United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park, NC 27711
EPA-454/R-99-006
April 1999
Air
Emissions Inventory Guidance for
Implementation of Ozone and Particulate Matter
National Ambient Air Quality Standards
(NAAQS) and Regional Haze Regulations
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Emissions Inventory Guidance for
Implementation of Ozone and Particulate Matter
National Ambient Air Quality Standards
(NAAQS) and Regional Haze Regulations
Issued By:
Emission Factor and Inventory Group
Emissions, Monitoring and Analysis Division
Office of Air Quality Planning and Standards
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
v. s Environmental Protection Agency
KfrV'°n 5, Library (PL-12J)
77 West Jackson Boulevard, 12tn NOOf
Chicago, IL 60604-3590
April 1999
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DISCLAIMER
THIS DOCUMENT HAS BEEN REVIEWED BY THE OFFICE OF AIR QUALITY PLANNING AND
STANDARDS. MENTION OF TRADE NAMES OR COMMERCIAL PRODUCTS DOES NOT
CONSTITUTE ENDORSEMENT OR RECOMMENDATION FOR USE.
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CONTENTS
Page
DISCLAIMER "
LIST OF TABLES v
ACRONYMS AND ABBREVIATIONS vi
SECTION 1.0
OVERVIEW 1
1.1 PURPOSE 1
1.2 RELATIONSHIP TO EMISSION INVENTORY IMPROVEMENT PROGRAM (EHP)
GUIDANCE 1
1.3 RELATIONSHIP TO THE CONSOLIDATED EMISSIONS REPORTING RULE (CERR) . 2
1.4 IMPLEMENTATION 2
1.5 SUMMARY OF DOCUMENT CONTENTS 3
SECTION 2.0
REGULATORY REQUIREMENTS, DEFINITIONS, AND SUBMITTAL DATES 5
2.1 STATUTORY AND REGULATORY REQUIREMENTS 5
2.2 TYPES OF INVENTORIES 5
2.3 SPECIFICATION OF BASE YEAR 6
2.3.1 Ozone 6
2.3.2 Paniculate Matter 7
2.3.3 Regional Haze 7
2.4 INVENTORY PREPARATION PLAN 7
2.5 INVENTORY APPROVAL 9
SECTION 3.0
EMISSION INVENTORY REQUIREMENTS 11
3.1 IDENTIFICATION OF INVENTORY USES 11
3.2 COMPONENTS OF THE BASE YEAR AND 3-YEAR CYCLE INVENTORIES 12
3.2.1 Pollutants and Pollutant Precursors to Be Inventoried 12
3.2.2 Identification of Sources and Source Categories to Be Inventoried 13
3.2.3 Geographic Coverage 14
3.2.4 Temporal Basis of Emissions 15
3.2.5 Rule Effectiveness and Rule Penetration 15
3.3 MODELING INVENTORIES 16
3.3.1 Temporal Allocation Procedures 17
3.3.1.1 Point Sources 17
3.3.1.2 Area and Mobile Sources 19
3.3.2 Spatial Allocation Procedures 22
3.3.2.1 Point Sources 22
3.3.2.2 Area and Mobile Sources 23
3.3.3 Speciation Procedures 27
111
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CONTENTS (continued)
Page
SECTION 4.0
DATA REPORTING REQUIREMENTS 31
4.1 POINT SOURCES 31
4.2 AREA SOURCES 31
4.3 NONROAD MOBILE SOURCES 32
4.4 ONROAD MOBILE SOURCES 32
4.5 BIOGENIC AND GEOGENIC SOURCES 32
4.6 DEVELOPMENT OF COMPREHENSIVE EMISSION DATA BASE AT EPA 33
4.7 ELECTRONIC DATA TRANSFER REQUIREMENTS 33
4.7.1 Overview 33
4.7.2 EPA NET Input Format 34
4.7.3 AIRS Format 34
4.7.4 EIIP/EDI Format 35
4.7.5 Direct Source Reporting 35
4.8 SUMMARY DATA REPORTING 36
SECTION 5.0
EMISSION INVENTORY DEVELOPMENT 39
5.1 AVAILABLE GUIDANCE 39
5.2 NATIONAL EMISSION TRENDS INVENTORY 39
5.3 POINT SOURCES 40
5.4 AREA SOURCES 41
5.5 MOBILE SOURCES 46
5.5.1 Onroad Mobile Sources 47
5.5.2 Nonroad Mobile Sources 51
5.6 BIOGENIC AND GEOGENIC SOURCES 54
5.6.1 Biogenic Sources 54
5.6.2 Geogenic and Other Natural Sources 55
SECTION 6.0
QUALITY ASSURANCE/DOCUMENTATION OF THE INVENTORY 57
6.1 QUALITY ASSURANCE 57
6.2 DOCUMENTATION OF THE INVENTORY 58
SECTION 7.0
REFERENCES 63
APPENDIX A
DRAFT CONSOLIDATED EMISSIONS REPORTING (CER) RULE A-l
IV
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LIST OF TABLES
Table Page
3.3-1. Default Hourly VMT Fractional Profile 22
3.3-2. Stack Parameter Ranges Used in the Initial Screening 23
3.3-3. Area Source Spatial Surrogates 25
3.3-4. Four-digit Area Source Category Codes and the Predominant Area Source Spatial Surrogate . 26
4.8-1. Statewide Ozone Precursor Emissions by Source Sector 36
4.8-2. Statewide PM25 and Precursor Emissions by Source Sector 37
5.3-1. Point Sources of Emissions 42
5.4-1. Area Sources of Emissions 44
5.4-2. Crustal Sources of Emissions 46
5.5-1. Mobile Sources of Emissions 47
5.5-2. PART5 Vehicle Classes 51
5.6-1. Natural Source Categories and Pollutants Emitted 54
6.2-1. Outline for Format/Contents for SIP Emission Inventory Reports 60
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ACRONYMS AND ABBREVIATIONS
AFS
AIRS
ALAPCO
AMS
ANSI
BEIS-2
BIOME
BSFC
CAA
CARB
CASAC
CB-IV
CEMS
CERR
CG
CHIEF
CNG
CO
EC
EDI
EDR
EFIG
EIIP
EKMA
EMS
EPA
FAA
FHWA
FTP
GTM
GCVTC
HAP
HCs
HDDV
HDGV
HONO
HPMS
1C
I/M
IPP
LDDT
LDDV
LDGT
LDGV
LPG
LTOs
AIRS/Facility Subsystem
Aerometric Information Retrieval System
Association of Local Air Pollution Control Officials
Area and Mobile Subsystem
American National Standards Institute
Biogenic Emissions Inventory System-2
Biogenic Model for Emissions
brake specific fuel consumption
Clean Air Act
California Air Resources Board
Clean Air Act Scientific Advisory Committee
Carbon Bond IV
Continuous emission monitoring system
Consolidated Emissions Reporting Rule
cloud-to-ground
Clearing House for Inventories and Emission Factors
compressed natural gas
carbon monoxide
elemental carbon
Electronic Data Interchange
electronic data reporting
Emission Factor and Inventory Group
Emission Inventory Improvement Program
Empirical Kinetic Modeling Approach
Emission Modeling System
Environmental Protection Agency
Federal Aviation Administration
Federal Highway Administration
file transfer protocol
gross ton miles
Grand Canyon Visibility Transport Commission
hazardous air pollutant
hydrocarbons
heavy-duty diesel vehicle
heavy-duty gasoline vehicle
gaseous nitrous acid
Highway Performance Monitoring System
intra-cloud
inspection and maintenance
Inventory Preparation Plan
light-duty diesel truck
light-duty diesel vehicle
light-duty gasoline truck
light-duty gasoline vehicle
liquid petroleum gas
landing and takeoffs
VI
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ACRONYMS AND ABBREVIATIONS (continued)
MoVEM Motor Vehicle Emissions Estimates Model
NAAQS national ambient air quality standard
NAICS North American Industry Classification System
NAPAP National Acid Precipitation Assessment Program
NET National Emission Trends
NH3 ammonia
NMHC nonmethane hydrocarbons
NMOG nonmethane organic gases
NO nitric oxide
NO2 nitrogen dioxide
NOX oxides of nitrogen
NTTAA National Technology Transfer and Advancement Act
OAQPS Office of Air Quality Planning and Standards
OC organic carbon
OMB Office of Management and Budget
OMS Office of Mobile Sources
OTAG Ozone Transport Assessment Group
OTC Ozone Transport Commission
PCBEIS-2.2 Personal Computer version of the Biogenic Emission Inventory System-2.2
PCC process category code
PM paniculate matter
PM10 particles with an aerodynamic diameter less than or equal to a nominal
10 micrometers
PM: 5 particles with an aerodynamic diameter less than or equal to a nominal
2.5 micrometers
QA quality assurance
QC quality control
RADM Regional Acid Deposition Model
RE rule effectiveness
ROG reactive organic gas
ROM Regional Oxidant Model
RP rule penetration
RVP Reid vapor pressure
SAEWG Standing Air Emissions Work Group
SAPRC California Statewide Air Pollution Research Center
SAQM SARMAP Air Quality Model
SARMAP San Joaquin Valley Air Quality Study/Atmospheric Utilities Signatures, Predictions
and Experiments Regional Modeling Adaption Project
SCC source classification code
SIC Standard Industrial Classification
SIP State Implementation Plan
SO2 sulfur dioxide
SO4 sulfate
SOV oxides of sulfur
vn
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ACRONYMS AND ABBREVIATIONS (continued)
STAPPA
TAFF
TCA
TDM
TEA-21
THC
TOG
TTN
UAM
UMRA
U.S.
UTM
VMT
voc
State and Territorial Air Pollution Program Administrators
Temporal Allocation Factor File
1,1,1 -trichloroethane
travel demand model
Transportation Equity Act for the 21st Century
total hydrocarbons
total organic gases
Technology Transfer Network
Urban Airshed Model
Unfunded Mandates Reform Act
United States
universal transverse mercator
vehicle miles traveled
volatile organic compound(s)
Vlll
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SECTION 1.0
OVERVIEW
1.1 PURPOSE
The purpose of this guidance document is to define required elements of emission inventories
necessary to meet State Implementation Plan (SIP) requirements for complying with the 8-hour ozone
national ambient air quality standard (NAAQS), the revised particulate matter NAAQS and the regional
haze regulations. For the particulate matter NAAQS, the emphasis in this guidance is on particulate
matter with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers (PM25). However.
the earlier PM10 (particulate matter with an aerodynamic diameter less than or equal to a nominal
10 micrometers) NAAQS is still in effect and, therefore, States should continue to inventory PM10 as
well. The required elements include those for compiling and reporting the emission inventories to the
United States (U.S.) Environmental Protection Agency (EPA).
For the 8-hour ozone NAAQS, this guidance applies to all nonattainment area classifications except
"transitional." Transitional ozone areas are nonattainment areas that may be able to demonstrate
attainment of the 8-hour NAAQS through actions intended to meet the 1-hour NAAQS. An example
would be areas in the East that can demonstrate attainment of the 8-hour NAAQS as a result of actions
taken in response to the oxides of nitrogen (NOX) SIP call. Emission inventory guidance for these
transitional areas is included in Implementation Guidance for the Revised Ozone and Particulate Matter
(PM) National Ambient Air Quality- Standards (NAAQS) and the Regional Haze Program,1 Section 3
"SIP Requirements for Transitional Areas," Subsection b "Emission Inventory, Modeling and Attainment
Demonstration."
Ozone, regional haze, and a significant portion of PM25 are produced in the air by the combination
of pollutants ("precursor pollutants") from many of the same local emission sources. In addition, studies
have identified the long-range transport of pollutants as contributing to ambient air violations and
visibility impairment. Therefore, this guidance document emphasizes the importance of preparing a
single, statewide inventory for all pollutant emissions that contribute to the formation of ozone, PM-, 5,
and regional haze.
1.2 RELATIONSHIP TO EMISSION INVENTORY IMPROVEMENT PROGRAM
(EIIP) GUIDANCE
This document is a guide for State and local agencies for the requirements for submitting their
emission inventories for the 8-hour ozone and PM2 5 NAAQS, and for the regional haze program. It is
not a procedures document covering the methods for compiling and documenting emissions inventories.
The Emission Inventory Improvement Program (EIIP) has been and will continue to develop the
procedures for compiling and documenting emission inventories for point, area, nonroad mobile, onroad
mobile, biogenic, and geogenic source categories. Thus, the EIIP guidance compliments this
requirements document.
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The goal of EIIP is to provide cost-effective, reliable inventories by (1) improving the quality of
emissions information; and (2) developing systems for collecting, calculating, and reporting emissions
data. The goal is achieved by developing a set of "preferred and alternative methods" for all inventory
associated tasks. This standardization improves the consistency of collected data and results in increased
usefulness of emissions information. The EIIP will reach its goal through development of:
• Preferred methods for collecting data and calculating emissions;
• Improved reporting systems;
• Procedures for quality control; and
• More consistent guidance.
The EIIP is a jointly sponsored effort of the State and Territorial Air Pollution Program
Administrators/Association of Local Air Pollution Control Officials (STAPPA/ALAPCO) and EPA, and
is an outgrowth of the Standing Air Emissions Work Group (SAEWG). Funding is provided by
State/local agencies through the federal 105 grant programs. The EIIP Steering Committee and technical
committees are composed of State, local, industry, and EPA representatives. The EITP maintains a web
site which provides the documents prepared by EIIP as well as periodic updates on EIIP activities and
products. The web site address is: http://www.epa.gov/oar/oaqps/eiip/. The documents prepared by the
EIIP should, where appropriate, be used instead of existing emission inventory procedures guidance.
1.3 RELATIONSHIP TO THE CONSOLIDATED EMISSIONS REPORTING RULE
(CERR)
The EPA is preparing the Consolidated Emissions Reporting Rule (CERR) to improve and simplify
the reporting of emission inventory information. A draft of the CERR is provided in Appendix A of this
document. The preparation of the CERR will assist State and local agencies to:
• Determine and integrate the various emissions reporting requirements;
• Improve reporting efficiency; and
• Provide flexibility for data gathering and reporting.
Numerous State and local agencies requested that EPA consolidate its various air emissions
reporting requirements. This should increase the efficiency of the emission inventory program and
provide more consistent and uniform data. Consolidating reporting requirements will enable agencies to
better explain to program managers and the public the necessity for a consistent inventory program. This
action, while including new data collection requirements for PM25, its precursors, and hazardous air
pollutants (HAPs), reduces the reporting requirements for other criteria pollutants.
This document incorporates the 8-hour ozone, PM25, and regional haze emission inventory
requirements of the draft rule presented in Appendix A. This guidance document and the CERR were
developed in parallel, and this guidance document is being released before the CERR is published in its
final form. While the CERR is undergoing the rulemaking process, EPA believes that there is sufficient
existing statutory authority to implement the provisions contained in this guidance document. If there are
conflicts between this guidance document and the final rule, the final rule will take precedence.
1.4 IMPLEMENTATION
Section 2.3 of this document provides details of SIP inventory implementation schedules.
Implementation of the 8-hour ozone NAAQS began after it was finalized in July 1997. Similarly,
implementation of the regional haze regulations will begin after they are finalized in the spring of 1999.
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The implementation of the PM,, NAAQS will not occur until after the Clean Air Act Scientific
Advisory Committee (CASAC) completes its review of the standard in 2002. However, because many of
the same sources produce emissions that contribute to ozone and PM25 formation and visibility
impairment. EPA encourages States to coordinate emission inventory planning and development efforts
for ozone, regional haze, and PM2 5 as they develop their required inventories for ozone. EPA believes
that the States should take advantage of the opportunity to produce a PM emission inventory while they
are collecting data and preparing their ozone precursor inventory. Coordination of emission inventory
planning and development efforts will help to reduce the burden associated with preparing separate
inventories, improve the accuracy of emission inventories through the application of consistent methods,
improve regional modeling studies, and improve coordination of control strategy development.
1.5 SUMMARY OF DOCUMENT CONTENTS
Section 2 of this document summarizes the regulatory requirements for emission inventories for the
8-hour ozone and PM, 5 NAAQS, and the regional haze regulations. This section also provides a brief
overview of the types of inventories that States will need to prepare for their SIPs, specifies the year for
which the base year inventories are to be prepared, and provides a time line illustrating the relationship
between the schedules for submittal of emission inventories and other SIP milestones. Section 2.0 also
discusses the emission inventory planning and approval process.
Section 3 identifies and explains the key requirements for ozone, PM. and regional haze SIP
emission inventories. The topics covered include requirements for the inventory base year and periodic
inventories; uses of the inventories; defining the pollutants and pollutant precursors, and sources and
source categories, to be inventoried; geographic coverage of inventories; temporal basis of emissions;
application of rule effectiveness (RE) and rule penetration (RP); and modeling inventories. For modeling
inventories, this section explains the procedures by which emissions in a completed base year or
projection year inventory are temporally allocated, spatially allocated, and speciated for use in a
photochemical grid model. By explaining these procedures, it is anticipated that State and local agencies
will be able to provide more complete and accurate data to increase the accuracy of the procedures.
Section 4 provides brief definitions and data element reporting requirements for stationary point and
area, nonroad mobile, onroad mobile, biogenic, and geogenic emission sources. This section also
specifies data reporting and electronic data transfer requirements, and discusses how the emission
inventories submitted by State and local agencies are compiled into a comprehensive emission data base
at EPA.
Section 5 addresses emission inventory development requirements for the base year and periodic
emission inventories. This section provides an overview of the types of emission sources and pollutants
expected to be considered for inclusion in an inventory, and cross-references existing emission inventory
development procedures by source category and pollutant where available. Section 5 also emphasizes the
importance for State and local agencies to collect the best activity data available for their inventories.
The EPA recognizes that emission factors are either currently not available or have higher uncertainty for
some pollutants [e.g., PM,5 and ammonia (NH3)], and is conducting ongoing research to develop new
and improved emission factors. Therefore, because it is difficult to collect high-quality activity data
retrospectively, emphasis should be placed on collecting good activity data for the base year inventory.
As emission factors are developed or improved, the factors can be applied to the activity data to improve
emission estimates.
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The final section of this document, Section 6, discusses the importance of including quality
assurance (QA) and quality control (QC) procedures in the inventory planning and development process,
and the importance of preparing sound documentation for the inventories.
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SECTION 2.0
REGULATORY REQUIREMENTS, DEFINITIONS,
AND SUBMITTAL DATES
This section reviews the Clean Air Act (CAA) provisions and associated regulations that require
States to compile and submit air pollution emission estimates to EPA. It also reviews inventory types,
emission inventory submittal dates, Inventory Preparation Plans (IPPs), and the EPA approval process.
2.1 STATUTORY AND REGULATORY REQUIREMENTS
EPA interprets Section 110(a)(2)(F) of the CAA (codified in 40 CFR 51 Subpart Q) as requiring
SIPs to provide for the reporting of criteria air pollutants for all areas under the general SIP requirements
of section 110. In addition, EPA interprets section 172(c)(3) as providing the Administrator with
discretionary authority to require other emissions data as deemed necessary for SIP development in
nonattainment areas to attain the NAAQS. This statutory authority provides a basis for requiring SIPs to
provide for a periodic inventory of PM10 emissions for PMj0 nonattainment areas, PM;,5 emissions and
emissions of the PM, 5 precursors NH3, NOX, and oxides of sulfur (SOJ. Section 169(A) provides
authority for emission inventories to be required in SIPs developed to protect visibility in Federal Class I
areas.
2.2 TYPES OF INVENTORIES
For the purpose of developing SIPs to demonstrate compliance with the 8-hour ozone NAAQS,
PM25 NAAQS, and regional haze rule, there are three basic kinds of inventories that are necessary.
These three are the base year, periodic, and modeling inventories. Because of the increasingly regional
nature of air quality analysis and planning, all three types of inventories should be prepared on a
statewide basis. The base year inventory is the primary inventory from which the other two inventories
are derived. Thus, all inventories should be consistent with data provided in the base year inventory.
The CAA calls for States to ensure that the base year inventory is comprehensive, accurate, and current
for all actual emissions. The inventory should include emissions estimates from stationary point and area
sources (from both anthropogenic and biogenic origin), onroad mobile sources, and nonroad mobile
sources.
Every 3 years after the base year inventory is developed, States are required to develop periodic
inventories (in the future to be called the 3-year cycle inventory) based on actual emissions. This
inventory is used to measure overall emission reduction trends and meet information requests from the
general public. These inventories will be important to future modeling studies and emissions trading
programs.
Modeling inventories are required for developing the attainment demonstration. A modeling
inventory, defined as an inventory that will be processed through an "emissions preprocessor," is only
prepared for a specific modeling application. The inventory requirements specified in this guidance will
support modeling, but do not require a modeling inventory per se. Modeling inventories are based on
either allowable or actual emissions depending on the purpose of the modeling. For example, modeling
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inventories are based on the actual emissions for model performance evaluation. For control measure
evaluations and the attainment demonstration, the modeling inventory is based on actual emissions for
the base year and projected allowable emissions for the attainment year.
As an alternative to using allowable emissions for projections for the 8-hour ozone standard, current
EPA policy allows the use of actual emissions in certain circumstances. For sources or source categories
that are currently subject to a regulation, and where the State does not anticipate subjecting the source(s)
to additional regulation, the projected emissions may be based on actual emissions. In addition, for
sources or source categories that are currently unregulated and are not expected to be subject to future
regulations, the projected emissions may be based on actual emissions. For all other sources (i.e.,
sources that are expected to be subject to additional regulation), the projections should be based on the
new allowable emissions (including RE). Where a State chooses to project emissions using a different
approach than described above, the State should get the approval of the appropriate EPA Regional Office
before proceeding. In addition, the State should provide complete documentation of the approach and
documentation and technical justification of any assumptions. For PM10 and PM25, current EPA policy
only permits the use of allowable emissions in projections to future years. EPA is reviewing the policy
for all pollutants to determine if more realistic projected emission estimates can be obtained.
Previously, modeling inventories were only specifically required for areas performing
photochemical grid-based modeling to demonstrate attainment of the 1-hour ozone NAAQS; however,
recent events have shown that most States also need access to emissions data outside their borders.
Regional approaches such as the Ozone Transport Assessment Group (OTAG), the Ozone Transport
Commission's (OTC) NOX baseline study, and the Grand Canyon Visibility Transport Commission's
(GCVTC) study have emphasized the need for regional (multi-State) emission inventories. Regional
modeling is expected to become even more prevalent as areas develop attainment plans for the 8-hour
average ozone and the PM,5 NAAQS, and to develop plans and demonstrate progress toward meeting
regional haze visibility goals. Thus, needs for multi-State inventories to support grid-based modeling are
increasing.
Countywide emission estimates are needed for all counties. Where a State is unable to provide this
information, EPA's National Emission Trends (NET) inventory can be used for regional analyses. States
that are performing modeling analyses generally have to make emission estimates for more than just a
nonattainment area. In the absence of State-prepared emissions data, the NET inventory may be used.
Without additional State scrutiny, however, the risk of incorrect air quality estimates is increased.
2.3 SPECIFICATION OF BASE YEAR
This section specifies the base year for the emission inventory that States should use in the
development of their SIPs for ozone, PM, and regional haze. In each case, the base year was determined
by considering when the SIP was due, and the time needed to prepare the SIP, perform the modeling
studies, and prepare the emission inventory. In selection of the base year, consideration was also given to
the 3-year frequency of emission inventory preparation in the CERR, as well as, conserving State
resources by using a single inventory year for multiple applications.
2.3.1 Ozone
States are strongly encouraged to select 1999 as the base year for the emission inventory for the
8-hour ozone NAAQS. That is, EPA suggests that the base year inventory for the ozone NAAQS should
be representative of calendar year 1999. However, this guidance permits a State to select any year from
1996 to 1999 as its base year. If this inventory will be used as a part of a regionwide modeling domain,
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then all of the States in that domain should agree to use the same base year. The appropriate EPA
Regional Office(s) should be involved in selection of the base year. The State should detail in its EPP
(see section 2.4 for more information on IPPs) the base year selected, or specify the process for selecting
a base year if a regionwide domain is necessary.
2.3.2 Particulate Matter
A base year for the PM25 NAAQS inventory and a submittal date for the inventory cannot be
specified until the NAAQS review is complete in 2002. However, it is important that States should begin
in 1999 to identify and characterize their sources of PM and PM precursors. Some of the PM precursors
will already be inventoried as part of the ozone inventory (VOC and NOJ and the acid rain reporting
provisions (SOJ. The only additional requirement for the States is that they include PM2 5 and PM10 and
the precursor NH, as they characterize their sources. To ensure progress toward developing a PM
inventory, States, for example, should estimate the PM25 and PM10 emissions from all of their point
sources at the same time they estimate ozone precursor emissions. If the NAAQS review upholds the
current PM: 5 standard. States with monitoring data available for designations in 2002 to 2005 will need
to have a base year of 2002 for their emission inventory.
2.3.3 Regional Haze
The base year for the emission inventory for developing regional haze control strategy SEPs will be
contingent on the final regional haze rule, but is likely to be the same as the base year for developing
nonattainment area SIPs under the PM25 NAAQS. Therefore, as with PM25, States should begin in 1999
to identify and characterize their sources. Again, to ensure progress toward developing a regional haze
inventory, the States may want to do this as they estimate ozone precursor emissions.
