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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION III

1650 Arch Street

Philadelphia, Pennsylvania 19103

 August 26, 2013 

SUBJECT: Supplemental Technical Support Document - Adequacy Findings for the Motor 

Vehicle Emissions Budgets in the Attainment Demonstration for the Delaware 

Portion of the Philadelphia-Wilmington-New Jersey 1997 Fine Particulate (PM2.5)

National Ambient Air quality Standard (NAAQS) Nonattainment Area 

FROM:

 /s/

Gregory Becoat, 

Office of Air Program Planning (3AP30)

TO: Administrative Record for the Adequacy Findings for the Motor Vehicle 

Emissions Budgets in the Attainment Demonstration for the Delaware Portion of 

the Philadelphia-Wilmington-New Jersey City 1997 PM2.5 NAAQS 

Nonattainment Area 

 /s/

THRU: Cristina Fernandez, Associate Director,

Office of Air Program Planning (3AP30)

I. Background

On April 3, 2008, the Delaware Department of Natural Resources and Environmental Control 

(DNREC) formally submitted a State Implementation Plan (SIP) revision to satisfy the attainment 

demonstration requirements of the Clean Air Act (CAA) pursuant to the 1997 PM2.5 NAAQS for 

the Philadelphia-Wilmington-New Jersey PM2.5 Nonattainment Area. On April 25, 2012, DNREC 

submitted a formal supplement to the SIP revision that was submitted on April 3, 2008 in order to: 

(1) replace the MOBILE6.2 model on-road mobile emission budget with a budget that is based on 

the Motor Vehicle Emissions Simulator (MOVES) model for milestone year 2009; (2) demonstrate 

that the MOVES-based mobile source budget is consistent with attainment of the 1997 PM2.5

NAAQS by 2010; (3) demonstrate that the contingency requirements of the CAA are met; and (4) 

establish out-year 2012 on-road mobile emissions budget for New Castle County for PM2.5 and

nitrogen oxides (NOx). 

On November 20, 2012, EPA posted a notice on EPA’s website at 

http://www.epa.gov/otaq/stateresources/transconf/currsips.htm for the purpose of opening EPA’s 

30-day public comment period on the adequacy/approvability of the budgets in the SIP revision 

and to inform the public of the availability of the SIP on www.regulations.gov, docket 

number EPA–R03–OAR–2010–0141. EPA’s adequacy review of the motor vehicle emissions 

budgets and the opportunity for public comment on the SIP revision were concurrent. A Notice of 

Proposed Rulemaking (NPR) was published in the Federal Register on November 19, 2012 (77 FR 
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69399) proposing approval of the revision to the SIP in accordance with the requirements of the 

CAA.

The purpose of this supplemental technical support document (TSD) is to reflect corrections of 

typographical errors on the technical support document associated with the NPR published on 

November 19, 2012 (77 FR 69399) entitled, “Technical Support Document - Adequacy Findings 

for the Motor Vehicle Emissions Budgets in the Attainment Demonstration for the Delaware 

Portion of the Philadelphia-Wilmington-New Jersey 1997 Fine Particulate (PM2.5) National 

Ambient Air quality Standard (NAAQS) Nonattainment Area,” and to establish out-year 2012 onroad mobile emissions budget for New Castle County for PM2.5 and NOx. 

II. Transportation Conformity Requirements

Under section 176(c) of the CAA, new transportation plans, programs, and projects, such as the 

construction of new highways, must “conform” to (i.e., be consistent with) the part of the state’s 

air quality plan that addresses pollution from cars and trucks. The CAA requires federal actions in 

nonattainment and maintenance areas to “conform to” the goals of SIP. This means that such 

actions will not cause or contribute to violations of NAAQS; worsen the severity of an existing 

violation; or delay timely attainment of any NAAQS or any interim milestone. 

