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APPENDIX F-3

PHILADELPHIA INTERNATIONAL AIRPORT 

INVENTORY AND METHODOLOGY

Bureau of Air Quality

Department of Environmental Protection
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I. Including Airport Emissions into the SIP – A Background 

A. A Brief Overview of the Philadelphia International Airport 

The Philadelphia International Airport (PHL) is an integral part of the economic engine 

that both drives growth and responds to growth in the 5-county Philadelphia region and 

beyond. The Federal Aviation Administration (FAA) has designated PHL as a large hub 

airport. Large hub airports are defined as commercial service airports that account for 

greater than one percent of total U.S. passenger enplanements.

PHL serves 26 scheduled passenger airlines, six cargo airlines, and general aviation. 

PHL serves as a domestic connecting hub and international gateway for US Airways and 

is a cargo hub for United Parcel Service. In 2002, PHL was ranked the 12th busiest 

airport in the United States in terms of aircraft operations. 

The airport has been incrementally expanded and improved since it opened in 1940. The 

most recent improvements include the construction of Runway 8-26 in 1999 and the new 

International Terminal A-West in 2003. FAA recently approved an extension of Runway

17-35 which is a project designed to immediately reduce current delays. Despite 

completing most of these projects designed to lessen delays, PHL was rated the fifth most 

delayed airport in the U.S. The FAA identified PHL as one of the airports that 

contributes significantly to delays throughout the national airport system. In 2000, the 

City of Philadelphia initiated a Master Plan Update to study the facility needs of the 

airport to meet future demand. The Master Plan Update projected that the duration of the 

average annual delay per operation at PHL would increase from its current level of nearly 

10 minutes to nearly 19 minutes with the current airport configuration. The total number 

of delayed operations would also increase. 

The City’s master plan consultants studied the delay times and developed possible 

remedies or alternatives. The Master Plan Update concluded that the current and 

projected delays needed to be reduced as soon as possible. The major long-term project 

proposed for reducing delay is known as the Capacity Enhancement Program (CEP). 

The CEP is proposed to be a significant redesign of the airport’s runway system, 

taxiways, and renewal of the terminals. The CEP alternatives under consideration strive 

to lower delay times, particularly during bad weather conditions. The primary way this 

will be accomplished would be to create more separation between runway configurations 

than exist now. This will enable multiple aircraft operations to occur simultaneously on 

at least two parallel runways during bad weather. The revised runway configuration 

would also be accompanied by a more efficient taxiway system. To construct the new 

airport layout would require a massive excavation and earth moving effort. The 

construction emissions as well as project related aircraft emissions may generate 

significant emissions of NOx and VOC. Other pollutants will probably not be significant 

enough to create a general conformity determination. 

The air quality effects of certain federally funded projects, that generate large amounts of 

direct or indirect emissions in non-attainment and maintenance areas, such as the CEP, 
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are required to be analyzed extensively. State and federal general conformity regulations 

require it. The primary concern being that these large projects may add enough 

emissions to cause or contribute to a violation of National Ambient Air Quality

Standards. An environmental impact statement (EIS) always accompanies a major FAA 

action such as the PHL CEP. Results from the EIS often serve as a basis for developing a 

general conformity determination. Specifically, general conformity is designed to ensure 

that a federal action will not produce emissions of a criteria pollutant that will: 

 Cause or contribute to new violations of the National Ambient Air Quality

Standards (NAAQS)

 Increase the frequency or severity of existing violations of the NAAQS, or

 Delay the timely attainment of any NAAQS or any required interim emissions 

reductions or milestones.

B. General Conformity

The Department of Environmental Protection adopted by reference in Pa Code, Title 25, 

Subchapter J the federal requirements contained in Determining Conformity of General 

Federal Actions to State or Federal Implementation Plans (40 CFR, Part 93, Subpart B). 

General conformity guides the Department in how to address emissions from all other 

federal actions not covered by 40 CFR, Part 93, Subpart B – Determining Conformity of 

General Federal Actions to State or Federal Implementation Plans. General conformity 

requires the federal agency taking an action, such as FAA approval of the CEP, to 

develop a general conformity determination for each applicable pollutant to determine 

that the total direct and indirect emissions in a non-attainment or maintenance area would 

not exceed specified rates outlined in the general conformity regulation. Since PHL is in 

the Philadelphia-Wilmington-Atlantic City Non-Attainment Area for ozone, general 

conformity requires that no federally funded project can emit a specific amount of ozone 

precursors, which includes oxides of nitrogen (NOx) and volatile organic compounds 

(VOC), during the calendar year that the project takes place. Currently, the total of direct 

and indirect emissions from federal actions may not exceed 100 tons per year of either 

NOx or VOC in the Philadelphia-Wilmington-Atlantic City Non-Attainment Area unless 

it is determined that the emissions are included in the area’s applicable SIP. 

