UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION III

1650 Arch Street

Philadelphia, Pennsylvania 19103

                                                                        
                                 



SUBJECT:	                                                               
                         June 17, 2013

Supplemental Technical Support Document (TSD) - Insignificance Findings
for the Motor Vehicle Emissions for the Redesignation Request and
Maintenance Plan for the West Virginia Portion of the
Parkersburg-Marietta, WV-OH 1997 Fine Particulate Matter (PM2.5)
Nonattainment Area 





FROM:	       /s/

Gregory Becoat 

Environmental Scientist (3AP30)	





TO:	

Administrative Record for the Insignificance Findings for the Motor
Vehicle Emissions for the Redesignation Request and Maintenance Plan for
West Virginia Portion of the Parkersburg-Marietta, WV-OH 1997 PM2.5
Nonattainment Area 

	





THRU:	          /s/

Cristina Fernandez, Associate Director 

Office of Air Program Planning (3AP30)	





I. Background

On March 8, 2012, the State of West Virginia formally submitted a
Redesignation Request and Maintenance Plan for West Virginia Portion of
the Parkersburg-Marietta, WV-OH 1997 PM2.5 Nonattainment Area (hereafter
the Redesignation Request and Maintenance Plan).  The State
Implementation Plan (SIP) included a request for a finding of
insignificance by EPA for motor vehicle emissions for nitrogen oxides
(NOx), direct particulate matter (PM), and sulfur dioxide (SO2).

Transportation conformity is required under section 176(c) of the Clean
Air Act (CAA) to ensure that federally supported highway, transit
projects, and other activities are consistent with (conform to) the
purpose of the SIP.  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 a
national ambient air quality standard (NAAQS); worsen the severity of an
existing violation; or delay timely attainment of any NAAQS or any
interim milestone.  Actions involving Federal Highway Administration
(FHWA) or Federal Transit Administration (FTA) funding or approval are
subject to the transportation conformity rule (40 CFR part 93, subpart
A).  Under this rule, metropolitan planning organizations (MPOs) in
nonattainment and maintenance areas coordinate with State air quality
and transportation agencies, EPA, FHWA, and FTA to demonstrate that
their metropolitan transportation plans and TIPs conform to applicable
SIPs.  This is typically determined by showing that estimated emissions
from existing and planned highway and transit systems are less than or
equal to the motor vehicle emissions budgets (MVEBs) contained in a SIP.

For 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).

In certain instances, the Transportation Conformity Rule allows areas to
forgo establishment of a MVEB where it is demonstrated that the regional
motor vehicle emissions for a particular pollutant or precursor are an
insignificant contributor to the air quality problem in an area.  The
general criteria for insignificance determinations can be found in 40
CFR 93.109(f). Insignificance determinations are based on a number of
factors, including the percentage of motor vehicle emissions in the
context of the total SIP inventory; the current state of air quality as
determined by monitoring data for the relevant NAAQS; the absence of SIP
motor vehicle control measures; and the historical trends and future
projections of the growth of motor vehicle emissions.  EPA’s rationale
for providing for insignificance determinations is described in the July
1, 2004, revision to the Transportation Conformity Rule at 69 FR 40004. 
Specifically, the rationale is explained on page 40061 under the
subsection XXIII.B. entitled, “Areas With Insignificant Motor Vehicle
Emissions.”  Any insignificance determination under review of EPA is
subject to the adequacy and approval process for EPA's action on the
SIP.

II.  Administrative Requirements for Making Insignificance Findings  

EPA has followed the process for reviewing the submitted SIP and
determining if an 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” and 40 CFR 93.118(f) - “Adequacy review process for
implementation plan submissions.”  

III.  Evaluation of the Request for an Insignificance Finding for Motor
Vehicle Emissions in the Redesignation Request and Maintenance Plan for
the West Virginia Portion of the Parkersburg-Marietta, WV-OH  1997 PM2.5
 Nonattainment Area Submitted by The West Virginia Department of
Environmental Protection 

In this TSD, EPA is evaluating the West Virginia Department of
Environmental Protection’s request for an insignificance finding for
motor vehicle emissions associated with the Redesignation Request and
Maintenance Plan contained in the submittal.  EPA is using the
evaluation criteria detailed in the Transportation Conformity Rule, 40
CFR 93.102(b)(2)(iv), (b)(2)(v), and (b)(3) and 93.118(e)(4) and (e)(5).
 The evaluation is presented below.

Review of the Request for Insignificance Finding of Motor Vehicle
Emissions in the Redesignation Request and Maintenance Plan for the West
Virginia Portion of the Parkersburg-Marietta, WV-OH PM2.5 Nonattainment
Area 

Transportation Conformity Rule

40 CFR Part 93	

Review Criteria	

Was the Criterion Satisfied?  If Yes, How was this Criteria Satisfied?

93.102(b)(2)(iv)	Has the EPA and the State made a finding that NOx is an
insignificant contributor to the direct mobile PM emissions or does the
implementation plan fail to establish a NOx budget as part of the PM2.5
maintenance strategy?

	The State has requested that NOx be found an insignificant contributor
to the mobile PM emissions.  This request is based on the State finding
that Onroad mobile source NOx constitutes less than twelve percent of
the area’s total NOx emissions in the 2015 and 2022 horizon years due
to continuing fleet turnover even with future vehicle miles traveled
(VMT) growth included in the emission projections. EPA has also made a
finding that the transportation-related emissions of NOx within the
nonattainment area are not a significant contributor to the direct
mobile PM emissions.

