[Federal Register Volume 79, Number 9 (Tuesday, January 14, 2014)]
[Pages 2437-2441]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2014-00564]



[EPA-HQ-OAR-2013-0809; FRL-9905- 43-OAR]

Notice of Availability of the Environmental Protection Agency's 
2018 Emissions Modeling Platform

AGENCY: Environmental Protection Agency (EPA).

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ACTION: Notice of data availability (NODA).


SUMMARY: The Environmental Protection Agency (EPA) is providing notice 
that the 2018 Emissions Modeling Platform data are available for public 
review and comment. The 2018 Emissions Modeling Platform consists of 
emission inventory data, supporting data used to develop the 2018 
emission inventories, and methods and data that are used to process 
emission inventories representing the year 2018 into a form that can be 
used for air quality modeling. The platform, or portions of the data 
that make up the platform, may be used by the Office of Air and 
Radiation in several contexts, including the development of rules 
related to the transport of air pollution and the National Ambient Air 
Quality Standards. The EPA is requesting comment on the 2018 Emissions 
Modeling Platform, including the emission inventories, the supporting 
data, and the methods used to develop and process the 2018 emission 
inventories. A docket has been established to facilitate public review 
of the data and to track comments.

DATES: Comments must be received on or before June 30, 2014. Please 
refer to SUPPLEMENTARY INFORMATION for additional information on 
submitting comments and on the provided data.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2013-0809, by one of the following methods:
     www.regulations.gov. Follow the on-line instructions for 
submitting comments.
     Fax: (202) 566-9744. Attention Docket ID No. EPA-HQ-OAR-
     Mail: EPA Docket Center, WJC West (Air Docket), Attention 
Docket ID No. EPA-HQ-OAR-2013-0809, U.S. Environmental Protection 
Agency, Mailcode: 2822T, 1200 Pennsylvania Ave. NW., Washington, DC 
20460. Please include a total of 2 copies.
     Hand Delivery: U.S. Environmental Protection Agency, WJC 
West (Air Docket), 1301 Constitution Avenue NW., Room 3334, Washington, 
DC 20004, Attention Docket ID No. EPA-HQ-OAR-2013-0809. Such deliveries 
are only accepted during the Docket's normal hours of operation, and 
special arrangements should be made for deliveries of boxed 
    Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-
2013-0809. The EPA's policy is that all comments received will be 
included in the public docket without change and may be made available 
online at www.regulations.gov, including any personal information 
provided, unless the comment includes information claimed to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Do not submit information that you 
consider to be CBI or otherwise protected through www.regulations.gov 
or email. The www.regulations.gov Web site is an ``anonymous access'' 
system, which means the EPA will not know your identity or contact 
information unless you provide it in the body of your comment. If you 
send an email comment directly to the EPA without going through 
www.regulations.gov, your email address will be automatically captured 
and included as part of the comment that is placed in the public docket 
and made available on the Internet. If you submit an electronic 
comment, the EPA recommends that you include your name and other 
contact information in the body of your comment and with any disk or 
CD-ROM you submit. If the EPA cannot read your comment due to technical 
difficulties and cannot contact you for clarification, the EPA may not 
be able to consider your comment. Electronic files should avoid the use 
of special characters, any form of encryption, and be free of any 
defects or viruses. For additional information about the EPA's public 
docket, visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
    Docket: All documents in the docket are listed in the 
www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in hard copy. 
Publicly available docket materials are available either electronically 
in www.regulations.gov or in hard copy at the Air and Radiation Docket 
and Information Center, EPA/DC, WJC West Building Room 3334, 1301 
Constitution Ave. NW., Washington, DC. The Public Reading Room is open 
from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal 
holidays. The telephone number for the Public Reading Room is (202) 
566-1744, and the telephone number for the Air Docket is (202) 566-

FOR FURTHER INFORMATION CONTACT: For questions on the 2018 Emissions 
Modeling Platform and on how to submit comments, contact Alison Eyth, 
Air Quality Assessment Division, Environmental Protection Agency, C339-
02, 109 T.W. Alexander Drive, Research Triangle Park, NC 27709; 
telephone number: (919) 541-2478; fax number: (919) 541-0684; email 
address: eyth.alison@epa.gov.