PHL is also in Philadelphia-Wilmington, PA-NJ-DE PM2.5 nonattainment area which

includes Bucks, Chester, Delaware, Montgomery and Philadelphia counties in 

Pennsylvania, Burlington, Camden and Gloucester counties in New Jersey and New 

Castle County in Delaware. Precursors to the formation of fine particulate matter (PM2.5) 

are PM2.5, NOx, and SOx. Aircraft do not emit large amounts of SOx and they do not 

emit enough PM to trigger the need for a conformity determination. Although emissions 

of VOC do not contribute to the formation of PM2.5, VOC emissions are referenced 

because they are relevant to the airport’s general conformity determination.

In formulating its plans for attaining and maintaining the ambient standards, the 

Department needs to have a clear reference point in knowing how much potential 
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additional emissions would be generated from a large project like the CEP. When a 

project subject to general conformity exceeds the applicable emission, the indirect and 

direct emissions that are produced as a result of the project need to be entirely offset 

either through reducing the indirect or direct emissions, the development of additional 

mitigation measures in the non-attainment area, purchase of emission reduction credits, 

or a determination needs to be made that the emissions are included in the air quality

State Implementation Plan (SIP). A combination of the aforementioned emission 

reduction methods could also be fashioned.

C. Air Emissions from the CEP

An air quality analysis will be included in the EIS for the CEP. The air quality analysis is 

prepared in accordance with National Environmental Policy Act (NEPA) requirements. 

Part of the air quality analysis will include an emission inventory analysis of the relevant 

criteria pollutants.

For the general conformity regulation, emissions generated at PHL are estimated using 

two different scenarios. One scenario is the build scenario, which estimates the amount 

of emissions produced if the project is developed. The other scenario is the no-build 

scenario, which estimates the amount of emissions that would be produced if the airport 

continues on a business-as-usual course without building the CEP. As stated, the CEP 

will reduce delay. Reduced delay will greatly reduce emissions since aircraft taxi and 

queue times will diminish. Even though the new airport will accommodate more 

operations, the emissions generated after the airport is redesigned could be projected to 

be less than if the airport is operated without the improvements from the CEP in the 

future. In other words, the average delay times will be reduced such that they offset 

most, if not all, emissions from the extra operations accommodated by the proposed 

project. 

However, the CEP could generate a significant amount of emissions during construction. 

Increased emissions from less efficient aircraft operations efficiencies and the resulting 

increased delays probably would combine with construction emissions during years of 

construction. Aircraft operations during construction are anticipated to be less efficient 

primarily because fewer runways will be available at various points in time during the 

construction.

D. Cooperative Effort Launched to Include PHL Emissions in the SIP

Detailed inventories of the operations and emissions at PHL were developed. The 

Department worked closely with the City of Philadelphia, Division of Aviation, and their 

consultants (DMJM Aviation and Jacobs Consultancy, formerly known as Leigh-Fisher 

Associates) in a workgroup for several years in order to comprehensively describe and 

document the emissions from PHL in the SIP for the years 2002 and 2009. The airport 

workgroup strove to bring together all of the emissions from sources at PHL into a 
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detailed inventory of emissions. A detailed inventory will meet two goals: 1) an 

inventory will allow the Department to determine what emissions are included in the SIP 

in order for the airport to best develop a mitigation strategy for a project and 2) this will 

allow the airport to be eligible for Voluntary Airport Low Emissions (VALE) Funding. 

In addition, the FAA has undertaken an Environmental Impact Statement for the CEP, 

where the Department and the U.S. EPA have been actively engaged.

II. Emissions Inventory Development Methodology

A. Inventory Modeling

1. Modeling Project 

Emissions at PHL for 2002 and 2009 calendar year and ozone summer weekday were 

modeled using historic data and the most current forecast current data available. As 

stated, the department worked closely with the City of Philadelphia, the city’s Division of 

Aviation, and consultants to PHL to incorporate representative activity levels at PHL in 

all of the required emissions inventory modeling. 

2. Emission Dispersion Modeling System (EDMS) 

EDMS is the EPA-approved model that the Department used for developing emissions 

inventories for aircraft, ground support equipment, and auxiliary power units. The FAA 

and the U.S. Air Force developed EDMS. The most current version of EDMS available 

when the inventory was developed, EDMS 4.5, was used when the emissions inventory

was developed.

3. Mixing Height Used for Modeling PHL 

Mixing height is the altitude under which PM2.5 precursors mix to form PM2.5 in the lower 

atmosphere. A more accurate mixing height than the presumed default value in EDMS 

was used developing an inventory for PHL. Upper air meteorological data available from 

Sterling, Virginia in combination with surface data measurements taken at the PHL

generated 1-hr mixing heights in the meteorological preprocessor model PCRAMMET, 

EPA, PCRAMMET (software), Research Triangle Park, NC, June 1999. All mixing 

heights between 10 p.m. and 6 a.m. were not considered when generating these averages 

because a small percentage of flight operations occur between those hours. The average 

summer weekday mixing height was estimated to be 4,428 feet for PHL. The average 

annual daily mixing height was estimated to be 3,600 feet.

