United States Office of Air Quality February 1990
Environmental Protection Planning and Standards
Agency Research Triangle Park, NC 27711
&EPA Guidance for Initiating
Ozone/CO SIP Emission
Inventories Pursuant to
the 1990 Clean Air Act
Amendments
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GUIDANCE FOR INITIATING OZONE/CO SIP EMISSION
INVENTORIES PURSUANT TO THE
1990 CLEAN AIR ACT AMENDMENTS
Prepared for:
Emission Inventory Branch
Technical Support Division
Office Of Air Quality Planning And Standards
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
Prepared by:
Radian Corporation
3200 Progress Center
Post Office Box 13000
Research Triangle Park, North Carolina 27709
February 13, 1991
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DISCLAIMER
This report has been reviewed by the Office of Air Quality Planning and
Standards, U. S. Environmental Protection Agency, and has been approved for
publication as received from the contractor. The contents reflect the views and policies
of the Agency, but any mention of trade names or commercial products does not
constitute endorsement or recommendation for use.
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ACKNOWLEDGEMENT
The National Air Data Branch (NADB) of the U.S. Environmental
Protection Agency's (EPA's) Office of Air Quality Planning and Standards (OAQPS) is
gratefully thanked for providing the necessary guidance on data management and
reporting requirements.
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EXECUTIVE SUMMARY
After considerable legislative debate and negotiation, a new Clean Air Act
Bill was passed by Congress in October 1990 and signed into law by President Bush on
November 15, 1990. The Bill is known as the Clean Air Act Amendments (CAAA) of
1990. November 15, 1990 is considered the date of enactment of the CAAA. Title I of
the CAAA addresses the topic of nonattainment with national ambient air quality
standards (NAAQS), including standards for ozone and carbon monoxide (CO). Ozone
and CO nonattainment areas and their respective State Implementation Plan (SIP)
emission inventories are the focus of the discussion in this guidance document.
Under the CAAA, States will have a large responsibility to inventory
emissions contributing to NAAQS nonattainment, to track these emissions over time, and
to ensure that control strategies are being implemented that reduce emissions and move
areas towards attainment. In regards to emission inventories, the requirements of Title I
continue and embellish many of the programs initiated under the previously proposed
Post-1987 Ozone/CO Policy (52 FR 45044). However, the amendments also contain
several specific requirements pertaining to emission inventory development that are new
or that supersede those contained in the previous proposed policy. The basic purpose of
this document is to provide States with an overview of the emission inventory
requirements resulting from the CAAA of 1990 and to contrast these requirements with
those contained in the previously proposed Post-1987 Policy. In addition to summarizing
the inventory implications of the new Act, this document also contains a timeline that
States should use as a planning tool for the preparation and submittal of their base year
inventories and a discussion of new guidance that EPA will be issuing to support the
requirements of the CAAA.
For ozone and CO, the CAAA establish nonattainment area classifications
and inventory requirements ranked according to the severity of the area's air pollution
problem. The extent of an area's inventory requirements is directly relatable to the
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degree that it exceeds the respective ozone or CO NAAQS. For ozone, there are five
nonattainment classifications known ^as Marginal, Moderate, Serious, Severe, and
Extreme. The classifications are based on ranges of ozone design values. The
classifications are summarized below by design value and required attainment date.
Ozone Nonattainment Classifications
Area Class
Design Value toom}
Marginal
0.121 up to 0.138
Moderate
0.138 up to 0.160
Serious
0.160 up to 0.180
Severe
0.180 up to 0.280
Extreme
0.280 and above
Attainment Date
3 years after enactment (Nov. 15, 1993)
6 years after enactment (Nov. 15, 1996)
9 years after enactment (Nov. 15, 1999)
15 years after enactment (Nov. 15, 2005)"
20 years after enactment (Nov. 15, 2010)
'The date for attainment for Severe areas with design values between 0.190 up to 0.280
is November 15, 2007 [Section 181 (a)(2)].
Two classifications are contained in the CAAA for CO nonattainment
areas, Moderate and Severe. The design values and attainment dates for these
classifications are listed as follows.
CO Nonattainment Classifications
Area Class Design Value (ppnrt Attainment Date
Moderate 9.1 to 16.4 December 31, 1995
Serious 16.5 and above December 31,2000
The number and type of emission inventories that are required for an area
under the CAAA is a function of the nonattainment classification the area falls into.
Several different types of inventories are either explicitly or implicitly required in the
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CAAA. For ozone, there are essentially four different kinds of inventories that are
needed: 1) base year inventory; 2) "periodic inventory; 3) Reasonable Further Progress
(RFP) projection inventory; and 4) modeling inventory. The base year inventory is the
primary inventory from which all of the other three are derived. For CO nonattainment
areas, three principal types of inventories exist. These include: 1) base year inventory;
2) periodic inventory; and 3) modeling inventory. As with ozone, all of the subsequent
CO inventories have their origin in the base year inventory. The requirements and
applicability of each of these ozone and CO inventories are described in detail in this
document.
This document focuses on the base year inventory. Generally, a 1990 base
year inventory will be required. States should begin the preparation of their 1990 base
year inventories immediately even though additional guidance from EPA is still
forthcoming. States should initiate data collection activities for point sources now and
begin determining how inventories possibly prepared under the proposed Post-1987
Policy may be useful to the effort. States that prepare and submit 1987, 1988, or 1989
base year inventories mav be able to update portions of the previous inventory to 1990 to
satisfy the 1990 base year inventory requirements. States should work through their
respective EPA Regional office to determine if updating will be allowed. General
factors to consider when conducting updates for point, area, and mobile sources are
discussed in the document.
For CAAA base year inventories, EPA is requiring that States prepare an
Inventory Preparation Plan (IPP) as a first step in the process of developing the
1990 base year inventories. The plans should be brief but should describe how the
agencies involved in preparing the inventories intend to develop, document, and submit
their inventories. The basic point of having the plans will be to give States the
opportunity to tell EPA upfront how they plan to compile the required inventories and
allow for EPA feedback in an effort to avoid States using approaches that are
unacceptable to EPA. States need to be aware that EPA will not accept a base year
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inventory for review from a State until EPA has received, reviewed, and approved of an
IPP for that inventory. States should .begin preparing IPPs immediately based on the
guidance provided in this report.
With a few exceptions, States will be able to compile 1990 base year
inventories using much of the procedural guidance issued in connection with the
proposed Post-1987 Policy. Most of the primary features such as the pollutants of
concern, the source types of concern, and the application of rule effectiveness are
virtually unchanged from the previous guidance. Two items that are changed, however,
are the requirement to include biogenic emissions and the need to use an updated
version of MOBILE4, for mobile source estimates. Biogenic emissions estimates are
required for all ozone nonattainment areas. EPA will supply States with the means to
determine biogenic emissions. In May 1991, EPA plans to release MOBILE4.1, a
revised version of its mobile source emission factor model. The updated model replaces
MOBILE4 and will be required in the development of all 1990 base year inventories.
Base year inventories developed and submitted under the CAAA will also
be required to conform to more standardized and rigorous reporting and documentation
provisions than previous inventories. The written report summarizing the inventory
results and documenting how the results were compiled, and the computerized data
management aspects of inventory development will both be more scrutinized by EPA for
1990 inventories. All ozone/CO SIP inventory data submitted to EPA under 1990
CAAA requirements must be in an Aerometric Information Retrieval System
(AIRS)-compatible format in order for it to be acceptable. A description of EPA's
planned reporting and data management provisions is provided in this document.
The general timeline established by EPA for the preparation and submittal
of the 1990 base year inventories is shown in Figure 1. States should begin preparing
IPPs and collecting point source emission estimation data by February 1991. Area and
mobile source emission estimation work should begin by July 1991. Complete draft base
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year emission inventories will be accepted for review as early as January 1, 1992, but
they must be submitted by May 1, 1992 at the latest. The point source portion of the
inventories must be completed and submitted for review in the period of January -
March 1992. After receiving EPA comments, States need to revise the inventories and
submit them in final form by November 15, 1992.
As indicated in Figure 1, EPA plans on issuing additional guidance to
States on various inventory aspects during the spring/summer of 1991. This guidance
will address such items as emission inventory requirements, development of inventories
to support urban airshed modeling, area and mobile source emission estimation
procedures, emissions projections, and the use of MOBILE4.1.
