This document was prepared and published by the Memphis Metropolitan Planning Organization and is prepared in 

cooperation with financial assistance from all or several of the following public entities: the Federal Transit Administration,

the Federal Highway Administration, the Tennessee and Mississippi Department of Transportation, the Memphis Area 

Transit Authority, and the local governments in the MPO region. 

It is the policy of the Memphis Urban Area Metropolitan Planning Organization (MPO) not to discriminate on the basis of 

age, sex, race, color, national origin or disability in its hiring or employment practices, or in its admission to or operations 

of its program, services, or activities. All inquiries for Title VI and/or the American Disabilities Act, contact John Shaffer at 

901-576-7130 or John.Shaffer@memphistn.gov. 

2040 DESOTO COUNTY NON-ATTAINMENT AREA MOVES 

AIR QUALITY CONFORMITY DEMONSTRATION 

 

PREPARED BY: 

MEMPHIS URBAN AREA METROPOLITAN PLANNING ORGANIZATION 

 

 

 

IN COOPERATION WITH: 

DESOTO COUNTY 

ENVIRONMENTAL PROTECTION AGENCY 

FEDERAL HIGHWAY ADMINISTRATION 

FEDERAL TRANSIT ADMINISTRATION 

MISSISSIPPI DEPARTMENT OF ENVIRONMENTAL QUALITY 

MISSISSIPPI DEPARTMENT OF TRANSPORTATION 

SHELBY COUNTY 

SHELBY COUNTY HEALTH DEPARTMENT 

TENNESSEE DEPARTMENT OF ENVIRONMENT AND CONSERVATION 

TENNESSEE DEPARTMENT OF TRANSPORTATION 

MARCH 20, 2013 

MEMPHIS URBAN AREA METROPOLITAN PLANNING ORGANIZATION

TRANSPORTATION PLANNING SECTION
TABLE OF CONTENTS 

1 Introduction ............................................................................................................................................................................... 3

1.1 Latest Planning Assumptions ............................................................................................................................ 4

1.2 Latest Emissions Estimation Model................................................................................................................... 5

1.3 Interagency Consultation and Public Participation ........................................................................................... 5

1.4 Exempt Projects ................................................................................................................................................ 5

1.5 Conformity Test................................................................................................................................................. 7

2 Methodology ............................................................................................................................................................................. 7

2.1 MOVES............................................................................................................................................................... 8

2.2 Travel Demand Modeling.................................................................................................................................. 9

3 MOVES Runspec .................................................................................................................................................................... 12

3.1 Description ...................................................................................................................................................... 12

3.2 Scale ................................................................................................................................................................ 12

3.3 Time Spans...................................................................................................................................................... 12

3.4 Geographic Bounds......................................................................................................................................... 12

3.5 Vehicles/Equipment........................................................................................................................................ 12

3.6 Road Type........................................................................................................................................................ 12

3.7 Pollutants and Processes................................................................................................................................. 13

3.8 Miscellaneous Strategies................................................................................................................................. 13

3.9 Output............................................................................................................................................................. 13

4 County Data Manager ............................................................................................................................................................. 13

4.1 Meteorology Data Importer............................................................................................................................ 13

4.2 Source Type Population Importer................................................................................................................... 13

4.3 Age Distribution Importer............................................................................................................................... 14

4.4 Vehicle Type VMT and VMT Fractions............................................................................................................. 14

4.5 Average Speed Distribution Importer ............................................................................................................. 14

4.6 Road Type Distribution Importer .................................................................................................................... 15

4.7 Ramp Fraction Importer.................................................................................................................................. 15

4.8 Fuel Formulation and Fuel Supply Importer ................................................................................................... 15

4.9 Fueltype and Technologies Importer .............................................................................................................. 15

4.10 Inspection and Maintenance (I/M) Importer.................................................................................................. 15

5 Post-Processing of MOVES Output ........................................................................................................................................ 15

5.1 VMT and Source Type by County .................................................................................................................... 16

5.2 Source Type Population Fraction and VMT Fraction....................................................................................... 16

5.3 Hourly Distribution Fractions.......................................................................................................................... 16

5.4 Road Type Distribution Fractions.................................................................................................................... 16

5.5 Average Speed Distribution Fractions............................................................................................................. 16

5.6 Aggregation Tables.......................................................................................................................................... 16

6 Summary Results and Conclusions ........................................................................................................................................ 17
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LIST OF TABLES AND FIGURES 

Table 1 – MOVES Runspec Parameters ................................................................................................................................................ 8 

Table 2 – MOVES County Data Manager Parameters ........................................................................................................................... 8 

Figure 1 - MPO and Travel Demand Model Boundaries ....................................................................................................................... 10 

Table 3 – Annual VMT by Source Type by Year, DeSoto County Non-Attainment Area ...................................................................... 11 

Table 4 – Summary of Total Mobile Source Emissions ........................................................................................................................ 18 

Table 5 – Average NOx Emissions Rates by Source Type and Analysis Year ..................................................................................... 19 

Table 6 – Total NOx Emissions (grams) by Source Type and Analysis Year ....................................................................................... 19 

Table 7 – Average VOC Emissions Rates by Source Type and Analysis Year .................................................................................... 20 

Table 8 – Total VOC Emissions (grams) by Source Type and Analysis Year ...................................................................................... 20 

LIST OF EXHIBITS 

Exhibit 1 - Interagency Consultation Pre-Analysis Consensus Memorandum 

Exhibit 2 - 2011-2014 TIP and Memphis Urban Area 2040 LRTP Projects 
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1 Introduction 

As the number of vehicles on the nation’s roadways increased, air pollution from mobile sources was 

identified as an important national health concern. Recognizing this connection, the 1990 Clean Air Act 

Amendments (CAAAs) and the Mississippi Transportation Conformity Rules require transportation 

plans, programs (TIP), and projects to conform to the purpose of the Mississippi State Implementation 

Plan (SIP). Conformity to a SIP means that planned transportation activities will not produce new air 

quality violations, worsen existing violations, or delay timely attainment of the national ambient air 

quality standards (NAAQS). The Transportation Equity Act for the 21st Century (TEA-21) and its 

successor legislations, the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy 

for Users (SAFETEA-LU) and Moving Ahead for Progress in the 21st Century (MAP-21) reinforce the 

need for coordinated transportation and air quality planning through the metropolitan planning 

provisions. 

On May 21, 2012 the United States Environmental Protection Agency (EPA) designated the portion of 

DeSoto County, MS within the Memphis metropolitan area boundary as a marginal 8-hour ozone 

moderate non-attainment area (77 FR 30088). The 8-hour ozone area designation was effective on July 

20, 2012. The State of Mississippi appealed this finding, but a ruling posted in 78 FR 925 (January 7, 

2013) stated that appeal was formally denied by the EPA. The non-attainment portion of DeSoto 

County was classified as a marginal area, meaning they must reach attainment status within three years. 