4. Estimating Emissions Not Related to Aircraft
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Other types of emissions sources exist at PHL such as highway motor vehicles, point, 

area, and nonroad sources. The Department developed an emissions inventory of these 

sources. In some cases, when emissions from an area were included in the regional SIP 

inventory, the Department separated the emissions and included them in the emissions 

estimates of the airport section. In other cases, for instance, motor vehicles, emissions on 

PHL property were not originally included in the regional SIP inventory and were added 

to the regional inventory as well as the airport inventory. 

B. Aircraft

Commercial aircraft operations were significant and were modeled by the EDMS 4.5 

model directly. Emissions from aircraft operations were the most significant source of 

emissions at the airport. Annual and ozone summer weekday emissions were modeled 

for both calendar years 2002 and 2009. Only annual emissions are considered for 

meeting general conformity requirements. At PHL, summer weekday emissions are 

typically greater than what would be experienced on a typical average annual day (annual 

emissions divided by 365 days). 

 

1. PHL Operations Data 

The Department obtained operational data for PHL that was more exact than any other 

airport that was modeled in Pennsylvania. Four sets of data were requested from the 

airport for this study, an average ozone season weekday and annual operations by aircraft 

type, or airframe for 2002 and 2009. 

The airport’s Noise and Operations Monitoring System (NOMS) provided the percent of 

total operations per aircraft type for both data sets. These percentages were applied to 

PHL aircraft activity data supplied by the FAA Air Traffic Control (FAA ATCT) tower at 

PHL. The aircraft activity data saved within the NOMS database consists of actual FAA 

radar supplied by the FAA ATCT to the airport as part of a Memorandum of Agreement 

(MOA). The MOA specifies that the airport collect aircraft radar data within 28 nautical 

miles radius of PHL up to 15,000 feet in altitude. All sensitive operations such as certain 

military operations are filtered and are not included in the inventory.

2. Average Ozone Season Week Day

The data consists of the daily average of all weekday (Monday through Friday) aircraft 

arrivals and departures on each runway at PHL for the months of July, August, and 

September 2002. A query of the NOMS database retrieved the aircraft operations that 

occurred for each of the three months for each aircraft type. The data was sorted by flight 

number in order to assign an aircraft type typical for that carrier and flight number. All 

operational unknowns were reconciled by comparing aircraft types common to a

particular airline operator and flight number. Total number of operations per aircraft type 

for each month was totaled. The total number of operations for each aircraft type was 

then computed as a percent of total operations for each aircraft type for the three-month 

time period. The percentages were multiplied by the number of aircraft operations 
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provide by the FAA ATCT to calculate the number of operations per aircraft type for an 

average ozone summer weekday. This number was divided by the number of weekdays 

in the ozone season to derive a summer ozone weekday average of operations per aircraft 

type. An ozone weekday average was not estimated for this plan since the state 

implementation plan for particulate matter examines annual emissions not daily

emissions.

3. Annual Operations 

This data consists of all aircraft arrivals and departures to and from each runway at PHL 

for calendar year 2002. A query of the NOMS database retrieved the aircraft operations 

described above. The data was sorted to address all unknown aircraft types and flight 

numbers in order to assign an aircraft type common for that airline and flight number. 

Types of aircraft were assigned to unknowns when possible. Total number of aircraft 

operations per aircraft type for each month was then totaled for all 12 months. The total 

number of operations per aircraft type was estimated as a percent of total operations for 

each aircraft type for the 12-month time period. These percentages were multiplied by

total annual aircraft operations provided by the FAA ATCT to calculate the number of 

annual operations per aircraft type.

4. Growing Operations To 2009 

In connection with the PHL Master Plan, forecasts of aviation activity and passenger 

enplanements through 2020 have been prepared and documented in the Philadelphia 

Master Plan Forecast Report. The forecasts were prepared by Leigh Fisher Associates, 

which is now known as Jacobs Consultancy, for the City of Philadelphia. The forecasts 

were prepared based on FAA Advisory Circular 150/5070-6B Airport Master Plans and 

are also consistent with the FAA Terminal Area Forecast. The forecasts were prepared 

using a standard methodology, summarized as follows:

 Analysis of historical growth trends, and in particular historical growth in relation 

to key factors such as economic activity and airline service developments. 

Statistical analysis was conducted to examine the historical growth trends and 

provide input to assumptions regarding future growth trends.

 Assumptions regarding future annual growth rates using professional judgment 

based on analyses of historical trends and reference to independent forecasts such 

as the Federal Aviation Administration (FAA) forecasts for the nation as a whole.

 Assumptions regarding the likely future trend in key ratios such as average 

aircraft size and boarding load factors, based on analyses of recent actual activity, 

information on airline fleet developments, and reference to independent forecasts 

such as the FAA forecast for the nation as a whole.

The forecasts are unconstrained demand forecasts; that is, not dependent on the assumed 

availability of airport capacity. These forecasts were submitted to FAA by the City of 
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Philadelphia for review and concurrence. These forecasts were considered reasonable by

FAA and approved for use in the Master Plan as well as for the CEP EIS.

The analysis yielded total number of operations expected in 2009 along with the 

percentage breakdown of operations per aircraft type. The total operations per aircraft 

type were allocated to the various engine configurations and specific aircraft types in the 

same proportion that were used in developing the 2002 inventory.