The Transportation Equity Act for the 21st Century (TEA-21), passed in June 1997, includes revised
time lines for regional haze and PM25 SIP submittals. PM25 nonattainment areas are to be designated in
the 2002 to 2005 time frame, and PM2 5 SIPs would be due 3 years later, in the 2005 to 2008 period. For
these same geographic areas, regional haze SIPs would be due at the same time. The TEA-21 also
requires regional haze SIPs to be submitted within 1 year for the geographic areas designated attainment
or unclassifiable for PM25. These regional haze SIPs would be due in the 2003 to 2006 time frame.
EPA is considering the possibility of an optional approach whereby States could commit to
participation in future regional planning efforts and have coordinated deadlines for regional haze control
strategy SIPs covering the geographic areas designated nonattainment, attainment, and unclassifiable for
PM25. States committing to regional planning efforts may need to conduct preliminary technical analyses
characterizing interstate pollutant transport. To perform such analyses, which would precede more
detailed analyses for the development of control strategies, the States may need to use the 1999 base year
inventory.
2.4 INVENTORY PREPARATION PLAN
IPPs are used as a planning tool to guide inventory preparation and ensure that emission estimates
are of high quality and are consistent with CAA requirements. IPPs provide States with the opportunity
to tell their EPA Regional Office how they plan to compile their required inventories and allow EPA to
provide feedback to avoid having States use approaches that are inconsistent. Because EPA has
attempted to be as flexible as possible on how it allows States to meet the CAA inventory requirements,
EPA is now requiring States to submit detailed IPPs which describe how the inventory is developed, what
it includes, and what assumptions are being made. States should prepare and submit these IPPs for the
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8-hour ozone and PM NAAQS and the regional haze program statewide emission inventories. States that
prepared earlier IPPs for the 1-hour ozone or the PM10 NAAQS can use these IPPs as the starting point
for the 8-hour ozone, PM;5, and regional haze IPPs. IPPs can also serve as standard operating procedures
for the States for future inventory preparation and as documentation of inventory procedures to other
neighboring States in regional planning efforts.
The IPPs should include descriptions of inventory objectives and general procedures. One of the
first steps in developing the IPP is to define the purpose and scope of the inventory. This includes
identifying items such as base year for the inventory, the pollutants to be inventoried, the emissions
sources and source categories, the geographical boundaries of the inventory, the spatial and temporal
scales of the emissions, and the application of controls and regulations, including RE and RP. The IPPs
for inventories that report VOC emissions should include the State's definition of VOC and what species
are included. The IPPs should also contain a schedule or time line for when the States plan to submit
their inventories or inventory components to EPA. This schedule/time line should also show how the
inventory preparation or review process will mesh with the application of these inventories in
atmospheric modeling. If the State plans to submit an inventory in components (e.g., point sources, area
sources, etc.), the IPP should so indicate, along with their submittal dates by component. Final submittal
dates should be consistent with the ultimate inventory dates required by EPA (see section 2.3).
The IPP should contain the following sections, including separate sections to address the point, area,
nonroad mobile, onroad mobile, and biogenic portions of the inventory:
• Introduction
This section includes items such as: a description of the inventory objectives, including how this
IPP is structured, what it contains, who is responsible for the inventory, and who is compiling it; the
geographic area covered by the inventory; the base year of the inventory (see section 2.3); the
pollutants included in the inventory (see section 3.2.1); and the temporal resolution of the inventory.
• Point Source Inventory
Topics to be discussed in this section include: how sources are identified and located; what data
collection methods are used; the basis for activity data and emissions estimates; how control
efficiencies are identified and applied; whether RE and RP are applied and their values (see section
3.2.5); and how temporally resolved emissions are prepared and supplied (see section 3.2.4).
• Area Source Inventory
This section identifies what source categories are included in the inventory (see section 3.2.2), how
emissions are estimated, how data are identified and collected, whether RE and RP are applied and
their values (see section 3.2.5), how emissions are temporally and spatially resolved and supplied
(see sections 3.2.4 and 3.3), and how double-counting of emissions is avoided.
• Nonroad Mobile Source Inventory
This section includes details on what source categories are included in the inventory (see section
3.2.2), how emissions are estimated, how data are identified and collected, and how emissions are
temporally and spatially resolved and supplied (see sections 3.2.4 and 3.3).
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• Mobile Source Inventory
This section includes the State's approach for determining vehicle miles traveled (VMT) (see
section 5.5.1), specification of the mobile source emissions model used, specification of key
assumptions for the model, including parameters such as temperature, speeds, existing inspection
and maintenance (I/M) programs, etc., and how emissions are temporally and spatially resolved (see
sections 3.2.4 and 3.3).
• Biogenic Source Inventory
This section identifies what source categories are included in the inventory (see section 3.2.2), how
emission are estimated, how data are identified and collected, and how emissions are temporally and
spatially resolved and supplied.
• Documentation Approach
This section describes how the inventory and its procedures are documented and how the data are
stored and managed (see section 6.2). In addition, this section includes information on how the data
are transmitted to EPA (see section 4.7).
• Quality Assurance Plan
This section includes a description of the inventory QA program and QA/QC procedures, as well as
specification of the inventory data quality objectives (DQOs) (see section 6.1).
Each State should negotiate its IPP submittal schedules with its EPA Regional Office. The State and
its Regional Office should agree in advance on the time table for submitting the IPP and the approval
process that will be used by the EPA Regional Office. EPA Headquarters and Regional Offices will
work together to promote consistency of IPP review and approval, while allowing maximum flexibility to
the States in their inventory preparation process.
During the preparation of their IPPs, States are referred to Volume I of the EIEP guidance which
discusses emission inventory planning and development.2 Chapter 2 of Volume IV, Quality
Assurance/Quality Control, of the EIIP guidance provides additional information on planning and
documentation of inventory development and QA activities.3
2.5 INVENTORY APPROVAL
States should negotiate the emission inventory approval process with their respective EPA Regional
Office. Of the emission inventories that States submit to EPA, those that are deemed to be of "regulatory
significance" will require EPA approval. In general, this means that the approval process will include the
emission inventory as a component of a SIP submittal, or other significant action by the State, that
requires EPA review and approval. This represents a change from the policy with the 1990 inventories,
which required States and EPA to subject the 1990 inventory to a public hearing and regulatory approval.
This modification recognizes, and thus eliminates, the additional burden to States to have a separate
inventory approval process. This modification also allows inventory revisions to continue to occur after
initial compilation as application of the inventory in control strategy evaluation and urban or regional
scale modeling reveals where improvements/adjustments are needed.
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SECTION 3.0
EMISSION INVENTORY REQUIREMENTS
The purpose of this section is to identify and explain the key elements to be included in statewide
SEP emission inventories that should be prepared by State and local agencies to comply with the 8-hour
ozone NAAQS, PM25 NAAQS, and regional haze rule. If a State or local agency is unclear on how this
guidance applies to its specific situation, it should consult with its EPA Regional Office for clarification.
This section identifies the uses and required components of the base year and modeling inventories
discussed in this guidance document. This section also discusses the temporal allocation, spatial
allocation, and speciation methodologies used to process the inventories for input to photochemical air
quality models to enable State and local agencies the opportunity for supplying data to improve the
methodologies.
3.1 IDENTIFICATION OF INVENTORY USES
The uses of inventories determine the information that should be included in the inventories. The
emission inventories covered by this guidance document will be used by State and local agencies to
develop their SIPs to demonstrate attainment of the 8-hour ozone NAAQS, PM, 5 NAAQS, and regional
haze rule. As discussed in section 2.2, these inventories include the base year and modeling inventories.
These inventories will also be used by regional planning bodies and EPA to support regional and national
analyses, which in turn will be given to State and local agencies to support development of their SEPs.
The base year inventory is the starting point from which the other SIP inventories are derived. One
of its key purposes is to support air quality modeling and control measure analyses to determine the types
and amounts of emission reductions needed to demonstrate attainment. Emissions trading programs
could also be based on the inventory if emissions trading programs are adopted as a measure of
implementing controls. The results of these studies are then used by State and local agencies to identify
the emission sources for control, and to develop and adopt the control measures that should be included
in the overall control strategy for a SIP. The draft CERR presented in Appendix A specifies the data
elements that State and local agencies should include in their inventories.
Recent studies have indicated that the long-range transport of precursor emissions contribute to
elevated ozone and PM2 5 levels and visibility impacts in down-wind areas. Thus, EPA will support State
and local agencies in conducting regional scale photochemical modeling for all three of these programs
to provide State and local agencies with a number of critical data bases for use in developing their
attainment demonstration and maintenance SEPs. Since EPA has recently published a regional NOX
control strategy for reducing ozone levels for 22 eastern United States and the District of Columbia, this
support in the near term is expected to focus on PM2 5 and regional haze SEP development. To support
this effort, EPA will compile inventories that will include a blend of inventory data submitted by State
and local agencies with inventory data developed by EPA. EPA developed data will be used to fill gaps
in State data and for certain source types where EPA has developed accurate and comprehensive
emission estimates (e.g., electric utility sources). EPA is developing a Data Incorporation Plan which
will document in detail how EPA plans to use State and EPA developed data. These inventories will be
stored in a central repository termed the NET data base. The EPA will also improve the NET data base
for other regional studies as the needs arise. The NET data base will be updated annually with the
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emphasis on incorporating State data using the 3-year cycle inventories submitted by State and local
agencies.
3.2 COMPONENTS OF THE BASE YEAR AND 3-YEAR CYCLE INVENTORIES
3.2.1 Pollutants and Pollutant Precursors to Be Inventoried
This section identifies the pollutants that must be included in the base year and a 3-year cycle
inventory for the 8-hour ozone NAAQS, PM25 NAAQS, and regional haze rule. Because many sources
emit more than one of the precursor pollutants, and because the precursor pollutants have the potential to
be transported across State boundaries, it is important that State and local agencies develop a single
statewide inventory of pollutants to support integrated, regional scale modeling, and control strategy
development for ozone, PM2 5, and regional haze.
For the 8-hour ozone NAAQS, the pollutants to be inventoried are volatile organic compounds
(VOC), NOX, and carbon monoxide (CO).
For the PM25 NAAQS, the pollutants to be inventoried are primary emissions (including
condensibles) of PM10 and PM25, and the precursor emissions SOX, NH3, VOC, and NOX. The EPA is
requiring PMIO emissions to be reported because PM10 is a criteria pollutant and PM10 emissions are
needed as an input to air quality simulation models when modeling PM25.
For regional haze, the pollutants to be inventoried include all of the pollutants and precursor
pollutants identified for ozone and PM, except for CO. While elemental carbon (EC) and organic carbon
(OC) will be identified in default speciation profiles, more locally-specific data should be collected
where available as an input to model preprocessing. Where such data are available, they should be
provided to EPA to help in improving EPA's speciation profiles. State/local agencies can contact EPA's
Emission Factor and Inventory Group (EFIG) for more information.
EPA's current regulatory definition of VOC (40 CFR § 51.100) excludes constituents considered to
be negligibly photochemical!)' reactive. These include methane, ethane, methylene chloride, 1,1,1-
trichloroethane (TCA), several Freon compounds, acetone, perchloroethylene, and others. It is
anticipated that additional compounds may be exempted from this VOC definition. The exempt
compounds are considered negligibly reactive, although some can influence the formation of ozone when
present in sufficient amounts. In preparing the base year inventory, States should consider how the VOC
data are to be used in air quality modeling studies and the techniques available to the State in estimating
VOC emissions. Therefore, should a State or local agency encounter a situation where its emission
estimation methodology includes emissions exempted from EPA's definition of VOC, it should consult
with its modeling staff and EPA Regional Office for guidance and include its plan for addressing the
situation in its IPP. States should specify in their documentation what they are reporting as VOC.
Generally, the emission factors used to estimate organic emissions represent nonmethane
hydrocarbons (NMHCs). Because of this, it is generally assumed that inventories do not have methane,
and part of the modeling procedure "automatically" adds back that missing VOC component. Therefore,
inventory preparers should not have to do anything further specific to methane. State and local agencies
should confirm this with their air quality modeling staff.
At a minimum, it is of utmost importance to document what the inventory contains (e.g., specify
what VOC species are included and any negligibly reactive VOC that are segregated/excluded). If the
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State is reporting VOC as defined by EPA (40 CFR § 51.100), the State should simply state this in both
the IPP and the inventory documentation.
The PM25 and PM10 emission values that should be reported in the inventory should be primary PM.
For the purpose of this guidance document, the following definitions apply:
• PRIMARY PM: Particles that enter the atmosphere as a direct emission from a stack or an
open source. It is comprised of two components: Filterable PM and Condensible PM.
• FILTERABLE PM: Particles that are directly emitted by a source as a solid or liquid at stack
or release conditions and captured on the filter of a stack test train.
• CONDENSIBLE PM: Material that is vapor phase at stack conditions, but which condenses
and/or reacts upon cooling and dilution in the ambient air to form solid or liquid PM
immediately after discharge from the stack.
• SECONDARY PM: Particles that form through chemical reactions in the ambient air well
after dilution and condensation have occurred. Secondary PM is usually formed at some
distance downwind from the source. Secondary PM is NOT reported in the emission
inventory.
In reporting their PM emissions to the EPA, States should report the following:
• Primary PM2 5 (or Filterable PM2 5 and Condensible PM individually. Note that all Condensible
PM is assumed to be in the PM, 5 size fraction)
• Primary PM10 (or Filterable PM10 and Condensible PM individually)
It is preferred that the States report the two separate components rather than the single combined
Primary PM values, if known. This information is important to assist in the development of new
emission factors for Condensible PM. If only the filterable component is known, report it as "filterable."
In addition, States may also choose to report the following:
• Total Primary PM Measured (or Filterable Total Primary PM Measured and Condensible PM
individually)
These two PM components are the components measured by a stack sampling train such as EPA
Method 5 and have no upper particle size limit.
States should be careful to identify the PM components that they are reporting using the above
terms. If a State does not identify what PM components are being reported, the EPA will assume that the
emissions represent only the Filterable PM component.
3.2.2 Identification of Sources and Source Categories to Be Inventoried
The base year inventory should include all stationary point and area, nonroad mobile, onroad
mobile, biogenic, and geogenic emission sources present within each county within a State. Even if there
are areas within a State that do not have significant emissions, the State should still prepare a statewide
inventory (the State may, however, elect to use the NET inventory data for those areas). EPA's EFIG
maintains the Clearing House for Inventories and Emission Factors (CHIEF) web site
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(http://www.epa.gov/ttn/chief/) to provide access to the latest information and tools for identifying
emission sources and estimating emissions of air pollutants and preparing air emission inventories. The
CHIEF web site provides access to the list of point, area, and mobile source classification codes (SCCs).
Note that EPA plans to revise the current SCC reporting system. The new reporting codes, likely to
be termed process category codes (PCCs), will be accommodated by the NET input format. Once the
new reporting system is established, EPA will accept an emission inventory based on either SCCs or
PCCs (i.e., EPA will not set a deadline by which time States are required to use the new system). EPA
expects to develop a crosswalk for converting codes from the existing reporting system to the new
system. In addition, for point source reporting under the CERR, a State is required to specify the
Standard Industrial Classification (SIC) code. The U.S. Department of Commerce, Bureau of the Census
has developed the North American Industry Classification System (NAICS) to replace the SIC system.
The NAICS was developed jointly by the United States, Canada, and Mexico to provide new
comparability in statistics about business activity across North America. Correspondence tables to map
NAICS codes to SIC codes (or SIC codes to NAICS codes) have also been developed by the Bureau of
the Census.
Section 5.0 of this document provides tables which list in detail the source categories that EPA
believes are significant sources for the pollutants in the tables. This section also lists the source
categories for which EIIP procedures guidance has been developed. As new EIIP guidance is issued for
source categories discussed in section 5.0, the EIIP guidance should be used in lieu of the section 5.0
information, and can be accessed through the EIIP web site at http://www.epa.gov/oar/oaqps/eiip/.
3.2.3 Geographic Coverage
The base year inventory must be prepared for all sources for the entire State regardless of the
attainment status of counties within the State. Even if there are areas within a State that do not have
significant emissions, the State must still prepare a statewide inventory. The State may elect to use the
EPA supplied NET inventory for those areas. Emissions for area, nonroad mobile, onroad mobile,
biogenic, and geogenic emissions should be provided at the county level. The geographic location of
emissions for point sources should be defined by their coordinates [i.e., latitude and longitude (decimal
degrees) or universal transverse mercator (UTM)].
Because of the regional nature of the pollutants, statewide inventories are necessary to support air
quality modeling to identify the scale of the pollutant problem (i.e., local versus regional), which in turn
will support evaluation and development of cost-effective control strategies. The draft CERR in
Appendix A specifies the criteria for defining point sources in attainment and nonattainment areas and
the frequency for reporting point source data. The draft CERR also specifies the criteria for defining
area, nonroad mobile, onroad mobile, and biogenic sources, and the reporting frequencies for these
sources. The draft CERR includes reporting requirements for all NAAQS criteria pollutants and
precursors, the Section 110 NOX SIP Call, and HAPs. Although this guidance document is only
concerned with the 8-hour ozone and PM25 NAAQS, and the regional haze rule, State and local agencies
are encouraged to coordinate their emission inventory development efforts for these other programs to
minimize duplication of effort while compiling their inventories for the 8-hour ozone and PM2 5 NAAQS,
and the regional haze rule.
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3.2.4 Temporal Basis of Emissions
This section addresses the temporal resolution of the emissions data that should be provided in the
base year and 3-year cycle inventories. Discussion of how emissions are temporally allocated for air
quality modeling purposes is provided in section 3.3.1. Temporal adjustments to annual emissions
included in the inventory are made because of seasonal differences in the rate of emissions or activity, or
to apportion emissions to a particular season or day. State and local agencies should consult EIIP
guidance for temporal adjustment procedures. It is important that State and local agencies develop a
single integrated annual statewide inventory.
For the 8-hour ozone NAAQS emission inventory, VOC, NOX, and CO emissions should be reported
as actual annual and actual summer weekday. Summer weekday emissions are defined as an average
day's emissions for a typical summer day during the ozone season. These temperature data are provided
to the air quality model by meteorological inputs developed for the specific days which are modeled.
This information, in turn, is used by emissions models to "adjust" initial information provided by the
State. It is only necessary to choose a summer weekday and make note of the diurnal temperature pattern
used on a selected day. The emissions model will make adjustments for temperatures observed on the
actual days which are modeled. For modeling purposes, EPA also urges providing estimates for a
weekend day, which may reflect different activity levels and patterns. Note that in certain situations,
weekend emissions may dominate some episodes, and, therefore, the inventory will be needed to support
those analyses.
For the PM25 NAAQS and regional haze rule emission inventories, direct emissions (including
condensibles) of PM10 and PM25. and the precursor emissions VOC, NOX, SOX, and NH3 should be
reported as actual annual. Temporal allocation of the inventories to other time scales (e.g., daily) will be
made during preprocessing of the inventories for modeling, based on temporal allocation profiles.
Alternatively, the State or local agency may choose to include actual temporally resolved emissions data
in its inventory (see section 3.3).
The State or local agency should discuss in its IPP its approach for preparing and supplying
temporally resolved emissions.
3.2.5 Rule Effectiveness and Rule Penetration
For ozone inventories, RE is still required as it has been in the past (i.e., each State or local agency
should negotiate the application of RE and RP with its EPA Regional Office and include the decisions in
its IPP). The inventory documentation should note when RE or RP are applied and what the factors are.
RE reflects the ability of a regulatory program to achieve all the emission reductions that could have
been achieved by full compliance with the applicable regulations at all sources at all times. The concept
of applying RE in a SIP emission inventory has evolved from the observation that regulatory programs
may be less than 100 percent effective for some source categories. Should a State include RE, it should
be applied to all sources that are affected by a regulation and for which emissions are determined by
means of emission factors and control efficiency estimates. Thus, the RE factor is only applied to
controlled emission sources (point) or source categories (area). No RE is needed in cases where no
control is applied or there is no applicable regulation. Several factors should be taken into account when
estimating the effectiveness of a regulatory program. These include: (1) the nature of the regulation
(e.g., whether any ambiguities or deficiencies exist, whether test methods and/or recordkeeping
requirements are prescribed); (2) the nature of the compliance procedures (e.g., taking into account the
long-term performance capabilities of the control); (3) the performance of the source in maintaining
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compliance over time (e.g., training programs, maintenance schedule, recordkeeping practices); and
(4) the performance of the implementing agency in assuring compliance (e.g., training programs,
inspection schedules, follow-up procedures). For further information on RE, the reader is referred to
EPA guidelines for estimating and applying RE for ozone and CO SIP base year inventories.4
Rule penetration is an estimate of the extent to which a regulation covers emissions from an area
source category for a specified control area (e.g., county, group of counties making up a nonattainment
area, or statewide). Thus, RP is applied to the control efficiency for a regulation to account for less than
100 percent coverage of the emissions for an area source category. For example, if a control measure is
applied to an area source fuel combustion category to control emissions from the largest emission sources
within the category, then RP could be applied to the control efficiency for the control measure to account
for the percentage of emissions for the source category that are affected by the control measure. For area
sources, RP and RE should be applied at the SCC level.
For information on applying RE, State/local agencies can consult the EIIP draft document Emission
Inventories and the Proper Use of Rule Effectiveness, available at the following web site:
http://www.epa.gov/ttnchiel/eiip/pointsrc.htm.
For PM2 5 and regional haze inventories, large contributions to overall emissions are of an
uncontrolled area source nature, and there is insufficient evidence to draw broad conclusions on the
application of RE/RP. Therefore, RE/RP will not be applied to PM2 5 and regional haze inventories.
EPA is currently reviewing its policy on RE and RP. If changes to the existing policy are made,
EPA will announce these changes through a policy memorandum.
3.3 MODELING INVENTORIES
This section explains the procedures by which emissions in a completed base year or projection year
inventory are temporally allocated, spatially allocated, and speciated for use in a photochemical grid
model. By explaining these procedures, it is anticipated that State and local agencies will be able to
provide more complete and accurate data to increase the accuracy of the procedures. Note, however, that
the information on preparing gridded inventories is presented for informational purposes and is not
required for States. The procedures discussed are those applied in the emission inventory preprocessor
currently being used by EPA, which, for this purpose, is based on the Emissions Modeling System,
version 1995 (EMS-95). The procedures more than likely will be revised to incorporate improvements to
the emission inventory/modeling interface, therefore, State and local agencies should consult with their
modeling staff and EPA Regional Office to verify the procedures that will be used to process their
inventory data for modeling, and make adjustments as needed. Once these decisions have been made,
State and local agencies should document their approach in the IPP. As such, the following discussion of
EMS-95 is presented as an example of a method to process data for photochemical grid modeling, and
States are not required to use EMS-95.
It is possible that States will need to develop microscale, day-specific inventories to support air
quality modeling efforts. These detailed emission inventories may be developed for any number of
state-specific purposes, including model performance evaluation. However, if States develop a more
detailed modeling inventory, the emissions do not need to be reported to EPA.
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3.3.1 Temporal Allocation Procedures
Because of the different data elements reported for point, area, and mobile sources, the preprocessor
contains separate procedures for temporally allocating their emissions. The following sections describe
the procedures used for point, area and mobile sources, respectively.
3.3.1.1 Point Sources
EMS-95 temporally allocates emissions estimates based on source-specific operating schedule data
that are input to the preprocessor. EMS-95 recognizes the following forms of operating schedule data:
• monthly throughput fractions (January through December)
• seasonal throughput fractions (where winter = December, January, and February;
spring = March, April, and May; summer = June, July, and August; and fall = September,
October, and November)
• hours per year in operation
• days per year in operation
• weeks per year in operation
• days per week in operation
• hours per day in operation
Any, none, or all of the operating schedule data can be supplied. If no operating schedule data are
supplied, EMS-95 uses a default operating schedule based on SCC-specific profiles for point sources.
However, custom profiles were not available and were not incorporated into EMS-95 for all SCCs.
Therefore, in many cases the SCC-specific profiles simply reflect 24 hours per day, 7 days per week, and
12 months per year of operation.
If some or all of the operating data are provided, EMS-95 uses a hierarchy of the operating schedule
data to determine how to compute the temporal factors. In this hierarchy, the monthly temporal factor is
computed first, followed by the weekly temporal factor, then the daily temporal factor, and finally, the
24 hourly temporal factors.
To determine the monthly temporal factor, EMS-95 employs the following steps:
• Step 1. If valid monthly throughput values are available, the monthly temporal factor is set to
the monthly throughput value of the month being modeled.
• Step 2. If a value is not obtained in Step 1 and valid seasonal throughput values are available,
the monthly temporal factor is set to one-third of the seasonal throughput value of the season
being modeled.
• Step 3. If monthly and seasonal throughput values are not available, the monthly temporal
factor is set to 0.083 or 1/12 for equal monthly throughput values.
To determine the weekly temporal factor, EMS-95 determines the number of days in the month
being modeled and divides that value by 7 days per week.
