%

EPA

14%

CARB

28%

N/A

7%

N/A: salt and soil/misc. ammonia

2010 VOC Emissions = 659 Tons/Day

District

30%

CARB

66%

EPA

4%

2010 NOx Emissions = 764 Tons/Day

District

11%

CARB

56%

EPA

33%
Chapter 3 Base Year and Future Emissions 

3 - 17 

FIGURE 3-5C - 2010 VOC Emissions by Major Source Categories by Agency and 

Category

66% CARB

Consumer 

Products

16%

Light & Medium

 Duty Vehicles

27%

Off-Road 

Equipment

9%

Recreational 

Boats/Vehicles

6%

5%

Others

3%

HeavyDuty

Vehicles

4% EPA

Aircraft,

 Ships, Train

2%

Off-Road 

Equipment

& On-Road 

Vehicles

2%

30% District

Others

5%

Fuel Combustion

2%

Architectural 

Coatings

4% Industrial Processes

3%

Cleaning and 

Surface Coatings

11%

Petroleum 

Production

5%

(195 tons)

(32 tons)

(432 tons)
Final 2003 AQMP 

3 - 18 

FIGURE 3-5D - 2010 NOx Emissions by Major Source Categories by Agency and 

Category

56% CARB

Off-Road 

Equipment

5%

Others

1%

Recreational 

Boats/Vehicles

2%

27%

21%

Heavy-Duty

 Vehicles & Others

Light & Medium 

Duty Vehicles

33% EPA

Aircraft,

 Ships, Trains

 13%

Off-Road Equipment

& On-Road Vehicles

 20%

11% District

3%

Others

1%

RECLAIM

5%

Residential Fuel 

Combustion

2%

Non-Residential

Fuel Combustion

(424 tons) (254 tons)

(86 tons)
Chapter 3 Base Year and Future Emissions 

3 - 19 

The Impact of Growth 

To illustrate the impact of growth, year 2010 no-growth emissions were estimated by 

removing the growth factors from the 2010 baseline emissions. Figure 3-6 presents the 

comparison of the 2010 projected emissions with and without growth. 

FIGURE 3-6 

2010 Emissions Forecast With and Without Growth 

Annual Average Day 

630

525

780

659

336

278

60

54

301

256

0

100

200

300

400

500

600

700

800

G NG G NG G NG G NG G NG

Point Area Road Dust Off-Road On-Road

 VOC NOx CO** SOx PM10

*G = Emissions with growth; NG = Emissions without growth

** CO emissions are divided by 10