Technical Support Document (TSD) for 

Emissions Inventories for the State Implementation Plan Revision: 

NOx Vehicle Emission Budget Revisions Based on MOVES 2010a 

Allentown-Bethlehem-Easton, P A 

1997 Eight-Hour Ozone Maintenance Area 

Submitted by the Bureau of Air Quality 

Pennsylvania Department of Environmental Protection 

TSD Prepared March 2014 by 

Jessica L. Fry 

Office ofAir Monitoring and Analysis, 3AP40 

U.S. Environmental Protection Agency, Region 3 

1650 Arch Street 

Philadelphia, Pennsylvania 19103 

Reviewed by Alice H. 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 State Implementation Plan (SIP) Revision: NOx Motor Vehicle Emission Budget 

Revisions Based on MOVES 2010a for Allentown-Bethlehem-Easton (ABE) 1997 EightHour Ozone Maintenance Plan submitted by the Pennsylvania Department of 

Environmental Protection (PADEP). The ABE Nonattainment Area consists of Carbon, 

Lehigh, and Northampton counties in Pennsylvania (P A). P ADEP is updating their NOx 

motor vehicle emissions budgets submitted in their 1997 Eight-hour Ozone SIP for t4e 

ABE Area for the years 2009 and 2018 using MOVES2010a and subsequently reviewing 

and updating (if needed) the NOx emissions inventories for point, nonpoint, nonroad, and 

onroad sources. Emission inventories in the ABE Area SIP revision are used to 

document that the SIP continues to meet applicable requirements when previous onroad 

mobile emissions inventories are replaced with MOVES2010a inventories. The plan 

should also demonstrate that growth and control strategy assumptions for point, nonpoint, 

and nonroad mobile sources continue to be valid. This review is to confirm that any 

minor updates have not changed the overall conclusions of the SIP. Any questions 

pertaining to this technical summary should be directed to Alice Chow, Associate 

Director, Office of Air Monitoring and Analysis, at 215-814-2144 or via email at 

chow.alice@epa. gov. 

II 2009 and 2018 Emissions Inventories 

In the ABE Area SIP revision, emissions inventories are used to support the States 

claim that the area is continuing to attain the 1997 eight-hour ozone standard as set forth 

in the SIP when using MOVES 2010a for the onroad mobile emissions inventory. In 

order to do this, the state should review the point, nonpoint, and nonroad NOx emissions 

inventories submitted with the SIP for the interim (2009) and attainment (20 18) years and 

determine if changes in growth and control strategy assumptions affect the conclusion 

that the area will remain in compliance with the 1997 eight-hour ozone standard. 

In the ABE Area SIP revision, P ADEP analyzed the NOx point source emissions 

estimates for 2009 and 2018 submitted with the Eight-Hour Ozone NAAQS ABE Area 

SIP. PADEP has resubmitted point source emissions inventories for 2009 and 2018. For 

the 2009 point source inventory, PADEP submitted actual2009 emissions from 

individual facilities in the area. The emissions were submitted in tons/year and tons/day. 

For the 2018 projected inventories P ADEP used information developed for the 

MARAMA 2011 regional modeling effort and did a straight-line interpolation between 

the 2007 MARAMA baseline inventory and the 2020 MARAMA projected year 

inventory. It was concluded that the emissions had been overestimated in the SIP and 

that the area will continue to be in attainment with the new emission estimates. OAMA 

staff reviewed the analysis and believes it is reasonable. 
Pennsylvania conducted an analysis of the NOx emissions estimates for nonpoint 

sources submitted for 2009 and 2018 with the 1997 ozone NAAQS ABE Area SIP to 

determine if the nonpoint NOx emissions inventory needed to be updated for this revision. 

For the 2009 nonpoint source emissions Pennsylvania compared U.S. Department of 

Commerce, Bureau of Census, and the Energy Information Administration, U.S. 

Department of Energy actual growth from 2002-2009 to the growth estimates used in the 

ABE Area SIP. Pennsylvania concluded that updated growth factors for fuel use show 

that growth was over-predicted in the original maintenance plan and therefore the 

non point emissions are not being updated. OAMA staff reviewed the analysis and 

believes it is reasonable. 

The nonroad emissions inventory estimates for NOx submitted for 2009 and 2018 

in the ABE Area SIP were calculated using USEPA's NONROAD2005 Model. 

Pennsylvania compared growth estimates used in the NONROAD2005 to the growth 

estimates in the current NONROAD2008a. These comparisons along with fleet turnover 

and the effects of the recession led Pennsylvania to the conclusion that the general 

downward trend in NOx emissions in this sector supports the conclusion that the area will 

continue to maintain compliance with the eight-hour ozone standard and therefore no 

revisions were made. OAMA staff reviewed the analysis and believes it is reasonable. 

In the ABE Area SIP revision, onroad emissions were estimated using the 

MOVES20 1 Oa model by Michael Baker, Jr., Inc., who is a consultant to the Pennsylvania 

Department ofTransportation (PennDOT). PADEP revised the 2004 and 2009 onroad 

NOx emissions inventories and the 2018 projection inventory for the Reading Area SIP 

revision. Pennsylvania used the same Statistical Evaluation of Projected Traffic method 

for forecasting traffic growth or vehicle miles travelled. New input files for use in 

MOVES 2010a were developed using the local data from PennDOT, with some inputs 

being developed by the software PPSUITE, which is a tool for estimating speeds and 

processing emissions rates based upon accepted transportation engineering 

methodologies. Mobile emissions values were given in units of tons per summer day. 

OAMA staff reviewed the emissions and believes them to be reasonable. 
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