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Issue
Area/Mobile
Guidance
Issue Inventory
Requirements
Documents
(For 03 * CO)
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Slates Begin
Slate* Begin
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(Nov. 16, *00)
OMS Issues
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-yr
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Slate* Begin SiixnltUng
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Inventory Reviews
|§§ Emission Inventory Branch Activities
~ Title I Requirements
¦Flnir CO/CO El Oua
03 SIPs Require
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4-yr
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8 Yr RFP Plan
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X
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Oua w/ Modeling El
(Serious ~)
Attainment Demo Due
(Moderate Areas)
Emission Statements
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(for CY 03)
Figure 1. Title I Ozone/CO Emission Inventory Timeline
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TABLE OF CONTENTS
Page
DISCLAIMER ii
ACKNOWLEDGEMENT iii
EXECUTIVE SUMMARY iv
1.0 BACKGROUND AND PURPOSE 1
2.0 OVERVIEW OF EMISSION INVENTORY REQUIREMENTS
UNDER TITLE I OF THE CAAA 4
2.1 Nonattainment Classifications 4
2.2 Emission Inventory Delineations and Definitions 6
2.2.1 Ozone Nonattainment Inventories 6
2.2.2 CO Nonattainment Inventories 11
2.2.3 Summary of Inventory Requirements 13
3.0 IMPACT OF CAAA ON THE PROPOSED POST-1987 03/C0 POLICY
AND GUIDANCE 19
3.1 Primary Pollutants of Interest 19
3.2 Source Types to be Inventoried 19
3.3 Inventory Base Year 20
3.4 Point Source Inventory Guidance 21
3.5 Area and Mobile Source Inventory Guidance 25
3.6 Major Sources in the 25-Mile Boundary 26
3.7 Temporal Basis of Emissions 27
3.8 Rule Effectiveness 28
3.9 Emissions Projections 28
3.10 Quality Assurance Plans 29
3.11 Updating Previous 1987/1988 Base Year Inventories 30
3.11.1 Point Sources 31
3.11.2 Area and Off-Highway Mobile Sources 33
3.11.3 Highway Mobile Sources 34
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TABLE OF CONTENTS
Page
4.0 NEW INVENTORY REQUIREMENTS UNDER THE CAAA 35
4.1 Inventory Preparation Plans 35
4.2 Emissions Statements 40
4.3 Biogenic Emissions Estimates 41
4.4 Emissions "Backcasting" 42
4.5 Use of NO^ Reductions to Substitute for VOC
Reduction Requiremerrs 43
4.6 Release and Required Use of an Updated MOBILE4
Model 44
4.7 Written Inventory Reporting and Documentation
Requirements 44
4.8 Computerized Data Management and Reporting 52
4.8.1 Point Source Inventory 53
4.8.2 Area and Mobile Source Inventory 61
4.8.3 Format for Area and Mobile Source Data 63
4.9 Statewide Point Source Emission Inventories for Regional
Modeling 63
5.0 PLANNED MILESTONES AND SCHEDULES 65
6.0 ADDITIONAL GUIDANCE TO BE ISSUED BY EPA 70
7.0 EXISTING EPA GUIDANCE FOR OZONE/CO EMISSION
INVENTORIES 75
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1.0 BACKGROUND AND PURPOSE
In 1989 sweeping revisions to the Clean Air Act were proposed that were
designed to curb three major threats to the nation's environment and to the health and
welfare of millions of Americans: urban air pollution, toxic air emissions, and acid rain.
The proposal also called for establishing a national permits program to make the law
more workable, and an improved enforcement program to help ensure better compliance
with the new Act provisions. A new Clean Air Act Bill was enacted on November 15,
1990 and is known as the Clean Air Act Amendments (CAAA) of 1990.
The CAAA of 1990 create a new, balanced strategy for the Nation to
attack the problem of urban air pollution. Overall, the new law reveals the Congress's
high expectations of the States and the Federal government (EPA). Title I of the CAAA
addresses the problem of nonattainment with national ambient air quality standards
(NAAQS), including standards for ozone and carbon monoxide (CO). While it gives
more time to attain the NAAQS, up to 20 years for ozone in Los Angeles, it also
requires States to make constant progress in reducing emissions. It requires the Federal
government to reduce emissions from automobiles, trucks, and buses: from consumer
products such as hair spray and window washing compounds; and from ships and barges
during loading and unloading of petroleum products. The Federal government must also
develop the technical guidelines that States need to control stationary sources. States
will have a large responsibility to inventory emissions contributing to NAAQS
nonattainment, to track these emissions over time, and to ensure that control strategies
are being implemented that reduce emissions and move areas closer to attainment.
In terms of these activities for States, the requirements of Title I essentially
continue and embellish many of the programs initiated under the previously proposed
Post-1987 Ozone/CO Policy (52 FR 45044, November 24, 1987), particularly in regards
to compiling emission inventories. The CAAA contain several specific requirements
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pertaining to emission inventory development, all of which supersede those contained in
the previously proposed Post-1987 Policy and its associated guidance materials. The
CAAA duplicate some of the proposed Post-1987 policies and guidance, modify some of
the material, and contain several new elements not found in the Post-1987 Policy. Under
the CAAA, a State's emission inventory obligations are generally related to its relative
ozone/CO nonattainment classification and the extent of emissions reduction that must
occur in order for an area to come into attainment. Simply stated, the higher above the
NAAQS an area's ozone/CO concentrations are, the greater its emission inventory
requirements.
Since States will be facing increased emission inventory responsibilities
under the CAAA, EPA will be producing additional guidance to aid States in
understanding and responding to the new requirements. Tile basic purpose of this
discussion Is to provide States with an overview of the emission inventoxy requirements
of the CAAA of 1990 and to contrast these requirements with^tibse contained in the
previouslyproposed Post-1587 Policy, In addition to summarizing the inventory
implications of the new Act, this discussion will preliminarily communicate to States
EPA's expectations and requirements in regards to inventory preparation and submittal.
The discussion also directs States as to what parts of their required inventories they
should be initiating; describes the CAAA and EPA schedules that have been specified
for inventory development and submittal, guidance preparation, and training; and
describes the types of inventory-related guidance that is planned by EPA for 1991 to help
States respond to the new Act and its inventory requirements.
The intent of providing this information to States now and in this form is
to alert States as quickly as possible to the kinds of ozone/CO inventory requirements
and challenges they will be facing under the CAAA and of EPA's expectations
concerning activities necessary to fulfill those requirements. It should be noted, however,
that for some of the inventory questions, final policy decisions and guidance are not yet
available, and thus, these areas are not extensively covered in this discussion. EPA is
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aggressively working on all unresolved questions and is committed to finalizing decisions
on all fronts in the next several months. Specifics on this are covered in Section 6.0. As
final policies and guidance become available, EPA will communicate them to States.
Subsequent guidance material issued by EPA will not cause States to have to re-do
efforts that were initiated by this guidance document.
The subsequent discussion is divided into six sections. These sections
address: 1) an overview of Title I of the CAAA (Section 2.0), 2) impacts of the CAAA
on the proposed Post-1987 Policy and related guidance (Section 3.0), 3) new inventory
requirements under the CAAA (Section 4.0), 4) planned inventory schedules and
milestones (Section 5.0), 5) additional guidance that is forthcoming for inventory
development under the CAAA (Section 6.0), and 6) existing EPA guidance that is
available on ozone/CO SIP inventory development (Section 7.0). Questions regarding
specific aspects of the emissipn inventory information in this discussion should first be
directed to the respective Regional Office contact person for ozone/CO emission
inventories. If additional information is required, contact the Chief, Inventory Guidance
and Evaluation Section, Emission Inventory Branch (MD-14), Technical Support
Division, U.S. Environmental Protection Agency, Research Triangle Park, North
Carolina, 27711. The telephone number is (919) 541-5575 (FTS 629-5575). Questions
on EPA policy and the overall requirements for ozone and CO SIPs should be directed
to the Chief, Ozone/CO Policy Development Section, Ozone/CO Programs Branch
(MD-15), Air Quality Management Division, U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina, 27711. The telephone number is (919) 541-5517
(FTS 629-5517).
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2.0 OVERVIEW OF EMISSION INVENTORY REQUIREMENTS
UNDER TITLE I OF THE CAAA
2.1 Nonattainment Classifications
For ozone and CO, the CAAA establish nonattainment area classifications
and inventory requirements ranked according to the severity of the area's air pollution
problem. For tliere are live nonattataiBeiti known as Marginal,
Moderate, Serious, Severe, aiid Extreme [Section 181(a)]. The classifications are based
on ranges of ozone design values developed over the time period 1987 to 1989. Each of
the 96 areas currently designated as being in nonattainment of the ozone National
Ambient Air Quality Standard (NAAQS) has been placed into one of the classifications.
The design value ranges and the attainment date for each classification are given below
[Section 181(a) (1),(2)].
Ozone Nonattainment Classifications
Area Class Design Value (ppm^ Attainment Date
Marginal 0.121 up to 0.138 3 years after enactment (Nov. 15, 1993)
Moderate 0.138 up to 0.160 6 years after enactment (Nov. 15, 1996)
Serious 0.160 up to 0.180 9 years after enactment (Nov. 15, 1999)
Severe 0.180 up to 0.280 15 years after enactment (Nov. 15, 2005)'
Extreme 0.280 and above 20 years after enactment (Nov. 15, 2010)
"An exception is made to the schedules for attainment dates above for Severe areas with
design values between 0.190 up to 0.280 based on 1986-1988 air quality data [Section
181(a)(2)]. For these areas, the attainment date is 17 years after enactment or
November 15, 2007.
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Two classifications are contained in the CAAA for CO nonattainment
areas. These two groupings, kaowiwis Moderate and Serious* are defined as follows
[Section 186(a)(1)].
CO Nonattainment Classifications
Area Class
Moderate
Serious
Design Value fppm^
9.1 to 16.4
16.5 and above
Attainment Date
December 31, 1995
December 31, 2000
Even though they are still classified as Moderate areas, CO nonattainment
areas with design values greater than 12.7 ppm have more stringent requirements than
do Moderate areas with values in the 9.1 op to 12.7 range (Section 187). The extra
requirements involve compiling additional vehicle miles travelled (VMT) projections [187
(a)(2)(A)], preparing contingency plans if projected VMT levels are not met and
attainment is not achieved [187 (a)(2)(B)(3)], establishing enhanced vehicle inspection
and maintenance (I/M) programs [187 (a)(2)(B)(6)], and preparing specific plans to
demonstrate that attainment and necessary annual emission reductions will be met [187
(a)(2)(B)(7)].