5. Aircraft Operations in EDMS 

An operation is considered either a takeoff or a landing. Operations for each aircraft type 

were divided by two to obtain landing-and-takeoff (LTO) cycles for each aircraft. EDMS 

requires that the number of LTO cycles per aircraft type are entered in order to calculate 

emissions. 

6. Engine Assignment 

EDMS assigns a default engine to each aircraft type. The default engine was used unless 

better data was known. In some cases, it was known that certain airlines operate aircraft 

with certain engine models that are not the default engines listed in EDMS. The actual 

engine was assigned to an aircraft type when available. Aircraft that used non-default 

engines and were similarly reflected in the EDMS modeling were the Airbus 319, Airbus 

320-211, Boeing 737-300, and the Boeing 757-200. See table titled “Comparison of 

Actual and EDMS Fleet Mixes and Engine Types 2002 Baseline Analysis” at the end of 

the appendix for further information. 

7. Suitable Aircraft Substitutions 

A few models of smaller aircraft were not included in EDMS. For those aircraft, a 

suitable substitute aircraft was used. A suitable substitute was usually an aircraft that 

used the exact or similar engine and the substitute aircraft had a similar weight to the 

actual aircraft. Aircraft that were not included in EDMS that had significant operations at 

PHL were the Lear 45, Lear 55, Lear 60, Mu-2 Marquise, and the B58 Baron. They were 

replaced by suitable substitutions Citation VII, IAI 1124 Westwind, Citation Sovereign, 

Jetstream 31, and Navajo. See table titled “EDMS Aircraft Recommended Substitutions 

PHL Master Plan SIP Assessment” at the end of this appendix for further information.

8. Ground Delay 

The method for developing the delay times per LTO at PHL was described in detail by

Jacobs Consultancy. In summary, the average taxi-out and average taxi-in times for each 

runway in the primary operating configurations, which are weather related, were taken 

from Appendix C of Airport Master Plan Technical Report 2004.17, Runway 17-35 

Extension, Capacity/Delay Simulation Analysis, August 27, 2004. A weighted average 

based on meteorological conditions and specific aircraft types that use the airport’s 

various runways during each operating configuration were developed. Two different 
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delay times were developed for 2002. One delay estimate represented larger aircraft that 

primarily use the larger runways and the other represented smaller aircraft, such as 

general aviation and air taxi aircraft, which primarily use the shorter runways. In 2009, it 

was forecasted that the extension to runway 17-35 would equalize the delay times of all 

aircraft at the airport.

The EDMS model places taxi time, idle time, and delay time in a single Time-in-Mode 

category, reflecting the operation of aircraft with engines at very low throttle settings. 

This Time-in-Mode is not intended to include delay where an aircraft is not running the 

main engines (e.g. waiting out a delay at the gate). Table 1 presents Taxi/Idle/Delay

Time-in-Mode used in the EDMS modeling that supported the SIP.

Table 1: Average Taxi/Idle/Delay Time-in-Mode per Landing and Take-Off Cycle at 

PHL

Year Smaller Aircraft 

Delay

Larger Aircraft 

Delay

2002 15.32 minutes 26.23 minutes

2009 34.00 minutes 34.00 minutes

C. Airport Ground Support Equipment

Airport ground support equipment (GSE) comprises pieces of equipment that service 

planes between operations. Some examples of GSE are: fuel trucks, baggage tractors, 

lavatory trucks, and cargo loaders. Aircraft GSE was assigned to the aircraft based on the 

size and functionality of the aircraft type, which can be thought of as a classification. 

The five different classifications of aircraft for describing the types of GSE associated 

with that classification are: narrow-body passenger, wide-body passenger, narrow-body

cargo, wide-body cargo and commuter aircraft. General aviation aircraft were assigned 

no GSE unless a default GSE assignment for a general aviation aircraft existed in EDMS. 

GSE assignment and the time of operation for individual pieces of equipment per LTO 

were the same as used in the Runway 17-35 Extension Project Environmental Impact 

Statement, developed during a GSE survey conducted at PHL. Although some GSE is 

powered by gasoline, EDMS does not output emissions based on the type of fuel used. 

Therefore, all GSE emissions were combined in the source classification code in the SIP 

that pertains to diesel fuel, 2270008005, since most GSE emissions are produced by 

diesel-powered equipment.

D. Auxiliary Power Units

An auxiliary power unit (APU) is a gas turbine engine used by many commercial jet 

aircraft to start the main jet engines, to provide electrical power, and to power the 
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onboard air conditioning (heating and cooling) system. The pilot of an arriving aircraft 

can shut down the main engines and operate an onboard APU to generate power and to 

condition the air. When parked at a gate, an aircraft can instead use 400 Hz electrical 

power from a mobile ground power unit or receive electrical power and pre-conditioned 

air from connections at the gate. Using ground-based power instead of an APU greatly 

reduces air emissions and energy consumption. 