SUPPLEMENTARY INFORMATION: The EPA is requesting comment on the 2018 
platform emission inventories; supporting ancillary files used to 
allocate emissions temporally, spatially, and by species; and on the 
emissions modeling methods used to develop the 2018 emission 
inventories, including but not restricted to, the projection, control 
and closure data, activity data, and model input databases used to 
develop projected emission levels in 2018. Summaries of the emission 
inventories and data are provided to aid in the review of the data, but 
comments are sought on the actual inventories, model inputs, and data 
used to develop the projected 2018 emissions.

I. Additional Information on Submitting Comments

 A. What should I consider as I prepare my comments for EPA?

    1. Submitting CBI. Do not submit this information to the EPA 
through EDOCKET, www.regulations.gov, or email. Clearly mark the part 
or all of the information that you claim to be CBI. For CBI information 
in a disk or CD-ROM that you mail to the EPA docket office specified in 
the Instructions, mark the outside of the disk or CD-ROM as CBI and 
then identify electronically within the disk or CD-ROM the specific 
information that is claimed as CBI. Information so marked will not be 
disclosed except in accordance with procedures set forth in 40 CFR part 
2. In addition to one complete version of the comment that includes 
information claimed as CBI, a copy of the comment that does not contain 
the information claimed as CBI must be submitted for inclusion in the 
public docket.
    2. Tips for preparing your comments. When submitting comments, 
remember to:
    i. Identify the notification by docket number and other identifying 
information (subject heading, Federal Register date and page number).
    ii. Explain your comments, why you agree or disagree; suggest 
alternatives and substitute data that reflect your requested changes.
    iii. Describe any assumptions and provide any technical information 
and/or data that you used.
    iv. Provide specific examples to illustrate your concerns, and 
suggest alternatives.
    v. Explain your views as clearly as possible, avoiding the use of 
profanity or personal threats.

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    vi. Make sure to submit your comments by the comment period 
deadline identified.

B. Instructions for Submitting Comments and Alternative Data

    The EPA can most effectively use comments on data that provide 
specific alternative values to those in the EPA data sets, and for 
which accompanying documentation supports the alternative values. 
Commenters should provide the alternative data at a level of detail 
appropriate to the data set into which it will be incorporated, thereby 
including all key fields needed to substitute the old data with the 
new. For example, any data provided as an alternative to EPA's point 
source emissions data should include all key fields used to identify 
point source data such as facility, unit, release point, process, and 
pollutant, along with alternative emissions values. If a commenter were 
to provide a new set of county total emissions as an alternative to 
detailed point source emissions data, the EPA would be unable to use 
the new data. Commenters should also include documentation that 
describes methods for development of any alternative values and 
relevant references supporting the alternative approach.
    Any alternative emission inventory or ancillary data provided 
should be compatible with the formats used by the Sparse Matrix 
Operator Kernel Emissions (SMOKE) modeling system version 3.5.1, which 
is used by the EPA to process emission inventories into a format that 
can be used for air quality modeling. Formats are defined in the SMOKE 
Version 3.5.1 User's Manual available from http://www.smoke-model.org. 
Only the rows of data that have changed from those provided by the EPA 
should be included in the alternative data sets. Alternative data that 
are not an input to SMOKE, such as model input databases for mobile 
source models, should be provided in a format in which it could be 
directly input to the model.
    To comment on inventory projection methods, submit comments to the 
docket that describe an alternative approach to the existing methods, 
along with documentation describing why that method is an improvement 
over the existing method.