Two 1-year extensions for reaching ozone or CO attainment are available
to States if: 1) all SIP requirements and commitments for an area were met and 2) no
more than one exceedance of the ozone or CO NAAQS occurred in the year preceding
the extension year [Section 181 (a)(5) and Section 186 (a)(4)].
The emission inventories required to be compiled under each ozone and
CO classification are presented in Section 2.2.
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2.2
Emission Inventory Delineations and Definitions
The type and number of emission inventories that are required under the
CAAA is generally a function of the nonattainment category an area falls into. Basic
inventory types required either explicitly or implicitly in the CAAA are described below.
22.1 Ozone Nonattainment Inventories
For ozone nonattainment areas, there are essentially fear basic kinds of
inventories that are reqntred under the CAAA. These four are identified as:
• Base year inventory,
• Periodic inventory,
• Reasonable Further Progress (RFP) Projection inventory, and
• Modeling inventory.
"Tbe-j the
other three i^uir^ inventories are derived. It serves as the basis of the emissions
configuration for a nonattainment area. The CAAA call for this inventory to be a
comprehensive, accurate, and current inventory of actual emissions [Section 182(a)(1)].
The inventory shall include emissions of VOC, NO*, and CO from stationary point and
area sources, highway mobile sources, and non-highway mobile sources. Both
anthropogenic and biogenic emission sources shall be included in the inventory.
Emissions are to be based on conditions that exist during the peak ozone season
(generally summertime) of the year of enactment of the CAAA, i.e., 1990. Industrial
activity, population, VMT, etc. and emissions must represent a typical peak ozone season
weekday for the base year 1990.
The term "typical ozone season weekday" refers to activities that occur
during the summer on weekdays, averaged on a daily basis. For example, if during the
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summer weekdays of 1990 (Monday - Fridays, June - August) a manufacturing process
produces 12,000 tons of material, and this period includes 13 weeks, 5 weekdays per
week, then the average or "typical" ozone season weekday activity would be:
12,000/(13 x 5) = 185 tons/day. This value would then be multiplied by the emission
factor, control factor, and rule effectiveness factor, if applicable, to calculate the typical
ozone season weekday emissions.
Emissions and related activities shall also be reported on an annual
average basis for 1990 for documentation purposes. Temperatures to be used in
evaporative loss estimate calculations should be drawn from the mean of those occurring
during the highest ozone exceedance episode days over the last three to four years.
More specific guidance concerning temperature calculations will be issued by May 1991.
lie CAAA require moderate, serious, severe, and extreme caone
nonattainroent areas to submit a plan within threeyearsoftle date of enactment to
reduce VOC emissions by 15'percent withmsiryearsafterenactment, A baseline level
of emissions, from which the 15 percent reduction is calculated, is determined by
adjusting the base year inventory to exclude biogenic emissions and to exclude certain
emission reductions not creditable towards the 15 percent. The adjusted base year
inventory represents the inventory that is the basis from which the 15 percent reduction
is then calculated. The adjusted base year inventory equals the base year inventory
minus biogenic emissions, emission reductions from Federal Motor Vehicle Control
Program (FMVCP) regulations promulgated prior to January 1, 1990, and emission
reductions from RVP rules promulgated prior to CAAA enactment or required under
CAAA Section 211(h). Only VOC and NOx emissions have to be addressed in adjusted
inventories [Section 182 (b)(1)(B)].
KteaSftimMg Further Pnreresa flffPV inventories are necessary
under the CAAA for demonstrating strategies by whiehthere
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show how the required 15 percent emission reduction over the first six years after
enactment will be achieved [Section 182 (b)(1)(A) and (c)(2)(B)]. This requirement
applies to ozone nonattainment areas classified as moderate or above. The base year for
this projection inventory is 1996 and it must be submitted in final form by November 15,
1993. In addition to the projection for 1996, emission projections should be summarized
for intermediate years (1991 through 1995). More information on the content and
format of the 1996 RFP projection inventory and intermediate year projection summaries
will be included in RFP projection guidance to be issued in November 1991.
The 1996 projection inventory is to be based on allowable rates of
emissions, activity, etc. for both VOC and NOx rather than assuming the current rates
will be maintained in the future year. These allowables are to be determined by what is
dictated by instituted regulatory limits. For example, for a SIP regulation limiting a
furniture manufacturer to 0.05 lbs of VOC used per gallon of coating applied, the
allowable solvent content of the coating should be used to calculate emissions in year 6,
even if a specific manufacturer is currently using only 0.02 lbs VOC/gallon coating.
Because activity levels for this example (gallons coating applied per day or per year) are
not limited by regulations, they would be determined by applying base year activity levels
against growth factors approved by EPA. For evaporative loss emission sources where
temperature is used in the calculation of emissions, the projection inventory should use
the same temperatures used in the base year inventory. Future year effects of the
FMVCP must be modeled using an updated version of MOBILE4 that will be issued in
May 1991. In the case of California, an approved mobile model based upon the State's
program would be used.
tfetAAA farther require that serious, severe, and extremeozone
nonattainment areas demonstrate thai VOC emissions will be reduced by at least 3
percent per year (is addition to the Initial ISpercent reductions) ateragedover each 3-
year period beginning slxyears after enactment andlasting ontil attainment is reached.
RFP Projection inventories are also used to demonstrate how these continued reductions
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will be achieved. As with the 1996 percent RFP projection inventory, projection
summaries are required for years prior to the end of each 3-year interval and like the
1996 RFP projection inventory, the 3 year 3 percent projection inventories are based on
allowable emissions, activity levels, etc. established by statutory regulations rather than
current emissions. If activity levels are limited by regulation, then the upper limit is used
to project emissions. If not regulated, then the current actual activity level must be
multiplied by EPA-approved growth factors to calculate projected activity levels. As was
specified for the year 6 projection inventory, evaporative loss emission sources should
apply the same temperatures used in the base year inventory for the 3 year 3 percent
projection inventories. These projection inventories, in conjunction with periodic
inventories, will be used to track RFP achievement. More information on projection
inventories and projecting emissions will be provided in projections guidance to be
completed in July 1991, and in RFP tracking guidance to be completed in November
1991.
Periodic Inventories are required to be compiled aaderi; the^CAAA: by all
classifications of ozone nonattaiiunent areas [Section 182 (a)(3)(A)]; Periodic
inventories are to be based on actual emissions and shall cover VOC and NOx emission
sources. Like the base year inventory, periodic inventories are to be based on peak
ozone season temperatures, industrial activity, etc. [Annual activity and/or emissions
data must also be provided with the inventory for documentation purposes.] The base
year for the first periodic inventory will be 1993. Thereafter, the base year will be every
third year, e.g., 1996, 1999, etc. The primary function of the periodic inventories is to
track emission reductions, particularly relating to RFP requirements. For serious areas
and above, the CAAA require that 6 years after the date of enactment and every 3 years
thereafter, States shall demonstrate that the RFP reduction requirements were met
[Section 182 (g)(1)]. This will be accomplished at least in part by comparing the
periodic inventories to base year 1990 inventories to ensure that emissions were reduced
during the preceding intervals equivalent to the total emission level required to be
achieved by the end of the interval.
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The final version of each periodic inventory is required to be submitted no
later than the end of each 3-year period after submission of the final base year inventory,
until the area is redesignated to attainment [Section 182 (a)(3)(A)]. However, because
the periodic inventories will be used in part to demonstrate whether or not the RFP
reduction requirements were in fact met, these inventories must be submitted as close to
each milestone date as is feasible. More information will be provided on periodic
inventories in guidance on RFP tracking to be completed in November 1991.
must be compiled for ozone nonattainment areas
where- photochmical ^d raodeling is required (Ue., serious areas and above and multi-
state mod^te areas) (Section 182 (c)(2)(A) and 182 (|)(1)(B)| and where modeling is
necessary for demonstration of attainment bat photochemical grid modeling is not
specifically required (Le^ moderate areas that are not part of a multi-state region)
[Section 182 (b)(1)(A)]. Both a base year and a projected modeling inventory are
needed. For the photochemical grid modeling inventories, hourly emission estimates will
be required that are specific to the designated peak ozone episodic days. The designated
days will be defined using guidance on the application of the Urban Airshed Model
(UAM) to be issued in May 1991. Designated day temperatures will be required to
estimate emissions properly. For areas needing to perform some type of an attainment
demonstration but that are not specifically required to perform photochemical grid
modeling (i.e., moderate areas in non multi-state regions), the 1990 base year emission
inventory rates can be used after conversion to an hourly basis.
For modeling inventories, VOC, NO^ and CO emissions are to be
inventoried from anthropogenic and biogenic sources. Emissions have to be temporally
allocated, speciated, and spatially gridded for the purposes of photochemical modeling.
The base year modeling inventory will use actual emission rates. The emission rates,
while not necessarily identical, should be consistent with those developed for the 1990
base year inventory unless episode days for years other than 1990 are to be modeled.
For those cases, significant adjustments to the inventory should be reflected (e.g., if 1988
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is modeled, 1988 VMT should be used). It should be noted that the geographical area
for the modeling inventory will extend beyond the geographic boundaries of the
particular nonattainment area.