An onsite Terminal Gate Survey was conducted on April 5 and April 6, 2004 at PHL to 

determine which passenger gates have 400 Hz electrical power. Every gate in Terminal 

A through F at PHL was visually inspected to determine whether the gates have 400 Hz 

power connection, a pre-conditioned air connection, or both. Approximately 83 percent 

of the gates at PHL had 400 Hz power in 2004. According to FAA guidance, aircraft that 

use gates that have 400 Hz power use their APU 7 minutes on average, which is required 

to be inputted into EDMS. The EDMS default time for an aircraft to use APU power at 

the gate is 26 minutes. The average time an APU was used at PHL in 2004 is described 

by the following calculation, (0.83 * 7 minutes) + (0.17 * 26 minutes) = 10.23 minutes. 

For all aircraft that have APU installed in the EDMS model, 10.23 minutes was assumed 

to be the average time that the APU was operated at PHL in 2004 and beyond. The APU 

usage was estimated to be 10.23 minutes per LTO in the 2009 inventory for all aircraft 

that use APUs.

The Terminal Gate Survey occurred after the 13 gates of Terminal A were brought into 

operation in 2003. All 13 gates at Terminal A have the capability of supplying 400 Hz 

power and pre-conditioned air. For the 2002 baseline emissions, the absence of Terminal 

A gates was taken into account. The average time an APU was used at PHL in 2002 is 

described by the following calculation, (0.79 * 7 minutes) + (0.21 * 26 minutes) = 10.99 

minutes. The APU usage was estimated to be 10.99 minutes per LTO in the 2002 

inventory for all aircraft that use APUs. 

The fuel used in APU was assumed to be jet fuel. APU emissions were classified in the 

SIP under their own source classification code, 2275070000 and the type of fuel is 

described as “other.” The Department assumed that the number of gates offering 

electrical power would not change until 2009. 

E. Highway Vehicles

Michael Baker Jr. Inc developed a motor vehicle emissions inventory at the airport. 

Highway vehicles emissions on the airport property are not included in the highway

vehicle inventory in Appendix E. Baker produced 2002 average annual estimates for the 

pollutants of hydrocarbons, CO, NOx, SO2, ammonia, and fine particulate for the 

emissions inventories for the airport section of the SIP.

1. Overview of Vehicular Traffic Included in Analysis 
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The on-road vehicle traffic associated with the airport was determined from the memos 

provided to Baker by DEP. Table 1 summarizes the two on-road categories and the 

associated vehicle types included in the emissions analysis.

Table 2: Summary of Vehicles Included in Analysis

Vehicles That Access 

Airport Terminals

Vehicles That Do Not 

Typically Leave the 

Airport

 Passenger Car (DropOff, Pick Up, 

Employee Parking, 

Passenger Parking)

 Courtesy Vehicles 

(Hotel Van, Park & 

Ride, Rental Car 

Bus, Shared Ride, 

Employee Parking 

Bus, Economy 

Parking Bus)

 Taxi

 Limousine

 Delivery / Service 

Vehicles

 Rental Cars

 Public 

Transportation (Bus, 

R-1)

 Rental Car Buses 

 Employee Buses

 Long Term Parking 

Buses

 Airport Service 

Vehicle Fleet

For each vehicle type, activity data was required to estimate emissions. The activity data 

was determined from provided memos, and where data was not available, assumptions 

were applied as documented in the emission calculation spreadsheets. Activity data 

included the following:

 Number of vehicles

 Distance of route through airport

 Travel distance within parking lots/garage

 Typical travel speeds

 Number of hot and cold starts 

 Idling at entry & exit of parking facilities

 Curbside dwell times

 Signal light delays (Number of signals and typical delay times)
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All provided activity data was for a 2002 average annual day. Average annual day

emissions were multiplied by 365 days to obtain average annual emissions. For emission 

calculations, the activity data was adjusted for growth to reflect a typical summer 

weekday in 2002 and 2009. The memo also provided an estimated growth rate of 43.9% 

to estimate 2009 on-road vehicular traffic for transportation modes that are expected to 

increase proportionate to passenger activity levels. Together the growth rate and seasonal 

adjustments result in an adjustment percentage of 57.2% for 2009.

The provided growth rates were determined from historical and projected growth in 

annual enplaned passengers at the airport. The growth percentages were applied directly

to passenger cars, taxis, limousines, rental cars, deliver vehicles, and airport service 

vehicle fleets. However, an alternative approach was applied to all airport-related buses. 

It was assumed that although passengers may grow by 43.9% between 2002 and 2009, 

buses grow at a slower pace since they may currently have some capacity to handle more 

passengers and associated business models do not increase activity proportionate to an 

increase in enplaned passengers. For the 2009 inventory, the average bus level was 

expected to be only 30% greater than the level in 2002. 