II. Information Available for Public Comment

    The 2018 Emissions Modeling Platform consists of emission 
inventories that represent projected emissions into the atmosphere of 
criteria and some hazardous air pollutants in the year 2018, additional 
ancillary data files that are used to convert the National Emissions 
Inventory (NEI) emissions into a form that can be used for air quality 
modeling, and methods used to prepare the air quality model inputs and 
to develop projections of emissions in the year 2018. The platform 
includes emission inventories for sources at specific locations called 
point sources; emissions from fire events; and county-level emissions 
of onroad mobile sources, nonroad mobile sources, and other nonpoint 
    In the modeling platform, emission sources are split into 
categories called modeling sectors. For example, location-specific 
point emission sources are split into peaking electric generating units 
(EGUs), other EGUs, oil and gas point sources, and other point sources. 
Nonpoint emission sources are split into agricultural ammonia sources, 
residential wood sources, oil and gas nonpoint sources, and other 
nonpoint sources.
    The 2018 emissions modeling platform is named for the year of the 
data that it represents. The emission inventories in the 2018 modeling 
platform have been developed using projection methods that are specific 
to the type of emission source. Emission projections for EGUs for 2018 
are developed using the Integrated Planning Model (IPM), which is 
further described below. Most non-EGU source emissions are projected 
based on the EPA's 2011 emissions modeling platform, which the EPA has 
also made available for public comment under a November 27, 2013, 
Federal Register notice titled 2011 Emissions Modeling Platform; 
Availability. The relevant 2011 data files are available in docket 
number EPA-HQ-OAR-2013-0743. Future emissions are projected from this 
base case either by running models to estimate emissions in the future 
year (i.e., EGUs, and onroad and nonroad mobile sources), or by 
adjusting the base year emissions according to the best estimate of 
changes expected to occur in the intervening years (i.e., non-EGU point 
and nonpoint sources).
    For some sectors, the same emissions are used in the base and 
future years, such as biogenic emissions, point source fire emissions, 
and Canadian emissions. For all other sectors, rules and specific legal 
obligations that go into effect in the intervening years, along with 
changes in activity for the sector, are considered when possible. 
Documentation of the methods used for each sector is provided in the 
Technical Support Document Preparation of Emissions Inventories for the 
Version 6.0, 2011 Emissions Modeling Platform, which can be found in 
the docket for this notice.
    In order to project future EGU emissions, the EPA uses the IPM. The 
National Electric Energy Data System (NEEDS) database contains the 
generation unit records used for the model plants that represent 
existing and planned/committed units in the EPA modeling applications 
of IPM. NEEDS includes basic geographic, operating, air emissions, and 
other data on these generating units and was completely updated for the 
EPA's new power sector modeling platform. The EGU emission projections 
included in this 2018 emissions modeling platform are reported in an 
air quality modeling-ready flat file taken from EPA Base Case v.5.13, 
developed using IPM. 2018 EGU emission projections in the flat file 
format, the corresponding NEEDS database, and user guides and 
documentation are available in the docket for this notice, and they are 
also available on the Internet at http://www.epa.gov/powersectormodeling.
    To project future emissions from onroad and nonroad mobile sources, 
the EPA uses MOVES and the National Mobile Inventory Model (NMIM), 
respectively. The 2018 projections were obtained by running these 
models to represent the year 2018 using year-specific information about 
fuel mixtures, activity data, and the impacts of national and state-
level rules and control programs. The mobile model input databases and 
future year activity data are provided at http://www.epa.gov/ttn/chief/emch/index.html#2011.
    For non-EGU point and nonpoint sources, projections of 2018 
emissions are developed by starting with the emissions inventories in 
the 2011 emissions modeling platform and applying adjustments that 
represent the impact of rules coming into effect in the years 2012 
through 2018, along with the impacts of planned shutdowns, the 
construction of new plants, specific information provided by states, 
and specific legal obligations, such as consent decrees resolving 
alleged environmental violations. Changes in activity are considered 
for sectors such as oil and gas, residential wood combustion, cement 
kilns, livestock, aircraft, commercial marine vessels and trains. Data 
files used to represent the changes due to national, state and local 
rules as well as other specific legal obligations, are provided along 
with summaries that quantify the emission changes resulting from each 
program at a state and national-level.
    The 2018 Emissions Modeling Platform also includes 2006 emissions