The projected modeling inventory will use allowable emission rates dictated
by regulatory limits. The rates should be consistent with those found in the RFP
tracking projection inventory for the year of attainment. Additional guidance will be
forthcoming on how to run the updated MOBILE4 emission factor model to produce
hourly mobile source emission estimates needed for photochemical gr modeling. This
guidance will be issued in May 1991.
122 CO Nonattainment Inventories
For CO nonattainment areas, (he requirementsLof Uie CAAA necessitate
that three types of emission Inventories be assembled. Tbese%hree types include base
year inventories, periodic inventories, and modeling inventories (Section 187 (a)(1),
(a)(5), (a)(7), and 187 (d)(1)]. The base year inventory is the primary inventory from
which all other CO inventories are derived. It establishes the basis for determining rate
of progress requirements, and is used as the basis for periodic inventories and attainment
demonstrations. The base year CO inventory is defined in the CAAA to be a "current
inventory." EPA interprets this to mean an inventory for 1990 (year of enactment). The
inventory is to address actual CO emissions during the peak CO season for the area. All
stationary point and area sources and highway/non-highway mobiles sources are to be
included in the compilation. Peak CO season should reflect the months when peak CO
air quality concentrations occur. For many, but not all, areas of the country, the peak
CO season will be in the wintertime months. For areas where winter is the peak CO
season, the 1990 base year inventory will include the winter months beginning in 1989
and extending into 1990 (e.g., December 1989 and January-February 1990). Emissions
are to be based on peak 8-hour period emissions during the designated CO season. The
peak 8-hour period of emissions is determined by the peak air quality violations.
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Periodic CO inventories essentially require the same information as the
base year inventory. The primary difference between them is the basis year for the
inventory. The first periodic inventory must be based on 1993 information
[Section 187 (a)]. It is due in final form no later than September 30, 1995, and
subsequent ones no later than the end of each 3-year period thereafter until the area is
redesignated to attainment [Section 187 (a)(5)]. Periodic CO inventories are to address
actual CO emissions during the CO season on a peak 8-hour basis. Periodic inventories
will play a role in Milestone Demonstrations. More guidance on this role will be
forthcoming in March 1991.
Similar to ozone, modeling inventories are necessary for CO because of
CAAA provisions that require Attainment Demonstrations to be made for certain CO
nonattainment areas [Section 187 (a)(7) and 187 (d)(1)]. Moderate areas exceeding a
design value of 12.7 ppm must submit an attainment plan before November 15, 1992 that
projects how attainment will be achieved by December 31, 1995. The same requirement
exists for serious areas except that attainment must be demonstrated by December 31,
2000. Base year and projected modeling inventories will be needed. The precise type of
inventory required and its level of detail will be dictated by whether a proportional
rollback approach can be used or gridded dispersion modeling is required. EPA will
provide direction to States on this question for specific nonattainment areas in the
future.
As with the ozone modeling inventories, the CO base year modeling
inventory represents actual emissions in the base year CO season. Emissions would be
determined for the peak 8-hour period during the peak CO season. All stationary point
and area sources and all mobile source types must be included in the inventory. Activity
levels and production data used to calculate emissions should represent actual data.
Conversely, the projection modeling inventory would be based on allowable emissions
dictated by regulatory limits, and not actual emissions. The emission levels in effect will
represent the results the State expects from its SIP control strategies. Activity levels
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used to estimate emissions should be those expected in the future attainment year (i.e.,
1995 for moderate areas or 2000 for-serious areas).
22.3 Summary of Inventory Requirements
The types of inventories that are required to be compiled under each
different nonattainment categorization are delineated below. Requirements for
Emissions Statements are also summarized.
Ozone Nonattai Tient Areas
Marginal Areas:
a)
b)
c)
13
Base Year Inventory -- Required by November 15, 1992, base year
is 1990, includes actual emissions of VOC, NOx, and CO. An
adjusted base year inventory is also required by November 15, 1992,
and serves as the starting point for emission reduction calculations.
The adjusted base year inventory equals the 1990 base year
inventory less biogenic emissions and specific exclusions for emission
reductions achieved from RVP regulations promulgated prior to
enactment and the FMVCP prior to January 1, 1990.
Emissions Statements -- State required by November 15, 1992 to
revise SIP to require owner/operator of sources of VOC and NOx
(with emissions > 25 tons/yr) to provide statement showing actual
emissions, must verify that the data are accurate, first submission by
November 15, 1993 and annual updates thereafter.
Periodic Inventory ~ Required no later than November 15, 1995,
however, must be submitted as soon after the end of the base year
as is feasible. Base year for inventory is 1993. (If attainment is not
demonstrated by 1993, the area is bumped up to the Moderate
classification level and must comply with all of the inventory
requirements of that classification.)
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Moderate Areas:
a) Base Year Inventory -- Same requirements as Marginal Area
b) Emissions Statements -- Same requirements as Marginal Area
c) Periodic Inventory -- Same requirements as Marginal Area except a
periodic inventory is due every three years after the initial submittal
until the area is redesignated to attainment (base years are 1993 and
1996).
d) RFP Projected Inventory for Year 6 (1996) - Inventory takes the
adjusted base year inventory and projects it into the future to 1996
to demonstrate that the required 15 percent reduction will be
achieved. The inventory includes VOC and NOx emissions, and is
based on allowable emissions dictated by regulatory limits. The
base year for the projection inventory is 1996 and it has to be
submitted in final form by November 15, 1993. In addition,
inventory projections must be summarized for intermediate years
(1991-1995) and submitted with the 1996 projection.
e) Modeling Inventory -- By November 15, 1993, the State must make
a demonstration that its plan provides for attainment by the
applicable date. To make the Attainment Demonstration, base year
and projected modeling inventories are needed. The base year
modeling inventory will be derived from the 1990 base year
inventory but must reflect significant changes in conditions and
activities of the episode days, while the projected modeling
inventory will have a 1996 base year. The projected modeling
inventory will be used to determine if the proposed SIP control
strategies are adequate to reach attainment by the designated date.
Serious Areas:
a) Base Year Inventory - Same requirements as Moderate Area
b) Emissions Statements -- Same requirements as Moderate Area
c) Periodic Inventory - Same requirements as Moderate Area (base
years are 1993, 1996, and 1999)
d) RFP Projected Inventory for Year 6 (1996) - Same requirements as
Moderate Areas
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e) RFP Projected.Inventory for Year 9 (1999) -- By November 15, 1994
the State must submit an inventory that projects how the 3 percent
per year RFP reduction requirement over 3 years (years 1996-1999)
will be achieved. The inventory includes VOC and NOx emissions,
and is based on allowable emissions dictated by regulatory limits.
Projections must be summarized for intermediate years (1997-1999).
f) Modeling Inventory -- By November 15, 1994, the State must make
a demonstration that its plan provides for attainment by the
applicable date. To make the Attainment Demonstration, base year
and projected modeling inventories are needed since the CAAA
require that photochemical grid modeling or EPA-approved
alternative be used. The base year modeling inventory will be
derived from the 1990 base year inventory but must reflect
significant changes in conditions and activities of the episode days,
while the projected modeling inventory will have a 1999 base year.
Both inventories will require considerably more detailed data than
either the 1990 base year or the projected base year inventory. The
projected modeling inventory will be used to determine if the
proposed SIP control strategies are adequate to reach attainment by
the designated date.
Severe Areas:
a) Base Year Inventory - Same requirements as Serious Area
b) Emissions Statements -- Same requirements as Serious Area
c) Periodic Inventory - Same requirements as Serious Area (base
years are 1993, 1996, 1999, 2002, and 2005. For areas over
0.190 ppm, an additional inventory for 2007 would be required.)
d) RFP Projected Inventory for Year 6 (1996) - Same requirements as
Serious Areas
e) RFP Projected Inventory for Year 9 (1999) -- Same requirements as
Serious Area
f) RFP Projected Inventory for Year 12 (2002) - By November 15,
1994 the State must submit an inventory that projects how the
3 percent per year RFP reduction requirement over 3 years (years
1999-2002) will be achieved. The inventory includes VOC and NOx
emissions, and is based on allowable emissions dictated by
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regulatory limits. Projections must be summarized for intermediate
years.
g) RFP Projected Inventory for Years 15 (2005) -- By November 15,
1994 the State must submit an inventory that projects how the 3
percent per year RFP reduction requirement over 3 years (years
2002-2005) will be achieved. [An exception to this requirements is:
for severe areas with a design day value over 0.190 ppm, the period
of attainment is extended out to 2007]. The inventory includes
VOC and NOx emissions, and is based on allowable emissions
dictated by regulatory limits. Projections must be summarized for
intermediate years.
h) Modeling Inventory -- By November 15, 1994, the State must make
a demonstration that its plan provides for attainment by the
applicable date. To make the Attainment Demonstration, base year
and projected modeling inventories are needed since the CAAA
require that photochemical grid modeling or EPA-approved
alternative be used. The base year modeling inventory will be
derived from the 1990 base year inventory but must reflect
significant changes in conditions and activities of the episode days,
while the projected modeling inventory will have a 2005 (or 2007 for
areas over 0.190 ppm) base year. Both inventories will require
considerably more detailed data than either the 1990 base year or
the projected base year inventory. The projected modeling
inventory will be used to determine if the proposed SIP control
strategies are adequate to reach attainment by the designated date.
