Technical Support Document (TSD) for the 

Redesignation Request and Maintenance Plan 

For the Pennsylvania Portion of the 

Philadelphia-Wilmington, PA-NJ-DE 

2006 PM2 s Nonattainment Area 

Submitted by 

Pennsylvania Department of Environmental Protection 

TSD Prepared December 2014 by 

Jessica L. Fry 

Office of Air Monitoring and Analysis, 3AP40 

U.S. Environmental Protection Agency, Region 3 

1650 Arch Street 

Philadelphia, Pennsylvania 19103 

Reviewed by Alice . Chow, Associate Director 

Office of Air Monitoring and Analysis (3AP40) 
I. Introduction 

The purpose of this document is to provide a technical summary of the Office of Air Monitoring 

and Analysis (OAMA) review of the emissions inventories submitted with the Redesignation 

Request and Maintenance Plan for the Pennsylvania portion ofthe Philadelphia-Wilmington, 

PA-NJ-DE 2006 PM2.s Nonattainment Area (NAA) by the Pennsylvania Department of 

Environmental Protection (P ADEP). The Pennsylvania portion of the NAA consists of Bucks, 

Chester, Delaware, Montgomery, and Philadelphia counties. This review does not determine the 

approvability of the redesignation request or maintenance plan. Emissions inventories in a 

redesignation request are used to show permanent and enforceable emission reductions between 

the year the area was designated as a nonattainment area and the year the area came into 

attainment. In a maintenance plan, the emissions inventories are used to reflect the emissions 

during the time the area came into attainment and are then projected to show that the area will 

remain in attainment. Any questions pertaining to this technical summary should be directed to 

Alice H. Chow, Associate Director, Office of Air Monitoring and Analysis, at 215-814~2144 or 

via email at chow.alice@epa.gov. 

II. Emissions Inventories for Redesignation Request 

2002 Base Year Inventory 

In a redesignation request, emissions inventories are used to support the States claim that 

the area has permanent and enforceable emissions reductions. In order to do this, the state 

should estimate the percent reduction achieved from federal and state control measures (typically 

from the year that was used to determine the design value for designation and classification); this 

is usually termed as the nonattainment year inventory. The 2002 nonattainment year inventory 

contains primary PM2.s emissions (including condensibles), S02, NOx, NH3, and VOC. PADEP 

submitted their 2002 Base Year Inventory to EPA as a State Implementation Plan (SIP) revision. 

The inventory was approved by EPA and the rule became effective August 28, 2012 (77 FR 

51930). Documentation for this inventory can be found in the Federal Registrar Notice. 

III. Emissions Inventories for Maintenance Plan 

2007 Attainment Year Inventory and Maintenance Plan Base Year Inventory 

Under section 172(c)(3) states are required to submit a comprehensive, accurate, current 

accounting of actual emissions from all sources (point, nonpoint, nomoad, and omoad) in the 

nonattainment area. This inventory contains primary PM2.s emissions (including condensibles), 

S02, NOx, VOC, and NHJ. In a Maintenance Plan, states are required to submit an inventory used 

for the year of attainment, which is called the attainment year inventory and can also be referred 

to as the maintenance plan base year inventory. This inventory is used as the basis for the 

projected inventories that are used to show the area will remain in attainment. The attainment 

year inventory contains primary P~v'12 s emissions (including condensibles), S02, !'-~Ox, l'-~H3, and 

VOC. PADEP is using emissions from 2007 as a surrogate attainment year inventory. A 
comparison of the 2007 and 2008 emissions was submitted to show that this is a conservative 

approach. This section will discuss the 2007 attainment year inventory that was used in the 

Pennsylvania portion of the Philadelphia-Wilmington, P A-NJ -DE Redesignation Request and 

Maintenance Plan submitted by PADEP in order to fulfill the 172(c)(3) and attainment year 

emissions inventory requirements. 