For motor vehicle budgets (MVEBs) to be approvable, they must meet, at a minimum, EPA’s 

adequacy criteria found at 40 CFR 93.118(e)(4). EPA’s adequacy criteria are: (1) the submitted 

control strategy implementation plan was endorsed by the Governor or designee and was subject to 

a State public hearing; (2) consultation among Federal, State, and local agencies occurred; full 

implementation plan documentation was provided to EPA; and EPA's stated concerns, if any, were 

addressed before the control strategy implementation plan was submitted; (3) the MVEBs are 

clearly identified and precisely quantified; (4) the MVEBs, when considered together with all other 

emissions sources, are consistent with applicable requirements for maintenance; (5) the MVEBs 

are consistent with and clearly related to the emissions inventory and the control measures in the 

submitted control strategy implementation plan; and (6) revisions to previously submitted 

maintenance plans explain and document any changes to previously submitted budgets and control 

measures; impacts on point and area source emissions; any changes to established safety margins; 

and reasons for the changes (including the basis for any changes related to emission factors or 

estimates of vehicle miles traveled).

III. Administrative Requirements for Making Adequacy Findings 

We have followed the process for determining the adequacy of the submitted SIP MVEBs in 

accordance with the procedures listed in the January 2008 Conformity Regulations contained in 40 

CFR part 93, 118(f) “Adequacy review process for implementation plan submissions.” EPA will 

be issuing a supplemental NPR for a 30-day public comment period soliciting public comment for

the approvability of Delaware’s SIP submission. The supplemental NPR also proposes approval of 

the changes to the MVEBs for milestone year 2009 and the out-year 2012 on-road mobile 

emissions budget for New Castle County for PM2.5 and NOx. Concurrently with EPA’s

supplemental NPR, a notice will be posted on EPA’s website at 

http://www.epa.gov/otaq/stateresources/transconf/currsips.htm for the purpose of opening EPA’s 
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30-day public comment period on the adequacy/approvability of the budgets in the SIP revision. 

That notice will inform the public of the availability of the Delaware SIP revision on its own 

website. EPA’s website notice will provide a link to the address for the website where interested 

members of the public could access the SIP revision. Following EPA’s public comment period, 

responses to any comments received on the proposed mobile budgets in the Delaware SIP will be 

addressed in an amendment to this TSD.

As stated previously, a typographical error was made on the MVEBs for year 2009 in the TSD 

associated with the NPR published on November 19, 2012 and are corrected in Table 1 as follows:

Table 1

The Budgets of the Delaware Portion of the Philadelphia-Wilmington-New Jersey 1997 

PM2.5 NAAQS Attainment Demonstration

Plan

Submittals

Milestone 

Year

Mobile Vehicle 

Emissions Budget 

for Direct PMTons Per Year

Mobile Vehicle 

Emissions Budget for 

NOx-Tons Per Year

Attainment Plan 

Demonstration

2009 257 8,448

Shown below in Table 2 are the 2 sets of budgets established as the 2012 on-road mobile emissions 

budget for New Castle County for PM2.5 and NOx.

Table 2

The 2012 out-year budgets of the Delaware Portion of the Philadelphia-Wilmington-New 

Jersey 1997 PM2.5 NAAQS Attainment Demonstration

Plan

Submittals

Out-Year Mobile Vehicle 

Emissions Budget 

for Direct PM-Tons 

Per Year

Mobile Vehicle 

Emissions Budget 

for NOx-Tons Per 

Year

Attainment Plan 

Demonstration

2012 199 6,273

IV. Evaluation of the Adequacy of the MVEBs Budgets in the Attainment Demonstration 

for the Delaware Portion of the Philadelphia-Wilmington-New Jersey 1997 NAAQS PM2.5 

Nonattainment Area Submitted by DNREC on April 25, 2012

In this TSD, we are evaluating the MVEBs associated with the 2009 attainment demonstration 

plan contained in the April 25, 2012 SIP revision, for conformity purposes. We are using the 

evaluation criteria detailed in the Transportation Conformity Rule, 40 CFR part 93.102(b)(2)(v), 

93.102(b)(2)(v), 93.102(b)(3), and part 93, 93.118(e)4 through 93.118(e)5. The evaluation is 
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presented in Table 3, below.