2. Emission Calculation Methodology

The emissions were calculated using EPA’s MOBILE6.2 emission model, which 

generates mobile source emission factors. The vehicle categories described above were 

mapped to the MOBILE6.2 vehicle classes. The 2002, 2008, and 2009 emission factors 

were calculated for each vehicle class for the following emission types:

 Exhaust running emissions

 Cold-start emissions

 Hot-start emissions

 Idling emissions

Exhaust running emission factors were calculated to account for emissions resulting from 

vehicle travel within the airport and within the parking lot/garage. The emission factors 

were calculated using assumed speeds of 20 mph for in-airport travel and 10 mph for 

travel within parking garages/lots. MOBILE6.2 produces exhaust emission factors in 

grams/mile. Total emissions were calculated for all the vehicle categories by multiplying 

the emission factors by vehicle miles of travel (number of vehicles * distance) based on 

the analysis assumptions.

Hot and cold-start emissions are calculated to account for emissions resulting from the 

total number of vehicle starts occurring within the airport vicinity. The factors were 

obtained through separate MOBILE6.2 runs. The output emission factors in grams/mile 

were converted to grams/start using MOBILE6.2 assumptions. The total start emissions 

were then calculated by multiplying the grams/start emissions by the total number of 

starts per day (number of vehicles * number of starts).
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Idling emissions were calculated to account for emissions resulting from vehicles idling 

at the airport. The factors, expressed in grams/hour were obtained by multiplying the 

running emission rates (grams/mile) for 2.5 mph by 2.5 mph as documented in EPA’s 

January 2002, Policy Guidance on the Use of MOBILE6 for SIP Development and 

Transportation Conformity. These factors were multiplied by the total number of vehicles 

per day and assumed idling times at garage or lot entry/exit points, curbside dwell, and 

traffic signals.

The total emissions resulting from each of these emission types were summed to get an

estimate of typical summer weekday emissions. Average weekday emissions were also 

estimated and multiplied by 365 days to obtain an annual estimate in emissions.

F. Nonroad Equipment

Emissions from nonroad equipment emissions, such as construction equipment, during 

2002 and 2009 from normal operations at PHL are included in the nonroad inventory for 

Philadelphia and Delaware Counties and were not included in this appendix. These ongoing construction emissions have been associated with capital budgets that ranged from 

$258 million in 2002 to as little as $56 million in 2005.

The Airport’s CEP project is expected to significantly ramp up the level of construction 

activities to greater than $5 billion of expenditures over a decade. This is also expected

to generate substantial construction emissions and result in a temporary increase in 

emissions from airfield delay. The construction emissions that will occur between 

January 1, 2010 and June 15, 2010 are forecast to be 37.3 tons of NOx.

G. Point Sources

There are 21 stationary sources of emissions at PHL. Many of these sources have the 

potential of using many different types of fuels. Philadelphia Air Management Services 

(AMS) provided to the Department 2002 emissions of NOx, VOC, CO, PM10, and SOx

produced by these sources while using specific fuels as shown by individual source 

classification codes (SCC). Most of these sources are boilers, generators and space 

heaters. The airport self reports emissions of these sources to Philadelphia Air 

Management Services. The Department applied growth factors to the 2002 emissions to 

obtain 2009 emission levels. Growth factors for point sources were obtained from the 

Environmental Protection Agency’s Economic Growth Analysis System. Point source 

emissions are included in the regional point source inventory, and also identified in this 

appendix.

Table 3: Point Sources at PHL

Source 

Number SCC Source Name

Growth 

Factors 

(2002-2009)

001 10300501 YORK-SHIPLEY BOILER #1 1.07306

001 10300602 YORK-SHIPLEY BOILER #1 1.01055
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Source 

Number SCC Source Name

Growth 

Factors 

(2002-2009)

002 10300501 YORK-SHIPLEY BOILER #2 1.07306

002 10300602 YORK-SHIPLEY BOILER #2 1.01055

003 10300501 YORK-SHIPLEY BOILER #3 1.07306

003 10300602 YORK-SHIPLEY BOILER #3 1.01055

004 10300501 KEWANEE BOILER #1 1.07306

004 10300602 KEWANEE BOILER #1 1.01055

005 10300501 KEWANEE BOILER #2 1.07306

005 10300602 KEWANEE BOILER #2 1.01055

006 10300501 WELL MCCLAIN BOILER #1 1.07306

006 10301002 WELL MCCLAIN BOILER #1 1.04706

006 10300601 WELL MCCLAIN BOILER #1 1.01055

007 10300501 WELL MCCLAIN BOILER #2 1.07306

007 10300601 WELL MCCLAIN BOILER #2 1.01055

008 10300501 WELL MCCLAIN BOILER #3 1.07306

008 10300601 WELL MCCLAIN BOILER #3 1.01055

009 10300501 MAINT. BLDG. BOILER #1 1.07306

009 10300601 MAINT. BLDG. BOILER #1 1.01055

010 10300501 MAINT. BLDG. BOILER #2 1.07306

010 10300601 MAINT. BLDG. BOILER #2 1.01055

011 10301002 AMERICAN STAND. BOILER #1 1.04706

011 10300602 AMERICAN STAND. BOILER #1 1.01055

012 20300102 EMERGENCY GENERATOR 1-GB 1.07306

013 20300102 EMERGENCY GENERATOR 2-GB 1.07306

014 20300102 CATERPILLAR GENERATOR 3 1.07306

015 20300102 OBRIEN EMERGENCY GEN. 1 1.07306

016 20300102 CATERPILLAR GEN. #4 1.07306

017 20300102 DETROIT DIESEL GEN. 1 1.07306

018 10500106 GENERAC GENERATOR 1 1.05459

019 10500106 MISCELLANEOUS HEATERS 1.05459

020 10500106 MISCELL. RESIDENTIAL HEAT 1.05459

021 10300501 CLEAVER BROOKS BOILER STP 1.07306

021 10300601 CLEAVER BROOKS BOILER STP 1.01055

H. Area Sources

Many different types of area sources exist at PHL, nevertheless, the total emissions from 

