Approval of the MOVES2010a
and EMFAC2007 Emissions Models
forTransportation Conformity
Hot-Spot Analyses, and Availability
of Modeling Guidance:
Questions and Answers
1. What action is EPA taking in today's Federal Register notice?
In today's Federal Register notice, EPA is approving the latest version of the Motor
Vehicle Emissions Simulator model (MOVESZOlOa) for official use for quantitative
carbon monoxide (CO) and particulate matter (PM2.5 and PM10) hot-spot analyses
for transportation conformity purposes outside of California. EPA is also approving
the latest version of the California EMission FACtor model (EMFAC2007) for quan-
titative PM hot-spot analyses for transportation conformity purposes within California,
EPA is also announcing a two-year transportation conformity grace period before use
of these models for these purposes is required.
While EPA is approving the MOVESZOlOa and EMFAC2007 models for project-
level transportation conformity purposes, today's notice is applicable to current and
future versions of the MOVES and EMFAC models, unless EPA notes otherwise
when approving the models for conformity purposes.
Finally, the notice announces the availability of two new EPA guidance documents
for: (1) completing quantitative PM hot-spot analyses using MOVES, EMFAC, and
other models, and (2) completing project-level CO analyses using MOVES,
The Federal Register notice, guidance documents, a fact sheet, and other documenta-
tion are available online at the EPA website: www.epa.gov/otaq/stateresources/trans-
conf/policy.htm. EPA and the Department of Transportation (DOT) will provide
outreach and training for using the guidance documents.
SEPA
United States
Environmental Protection
Agency
Office of Transportation and Air Quality
EPA-420-F-10-062
December 2010
-------
2. What is transportation conformity and what is a hot-spot analysis?
Transportation conformity is a Clean Air Act requirement that ensures that federally supported
highway and transit project activities are consistent with ("conform to") the state air quality
implementation plan (SIP). Conformity ensures that public health is protected by early consid-
eration of the air quality impact of transportation decisions in cities with air quality challenges.
Transportation conformity is required in nonattainment and maintenance areas for transporta-
tion-related criteria pollutants and national ambient air quality standards (NAAQS) (PM2.5,
PM10, ozone, CO, and nitrogen dioxide). A "hot-spot analysis" allows for the local air quality
impacts of a project to be considered before the project receives federal funding or approval.
3. For what purposes are these models being approved?
In today's notice, EPA is approving the MOVESZOlOa model for official use for completing
quantitative CO, PM2.5 and PM10 hot-spot analyses for transportation conformity purposes
(with a grace period - see Question #4). EPA previously approved MOVES2010 for use in SIPs
and transportation conformity regional emissions analyses in March 2010. MOVES2010a is a
minor update to the original MOVES2010 model,
Today EPA also is approving EMFAC2007 for official use when completing quantitative PM
hot-spot analyses for transportation conformity purposes within California (also with a grace
period - see Question #4). EPA previously approved EMFAC2007 for use in SIPs, regional
emissions analyses, and quantitative CO hot-spot analyses in January 2008. Nothing in today's
action affects that approval,
4. Is there a grace period for using these models for quantitative hot-spot analyses?
Today's Federal Register notice announces a two-year grace period before (1) the MOVES2010a
emissions model is required to be used in quantitative CO and PM hot-spot analyses for trans-
portation conformity purposes, and (2) the EMFAC2007 model is required to be used for PM
hot-spot analyses for transportation conformity purposes within California,
During the grace period in PM areas, the requirement to conduct qualitative analyses will
continue to apply, using previously issued joint EPA-Federal Highway Administration (FHWA)
guidance on such analyses. New quantitative PM hot-spot analyses started after the conclusion
of the grace period must use MOVES2010a or EMFAC2007 (within California). See Question
#5 for more on the quantitative PM hot-spot analysis guidance also released today,
During the grace period in CO areas outside of California, project sponsors will have the option
fl \ to use either MOVES2010a or EPA's MOBILE6.2 model. New quantitative CO hot-spot analyses
started after the conclusion of the grace period must use MOVES2010a,
~*
C'