To determine the daily temporal factor, EMS-95 examines the values for days per week in operation.
If it is a valid value (i.e., from 0 to 7), no additional action is needed to determine days per week for that
source. If it does not have a valid value, EMS-95 assigns a value by examining the hours per year in
17
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operation, days per year in operation, and weeks per year in operation fields, and using the following
assumptions:
• hours per year in operation (houryear)
if 0 < houryear < 850, then days per week = 2
if 850 < houryear < 1250, then days per week = 3
- if 1250 < houryear < 1670, then days per week = 4
if 1670 < houryear < 2100, then days per week = 5
- if 2100 < houryear < 2500, then days per week = 6
- if 2500 < houryear, then days per week = 7
• days per year in operation (dayyear)
- if 0 < dayyear < 110, then days per week = 2
- if 110 < dayyear < 160, then days per week = 3
if 160 < dayyear <210, then days per week = 4
- if 210 < dayyear < 260, then days per week - 5
if 260 < dayyear < 315, then days per week = 6
- if 315 < dayyear, then days per week = 7
• weeks per year in operation (weeks)
- if 0 < weeks <7, then days per week = 1
- if 7 < weeks < 13, then days per week = 2
- if 13 < weeks, •- 19, then days per week = 3
if 19 < weeks <26, then days per week = 4
- if 26 < weeks < 33, then days per week = 5
if 33 < weeks < 39, then days per week = 6
- if 39 < weeks, then days per week = 7
To determine the hourly temporal factor, EMS-95 checks the hours per day in operation field for the
source, and if there is a valid value, EMS-95 takes no other actions to determine the hours per day in
operation value for the sources. If there is not a valid value, EMS-95 assigns a value by examining the
hours per year in operation, days per year in operation, and weeks per year in operation fields. If any of
these fields have a valid value, hours per day in operation is assumed to be 8. If hours per day in
operation or days per week in operation cannot be assigned through the methods described here, hours
are assumed to be 24 and days are assumed to be 7.
EMS-95 uses the temporal factors to allocate emissions to hourly values. The temporal factors are
applied based on how the emissions estimates were reported to the preprocessor (as annual average, day-
specific, or average day emissions).
• If the emissions data are annual average emissions, reported emissions are multiplied by
(1) the product of monthly temporal factor divided by the weekly temporal factor, then by
(2) the day of week temporal factor, and then by (3) the hourly temporal factor, to get the
hourly emissions estimate.
• If the emissions data are average day emissions and the monthly factor, weekly factor, or day
of week factor is zero, then emissions are assumed to be zero for each hour.
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• If the emissions data are average day emissions and none of the factors (the monthly temporal
factor, weekly temporal factor, or day of week factor) is zero, then emissions are multiplied by
the hourly factor.
• If the emissions data are reported as day-specific emissions, then the emissions are multiplied
by day-specific hourly temporal factors.
The States are encouraged to provide the modelers with as much operating data as possible for each
point source. Use of actual data results in more accurate temporal allocation, and less data manipulation
and fewer assumptions from the preprocessor.
3.3.1.2 Area and Mobile Sources
EMS-95 uses the Temporal Allocation Factor File (TAFF) developed for the 1985 National Acid
Precipitation Assessment Program (NAPAP) to temporally allocate area source emissions. The temporal
allocation factors take the form of three sets of fractional multipliers, as follows:
(1) Four seasonal factors divide the annual total into four subtotals representing emissions for each
season.
(2) Three daily factors per season divide each seasonal total into three subtotals representing
emissions for a typical weekday. Saturday, and Sunday in each season.
(3) Twenty-four hourly factors per day divide each daily total into 24 subtotals representing
emissions for each hour of the day.
The seasonal multipliers for each record sum to one, as do the hourly multipliers for each season/day
combination. Since daily emissions totals represent emissions for one typical weekday, Saturday, or
Sunday in each season, the overall equation for daily allocation factors is:
(65 x weekday factor) + (13 x Saturday factor) + (13 x Sunday factor) = 1
where a season is defined as 91 days (13 weeks).
Temporal allocation factors were developed for the area source categories in the 1985 NAPAP area
source file. Depending on the magnitude of emissions within the category and the availability of data,
some factors were resolved to the regional, State, or county level (i.e., different sets of factors for each
region, State, and county for a given source category). Table 2-1 of The 1985 NAPAP Emissions
Inventory: Development of Temporal Allocation Factors5 (herein referred to as the TAP document) lists
the NAPAP area source categories, including the level of resolution for each temporal pattern.
Appendix D of the TAF document contains the listing of all 212 unique temporal profiles used to allocate
area source emissions, including a key to the temporal profile usage. Section 2 of the TAF document
describes how the temporal allocation factors were developed for each area source category.
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The following example profile listing was excerpted from Appendix I) of the TAP document.
DAY HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR HR
PROFILE NBR SEA DAY 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
A001
1
2
3
4
5
6
7
8
9
10
11
621
621
621
201
201
201
000
000
000
178
178
0110
0110
0110
0110
0110
0110
0000
0000
0000
0110
0110
051
051
051
083
083
083
000
000
000
067
067
051
051
051
083
083
083
000
000
000
067
067
051
051
051
083
083
083
000
000
000
067
067
057
057
057
110
110
110
000
000
000
106
106
057
057
057
110
110
110
000
000
000
106
106
057
057
057
110
110
110
000
000
000
106
106
048
048
048
127
127
127
000
000
000
120
120
048
048
048
127
127
127
000
000
000
120
120
048
048
048
127
127
127
000
000
000
120
120
047
047
047
013
013
013
000
000
000
000
000
047
047
047
013
013
013
000
000
000
000
000
047
047
047
013
013
013
000
000
000
000
000
028
028
028
000
000
000
000
000
000
000
000
028
028
028
000
000
000
000
000
000
000
000
028
028
028
000
000
000
000
000
000
000
000
016
016
016
000
000
000
000
000
000
000
000
017
017
017
000
000
000
000
000
000
000
000
016
016
016
000
000
000
000
000
000
000
000
038
038
038
000
000
000
000
000
000
000
000
037
037
037
000
000
000
000
000
000
000
000
038
038
038
000
000
000
000
000
000
000
000
047
047
047
000
000
000
000
000
000
040
040
048
048
048
000
000
000
000
000
000
040
040
047
047
047
000
000
000
000
000
000
040
040
12 178 0110 067 067 067 106 106 106 120 120 120 000 000 000 000 000 000 000 000 000 000 000 000 040 040 040
Using the key in Appendix D, profile A001 corresponds to NAPAP area source categories 001 through
006 (residential fuel - anthracite coal, bituminous coal, distillate oil, residual oil, natural gas, and wood,
respectively) for the State of Alabama. Under the DAY NBR column:
1 = winter weekday
2 = winter Saturday
3 = winter Sunday
4 = spring weekday
5 = spring Saturday
6 = spring Sunday
7 = summer weekday
8 = summer Saturday
9 = summer Sunday
10 = fall weekday
11 = fall Saturday
12 = fall Sunday
The numbers in the SEA column represent the seasonal factors used to divide the annual emissions into
seasonal totals. For profile A001. the winter seasonal factor is 621, which means that 62.1 percent of the
total annual activity occurs in the winter.
The numbers in the DAY column represent the daily factors used to divide the seasonal emissions
into typical weekday, Saturday, and Sunday emissions. For profile A001, the winter weekday factor is
0110, which means that 1.10 percent of the seasonal activity occurs during each weekday.
The numbers in each HR column represent the hourly factors. For profile A001 on a winter
weekday, the fraction for HR 1 is 051, which means that 5.1 percent of the total daily activity for this
source category occurs during hour 1 of the day.
States and local agencies can review the area source temporal allocation factors used by EMS-95,
and, if they feel that the these factors are not representative of actual activity for a specific area source
category in their area, they may submit alternative profiles to be used with their area source emissions
inventory. If an agency elects to submit alternative temporal allocation factors, it should clearly indicate
which categories the alternative factors should be applied to, as required in the CERR.
The Motor Vehicle Emissions Estimates Model (MoVEM) is used to compute emissions estimates
from onroad mobile sources in EMS-95. MoVEM is a true model because it computes gridded, hourly
20
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emissions estimates from fundamental traffic and emissions data (e.g., VMT, vehicle mix, emission
factors). VMT estimates are temporally allocated by MoVEM in the following manner. Prior to
computing the motor vehicle emissions estimates, MoVEM adds gridded, hourly temperatures and
adjusts the VMT to the specific modeling day. The temperature data are used to obtain the correct
emissions factor from the MOBILE emissions factors lookup tables. Through the application of the
following equations, MoVEM computes the day-specific, diurnal and nondiurnal, hourly VMT.
dvmt,Jilihimin = ddayvmtliliiim,n * adjday * adjmonth * dvmt_prof,jjih
ovmt.j|_hmn = odayvmt,, Jm n * adjday * adjmonth * ovmt_profljriih
dvmtl)af,mn = ddayvmtljatin * adjday * adjmonth * dvmt_prof,J>aifih
ovmtljafmn = odayvmt,jafn * adjday * adjmonth * ovmt_profyia.,,h
where: dvmt is the diurnal VMT;
ddayvmt is the total day diurnal VMT;
adjday is the day-specific VMT adjustment factor supplied through the ASCII input file
adjsftmt.mv;
adjmonth is the month-specific VMT adjustment factor supplied through the ASCII input file
adjsft'mt.mv;
dvmt_profis, the hour-specific, diurnal VMT fractional profile factor;
ovmt is the nondiurnal VMT;
odayvmt is the total day nondiurnal VMT;
ovmt_prof\s the hour-specific, nondiurnal VMT fractional profile factor;
/ is the State index;
j is the county index;
/? is the hour index;
/ is the link identifier index;
a is the area type index;
/is the facility type index;
m is the east-west grid cell index; and
n is the north-south grid cell index.
If the user supplies limited data to MoVEM, MoVEM can apply a variety of default values to
compute motor vehicle emissions estimates. For temporally allocating VMT, MoVEM applies the
following default fractional profile for estimating hourly VMT from day-specific and month-specific
VMT supplied by the user (Table 3.3-1).
21
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Table 3.3-1. Default Hourly VMT Fractional Profile
Emission
Diurnal
Other
Hour
1
0.000
0.016
2
0.000
0.010
3
0.000
0.003
4
0.000
0.006
5
0.000
0.010
6
0.129
0.026
7
0.021
0.053
8
0.100
0.064
9
0.095
0.055
10
0.095
0.048
11
0.166
0.050
12
0.199
0.052
Diurnal
Other
13
0.079
0.054
14
0.116
0.055
15
0.000
0.059
16
0.000
0.070
17
0.000
0.074
18
0.000
0.070
19
0.000
0.058
20
0.000
0.046
21
0.000
0.037
22
0.000
0.033
23
0.000
0.028
24
0.000
0.022
3.3.2 Spatial Allocation Procedures
To prepare emissions for photochemical modeling, these emissions should be spatially allocated
both horizontally and vertically. Horizontal spatial allocation refers to placing the emissions in the
proper grid cell on the emissions modeling grid to be used in the modeling exercise. Vertical spatial
allocation refers to placing the emissions in the proper layer, that is, distance into the atmosphere, in
which emissions are deposited. Spatial allocation procedures used for point sources are different than
those used for area and mobile sources. Procedures used for spatial allocation of point source and
area/mobile source emissions are described below.
3.3.2.1 Point Sources
Horizontal Spatial Allocation
Point sources are spatially allocated to an emissions modeling grid by the UTM coordinates of a
stack or by the UTM coordinates of the facility. These geographic coordinates should be supplied as part
of the point source inventory. If they are supplied as latitude/longitude coordinates rather than UTM
coordinates, they must be converted to UTM prior to input to EMS-95.
The EMS-95 Point Source Location Processor prepares an ASCII file of point source identifiers and
point source UTM locations. The Point Source Grid Processing Module reads the ASCII file that was
generated by the Point Source Location Processor, generates the appropriate ARC/INFO® coverages, and
prepares two ASCII files:
• a file which contains point source identifiers and grid cell location
• a file which contains point source identifiers and latitude/longitude coordinates
Point sources that have neither stack coordinates nor facility coordinates are placed in the center of the
county, and EMS-95 reports on the point sources so placed. The process of assigning grid coordinates to
point sources is an ARC/INFO® function; therefore, the technical formulation is embedded within the
ARC/INFO® software. Please refer to the ARC/INFO® documentation for a discussion on coverage
manipulation.6
22
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Vertical Spatial Allocation
The vertical layer that point source emissions are deposited in is based on the plume rise of the
emissions. The plume rise of emissions is calculated based on the stack parameters supplied in the point
source inventory. Therefore, it is important that State/local agencies provide accurate st
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After the user has populated the appropriate files, EMS-95 grids the necessary data sets per the
requirements of the user-defined spatial surrogates. Spatial surrogates, and their data source, that have
been used in prior modeling exercises are shown in Table 3.3-3.7 In some cases a surrogate (e.g.,
agriculture) will not exist in a county though an emissions estimates for an area source category
(e.g., farm harvesting equipment) may be assigned to the surrogate. In such a case, the area source
category is assigned a secondary surrogate (e.g., rural). If the secondary surrogate also does not exist in
the county, the population surrogate acts as the default since population covers the entire domain. Note
that it is possible to recombine the data in Table 3.3-3 to develop other area source spatial surrogates, if
so desired. EPA encourages the use of the best available, most representative, data for use as the spatial
surrogates.
The surrogate is computed as the sum of the values that comprise the surrogate in a grid cell divided
by the sum of the values that comprise the surrogate in a county, as shown in the following equation:
£
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Table 3.3-3. Area Source Spatial Surrogates7
Surrogate
Agriculture
Airports
Area
Housing
Inverse housing
Inverse
population
Major highways
Population
Ports
Railroads
Water
Rural
Urban
Description
Derived from the LCC25 data base.9 Comprised of the categories: dryland,
cropland, and pasture; irrigated cropland and pasture; mixed dryland/irrigated
cropland and pasture; grassland/cropland mosaic; and woodland/cropland
mosaic. Resolution of data is 1.1 kilometers. Surrogate exists for both U.S. and
Canada.
Derived from the post-1990 TIGER/Line data base.10 Comprised of major
national and international commercial airports and large private airstrips. Point
value; no resolution. Surrogate exists only for U.S.
Derived from grid coverage developed by EMS-95 Grid Definition Model.
Resolution of data is 1 ,000 meters. Surrogate exists for both U.S. and Canada.
Derived from the post-1 990 census data base.11 Comprised of all single and
multiple family housing units. Resolution of data is census tract (about 2,000
meters). Surrogate exists only for U.S.
Derived from the post-1 990 census data base.11 Resolution of data is census
tract (about 2,000 meters). Surrogate exists only for U.S.
U.S. data derived from the post-1990 census data base.11 Resolution of data is
census tract (about 2000 meters). Canadian data are derived from gridded world
population data12 with resolution of about 5'. Surrogate exists for both U.S. and
Canada.
Derived from the Federal Highway Authority v.2.0 national planning network.8
Resolution of data is 3000 meters. Surrogate exists only for U.S.
Derived from the post-1990 census data base.12 Resolution of data is census
tract (about 200 meters). Canadian data are derived from gridded world
population data12 with resolution of about 5'. Surrogate exists for both U.S. and
Canada.
Derived from the post-1 990 TIGER/Line data base.10 Comprised of major
national and international commercial shipping ports. Point value; no resolution.
Surrogate exists only for U.S.
Derived from the National Railway Network.13 Resolution of data is 3,000 meters.
Surrogate exists only for U.S.
Derived from LCC25 data base9 and post-1 990 census data base.11 Comprised
of the water category plus ocean. Resolution of LCC25 data base is 1 .1 kilometer
and resolution of census data base is census tract (about 2,000 meters).
Surrogate exists for both U.S. and Canada.
All areas not Urban. Resolution of data is census tract (about 2,000 meters).
Surrogate exists for both U.S. and Canada.
Derived from the post-1990 census data base.11 Determined to be all areas with
populations of 25,000 or more. Resolution of data is census tract (about 2,000
meters). Canadian data are derived from the LCC25 Canada data base.9
Surrogate exists for both U.S. and Canada.
25
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Table 3.3-4. Four-digit Area Source Category Codes and the Predominant
Area Source Spatial Surrogate
4-digit
Area
Source
Category
2101
2102
2103
2104
2199
2260
2265
2270
2275
2280
2282
2283
2285
2294
2296
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2325
2390
2399
2401
2415
2420
2425
2430
2440
2460
2461
2465
2500
2501
2505
2510
2601
2610
2620
2630
2640
2660
2801
2805
2810
2830
2850
Major Category Description
(2-digit Area Source Category)
Stationary Source Fuel Combustion
Stationary Source Fuel Combustion
Stationary Source Fuel Combustion
Stationary Source Fuel Combustion
Stationary Source Fuel Combustion
vlobile Sources
Mobile Sources
Mobile Sources
Mobile Sources
Mobile Sources
Mobile Sources
Mobile Sources
Mobile Sources
Mobile Sources
Mobile Sources
ndustnal Processes
ndustrial Processes
ndustnal Processes
ndustrial Processes
ndustrial Processes
ndustrial Processes
ndustrial Processes
ndustnal Processes
ndustrial Processes
ndustna! Processes
ndustnal Processes
ndustnal Processes
ndustnal Processes
ndustnal Processes
ndustrial Processes
Solvent Utilization
Solvent Utilization
Solvent Utilization
Solvent Utilization
Solvent Utilization
Solvent Utilization
Solvent Utilization
Solvent Utilization
Solvent Utilization
Storage and Transport
Storage and Transport
Storage and Transport
Storage and Transport
Waste Disposal, Treatment, and Recovery
Waste Disposal, Treatment, and Recovery
Waste Disposal, Treatment, and Recovery
Waste Disposal, Treatment, and Recovery
Waste Disposal, Treatment, and Recovery
Waste Disposal, Treatment, and Recovery
Miscellaneous Area Sources
Miscellaneous Area Sources
Miscellaneous Area Sources
Miscellaneous Area Sources
Miscellaneous Area Sources
Minor Category Description
(4-digit Area Source Category)
Electric Utility
ndustnal
Commercial/Institutional
Residential
Total Area Source Fuel Combustion
Off-highway Vehicle Gasoline 2-Stroke
Off-highway Vehicle Gasoline 4-Stroke
Off-highway Vehicle Diesel
Aircraft
Marine Vessels Commercial
Marine Vessels Recreational
Military
Railroads
Paved Roads
Unpaved Roads
Chemical Manufacturing SIC 28
Food and Kindred Products SIC 20
Primary Metal Production SIC 33
Secondary Metal Production SIC 33
Mineral Processes SIC 32
Petroleum Refining SIC 29
Wood Products SIC 24
Rubber/Plastics SIC 30
Fabricated Metals SIC 34
Oil and Gas Production SIC 13
Construction. SIC 15- 17
Machinery SIC 35
Mining and Quarrying SIC 14
n-process Fuel Use
ndustnal Processes NEC
Surface Coating
Degreasmg
Dry Cleaning
Graphic Arts
Rubber/Plastics
Miscellaneous Industrial
Miscellaneous Nonindustrial All Classes
Vliscellaneous Nonindustrial Commercial
Miscellaneous Nonindustrial Consumer
•"UNKNOWN*"
Petroleum and Petroleum Product Storage
Petroleum and Petroleum Product Transport
Organic Chemical Storage
On-site Incineration
Open Burning
Landfills
Wastewater Treatment
TSDFs
Leaking Underground Storage Tanks,
Agriculture Production - Crops
Agriculture Production - Livestock
Other Combustion
Catastrophic/Accidental Releases
Health Services
Predominant
Area Source
Spatial
Surrogate
Dopulation
=opulation
Population
Housing
Copulation
Population
Copulation
Population
Airports
Ports
Water
Population
Railroads
Population
Population
Copulation
Population
Copulation
Population
Population
Copulation
Population
Copulation
Population
nverse population
Population
Population
Population
Population
Copulation
Population
Population
Population
Population
Population
Population
Population
Copulation
Population
nverse housing
nverse housing
Population
nverse housing
Inverse housing
Inverse housing
Inverse housing
Population
Population
Population
Agriculture
Agriculture
Inverse population
Inverse population
Population
26
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modeling grid over the off-network coverage, and in the same manner that the area source spatial
surrogates are computed, an off-network VMT surrogate is computed for each area type/facility type
combination. That is, each area type/facility type segment is apportioned to a grid cell in the emissions
modeling domain. Once the networks have been gridded, the corresponding countywide VMT, which is
identified by area type and facility type, is gridded. Though it is extensive, consisting of over 400,000
miles of roadways, the FHWA network does not adequately define all area type/facility type
combinations for which countywide VMT are defined. In such cases, the VMT is apportioned via the
area source population surrogate.
States may use an emissions preprocessor that spatially allocates mobile source emission estimates
instead of VMT, as is done for MoVEM. In these cases, the following horizontal spatial allocation
surrogates are provided as suggestions for spatially allocating non-exhaust emissions from
non-commercial vehicles: for diurnal and evening hot soak emissions, single family housing locations
may be an appropriate surrogate; employment data may be a suitable surrogate for allocating morning hot
soak evaporative emissions.
Vertical Spatial Allocation
Both area and mobile source emissions are assumed to be ground-level sources, that is, deposited
into the surface layer. Therefore, no vertical spatial allocation is needed for these sources.
3.3.3 Speciation Procedures
Prior to describing the methods employed by EMS-95 to speciate emissions supplied by the
emissions submodels, it is necessary to describe the difference between discrete and lumped-model
speciation:14
• discrete speciation - refers to splitting emissions for a pollutant into individual chemical
compounds. For example, total organic gases (TOG) emissions from automobile exhaust may
consist of 50 or more identified organic compounds (e.g., benzene, hexane, formaldehyde,
etc.). Discrete speciation is performed using speciation profiles containing weight fractions for
each chemical compound (e.g., profiles found in EPA's SPECIATE data base);
• lumped-model speciation - refers to splitting emissions for a pollutant into groups of
components that represent numerous discrete compounds. The groups of components are
referred to as lumped-model species. The lumped-model species for TOG are developed using
split factors that are specific to the type of chemical mechanism employed by the
photochemical model to be used.
For example, the UAM model uses the Carbon Bond IV (CB-TV) mechanism, therefore
discrete compounds are lumped together based on the compounds' carbon bond structure. The
single carbon-carbon bond hydrocarbon compounds, for instance, are lumped into the paraffin
(PAR) lumped-model species. For the California Statewide Air Pollution Research Center
(SAPRC) mechanism employed by the Regional Acid Deposition Model (RADM) and the San
Joaquin Valley Air Quality Study/Atmospheric Utilities Signatures, Predictions and
Experiments Regional Modeling Adaption Project (SARMAP) Air Quality Model (SAQM),
discrete compounds are lumped together based on their relative reactivity with the hydroxyl
radical.
27
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The EMS-95 Speciation Model performs lumped-model speciation of TOG emissions. For NOX
emissions, these are discretely speciated into nitric oxide (NO) and nitrogen dioxide (NO2) (and
sometimes HONO). SOX is discretely speciated into SO2 and SO4. The chemical mechanisms supported
by EMS-95 for lumped-model speciation of TOG are the CB-IV and SAPRC mechanisms. However,
EMS-95 does have a module that allows for the use of any other chemical mechanism for developing
split factors (referred to as the External CB-IV Split Factors Module).
The following equation is used to compute CB-IV split factors for TOG emissions:
where: sf = CB-IV split factor (moles of lumped-model species/gram TOG
i = the TOG species profile index
j = the CB-FV lumped-model species index
k = the index for the discrete TOG species in the emissions stream
xmf = mass fraction of discrete TOG species in the emissions stream (grams discrete
TOG species/gram TOG)
mw = molecular weight of the discrete TOG species in the emissions stream (grams
of discrete TOG species/mole of discrete TOG species)
xnum = assignment of lumped-model species to discrete TOG species (moles of
lumped-model species/mole of discrete TOG species)
For the most recent version of EMS-95 (e.g., the version used during the OTAG modeling), the
lumped-model split factors were derived from discrete speciation profiles from EPA's SPECIATE data
base. For other versions of EMS-95, other sources of speciation data may have been used to derive split
factors. Therefore, users should check with their source of the EMS-95 software to determine the origin
of speciation data. As mentioned above, revised split factors can be derived using the External CB-IV
Split Factors Module, if better discrete speciation profiles or lumped-model species assignments (i.e.,
xnum in the equation above) exist. For SEP modeling efforts, any such revisions should be coordinated
with the EPA Regional Office.
The EMS-95 Speciation Model also performs a reactive organic gas (ROG) to TOG adjustment to
account for some emissions measurement techniques that do not capture all of the discrete hydrocarbon
compounds in the emissions stream. This adjustment must be performed since the speciation profiles are
based on TOG, not ROG.
The NO and NO2 split factors for NOX are based on an assumed composition of 90 percent by mass
NO as NO2 and 10 percent NO2. However, the NO mass can vary between 89 and 95 percent by
weight.12 For a small number of cases, HONO mass is also included in the speciation (less than 2 percent
of NOX mass).