In July 2012, EPA issued the companion guidance1 to the Conformity Rule that addresses ozone and air 

quality standards. The guidance further clarified how conformity determinations and the regional 

emissions analyses that support them are completed in existing and new non-attainment and 

maintenance areas. The guidance noted that states in a multi-state area have the option of submitting 

SIPs with budgets for just their own portion of the area that, when taken together, meet the applicable 

Clean Air Act requirement. Where states have done so and EPA has found such budgets adequate or 

approved, the MPO or MPOs in each state with such budgets can determine conformity completely 

independent of the other states. Furthermore, all affected agencies need to be included in the decisionmaking process for the area as required by §93.105 of the conformity rule. Shelby County, Tennessee 

and Crittenden County, Arkansas have budgets of their own. Since the portion of DeSoto County in 

non-attainment is classified as Marginal, it is not required to have a SIP budget. During the interagency 

consultation process, it was decided that DeSoto County would not be judged within the overall SIP 

budget established for Shelby County, but would instead be subject to an independent conformity 

demonstration using the baseline test. Therefore, this conformity determination is only for the DeSoto 

County portion of the 8-hour ozone non-attainment area. 

 

The purpose of this conformity analysis is to demonstrate that the partial DeSoto County nonattainment area supports the implementation of the financially constrained Direction 2040 Long 

Range Transportation Plan2

 (2040 LRTP) and the FY 2011-2014 Transportation Improvement 

Program (TIP) by contributing to improved air quality and will therefore not jeopardize DeSoto 

County’s attainment of the 2008 8-hour ozone NAAQS. The conformity determination has been 

performed according to procedures prescribed by the following federal, state and local regulations: 69 

FR 40004, 40 CFR Parts 51 and 93 (i.e. Transportation Conformity Rule Requirements); the Mississippi 

Transportation Conformity Rules; and Metropolitan Planning Organization (MPO) Planning 

 

1 Guidance for Transportation Conformity Implementation in Multi-Jurisdictional Nonattainment and Maintenance 

Areas, Transportation and Climate Division Office of Transportation and Air Quality, U.S. Environmental Protection 

Agency (EPA-420-B-12-046).

2 Please refer to 2040 LRTP, Chapter 8 for the detailed financial constraint aspect of the LRTP.
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Regulations (23 CFR 450) implementing MAP-21 Requirements. Results of this conformity 

determination are found in Table 3 of this report. For each transportation plan (2040 LRTP), program 

(2011-2014 TIP), and FHWA/FTA project to be found to conform, the MPO and DOT must 

demonstrate that the applicable criteria and procedures have been satisfied (section §93.109-a). The 

following criteria for non-attainment areas are found to be applicable and are described as: 

1) The TIP and LRTP must pass an emissions baseline test, comparing the conformity model 

years with a 2011 baseline value; 

2) The conformity determinations must be based upon the most recent planning assumptions; 

3) The conformity determinations must be based upon the latest emission estimation model 

available; 

4) MPOs and state departments of transportation must provide reasonable opportunity for 

consultation with state air agencies, local air quality and transportation agencies, DOT, and the 

EPA; and 

5) The conformity determination must comply with MAP-21 and MPO Planning Regulations. 

This report documents the process used by the Memphis MPO for the Conformity Determination for 

the DeSoto County portion of the Memphis Urban Area MPO 2040 LRTP and the 2011-2014 TIP. 

Since this area has only been recently designated as non-attainment, this conformity determination 

represents the first time an air quality analysis has been performed. EPA’s MOVES2010b model was 

used to derive emission factors as required by the EPA3

. The MOVES input files were created and 

modified as discussed in the interagency consultation process and laid out in the Pre-Analysis 

Consensus Memorandum (Exhibit 1). The emissions factors are based on a number of inputs including 

temperature, relative humidity, and presence of inspection and maintenance programs, vehicle source 

type mix, vehicle age distribution, temporal distributions, and other roadway attributes. Emissions 

estimates are the product of aggregating the results from the emission rate development with average 

daily vehicle miles traveled (VMT), source type populations, hourly distribution, road type distribution, 

and average speed distribution. 

The Memphis and Shelby County MPO Travel Demand Model was used to obtain VMT estimates. The 

Travel Demand Model was prepared with the conformity process in mind. For more information on 

the methodology and assumptions utilized in the development of the Travel Demand Model, please 

refer to the Model Documentation (LRTP Appendix G). 

1.1 Latest Planning Assumptions 

The Memphis and Shelby County MPO Travel Demand Model was developed with consultation and 

input from state and local transportation agencies and the USDOT. The 2040 LRTP provides the 

appropriate level of detail required by 40 CFR 93.106 of the conformity regulations. The highway 

projects in the 2040 LRTP are financially constrained for the entire plan and for each horizon year in 

terms of capital, operations and maintenance costs (See LRTP Chapter 8 – Implementation Plan). The 

conformity analysis is based on assumptions derived from estimates of current and future population, 

employment, travel, and congestion. As part of the 2040 LRTP conformity determination, past 

assumptions have been discussed with various local, state and federal agencies for their continued 

validity and updated whenever necessary. Detailed planning assumptions are presented in Section 2 of 

this report. 

 

3 Using MOVES to Prepare Emission Inventories in State Implementation Plans and Transportation Conformity: 

Technical Guidance for MOVES2010, 2010a, and 2010b, April 2012.
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1.2 Latest Emissions Estimation Model 

Mobile source emissions estimates for the ozone season (summer) were developed using EPA's Motor 

Vehicle Emission Simulator, MOVES2010b (June 2012), and travel estimates from the latest Memphis 

MPO Travel Demand Model. The Memphis MPO, Mississippi Department of Transportation 

(MDOT), and Tennessee Department of Transportation (TDOT) provided the most current data 

available for emissions calculations. The Federal Highway Administration (FHWA) and EPA's Air 

Planning Branch in Atlanta provided assistance and guidance as well. 

All of the projects in the 2011-2014 TIP are a subset of the 2040 LRTP and as such include a program 

of projects, which is consistent with the scope of the 2040 LRTP in design and implementation 

schedule. Detailed project lists are presented in Exhibit 2. 

1.3 Interagency Consultation and Public Participation 

Interagency consultation is the central coordinating mechanism for public agency involvement and 

input to the conformity determination. The conformity determination must be made according to 40 

CFR §93.105-(a)-(2) and (e) and the requirements of 23 CFR 450 (40 CFR §93.112, Criteria and 

Procedures). 