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inventories for Canada and projected 2018 emissions inventories for 
Mexico, along with ancillary data files used to allocate annual 
emissions to the hourly, gridded emissions of chemical species used by 
an air quality model (AQM). The types of ancillary data files include 
temporal profiles that allocate annual and monthly emissions down to 
days and hours, spatial surrogates that allocate county-level emissions 
onto the grid cells used by an AQM, and speciation profiles that 
allocate the pollutants in the NEI to the chemical species used by an 
AQM. In addition, there are temporal, spatial, and speciation cross-
reference files that map the emission sources in the emission 
inventories to the appropriate profiles based on their location, 
emissions source classification code (SCC), and in some cases the 
specific facility or unit. With the exception of some speciation 
profiles, the ancillary data files are unchanged from the data files 
associated with the 2011 emissions modeling platform. The EPA provided 
an opportunity for comment on the data files for the 2011 platform in a 
notice published on November 27, 2013, and those files are available in 
docket number EPA-HQ-OAR-2013-0743.
    The 2018 emissions modeling platform, or portions of the data that 
make up the platform, may be used by the Office of Air and Radiation in 
several contexts including the development of rules related to the 
transport of air pollution and the National Ambient Air Quality 
Standards. Air quality modeling results that are based on the outputs 
of the emissions modeling platform are typically used in support of 
Regulatory Impact Analyses (RIAs) and sometimes support other aspects 
of rulemaking efforts.
    The EPA has placed key information related to the 2018 Emissions 
Modeling Platform into the electronic docket available at 
www.regulations.gov. However, many of the detailed data files are too 
large to be directly uploaded into the electronic docket and/or are not 
in formats accepted by that docket. Therefore, the information placed 
in the electronic docket, associated detailed data, and summaries to 
help with interpretation of the data are available for public review on 
the EPA's Clearinghouse for Inventories and Emissions Factors (CHIEF) 
Web site at http://www.epa.gov/ttn/chief/emch/index.html#2011.
    The emissions inventories, along with many of the ancillary files, 
are provided in the form of flat files that can be input to SMOKE. Flat 
files are comma-separated value style text files with columns and rows 
that can be loaded into spreadsheet or database software. The columns 
of interest in the emission inventory files are specified in each 
subsection below. The EPA requests comment on the following components 
of the 2018 emissions modeling platform data:
     Emissions values and supporting data for EGUs. The EPA 
requests comment on the IPM version 5.13 input assumptions, NEEDS 
database, 2018 unit-level parsed files, 2018 flat file inputs and 
outputs, and cross references and matching between IPM and NEI. The EPA 
also requests comment on the specific units that are expected to be 
used as peaking units in the future year and on the nature of the 
expected 2018 emissions from those units.
     Emission values for non-EGU sources. The EPA requests 
comment on the criteria air pollutant (CAP) 2018 emission projections 
in the modeling inventories, with the focus on ozone and particulate 
matter precursors such as nitrogen oxides (NOX), sulfur 
dioxide (SO2), particulate matter less than 2.5 micrometers 
(PM2.5), particulate matter less than 10 micrometers 
(PM10), volatile organic compounds (VOC), and ammonia 
(NH3). The EPA will also accept comments on 2018 projections 
of hazardous air pollutants (HAPs), as they are included in the outputs 
of models used to develop 2018 emission projections, but HAPs are not 
the focus of this effort. The annual emissions values are located in 
the ANN--VALUE column of emission inventory files in the Flat File 2010 
(FF10) format. Some emission inventories (e.g., nonroad) may also have 
values filled in to the monthly value columns (e.g., JAN--VALUE, FEB--
VALUE, . . ., DEC--VALUE). The EPA requests comment on both the annual 
and monthly emissions values, where applicable. Summaries of emissions 
by state and county are provided to aid in the review of emissions 
     Model inputs and activity data used to develop mobile 
source emission inventories. The EPA requests comment on the mobile 
source model input data used to develop the projected future mobile 
source emission inventories. These include both the databases used to 
create emission factors and the vehicle miles traveled and vehicle 
population activity data used to compute the emissions. Of particular 
interest are county total vehicle miles traveled, the mixture of 
vehicle types in 2018, and changes to the inspection and maintenance 
programs. Alternative activity data may be provided in the form of 
MOVES county databases or in SMOKE FF10 activity data format.
     Projection data and methods. The EPA seeks comment on the 
data used to project point and nonpoint source emissions from 2011 to 
2018, and on the methods and assumptions used to implement the 
projections. In this context, nonpoint source emissions are inclusive 
of commercial marine vessel, railroad, and other nonpoint emissions. In 
particular, the EPA seeks comment on its assumptions regarding the 
manner in which specific consent decrees and state- or locality-
specific control programs will be implemented. Summaries are provided 
to illustrate the EPA's current assumptions regarding the 
implementation of consent decrees and other programs.
     Existing control techniques. The emission inventories 
include information on emissions control techniques listed in terms of 
control codes submitted to the EIS. These are listed in the CONTROL--
IDS and CONTROL--MEASURES columns in the emission inventory flat files, 
with levels of reduction in the ANN--PCT--RED column. Projection of 
non-EGU point source emissions to future years is dependent on this 
information. The EPA seeks comment on whether information on existing 
controls given in the inventory flat files is incomplete or erroneous. 
The flat files must be consulted for details of control techniques by 
     Emissions modeling methods. The EPA is using the SMOKE 
version 3.5.1 to prepare data for air quality modeling. The EPA 
requests comment on the methods by which SMOKE is used to develop air 
quality model-ready emissions, as illustrated in the scripts provided 
with the modeling platform and as described in the Technical Support 
Document Preparation of Emissions Inventories for the Version 6.0, 2011 
Emissions Modeling Platform.
     Temporal allocation. Annual emission inventories must be 
allocated to hourly values prior to air quality modeling. This may be 
done with temporal profiles in several steps, such as annual-to-month, 
month-to-day, and day-to-hour. The exact method used depends on the 
type of emissions being processed. The EPA seeks comment on the 
allocation of the emission inventories to month, day, and hour for all 
types of emission processes. In particular, the EPA seeks information 
that could help improve the temporal allocation in 2018 of emissions 
from EGUs, nonroad mobile sources, residential wood combustion sources, 
and the temporal allocation of vehicle miles traveled needed to model 
onroad sources. The EPA seeks local- and region-specific data that can 
be used to