In summary, EMS-95 speciates the gridded, hourly emission estimates with the use of the following
equation:12
chemest = ee x rogtotog x (sf/divisor)
28
-------
where: chemest - gridded, hourly lumped-model species emissions estimate (moles/hour)
ee = gridded, hourly emissions estimate (grams/hour)
rogtotog = ROG-to-TOG conversion factor (unitless)
sf - lumped-model species split factor (unitless)
divisor = a conversion factor for lumped-model species other than the TOG species
described above
The development of split factors, sf, for TOG species other than biogenic species are described
above. For biogenic species, the split factors are as follows:
• 1.0 for biogenic isoprene (ISOP)
• 0.5 for olefins from biogenic terpenes [OLEjERP (e.g., one-half mole of olefins from each mole
of biogenic terpenes)]
• 6.0 for paraffins from biogenic terpenes (PARTERP)
• 1.5 for higher molecular weight aldehydes from biogenic terpenes (ALD2TERP)
• 0.5 for olefins from other biogenic VOC (OLEOVOC)
• 8.5 for paraffins from other biogenic VOC (PAROVOC)
• 0.5 for nonreactive organic compounds from other biogenic VOC (NROVOC)
• 0.97 for SO2 (97 percent of SOX is SO2; the remaining 3 percent SO4 is dropped)
1.0 for aerosols (AERO)
1.0 for CO
0.9 for NO (as NO,) and 0.1 for NO2. as described above for NOX
The divisor in the above equation is used to convert emissions from a mass to a molar basis. For
biogenic emissions, the divisor consists of a conversion from micrograms to kilograms and the assumed
molecular weight of the biogenic species: 68.12 for ISOP; 136.23 for TERP; and 86.00 for OVOC. The
divisors used in the equation are obtained from Reference 11 and are given below:
• 1.0 for non-biogenic TOG species
8.812 x 10'° for biogenic ISOP
1.3623 x 10" for biogenic OLE^, PARTERP, and ALD2TERP
• 8.6 x 1010 for biogenic OLEOVOV, PAROVOC, and NROVOC
30.0 for NO
46.0 for NO2
64.0 for SO2
1.0 for AERO
28.0 for CO
29
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SECTION 4.0
DATA REPORTING REQUIREMENTS
The draft CERR requires specific data elements to be reported by States to EPA for point, area,
nonroad mobile, onroad mobile, and biogenic source categories. The following sections summarize the
reporting requirements for each of these four major source sectors, as well as biogenic and geogenic
emission source categories. Electronic data transfer options are also discussed. The draft CERR,
including the preamble, is included as Appendix A to this report, and is referenced where appropriate.
Required data elements for States subject to the Section 110 NOX SIP call budgets are listed in the
draft CERR to demonstrate how Section 110 reporting can be coordinated with reporting for other
emissions inventory requirements. The NOX SIP call data reporting requirements support a rulemaking
that establishes NOX emissions budgets for 23 eastern States to decrease the transport of ozone across
State boundaries. States should be aware that this guidance document only addresses the 8-hour ozone,
PM2 5, and regional haze emission inventory requirements of the draft CERR.
4.1 POINT SOURCES
Point sources are large, stationary, identifiable emissions sources that release pollutants into the
atmosphere. Sources are generally defined by State or local agencies as point sources if they annually
exceed a specified pollutant emissions threshold. These thresholds may vary by State, but EPA has
established certain minimum point source thresholds for both pollutant nonattainment areas and
attainment areas.
According to the draft CERR, States should report data for point sources on both an annual and
triennial basis, starting with the 1999 inventory. Point sources are divided into two categories for
reporting purposes: Type A and Type B. Type A sources represent larger point sources and emissions
for these sources are required to be reported every year. Type B sources include those point sources not
reporting under the Type A source requirement. The reporting frequency for Type B sources has been
established as once every 3 years.
The pollutant emission thresholds that define Type A and Type B sources, as well as the data items
required, are listed in Appendix A, Table 2a. The emissions thresholds also vary depending on whether a
point source is located in a pollutant nonattainment area or attainment area (but the data items are the
same regardless of attainment status). It should also be noted that additional stack data elements, while
not required for annual point source reporting, should be reported every 3 years.
4.2 AREA SOURCES
Area sources are smaller sources that do not qualify as point sources under the relevant emissions
cutoffs. Area sources encompass more widespread sources that may be abundant, but that, individually,
release small amounts of a given pollutant. Examples of area sources include dry cleaners, residential
wood heating, autobody painting, and consumer solvent use.
31
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Every 3 years, beginning with the 1999 inventory, States should submit to EPA area source
emissions data representing all relevant area source categories for the entire State. The data items
required for area source reporting are listed in Table 2b of Appendix A.
4.3 NONROAD MOBILE SOURCES
Nonroad mobile sources can be defined as mobile and portable internal combustion powered
equipment not generally licensed or certified for highway use. Nonroad engines can be classified
according to distinct nonroad equipment categories, ranging from small lawn and garden equipment to
heavy-duty construction equipment, large aircraft, and diesel locomotives. These general categories
comprise specific types of applications (e.g., chainsaws, front mowers, and leaf blowers/vacuums are
examples of lawn and garden applications).
Every 3 years, States should submit to EPA a statewide nonroad mobile source emissions inventory,
starting with the 1999 inventory. Table 2c of Appendix A presents the data items required to be reported
for mobile sources (both nonroad and onroad). For nonroad sources, the activity is typically expressed in
terms of horsepower-hours, the amount of fuel consumed, or hours of use (not VMT as listed in Table 2c,
which applies to onroad mobile sources). If States make changes to the default NONROAD model
inputs, discussed in more detail in Section 5.5.3, these input files should be submitted to EPA along with
the nonroad data elements.
4.4 ONROAD MOBILE SOURCES
Onroad mobile sources are defined as those vehicles registered for use on public roadways, and
include automobiles, light-duty and heavy-duty trucks, buses and motorcycles. Onroad emissions are
comprised of both exhaust (i.e.. tailpipe) and non-exhaust (e.g., refueling, tire and brake wear)
components.
States are required to submit a statewide onroad mobile source emissions inventory on a 3-year
basis, starting with the year 1999. Table 2c of Appendix A presents the data items required to be
reported by States for onroad mobile sources. The MOBILE model input files should also accompany
the onroad mobile source data, so that these inputs are available for national and regional air quality
modeling studies.
4.5 BIOGENIC AND GEOGENIC SOURCES
Biogenic and geogenic sources are natural (i.e., nonanthropogenic) emissions sources. Biogenic
sources are biological sources of ozone precursor emissions such as trees, agricultural crops, or microbial
activity in soils or water. VOC and NOX emissions can also result from geological activity, most notably
from seeps of oil or natural gas, volcanoes, and fumaroles (i.e., vapor or gas vents in a volcanic region).
Soil wind erosion is a geogenic source of PM10 and PM25 emissions (although in the past this process has
also been considered to be an anthropogenic fugitive dust component of PM emissions inventories). In
addition, lightning may also be a significant contributor to natural NOX emissions in an inventory area.
Table 2d of the draft CERR specifies the data elements for biogenic and geogenic source reporting.
According to the draft CERR, a baseline biogenic emissions inventory is required to be established
for each State. Triennial updates to this baseline inventory are only required if land use characteristics
used in determining biogenic emissions have changed, or if a new method is used to determine emissions.
To the extent that the EPA develops a biogenic baseline for the specified base year inventory [e.g., using
Biogenic Emissions Inventory System-2 (BEIS-2)], it would be acceptable and practical for a State to use
32
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these EPA-generated emission estimates as the basis for their SIP planning and modeling inventories.
However, States may use non-BEIS-2 estimates if they believe they have more representative data for
estimating biogenic emissions, and can demonstrate better quality emissions data.
The EPA also encourages States to prepare an inventory of all significant geogenic sources in the
inventory area. EPA-generated PM emissions for wind erosion are expected to be available for use by
States in their SIP base year and 3-year cycle inventories, but if other geogenic sources are contributing
to either PM, regional haze, or ozone precursor emissions, these should be inventoried as well.
4.6 DEVELOPMENT OF COMPREHENSIVE EMISSION DATA BASE AT EPA
The EPA is establishing the NET ORACLE data base to store and distribute the EPA's NET
inventory. The NET data base will serve as a central repository for EPA, State/local agencies, and the
general public to access the national inventory to use in air quality modeling, tracking progress in
meeting CAA requirements, setting policy and answering questions from the public. The NET data base
is being redesigned in ORACLE using the data elements and data relationships defined by the EIIP Data
Model, discussed in section 4.7. The NET ORACLE data base is expected to be completed in 1999 and
the NET Input Format is available now.
The EPA has announced that it will be closing out the emissions component of the Aerometric
Information Retrieval System (AERS)/Facility Subsystem (AFS) effective September 30, 2000. States
should anticipate this and are encouraged to develop plans for using the NET data base with their
emission inventory data.
4.7 ELECTRONIC DATA TRANSFER REQUIREMENTS
4.7.1 Overview
To facilitate the transfer of the State-generated inventory data, the EPA has supported the
development of standard data transfer through the EIIP. Electronic reporting of inventory data is an issue
that is dynamic and changing. States should use resources such as EPA's Data Submission section at
http://www.epa.gov/ttn/chief/ei for tracking the latest developments related to emissions reporting.
According to the draft CERR, four basic options for electronic data reporting exist:
EPA NET data base format
• AFS format (for prior source data only)
• EIIP/Electronic Data Interchange (EDI) format
• Direct source reporting for Title FV sources and sources participating in regional NOX trading
programs (e.g., 40 CFR Part 96).
All of these electronic formats will accommodate the data transfer of annual and average summer day
emissions. Note that any State that submits complete data in these formats has met EPA emission
reporting requirements.
These reporting options are discussed in more detail in the sections that follow. If an agency
submits their data in another electronic format (i.e., aside from one of the acceptable formats), EPA may
33
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not be able to enter their data into the EPA system (because of limited resources). In these cases, EPA-
generated default data may be used to represent emissions for the area. In addition, although not listed as
an option in the CERR, the EPA has acknowledged that some State or local agencies may choose to
update the NET data by overwriting the NET distribution file. However, the potential for transcription
errors is high, and, if significant revisions are necessary to improve the EPA NET data, this option is not
recommended.
Note that prior to using the EIIP/EDI data transfer procedure, States should contact EFIG to
determine the status and operating procedure for supporting this option.
4.7.2 EPA NET Input Format
The NET Input Format creates relational, normalized data sets which conform to the relational
standards and structure of the NET ORACLE data base. The relational nature of the format design
enables it to be mapped to a wide variety of data base structures.
The basic steps for data transfer using the EPA NET data base format include:
(1) Map State inventory data to the EPA NET data base format.
(2) Program a conversion utility to translate data in the State's data base to EPA NET data base
input format files, using the mapping scheme developed in Step 1. (Software needed for the
translation could be any data base or spreadsheet program or other data handling system
capable of generating files compatible with the NET file structure. Some States' data storage
systems may be able to be programmed to output stored data in the correct format.)
(3) Use the software developed in Step 2 to translate State's data into EPA NET data base files.
(4) Transfer the EPA NET data base files to EPA/EFIG.
Detailed user documentation for the NET Input Format is available on EPA's Internet web site at
http://www.epa.gov/ttn/chief/ei under "Data Submission." The documentation includes important user
conventions and code tables, as well as format specifications and data submission procedures.
4.7.3 AIRS Format
The AIRS format has been used for electronic reporting for previous inventories and is still the
primary inventory data storage vehicle for several States. Using the AIRS format is a valid method to
make an electronic inventory submittal, but States should be aware that this method of reporting is
limited to point source information. For States that choose to submit point source data via AIRS/AFS, it
will be necessary to use one of the other data transfer options to submit area, mobile, and biogenics data.
To accommodate point source data submittals in the AIRS/AFS format, a utility will be available in
AFS, and used by EPA to translate AFS-formatted data into a NET-compatible format. This will allow
EPA to move point source data from AFS into the NET data base to complete the national emission
inventory for point, area, mobile, and biogenic sources. Further information about how to use AIRS/AFS
can be found on the Office of Air Quality Planning and Standards (OAQPS) Technology Transfer
Network (TTN) web page at the following address: http://www.epa.gov/ttn/airs/.
34
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4.7.4 EIIP/EDI Format
The EIIP has developed a data transfer format using existing EDI standards. Electronic Data
Interchange is a nonproprietary data exchange technique created and maintained by the American
National Standards Institute (ANSI). The EIIP/EDI format can provide a common data exchange format
for federal. State and local government agencies, and eventually for industry, to exchange emissions
inventory information electronically using a single data transfer format.
The EIIP/EDI format was developed and tested as a prototype data transfer demonstration with two
pilot States and EPA. The technical documentation necessary for the EDI data transfer prototype
demonstration may be found on the EIIP web page, under Data Management Committee Procedures
Documents. Also included is the document Results of the EIIP EDI Prototype Data Transfer
Demonstration, which best describes how the EIIP EDI data transfer is accomplished and the purpose of
the different technical documents.
The EDI data transfer procedure may be available to State/local agencies through EPA assistance.
While the EIIP successfully tested the use of EDI through its prototype demonstration, the EPA is
determining how to best establish and support EDI data transfer procedures across the Agency.
The general steps involved in the EIIP/EDI data transfer process are:
(1) Identify a commercially available EDI translator that is compatible with the data application
and local computing system environment. (The initial participants are using the same EDI
translator, provided as part of the EIIP prototype system.)
(2) Program the translator using the EIIP/EDI technical documents. (The programming of the
shared EDI translator is provided as part of the EIIP prototype system.)
(3) Define the loader file format for the translator. (The loader file format for the shared translator
is provided as part of the EIIP prototype system.)
(4) Program a conversion utility to extract and map the State data into the appropriate fields of the
loader file format.
(5) Convert the extract file of State data to an EDI formatted file, using the EDI translator.
(6) Transfer the EIIP/EDI standard format file to EPA.
Inventory data that have been converted to the EIIP/EDI standard format can be made available to
the EPA or any other requestor by sending it on a floppy disk, electronically through Internet E-mail, or
by providing a downloadable file on an Internet file transfer protocol (FTP) site. Prior to using the
EIIP/EDI data transfer procedure, States should contact EFIG to determine the status and operating
procedure for supporting this option.
4.7.5 Direct Source Reporting
Certain point sources may already be reporting electronic emissions data directly to EPA. For
example, electricity-generating units subject to Title IV Acid Rain monitoring and reporting provisions
must report continuous emission monitoring system (CEMS) data in a specified electronic data reporting
(EDR) format to EPA. In addition, large industrial combustion sources participating in regional NOX
35
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mass emissions trading programs (e.g., under 40 CFR Part 96) are allowed to submit data using this
method. This CEMS data may not directly fulfill reporting requirements for all pollutants that would
constitute a State's ozone, PM, or regional haze SIP submittal. However, EPA acknowledges this to be a
viable data option where reporting requirements overlap, and would like to encourage and facilitate the
use of continuous emission monitoring data by States and EPA. One possible option may involve the
calculation of emissions for pollutants not reported under Part 75 or Part 96 (e.g., PM10, PM25) by
applying emission factor ratios to the highly temporally-allocated emission estimates available for other
pollutants such as NOX and SO2.
To avoid duplication of effort, the EPA envisions that these emissions data will either be:
(1) transferred into EPA's central emissions data base after submittal by the source; or (2) if a State
prefers, the data can be made available to States for incorporation into their emissions inventory, which
ultimately will be entered into EPA's NET data base.
4.8 SUMMARY DATA REPORTING
In addition to the detailed emissions data submitted in electronic form, the EPA recommends that
general summaries of the emissions inventory data be compiled and submitted by States. EPA
Headquarters and EPA Regional Offices will use these summaries for easy and efficient comparison with
other States' inventories, and as a check for approximate and valid ranges of emissions. Examples of
statewide emissions summaries are presented in Tables 4.8-1 and 4.8-2. States may also want to consider
summarizing pollutant emissions by county.
Table 4.8-1. Statewide Ozone Precursor Emissions by Source Sector
Source Type
Point Sources
Area Sources
Onroad Mobile Sources
Nonroad Mobile Sources
Biogenic Sources
TOTAL EMISSIONS
VOC Emissions
tons/yr
Ibs/day
CO Emissions
tons/yr
ibs/day
NOX Emissions
tons/yr
Ibs/day
36
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Table 4.8-2. Statewide PM2 5 and Precursor Emissions by Source Sector
Source Type
Point Sources
Area Sources
Onroad Mobile Sources
Nonroad Mobile Sources
Biogenic Sources
TOTAL EMISSIONS
PM2.5
Emissions
tons/yr
VOC
Emissions
tons/yr
NOX
Emissions
tons/yr
SO2
Emissions
tons/yr
NH3
Emissions
tons/yr
37
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SECTION 5.0
EMISSION INVENTORY DEVELOPMENT
5.1 AVAILABLE GUIDANCE
EPA has developed numerous guidance documents to assist State/local agencies in developing
emissions inventories for various pollutants. These include the EIIP guidance documents, AP-42,15 and
older documents such as Procedures for the Preparation of Emission Inventories for Carbon Monoxide
and Precursors of Ozone, Volume A16 These documents can be accessed using EPA's CHIEF web site at
http://www.epa.gov/ttn/chief/. The EIIP guidance documents are EPA's most recent emission inventory
development guidance and should be the primary source of guidance for State/local agencies. In
addition, emission inventory software is available through EPA's State Emissions Inventory Software
Clearinghouse found at the following address: http//www.epa.gov/ttn/airs/afs/reeng/clearhse.html.
For PM. EFIG will be developing a "getting started" web page in 1999. This web page, titled
"PM25 Emission Inventory Resource Center," will be active by summer 1999 and will be available at
http://www.epa.gov/ttn/chief/eiip/pm2.5inventory/. While EIIP is currently developing relevant guidance
material, the "getting started" web site will be prepared and available before these additional materials.
EPA is also evaluating its current projections guidance, Procedures for Preparing Emissions
Projections,^ to determine how it should be updated/revised to reflect the requirements of the new
NAAQS, regional haze, and other programs. State/local agencies should refer to the existing projections
guidance, until new guidance is issued by EPA.
5.2 NATIONAL EMISSION TRENDS INVENTORY
EPA develops the NET inventory every year and will provide it to the States. The NET contains
statewide emission estimates for all of the pollutants and pollutant precursors required by this guidance.
The NET is comprehensive and includes emission estimates for point sources, area sources, mobile
sources, and biogenic sources. EPA believes that some State and local agencies will find the NET to be a
useful tool in preparing their emission inventories required by this guidance. If States choose to use the
NET in their inventory preparation, EPA would suggest the following as a means of prioritizing their
inventory efforts and resources:
• Point Sources - this should be the States' main point of emphasis. The NET point source data
are best for utility emissions since a national data base is available from the Department of
Energy.
• Area Sources - States should review their area source emission estimates in the NET. The
State may want to concentrate their efforts on the large area source categories. In general, the
greatest opportunity for improving the NET area source estimates is for the State or local
agency to develop locally specific activity data.
• Mobile Sources - if State or local agencies choose to use the NET onroad emission estimates as
a starting point, improvements in the estimates can be made by providing locally specific
39
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inputs to the MOBILE model and more precise estimates of VMT. Improvements to the
nonroad estimates can best be made by using the EPA NONROAD model when it becomes
available.
• Biogenic Sources - The NET biogenic estimates are believed to be reliable. However, if State
or local agencies want to improve these estimates, locally specific land use/land cover data can
be obtained.
5.3 POINT SOURCES
Volume II of the EIEP guidance documents includes major chapters that address various combustion,
manufacturing, and production activities that are point sources.18 Information in these chapters should be
used to estimate ozone and PM25 precursor emissions where they address the source categories of
interest. The EIIP point source chapters within Volume II at various States of production are as follows:
• Chapter 2: Preferred and Alternative Methods for Estimating Air Emissions from Boilers
• Chapter 3: Preferred and Alternative Methods for Estimating Air Emissions from Hot-Mix
Asphalt Plants
• Chapter 4: Preferred and Alternative Methods for Estimating Fugitive Air Emissions from
Equipment Leaks
• Chapter 5: Preferred and Alternative Methods for Estimating Air Emissions from
Wastewater Collection and Treatment
• Chapter 6: Preferred and Alternative Methods for Estimating Air Emissions from
Semiconductor Manufacturing Facilities
• Chapter 7: Preferred and Alternative Methods for Estimating Air Emissions from Surface
Coating Operations
• Chapter 8: Preferred and Alternative Methods for Estimating Air Emissions from Paint and
Ink Manufacturing Facilities
• Chapter 9: Preferred and Alternative Methods for Estimating Air Emissions from Metal
Production Facilities
• Chapter 10: Preferred and Alternative Methods for Estimating Air Emissions from Oil and
Gas Field Production and Processes
• Chapter 11: Preferred and Alternative Methods for Estimating A ir Emissions from Plastic
Products Manufacturing
Each industry- or source-specific document contains a brief description; identification of emission points;
an overview of methods available for estimating emissions; example calculations for each technique
presented; a brief discussion on quality assurance and quality control; and the SCCs needed for entry of
the data into a data base management system. The SCCs included in each volume apply to the process
emission points, in-process fuel use, storage tank emissions, fugitive emissions, and control device fuel
40
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(if applicable). More details on PM emission inventories will be available in a "getting started" web site
on PM, available in the summer of 1999.
Table 5.3-1 lists potential point source categories. This table is presented as a guide to aid
State/local agencies in focusing their point source emission inventory efforts, and is based on an analysis
of EPA's NET data base. The table shows where in EPA's data base significant point source emissions
occur. The H (high), M (medium), and L (low) designations indicate the level of significance of a source
category's emissions to the overall emissions of that pollutant. A / indicates that emissions of the
pollutant may occur from that category but are not considered significant. A blank cell indicates that no
emissions of the pollutant were recorded in EPA's NET data base for that source category. Note that
local priorities for inventory development may vary depending on the nature of sources in the area.
State/local agencies should also be aware that some of these source categories may have both point and
area source components, and that they should be careful to avoid double-counting of emissions.
5.4 AREA SOURCES
Area sources are generally described as those sources that are too small, numerous, or difficult to be
inventoried individually. Potential area sources of emissions are given in Table 5.4-1 and potential
crustal (dust) sources of emissions are given in Table 5.4-2. These tables are presented as guides to assist
State/local agencies in focusing their area source emission inventory efforts. The tables are based on an
analysis of EPA's NET data base and show where in the data base significant area source emissions
occur. As with Table 5.3-1, the H (high), M (medium), and L (low) designations indicate the level of
significance of a source category's emissions to the overall emissions of that pollutant. A / indicates
that emissions of the pollutant may occur from that category but are not considered significant. A blank
cell indicates that no emissions of the pollutant were recorded in EPA's NET data base for that source
category. Note that local priorities for inventory development may vary depending on the nature of
sources in the area. State/local agencies should also be aware that some of these source categories may
have both point and area source components, and that they should be careful to avoid double-counting of
emissions.
The EIIP Area Source Committee has issued preferred and alternate emission estimation methods
documents under EIIP Volume III for the following categories:19
• Chapter 2: Residential Wood Combustion
• Chapter 3 Architectural Surface Coating
• Chapter 4: Dry Cleaning
• Chapter 5: Consumer and Commercial Solvent Use
• Chapter 6: Solvent Cleaning
• Chapter?: Graphic Arts
• ChapterS: Industrial Surface Coating
• Chapter 9: Pesticides - Agricultural and Nonagricultural
41
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Table 5.4-1 (continued)
CATEGORY
' SO2 i PM NH3* ! VOC ! NOX CO
1
L
Solvent Utilization (continued) i i i i ! i
Surface Coating _ ___ __ ___ i i i _ i H "__/ _ ' _/
Solvent Utilization NEC ......
Storage and Transport
Bulk Materials Storage
Bulk Terminals and Plants
Organic Chemical Storage
Petroleum and Petroleum Product Storage
Petroleum and Petroleum Product Transport
Service Stations: Breathing and Emptying
Service Stations: Stage I
Service Stations: Stage II
i
i
i i i / i i i
4 4 4 -4------\ -I-
i i i i M i i
4 4 4 4---4 4-
i i i i L i i
4 4 4 4- ---4-—-|-
i i i i L i / i
4 4 4 4------f -I-
i i i i L i i
i i i i L i i
i i i i H i i
4 4 4 -4---—f H-
I I ! I H ! !
Waste Disposal and Recycling
Incineration
Industrial Waste Water
Landfills
i
i i
i i
[. ^ [ [—_ j. (
I i I i L I I
| j. |___ ^___ |_____^____.
Open Burning
P~OTWs
~T~SDFs
Other
i
i
i
I I I
4..r._4__,..4 _J4-4-U~^-
4—4 4.^.44.4 4 .
i i i i L i / i /
4 4 4 4 __ 4 4
i I i i L ! I
Miscellaneous i i i
i i i i i i
Agriculture and Forestry ! ! L ! H ' M I I
Catastrophic/Accidental Releases i i i i L i i
r \ 1. ^ ^ ^ 1
Health Services i i i i / i i
Other Combustion (Structure Fires, Forest Fires, Slash ] L j H j j H j M j H
Burning, Prescribed Burning, Managed Burning) ! ! J ! ! !