The Memphis MPO coordinated its activities for this conformity determination with numerous 

stakeholders and review agencies, including DeSoto County, Shelby County, Shelby County Health 

Department, Mississippi Department of Environmental Quality (MDEQ), Tennessee Department of 

Environment and Conservation (TDEC) Division of Air Pollution Control, MDOT, TDOT, FHWA, 

EPA, and other necessary agencies. The Memphis MPO has held teleconference calls and email 

correspondence to discuss the issues pertinent to the DeSoto County Conformity Demonstration (e.g. 

latest planning assumptions). Verbal and written comments from these calls and the meeting have been 

addressed (see Exhibit 1 - Interagency Consultation). To more fully communicate the assumptions 

being made as a part of the conformity analysis, a preconsensus plan was developed for the ozone 

analyses. This document, titled “2040 DeSoto County Non-Attainment Area MOVES Air Quality 

Analysis Pre-Analysis Consensus Memorandum,” was reviewed by the interagency consultation group 

and modified based on comments received. This document is included in Exhibit 1. 

The Memphis Urban Area MPO’s Public Participation Plan, adopted in 2007 and updated in 2011, 

specifies procedures to ensure public involvement in the planning process. All TPB and Engineering 

and Technical Committee (ETC), meetings are open to the public for comments on any item. The 

public was notified of the opportunities to comment on this conformity demonstration. All comments 

received from the public, committee members, and review agencies were addressed appropriately. 

Specific information related to the public participation process for development of the LRTP is 

provided in Chapter 2 and Appendix A of the LRTP document. 

1.4 Exempt Projects 

In evaluating the emissions impact of transportation activities in the conformity process, EPA 

regulations exempt certain projects included in a TIP or LRTP from analysis (see 40 CFR 93.126, 

93.127, and 93.128). This decision is based on the assumption that these projects do not directly impact 

transportation related air emissions or that they may not be able to be precisely analyzed. The 

regulations identified two general categories of projects in the Transportation Conformity Reference 

Guide: 1) those exempt from regional emissions analysis; and 2) other highway and transit projects. In 

the regional exemption category, the following projects are specifically named and are considered by 

this report to be classified as exempt: 
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 Intersection channelization projects; 

 Intersection signalization projects at individual intersections; 

 Interchange reconfiguration projects; 

 Changes in vertical or horizontal alignments; 

 Truck size and weight inspection stations; and 

 Bus terminals and transfer points. 

The “other highway and transit project” list is longer and includes four primary categories: 1) safety, 2) 

mass transit, 3) air quality, and 4) other specific activities which do not involve or lead directly to 

construction. 

 Safety 

o Railroad/highway crossing. 

o Hazard elimination program. 

o Safer non-Federal aid system roads. 

o Shoulder improvements. 

o Increasing sight distance. 

o Safety improvement program. 

o Traffic control devices and operating assistance other than signalization projects. 

o Railroad/highway crossing warning devices. 

o Guardrails, median barriers, crash cushions. 

o Pavement resurfacing and/or rehabilitation. 

o Pavement marking demonstration. 

o Emergency relief (23 U.S.C. §125). 

o Fencing. 

o Skid treatments. 

o Safety roadside rest areas. 

o Adding medians. 

o Truck climbing lanes outside the urbanized area. 

o Lighting improvements. 

o Widening narrow pavements or reconstructing bridges (no additional travel lanes). 

o Emergency truck pullovers. 

 Mass Transit 

o Operating assistance to transit agencies. 

o Purchase of support vehicles. 

o Rehabilitation of transit vehicles. 

o Purchase of office, shop, and operating equipment for existing facilities. 

o Purchase of operating equipment for vehicles (e.g., radios, fare boxes, lifts, etc.). 

o Construction or renovation of power, signal, and communications systems. 

o Construction of small passenger shelters and information kiosks. 

o Reconstruction or renovation of transit buildings and structures (e.g., rail or bus buildings, 

storage and maintenance facilities, stations, terminals, and ancillary structures). 

o Rehabilitation or reconstruction of track structures, track, and track bed in existing rights-ofway. 

o Purchase of new buses and rail cars to replace existing vehicles or for minor expansions of 

the fleet. 

o Construction of new bus or rail storage/maintenance facilities categorically excluded in 23 

CFR part 771. 
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 Air Quality 

o Continuation of ride-sharing and van-pooling promotion activities at current levels. 

o Bicycle and pedestrian facilities. 

 Other specific activities which do not involve or lead directly to construction, such as: 

o Planning and technical studies. 

o Grants for training and research programs. 

o Planning activities conducted pursuant to titles 23 and 49 U.S.C. 

o Federal aid systems revisions. 

o Engineering to assess social, economic, and environmental effects of the proposed action or 

alternatives to that action. 

o Noise attenuation. 

o Emergency or hardship advance land acquisitions (23 CFR §710.503). 

o Acquisition of scenic easements. 

o Plantings, landscaping, etc. 

o Sign removal. 

o Directional and informational signs. 

o Transportation enhancement activities (except rehabilitation and operation of historic 

transportation buildings, structures, or facilities). 

o Repair of damage caused by natural disasters, civil unrest, or terrorist acts, except projects 

involving substantial functional, locational or capacity changes. 

There are projects in the TIP and LRTP from each major category. 

1.5 Conformity Test 

The conformity tests specified in the federal transportation conformity rule are: (1) the emissions 

budget test, and (2) the emissions reduction test. For the emissions budget test, predicted emissions for 

the TIP/LRTP must be less than or equal to the motor vehicle emissions budget (MVEB) specified in 

the approved air quality implementation plan or the emissions budget found to be adequate for 

transportation conformity purposes. If there is no approved air quality plan for a pollutant for which 

the region is in non-attainment or no emission budget has been found to be adequate for transportation 

conformity purposes, the emissions reduction test applies. In the DeSoto County portion of the 

Memphis region, no MVEBs have been specified. As a result, the emissions reduction test has been 

used, with the year 2011 as the established baseline condition. 

2 Methodology 

The emissions inventory development and emissions projection discussion below identifies procedures 

used by the Memphis MPO to obtain emission rates for the DeSoto County portion of the Memphis 

non-attainment area. 

Table 1 summarizes the settings used in the MOVES run specification file. Table 2 lists the 

assumptions used in the MOVES County Data Manager. Further details on the use of MOVES are 

found in the following sections. 

 
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Table 1 – MOVES Runspec Parameters 

MOVES Runspec Parameter Settings 

MOVES2010b, Version 2012/04/10 

Scale County, Emission Rates 

Time Span Time aggregation = Hour 

1 month representing summer conditions (July) 

All hours of the day selected 

Weekdays only 

Geographic Bounds 1 custom domain – DeSoto County (partial) 

Vehicles/Equipment All valid source types, gasoline and diesel 

Road Type All road types including off-network 

Pollutants and Processes NOx, VOCs, total gaseous hydrocarbons, non-methane hydrocarbons, 

methane 

General Output Units = grams, joules, miles 

Output Emissions Time = hour, location = link, on-road emission rates by road type and 

source use type 

Advanced Performance None 

Table 2 – MOVES County Data Manager Parameters 

County Data 

Manager Input 

Data Source 

Meteorology Data Local data from Memphis airport (MEM). 