Extreme Areas:
a) Base Year Inventory -- Same requirements as Severe Areas
b) Emissions Statements -- Same requirements as Severe Areas
c) Periodic Inventory -- Same requirements as Severe Areas (base
years are 1993, 1996, 1999, 2002, 2005, 2008, and 2010)
d) RFP Projected Inventory for Year 6 (1996) - Same requirements as
Severe Areas
e) RFP Projected Inventory for Year 9 (1999) -- Same requirements as
Severe Areas
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f) RFP Projected Inventory for Year 12 (2002) -- Same requirements
as Severe Areas-
g) RFP Projected Inventory for Year 15 (2005) -- By November 15,
1994 the State must submit an inventory that projects how the 3
percent per year RFP reduction requirement over 3 years (years
2002-2005) will be achieved. The inventory includes VOC and NOx
emissions, and is based on allowable emissions dictated by
regulatory limits. Projections must be summarized for intermediate
years.
h) RFP Projected Inventory for Year 18 (2008) - By November 15,
1994 the State must submit an inventory that projects how the 3
percent per year RFP reduction requirement over 3 years (years
2005-2008) will be achieved. The inventory includes VOC and NOx
emissions, and is based on allowable emissions dictated by
regulatory limits. Projections must be summarized for intermediate
years.
i) RFP Projected Inventory for Year 20 (2010) -- By November 15,
1994 the State must submit an inventory that projects how the 3
percent per year RFP reduction requirement over years 2008 to
2010 will be achieved. The inventory includes VOC and NOx
emissions, and is based on allowable emissions dictated by
regulatory limits. Projections must be summarized for intermediate
years.
j) Modeling Inventory ~ By November 15, 1994, the State must make
a demonstration that its plan provides for attainment by the
applicable date. To make the Attainment Demonstration, base year
and projected modeling inventories are needed since the CAAA
require that photochemical grid modeling or EPA-approved
alternative be used. The base year modeling inventory will be
derived from the 1990 base year inventory but must reflect
significant changes in conditions and activities of the episode days,
while the projected modeling inventory will have a 2010 base year.
Both inventories will require considerably more detailed data than
either the 1990 base year or the projected base year inventory. The
projected modeling inventory will be used to determine if the
proposed SIP control strategies are adequate to reach attainment by
the designated date.
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CO Nonattainment Areas
Moderate Areas:
a) Base Year Inventory - Required by November 15, 1992, base year
is 1990, only pollutant inventoried is CO, represents actual emissions
on a peak 8-hour period basis in the CO season
b) Periodic Inventory -- A revised base year inventory is required to
be submitted no later than September 30, 1995, and every 3 years
thereafter until the area is redesignated to attainment, represents
actual emissions.
c) Modeling Inventory - Areas exceeding a design value of 12.7 must
submit an attainment demonstration plan by November 15, 1992
that demonstrates attainment by December 31, 1995. To make the
Attainment Demonstration, base year and projected modeling
inventories are needed. The level of inventory detail is dictated by
whether proportional rollback or gridded dispersion modeling is
required. The base year modeling inventory will have a base year
consistent with the CO season, while the projected modeling
inventory will have a 1995 base year. The projected modeling
inventory will be used to determine if the proposed SIP control
strategies are adequate to reach attainment by the designated date.
Serious Areas:
a) Base Year Inventory - Same requirements as Moderate Areas
b) Periodic Inventory - Same requirements as Moderate Areas
c) Modeling Inventory - Serious areas must submit an attainment
demonstration plan by November 15, 1992 that demonstrates
attainment by December 31, 2000. To make the Attainment
Demonstration, base year and projected modeling inventories are
needed. The level of inventory detail is dictated by whether
proportional rollback or gridded dispersion modeling is required.
The base year modeling inventory will have a base year consistent
with the CO season, while the projected modeling inventory will
have a 2000 base year. The projected modeling inventory will be
used to determine if the proposed SIP control strategies are
adequate to reach attainment by the designated date.
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3.0 IMPACT OF CAAA ON THE PROPOSED POST-1987
03/C0 POLICY AND GUIDANCE
The purpose of this section is to describe how the major emission inventory
elements of the proposed Post-1987 03/C0 Policy and the guidance materials issued to
support it (identified in Section 7.0) have been affected by the CAAA. The discussion
identifies the key inventory components of the previously proposed policy and describes
how they have or have not been changed by the CAAA. The impacts discussed here
principally apply to the development of the base year inventory.
3.1 Primary Pollutants of Interest
The poQotants of interest for ozone and CO base year inventories under
the CAAA remain unchanged from those examined imder the^roposed Post-19$7PoHcy.
For ozone Inyentortesv VOQ NOy and CO emissions from stationary pointand area, off-
highway mobile, and highway mobile sources are still required to tie inventoried. For
CO inventories, CO emissions from the same source types have to be investigated; :
Information concerning pollutants to be inventoried issued under the proposed Post-1987
Policy is still valid.
32 Source Types to be Inventoried
The types of sources to be included in base year inventories under the
CAAA are veiy similar to those found in the proposed Post-1987 Policy, with the
exception that biogenic emission sources have to be Included in the ozone inventories.
More details on the specific requirements for biogenic emissions are given in Section 4.0
on new inventory requirements. Excluding the biogenics requirement, ozone and CO
base year inventories are still required to address stationary point and area sources, off-
highway mobile sources, and highway mobile sources. The lists of VOC, NOr and CO
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point, area, and mobile source categories given in the previous Requirements Documents
(EPA 450/4-88-019 and EPA 450/4-88-020) are still valid as categories that, at a
minimum, must be addressed in the base year inventory. However, formats for reporting
1990 emission inventory data will differ from previous requirements. Information on
formats and systems for data reporting is contained in Section 4.8. States should also be
aware that EPA^s JointEmission Inventory Oversight Group (JEIOG)-I®'currently
conducting projects to identify missing or misciassifled source categories, particularly
for area sources; These projects will prodoce additional lists of source categories that
must be included in the base year inventoty. These source category lists will be included
in the area source guidance that EPA will issue in May 1991.
3 J Inventory Base Year
Under the CAAA, the base year for ozone and CO SIP inventories is 1990.
Under the proposed Post-1987 Policy, States receiving SIP calls in 1988 could use either
a 1987 or 1988 base year for their inventories, while States included in a second round of
SIP calls were allowed to prepare 1989 base year inventories. Many States have
compiled or begun compiling base year emission inventories under the old Policy using a
1987, 1988, or 1989 base year. These1inventories still have valioie^:-a^?^Wd:;not;:be
discarded or erased* For some areas, it may be possible, and allowed by EPA, to update
the 1987/1988/1989 inventories to a 1990 base year and submit them to fulfill the base
year inventory requirement under the CAAA. Details on updating 1987/1988/1989 base
year inventories to 1990 are provided in a separate discussion in Section 3.11.
Even if the 1987/1988/1989 inventories are not allowed to be updated, the
inventories can still be valuable tools from the standpoint of the inventory mechanisms
that have been established. These mechanisms include calculation algorithms that have
been set up, activity level data that have been collected, projection data that have been
collected, generic data ollection methods that have been established, and documentation
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procedures that have been established. These tools will be of great use in gathering and
developing the information required-for the 1990 base year inventories.
The 1987/1988/1989 inventories may also have a significant value in
connection with the performance of photochemical modeling (i.e., Urban Airshed)
validation runs for episodes prior to 1990. In order to validate Airshed modeling for the
1990 base year and beyond, modeling runs must be made using historical data. The
1987/1988/1989 inventories may be able to provide the emission rate and activity level
data needed to determine some of the modeling inventory emission rates. These
emission rates could be used to validate the model for observed ozone episodes
occurring in previous years, especially 1988. The extent to which these data will be
useful for model validation will vary from area to area, but nonetheless the 1987/1988/
1989 data should be maintained in some form. The mobile source data may be of
limited use since they would be based on an older version of MOBILE4.
3.4 Point Source Inventory Guidance
Theguidanceforinventoryingpointsoorcesof VOQNO^ and CO has
essentially not been changed from what was contained hi the previously issued guidance
lament Procedures for the Preparation of Emission Inventories for Precursors of
Ozone. Volume 1 (EPA 450/4«$$«O21, December 1388), For tills reason. States should
immediately begin data gathering for the development of tfie polnt source component of
their base year ly There is no reason to postpone data gathering and
development because no new guidance is planned for point sources that will significantly
affect State's 1990 base year inventory efforts. Some refinements and enhancements may
be issued to the previous guidance for selected source categories, but this information
will not affect the basic activity data that States need to be collecting on individual point
sources. States are encouraged to submit the polntsoorce portion of the Inventory to
EPA a$ early as January % 1992.
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As under the previously proposed Post-1987 Policy, EPA will specify a
point source emissions cutoff definition for VOC sources of 10 tons/yr. The point source
cutoffs for NOx and CO will remain at 100 tons/yr. While sources with emissions at
these levels and above must be inventoried as individual point sources, States are
encouraged to inventory sources below these cutoffs on an individual point source basis
as well. The only significant change is that for VOC sources is the 10 to 25 tons/yr
eiaissionsrange, 1990 base year inventwy emissions most be determined on an
individual: facility basis* Htcy cannot be extrapolated from the results of a survey of a
representative sample subset as mis allowed under the previons guidance.