* The emissions from all NH3 source categories need to be better characterized because of their role in the formation
of secondary particles.
Note: The H (high), M (medium), and L (low) designations indicate the level of significance of a source category's
emissions to the overall emissions of that pollutant.
A / indicates that emission of that pollutant may occur from that source category, but they are not
considered significant.
A blank cell indicates that no emissions of that pollutant are emitted from that source category based on the
data in EPA's NET inventory.
45
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Table 5.4-2. Crustal Sources of Emissions
CATEGORY
Natural Sources
Geogenic, Wind Erosion
Miscellaneous
Agricultural Crops (Tillage)
Construction
Paved Roads
Unpaved Roads
Other Fugitive Dust (e.g., Mining and Quarrying)
voc
NOX
h-M, -„.,
1
S02
1
1 1
CO
PM
M
h.._|
M
M
M
H
L J
M
NH3
Note: The impact of crustal sources on PM2 5 ambient concentrations is much lower than would be suggested by
their estimated emissions (relative to other directly emitted PM25).
The H (high) and M (medium) designations indicate the level of significance of a source category's
emissions to the overall emissions of that pollutant.
• Chapter 11: Gasoline Marketing
• Chapter 12: Marine Vessel Loading, Ballasting, and Transfer
• Chapter 13: Autobody Refinishing (currently available as a draft; to be revised in 1999)
• Chapter 14: Traffic Paints
• Chapter 15: Municipal Landfills
• Chapter 16: Open Burning (available as a draft)
• Chapter 17: Asphalt Paving
The EUP Volume III, Chapter 1 document lists potential activity data sources by category.
Procedures for the Preparation of Emission Inventories for Carbon Monoxide and Precursors of Ozone,
Volume 1 (Reference 16) also gives detailed guidance for estimating ozone precursor emissions from area
sources. Agencies should review the EIIP documents carefully for information on the types and sources
of data needed to develop emissions estimates for each source category. Table 5.4-1 lists the area source
categories that EPA believes are significant sources for the pollutants in the table.
5.5 MOBILE SOURCES
Mobile sources consist of both highway vehicles (cars and trucks) and nonroad mobile sources (e.g.,
airplanes, motorboats, farm equipment, etc.). Table 5.5-1 lists mobile source categories that EPA
believes are significant sources of emissions. This table can be used as a guide to assist State/local
agencies in focusing their mobile source emission inventory efforts, and is based on an analysis of EPA's
46
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NET data base. The H (high), M (medium), and L (low) designations indicate the level of significance of
a source category's emissions to the overall emissions of that pollutant. A / indicates that emissions of
the pollutant may occur from that category but are not considered significant. A blank cell indicates that
no emissions of the pollutant were recorded in EPA's NET data base for that source category. Note that
local priorities for inventory development may vary depending on the nature of sources in the area.
Table 5.5-1. Mobile Sources of Emissions
Highway Vehicles
Light-Duty Gas
Light-Duty Gas
CATEGORY
Vehicles and Motorcycles
Trucks
Heavy-Duty Gas Vehicles
Oft-
Diesels
Highway
Nonroad Gasoline
Nonroad Diesel
Aircraft
Marine Vessels
Railroads
i
1
i
i
i
— — 1._
i
— — |._
i
L
r
i
i
i
i
i
i
L
r
i
L_
— r
L
— r
i
i
i
S02 PM NH
i i
M ! M ! IV
3* | VOC NOX
H ! H
. _L H 1 H
MiMiMlHTH
-L- 4-L 4 L
M J H J "L
__L. 4_M
ji4-H-4~ "
-L- 4 M 4 "
M 7 M 7 L
M M L
H . M
T 77 ~r 77
i i
i
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— r -7 — r ~~T~"
- 4 H 4 H
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— r ~r — ' — ..""
L i M
— — _ -j.
i L H
1
1
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1
1
J
1
1
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1
1
1
1
1
1
1
l
— r-
i
CO
H
H
M
M
H
M
M
L
L
* The emissions from all NH3 source categories need to be better characterized because of their role in the formation
of secondary particles
** While NH3 emissions may occur from these source categories, at this time EPA does not have the capability to
make an estimate of these emissions.
Note: The H (high), M (medium), and L (low) designations indicate the level of significance of a source category's
emissions to the overall emissions of that pollutant.
The following sections discuss the models and data sources for onroad mobile sources and nonroad
mobile sources, respectively.
5.5.1 Onroad Mobile Sources
Onroad mobile source populations are typically characterized according to the following vehicle
categories:
• Light-duty gasoline vehicles (LDGV);
• Light-duty gasoline trucks I (LDGT1);
• Light-duty gasoline trucks II (LDGT2);
• Heavy-duty gasoline vehicles (HDGV);
• Light-duty diesel vehicles (LDDV);
Light-duty diesel trucks (LDDT);
• Heavy-duty diesel vehicles (HDDV); and
• Motorcycles.
47
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Ozone precursor emissions for onroad sources are estimated using the MOBILE emission factor
model developed by EPA's Office of Mobile Sources (OMS). In general this model generates emission
factors to apply to VMT estimates for each of the above vehicle categories. PARTS is an emission factor
model developed by OMS to estimate onroad emissions for PM10, PM, 5, and SO^. The use of VMT
activity data and both of these onroad mobile emission factor models are discussed further below.
VMT Activity Data
Each State's highway or transportation agency provides annual data to the FHWA's Highway
Performance Monitoring System (HPMS). The FHWA uses the data provided by the States to report the
condition of the nations' highways to Congress. The HPMS compiles VMT at the State level for rural,
small urban, and individual urbanized areas by 12 different road types, and six distinct vehicle types.
Updated guidance for converting HPMS VMT data to the vehicle classes contained within MOBILESa is
provided by the EIIP in section 2.0 of the report, Use of Locality Specific Transportation Data for the
Development of Mobile Source Emission Inventories.20 This report also contains sections addressing
improvements to travel demand model outputs. In 1993, FHWA issued a letter indicating that all urban
areas greater than 50,000 population should have individual HPMS sample panels representative of travel
within those areas.
EPA guidance, Procedures for Emission Inventory Preparation - Volume IV: Mobile Sources,21
provides a very detailed discussion of HPMS and travel demand models (TDM). Pages 62 to 94 of this
document discuss how to use HPMS data and the more limited cases when TDMs may be used. In
general. HPMS is the preferre 1 method for estimating historical VMT and TDMs are the preferred
method for allocating VMT to the county level and road classes and for calculating growth factors for
future years. The guiding principal of this policy is that the State should provide the same estimate of
travel to the EPA as it uses internally and provides to the FHWA.
In the unusual circumstance that the State believes that an alternative to HPMS provides a better
estimate of historical VMT, the State should write a letter for inclusion in the SIP to that effect to both
EPA and the FHWA signed by the appropriate authorities, normally the State Department of
Transportation, local metropolitan planning organizations, and the State environmental agency
responsible for submitting the SIP. The letter should document why the State believes its proposed
alternative is superior to HPMS for purposes of estimating historical VMT. The letter should also
address the following three issues:
• How the State proposes to create a historical record, at least back to 1990, so that the SIP
planning elements are internally consistent, in the event that the State proposes to substitute its
alternative approach when satisfying the requirements associated with the 1-hour standard;
• How the State plans to assure that the statistical design and funding level of the alternative
program are stable for an extended period of time to assure that the proposed methodology will
continue to be available for conformity and other analyses; and
• The frequency at which the State plans to update its historical VMT estimates to accommodate
the reporting requirements of the various SIP elements and transportation planning processes.
The approval of the use of any alternative to HPMS will be made by the EPA Regional Office.
States are encouraged to identify in their IPP their proposed method for determining historical VMT, for
allocating VMT to the county level and road classes, and for calculating growth factors for future years.
48
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MOBILES Model
Onroad mobile source VOC, NOX, and CO emission factors are calculated using the MOBILE5a
model. MOBILESa generates exhaust and evaporative emission factors in grams per mile. These factors
are then applied to the VMT activity estimates, discussed above.
Although MOBILE5b was released as an interim update to the MOBILE5a model during August
1997, States are not required to use MOBILESb. States can continue to use either MOBILE5a or
MOBILE5b until the time that MOBILE6 becomes available. This applies to SIP inventories and
modeling, conformity determinations, and the quantification of emission reductions for open market
trading purposes. The MOBILE5a and MOBILESb models, user's guides, and associated documentation
are all available at EPA's OMS web page at http://www.epa.gov/oms/m5.htm. Guidance concerning the
use of MOBELE6 versus MOBILES for preparing the 1999 and projected emission inventories for ozone
and PM SIPs will be issued by OMS after it is determined how all final updates to MOBILE6 emission
factors will affect pollutant emissions inventories. States also have the option of using their own mobile
source emission factor model if they have coordinated its use with OMS.
Although the MOBILE6 model is not yet available, many of the optional local MOBILES inputs are
also expected to be used in MOBILE6. To this end, States should plan for compiling a 1999 onroad
inventory using MOBILE6 by developing the best possible set of local inputs for variables such as
registration distribution, I/M program inputs, defining the geographic and temporal applicability of other
control programs (e.g., in which counties and what months is oxygenated fuel used), mileage
accumulation rates, and determining what temperature data will be used for each of the different types of
inventories. It is also recommended that States have methods in place for 1999 for determining fuel
characteristics throughout the State and according to season, including fuel Reid vapor pressure (RVP),
sulfur level, oxygen content, and the makeup of reformulated gasoline. For all types of onroad vehicle
emission modeling (e.g., ozone modeling, 3-year cycle inventories, transportation conformity), having an
accurate, local registration distribution is important to determining accurate emission inventories.
Because wide differences between actual model year fleet distributions and default distributions in the
MOBILE model have been observed, States are encouraged to use county-specific motor vehicle model
year distributions obtained from their State motor vehicles office. For the 3-year cycle and modeling
inventories, having accurate representations of control programs in place during the modeled time
periods is crucial, particularly for I/M program modeling. For example, if a set of phase-in cutpoints are
being used in an I/M program in 1999, it is important to model that set of cutpoints rather than the final
set of emission cutpoints. On the other hand, for attainment demonstration or projection inventories,
where allowable emissions are calculated, the final planned I/M program may be modeled. Modeling
accurate speeds by roadway type, while important for all inventory types, is particularly important in
transportation conformity modeling. In this case, it is necessary to capture the changes in average speeds
by roadway type or roadway link due to the presence or absence of particular transportation-related
programs.
Procedures for Emission Inventory Preparation, Volume IV: Mobile Sources (Reference 21)
provides recommendations for determining appropriate values for MOBILE model inputs such as
ambient temperature and speed. EPA encourages the use of non-default inputs by users of the MOBILE
model, but requests that States discuss the selection of any non-default values in documentation
submitted with the onroad mobile source emission inventory.
Several months before the final release of MOBILE6, OMS will make available a working beta
version of MOBILE6 to obtain user feedback on program operation. To allow stakeholder and peer
review of proposed model changes, OMS has posted background reports to describe the various inputs
49
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and assumptions used within MOBILE6, available at the following address:
http://www.epa.gov/oms/m6.htm. Examples of changes that are likely to be implemented for the final
MOBILE6 model include:
• incorporate effects of non-FTP, or "off-cycle," driving patterns on emissions;
• update heavy-duty engine emission conversion factors, including brake specific fuel
consumption (BSFC), fuel economy, non-engine fuel economy improvements, and fuel
densities;
• expand emission factor calculations for four distinct subcategories of HDDVs similar to
PARTS model;
• update evaporative emissions to incorporate real-time diurnal emissions estimates, as well as
improving hot soak, resting loss, and running loss emissions;
• evaluate effects of fuel characteristics on emissions, including in-use sulfur content and
oxygenates; and
• update default fleet characterization data (registration distributions and average annual mileage
accumulation rates by vehicle type.).
The MOBILE6 web page also lists public workshops being held on MOBILE6.
PARTS Model
PARTS is a model that estimates in-use paniculate air pollutant emissions (i.e., PM10, PM25, and
SO2) for gasoline and diesel-fueled vehicles and gives emission factors in grams per mile. The model
contains emission factors corresponding to exhaust paniculate emissions, exhaust paniculate
components, brake wear, tire wear, and reentrained road dust. PARTS contains default values for the
majority of the emission factor calculations, but also allows for user-supplied data for certain inputs. For
the vehicle registration distribution, PARTS uses the same vehicle classifications as the MOBILE model.
except that the MOBILE HDDV class is divided into five subclasses in PARTS (see Table 5.5-2). One
potential method for developing the vehicle distribution for PARTS may be to use the MOBILE model
vehicle class distribution, and apportion the value for MOBILE HDDV among the five PARTS HDDV
subclasses using HDDV sales data, survival rates, and diesel market shares. As indicated in section
5.5.2, MOBELE6 and PARTS vehicle classes may be identical in the future.
Details concerning the inputs to be supplied to the PARTS program are included in the PARTS
user's guide. States can download electronic copies of the user's guide, as well as the most recent
version of the PARTS model from the OMS web page at the following address:
http://www.epa.gov/oms/part5.htm. OMS plans to update PARTS by issuing a PART6 model after
MOBDLE6 is released. When updated, the PART6 vehicle classes are likely to be identical to vehicle
classes in MOBELE6. In addition, PART6 will reflect any available updated emission factor data
developed by OAQPS. For example, the AP-42 emission factor section for unpaved roads has been
revised, and this latest information will be incorporated into PART6.
50
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Table 5.5-2. PARTS Vehicle Classes
Vehicle
LDGV
LDGT1
LDGT2
HDGV
MC
LDDV
LDDT
Class
light-duty gasoline vehicles
light-duty gasoline trucks, I
light-duty gasoline trucks, II
heavy-duty gasoline trucks
motorcycles
light-duty diesel vehicles
light-duty diesel trucks
2BHDDV class 2B heavy-duty diesel vehicles
LHDDV
MHDDV
HHDDV
BUSES
light heavy-duty diesel vehicles
medium heavy-duty diesel vehicles
heavy heavy-duty diesel vehicles
buses
FHWA
Class
1
2A
2B-8B
1
2A
2B
3,4,5
6,7,8A
8B
Gross Vehicle
Weight (Ibs)
<6,000
6,001-8,500
>8,500
<6,000
6,001-8,500
8,501-10,000
10,001-19,500
19,501-33,000
33,000+
5.5.2 Nonroad Mobile Sources
The EPA's QMS is developing a computer model, NONROAD, to directly estimate pollutant
emissions in tons for the following nonroad equipment categories:
• Lawn and Garden
- residential
- commercial
• Construction and Mining
• Agricultural
• Industrial
• Airport Service
• Recreational Vehicles
Logging
• Recreational Marine
• Light Commercial
• Railway Maintenance
Within these general categories are more specific types of equipment (e.g., 2-wheel tractors, balers,
and combines are examples of 10-digit SCCs within the broader 7-digit SCC defining agricultural
equipment). Because of the variations in hours of use, horsepower, and load factors corresponding to
engines in various applications, these distinctions are necessary. These applications can be further
classified according to fuel and engine type [diesel, gasoline 2-stroke, gasoline 4-stroke, compressed
natural gas (CNG), and liquid petroleum gas (LPG)].
The NONROAD model estimates emissions for six exhaust pollutants: hydrocarbons (HCs), NOX,
CO, PM, SO2, and CO2. Hydrocarbons can be reported as total hydrocarbons (THC), TOG, nonmethane
organic gases (NMOG), NMHC, or VOC. Paniculate matter can be reported as total PM, PM10 (which is
equivalent to total PM), or PM2 5. The model also estimates non-exhaust HC emissions, including
crankcase, diurnal, and refueling emissions. The model allows the user to report total HC emissions,
51
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which account for both exhaust and relevant non-exhaust components (depending on the engine type and
pollutant). At the present time, reliable nonroad NH3 emission factors are not available, and the
NONROAD model does not generate nonroad NH3 emissions. The EPA anticipates that NH3 emission
factors for nonroad may be available by 2002.
NONROAD allows the calculation of pollutant emissions at the national, State, and county level.
The model can also estimate sub-county (i.e., nonattainment area) emissions if the necessary inputs to
perform this calculation are supplied by the user. By using estimates of annual activity for each
equipment type, annual emissions inventories can be calculated. Additional inventories can be calculated
on a seasonal (i.e., summer, fall, winter, spring), monthly, or daily (i.e., week or weekend day) basis by
allocating annual activity to these smaller time periods. Past year, present year, and future year
inventories (up to the year 2050) can be generated with this model.
The NONROAD model estimates emissions for each specific type of nonroad equipment by
multiplying the following input variables:
• Equipment population for a specified year, distributed by age, horsepower, fuel type, and
application;
• Average load factor expressed as average fraction of available power;
• Activity in hours of use per year; and
• Emission factor, accounting for engine deterioration and any applicable new standards.
The emissions are then temporally and geographically distributed using appropriate allocation
factors.
States have the option of replacing default model values with more representative data if available.
If a State makes changes to default model values such as local equipment populations, geographic
allocations, and local growth rates, States should submit the input files to EPA, as well as a description
and justification of why the defaults were changes. However, EPA does not recommend that
NONROAD users change values for certain model variables, including useful life and scrappage, activity
data (i.e., load factors and hours of use), and emission deterioration factors. This is largely because all of
these variables are related to and affect the overall engine scrappage function. If one of these variables
changes, other variables should be adjusted accordingly. The EIIP has published a report entitled,
Guidance for Estimating Lawn and Garden Activity Levels22 that discusses methods for improving
estimates of local lawn and garden equipment populations according to commercial and residential use.
The OMS has posted technical reports on their web site that describe the various default input
variables. Copies of these reports, as well as the most recent version of the NONROAD model
(including user's guide) can be downloaded from the web site: http://www.epa.gov/oms/
nonrdmdl.htm#model. In addition, a CD-ROM copy of the model can be obtained from OMS by request.
Commercial Marine Vessels, Aircraft, and Locomotives
The first final version of the NONROAD model will not provide States with a tool for estimating
emissions for commercial marine, aircraft, and locomotives. For further guidance on developing
emission estimates for these nonroad categories, States are referred to EPA guidance, Procedures for
Emission Inventory Preparation, Volume IV: Mobile Sources. Emission factors will ultimately be
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available in a revised version of Section II of the 5th edition of AP-42, Volume II. The completion date
for this new AP-42 section is uncertain, but when complete, the emission factors will be posted at the
following web site address: http://www.epa.gov/oms/ap42.htm. In the interim, those seeking updated
nonroad mobile source emission factor information should direct inquiries to Mr. Greg Janssen of EPA's
QMS, at (734) 214-4285; e-mail: janssen.greg@epa.gov. Following is a discussion on the status of
preparing updated guidance for commercial marine, aircraft, and locomotive categories.
The OMS originally intended to incorporate a commercial marine module into the first version of
the NONROAD model. However, due to unexpected complications in developing input data and the
requisite computer code, OMS will discontinue work on the electronic commercial marine module for the
NONROAD model, and concentrate instead on written guidance. This guidance may provide "best
estimate" default emissions inventories for approximately 150 ocean, lake, and river ports, but may allow
for the use of more accurate, locally-specific emissions data if available to the user. The electronic
commercial marine module will be reconsidered for a subsequent update of the NONROAD model.
For aircraft, activity data in the form of landing and take-offs (LTO's) can be obtained from the
Federal Aviation Administration (FAA). The Federal Aircraft Engine Emission Data Base (FAEED),
developed by the FAA and EPA, is a tool for calculating aircraft emissions. This data base is a
stand-alone application that allows a user to compute pollutant emissions produced by a specified fleet.
However, users should be aware that emission factor data for newer engine models are not available in
this version of the FAEED. EPA's OMS will continue to work with the FAA to potentially develop an
updated emissions estimation data base that reflects emissions data for all engine types, and may also
provide the necessary activity data. The FAEED is available at EPA's OMS web site.
For locomotives (especially Class II and Class III line haul and yard operations), the majority of the
activity data are obtained by directly contacting individual railroads in the inventory area. Written
guidance for estimating locomotive emissions will be prepared by OMS after further investigating input
data availability.
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5.6 BIOGENIC AND GEOGENIC SOURCES
Biogenic and geogenic sources contribute to pollutant emissions as indicated in Table 5.6-1.
Table 5.6-1. Natural Source Categories and Pollutants Emitted
Source
Biogenic
- Vegetation
- Soil Microbial Activity
Geogenic
-Oil and Gas Seeps
-Wind Erosion
Other Natural
- Lightning
- Stratospheric Injection*
- Oceans*
Pollutant
VOC
/
/
NOX
/
/
/
/
PM10
/
PM2.5
/
* NOX emissions from each of these sources contribute 2 percent or less of the total global NOX
budget, and will not be d'scup^ed further.
5.6.1 Biogenic Sources
Biogenic sources are a subset of natural emissions sources that may contribute significantly to an
emissions inventory. Vegetation (i.e., forests and agriculture) is the predominant biogenic source of
VOC and is typically the only source that is included in a biogenic VOC emissions inventory. Microbial
activity in the soil contributes to natural biogenic NOX emissions.
States are referred to the EIIP document, Volume V, Biogenic Sources Preferred Methods,23 for a
detailed description of some of the biogenic source emissions that should be considered when preparing
an emissions inventory. One of the major constituents of biogenic emissions, isoprene, is highly
photoreactive. Because of this characteristic, inclusion of biogenic emissions is deemed essential for
photochemical air quality modeling for ozone. In addition, some biogenic VOC may ultimately
contribute to secondary particle formation, and would therefore be important with respect to a PM or
regional haze inventory. Computer models available for States to estimate speciated biogenic emissions
include the following:
BEIS-2;
The Personal Computer version of the BEIS-2.2 (PCBEIS-2.2); and
• Biogenic Model for Emissions (BIOME).
The BEIS-2 model and PCBEIS-2.2 can be used to estimate speciated VOC emissions from
vegetation, as well as NOX emissions from soils. BIOME can be used to estimate speciated VOC
emissions from vegetation.
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The BEIS-2 is a stand-alone processor that produces biogenic estimates for use with several existing
air quality models, including the Urban Airshed Model (UAM), Regional Oxidant Model (ROM) and
RADM. As such, the model is the preferred method for generating biogenic estimates required for air
quality modeling. The BEIS-2 model also estimates biogenic emissions from soil, which may be a
significant source of NOX emissions in rural areas. PCBEIS-2.2 output is typically used only for
inventory reporting purposes [and in some cases for Empirical Kinetic Modeling Approach (EKMA)
runs]. Other alternative (but less preferable) methods for estimating biogenic emissions are also
discussed in Volume V of the EIIP document.
Although States are encouraged to develop their own independent biogenic emission estimates, the
EPA will allow States to use EPA-generated BEIS-2 emission estimates as the basis for their SIP
planning and modeling inventories. States should note that biogenic emissions are required in a
projected year inventory. However, unless there are anticipated changes in land use or vegetation
patterns for the modeling area, it is appropriate to assume that biogenic emissions will remain the same
between the base year and projected year. It is expected that the output from BEIS-2, as well as any
updates to this emissions model, will be compatible as input to the planned regional air quality model,
MODELS3.
EPA is updating the BEIS-2 model and plans to release BEIS-3 in late 1999. BEIS-3 will be based
in part on data collected for the Ozark Isoprene Experiment, and is expected to generate lower emission
estimates than BEIS-2 for some areas due to adjustments in estimates of ground cover vegetation. In
addition, EPA recently updated PCBEIS-2.2 with the release BEIS-2.3. Further details on the status of
biogenic emissions modeling are available at EPA's web page at
http://www.wpa.gov/asmdnerl/biogen.html.
5.6.2 Geogenic and Other Natural Sources
Geogenic emissions are primarily the result of oil or natural gas seeps and soil wind erosion. In
addition, lightning may also be a significant contributor to natural NOX emissions in an inventory area.
Volcanoes and fumaroles (i.e., vapor or gas vents in a volcanic region) can be additional sources of
geogenic emissions.
As a source of ozone precursor emissions, geogenic sources are less significant than biogenic
sources. However, geogenic wind erosion can contribute substantially to PM emissions in an area. As
indicated in Section 4.5, EPA typically generates PM10 and PM25 emissions for wind erosion, and these
estimates are expected to be available for use by States in their SIP base year and 3-year cycle
inventories. At this time, the emission estimation methodology for wind erosion is being refined by EPA
to produce more representative PM estimates for this category.
States should also prepare an inventory of all other significant geogenic sources in the inventory
area. Methods for estimating VOC emissions from oil and gas seeps, as well as NOX emissions from
lightning, are described in the EIIP document, Volume V, Biogenic Sources Preferred Methods. For oil
and gas seeps, the preferred method is to develop a local emission factor based on the study of oil or gas
seeps in the inventory area. The document also describes an alternative method developed by the
California Air Resources Board (CARB)24 that includes simplifying assumptions for oil or gas seeps
whose specific flow rates and volatile fractions have not been studied and are not known.