Source Type Population Default data was used for all years. 

Age Distribution Local and default. Local data from motor vehicle registration data (classes 

11, 21, and 31). Shelby County data (prepared by the University of 

Tennessee) applied for remaining vehicle source types. 

Vehicle Type VMT – 

HPMS Vehicle Type VMT 

Local data obtained from Memphis Travel Demand Model. 

Vehicle Type VMT – 

Monthly VMT Fraction 

Determined using EPA conversion tool for Annual Average Weekly VMT. 

Vehicle Type VMT – 

Daily VMT Fraction 

Determined using EPA conversion tool for Annual Average Weekly VMT. 

Vehicle Type VMT – 

Hourly VMT Fraction 

Local data obtained from Memphis Travel Demand Model. 

Average Speed Distribution Local data obtained from Memphis Travel Demand Model. 

Road Type Distribution Local data obtained from Memphis Travel Demand Model. 

Ramp Fraction Local data obtained from Memphis Travel Demand Model. 

Fuel Supply/Fuel Formulation Default 

Fueltype and Technologies Default 

I/M Programs No data entered. 

2.1 MOVES 

The Clean Air Act (CAA) requires US EPA to regularly update its mobile source emission models. US 

EPA continuously collects data and measures vehicle emissions to make sure the Agency has the best 

possible understanding of mobile source emissions. This assessment, in turn, informs the development 

of US EPA’s mobile source emission models. MOVES represents the Agency’s most up-to-date 

assessment of on-road mobile source emissions. MOVES also incorporates several changes to the US 

EPA’s approach to mobile source emission modeling based upon recommendations made to the 

Agency by the National Academy of Sciences. 
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The more detailed MOVES approach to modeling (when compared with the previous MOBILE 

model) allows US EPA to easily incorporate large amounts of in-use data from a wide variety of 

sources, such as data from vehicle inspection and maintenance (I/M) programs, remote sensing device 

(RSD) testing, certification testing, portable emission measurement systems (PEMS), etc. This approach 

also allows users to incorporate a variety of activity data to better estimate emission differences such as 

those resulting from changes to vehicle speed and acceleration patterns. MOVES has a graphical user 

interface which allows users to more easily set up and run the model. MOVES database-centered design 

provides users much greater flexibility regarding output choices. Unlike earlier models which provided 

emission factors in grams-per-mile in fixed output formats, MOVES output can be expressed as total 

mass (in tons, pounds, kilograms, or grams) or as emission factors (grams-per-mile and in some cases 

grams-per-vehicle). Output can be easily aggregated or disaggregated to examine emissions in a range of 

scales, from national emissions impacts down to the emissions impacts of individual transportation 

projects. The database-centered design also allows US EPA to update emissions data incorporated in 

MOVES more easily and will allow users to incorporate a much wider array of activity data to improve 

estimation of local emissions. For example, the improvements in MOVES will allow project-level PM2.5

emissions to be estimated. 

2.2 Travel Demand Modeling 

The Memphis Urban Area travel demand model is the most recent and approved regional travel 

demand model for the study area. The travel demand model boundary includes all of DeSoto County 

and Shelby County, as well as portions of Tipton, Fayette, and Marshall Counties. Figure 1 shows the 

Memphis Urban Area and the Travel Demand Model boundaries. Although model approval is a joint 

process between the MPO and the appropriate state review agencies, the Tennessee Department of 

Transportation (TDOT) is the primary agency responsible for approval of the travel demand model for 

use in developing the Long Range Transportation Plan (LRTP) and other planning activities of the 

Memphis MPO. The travel demand model used for the air quality conformity analysis was reviewed 

and approved for use for long range plan and air quality conformity analysis purposes. 

The Memphis Urban Area Travel Demand Model is a four step model. Trip generation, trip 

distribution, mode choice, and trip assignment components are included in the model. The base year 

of the travel demand model is 2004. Socioeconomic data was forecasted to the year 2040 as a part of 

the most recent LRTP. Appendix G of the 2040 LRTP contains the assumptions and methodology 

used to develop the travel demand model. 

Model Data Adjustments 

At the outset of this process, it was important to compare the information in the travel demand model 

to raw data obtained through traffic counts. The 2004 HPMS data was obtained from the Mississippi 

Department of Transportation (MDOT) for DeSoto County. The annual VMT shown in the HPMS 

data was compared to the total 2004 DeSoto County VMT shown in the travel demand model. This 

comparison yielded a HPMS/TDM ratio that was used to scale the VMT output from the model to 

more closely match documented conditions. This scaled VMT was used in the development of the 

HPMS vehicle type VMT. 

The adjusted annual vehicle miles traveled by MOVES vehicle source type for the study area are shown 

in Table 3. 
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Figure 1 – MPO and Travel Demand Model Boundaries
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Table 3 – Annual VMT by Source Type by Year, DeSoto County Non-Attainment Area 

Source Type Source 

Type 

ID 

Source Type VMT 

2004 2011 2015 2020 2030 2040

Motorcycle 11 3,549,769 4,366,366 5,417,479 6,291,863 8,219,229 10,364,090

Passenger Car 21 908,128,882 1,117,036,961 1,385,940,627 1,609,632,022 2,102,705,396 2,651,420,043

Passenger Truck 31 234,153,236 288,018,466 357,353,159 415,029,541 542,164,774 683,645,164

Light Commercial 

Truck 32 78,226,452 96,221,772 119,385,010 138,654,368 181,127,337 228,394,727

Intercity Bus 41 124,861 171,840 190,844 245,203 328,836 426,906

Transit Bus 42 71,569 88,674 93,892 116,185 151,105 196,116

School Bus 43 866,640 1,164,182 1,281,946 1,635,150 2,173,136 2,821,145

Refuse Truck 51 573,769 558,584 486,423 458,960 416,971 454,262

Single Unit Short-haul 

Truck 52 30,964,500 40,102,032 43,657,439 55,254,691 73,266,162 95,173,627

Single Unit Long-haul 

Truck 53 2,906,325 5,326,845 6,396,981 8,666,568 11,825,266 15,361,526

Motor Home 54 6,845,732 9,348,650 10,310,066 13,166,575 17,538,768 22,784,227

Combination Shorthaul Truck 61 26,430,150 27,981,581 30,036,023 43,009,553 52,470,839 65,597,197

Combination Longhaul Truck 62 25,930,003 34,234,946 39,625,175 61,304,525 76,979,080 96,236,222

Total 1,318,771,889 1,624,620,899 2,000,175,063 2,353,465,201 3,069,366,897 3,872,875,252

Pre-Processing 

Information was gathered from the travel demand model to generate the average speed distribution, 

road type distribution, hourly VMT distribution, HPMS vehicle type VMT, and ramp fraction. To 

streamline this process, a pre-processor was developed. The pre-processor performed many of the 

calculations and disaggregations needed to produce MOVES-ready spreadsheets for each input. 