93.102(b)(2)(v) 	Has the EPA or State made a finding that the
precursors, Volatile Organic Compounds (VOCs), SO2 or Ammonia (NH3) are
a significant contributor to the mobile PM emissions or does the
implementation plan  submission establish a  budget for VOCs, SOx or NH3
as part of a PM2.5  maintenance strategy?	Neither EPA nor the State has
made any findings that VOCs, SO2, or NH3 is a significant contributor to
the PM2.5 mobile emissions, and therefore, it has not been included in
the SIP.  Onroad mobile source SO2 emissions constitute less than 0.1%
of the area’s total SO2 emissions in the 2015 and 2022 horizon years.

93.102(b)(3)

	Has the EPA or the State made a finding that direct PM is a significant
contributor to the PM mobile emissions or does the implementation plan 
establish a budget that includes direct PM as part of a PM 2.5
maintenance strategy?

	The State has requested that direct PM be found an insignificant
contributor to the mobile PM emissions.  This request is based on the
State finding that Onroad mobile source PM2.5 constitutes less than 2.1%
of the area’s total PM2.5 emissions in the 2015 and 2022 horizon years
due to continuing fleet turnover even with future VMT growth included in
the emission projections. 

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 Redesignation Request and Maintenance Plan was
endorsed and submitted as a SIP revision by the Governor’s designee,
the Secretary of the West Virginia Department of Environmental
Protection.  A public hearing on the SIP proposal was held on February
23, 2012. 

Sec. 93.118(e)(4)(ii)	Before the maintenance plan 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.

Sec. 93.118(e)(4)(iii)	Were the MVEBs clearly identified and precisely
quantified?	As there was a request for an insignificance finding, no
MVEBs were identified in the SIP.  

Sec. 93.118(e)(4)(iv)	Are the motor vehicle emissions, when considered
together with all other emission reductions, consistent with applicable
requirements for maintenance strategies?	EPA believes that motor vehicle
emissions can be declared insignificant contributors because in
comparing the motor vehicle emissions to the overall emissions
inventory, the motor vehicle emissions comprise only a small portion of
the over PM2.5 emissions for the nonattainment area and are projected to
continue to significantly decline due to fleet turnover.

Sec. 93.118(e)(4)(v)	Are the motor vehicle emissions consistent with and
clearly related to the emissions inventory and the control measures in
the Plan?

	EPA believes that the motor vehicle emissions have clearly related to
the emissions inventory and control measures in the SIP submittal.

Sec. 93.118(e)(4)(vi)	Revisions to previously submitted maintenance
plan: 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).	There are
no revisions to the maintenance plan because this is the initial
redesignation request, along with the associated maintenance plan for
West Virginia Portion of the Parkersburg-Marietta, WV-OH Area.



Sec. 93.118(e)(5)	Did they provide and we review public comments and the
State’s responses to those comments with the submitted control
strategy SIP?	There were no comments on the SIP related to the proposed
insignificance finding request.



IV.  Conclusion 

Based upon our review and evaluation of the motor vehicle emissions
contained in the West Virginia Redesignation Request and Maintenance
Plan for the West Virginia Portion of the Parkersburg-Marietta, WV-OH
1997 PM2.5 Nonattainment Area, EPA finds that the SIP submittal meets
the criteria in the transportation conformity rules for an
insignificance finding for NOx, PM2.5, and SO2 contribution from motor
vehicles.  Weighing all the factors for an insignificance finding,
particularly the minor contribution of mobile source PM2.5 and SO2, EPA
has determined that the PM2.5 and SO2 contribution from motor vehicle
emissions to the annual PM2.5 pollution for the West Virginia portion of
the Nonattainment Area are insignificant.  With respect to
transportation conformity, the larger NOx contribution of less than
twelve and a half percent of the area’s total NOx emissions in the
2015 and 2022 horizon years requires further justification to request an
insignificant finding.  The requirements under 40 CFR 93.109(f) bases
insignificance on emission percentages, emission trends, and the
effectiveness of the pollutant in forming PM.  For the
Parkersburg-Marietta area, there is a significant emission decrease
projected for the highway sector and total emissions source inventory in
years 2008, 2015, and 2022.  Given the relatively small contribution of
the highway mobile emissions to the total SIP inventory, highway mobile
emissions are not likely to contribute significantly to local PM2.5. 
Additionally, NOx reductions are significantly less effective in
reducing PM concentrations than are reductions in direct PM and SO2. 
Consequently, NOx percentage emission contribution may be higher than
direct PM and SO2 without adversely affecting air quality.  Based on the
analysis of local historical trends and growth patterns in order to
develop the long range transportation plan and transportation
improvement program for transportation conformity purposes, EPA has no
reason to expect highway motor vehicle emissions growth to lead to a
violation of the annual PM2.5 standard.  Although vehicle miles traveled
increases over time, NOx emissions are projected to decrease
dramatically from 4505.4 tons/year in 2002 to 665.7 tons/year in 2030. 
This demonstrates that highway emissions will remain insignificant in
the future.  Upon review of the further justification for requesting an
insignificant finding for NOx, EPA has determined that NOx contribution
from motor vehicle emissions to the annual PM2.5 pollution for the West
Virginia portion of the Nonattainment Area is insignificant.  

 

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