Lightning produces NO, which is oxidized to NO2 in the presence of ozone or in a photochemically
reactive atmosphere. Because lightning is not a direct source of NO2, accounting for this source category
is more important for air quality modeling purposes than for SIP inventory purposes. NO emissions from
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lightning can be estimated by collecting activity data on the cloud-to-ground (CG) lightning flashes,
assuming a frequency of intra-cloud (1C) flashes based on the value for CG lightning flashes, and
applying appropriate emission factors (in molecules NO per flash) to these activity levels.
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SECTION 6.0
QUALITY ASSURANCE/
DOCUMENTATION OF THE INVENTORY
6.1 QUALITY ASSURANCE
As part of the 8-hour ozone NAAQS, PM25 NAAQS, and regional haze rule, States will be required
to perform QA checks and procedures on their inventories. States can develop and select the QA
procedures they will perform, and should include the details of their QA program (including specific
procedures) in their IPPs.
The purpose of QA is to ensure the development of a complete, accurate, and consistent emission
inventory. A well-developed and well-implemented QA program fosters confidence in the inventory and
in any resulting regulatory and/or control program.
The overall QA program consists of two components: QC and external QA activities. Quality
control is a system of routine technical activities designed to measure and control the quality of the
inventory as it is being developed. The QC system provides routine and consistent checks and
documentation points in the inventory development process to verify data integrity, correctness, and
completeness; identifies and reduces errors and omissions; maximizes consistency within the inventory
preparation and documentation process; and facilitates internal and external inventory review processes.
Quality control activities include technical reviews, accuracy checks, and the use of approved,
standardized procedures for emission calculations, and should be included in inventory development
planning, data collection and analysis, emission calculations, and reporting.
External QA activities include a planned system of review and audit procedures conducted by
personnel not actively involved in the inventory development process. The key concept in the QA
activities is an independent, objective review by a third party to assess the effectiveness of the internal
QC program and the quality of the inventory, and to reduce or eliminate any inherent bias in the
inventory process.
An effective QA program includes planning, numerous QC checks during the inventory development
process, and QA audits at strategic points in the process. EPA has developed several guidance
documents designed to assist State/local agencies in designing and implementing their QA programs.
The EIIP Volume VI address QA issues, including the following:3
• Chapter 1: Introduction - The Value ofQA/QC
• Chapter 2: Planning and Documentation
Chapter 3: General QA/QC Methods
• Chapter 4: Evaluating the Uncertainty of Emission Estimates
Chapter 5: Model QA Plan
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These documents can be downloaded fromEIIP's web site at http://www.epa.gov/oar/oaqps/eiip/.
Additional EPA QA guidance is found in the following documents:
• Guidance for the Preparation of Quality Assurance Plans for Oy'CO SIP Emission
Inventories25
• Quality Assurance Program for Post-1987 Ozone and Carbon Monoxide State Implementation
Plan Emission Inventories26
• Quality Review Guidelines for 1990 Base Year Emission Inventories21
Section 4.0 of this document provides State and local agencies with information on how to submit
their data to EPA. Once EPA receives these data, the data will undergo an interim processing step as
EPA performs automated QA checks on the submitted data. The data that pass these checks will be
entered into the NET. EPA will inform a State or local agency when data it has submitted have not
passed the automated checks. State and local agencies will be given the opportunity to correct and
resubmit these data to EPA.
To assist State and local agencies in the QA process, EPA will make available to these agencies the
QA checks that EPA will run on their submitted data. States may decide to pre-screen their data using
these QA checks prior to submitting their data to EPA.
6.2 DOCUMENTATION OF THE INVENTORY
The written presentation to support an emissions inventory submittal for the ozone and PM25
NAAQS, as well as the regional haze rule, should contain documentation that is sufficiently detailed for
EPA to evaluate how the emission inventory was prepared. The EPA requires that States prepare
adequate documentation; the level of detail required in the documentation should be agreed upon with the
Regional Office and specified in a State's Inventory Preparation Plan. This section refers to prior
guidance issued by EPA to assist in developing appropriate documentation for emission inventories.
Written documentation of calculation, assumptions, and all other activities associated with
developing the emission estimates is a key element of the QA program. Documentation of the work that
is actually performed during inventory development includes documentation of calculations (hand
calculations, spreadsheets, and data bases), documentation of the QA program implementation, and
documentation of the results (the inventory report). Examples of topics requiring good documentation in
the inventory development process include:
• point/area source cutoffs to demonstrate that double-counting of emissions does not occur
• point source information on survey mailout procedures, tracking and logging of returned
surveys, and verification procedures for source test data
• adjustments made to source test data to represent longer periods of time, seasonal influences,
etc.
• data obtained from permit and compliance files
• adjustments made for applicable rules, including control efficiency, RP, and RE
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• information obtained on emission factors and activity data (primarily for area sources)
• data references
• adjustments made for local conditions and assumptions made to adjust for scaling up emissions
to account for nonreported sources
• VMT. traffic speeds, miles of roadway for each roadway class, hot- and cold-start percentages.
vehicle age distribution, etc., for the mobile source documentation
Chapter 2 of the EIIP's Volume VI, titled Planning and Documentation provides valuable, detailed
guidance on documenting inventory components.
For a complete example of how an inventory should be compiled and documented. States are
referred to the document. Example Documentation Report for 1990 Base Year Ozone and Carbon
Monoxide State Implementation Plan Emission Inventories.2^ This document provides States with a list
of elements deemed to be essential for documenting an emissions inventory in written form. An outline
for the organization and content of a State's inventory report is presented in Table 6.2-1. This table
references another document entitled Example Emissions Inventory Documentation for Post-1987 Ozone
State Implementation Plans.29 This document also addresses inventory documentation requirements, but
was not explicitly designed to address 1990 inventories. However, much of the guidance provided for
post-1987 inventories would still be applicable for inventories developed for the new ozone and PM,5
NAAQS, and regional haze rule. In addition, although these documents focus on ozone precursor and
CO emission inventories, the principles defined in these reports would also apply to PM and regional
haze inventories.
Another guidance document, Quality Review Guidelines for 1990 Base Year Emission Inventories
presents review guidelines for State and local agencies to use as a self-check prior to submitting the
inventories they prepare to EPA. This document presents checklists for States to use to verify that
effective QC and QA practices are applied to an inventory during the process of developing and
documenting an emissions inventory. EPA does not intend to use this document to determine whether or
not to approve a State's inventory submittal. As stated in Section 2.5, Inventory Approval, the inventory
approval process will be negotiated between the EPA Regional Office and the State. Rather, EPA
believes that the checklists represent sound practice and will be a useful tool in the development of a
State's inventory.
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Table 6.2-1. Outline for Format/Contents for SIP Emission Inventory Reports
I. Cover and Title Page
A. Title (geographic area, type of inventories, pollutants, base year)
B. Responsible agency
C. Report date (date completed/distributed)
D. Preparer (if different from responsible agency - e.g., contractor)
II. Table of Contents
A. Contents
B. Tables
C. Figures
III. Introduction
A. Reason for report being prepared, purpose
B. Geographic area covered, base year, type of inventory (ozone SIP, PM SIP, Regional
Haze), pollutants included (VOC, NOX, CO, SO2, PM10l PM25l NH3)
C. Brief discussion cf contents of report
D. Discussion of automated data systems used
E. Major problems, deficiencies, portions of inventory not included
F. List of primary guidance documents and references used (EPA guidance documents,
BMP documents, AP-42, etc.)
G. List of contacts for each distinct portion of the inventory
IV. Summary
A. Emissions (annual and seasonal) of each pollutant by major category
B. See example tables and graphics given in Example Emissions Inventory
Documentation for Post-1987 Ozone State Implementation Plans (EPA-450/4-89-
018)
V. Documentation of Emissions Methods/Data Estimates
A. Stationary Point Source Emissions
1. discussions of procedures and methodologies
2. example surveys/questionnaires
3. list of plants by primary product and total emissions
4. point source emissions summary
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Table 6.2-1 (continued)
B. Stationary Area Source Emissions
1. discussion of procedures and methodologies
2. list of source categories and emissions
3. calculations and discussion for each source category
4. area source emissions summary
C. Mobile Source Emissions
1. Nonroad Mobile Sources
a. same information as for stationary area sources
2. Onroad Vehicles
a. mobile model inputs and outputs
b. VMT estimates
c. documentation (can put all or part in Appendices)
d. mobile source emissions summary
e. discussion of procedures and methodologies
VI. Quality Assurance/Quality Control (QA/QC)
A. QA/QC plan - discussion of QA/QC methodologies used
B. Results
C. QA procedures can also be discussed in individual source category sections
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SECTION 7.0
REFERENCES
1. Implementation Guidance for the Revised Ozone and Paniculate Matter (PM) National Ambient Air
Quality Standards (NAAQS) and the Regional Haze Program, U.S. Environmental Protection
Agency, Research Triangle Park, NC, 1998.
2. Introduction to the Emission Inventory Improvement Program, Volume I, U.S. Environmental
Protection Agency, Research Triangle Park, NC, July 1997.
3. Quality Assurance/Quality Control, Volume VI, EHP, U.S. Environmental Protection Agency,
Research Triangle Park, NC, 1997.
4. Guidelines for Estimating and Applying Rule Effectiveness for Ozone/CO State Implementation Plan
Base Year Inventories, EPA-452/R-92-010, U.S. Environmental Protection Agency, Research
Triangle Park, NC, November 1992.
5. The 1985 NAPAP Emissions Inventory: Development of Temporal Allocation Factors, EPA-60Q/7-
89-010d, U.S. Environmental Protection Agency, Research Triangle Park, NC, April 1990.
6. ARC/INFO User's Guide: Map Projections and Coordinate Management, Concepts and
Procedures, and ARC/INFO, Command References: ARC™ Command References, Commands 3-Z
(PROJECT).
7. Russell, A.G., R. McNider, J. Moody, and J.G. Wilkerson. Emissions Modeling Protocol-
Meteorological, Emissions and Air Quality Modeling for an Integrated Assessment Framework in
Support of the Southern Appalachian Mountains Initiative, prepared for the Southern Appalachian
Mountains Initiative (SAMI), Asheville, NC, June 1998.
8. Federal Highway Planning Network version 2.1, U.S. Department of Transportation, Bureau of
Transportation Statistics, Federal Highway Administration, Washington, DC, 1998. (Web site
address: http://www.bts.gov/gis/ntatlas/networks.html)
9. Kinnee, E., C. D. Geron, T. Pierce, and T. Birth, Creation of a land use inventory for estimating
biogenic ozone precursor emission in the United States, submitted for publication in Ecological
Applications, 1995.
10. TIGER, U.S. Department of Commerce, Bureau of the Census, Washington, DC, 1998. (Web site
address: http://www.census.gov/geo/www/tiger/)
11. MABLE/Geocorr V2.5: The Geographic Correspondence Engine, U.S. Department of Commerce,
Bureau of the Census, Washington, DC, 1988. (Web site address: http://www.census.gov/plue/)
12. Gridded Population Data of the World, Consortium for International Earth Sciences Network, 1998.
(Web site address: http://www.ciesin.org/datasets/gpw/globaldem.doc.html)
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13. National Railway Network 1:100,000, U.S. Department of Transportation, Bureau of Transportation
Statistics, Federal Highway Administration, Washington, DC, 1998. (Web site address:
http: //w w w .bts .gov/gi s/ntatlas/networks .html)
14. Wilkinson, J. G., C. F. Loomis, D. E. McNally, R. A. Emigh, T. W. Tesche. Technical Formulation
Document: SARMAP/LMOS Emissions Modeling System (EMS-95), AG-90/TS26 and AG-90/TS27,
prepared for the Lake Michigan Air Directors Consortium, Des Plaines, IL and The Valley Air
Pollution Study Agency, Technical Support Division, Sacramento, CA, prepared by Alpine
Geophysics, Pittsburgh, PA, 1994.
15. Compilation of Air Pollutant Emission Factors, AP-42, Fifth Edition and Supplements, U.S.
Environmental Protection Agency, Research Triangle Park, NC, 1997.
16. Procedures for the Preparation of Emission Inventories for Carbon Monoxide and Precursors of
Ozone, Volume I, EPA-450/4-91-016, U.S. Environmental Protection Agency, Research Triangle
Park, NC, May 1991.
17. Procedures for Preparing Emissions Projections, EPA-450/4-91-019, U.S. Environmental
Protection Agency, Research Triangle Park, NC, July 1991.
18. Preferred and Alternative Methods for Estimating Air Emissions, Volume II, Point Sources
Preferred Methods, EHP, U.S. Environmental Protection Agency, Research Triangle Park, NC.
19. Preferred and Alternative Methods for Estimating Air Emissions, Volume HI, Area Sources
Preferred Methods, EIIP, U.S. Environmental Protection Agency, Research Triangle Park, NC.
20. Preferred and Alternative Method for Estimating Air Emissions, Volume IV, Mobile Sources,
Chapter 2, Use of Locality Specific Transportation Data for the Development of Mobile Source
Emission Inventories, EIIP, U.S. Environmental Protection Agency, Research Triangle Park, NC,
September 1996.
21. Procedures for Emission Inventory Preparation, Volume IV: Mobile Sources, EPA-450/4-81-016d
(Revised), U.S. Environmental Protection Agency, Research Triangle Park, NC, September 1992.
22. Preferred and Alternative Method for Estimating Air Emissions, Volume IV, Mobile Sources,
Chapter 3, Guidance for Estimating Lawn and Garden Activity Levels, EIIP, U.S. Environmental
Protection Agency, Research Triangle Park, NC, September 1997.
23. Preferred and Alternative Methods for Estimating Air Emissions, Volume V, Biogenic Sources
Preferred Methods, EIIP, U.S. Environmental Protection Agency, Research Triangle Park, NC,
May 1996.
24. Emission Methodology for Oil and Gas Seeps, California Air Resources Board, Sacramento, CA,
1993.
25. Guidance for the Preparation of Quality Assurance Plans for O3 /CO SIP Emission Inventories,
EPA-450/4-88-023, U.S. Environmental Protection Agency, Research Triangle Park, NC,
December 1988.
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26. Quality Assurance Program for Post-1987 Ozone and Carbon Monoxide State Implementation Plan
Inventories, EPA-450/4-89-004, U.S. Environmental Protection Agency, Research Triangle Park,
NC, March 1989.
27. Quality Review Guidelines for 1990 Base Year Inventories, EPA-450/4-91-022, U.S. Environmental
Protection Agency, Research Triangle Park, NC, September 1991.
28. Example Documentation Report for 1990 Base Year Ozone and Carbon Monoxide State
Implementation Plan Emission Inventories, EPA-450/4-92-007, U.S. Environmental Protection
Agency, Research Triangle Park, NC, March 1992.
29. Example Emissions Inventory Documentation for Post-1987 Ozone State Implementation Plans,
EPA-450/4-89-018, U.S. Environmental Protection Agency, Research Triangle Park, NC,
October 1989.
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APPENDIX A
DRAFT CONSOLIDATED EMISSIONS
REPORTING (CER) RULE
NOTE: THE ATTACHED DRAFT CER RULE IS BEING REVIEWED WITHIN EPA AND
MAY CHANGE. IT IS INCLUDED AS A DRAFT TO SHOW STATE AND LOCAL AGENCIES
WHAT EPA'S CURRENT INTENTIONS ARE. WHEN THE CER RULE BECOMES FINAL, IT
WILL TAKE PRECEDENCE OVER ALL APPLICABLE PORTIONS OF THIS GUIDANCE.
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 51
[AD-FRL- ]
RIN
Consolidated Emissions Reporting
AGENCY: Environmental Protection Agency (EPA)
ACTION: Proposed rule
SUMMARY: EPA is proposing this rule to improve and simplify emissions
reporting. Many state and local agencies asked EPA to take this action to:
determine reporting requirements; improve reporting efficiency; provide
flexibility for data gathering and reporting; better explain to program
managers and the public the need for a consistent inventory program.
Consolidated reporting should increase the efficiency of the emission
inventory program and provide more consistent and uniform data. Although EPA
is proposing the submission of more data for PM2-5, its precursors, and HAPs,
it is proposing to reduce the reporting requirements for other criteria
pollutants.
DATES: Submit comments on or before [insert date 45 days after date of
publication in the Federal Register].
ADDRESSES: Send comments (in duplicate, if possible) to: Air and Radiation
Docket (6102), US Environmental Protection agency, Attn: Docket No. A9840, 401
M Street, SW, Washington, DC 20460.
FOR FURTHER INFORMATION CONTACT: Steven Bromberg, Emissions, Monitoring, and
Analysis Division (MD-14), Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina,
27711, Telephone: (919) 541-1000, email:bromberg.steve@epamail.epa.gov.
SUPPLEMENTARY INFORMATION:
I. AUTHORITY
Sections 110(a) (2) (F) , 110 (a) (2) (K) , 110 (a) (2) (J) , 112, 182 (a) (3) (B) ,
172(c)(3), 182(a)(3)(A), 187(a)(5), 301(a)
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II. BACKGROUND
Emission inventories are critical for the efforts of state, local, and
federal agencies to attain and maintain the National Ambient Air Quality
Standards (NAAQS) that EPA has established for criteria pollutants such as
ozone, particulate matter, and carbon monoxide. Pursuant to its authority
under section 110 of Title I of the Clean Air Act, EPA has long required State
Implementation Plans (SIPs) to provide for the submission by States to EPA of
emission inventories containing information regarding the emissions of
criteria pollutants and their precursors (e.g., volatile organic compounds
(VOCs)). EPA codified these requirements in 40 CFR part 51, subpart Q in 1979
and amended them in 1987.
The 1990 Amendments to the Clean Air Act (Act) revised many of the
provisions of the Clean Air Act related to the attainment of the NAAQS and the
protection of visibility in mandatory class I Federal areas (certain national
parks and wilderness areas). These revisions establish new periodic inventory
requirements applicable to certain areas that were designated nonattainment
for certain pollutants. For example, section 182(a)(3)(A) required States to
submit an inventory every 3 years (3-Year cycle) for ozone nonattainment areas
beginning in 1993. Emissions reported must include VOC, NOX, and CO for
point, area, mobile (onroad and nonroad), and biogenic sources. Similarly,
section 187(a)(5) requires States to submit an inventory every 3 years for CO
nonattainment areas for the same source classes, except biogenic sources.
EPA, however, did not codify these statutory requirements in the CFR, but
simply relied on the statutory language to implement them.
EPA recently revised both the ozone and particulate matter NAAQS. EPA
established an 8-hour ozone standard that replaces the 1-hour ozone standard
applicable at the time of the 1990 Clean Air Act Amendments. EPA also revised
the PM10 standards and established new standards for PM2.5 and regional haze.
EPA also recently promulgated the NOX SIP Call (§51.122) which calls on 22
States and the District of Columbia to submit SIP revisions providing for NOX
reductions in order to reduce the amount of ozone and ozone precursors
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transported between states. As part of that rule, EPA established reporting
requirements to be included in the SIP revisions to be submitted by States in
accordance with that action.
This proposal consolidates the various reporting requirements that already
exist in one place in the CFR and establishes new ones for the PM2.5 NAAQS and
regional haze.
In this action, we refer to these types of inventories as the following:
• Point source inventories
• 3-Year cycle inventories
• NOX SIP call inventories
The Rule also takes advantage of data from Emission Statements available to
states but not reported to EPA. As appropriate, states may use this data to
meet their reporting requirements for point source data. Combining data from
these activities gets the most information from sources with the least burden
on the industry and less effort by state and local government agencies. By
treating this information as a comprehensive emission inventory, states and
local agencies may do the following:
• measure their progress in reducing emissions.
• have a tool they can use to support future trading programs.
• set a baseline from which to do future planning.
We intend these inventories to help nonattainment areas develop and meet
SIP requirements to reach the NAAQS. Inventories represent a typical work
week's daily emissions for peak nonattainment seasons, such as summer for 03
and winter for CO.
States use data obtained through current annual reporting requirements (in
the future to be called Point Source inventory) to record emissions from large
sources and to track progress in reducing emissions from them. States get 3-
Year cycle data from stationary sources with lower yearly emission levels and
use them with the point source inventories to update their emission inventory
every 3 years. States use this updated data to do the following:
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• measure trends in emission reductions
• demonstrate emission changes from previous years
• answer the public's request for information
As noted above, this proposal would require the submission of emissions
inventories to support the implementation of the new PM2.5 standards and
regional haze. States will need to inventory direct emissions of PM2.5 and its
precursors beginning in 2003 for the inventory year 2002. States will also
have to estimate direct emissions of soil dust and PM2 5 precursor emissions of
condensible organics and ammonia. These PM2 5 related data elements are needed
as input to emission models. The Administrator has determined that States
should submit statewide point and 3-Year cycle inventories for PM10, PM2.5, and
regional haze, consistent with the data requirements for 3-Year cycle
inventories for 03 and CO. Sections 110 (a) (2) (F) and 172 (c) provide ample
statutory for this proposal as it relates to criteria pollutants. Section
110(a)(2)(F) provides that SIPs are to require "as may be prescribed by the
Administrator... (ii)periodic reports on the nature and amounts of emissions
and emissions-related data from such sources." Section 172(c) (2) (3) provides
that SIPs for nonattainment areas are to "include a comprehensive, accurate,
current inventory of actual emissions from all sources of the relevant
pollutant or pollutants in such area, including such periodic revisions as the
Administrator may determine necessary to assure that the requirements of this
part are met." Additional statutory authority for emissions inventories from
1-hour ozone nonattainment areas is provided by section 182(a)(3)(A) and for
emissions inventories from CO nonattainment areas is provided by section
187(a)(5). Section 301(a) provides authority for EPA to promulgate
regulations embodying these provisions.
In addition to the emission inventory provisions related to NAAQS
pollutants, EPA is also proposing emission inventory provisions regarding
hazardous air pollutants (HAPs). EPA is proposing these provisions under
authority of section 301(a) which authorizes the Administrator to prescribe
such regulations as are necessary to carry out her functions under the Act.
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Title V of the Act requires the Administrator to perform an oversight role
with respect to State issued permits, including permits issued to major
sources of HAP emissions. In order to determine whether that program is being
appropriately and lawfully administrated by the States with respect to major
HAP sources, a HAP emission inventory is necessary. These regulations
requiring States to submit such an inventory to EPA are authorized by section
301{a).
States are developing programs to regulate Hazardous Air Pollutants (HAPs)
that are listed in section 112(b)(1) and their Title V programs must include
permits for all HAP sources emitting major quantities of HAPs (10 tons of one
HAP or 25 tons of multiple HAPs per year). Thus, the Administrator believes
including HAPs in the point source inventory is appropriate and necessary.
This information will help us support the HAP programs (MACT determinations,
support to residual risk, Urban Area source program, and the Great Waters
program).
What is the purpose of the Consolidated Emissions Reporting Rule (CERR)?
The purpose of this rule is threefold:
• simplify emissions reporting,
• offer options for data exchange, and
• unify reporting dates for various categories of inventories.
Previous requirements may have, at times, led to inefficient
reporting. This rule provides options for reporting that
allow States to match normal activities with federal
requirements.
This action consolidates the requirements of emission inventory programs
for point sources, 3-Year cycles, and NOX SIP Calls.
How are the CERR's requirements different from existing requirements?
(a) additional pollutants
Your State's inventory will add PM2.5, PM2.5 precursors, and HAPs to the
criteria pollutants.
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(b) geographic coverage of inventory
Your State now reports point source emissions statewide and emissions from
area and mobile sources by nonattainment area. Your State's new inventory
will be statewide by county for all source types, regardless of the attainment
status.
(c) frequency of reporting
Your State will continue to report emissions from very large point sources
(See Table 1) annually. Your State has a choice to report smaller point
sources every 3 years or one-third of the sources each year. Your State will
continue to report emissions from nonattainment areas for area and mobile
sources every 3 years. Attainment areas will be required, for the first time,
to report area and mobile source emissions.
How will EPA use the data collected under this reporting requirement?
EPA uses emission inventories to form realistic public policy by the
following:
• modeling analyses,
• projecting future control strategies,
• tracking progress to meet requirements of the Clean Air Act,
• calculating risk, and
• responding to public inquiries.
Why does EPA want xny State' s data?
Most of the information EPA needs are readily available from States
because of the State's efforts to follow the Clean Air Act and its amendments.
Using data States have already estimated or collected is a cheaper, more
efficient way for us to get information to analyze. EPA can pull your data
into a central repository of emissions data and extract what we need to
fulfill our mandates.
How will others use my data collected under this requirement?
Recent events have shown that some states need emissions data for areas
outside their borders. Programs such as the Ozone Transport Assessment Group,
the Ozone Transport Commission NOX Baseline study, and the Grand Canyon
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Visibility Transport Commission demonstrated this need. As we recognize
pollution as a regional problem, agencies will need multistate inventories
more often to do such things as regional modeling.
We can meet our common needs by creating a central repository of data from
state and local agencies, or a group of regional emissions data bases. Such
repositories offer the advantage of ready access and availability, common
procedures for ensuring the quality of data, and an ability to meet the
general needs of many potential users.
What happens if EPA doesn't get my agency's emissions data?
If we don't receive your emissions information at the time this rule
specifies, we'll use whatever we have to produce emissions data for your
agency. Congress often mandates our analyses, so we depend on you to complete
them. If we don't get your data, we must find other ways to compile similar
information.