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improve the temporal allocation of emissions data.
     Spatial surrogates. Spatial surrogates are used to 
allocate county-level emissions to the grid cells used for air quality 
modeling. The EPA requests comment on the spatial surrogates used in 
the 2018 Emissions Modeling Platform. The same spatial surrogates are 
used in the base and future years.
     Chemical speciation. Prior to air quality modeling, the 
pollutants in the emission inventories must be converted into the 
chemical species used by the air quality model using speciation 
profiles. The speciation profiles in the 2018 emissions modeling 
platform are consistent with version 4.3 of the SPECIATE database. The 
EPA requests comment on the speciation profiles used in the 2018 
modeling platform, as well as any information that could help improve 
the speciation of oil and gas emissions in both the eastern and western 
United States in 2018. Oil and gas speciation information, along with 
VOC to TOG adjustment factors that are used to compute methane 
emissions, would be of the most use at the county or oil/gas basin 
level of detail and also for each distinct process at oil and gas 
drilling/production facilities (e.g., glycol dehydrators).
    To aid in the interpretation of the provided data files and how 
they relate to the aspects of the data on which the EPA is requesting 
comment, the EPA has provided in the docket a document describing the 
information included in the data files.

    Dated: January 8, 2014.
Mary E. Henigin,
Director, Office of Air Quality Planning and Standards.
[FR Doc. 2014-00564 Filed 1-13-14; 8:45 am]