States need to realize that these emission cutoff levels have been
specifically established by EPA for the purposes of ozone/CO base year SIP emission
inventories. These cutoff levels are, in several cases, not necessarily consistent with the
"major source" delineations given in the CAAA for VOC, NOr and CO sources. This is
because the two types of cutoffs are to be used for different purposes. In several cases,
the Act has established other major source cutoff definitions for purposes such as the
application of RACT, for new source review, and for Emissions Statements. For
example, for the purposes of Emissions Statements, NOx emission sources down to 25
tons/yr have to report emissions. In Serious CO nonattainment areas, major sources are
defined as those with the potential to emit 50 tons/yr CO. However, because these
other lower cutoffs exist, States should consider the benefits of going ahead and
inventorying sources, especially of NOx and CO, below 100 tons/yr if possible.
The most significant point source category guidance that EPA plans on
issuing for the 1990 base year Inventories deals with the overall category of waste
management practices; In the previous Procedures Document, EPA did not provide
extensive guidance on how to estimate emissions from waste management practices such
as hazardous waste treatment, storage, and disposal facilities (TSDFs), municipal solid
waste landfills, and publicly owned treatment works (POTWs) for wastewater. Since the
last guidance document, the Agency has been conducting extensive regulatory
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development programs for several of these categories and is now better equipped to
issue technical guidance on how VOC emissions are to be best estimated. Materials
available for this purpose are summarized below.
Estimating Emissions from Wastewater Treatment Plants and Hazardous
Waste Treatment. Storage. Disposal Facilities
In response to requests from State and local air pollution control agencies
involved in the preparation of volatile organic compound (VOC) and air toxics emissions
inventories, EPA's Control Technology Center together with the Emissions Inventory
Branch have developed the Surface Impoundment Modeling System (SIMS). Version 2.0
of SIMS was released in October 1990. SIMS is a personal computer software package
for estimating air emissions from surface impoundments and wastewater collection
devices. It can be used to estimate emissions from wastewater sources at hazardous
waste treatment, storage, and disposal facilities (TSDFs), publicly owned treatment works
(POTWs), industrial wastewater treatment facilities, and other similar operations.
SIMS contains models to estimate air emissions for the following types of
devices: diffused air surface impoundments, junction boxes, lift stations, mechanically
aerated surface impoundments, non-aerated surface impoundments, surface
impoundments with an oil film, sumps, and wiers. The emissions estimates of SIMS are
based on mass transfer models developed by the Emissions Standards Division (ESD) of
EPA during the evaluations of TSDFs and VOC emissions from industrial wastewater.
As a part of the TSDF project, a Lotus 123™ spreadsheet program called CHEMDAT7
was developed for estimating VOC emissions from wastewater land treatment systems,
open landfills, closed landfills, and waste storage piles, as well as various types of surface
impoundments. Contact Penny Lassiter at (919) 541-5396 or (FTS) 629-5396 for more
information. The air emission models for wastewater used in CHEMDAT7 have been
incorporated into SIMS. SIMS was developed to meet the needs of State and local
regulatory personnel who may not have information on the pollutant profile (flow rate
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and concentration) in the feed to wastewater treatment systems. SIMS can estimate a
default inlet pollutant profile for the water discharged from any of 29 industry types.
SIMS is designed for use on an IBM™ compatible personal computer. The
system is distributed on one 360 Kb diskette with a user's manual (EPA-450/4-90-019a)
and background information document (EPA-450/4-90-019b). Contact Mary Ann
Stewart at (919) 541-0875 or (FTS) 629-0875 for more information. To obtain copies of
SIMS or the accompanying documentation, State and local agencies should contact the
Control Technology Center at (919) 541-0800 or (FTS 629-0800).
Municipal solid waste landfill emission estimates can be modeled using the
Landfill Air Emissions Estimation Model developed by the Control Technology Center.
The system is distributed on a diskette (EPA-600/8-90-085B) with a user's guide
(EPA-600/8-90-085A). Contact the Control Technology Center at (919) 541-0800 or
(FTS) 629-0800 for more information.
States have reported difficulties with obtaining information on some of the
parameters required for the above models. States should be aware that some default
parameters are available and have been provided due to such problems. For multiple
wastestreams with incomplete information, a valid method involves running
representative wastestreams in the models. If more information is needed, contact State
and EPA Regional Office Resource Conservation and Recovery Act (RCRA) staff. They
should be able to provide information collected from facility permitting and from
implementation of the new RCRA Accelerated Rule on VOC Air Emissions at TSDFs.
Hazardous waste landfill estimates can also be made by sampling at large
commercial facilities. Useful sampling schemes, in order of priority, would be: samples
from collectors such as vents in a closed landfill cell; use of flex chambers at several
points across a landfill surface; and samples taken downwind of the landfill with back
calculation used to estimate emissions.
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Publications in the Air/Superfund National Technical Guidance Series
could be helpful in making emissions-estimates at hazardous waste landfills. There is a
four volume series collectively entitled Procedures for Conducting Air Pathway Analyses
for Superfund Applications. Volume I: Application of Air Pathway Analyses for
Superfund Applications (EPA-450/1-89-001, NTIS PB90 113374/AS) provides a general
discussion of air impacts and provisions for air pathway analysis, including emissions
estimates in conjunction with atmospheric dispersion modeling. Volume II: Estimation
of Baseline Air Emissions at Superfund Sites (EPA-450/l-89-002a, NTIS PB89
180053/AS) details the available methods for estimating air emissions prior to any
remedial action. Methods described include direct emission measurement techniques,
indirect measurements, and predictive emissions modeling. Suggestions are provided for
selecting from among the range of methods available given the associated range of costs
and uncertainties. Also available are Volume III: Estimation of Air Emissions from
Clean-up Activities at Superfund Sites (EPA-450/1-89-003, NTIS PB89 180061/AS) and
Volume IV: Procedures for Dispersion Modeling and Air Monitoring for Superfund Air
Pathway Analysis (EPA-450/1-89-004, NTIS PB90 113382/AS). These volumes are
available through the National Technical Information Service, 5285 Port Royal Road,
Springfield, Virginia 22161, phone (703) 487-4650.
3.5 Area Source and Mobile Source Inventory Guidance
In anticipation of the CAAA, EPA under the JEIOG program has been
conducting several research projects designed to develop new or improved methodologies
for determining emissions from a diverse group of stationary area source categories, off-
highway mobile sources, and highway mobile sources. The goal of these projects has
been to come up with better techniques for estimating emissions and activity levels used
for determining emissions. EPA will issue new guidance for several source categories by
May 1991. For stationary area source categories, there will be few new developments.
The new guidance is expected to primarily affect off-highway mobile categories such as
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airplanes and railroad trains, highway mobile source VMT determinations, and a few
area source categories.
For this reason, States may want to focus primarily on developing the 1990
base year inventory for point sources until the area and mobile source guidance
documents are issued. Until these documents are published, States should be working on
the data collection effort for area and mobile sources relating to activity data that are
historically important for a given source category. Even though some categories will
have revised methodologies presented, most will still need to have th ? basic activity level
data collected that have been important in the past. EPA will com- nicate to States in
technical memoranda developments in the new area and mobile so :e guidance as they
become available.
States should also be aware that for mobile sources, EPA will be issuing a
new version of the mobile source emissions model in 1991* l&s latest version, ait
updated MQB1LE4, is expected to be available la May. 1991. Most of the changes from
the current MOBILE4 are internal to the model such that the impacts on a State's use of
the model for compiling its 1990 base year and adjusted base year inventories will be
minimal. All nonattainment areas, except those in California, will be expected to use the
updated MOBILE4 model.
3.6 Maior Sources in the 25-Mile Boundary
lust as nnderthe proposed Post-1987 PoBcy, EPA will require under the
CAAA that 100 toa/jnr aitdgreater VOC,NO*ai»d CO cession sources, located within
25 miles at the designated nonattaimaent area, be included in the ami's 1990 base year
inventory This requirement is essentially unchanged from the previous policy. As
before, States need to use good judgement in deciding which 100 ton sources to include
in terms of sources near the edge but outside of the 25-mile boundary. Generally, all
100 ton sources within 25 miles of the nonattainment zone boundary must be included.
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Ones just outside of the 25-mile limit may also be included if the State feels they likely
contribute to the area's nonattainment problem for a variety of reasons (e.g., they have
very large emissions, they are influenced by prevailing winds, etc.). It is the responsibility
of the States to coordinate the exchange of inventory data for sources in the 25-mile
band that may cross State boundaries.
Sources do not have to be included in an area's 25-mile boundary if they
also fall into the specifically designated geographic boundaries of another nonattainment
area. EPA is preparing maps of the nonattainment areas and their 25-mile boundary
zones to show where overlaps occur. These maps will be distributed to the Regional
Offices and be available for State use in March 1991.
3.7 Temporal Basis of Emissions
The temporal bases on which emissions must expressed for 1990 base
year under the CAAA are the same as those used under the Post-1987 Policy.
For ozone inventories, VOC, NO^ and CO emissions must be determined and expressed
on an ozone season daily basis. The daily basis should reflect a typical weekday
operation during the peak ozone season months (usually June - August). For CO
nonattainment area inventories, emissions must be determined and expressed on the
basis of peak 8-hour period emissions during the season of maximum CO violations.
Peak CO violations usually occur during the wintertime months in most areas. States
can use other time periods for the CO season provided they can document that the
alternative period used represents the highest CO air quality period.
States are reminded that for the purpose of photochemical modeling,
temporal factors are also required to determine hourly profiles of emissions by category
for a summer weekday, Saturday, and/or Sunday.