We can estimate your agency's inventory by an of the following:
• national allocation (top down) methods,
• projecting from previous data, or
• using our best judgment.
For area and mobile sources, our methods usually represent your emissions
reasonably well. For point sources, our estimates are less accurate. We have
to estimate activity and plant parameters based on general knowledge rather
than using your specific information.
The Act provides for other actions against a State if we do not receive
your data. For example, if a State does not provide emissions data for NAAQS
pollutants, EPA may take actions such as making findings of failure to
implement, that are authorized in instances where a State fails to fulfill SIP
obligations. As the HAP emissions data would be required by this regulation,
States could face consequences under section 113 for failure to comply with a
regulation.
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III. ADMINISTRATIVE REQUIREMENTS
A. Executive Order 12866
Under Executive Order 12866 (58 FR 51735, October 4, 1993), we must
determine whether the regulatory action is "significant" and therefore subject
to review by the Office of Management and Budget (OMB) and to the Executive
Order's requirements. We've determined this action is "significant" and
therefore does require OMB review, based on the Order's definition of a
"significant" regulatory action as one that is likely to result in a rule that
may do any of the following:
1. Have an annual effect on the economy of $100 million or more or
materially harm the economy, a sector of the economy, productivity,
competition, jobs, the environment, public health or safety, or State and
local governments or communities. The ICR (EPA ICR No. 0916.09) analysis
shows that the costs to implement the Rule are less than $100 million.
2. Create a serious inconsistency or otherwise interfere with an action
taken or planned by another Agency. The rule will increase data consistency,
thus assisting other Agencies.
3. Materially alter the budgetary effect of entitlements, grants, user
fees, or loan programs or the rights and obligations of those who receive
them. Grant funds are being increased to State agencies.
4. Raise novel legal or policy issues arising out of legal mandates, the
President's priorities, or the principles in the Executive Order.
B. Paperwork Reduction Act
Today's action does require new information for newly regulated pollutants
but reduces reporting for previously regulated pollutants. It revises part 51
to consolidate old reporting requirements and recognizes new reporting needs
for PM2.5 and HAPs. The Office of Management and Budget has approved the
current information collection requirements in part 51 under the Paperwork
Reduction Act, 44 U.S.C. 3501 et seq. and has assigned OMB control number
2060-0088 (EPA ICR No. 916.07). A new information request (EPA ICR No.
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0916.09) that covers the new reporting requirements is being submitted to OMB
(OMB control number 2060-0088) for approval.
C. Impact on Small Entities
Under the Regulatory Flexibility Act we don't need to analyze this
proposed regulation's flexibility because it doesn't affect small entities
whose jurisdictions cover fewer than 50,000 people. Under 5 USC 605(b), I
certify that this action won't significantly affect the economic well-being of
a substantial number of small entities. Also, because this modification is
minor, it requires no additional review.
D. E.O. 13045: Children's Health Protection
Executive Order 13045: "Protection of Children from Environmental health Risks
and Safety Risks" (62FR19885, April 23, 1997) applies to any rule that: (1) is
determined to be "economically significant" as defined under E.O. 12866, and
(2) concerns an environmental health or safety risk that EPA has reason to
believe may have a disproportionate effect on children. If the regulatory
action meets both criteria, the Agency must evaluate the environmental health
or safety effects of the planned rule on children, and explain why the planned
regulation is preferable to other potentially effective and reasonably
feasible alternatives considered by the Agency.
EPA interprets E.O. 13045 as applying only to those regulatory actions
that are based on health or safety risks, such that the analysis required
under section 5-501 of the Order has the potential to influence the
regulation. This rule is not subject to E.O. 13045 because it is based on
technology performance and not on health or safety risks.
E. The National Technology Transfer and Advancement Act
Section 12(d) of the National Technology Transfer and Advancement Act of
1995 (NTTAA), Pub L. No. 104-113, § 12(d) (15 U.S.C. 272 note) directs EPA to
use voluntary consensus standards in its regulatory activities unless to do so
would be inconsistent with applicable law or otherwise impractical. Voluntary
consensus standards are technical standards (e.g., materials specifications,
test methods, sampling procedures, and business practices) that are developed
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or adopted by voluntary consensus standards bodies. The NTTAA directs EPA to
provide Congress, through OMB, explanations when the Agency decides not to use
available and applicable voluntary consensus standards.
This proposed rule making does not involve technical standards. Therefore,
EPA is not considering the use of any voluntary consensus standards.
F. Unfunded Mandates Reform Act
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), P.L. 104-4,
establishes requirements for Federal agencies to assess the effects of their
regulatory actions on State, local, and tribal governments and the private
sector. Under section 202 of the UMRA, EPA generally must prepare a written
statement, including a cost-benefit analysis, for proposed and final rules
with "Federal mandates" that may result in expenditures to State, local, and
tribal governments, in the aggregate, or to the private sector, of $100
million or more in any one year. Before promulgating an EPA rule for which a
written statement is needed, section 205 of the UMRA generally retires EPA to
identify and consider a reasonable number of regulatory alternatives and adopt
the least costly, most cost-effective or least burdensome alternative that
achieves the objectives of the rule. The provisions of section 205 do not
apply when they are inconsistent with applicable law. Moreover, section 205
allows EPA to adopt an alternative other than the least costly, most cost-
effective or least burdensome alternative if the Administrator publishes with
the final rule an explanation why that alternative was not adopted. Before
EPA establishes any regulatory requirements that may significantly or uniquely
affect small governments, including tribal governments, it must have developed
under section 203 of the UMRA a small government agency plan. The plan must
provide for notifying potentially affected small governments, enabling
officials of affected small governments to have meaningful and timely input in
the development of EPA regulatory proposals with significant Federal
intergovernmental mandates, and informing, educating, and advising small
governments on compliance with the regulatory requirements.
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EPA has determined that this rule does not contain a Federal mandate that
may result in expenditures of $100 million or more for State, local, and
tribal governments, in the aggregate, or the private sector in any one year.
The additional work required by this rule takes advantage of information
already in the possession of reporting groups. Using existing data leverages
past work and reduces the burden of this rule. This conclusion is supported by
the analysis done in support of EPA ICR No. 0916.09, OMB control number 2060-
0088. Thus, today's rule is not subject to the requirements of sections 202
and 205 of the UMRA.
G. Executive Order 12875: Enhancing the Intergovernmental Partnership
Under Executive Order 12875, EPA may not issue a regulation that is not
required by statute and that creates a mandate upon a State, local or tribal
government, unless the Federal government provides the funds necessary to pay
the direct compliance costs incurred by those governments, or EPA consults
with those governments. If EPA complies by consulting, Executive Order 12875
requires EPA to provide to the Office of Management and Budget a description
of the extent of EPA's prior consultation with representatives of affected
State, local and tribal governments, the nature of their concerns, copies of
any written communications from the governments, and a statement supporting
the need to issue the regulation. In addition, Executive Order 12875 requires
EPA to develop an effective process permitting elected officials and other
representatives of State, local and tribal governments to provide meaningful
and timely input in the development of regulatory proposals containing
significant unfunded mandates.
Today's rule does not create a mandate on State, local, or tribal
governments. As explained in the discussion on UMRA (Section III.D), this
rule does not impose an enforceable duty on these entities. Accordingly, the
requirements of section 1(a) of Executive Order 12875 do not apply to this
rule.
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H. Executive Order 13084: Consultation and Coordination with Indian Tribal
Governments
Under Executive Order 13084, EPA may not issue a regulation that is not
required by statute, that significantly or uniquely affects the communities of
Indian tribal governments, and that imposes substantial direct compliance
costs on those communities, unless the Federal government provides the funds
necessary to pay the direct compliance costs incurred by the tribal
governments, or EPA consults with those governments. IE EPA complies by
consulting, Executive Order 13084 requires EPA to provide to the Office of
Management and Budget, in a separately identified section of the preamble to
the rule, a description of the extent of EPA's prior consultation with
representatives of affected tribal governments, a summary of the nature of
their concerns, and a statement supporting the need to issue the regulation.
In addition, Executive Order 13084 requires EPA to develop an effective
process permitting elected officials and other representatives of Indian
tribal governments to provide meaningful and timely input in the development
of regulatory policies on matters that significantly or uniquely affect their
communities.
Today's rule does not significantly or uniquely affect the communities
of Indian tribal governments. Accordingly, the requirements of section 3(b)
of Executive Order 13084 do not apply to this rule.
CONSOLIDATED EMISSIONS REPORTING. PAGE 13 OF 38
List of Sublects in 40 CFR Part 51
Environmental protection, Administrative practice and procedure, Air pollution
control, Intergovernmental relations, Reporting and record keeping
requirements.
Dated: Carol M. Browner,
Administrator.
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For the reasons stated in the preamble, title 40, chapter I, of the Code
of Federal Regulations is proposed to be amended as follows:
PART 51 — [AMENDED]
1. The authority citation for part 51 continues to read as follows:
Authority: 42 U.S.C. 7401-7671q.
2. Part 51 is amended by adding subpart A to read as follows:
Subpart A - Emission Inventory Reporting Requirements
Sec.
51.001 For what sources must States do emissions reporting?
GENERAL INFORMATION FOR INVENTORY PREPARERS
51.005 Who is responsible for actions described in this rule?
51.010 What tools are available to help prepare and report
emissions data?
51.015 How does my State reduce the effort for reporting?
SPECIFIC REPORTING REQUIREMENTS
51.020 What data does my State need to report to EPA?
51.025 What are the emission thresholds that separate point and area
sources?
51.030 What geographic area must my State's inventory cover?
51.035 When does my State report the data to EPA?
51.040 In what form should my State report the data to EPA?
51.045 Where should my State report the data?
Appendix A to Subpart A of Part 51 - Tables and Glossary
§51.001 For what sources must States do emissions reporting?
(a) Point sources for which States must report emissions annually under
§51.321 are defined as follows:
(1) For PM10, PM2.5, ammonia, sulfur oxides, VOC, and nitrogen
oxides, any plant that actually emits at least 90.7 metric tons (100 tons) per
year of any pollutant.
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(2) For carbon monoxide, any plant that actually emits at least
907 metric tons (1000 tons) per year.
(3) For lead and lead compounds measured as elemental lead, any
plant that actually emits at least 4.5 metric tons (5 tons) per year.
(4) For HAPs, any plant that actually emits at least 10 tons per
year of any HAP or at least 25 tons per year of two or more HAPs combined.
(b) Annual reporting applies only to an emission point within the
plant that emits:
(1) For PM10, PM2 5, ammonia, sulfur oxides, VOC and nitrogen
oxides, at least 22.7 metric tons (25 tons) per year.
(2) For carbon monoxide, at least 227 metric tons (250 tons) per
year.
(3) For lead or lead compounds measured as elemental lead, at
least 4.5 metric tons (5 tons) per year.
(4) For HAPs, at least 10 tons per year of one HAP or 25 tons per
year of two or more HAPs.
GENERAL INFORMATION FOR INVENTORY PREPARERS
§51.005 Who is responsible for actions described in this rule?
State and local agencies whose geographic coverage include any point,
area, mobile, or biogenic sources must inventory these sources and report this
information to EPA.
§51.010 What tools are available to help prepare and report emissions data?
(a) We urge your State to use estimation procedures described in
documents from the Emission Inventory Improvement Program (EIIP). Their
procedures are standardized and ranked according to relative uncertainty for
each emission estimating technique. Using this guidance will enable others to
use your State's data and be able to evaluate its quality and consistency with
other data. If your State chooses not to use the EIIP estimating methods,
your State should follow the procedures EIIP recommends for assigning
appropriate uncertainty scores to your emission estimates.
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(b) Your State should use traditional estimating procedures for HAPs
(emission factor x activity level) as the EIIP documents describe. However,
if your State has developed a speciation profile unique to a local source, you
may use it instead of the traditional approach to estimate emissions.
§51.015 How does my State reduce the effort for reporting?
(a) Compiling smaller point source (Type B) and 3-Year cycle inventories
means much more effort every 3 years, but your state may ease this workload
spike by reporting one-third of your Type B point and 3-Year cycle sources
each year. For these sources, your State will therefore have data from 3
successive years at any given time, rather than from the single year in which
it is compiled. If your State needs to inventory the entire category of Type
B point and 3-Year cycle sources in a single year, your State should report
this data instead of a third of the estimates each year. If your State is a
NOX SIP Call state as defined in §51.122, your State can't use these optional
reporting frequencies for NOX.
(b) If your State needs a base year emission inventory for a selected
pollutant, your State must compile an inventory of all affected source
categories for the specified year.
(c) If your State choose the method of reporting one-third of your Type
B sources and 3-Year cycle sources each year, your State must compile each
year of the 3 year period identically. For example, if a process hasn't
changed for a source category or individual plant, your State must use the
same emission factors to calculate emissions for each year of the 3 year
period. If your State has revised emission factors during the 3 years for a
process that hasn't changed, resubmit previous year's data using the revised
factor. If your State uses models to estimate emissions during any year of
the 3 year period, make them identical for all 3 years.
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SPECIFIC REPORTING REQUIREMENTS
§51.020 What data does my State need to report to EPA?
(a) Pollutants. (1) Report emissions of the following:
(I) Sulfur oxides.
(ii) VOC.
(iii) Nitrogen oxides.
(iv) Carbon monoxide.
(v) Lead and lead compounds.
(vi) Particulate matter.
(vii) PM10.
(viii) PM2.5.
(ix) PM2 5 precursors.
(x) HAPs.
(2) See Table 3 of appendix A to this subpart for the HAPs covered under
this rule. Table 4 of appendix A to this subpart contains the priority list
of HAPs to be inventoried. If your State has inventory data for any of the
remaining HAPs listed in Table 3 of appendix A to this subpart, we encourage
you to submit this information along with the data on Table 4 of appendix A to
this subpart HAPs. If your State can show that a HAP has a residual risk of
less that one in a million, it does not have to report that pollutant.
(b) Supporting information. Report the data elements in Table 2a through
2d of appendix A to this subpart. Depending on the format you choose to
report your State data, additional information not listed in Tables 2a through
2d will be required. Specific instructions for your State system format
should be consulted. Any you don't report we'll have to generate with our own
techniques. We may ask you for other data to meet special requirements.
(c) Confidential data. We don't consider the data in Tables 2a through
2d of appendix A to this subpart confidential, but some states limit release
of this type of data. If Federal and State requirements are inconsistent,
consult your EPA Regional Office for a final reconciliation.
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§51.025 What are the emission thresholds that separate point and area
sources?
(a)(l) Use the following actual emissions thresholds in attainment areas
for point source reporting:
(I) At least 100 tpy for SOX, VOC, NOX, PM10, PM2.S.
(ii) At least 1000 tpy for CO.
(iii) At least 5 tpy for Pb.
(iv) At least 10 tpy for HAPs.
(2) See Table 1 of appendix A to this subpart for reporting thresholds
on point sources in nonattainment areas.
(b) Your State has the option to inventory and report any stationary
sources below these thresholds as point or area sources. If you have lower
emission thresholds for point sources in your state, you should use them. See
Table 1 of appendix A to this subpart for thresholds to report 3-Year cycle
data and Tables 2a through 2d of appendix A to this subpart for data elements
to report.
(c) In moderate PM10 nonattainment areas your State should inventory
sources emitting at least 100 tpy (actual) as point sources. In serious PM10
nonattainment areas, this requirement applies to sources emitting at least 70
tpy (actual). Inventory PM2.5 sources emitting at least 100 tpy (actual) as
point sources. Inventory ammonia (a precursor to PM2.5) as a point or area
source. We recognize that some HAPs in Table 3 of appendix A of this subpart
may be precursors to PM2.5, so, your State may inventory them as point or area
sources, as appropriate.
(d) A HAP point source is any stationary facility emitting at least 10
tpy (actual) of any individual HAP, or at least 25 tpy for any combination of
HAPs. Your State has the option to inventory and report facilities emitting
less than these thresholds as point or area sources. If your State has lower
emission thresholds for point sources, you should use them.
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(e) Reexamine the list of HAP facilities each year of the cycle. Work
with your EPA Regional Office periodically to examine the HAP sources being
inventoried and insure they're relevant.
§51.030 What geographic area must my State's inventory cover?
Because of the regional nature of these pollutants, your State's
inventory must be statewide, regardless of an area's attainment status.
§51.035 When does my State report the data to EPA?
Your State must report data for all inventory types 12 months (by
December 31) after the end of the calendar year.
(a) Point source.(1) As seen in Table 1 of appendix A to this subpart,
your State should divide your point source inventory into two subsets - Type A
source inventory and Type B source inventory - with different reporting
frequencies. Report actual annual emissions from Type A point sources each
calendar year. Review stack data (height, diameter, flow rate, temperature,
velocity, and stack number) every 3 years and send in changes shown in Table
2a of appendix A to this subpart.
(2) For point sources within your state that your State is controlling
to meet the NOX reductions in § 51.121, submit estimates of NOX annually for
the ozone season.
(b) 3-Year cycle. (1) Your State should send EPA its annual and daily
estimates of actual emissions every 3 years for Type B point sources and area
and mobile sources. For Type B point source inventories, include facilities
not reported under the Type A source requirement. Area data includes sources
below the thresholds for Type B point sources. Report HAPs on the same
frequency as the Type B inventories. Your State may report emissions from
one-third of your State's Type B, area, and mobile sources each year or from
all sources every 3 years.
(2) Your State and your EPA Regional Office may tailor the reporting by
selecting sources that most affect your agency.
(3) We encourage your State to integrate your State's own reporting
requirements with EPA's. If your State legislature requires HAP data
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reporting, contact your EPA Regional Office to reconcile your state and
federal reporting requirements.
(4) If sources within your state are controlled to meet NOX reductions
in §51.121, your State must report all their NOX area and mobile source data
every year.
(c) Other. Your State must establish an initial baseline for biogenic
emissions. Your State need not submit more biogenic data unless land use
characteristics or the methods for estimating emissions change. If either of
these variables change, your State must report new biogenic emissions during
the reporting period in the following year as shown in Table 2d of appendix A
of this subpart.
§51.040 In what form should icy State report the data to EPA?
(a) For better access by everyone, report emissions in your State in an
electronic format using one of the following options:
(1) Submit your State's data in the EIIP/NET Input format.
(2) Submit your State's data in the AIRS-AFS format.
(3) Submit your State's data in the EIIP/EDI format.
(b) Some meta data describing your submission are-not listed in Tables
2a through 2d of appendix A of this subpart are also required. Because
electronic reporting technology continually changes, contact your EPA Regional
Office for acceptable formats. You should consult specific instructions for
your State system format to determine additional requirements not listed in
Tables 2a through 2d. You can find specific instructions for each optional
format at the following Internet addresses:
(1) EIIP/NET Input format -
www.epa.gov/oar/oaqps/efig/ei/index.html#Data
(2) AIRS-AFS format - www.epa.gov/ttnairsl/afs/
(3) EIIP/EDI format -
www.epa.gov/ttn/chief/eiip/techrep.htm#dmproc
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§51.045 Where should my State report the data?
(a) Your State may continue entering your data to the EPA AIRS system
using the AFS format for point sources.
(b) If your State uses either the EIIP/NET Input format the EIIP/EDI
format, you State submits or reports data by either providing it to another
party directly or notifying the other party that it is available in the
specified format and at a specific electronic location (FTP site). For an
individual plant your State may continue to report data directly to us under
40 CFR part 96 or Subpart H of 40 CFR Part 75.
(c) For the latest information on data reporting procedures, call our
Info Chief help desk at (919)541-5285 or email to info.chief@epamail.epa.gov.
Appendix A to Subpart A of Part 51 - Tables and Glossary
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Table 1. Summary of Requirements For Reporting Emission Inventories
Provision Point Source Invento
Type A Type B
Sources1 Sources1
ry NO, SIP Call 3-Year Inventory
Inventory
CAA § 110(a) (2) (F) §110(a) (2) (F) , §110(a)(2) §172(c)(3).
citation § 112
Frequency Annual Every 3
of
reporting
§ 182(a) (3) (A) ,and
§ 187(a) (5) , § 112
years Annual Every 3 years
Estimating Annual Annual and Five month Annual and Daily4
period Daily4
season
Areas to Entire U.S. Entire U.S. NOX SIP Call Entire U.S.
which (Statewide) (Statewide) areas (Statewide)
provision
applies
(Statewide)
Pollutants Pollutant Pollutant Pollutant Pollutant
and source tpy2
size SOX2 2,500 SOX2
thresholds NOX;> 2,500 NOX2
VOC2 250 VOC2
tpy
100 tpv Ozone NA areas5:
100 NOX ;> 100 tpy
100 VOCi 10
PM10 ;> 250 PM102 100 Lesser NOX2 100
PM2.52 250 PM2.5s 100 thresholds C02 100
CO a 2, 500 CO s 1
Pb i
3HAPS2
, 000 to be
5 defined by CO NA areas5:
10 state. COs 100
All sources PM-10 NA areas5:
not PM10a 70 (serious)
inventoried PM10s 100 (moderate)
as point
sources PM, ^ NA areas5:
shall be PM2.52 100
inventoried
as area or Ammonia may be
mobile inventoried as a
sources and point or area source
reported
only if Inventory includes:
they are to • Point sources ;>
be specified tpy.
controlled • Area sources <
to meet specified tpy.
emission • Onroad mobile
budget . sources .
• Nonroad mobile
sources .
• Biogenic sources .
1 Previously, the Type A sources and the Type B sources together constituted the annual inventory
(40 CFR Part 51.321-323); all such sources were required to report annually.
2 tpy = tons per year.
3 A HAPs point source is defined as a stationary source emitting 10 tpy or more of any individual
HAP, or 25 tpy or more of any combination of HAPs. Facilities emitting less than these threshold
amounts will be inventoried and reported as area sources unless already inventoried as a point
source.
4 Ozone daily emissions = summer work weekday; CO daily emissions = winter work weekday; PM daily
emissions = to be defined in consultation with Regional office.
5 Thresholds apply to nonattainment areas only; remainder of state uses Type B Source thresholds
to distinguish between point and area sources.
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Table 2a. Data Elements that States Must Report for Point Sources
Data Elements Annual
Entire NOX SIP
US Call
Emission levels VOC2250 Nox2ioo
NOX;>2500
SOX22500 Lesser
PM102250 thresholds
PM2 52250 to be
CO defined by
22500 state
Inventory year •
Inventory start date •
Inventory end date •
Inventory type •
State FIPS code • •
County FIPS code • •
Federal ID code • •
(plant)
Federal ID code • •
(point)
Federal ID code • •
(process)
Site name • •
Physical address • •
sec • •
Heat content • •
( fuel) (annual)
Ash content • •
(fuel ) (annual )
Sulfur content • •
(fuel) (annual )
Heat content •
(fuel) (seasonal)
Source of fuel heat •
content
Pollutant code • •
Activity/throughput • •
(annual)
Activity/throughput • •
(daily)2
Activity/throughput •
(NOX ozone season)
Source of •
activity /throughput
(NOX ozone season)
Work weekday emissions • •
Every 3 Years
Entire NAA NOX SIP
US Call
VOC2100 tyOCilO NOX2100
NOx2lOO 'NC^z 100
SOX2100 1PM10*70
PM102lOO 'CO 2100
PM2 52lOO
CO 21000
Pb 25
3HAPS2lO
NH3
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• •
• •
•
•
• • •
• • •
• •
•
•
• • •
A-24
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Data Elements Annual
Entire NOX SIP
US Call
Annual emissions • •
NOX Ozone season •
emissions
Area classification •
Emission factor • •
Source of emission •
factor ,
Winter throughput (%) •
Spring throughput (%) •
Summer throughput (%) •
Fall throughput (%) •
Hr/day in operation • •
Start time (hour) • •
Day/wk in operation • •
Wk/yr in operation • •
Federal ID code (stack
number)
X stack coordinate
(latitude)
Y stack coordinate
(longitude)
Stack Height
Stack diameter
Exit gas temperature
Exit gas velocity
Exit gas flow rate
SIC/NAICS
Design capacity
Maximum nameplate
capacity
Primary control eff (%)
Secondary ctl eff (%)
Control device type
Rule effectiveness (%)
Every 3 Years
Entire NAA NOX SIP
US Call
• •
•
•
• • •
•
• •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• • •
• •
1 Both daily and annual emission estimates required
2 May be derived from annual or seasonal throughput.
3 Any stationary facility emitting 10 tpy or more of any individual HAP, or 25 tpy or more of any
combination of HAPs.