MOVES spreadsheet templates for each input type were developed for the identified model years. 

Following this, a script was developed to pull the needed data from the model and perform any needed 

calculations. MOVES files generated through this exercise could then be applied directly in the County 

Data Manager. Additional information on the data sources used and needed data manipulation is 

contained in Sections 3 and 4. 

Post-Processing 

The analysis was performed using the emission rates method. As a result, post-processing of the data 

was required to arrive at the overall emissions output. To do this, the rate per distance and rate per 

vehicle output data were matched with the appropriate geographic area, analysis year, source types, 

pollutant types, road types, modeling hours, and speed classes and then aggregated with the 

corresponding source type population and vehicle miles traveled information. The resulting 

information was summarized by pollutant type for each full or partial county being analyzed to generate 

the overall emissions in tons per year. Sections 3 and 4 provide additional detail on the data sources 

gathered, modeling assumptions, and post-processing steps. 
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3 MOVES Runspec 

The MOVES2010b software was released by the Environmental Protection Agency in July 2012. This 

software uses a graphical user interface with a set of input categories. A Runspec can be developed that 

stores the input values for these categories. The values and information included in the Runspecs 

developed for this analysis are explained in more detail in the following sections. 

3.1 Description 

The information in this category is used to distinguish the individual Runspecs. For this analysis, the 

description is used to introduce the purpose for the analysis, the area being studied, and the year of 

analysis (i.e. 2004, 2011, 2015, 2020, 2030, and 2040). 

3.2 Scale 

This input window is used to detail the information needed for the domain/scale of the analysis as well 

as the calculation type. The county level was selected as the domain for this effort, since it is the 

appropriate level for use in SIP and regional conformity analysis. The emission rate method was 

chosen for the calculation type. This calculation type was chosen following a discussion with the 

involved review agencies to determine the most appropriate calculation method for this analysis. 

3.3 Time Spans 

The Time Spans input window has a variety of different timescale inputs that are used for 

understanding the level of temporal aggregation being used in the analysis. The time aggregation level 

was specified as hours, based on guidance from EPA/FHWA for the preferred aggregation level for 

conformity runs. Based on the interagency consultation process, the years 2004, 2011, 2015, 2020, 

2030, and 2040 were chosen for the analysis years. Each year was done within a different Runspec. 

Since the pollutant analysis being conducted is for the 8-hour ozone standard, July was chosen as the 

month to best represent summer conditions. Weekdays were selected as the representative day type 

since they are considered to be the worst-case type when compared with weekends. All hours of the 

day were included in the analysis to represent conditions over a full 24-hour period. 

3.4 Geographic Bounds 

This analysis consisted of a portion of DeSoto County. This input window also asks for the name of 

the domain input database. A total of six input databases were created during this process, reflecting 

the appropriate Runspec and input data for the analysis years 2004, 2011, 2015, 2020, 2030, and 2040. 

3.5 Vehicles/Equipment 

This input window allows the user to specify which fuel and vehicle types are present within the 

transportation network. There are thirteen different vehicle classes (referred to as source use types) and 

five different fuel types. This analysis considers the diesel and gas fuel types only. This was partly to 

reflect the lack of compressed natural gas and liquefied petroleum gas vehicles in the population, and 

also to allow for default fuel formulation and fuel supply information to be used in the study area. 

Within this, all possible vehicle and fuel types were considered. Diesel motorcycles, gas combination 

long-haul trucks, and gas intercity buses were removed since they are not represented in the vehicle 

population. 

3.6 Road Type 

The MOVES software incorporates five different roadway types: off-network, rural restricted access, 

rural unrestricted access, urban restricted access, and urban unrestricted access. Expressways and 
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freeways in the region are considered as restricted access facilities. For this analysis, all five vehicle 

types were considered. Off-network emissions are intended to account for vehicle starts and 

evaporative emissions for parked vehicles. While these emissions are not captured through the 

information in the regional travel demand models, default values can be used to assess their impacts. 

3.7 Pollutants and Processes 

This input window allows the user to specify different pollutants and processes that are desired for 

modeling. Since the purpose of this analysis is to assess emissions relating to the 8-hour ozone 

standard, the interagency consultation specified the inclusion of Oxides of Nitrogen (NOx), Volatile 

Organic Compounds (VOC), Non-Methane Hydrocarbons (NMHC), Total Gaseous Hydrocarbons (THC), and 

Methane (CH4).

3.8 Miscellaneous Strategies 

The MOVES software includes input windows where provisions can be specified for specific strategies 

such as on-road retrofit and rate of progress emissions. Since these strategies are not being applied in 

this location, no information was entered for this section. 

3.9 Output 

Output for the MOVES program is stored in a user-created database. Output databases were created 

for each of the 6 different Runspec conditions. As specified in the interagency consultation process, 

grams, joules, and miles were used as the units of measure in the output database. Based on the 

parameters already established in these Runspecs, the time measurement for this analysis was set as 

hourly, and the location was automatically set for the link level. To assist with post-processing 

aggregation, it was further requested that the source use type information be included with the output. 

4 County Data Manager 

Once all of the base parameters have been established for a given MOVES Runspec, the County Data 

Manager can be used to enter locally-specific data. Input provided in Excel spreadsheet format can be 

referenced using this tool, which converts the data to MySQL format and incorporates it into the 

MOVES analysis. For the DeSoto County portion of the non-attainment area, locally-specific data 

could consist of data used for the entire region, statewide, or county-level data. The following sections 

detail these input criteria, and the methodology and assumptions used to arrive at the information 

entered for each. 

4.1 Meteorology Data Importer 

Meteorological data for the analysis area was obtained from the Shelby County MOVES run conducted 

in late 2011. This data was collected at the Memphis International Airport and is assumed to be 

applicable for the DeSoto County non-attainment area as well as all analysis years. 