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3.8
Rule Effectiveness
At this time, the requirements of the CAAA do not causeany changes in
EPA's previously issued requirements regarding theapplfcatfonof Role Effectiveness in
calculating base year emissions. The Rule Effectiveness guidance issued in connection
with the proposed Post-1987 Policy is still in force and is expected to remain so for the
purposes of the CAAA inventories. In addition to the Procedures Document referenced
earlier, States should also consult the EPA report Procedures for Estimating and
Applying Rule Effectiveness in Post-1987 Base Year Emission Inventories for Ozone and
Carbon Monoxide State Implementation Plans (published in June 1989) for detailed
guidance on how to incorporate Rule Effectiveness into their 1990 base year inventories.
3.9 Emissions Projections
Under the inventory requirements of the CAAA, as under the Post-1987
Policy, States have to prepare projected emission inventories (see Section 2.2). States,
therefore, will need to gather information relevant to making good emissions projections
several years into the future. It is likely that States will be sending out questionnaires to
industrial sources to solicit data on base year emissions and projected emissions before
all of EPA's CAAA projections guidance is issued in July 1991. Examples of the kinds
of questions States may want to use in questionnaires are listed below.
1. At what annual rate do you expect your business to grow or decline
in the next 5 to 10 years?
2. Do you anticipate changing any current process or throughput in the
next 5 to 10 years such that actual emissions of VOC, NO^ or CO
would change? If yes, explain.
3. Are process emissions expected to change in the next 5 to 10 years
because a rule or regulation has required a permanent change to
the operation, process, or equipment? If so, what changes?
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4. Are process emissions expected to decrease in the next 5 to 10 years
because of voluntary modifications to the equipment, process, or
operating hours? Is the reduction in emissions permanent? Is the
emission reduction required by a federally enforceable regulation or
is it voluntary?
5. Are process emissions expected to change in the next 5 to 10 years
due to seasonal or economic changes in facility activity? If yes,
explain.
6. Are emissions expected to change because a piece of equipment or
a process that was in operation in previous years will not operate in
the future? If yes, explain.
7. Are process emissions expected to change because of special
circumstances that are not anticipated to continue into subsequent
years (e.g., operation on a variance)? If yes, explain.
3.10 Quality Assurance Plans
The quality assurance (QA) provisions for inventories present in the
proposed Post-1987 Policy are still in force under the CAAA. States must design a QA
program and prepare a QA plan that is consistent with the previously issued guidance
documents: Guidance for the Preparation of Quality Assurance Plans for 0-,/CQ SIP
Emission Inventories (EPA 450/4-88-023) and Quality Assurance Program for Post-1987
Ozone and Carbon Monoxide State Implementation Plan Emission Inventories (EPA
450/4-89-004). States are reqoired to submit QA plans as an initial step ht tfceir
iBra^^ewlipeiit workaiul receive EPA approval on their plans early on In the
proesits. The QA plans must be submitted as a part of the State's Inventory Preparation
Plan (IPP) which is a new requirement for the 1990 base year inventories. The full
provisions and requirements of the IPPs are explained in Section 4.1. The content and
general form of QA plans must be consistent with the previously issued guidance.
As an aid to States in the preparation and checking of their inventories
prior to submittal to EPA, the Agency has been preparing a set of quality review
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guidelines. These guidelines will contain what is essentially a checklist of items that an
inventory must contain or address in "order for the inventory to be considered acceptable
for review by EPA. The guidelines will address whether inventories meet developed
specifications for completeness, consistency (both internal and with national trends),
reasonableness of emission values, and emissions documentation. EPA is projecting to
issue the final review guidelines in July 1991.
3.11 Updating Previous 1987/1988/1989 Base Year Inventories
Several ozone and CO nonattainment areas that received SIP calls in 1988
or 1989 have prepared or have begun preparation of base year emission inventories per
the requirements and guidance in the proposed Post-1987 03/C0 Policy (52 FR 45044,
November 24, 1987). These inventories have either 1987, 1988, or 1989 as their base
year. For the purposes of the CAAA, these inventories wilt h|ve to be either updated to
1990, the year of enactment of the CAAA, or redone totally to reflect a 1990 base year.
Only States which have ftilly completed portions of their base year inventories for 1987;
1988, or 1985* that they desire to update and have received EPA approval of these
portions wiii be considered for approval to update. Otherwise, agencies will have to
prepare a completely new inventory with, a 1990 baseyear. For the purposes of accuracy
and providing an inventory that will meet the goals of the CAAA, EPA encourages all
areas to prepare new 1990 base year inventories even if they did already assemble base
year inventories for 1987/1988/1989.
States should work with their respective EPA Regional offices to determine
if they can perform updates to 1987/1988/1989 inventories that may have been prepared,
and to determine how these updates should be performed. Regional office questions will
be resolved by EPA air headquarters staff [Office of Air Quality Planning and Standards
(OAQPS)]. Before any updating can be performed on 1987/1988/1989 inventories,
States will need to receive written authorization from EPA allowing them to do so. The
Regions will be able to provide this authorization. EPA will not accept any updated
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inventories in cases where this prior authorization is not received. For nonattainment
areas that meet the above stated conditions, States should request their EPA Regional
Office as soon as possible for the approval to perform an update if the State does not
desire to reconstruct a 1990 base year inventory from the start. In their petition, States
should clearly document the case for why they should be allowed to perform an update
of the 1987/1988/1989 inventory. Once approval to perform an update is received, the
State needs to prepare and submit an inventory preparation plan (IPP) as required by
EPA under the CAAA (see Section 4.1 for details on the IPP requirements). The IPP
must clearly specify all of the methods the State plans to use to accomplish the inventory
update. The IPP must also contain a QA plan for accomplishing the update and
ensuring the quality of the overall inventory.
For States that are able to perform updates to the 1987/1988/1989 base
year inventories, the updating process will likely be split alorig the lines of point, area,
off-highway mobile, and highway mobile sources. EPA plans to issue more direct formal
guidance for performing updates (e.g., specific growth factors to use on an individual
source category basis) in March 1991. However, for the purposes of this preliminary
guidance discussion, the following general guidance should be followed.
3.11.1 Point Sources
All stationary point sources of VOC, NOr or CO with emissions of 100
tons/yr or greater should be re-inventoried completely and not simply updated. Existing
point source guidance in the Procedures Document (EPA-450/4-88-021) should be used
to inventory the major sources. Sources with emissions less than 100 tons/yr can be
adjusted to the 1990 base year using scaling factors based on industrial growth for the
category generally or the plant specifically. The intended approach and source of the
growth factors should be fully explained in the IPP. Such an approach negates having to
reanalyze the whole plant. It also means that it is not required that smaller sources be
re-inventoried; however, States are encouraged to re-inventory these sources if feasible.
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An updated inventory of this type would give more accurate current emissions data than
could be obtained by adjusting older data with growth factors. Small VOC sources (i.e.,
emissions of 10 to 25 tons/yr) that were previously inventoried using sample surveys will
now have to be individually inventoried, whether for updating or for inventorying from
scratch.
In the one to three year span since the previous base year inventories were
compiled, it is possible that new point sources could have come into being that need to
be added to the 1990 base year inventory. Once new sources are identified, they should
be inventoried according to the existing guidance in the Procedures Document (EPA
450/4-88-021). For major sources, additions should be obvious and well known to the
State/local agencies. Similarly, major plant shutdowns or curtailments should be well
documented. Other methods that States may use to identify possible new sources or
identify source shutdowns include reviewing current industrial-directories, reviewing
recent permitting records for new plants and existing plant changes, and reviewing
nationally-oriented data bases such as the Toxic Release Inventory System (TRIS) for
SARA 313 reporting records. Again, the methodologies to be used should be specified
in the IPP.
In cases where no changes have occurred in the number of sources, States
will need to have a way to survey plants to determine if output has changed (positively or
negatively) such that emissions have been affected. This survey can be very simple and
general and needs to assess if any growth changes have taken place at the facility since
the original base year (1987, 1988, or 1989). The process of the survey could also be
used to determine growth expectations for future years that will be needed for the
various projection inventories required under the CAAA (see Section 2.2). The previous
base year emissions can be scaled up or down based on reported annual growth changes.
This methodology will be less resource intensive than gathering a complete new set of
inventory data, but more accurate than applying a single, industry-wide growth average
across all plants in a given source category.
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3.11.2 Area and Off-Highway Mobile Sources
Practically all of the emission estimates for area and off-highway mobile
sources are based on the use of an emission factor and some activity/commodity level(s)
(e.g., population, employment, equipment counts, etc.) that is a surrogate indicator of
emissions. States should perform updates for these source types by examining how the
surrogate activity levels have changed over the period to 1990. For most of the source
categories, changes over the one to three year span will not have been large. For each
area and off-highway mobile source category, States need to investigate the key emissions
surrogate parameters and determine how they have changed since the previous base year
inventories were developed. The Procedures Documents (EPA 450/4-88-021 and EPA
450/4-8l-026d, revised) should be reviewed to determine what the key surrogates are.
They will generally be expressed in the emission factor itself (e.g., lbs VOC/caciia) or in
a multi-step calculation process (e.g., pieces of equipment x hours of operation per piece
x lbs VOC/hr of operation). In some cases, the extrapolation to 1990 will be very easy
to perform because the surrogate statistics are readily available (e.g., population). In
other cases, the State will have to determine new data that are very site-specific (e.g.,
airplane takeoff/landing cycles at an airport) to the point that the category is actually
being re-done as opposed to being updated.