-------
5. What is the quantitative PM hot-spot guidance?
Today's notice includes the announcement that EPA's final "Transportation Conformity Guid-
ance for Quantitative Hot-spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance
Areas" is available. This is conformity guidance for modeling the local air quality impacts of
certain transportation projects on the PM2.5 and PM10 NAAQS,
This guidance describes how to complete quantitative hot-spot analyses for certain highway and
transit projects in PM nonattainment and maintenance areas. This guidance describes confor-
mity requirements for hot-spot analyses, and provides technical guidance on estimating project
emissions with EPA's MOVES model, California's EMFAC model, and other methods. It also
outlines how to apply air quality models for PM hot-spot analyses and includes additional refer-
ences and examples. Finally, the guidance includes additional resources to assist state and local
agencies in conducting quantitative PM hot-spot analyses.
While this guidance addresses quantitative PM hot-spot analyses for transportation conformity
purposes, certain sections of this guidance may be applicable when completing air quality analyses
for transportation projects for other purposes,
rf
t A draft of this guidance was made available for public comment on May 26, 2010 with a closing
PH date of July 19, 2010 (75 FR 29537-29538). EPA received 15 sets of comments on the draft
guidance and considered these comments when developing its final guidance.
This guidance can be found on EPA's web site at: www.epa.gov/otaq/stateresources/transconf/
policy.htm.
6. What is the project-level CO guidance?
Today's notice also includes the announcement that EPA's final guidance document "Using
MOVES in Project-Level Carbon Monoxide Analyses" is available. This guidance describes
how to use the MOVES emissions model to estimate CO emissions from transportation projects,
including roadway intersections, highways, transit projects, parking lots and intermodal termi-
nals. This guidance can be applied when using MOVES to complete any project-level quanti-
tative CO analysis, including hot-spot analyses for transportation conformity determinations,
modeling project-level emissions for SIP development, and completing analyses pursuant to
the National Environmental Policy Act. This MOVES guidance applies in all states other than
California,
This guidance does not address air quality modeling for project-level CO analyses, as there are
other existing resources that support CO project-level analyses. For example, EPA's regulatory
recommendations for CO air quality modeling can be found in Appendix W to 40 CFR Part 51,
Users should also continue to consult the "1992 Guideline for Modeling Carbon Monoxide from
Roadway Intersections," (EPA-454/R-92-005, November 1992).
;
C
-------
Cfl
The new CO project'level MOVES guidance can be found on EPA's web site at: www.epa.gov/
otaq/stateresources/transconf/policy.htm.
7. How has EPA coordinated with other agencies and stakeholders on the actions taken in
today's notice?
As required by the transportation conformity rule, EPA consulted with the FHWA and Federal
Transit Administration (FTA) when establishing the two-year transportation conformity grace
period described in today's notice,
EPA also coordinated with FHWA and FTA when developing the guidance documents released
today. In addition, EPA worked with the California Air Resources Board (GARB) and the
California Department of Transportation (Caltrans) to develop the portions of the PM hot-spot
guidance relating to the use of CARB's EMFAC model in California,
Finally, EPA developed the guidance documents in coordination with state and local agencies
and other stakeholder groups. EPA considered comments from conformity stakeholders when
developing the final guidance documents.
8. Who do I contact for more information?
Any general questions regarding the actions taken today can be directed to Meg Patulski at:
U.S. Environmental Protection Agency
Office of Transportation and Air Quality
Transportation and Regional Programs Division
(734) 214-4842
E-mail: patulski.meg@epa.gov
Technical questions about completing emissions and air quality modeling for hot-spot analyses
can also be sent to:
conformity-hotspot@epa.gov
For specific questions concerning using the guidance documents for a project in a particular
nonattainment or maintenance area, please contact the transportation conformity staff person
responsible for your state at the appropriate EPA Regional Office. Contact information for EPA
Regional Offices can be found at:
www.epa.gov/otaq/stateresources/transconf/contacts.htm
cx
------- |