Table 3

Adequacy of the MVEBs Contained in the Attainment Demonstration for the Delaware 

Portion of the Philadelphia-Wilmington-New Jersey 1997 NAAQS PM2.5 Nonattainment

Area

Transportation Conformity

Rule

40 CFR Part 93, 93.118

Review Criteria Was the Criterion Satisfied? 

If Yes How was this Criteria 

Satisfied?

93.102(b)(2)(iv) Have EPA and the State 

made a finding that NOx is 

an insignificant contributor 

to the direct mobile PM 

emissions?

EPA and the State have not 

made such a finding.

93.102(b)(2)(v) Has EPA or State made a 

finding that VOCs, Sulfur 

Oxides (SOx) or Ammonia 

(NH3) as precursors to be a 

significant contributor to the 

mobile PM2.5 emissions?

Neither EPA or the State has 

made such a finding.

93.102(b)(3) Has the EPA or the State 

made a finding that reentrained road dust is a 

significant contributor to the 

PM mobile emissions?

Neither EPA or the State has 

made such a finding.

Sec. 93.118(e)(4)(i) Was the submitted revised 

plan endorsed by the 

Governor (or his or her 

designee) and subject to a 

State public hearing?

Yes. The submitted 

attainment demonstration was 

endorsed and submitted as a 

SIP revision by the 

Governor’s designee, the 

Secretary of the DNREC, and 

a public hearing was held on 

December 28, 2011.

Sec. 93.118(e)(4)(ii) Before the attainment 

demonstration was submitted 

to EPA, did consultation 

between federal, State and 

local agencies occur; was full 

implementation plan 

documentation provided to 

EPA, and was EPA’s stated 

concerns, if any, addressed?

Yes. Consultation has 

occurred among all required 

federal, state and local 

agencies.
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Sec. 93.118(e)(4)(iii) Was the motor vehicle 

emissions budget(s) clearly

identified and precisely 

quantified?

Yes, the budgets are clearly

identified on pages 7 and 8 

(Sections 2 and 3) of the 

April 25, 2012 submittal 

containing the revised 

attainment demonstration. 

Sec. 93.118(e)(4)(iv) Is the motor vehicle 

emissions budget(s), when 

considered together with all 

other emission reductions, 

consistent with applicable 

requirements for attainment 

demonstrations?

EPA believes the budgets can 

be declared adequate because 

in conjunction with the other 

emission reductions, they 

demonstrate attainment for 

2010 and the chosen out-year 

of 2012 is appropriate. 

Sec. 93.118(e)(4)(v) Is the motor vehicle 

emissions budget(s) 

consistent with and clearly 

related to the emissions 

inventory and the control 

measures in the Plan?

EPA believes that the budgets 

are clearly related to the 

emissions inventory and the 

control measures in the SIP 

submittal.

Sec. 93.118(e)(4)(vi) Revisions to previously

submitted attainment 

demonstrations: explain and 

document any changes to 

previously submitted budgets 

and control measures; 

impacts on point and area 

source emissions; 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 of vehicle miles 

traveled).

Yes. The plan explains that 

the additional budgets are 

established for the purpose of 

conformity determinations 

for years beyond the 

attainment year.

Sec. 93.118(e)(5) Did they provide and we 

review public comments and 

the State’s responses to those 

Yes
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comments with the submitted 

control strategy SIP?

V. Findings

Based upon our review and evaluation of the MVEBs contained in DNREC’s April 25, 2012

submittal of the attainment plan for the Delaware 1997 PM2.5 NAAQS nonattainment area, we 

find the MVEBs adequate for conformity purposes.