4.2 Source Type Population Importer 

This importer provides the user with the opportunity to enter vehicle population data sorted by the 13 

MOVES vehicle source types. The Pre-Analysis Consensus Memorandum indicated that DeSoto 

County data would be referenced where possible. When this data was analyzed, it was determined that 

inconsistencies in the vehicle type definitions were significant enough that the data set as a whole could 

not be used. Statewide data sources were also considered for use, particularly for trucks. However, 

these data are available only at the statewide level, not at the county level. As a result, default data was 

used as a starting point for all source types. The MOVES Technical Guidance offers guidance on how 

to leverage default population and VMT data alongside local VMT data to arrive at an estimate of the 
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local population. This methodology was applied for all analysis years. A growth rate was not applied, 

since growth is inherently built in through this methodology. 

4.3 Age Distribution Importer 

The Age Distribution Importer allows the user to provide vehicle age distribution data sorted by the 

MOVES vehicle source types. Vehicle age distribution is divided into 30 years based on vehicle model 

years. For each vehicle type, the sum of all age distributions will equal one. DeSoto County 

registration data was able to be used for motorcycles, passenger cars, and passenger trucks. For the 

remainder of source types, data was obtained from a study conducted by the University of Tennessee – 

Knoxville. This data was specific to Shelby County, and as such can be reasonably transferred to 

DeSoto County. 

4.4 Vehicle Type VMT and VMT Fractions 

This data importer asks the user for the VMT in the study area by HPMS vehicle class type, hourly 

VMT distributions, daily VMT distributions, and monthly VMT distributions. The HPMS vehicle class 

VMT is asked for an annual basis. To determine this information, data can be pulled from available 

travel demand models or from regional HPMS data. 

HPMS Vehicle Class VMT 

The HPMS vehicle class VMT was determined using the pre-processor developed within the travel 

demand model. The travel demand model classifies vehicles into automobiles, single unit trucks, and 

combination unit trucks. The three vehicle classes in the model were divided into the six HPMS 

vehicle class types through the pre-processor. Since the travel demand model produces daily weekday 

volumes, the EPA conversion tool was used to convert these daily VMT numbers to annual values. 

Daily VMT Fraction 

The EPA conversion tool for Annual Average Weekday Vehicles Miles Traveled was used to determine 

the daily VMT fraction for each analysis year. 

Monthly VMT Fraction 

The EPA conversion tool for Annual Average Weekday Vehicles Miles Traveled was used to determine 

the daily VMT fraction for each analysis year. Monthly VMT fractions are different on leap years 

(2004, 2020, and 2040) than on non-leap years (2011, 2015, and 2030). 

Hourly VMT Fraction 

The hourly VMT fraction was determined using the pre-processor developed within the travel demand 

model. To produce the information needed for the MOVES input file, the three vehicle classes in the 

model were expanded to the 13 MOVES vehicle source types. In addition, the four time of day periods 

in the model were expanded to represent each hour of the day. The default mix of off-network hourly 

distribution percentages was used for all vehicle classes. 

4.5 Average Speed Distribution Importer 

This importer gives the user the opportunity to enter locally specific average speed data, disaggregated 

by vehicle source type, road type, weekday/weekend, and hour of the day. The MOVES model uses 16 

speed bins, dividing speed distributions into a fraction of driving within each speed bin for each of the 

criteria listed previously. The average speed distribution was determined using the pre-processor 

developed within the travel demand model. The vehicle classes in the model were expanded to the 13 

MOVES vehicle source types, and the hourly distribution was expanded from the four time periods in 

the model to each hour of the day. 
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4.6 Road Type Distribution Importer 

The road type distribution importer can be used to incorporate locally-specific roadway distribution 

information. The average speed distribution was determined using the pre-processor developed within 

the travel demand model. The vehicle classes in the model were expanded to the 13 MOVES vehicle 

source types. 

4.7 Ramp Fraction Importer 

This importer allows the user to input the percentage of traffic on urban restricted and rural restricted 

roadways that is traveling on ramp facilities. The ramp fractions were determined using the preprocessor developed within the travel demand model. 

4.8 Fuel Formulation and Fuel Supply Importer 

The fuel formulation and fuel supply importers are used to input locally-specific fuel properties into the 

model. The pre-analysis consensus memorandum specified that default values would be used for this 

category. 

4.9 Fueltype and Technologies Importer 

This importer value considers the alternative vehicle fuels and technologies (AVFT). If no information 

is entered for AVFT, MOVES assumes a default mix of alternative fuels. The MOVES default mix 

assumes a small percentage of compressed natural gas (CNG) transit buses. Since there are no 

alternative fuel vehicles in the transit fleet for DeSoto County, the default value for this file was 

modified to reflect only diesel and gasoline fuel types. 

4.10 Inspection and Maintenance (I/M) Importer 

This importer would allow local inspection and maintenance data to be entered for the study area. The 

DeSoto County portion of the non-attainment area has no I/M program in place. When default data is 

exported for this, the file indicates there are no I/M programs in place for the area. Since this is an 

accurate representation of the I/M program in the area, no further data was entered. 

5 Post-Processing of MOVES Output 

Once the appropriate data was input into the MOVES Runspecs and the County Data Manager, the six 

scenarios were run using the MOVES program. The following MOVES output databases were 

produced: 

 DeSoto_2004 

 DeSoto_2011 

 DeSoto_2015 

 DeSoto_2020 

 DeSoto_2030 

 DeSoto_2040 

Since the emission rates method was used for this analysis, only two tables within each output database 

are used. The tables are called rateperdistance and ratepervehicle. Ultimately, information from both 

tables was used to determine overall emissions, aggregating the information for the running emissions 

(rateperdistance) and idling emissions (ratepervehicle). 
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The rateperdistance and ratepervehicle tables all represent scenarios for one geographic area (DeSoto 

County), one analysis year (2004, 2011, 2015, 2020, 2030, or 2040), one month (July), and one day type 

(weekdays). Results within the rateperdistance tables are disaggregated by hour of the day, pollutant 

type, process type, vehicle source type, roadway type, and speed category. Temperature and relative 

humidity data vary by the hour of the day. Results within the ratepervehicle tables are disaggregated by 

hour of the day, pollutant type, process type, and vehicle source type. Temperature data within these 

tables varies by the hour of the day. 

The final output desired for this analysis summarizes the total emissions by pollutant type for each 

analysis year and geographic area. As a result, the information contained in each scenario’s 

rateperdistance and ratepervehicle has to be matched with corresponding vehicle miles traveled (VMT) 

and source population data. To do this, a set of supporting tables were created that match these criteria 

with information contained in the rateperdistance and ratepervehicle tables such as vehicle source types, 

road types, speed categories, and hour of the day. The creation of those tables and the process used to 

calculate total emissions are detailed in the subsequent sections. 

5.1 VMT and Source Type by County 

This table displays the daily and annual VMTs and the source type population for all of the counties 

and analysis years in this effort. The daily VMTs were pulled for each area from the spreadsheets used 

to develop the HPMS vehicle type VMTs. Annual VMTs for each county were determined using the 

EPA converter spreadsheet. 