these sources are not very significant. Primary area sources include: fuel storage and 

transport, solvent use, waste management, painting operations, light industrial and 

commercial sources, and agriculture and miscellaneous area sources. Types of pollutants 

produced by area sources at the airport are primarily either VOC or particulate matter. 

Fuel storage and transport may seem to be a source that would lend itself to high 

emissions but, aviation fuel, like diesel fuel, is not very volatile and the amount of 

evaporative emissions produced is negligible. Most area source pollution is produced by 
15

solvent use or painting operations and is not estimated. These emissions are captured in 

our regional area source inventory. Area source emissions are included in the regional 

area source inventory and not included in this appendix.

I. Capacity Enhancement Program Emissions

The Department included emissions from the CEP. Appendix F-4, PHL Capacity 

Enhancement Program Construction Period Air Emissions Inventory, examines the CEP 

project pertaining to the air emissions that will be generated by the project. Appendix F4 explains the two design alternatives considered for the CEP, the construction process, 

air inventory methodology, emissions inventory results, and a summary of the emissions 

for various pollutants. The CEP’s emissions of NOx and VOC may exceed the de

mimimis threshold as defined by General Conformity in 40 CFR §93.153 for a moderate 

nonattainment area inside an ozone transport region, like the Philadelphia area. 

As stated in Section III of the Attainment Demonstration and Base Year Inventory, 

Pennsylvania proposes to establish budgets for VOC emissions that are forecasted to be 

created by the CEP in order to ensure that the VOC emissions of the CEP do not impede 

clean air goals established in the SIP. The highest amount of VOC emissions associated

with each build alternative for any year of construction, 254 tons, is used as the budget. 

Total VOC emissions of 254 tons appear in Table III-2 in the State Implementation Plan 

Revision: Attainment Demonstration and Base Year Plan. The emissions are comprised 

of 248 tons of VOC produced from increased aircraft delay and 5.5 tons produced by 

construction equipment used on the project. The Department concluded that since the 

VOC emissions used in the modeling of attainment for the fine particulate matter 

standard are 10,000 tons greater than the actual VOC emissions included in the SIP the 

Department can include the VOC emissions from the CEP and still satisfy the 

requirements of general conformity that are outlined in Section A of this appendix.

Once EPA approves this state implementation plan revision, a general conformity budget 

will be established for the CEP project in the Attainment Demonstration and Base Year 

Inventory.

III. Emissions Summary

Table 4: 2002 Annual PHL Emissions of PM2.5 Precursors (tons) 

Sources of Emissions NOx VOC CO PM10 PM2.5 SOx

Aircraft 1880.68 310.70 2123.61 10.60 10.60 165.28

Ground Support Equipment 242.72 148.21 3823.76 9.25 8.29 24.18

Auxiliary Power Units 28.87 3.05 44.29 0.00 0.00 4.18

Construction Equipment --- --- --- --- --- ---

Airport Motor Vehicles 251.56 43.70 592.38 9.50 9.50 7.45

Area Sources --- --- --- --- --- ---

Point Sources 13.15 0.35 4.08 0.43 --- 7.48
16

Table 5: 2009 Annual PHL Emissions of PM2.5 Precursors (tons) 

 

IV. Northeast Philadelphia Airport

Methodology and Emissions Summary

The City of Philadelphia also manages the Northeast Philadelphia Airport (PNE). PNE 

emissions are also included in the SIP. PNE is the city’s general aviation reliever and is 

located approximately 15 miles north of PHL. 

Total annual aircraft operations were based on the operations contained in the FAAs 

Terminal Area Forecast (TAF). The TAF is the official forecast of aviation activity at 

FAA facilities. The TAF includes historic and projected aircraft operations at PNE. The 

forecast is an unconstrained demand forecast. It is not dependent on the assumed 

availability of airport capacity. Types of aircraft using PNE in 2004 were predicted using 

the City of Philadelphia NOMS. The percentage that certain aircraft type used the airport 

in 2004 was carried directly forward to 2009. Total operations by aircraft type were 

apportioned to the total operations in 2002 and 2009 as predicted by the TAF. Operations 

data was inputted into EDMS similarly as described above for PHL.