For the 2007 attainment year inventory for point, nonpoint, and nonroad categories, 

PADEP submitted the 2007 Version 3 Emissions Inventory developed through the Mid-Atlantic 

Regional Air Management Association (MARAMA) regional planning process. A 

comprehensive county level inventory for the Philadelphia nonattainment area (NAA) was 

developed by PADEP in coordination with MARAMA, New Jersey Department of 

Environmental Protection (NJDEP), and Delaware Department ofNatural Resources and 

Environmental Control (DNREC). Documentation of the development ofthe inventory can be 

found in Technical Support Document for the Development of the 2007 Emission Inventory for 

the Regional Air Quality Modeling in the Northeast I Mid-Atlantic Region Version 3. 3. January 

23, 2012. 

The 2007 point source inventory contained emissions for electric generating units 

(EGUs) and Non-EGU sources in Bucks, Chester, Delaware, Montgomery, and Philadelphia 

counties. EPA guidance for emissions inventory development provides that actual emissions 

should be used for purposes of the base year inventory. The point source inventory submitted 

was developed by MARAMA in consultation with PADEP using information compiled from 

2007 Annual Emissions Reports submitted to Pennsylvania from facilities in the state. In order 

to account for missing condensable PM emissions from EGUs the data was augmented using 

emission factors developed for MARAMA. 

The nonpoint source emissions inventory for 2007 was developed using 2007 specific 

activity data along with EPA emission factors and the most recently available emission 

calculation methodologies. 

For 2007 nonroad mobile sources, PADEP generated the emissions using EPA's 

NMIM2008 model. Since marine, air and rail/locomotive (MAR) emissions are not part of the 

NONROAD model, they were calculated separately outside of the NONROAD model. Aircraft 

emissions were developed using EPA's database to the support the 2008 NEI. PADEP used 

railroad emissions developed by the Eastern Regional Technical Advisory Committee (ERTAC). 

The 2007 onroad mobile source inventory was developed using EPA's highway mobile 

source emissions model MOVES2010a. PADEP used local activity to replace default inputs in 

the model where appropriate. 

OAMA staff reviewed the files and the emission results provided by P ADEP and found 

them to be acceptable. 
III. Projection Emissions Inventories for Maintenance Plan 

2017 and 2025 Projection Emission Inventories 

Projection inventories are used to show that the area will remain in attainment. PADEP 

used 2017 and 2025 emission projections developed through the MARAMA regional planning 

process for the interim and maintenance plan end year, respectively. Emission projections, 

emission methodologies and growth factors for 2017 and 2025 can be found in the Technical 

Support Document for the Development of the 20131201712020 Emission Inventories for 

Regional Air Quality Modeling in the Northeast/Mid-Atlantic Region (MARAMA 2017 TSD) 

and the Technical Support Document for the Development of the 2025 Emission Inventory for 

P M2.s Nonattainment Counties in the MANE- VU Region, January 2012 (MARAMA 2025 TSD), 

respectively. 

For EGU emissions, P ADEP used growth factors based on the Annual Energy Outlook 

(AE02011) and applied them to the 2007 inventory. Non-EGU emissions projections were 

based on Version 3.3 ofthe 2007 MANE-VU+VA inventory. MARAMA growth factors were 

developed using AEO fuel consumption forecasts, state-level employment projections, and other 

state-specific emission projection data. 

Nonpoint source emissions for 2017 and 2025 were developed similarly to the non-EGU 

point sources. Emission projections were based on Version 3.3 ofthe 2007 MANE-VU+VA 

inventory. MARAMA growth factors were developed using AEO fuel consumption forecasts, 

state-level employment projections, and other state-specific emission projection data. 

Nonroad source emissions for 2017 and 2025 were developed using NMIM model runs 

which contain default assumptions for projected years. Aircraft emissions were projected by 

applying activity growth data reported in the Federal Aviation Administration's (FAA's) 

Terminal Area Forecast (TAF) system for 2009-2030 (FAA2010). Railroad emissions were 

based on the MARAMA MANE-VU+Va inventory. 

The 2017 and 2025 onroad mobile source inventory was developed using EPA's highway 

mobile source emissions model MOVES2010. PADEP used local activity to replace default 

inputs in the model where appropriate 

OAMA staff reviewed the methodologies provided by P ADEP and found them to be 

acceptable.