5.2 Source Type Population Fraction and VMT Fraction 

This table separates the vehicle population into the different source types, and then determines the 

fraction of the population represented in each type as well as the fraction of total VMT represented in 

each type. The source type populations were pulled from the adjusted default data used for the 

MOVES runs. Within the MOVES format, VMTs were gathered by the six HPMS vehicle classes 

rather than the 13 MOVES source types. As a result, a translation was needed to match the appropriate 

HPMS vehicle classes with the MOVES source types. One the two classification types were matched 

to one another, the source type fractions established based on the vehicle populations were used to 

factor VMTs of different source type classifications that fell within the same HPMS vehicle class. 

5.3 Hourly Distribution Fractions 

This table provides the hourly VMT fractions, separated by source type, road type, hour of the day, and 

state. Hourly distribution fractions were pulled from the table created for use in the MOVES program. 

5.4 Road Type Distribution Fractions 

This table provides the road type VMT fractions separated by vehicle source types. Road type fractions 

were pulled directly from the MOVES input file developed earlier. 

5.5 Average Speed Distribution Fractions 

This table provides the average speed fraction sorted by source type, road type, hour of the day, and 

speed class. This file is the same as the MOVES input file used earlier in this analysis. 

5.6 Aggregation Tables 

Once the supporting tables were created, the information within them needed to be combined in a way 

that matched the independent variables shown in the rateperdistance and ratepervehicle tables. Due to 
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the large number of records and computations required to perform this exercise, some sort of advanced 

database and/or scripting tool was necessary. Since the Memphis Urban Area Travel Demand Model is 

operated in the TransCAD platform, it was determined that a programming script developed and run in 

TransCAD would be an effective way to summarize this information. 

In an effort to create a step within this scripting process that could later be referenced and checked, 

two intermediate tables were developed. The tables developed were designated as the VMT Summary 

Table and the Source Type Population Summary Table. Each table’s intent and composition is 

described below, along with an example of the information produced within the tables. 

VMT Summary Table 

The VMT Summary Table contains many of the same independent variables found in the 

rateperdistance output tables; namely, state, analysis year, source type, road type, hour of the day, and 

average speed bin. This table further divides the information by the individual counties in the analysis. 

The intent of this table is to determine the proportion of daily and annual VMT for a given county and 

analysis year that is represented within each combination of vehicle source type, road type, hour of the 

day, and speed category. This table references the source type VMT fraction generated in the Source 

Type Population Fraction and VMT Fraction table, the road type VMT fraction generated in the Road 

Type Distribution table, the hour VMT fraction generated in the Hourly Distribution Fraction table, 

and the average speed fraction from the Average Speed Distribution Fraction table. These four values 

are multiplied together to determine an overall fraction, which is then multiplied by the corresponding 

daily and annual VMT established in the VMT and Source Type table. When the daily VMT 

proportions and annual VMT proportions are summed for a particular county and analysis year 

combination, they will equal the corresponding VMT values shown in the VMT and Source Type table. 

Source Type Population Summary Table 

The Source Type Population Summary Table contains many of the same independent variables found 

in the ratepervehicle output tables; namely, state, analysis year, source type, road type, and hour of the 

day. This table further divides the information by the individual counties in the analysis. The intent of 

this table is to determine the proportion of the source type population for a given county and analysis 

year that is represented within each combination of vehicle source type, road type, and hour of the day. 

This table references the source type population fraction generated in the Source Type Population and 

VMT Fraction table and the hour VMT fraction generated in the Hourly Distribution Fractions table. 

These two values are multiplied together to get an overall fraction, which is then multiplied by the 

corresponding source type population information found in the VMT and Source Type table. The 

population proportion should be equal to the corresponding source type population value shown in the 

VMT and Source Type table. 

6 Summary Results and Conclusions 

As mentioned in the previous section, a TransCAD script was developed to quickly match the 

information in the rateperdistance and ratepervehicle tables with corresponding VMT and source type 

population information. This script also summed the matched information by county, analysis year, 

and pollutant type to create the final output format needed for this process. Results from this script are 

produced in a form that is easily formatted to show the overall emissions information contained in the 

main body of this report. 
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Results from this analysis are summarized in Table 4. Additional detail on the average emission rates 

and total emissions has been provided in Tables 5 through 8. These tables break out emission rates 

and emissions for each analysis year by the 13 MOVES vehicle source types. Results from the 

rateperdistance analysis were averaged over all road types, hours of the day, and speed bins to obtain 

these values. Results from the ratepervehicle analysis were averaged over all hours of the day. 

Table 4 – Summary of Total Mobile Source Emissions 

Pollutant Emissions (tons/day) 

2011* 2015 2020 2030 2040 

Volatile Organic Compounds (VOC) 2.256 1.790 1.179 1.064 1.384 

Oxides of Nitrogen (NOx) 6.953 5.356 3.662 2.697 3.143 

 *Baseline analysis year 

2011 was identified through the interagency consultation process as the baseline year for this analysis. 

Based on the results from the MOVES analysis, each subsequent model year exhibits a reduction in 

emissions in both VOCs and NOx. 

The analysis indicates that the projected emissions levels based on projects contained in the Memphis 

Urban Area 2040 Long Range Transportation Plan (2040 LRTP) and FY 2011-2014 Transportation 

Improvement Program (TIP) meet the applicable conformity tests. It is the determination of this 

analysis that the FY 2011-2014 TIP and the 2040 LRTP conform under the 2008 8-hour ozone 

National Ambient Air Quality Standards. 
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Table 5 – Average NOx Emission Rates by Source Type and Analysis Year 

Source Type Source 

Type 

ID 

Analysis Year 

2004 2011 2015 2020 2030 2040

Average Emission Rate Per Distance Traveled

Motorcycle 11 0.99 0.67 0.59 0.54 0.52 0.51

Passenger Car 21 1.90 1.02 0.62 0.31 0.13 0.11

Passenger Truck 31 3.30 1.96 1.28 0.76 0.42 0.38

Light Commercial Truck 32 3.46 1.93 1.27 0.83 0.58 0.56

Intercity Bus 41 28.35 16.88 10.38 5.05 2.00 1.81

Transit Bus 42 27.49 15.11 8.78 4.14 1.78 1.67

School Bus 43 15.17 10.93 8.07 5.23 2.09 1.30

Refuse Truck 51 21.56 9.93 5.56 3.17 1.85 1.70

Single Unit Short-haul Truck 52 11.31 6.29 4.02 2.72 1.92 1.81

Single Unit Long-haul Truck 53 11.14 6.57 4.34 2.91 1.92 1.77

Motor Home 54 8.98 6.65 5.25 4.05 2.79 2.38

Combination Short-haul Truck 61 25.97 11.83 6.53 3.62 2.03 1.85

Combination Long-haul Truck 62 28.17 13.45 7.73 4.31 2.21 1.94

Average Emission Rate Per Vehicle

Motorcycle 11 0.00 0.00 0.00 0.00 0.00 0.00

Passenger Car 21 0.46 0.37 0.28 0.18 0.10 0.08

Passenger Truck 31 0.80 0.64 0.47 0.29 0.12 0.09

Light Commercial Truck 32 0.71 0.46 0.32 0.19 0.10 0.09

Intercity Bus 41 0.00 0.00 0.00 0.00 0.00 0.00

Transit Bus 42 0.01 0.01 0.01 0.01 0.00 0.00

School Bus 43 0.42 0.15 0.08 0.04 0.01 0.01

Refuse Truck 51 0.04 0.02 0.02 0.01 0.01 0.00

Single Unit Short-haul Truck 52 0.78 0.46 0.32 0.20 0.06 0.03

Single Unit Long-haul Truck 53 0.36 0.21 0.15 0.09 0.03 0.01

Motor Home 54 0.12 0.07 0.05 0.03 0.01 0.00

Combination Short-haul Truck 61 0.02 0.01 0.00 0.00 0.00 0.00

Combination Long-haul Truck 62 16.65 14.22 16.80 17.81 22.59 25.42

Table 6 – Total NOx Emissions (grams) by Source Type and Analysis Year 

Source Type Source 

Type 

ID 

Analysis Year 

2004 2011 2015 2020 2030 2040

Motorcycle 11 9,607 8,073 8,444 9,261 11,085 13,322

Passenger Car 21 3,649,503 2,502,888 2,001,985 1,162,272 724,622 779,818

Passenger Truck 31 1,704,909 1,264,167 1,056,109 693,223 507,901 590,677

Light Commercial Truck 32 490,893 337,035 293,522 211,795 212,397 278,278

Intercity Bus 41 6,843 6,023 4,111 2,218 1,277 1,532

Transit Bus 42 3,059 2,125 1,559 848 484 589

School Bus 43 22,192 21,782 18,203 14,520 7,917 6,714

Refuse Truck 51 25,135 10,837 5,358 2,865 1,561 1,637

Single Unit Short-haul Truck 52 578,272 429,755 313,753 272,283 278,187 356,255

Single Unit Long-haul Truck 53 52,384 58,617 48,673 45,042 44,839 56,077

Motor Home 54 117,047 118,236 105,361 103,509 100,713 116,520

Combination Short-haul Truck 61 1,368,611 639,336 384,719 291,033 205,787 245,154

Combination Long-haul Truck 62 1,476,650 908,646 617,034 513,662 349,505 404,732

Total NOx Emissions 9,505,103 6,307,521 4,858,832 3,322,532 2,446,275 2,851,305
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Table 7 – Average VOC Emission Rates by Source Type and Analysis Year 

Source Type Source 

Type 

ID 

Analysis Year 

2004 2011 2015 2020 2030 2040

Average Emission Rate Per Distance Traveled

Motorcycle 11 4.64 3.41 3.11 2.87 2.68 2.66

Passenger Car 21 1.55 0.63 0.36 0.20 0.12 0.11

Passenger Truck 31 2.47 1.06 0.63 0.33 0.18 0.17

Light Commercial Truck 32 1.56 0.64 0.38 0.23 0.16 0.15

Intercity Bus 41 1.56 1.29 0.91 0.44 0.18 0.16

Transit Bus 42 1.77 1.43 0.98 0.43 0.18 0.17

School Bus 43 2.70 1.58 1.10 0.72 0.33 0.22

Refuse Truck 51 1.54 0.94 0.59 0.39 0.28 0.26

Single Unit Short-haul Truck 52 2.32 1.38 1.00 0.76 0.61 0.59

Single Unit Long-haul Truck 53 2.43 1.51 1.12 0.84 0.66 0.63

Motor Home 54 4.22 2.87 2.38 1.91 1.49 1.40

Combination Short-haul Truck 61 1.59 0.96 0.56 0.32 0.19 0.17

Combination Long-haul Truck 62 1.52 0.99 0.60 0.36 0.20 0.18

Average Emission Rate Per Vehicle

Motorcycle 11 0.16 0.16 0.11 0.08 0.05 0.05

Passenger Car 21 0.84 0.61 0.48 0.36 0.28 0.27

Passenger Truck 31 1.25 0.97 0.71 0.46 0.27 0.24

Light Commercial Truck 32 0.87 0.57 0.41 0.28 0.18 0.17

Intercity Bus 41 0.00 0.00 0.00 0.00 0.00 0.00

Transit Bus 42 0.01 0.01 0.01 0.00 0.00 0.00

School Bus 43 0.40 0.16 0.08 0.04 0.02 0.01

Refuse Truck 51 0.05 0.04 0.03 0.02 0.01 0.01

Single Unit Short-haul Truck 52 0.65 0.43 0.31 0.21 0.10 0.07

Single Unit Long-haul Truck 53 0.54 0.36 0.27 0.18 0.09 0.07

Motor Home 54 0.34 0.29 0.23 0.16 0.07 0.06

Combination Short-haul Truck 61 0.03 0.01 0.00 0.00 0.00 0.00

Combination Long-haul Truck 62 5.99 3.38 3.17 2.81 3.17 3.50

Table 8 – Total VOC Emissions (grams) by Source Type and Analysis Year 

Source Type Source 

Type 

ID 

Analysis Year 

2004 2011 2015 2020 2030 2040

Motorcycle 11 26,572 23,385 27,655 27,510 36,617 50,740

Passenger Car 21 2,228,579 1,153,969 893,859 560,478 496,918 644,140

Passenger Truck 31 948,217 546,426 439,307 263,905 205,836 254,601

Light Commercial Truck 32 202,642 108,962 87,958 58,587 57,459 78,676

Intercity Bus 41 275 331 264 143 100 125

Transit Bus 42 160 160 139 71 45 57

School Bus 43 3,322 2,600 2,052 1,622 1,119 1,082

Refuse Truck 51 1,339 775 456 287 211 240

Single Unit Short-haul Truck 52 101,894 77,955 64,209 57,094 67,520 96,746

Single Unit Long-haul Truck 53 9,905 11,405 10,609 10,161 11,928 16,778

Motor Home 54 41,113 39,333 37,672 36,515 40,944 56,190

Combination Short-haul Truck 61 55,310 34,700 23,743 19,577 16,761 20,653

Combination Long-haul Truck 62 56,085 46,916 36,296 33,773 29,368 35,648

Total NOx Emissions 3,675,416 2,046,917 1,624,219 1,069,723 964,828 1,255,675