Table 6: 2002 Annual PNE Emissions of PM2.5 Precursors (tons)

Sources of Emissions NOx VOC CO PM10 PM2.5 SOx

Aircraft 41.76 68.05 1637.95 9.25 8.92 24.18

Ground Support Equipment 24.60 20.04 518.80 0.65 0.63 1.86

Auxiliary Power Units 1.30 0.02 0.26 0.00 0.00 0.13

Table 7: 2009 Annual PNE Emissions of PM2.5 Precursors (tons)

Sources of Emissions NOx VOC CO PM10 PM2.5 SOx

Aircraft 2662.28 534.90 3785.90 16.22 16.22 250.72

Ground Support Equipment 245.82 189.97 4976.11 16.23 15.69 33.76

Auxiliary Power Units 36.78 3.28 45.30 0.00 0.00 4.99

Construction Equipment --- --- --- --- --- ---

Airport Motor Vehicles 169.41 21.74 396.76 4.03 4.03 1.68

Area Sources --- --- --- --- --- ---

Point Sources 13.76 0.36 4.22 0.45 --- 8.02

Capacity Enhancement Program --- 254.00 --- --- --- ---
17

Sources of Emissions NOx VOC CO PM10 PM2.5 SOx

Aircraft 32.96 55.98 1337.37 16.23 15.68 33.77

Ground Support Equipment 15.62 14.75 381.59 0.63 0.61 1.45

Auxiliary Power Units 0.98 0.02 0.20 0.00 0.00 0.10

 

Aircraft Engine Total

% of Total 

Operations EDMS Engine Type NOx Comments

CFM56-5A5 501 2.5%

CFM56-5B6/P 15,810 78.2%

V2522-A5 2,767 13.7%

V2524-A5 1,139 5.6%

CFM56-5A1 (A320-211) 445 4.6%

CFM56-5A3 (A320-212) 661 6.8%

CFM56-5B4/P (A320-214) 6,170 63.8%

V2500-A1 (A320-231) 839 8.7%

V2527-A5 (A320-232) 1,554 16.1%

CFM56-3B1 16,201 57.6%

CFM56-3B2 10,142 36.1%

CFM56-3C1 1,773 6.3%

CFM56-3B2 11,571 100.0%

JT8D-15 62 0.4%

PW2037 1,965 13.7%

PW2040 951 6.6%

RB211-535E4 10,445 72.7%

RB211-535E4-B 940 6.5%

Total: 83,935

Note: Grand Total does not match the grand total in the "AircraftDist.pivot" tab because some airlines' aircraft did not appear in jpfleets

RB211-535E4

CFM56-3B-2

CFM56-3B-2

CFM56-5A1

PW2037's are also included in the EDMS 

fleet mix. Confirm that LTO's assigned to 

each engine type reflect the actual 

distribution of operations.

GOOD

CFM56-3B1's represent the majority of B737-300 operations in 2002, but are not 

reflected in the EDMS fleet mix.

A majority of the A320 aircraft types (-212, -

214, -231, -232) and engine types operating 

at PHL in 2002 are not reflected in the 

EDMS fleet mix.

Philadelphia International Airport

2002 BASELINE ANALYSIS

COMPARISON OF ACTUAL AND EDMS FLEET MIXES AND ENGINE TYPES

V2522-A5

A majority of the A319 engine types 

operating at PHL in 2002 are not reflected in 

the EDMS fleet mix.

A319 0.535

B-757-200

B-737-400

B-737-300

A320-211

0.596

0.260

0.515

0.240
18

Aircraft Actual Engine Type

EDMS Engine 

Type (1) Aircraft Actual Engine Type

EDMS Engine 

Type

Lear 45 Honeywell TFE731-20-AR TFE731-3 Citation VII Honeywell TFE731-4R-2S TFE731-3

Lear 55 Honeywell TFE731-3A-2B TFE731-3 IAI 1124 Westwind Honeywell TFE731-1100G TFE731-3

Citation Sovereign Pratt & Whitney PW306C PW308C

Falcon 20 Honeywell TFE731-5BR-2AC TFE731-3

Cessna 441 Conquest2 Honeywell TPE331-8-410S/402S TPE331-8

Jetstream 31 Honeywell TPE331-10 TPE331-10

Navajo Lycoming TIO-540-A TIO-540-J2B2

Cessna T337 Continental IO-360-C IO-360-B

Notes:

(1) EDMS engine type for actual fleet mix not present in EDMS model are derived from "Appendix F: Engine Mappings" of the SAGE Version 1.5 Technical Manual

(2) EDMS engine types for aircraft in the EDMS model are taken directly from EDMS model.

Sources:

 airliners.net / The International Directory of Civil Aircraft

 SAGE Version 1.5 Technical Manual: Appendix F

 Bombardier Learjet 45 General Specifications

 Bombardier Learjet 60XR General Specifications

 Cessna Citation Sovereign General Specifications

 Dassault Falcon 2000EX Specifications

B58 Baron Teledyne Continental IO-550C ?

MU-2 Marquise Honeywell TPE331-10-501M

Lear 60 Pratt & Whitney PW305A (4) ?

TPE331-10

Actual Fleet Mix EDMS Substitution

PHL MASTER PLAN SIP ASSESSMENT

EDMS AIRCRAFT RECOMMENDED SUBSTITUTIONS