States are reminded that EPA will be issuing new inventory guidance for
some area and off-highway mobile source categories in May 1991 that may significantly
affect how emissions are to be determined. For these categories (railroads, aircraft,
solvent uses), it will likely not be possible to perform updates from the previous
estimates. Instead, new emission estimates will have to be prepared using the new
methodology.
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3.11 J Highway Mobile Sources
Highway mobile source emission estimates must be derived from scratch
using a 1990 base year for ail areas, iitdudiiig those with 1987/1988/1989 base year
Inventories that were allowed to update their overall inventory. Areas with approved
highway mobile source inventories for 1987,1988, or 1989 must stfll develop new 1990
base year inventories; There are several reasons EPA is adopting this position. One
relates to the way that mobile source models calculate emission factors. Relatively
significant changes occur in the factors with fleet turnover from one model year to the
next. Also, with new road construction, VMT patterns change that significantly impact
mobile source emissions. These changes may involve not only more roads, but also
changes in speeds both higher and lower. For example, in 1990, several interstate roads
now have 65 mile per hour speed limits instead of 55. Since the highway mobile source
component of these inventories is almost always the major contributor to total area
emissions, it makes sense to reevaluate its emissions from year to year. The planned
release of a new version of the mobile source emissions estimation model, MOBILE4.1,
in May 1991 also provides additional justification for totally reevaluating mobile source
emissions as opposed to trying to update them. [California can continue using the
EMFAC mobile model.] The planned May 1991 release of new guidance for
determining VMT further solidifies the need for States to re-calculate highway mobile
source emissions for the purposes of the 1990 base year inventories under the CAAA.
States should wait until the updated version of MOBILE4 and VMT development
guidance is issued in May 1991 to begin construction of their 1990 highway mobile
source inventories. However, State air agency staff should begin contacting Metropolitan
Planning Office (MPO) personnel (or their equivalent) to become familiar with the
MPO's VMT estimation methods, base years of data, and overall capabilities, and to
explain to the MPO's the CAAA provisions.
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4.0 NEW INVENTORY REQUIREMENTS UNDER THE CAAA
This section of the discussion focuses on the new features and
requirements of the CAAA that are associated with emissions estimation and emission
inventory development. Included here are discussions on inventory preparation plans
(IPPs), Emissions Statements, biogenic emissions, emissions "backcasting," substitution of
NOx emission reductions for required VOC reductions, use of a new, updated MOBILE4
model, and written and computerized inventory data reporting. These discussions should
be viewed as preliminary descriptions of the new features. EPA will issue more detailed
guidance on Emissions Statements, the use of the updated MOBILE4, the estimation of
biogenic emissions, and computerized inventory data reporting in the spring of 1991.
4.1 Inventory Preparation Plans
Under the previously proposed Post-1987 03/CO Policy, States were not
required to tell EPA how they planned to prepare, document, and submit their base year
emission inventories prior to the actual submittal of the materials. For the purposes of
the CAAA and its emission inventory requirements, EPA is adopting a new approach.
For CAAA base year inventories, EPA Is requiring that States prepare an Inventory
Preparation Plan (IPP) that is brief but that specifies to EPA how they intend to
develop, docnment, andsobnilt their inventories. The basic point of having the plans
will be to give States the chance to tell EPA upfront how they plan to compile the
required inventories and allow for EPA feedback in an effort to avoid States using
approaches that are not consistent with EPA requirements. With the use of IPPs, EPA
can help guide the preparation of inventories and hopefully produce emission estimates
that are of higher quality and that are consistent with the CAAA requirements. IPPs are
due in final form by October 1, 1991.
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States should submit their IPPs to their respective EPA Regional Office
(RO) for review, and EPA headquarters (OAQPS) should also be copied on the
documents and any correspondence relating to the plans. EPA headquarters copies
should be sent to: Chief, Inventory Guidance and Evaluation Section, Emission
Inventory Branch (MD-14), Technical Support Division, U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina, 27711.
States will need to prepare an IPP for each specific nonattainment area
where base year inventories are required by the CAAA to the extent that different
approaches will be used. If a State has multiple nonattainment areas but plans to use
the same overall approach for each, the State can submit a single IPP that details that
approach and the areas to which it will apply. States need to be aware that EPA yrill not
accept a base year inventoiy for review from a State until EPA bas received, renewed,
and approved of an IPP for that inventoiy. EPA approval of an IPP does not, however,
signify that EPA unconditionally accepts all of the information to be contained in the
actual inventory. The inventory will be reviewed separately and on its own merits
regardless of how well or how poorly the IPP was assembled. In approving the IPPs
submitted, EPA will be saying we accept your intended approach for inventory
compilation. The results produced by these approved approaches will have to undergo a
separate review and approval process.
An IPP should address how a State plans to inventory all sources
(regardless of size) of the ozone pollutants (VOC, NO,,, CO) or CO for CO
nonattainment areas. Separate discussions should be used to address stationary point,
stationary area, off-highway mobile, highway mobile sources, and biogenics. The overall
basis for a State's inventory needs to be communicated in the IPP. If an inventory
started under other programs will be utilized (e.g., under the proposed Post-1987 Policy),
this should be stated. Generally, the State's starting point for the base year inventory
effort should be summarized.
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For point sources, States need to define how all pertinent emission sources
will be identified and located. The plans need to tell EPA how point source activity
levels and associated parameters will be developed, and how these data will be used to
calculate emission estimates. States can describe any source surveys that are planned,
and if they intend on using existing data contained in systems such as NEDS, AIRS, EIS,
or State permitting files. The extent to which a State plans to use EPA's AIRS and PC-
SAMS data base management systems to compile their point source inventory should be
explained.
For stationary area and off-highway mobile sources, the plan needs to
explicitly state what source categories will be addressed and which will not because they
do not occur in the nonattainment area. For those categories to be included, the plan
should indicate what calculational method will be used to determine emissions. If a
State plans on just following the guidance in the existing Procedures Document for all
categories, they should simply report that they will be applying the EPA-recommended
approaches. If the existing EPA guidance has alternative methods for a category, the
IPP should clearly indicate which one the State intends to apply for its inventory.
Particular emphasis should be given to categories in which the State plans to use an
approach other than that recommended in the previous guidance document (i.e., the
Procedures Document). Any major assumptions that will be used that would be key to
the development of emission estimates in a category should be clearly stated.
For highway mobile sources, the IPP should provide a clear indication of
how the State intends to develop VMT estimates and mobile source emission factors.
Any predictive models that will be applied should be identified and key assumptions in
the use of the models should be stated. Other items that should be addressed include
specifications of the vehicle classes that will be covered, the fuel RVP level to be used,
ambient temperatures to be used, I/M and anti-tampering programs that are in place,
and a specification of whether or not vehicle refueling losses are being covered by the
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mobile source model estimates or they are being calculated separately as an area source.
The control effectiveness the State used for adopted Stage II controls should be stated.
The IPP needs to clearly describe how the State plans to present and
document the inventory to EPA. The general kinds of documentation that will be
provided and the form of this documentation should be described to the extent that EPA
can judge if it would be satisfactory for inventory review purposes. The IPP should
specify the written and computerized ways that a State plans to compile and submit its
data. States must clearly delineate how State data base/data systems are to be used and
how EPA systems such as AIRS, AFS, etc. are to be used. EPA believes that going
through this exercise will help a State better and more efficiently plan how its inventory
can be assembled.
One componenl that must be contained in an i£P is the QA plan for the
invrotoryl This plan would describe the overall QA program that the State intends to
use during the compilation of the inventory. The QA plan should be constructed
according to the guidance provided in Section 3.10 of this discussion. Having the QA
plan in the IPP is a very logical organization. The IPP will describe how the inventory is
to be created and presented, and the QA plan represents a vital link to the successful
and accurate development of good inventory information. Putting the QA plan in the
IPP reinforces the idea that QA is an important and necessary part of the inventory
development process.
Generally, EPA envisions that the IPPs will be brief. It is EPA's intent
that they be concise and to the point, and only provide as much detail as is necessary to
communicate to the Agency how the State intends to develop and present its inventory.
However, the document needs to contain sufficient information to enable EPA to make
a judgment that the intended State inventory approach is sound. Although no specific
IPP format is required, the discussion should probably include the topics listed below at
a minimum.
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Suggested IPP Topics
A. Introduction
- define what nonattainment area the plan is for, whether attainment for 03,
CO, or both, classification(s) of the area.
- background/basis for the inventory (i.e., previous efforts that are viable and
related), starting point
- define how the plan is structured, what does it contain
- specify who is responsible for the inventory and who is actually compiling it
(air agency, consultants, etc.)
B. Point Sources Approach
- how will sources be identified and located
- how will minor sources be identified
- define role of existing NEDS, AIRS, NAPAP, permitting data
- identify data collection methods to be used (e.g., surveys, etc.)
- basis for activity level data and emission estimates
- basis for control efficiencies
- application of rule effectiveness
- basis for rule penetration and rule effectiveness levels
C. Area and Off-Highway Mobile Sources Approach
- what categories will be addressed and why
- what categories will be excluded and why
- what estimation methods will be used (e.g., AP-42, Procedures Document,
site-specific surveys, etc.)
- methods for collecting activity/commodity level data
- application of rule effectiveness
• basis for rule penetration and rule effectiveness levels
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D. