UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION III 1650 Arch Street Philadelphia, Pennsylvania 19103

DATE: August 27,2015

SUBJECT: Technical Support Document (TSD)- Insignificance Findings for the Motor Vehicle Emissions for the Liberty-Clairton, Pennsylvania (PA) 1997 and 2006 Fine Particulate Matter(PM2.s) National Ambient Air Quality Standards (NAAQS) Nonattainment Area

FROM:

TO:

THRU: Administrative Record for the Insignificance Findings for the Motor Vehicle Emissions for the Liberty-Clairton, PA 1997 and 2006 PM2

.sNAAQS**Nonattainmen~** Area \')

## /1~-p;_/~**f~.t7**/tS CristinaFernandez, Associate Director

Office ofAirProgram Planning (3AP30)

I. Background

OnJune 21, 2013, the Commonwealth ofPennsylvaniaDepartment ofEnvironmental Protection (PADEP) submitted, on behalfofAllegheny County, a formal revision to its State Implementation Plan (SIP). The SIP revision consisted ofthe 2006 24-hour PM2

.sNAAQS attainment plan for the Liberty-Clairton Area, which included among other things, an attainment demonstration, a 2007 base year emissions inventory, a reasonably available control measures (RACM) analysis, and a description ofcontingency measures. On July 31, 2014, PADEP formally submitted a supplementto the attainment demonstration for the 2006 PM2

.sNAAQS for the Liberty-Clairton Area in order to include a request for findings ofinsignificance by Environmental ProtectionAgency (EPA) for motor vehicle emissions for nitrogen oxides (NOx) and direct PM2.s. Using emissions inventories and modeling already included as part ofthe June 21, 2013 SIP submittal, the supplemental SIP revision demonstrates that motor vehicle emissions for direct PM2

.s and NOx are insignificant contributors to the air quality problem inthe Liberty Clairton Areafor both the 1997 and 2006 PM2.s NAAQS.
Transportation conformity is required under section 176(c) ofthe Clean Air Act (CAA) to ensure that federally supported highway, transitprojects, and other activities are consistent with, I

II. Administrative Requirements for Making Adequacy and Insignificance Findings

EPA has followed the process for reviewing the submitted SIP and determining ifan insignificance finding for motor vehicle emissions is warranted in accordance with the procedures listed in the January 2008 Conformity Regulations contained in 40 CFR 93.102(b)- "Geographical applicability," which applies to all nonattainment and maintenance areas for transportation-related criteria pollutants for which the area is designated nonattainment or has a maintenance plan, and 40 CFR 93.118(f)- "Adequacy reviewprocess for implementationplan submissions," which describes the procedures for reviewing the adequacy ofan implementation plan submittal. Along with a direct final rule notice (DFRN), EPA will be issuing a short notice ofproposedrulemaking (NPR) for a 30-daypublic commentperiod soliciting public comment for the approvability ofthe Commonwealth ofPennsylvania's SIP submission. During this time, the public will have the opportunity to comment onthe adequacy/approvability ofthe insignificance findings in the SIP revision. IfEPA receives such comments, it will publish a timely withdrawal ofthe DFRN in the Federal Register and inform the public that the rule will not take effect, which includes the adequate and approved insignificance findings for both the 1997 and 2006 PM2

.sNAAQS.



### III. Review ofthe Submitted Modeling Utilizing the Motor Vehicle Emission Simulator (MOVES2010)

The highway mobile source emission inventory was developed using available travel data and EPA's MOVES2010a emission model. To utilize the MOVES2010a model, several different models were used to provide the necessary inputs into MOVES201 Oa. One ofthe models, PPSUITE, was utilized to provide inputs as well as to post-process the output files from MOVES2010a.

The appropriate traffic related inputs which were processed by PPSUITE were input into MOVES2010a. Additional traffic related inputs as well as non-traffic related inputs were provided as well. The data was input into MOVES2010aviathe county data manager. The county data manager is a function ofthe MOVES2010a model which allows county specific data inputs to be converted into a usable form by MOVES2010a. At that point a Run Specification (RunSpec), whichis a function ofMOVES201 Oa that allows the user to input necessary parameters into the model, was created and run in batch mode. The outputs were provided as an inventory because vehicle miles traveled (VMT) and vehicle population were provided to MOVES2010a.

EPA reviewed the modeling methodology utilized by PADEP and all modeling related information to produce the motor vehicle emissions inventory for years 2007 and 2014. EPA found that all necessary and required modeling procedures were followed in the production ofthe 2007 and 2014 motor vehicle emissions inventory which were produced using MOVES2010a.

IV. Evaluation ofthe Request for an Insignificance Finding for Motor Vehicle Emissions

3(VOCs), sulfur dioxide (S02) PM2.s mobile emissions. The

or Ammonia (NH3) are a June 21, 2013 SIP submittal significant contributorto the does not rely on reductions of mobile PMemissions or does VOCs orNH3 from any the implementation plan sources inthe area. The SIP submission establish a submittal does rely on so2 budget for VOCs, S02 or emissions reductions from NH3 as part ofthe PM2.s point sources; however, it attainment demonstration? does notrely onreductions from onroad S02 sources, which represented less than two tenths ofone percent (<0.2%) ofthe area's total S02 emissions inthe 2007 and 2014 projected emissions. Therefore, MVEBs were not established for these precursors. 93.102(b)(3) Has the EPA or the The Commonwealthhas Commonwealthmade a requested that direct PM be finding that direct PMis a found an insignificant significant contributor to the contributor to the mobile PM PM mobile emissions or does emissions. This request is the implementationplan based onthe Commonwealth's establish a budget that finding that onroad mobile includes direct PM as part of source PM2.s constitutes less the PM2.s attainment than one percent (<1%) ofthe demonstration? area's total 2007 PM2.s emissions and the area'stotal projected 2014 PM2.s emissions due to continuing

, fleet turnover even with future VMT growth included in the emissionprojections. Sec. 93.118(e)(4)(i) Was the submitted revised Yes. The SIP was endorsed plan endorsed by the and submitted by the Governor (or his orher Governor's designee, E. designee) and subjectto a Christopher Abruzzo, the State public hearing? Secretary ofthe Pennsylvania Department ofEnvironmental Protection. A public hearing

onthe SIP proposal was held

onDecember 18,2013. Sec. 93.118(e)(4)(ii) Before the implementation Yes. Consultation has

5emissions; any changes to established safety margins (see Sec. 93.101 for definition); and reasons for the changes (including the basis for any changes related to emission factors or estimates ofvehicle miles traveled). Sec. 93.118(e)(5) Didthey provide and we There were no comments on reviewpublic comments and the SIP related to the proposed the Commonwealth's insignificance finding request. responses to those comments with the submitted control strategy SIP?

The requirements under 40 CFR 93.109(f) bases insignificance on emissionpercentages, emissiontrends, and the effectiveness ofthe pollutant in forming PM. Based upon our review and evaluation ofthe motor vehicle emissions contained inthe Attainment Demonstration for the Liberty-Clairton, PA 1997 and 2006 

### PMz

.sNAAQS Nonattainment Area, EPA finds that the SIP submittal meets the criteria inthe transportation conformityrules for an insignificance finding for NOx and 

### PMz.s contribution from motor vehicles. Weighing all the factors for an insignificance finding, particularly the minor contribution ofmobile source 

### PMz.s and NOx, EPA has determined that the 

### PMz.s andNOx contribution from motor vehicle emissions to the 

### PMz.s pollution for the Liberty-ClairtonNonattainment Areais insignificant.

The first criteriarequires that the motor vehicle emissions constitute a lowpercentage ofthe total SIP inventory. The submitted SIP satisfies this requirement. In particular, for the 2007 base year, the direct PM onroad mobile source constitutes 0.99% ofthe area's total 

### PMz.s emissions and decreases inthe later analysis yearto 0.88% (2014). For the 2007 base year, theNOx onroad mobile source constitutes 4.9% ofthe area's total NOx emissions and decreases inthe later analysis yearto 3.07% (2014). The SIP submittal does rely on 

### SOz emissions reductions from point sources; however, it does notrely on reductions from onroad 

### SOz sources, which represented less than 0.2% ofthe total 

### SOz inventory for the area.

The second criteriarequires that the current state ofair quality is showing attainment based on monitoring data in the Liberty-Clairton Area. Currently, monitoring data shows that the LibertyClairton Area is attaining boththe 1997 and 2006 

### PMz.sNAAQS. EPAhas determined thatthe Liberty-Clairton Area attained the 1997 NAAQS by its attainment date, based on 2009-2011 monitoring data (October 25,2013, 78 FR 63881). OnJuly 10,2015 (80 FR 39696), EPA determined that the Liberty-Clairton Area had attained the 2006 24-hour 

### PMz.s NAAQS, based

on quality-assured and certified ambient air quality data for the 2012-2014 monitoring period. As a result, ofEPA's determinations for boththe 1997 and 2006 

### PMz.s NAAQS the second criteriahas been satisfiedbythe Liberty-Clairton Area.

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