A-25
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Table 2b. Data Elements that States Must Report for Area and
Nonroad Sources
Data Elements Annual
Entire NOX
US SIP
Call
Emissions levels
Inventory year
Inventory start
date
Inventory end date
Inventory type
State PIPS code
County FIPS code
sec
Emission factor
Source of emission
factor
Activity /throughput
level (annual)
Activity /throughput
(daily)2
Activity /throughput
(NOX ozone season)
Source of
activity /throughput
(NOX ozone season)
Total
capture /control
efficiency (%)
Rule effectiveness
(%)
Rule penetration
(%)
Pollutant code
Summer /winter work
weekday emissions
Annual emissions
NOX Ozone season
emissions
Every 3 Years
Entire NAA NOX SIP
US Call
'voc
-------
Data Elements
Source of emissions
data
Winter throughput
(%)
Spring throughput
(%)
Summer throughput
(%)
Fall throughput {%)
Hr/day in
operations
Day/wk in
operations
Wk/yr in operations
Annual
Entire NOX
US SIP
Call
Every 3 Years
Entire NAA NOX SIP
US Call
•
•
• •
• •
• •
• •
• •
• •
1 Both daily and annual emission estimates required
2 May be derived from annual or seasonal throughput.
A-27
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Table 2c. Data Elements that States Must Report for Onroad Mobile Sources
Data Elements Annual
Entire NOX
US SIP
Call
Inventory year
Inventory start
date
Inventory end date
Inventory type
State FIPS code
County FIPS code
sec
Emission factor1
Activity (VMT by
Roadway Class)
Source of activity
data
Pollutant code
Summer /winter work
weekday emissions
Annual emissions
NOX ozone season
emissions
Source of emissions
data
Every 3 Years
Entire NAA NOX SIP
US Call
• •
• •
• •
• •
• •
• •
• •
• •
• •
•
• •
• •
•
•
•
1 Mobile model input files should be submitted
A-28
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Table 2d. Data Elements that States Must Report for Biogenic Sources
Data Elements
Inventory year
Inventory start
date
Inventory end date
Inventory type
State FIPS code
County FIPS code
sec
Pollutant code
Summer/winter work
weekday emissions
Annual emissions
Annual
Entire NOX
US SIP
Call
Every 3 Years
Entire NAA NOX SIP
US Call
•
"
•
•
•
•
•
•
"
•
A-29
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Table 3. Hazardous Air Pollutants (HAPs)
Chemical Abstracts
Service Pollutant
Number
Chemical Abstracts
Service Pollutant
Number
75-07-0 Acetaldehyde
60-35-5 Acetamide
75-05-8 Acetonitrile
98-86-2 Acetophenone
53-96-3 2-Acetylaminofluorene
107-02-8 Acrolein
79-06-1 Acrylamide
79-10-7 Acrylic acid
107-13-1 Acrylonitrile
107-05-1 Allyl chloride
92-67-1 4-Aminobiphenyl
62-53-3 Aniline
90-04-0 o-Anisidine
1332-21-4 Asbestos
71-43-2 Benzene (including
benzene from gasoline)
92-87-5 Benzidine
98-07-7 Benzotrichloride
100-44-7 Benzyl chloride
92-52-4 Biphenyl
117-81-7 Bis(2ethylhexyl)
phthalate (DEHP)
542-88-1 Bis(chloromethyl) ether
75-25-2 Bromoform
106-99-0 1,3-Butadiene
156-62-7 Calcium cyanamide
105-60-2 Caprolactam
(Removed 6/18/96,
61FR30816)
133-06-2 Captan
63-25-2 Carbaryl
75-15-0 Carbon disulfide
56-23-5 Carbon tetrachloride
463-58-1 Carbonyl sulfide
120-80-9 Catechol
133-90-4 Chloramben
57-74-9 Chlordane
7782-50-5 Chlorine
79-11-8 Chloroacetic acid
532-27-4 2-Chloroacetophenone
108-90-7 Chlorobenzene
510-15-6 Chlorobenzilate
67-66-3 Chloroform
107-30-2 Chloromethyl methyl
ether
126-99-8 Chloroprene
1319-77-3 Cresol/Cresylic acid
(mixed isomers)
95-48-7 o-Cresol
108-39-4 m-Cresol
106-44-5 p-Cresol
98-82-8 Cumene
N/A 2,4-D
(2,4-Dichloro-
phenoxyacetic Acid)
(including salts and
esters)
72-55-9 DDE (1,l-dichloro-2,2-
bis(p-chlorophenyl)
ethylene)
334-88-3 Diazomethane
132-64-9 Dibenzofuran
96-12-8 l,2-Dibromo-3-
chloropropane
84-74-2 Dibutyl phthalate
106-46-7 1,4-Dichlorobenzene
91-94-1 3,3'-Dichlorobenzidine
111-44-4 Dichloroethyl ether
(Bis[2-
chloroethyl]ether)
542-75-6 1,3-Dichloropropene
62-73-7 Dichlorvos
111-42-2 Diethanolamine
64-67-5 Diethyl sulfate
119-90-4 3,3'-Dimethoxybenzidine
60-11-7 4-Dimethylaminoazo
benzene
121-69-7 N,N-Dimethylaniline
119-93-7 3,3'-Dimethylbenzidine
79-44-7 Dimethylcarbamoyl
chloride
68-12-2 N,N-Dimethylformamide
57-14-7 1,1-Dimethylhydrazine
131-11-3 Dimethyl phthalate
77-78-1 Dimethyl sulfate
N/A 4,6-Dinitro-o-cresol
(including salts)
51-28-5 2,4-Dinitrophenol
121-14-2 2,4-Dinitrotoluene
123-91-1 1,4-Dioxane
(1,4-Diethyleneoxide)
122-66-7 1,2-Diphenylhydrazine
106-89-8 Epichlorohydrin
(l-Chloro-2,3-
epoxypropane)
106-88-7 1,2-Epoxybutane
140-88-5 Ethyl acrylate
100-41-4 Ethylbenzene
51-79-6 Ethyl carbamate
(Urethane)
75-00-3 Ethyl chloride
(Chloroethane)
106-93-4 Ethylene dibromide
(Dibromoethane)
107-06-2 Ethylene dichloride
(1,2-Dichloroethane)
107-21-1 Ethylene glycol
A-30
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151-56-4 Ethyleneimine 684-93-5
(Aziridine) 62-75-9
75-21-8 Ethylene oxide 59-89-2
96-45-7 Ethylene thiourea 56-38-2
75-34-3 Ethylidene dichloride 82-68-8
(1,1-Dichloroethane)
50-00-0 Formaldehyde 87-86-5
76-44-8 Heptachlor 108-95-2
118-74-1 Hexachlorobenzene 106-50-3
87-68-3 Hexachlorobutadiene 75-44-5
N/A 1,2,3,4,5,6- 7803-51-2
Hexachlorocyclyhexane N/A
(all stereo isomers, 85-44-9
including lindane) 1336-36-3
77-47-4 Hexachlorocyclo-
pentadiene
67-72-1 Hexachloroethane 1120-71-4
822-06-0 Hexamethylene 57-57-8
diisocyanate 123-38-6
680-31-9 Hexamethyl-phosphoramide 114-26-1
110-54-3 Hexane
302-01-2 Hydrazine 78-87-5
7647-01-0 Hydrochloric acid
(Hydrogen chloride [gas 75-56-9
only]) 75-55-8
7664-39-3 Hydrogen fluoride
(Hydrofluoric acid) 91-22-5
123-31-9 Hydroquinone 106-51-4
78-59-1 Isophorone
108-31-6 Maleic anhydride 100-42-5
67-56-1 Methanol 96-09-3
72-43-5 Methoxychlor 1746-01-6
74-83-9 Methyl bromide
(Bromomethane) 79-34-5
74-87-3 Methyl chloride
(Chloromethane) 127-18-4
71-55-6 Methyl chloroform
(1,1,1-Trichloroe-thane) 7550-45-0
78-93-3 Methyl ethyl ketone 108-88-3
(2-Butanone) 95-80-7
60-34-4 Methylhydrazine 584-84-9
74-88-4 Methyl iodide 95-53-4
(lodomethane) 8001-35-2
108-10-1 Methyl isobutyl
ketone(Hexone) 120-82-1
624-83-9 Methyl isocyanate 79-00-5
80-62-6 Methyl methacrylate 79-01-6
1634-04-4 Methyl tert-butyl ether 95-95-4
101-14-4 4,4'-Methylenebis(2- 88-06-2
chloroaniline) 121-44-8
75-09-2 Methylene chloride 1582-09-8
(Dichloromethane) 540-84-1
101-68-8 4,4'-Methylenedi-phenyl 108-05-4
diisocyanate 593-60-2
(MDI) 75-01-4
101-77-9 4,4'-Methylene-dianiline 75-35-4
91-20-3 Naphthalene
98-95-3 Nitrobenzene 1330-20-7
92-93-3 4-Nitrobiphenyl
100-02-7 4-Nitrophenol 95-47-6
79-46-9 2-Nitropropane 108-38-3
N-Nitroso-N-methylurea
N-Nitrosodime-thylamine
N-Nitrosomorpholine
Parathion
Pentachloroni-trobenzene
(Quintobenzene)
Pentachlorophenol
Phenol
p-Pheny1enedi amine
Phosgene
Phosphine
Phosphorus Compounds
Phthalic anhydride
Polychlorinated
biphenyls
(Aroclors)
1,3-Propane sultone
beta-Propiolactone
Propionaldehyde
Propoxur
(Baygon)
Propylene dichloride
(1,2-Dichloropropane)
Propylene oxide
1,2-Propylenimine
(2-Methylaziridine)
Quinoline
Quinone
(p-Benzoquinone)
Styrene
Styrene oxide
2,3,7,8-Tetrachloro-
dibenzo-p-dioxin
1,1,2,2-Tetrachloroe-
thane
Tetrachloroethylene
(Perchloroethylene)
Titanium tetrachloride
Toluene
Toluene-2,4-diamine
2,4-Toluene diisocyanate
o-Toluidine
Toxaphene
(chlorinated camphene)
1,2,4-Trichloro-benzene
1,1,2-Trichloroethane
Trichloroethylene
2,4,5-Trichlorophenol
2,4,6-Trichlorophenol
Triethylamine
Trifluralin
2,2,4-Trimethyl-pentane
Vinyl acetate
Vinyl bromide
Vinyl chloride
Vinylidene chloride
(1,1-Dichloroethylene)
Xylenes
(mixed isomers)
o-Xylene
m-Xylene
A-31
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106-42-3 p-Xylene
Antimony Compounds
Arsenic Compounds
(inorganic including
arsine)
Beryllium Compounds
Cadmium Compounds
Chromium Compounds
Cobalt Compounds
Coke Oven Emissions
Cyanide Compounds1
Glycol ethers2
Lead Compounds
Manganese Compounds
Mercury Compounds
Fine mineral fibers3
Nickel Compounds
Polycyclic Organic
Matter4
Radionuclides (including
radon)5
Selenium Compounds
NOTE: Unless otherwise specified, all listings above which contain the word
compounds or glycol ethers include any unique chemical substance that contains
the named chemical (i.e., antimony, arsenic, etc.) as part of that chemical's
infrastructure.
1. X'CN where X = H' or any other group where a formal dissociation may
occur. For example, KCN or Ca(CN)2.
2. (Under review) Glycol Ether draft ptions for defining:
Possible Correction to CAA 112(b)(1) footnote that would be consistent with
OPPTS modified definition.
New OPPTS definition as published is:
R - (OCH2CH2)n - OR' where:
n = 1,2, or 3
R = alkyl C7 or less
or R = phenyl or alkyl substituted phenyl
R' = H or alkyl C7 or less
or OR'= carboxylic acid ester, sulfate, phosphate, nitrate or
sulfonate
CAA's definition of Glycol ether exactly as in the statute (errors included):
"Includes mono- and di ethers of ethylene glycol, diethylene glycol, and
triethylene glycol
R - (OCH2CH2)n-OR' where n = 1,2, or 3
R = alkyl or aryl groups
R' = R,H or groups which, when removed, yield glycol ethers with
the structure R-(OCH2CH)n-OH. Polymers are excluded from the
glycol category.
CAA's definition of Glycol ether with technical correction, (a 2 was left out
of the last formula)
A-32
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"Includes mono- and di- ethers of ethylene glycol, diethylene glycol, and
triethylene glycol R-(OCH2CH2)n -OR' where
n = 1, 2, or 3
R = alkyl or aryl groups
R' = R, H, or groups which, when removed, yield glycol ethers with
the structure: R-(OCH2CH2)n-OH. Polymers are excluded from the
glycol category.
3- (Under Review)
4- (Under Review)
5- A type of atom which spontaneously undergoes radioactive decay.
Table 4. Priority Hazardous Air Pollutants (HAPS)
HAP
Acetaldehyde
Acrolein
Acrylamide
Acrylonitrile
Arsenic & compounds
Benzene
Benzyl chloride
Beryllium & compounds
bis(2-ethylhexyl)phthalate
1,3-Butadiene
Cadmium & compounds
Carbon tetrachloride
Chlorine
Chloroform
Chromium & compounds
Coke oven emissions
1,2-Dibromoethane
1, 2-Dichloroethane
1, 4-Dichlorobenzene
1, 2-Dichloropropane
1, 3-Dichloropropene
1, 4-Dioxane
Ethyl acrylate
Ethylene dichloride
Ethylene oxide
Ethylidene dichloride
Forma1dehyde
Glycol ethers
Hexachlorobenzene
Hexachlorocyclopentadiene
Hydrazine
Hydrochloric acid
Lead & compounds
Maleic anhydride
Manganese & compounds
Mercury & compounds
Methyl bromide
Methyl chloride
Methylene chloride
MDI(methylene diphenyl
CAS #
75070
107028
79061
107131
71432
100447
117817
106990
56235
7782505
67663
107062
106467
78875
542756
107062
75218
75343
50000
118741
77474
302012
7647010
108316
74873
75902
106688
A-33
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diisocyanate) 101688
Nickel & compounds
2-Nitropropane
Phosgene 75445
POM (PAHs)* *
Quinoline 91225
2,3,7, 8-TCDF/2,3,7,8-TCDD*
Tetrachloroethylene 127184
Trichloroethylene 79016
Toluene 108883
Vinyl chloride 75014
* Inventory as TEQ.
** Inventory as sum of 16 PAH and speciate. 16 PAH compounds include:
Acenaphthene, Naphthalene, Benzo(b)fluoranthene***, Acenaphthylene,
Phenanthrene, Benzo(k)fluoranthene***, Anthracene, Pyrene, Chrysene***,
Benzo (ghi)perylene, Benz (a) anthracene***, Dibenz (a,h)anthracene***,
Fluoranthene, Benzo(a)pyrene*** Indeno(1,2,3-cd)pyrene***, Fluorene
*** These 7 PAHs are carcinogenic and are usually reported as the sum of
7 PAH.
GLOSSARY
Activity rate/throughput (annual) - A measurable factor or parameter that
relates directly or indirectly to the emissions of an air pollution source.
Depending on the type of source category, activity information may refer to
the amount of fuel combusted, raw material processed, product manufactured, or
material handled or processed. It may also refer to population, employment,
number of units, or miles traveled. Activity information is typically the
value that is multiplied against an emission factor to generate an emissions
estimate.
Activity rate/throughput (daily) - The beginning and ending dates and times
that define the emissions period used to estimate the daily activity
rate/throughput.
Area classification - The Clean Air Act classification of the nonattainment
area containing the reporting source (transitional, marginal, moderate,
serious, severe, extreme).
Area sources - Area sources collectively represent individual sources that
have not been inventoried as specific point, mobile, or biogenic sources.
These individual sources treated collectively as area sources are typically
too small, numerous, or difficult to inventory using the methods for the other
classes of sources.
Annual emissions - Actual emissions for a plant, point, or process - measured
or calculated that represent a calender year.
Ash content - Inert residual portion of a fuel.
Biogenic sources - Biogenic emissions are all pollutants emitted from
non-anthropogenic sources. Example sources include trees and vegetation, oil
and gas seeps, and microbial activity.
Control device type - The name of the type of control device (e.g., wet
scrubber, flaring, or process change).
A-34
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County/parish/reservation (FIPS) - Federal Information Placement System
(FIPS). FIPS is the system of unique numeric codes the government developed
to identify states, counties, towns, and townships for the entire United
States, Puerto Rico, and Guam.
Day/wk in operations - Days per week that the emitting process operates.
Design capacity - A measure of the size of a boiler, based on the reported
maximum continuous steam flow. Capacity is calculated in units of MMBtu/hr.
Emission factor - Ratio relating emissions of a specific pollutant to an
activity or material throughput level.
Exit gas flow rate - Numeric value of stack gas's flow rate.
Exit gas temperature - Numeric value of an exit gas stream's temperature.
Exit gas velocity - Numeric value of an exit gas stream's velocity.
Fall throughput(%) - Part of the throughput for the three Fall months
(September, October, November). This expresses part of the of annual activity
information based on four seasons - typically spring, summer, fall, and
winter. It can be a percentage of the annual activity (e.g., production in
summer is 40% of the year's production) or units of the activity (e.g., out of
600 units produced, spring =150 units, summer = 250 units, fall = 150 units,
and winter = 50 units).
Federal ID code (plant) - Unique codes for a plant or facility, containing one
or more pollutant-emitting sources.
Federal ID code (point) - Unique codes for the point of generation of
emissions, typically a physical piece of equipment.
Federal ID code (process) - Unique codes for the process generating the
emissions, typically a description of a process.
Federal ID code (stack number) - Unique codes for the point where emissions
from one or more processes release into the atmosphere.
Heat content - The amount of thermal heat energy in a solid, liquid, or
gaseous fuel. Fuel heat content is typically expressed in units of Btu/lb of
fuel, Btu/gal of fuel, joules/kg of fuel, etc.
Hr/day in operations - Hours per day that the emitting process operates.
Inventory end date - Last day of the inventory period.
Inventory start date - First day of the inventory period.
Inventory type - Type of inventory represented by data (i.e., point, 3-Year
cycle, daily).
Inventory year - The calendar year for which you calculated emissions
estimates.
Maximum design rate - Maximum rate of fuel use based on the equipment's or
process' physical size or operational capabilities.
A-35
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Maximum nameplate capacity - A measure of a generator's size that the
manufacturer puts on the unit's nameplate. The data element is reported in MW
or KW.
Mobile source - A motor vehicle, nonroad engine or nonroad vehicle.
• A "motor vehicle" is any self-propelled vehicle used to
carry people or property on a street or highway.
• A "nonroad engine" is an internal combustion engine
(including fuel system) that is not used in a motor vehicle
or vehicle only used for competition, or that is not
affected by sections 111 or 202 of the CAA.
• A "nonroad vehicle" is a vehicle that is run by a nonroad
engine and that is not a motor vehicle or a vehicle only
used for competition.
NOX ozone season emissions - Actual ozone season emissions for a plant, point,
or process, either measured or calculated. Ozone season emissions for NOX SIP
Call are the emissions between May 1 and September 30. (Note that 40 CFR Part
58 contains a different definition for ozone season monitoring.}
Physical address - Street address of a facility.
Point source - Point sources are large, stationary (non-mobile), identifiable
sources of emissions that release pollutants into the atmosphere. State or
local air regulatory agencies define a plant as a point source whenever it
annually emits more than a specified amount of a given pollutant; these
"cutoff" levels definitions vary among state and local agencies. A stationary
source which emits less than a "cutoff" is an area source.
Pollutant code - A unique code for each reported pollutant assigned in the
EIIP Data Model. The model uses character names for criteria pollutants and
Chemical Abstracts Service (CAS) numbers for all other pollutants. You may be
using SAROAD codes for pollutants, but you should be able to map them to the
pollutant codes in the EIIP Data Model.
Rule effectiveness (RE) - How well a regulatory program achieves all
possible emission reductions. This rating reflects the assumption that
controls typically aren't 100 percent effective because of equipment downtime,
upsets, decreases in control efficiencies, and other deficiencies in emission
estimates. RE adjusts the control efficiency.
Rule penetration - The percentage of an area source category covered by an
applicable regulation.
SCC - Source category code. A process-level code that describes the equipment
or operation which is emitting pollutants.
Seasonal activity rate/throughput - A measurable factor or parameter that
relates directly or indirectly to the ozone season emissions of an air
pollution source. Depending on the type of source category, activity
information may refer to the amount of fuel combusted, raw material processed,
product manufactured, or material handled or processed. It may also refer to
population, employment, number of units, or miles traveled. Activity
information is typically the value that is multiplied against an emission
factor to generate an emissions estimate.
Seasonal fuel heat content - The amount of thermal heat energy in a solid,
liquid, or gaseous fuel used during the ozone season. Fuel heat content is
typically expressed in units of Btu/lb of fuel, Btu/gal of fuel, joules/kg of
fuel, etc.
A-36
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Secondary control eff (%) - The emission reduction efficiency of a secondary
control device. Control efficiency is usually expressed as a percentage or in
tenths.
Source of activity rate/throughput data - Source of data from which you got
the activity rate/throughput.
Source of emission factor - Source of data from which you got the emission
factor.
Source of fuel heat content data - Source of data from which you got the fuel
heat content.
SIC/NAICS - Standard Industrial Classification code. NAICS (North American
Industry Classification System) codes will replace SIC codes. U.S. Department
of Commerce's code for businesses by products or services.
Site name - The name of the facility.
Spring throughput(%) - Part of throughput or activity for the three spring
months (March, April, May). See the definition of Fall Throughput.
Stack diameter - A stack's inner physical diameter.
Stack height - A stack's physical height above the surrounding terrain.
Start time (hour) - Start time (if available) that you used to calculate of
emissions estimates.
State/providence/territory (FIPS) - Federal Information Placement System
(FIPS). FIPS is the system of unique numeric codes the government developed
to identify states, counties, towns, and townships for the entire United
States, Puerto Rico, and Guam.
Sulfur content - Sulfur content of a fuel, usually expressed as a percentage.
Summer throughput(%) - Part of throughput or activity for the three summer
months (June, July, August). See the definition of Fall Throughput.
Summer/winter work weekday emissions - Average day's emissions for a typical
day. Ozone daily emissions = summer work weekday; CO and PM daily emissions =
winter work weekday.
Total capture/control efficiency - The emission reduction efficiency of a
primary control device, which shows the amount controls or material changes
reduce a particular pollutant from a process' emissions. Control efficiency
is usually expressed as a percentage or in tenths.
Type A source - Very large point sources defined by emission thresholds listed
in Table 1.
Type B source - Smaller point sources defined by emission thresholds listed in
Table 1.
VMT by Roadway Class - VMT expresses vehicle activity and is used with
emission factors. The emission factors are usually expressed in terms of
grams per mile of travel. Because VMT doesn't correlate directly to emissions
that occur while the vehicle isn't moving, these non-moving emissions are
incorporated into the emission factors in EPA's Mobile Model.
A-37
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Winter throughput (%) - Part of throughput or activity for the three winter
months (December, January, February). See the definition of Fall
Throughput.
Wk/yr in operation - Weeks per year that the emitting process operates.
Work Weekday - Any day of the week except Saturday or Sunday.
X stack coordinate (latitude) - An object's east-west geographical coordinate.
Y stack coordinate (longitude) - An object's north-south geographical
coordinate.
A-38
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Subpart Q - [Amended]
3. Section 51.322 is revised to read as follows:
§51.322 Sources subject to emissions reporting.
The requirements for reporting emissions data under the plan are in
§51.001 of part 51 of this chapter.
4. Section 51.323 is revised to read as follows:
§51.323 Reportable emissions data and information.
The requirements for reportable emissions data and information under the
plan are in subpart A of part 51 of this chapter.
A-39
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TECHNICAL REPORT DATA
(Please read Instructions on reverse before completing)
1 REPORT NO 2
EPA-454/R-99-006
4 TITLE AND SUBTITLE
Emission Inventory Guidance for Implementation of Ozone and Paniculate
Matter National Ambient Air Quality Standards (NAAQS) and Regional Haze
Regulations
7 AUTHOR(S)
Emission Factor and Inventory Group
9 PERFORMING ORGANIZATION NAME AND ADDRESS
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Emissions Monitoring and Analysis Division
Emission Factor and Inventory Group
Research Triangle Park, NC 27711
12 SPONSORING AGENCY NAME AND ADDRESS
Director
Office of Air Quality Planning and Standards
Office of Air and Radiation
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
3 RECIPIENT'S ACCESSION NO
5 REPORT DATE
April 1999
6 PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO
10 PROGRAM ELEMENT NO
11 CONTRACT/GRANT NO
68-D7-0067, Work Assignment 2-07
E. H. Pechan
13 TYPE OF REPORT AND PERIOD COVERED
Guidance Document
June 1998 - April 1999
14 SPONSORING AGENCY CODE
EPA/200/04
15 SUPPLEMENTARY NOTES
Contact Person: William B. Kuykendal (919) 541-5372
16 ABSTRACT This document provides guidance to State and local agencies for the development of emission inventories. This
guidance is specifically for emission inventories developed for ozone and PM25 State Implementation Plans (SIPs). Topics
covered by this guidance include: types of inventories, specification of Base Year, inventory approval, pollutants to be
inventoried, sources to be inventoried, geographic coverage, temporal basis of the inventory, data reporting requirements, and
quality assurance and inventory documentation.
17 KEY WORDS AND DOCUMENT ANALYSIS
a DESCRIPTORS
emission inventory, ozone, paniculate matter, regional
haze, guidance
18 DISTRIBUTION STATEMENT
Release Unlimited
b IDENTIFIERS/OPEN ENDED TERMS c COSATI Field/Group
19 SECURITY CLASS (Report) 21. NO OF PAGES
Unclassified 116
20 SECURITY CLASS (Page) 22 PRJCE
Unclassified
EPA Form 2220-1 (Rev. 4-77) PREVIOUS EDITION IS OBSOLETE
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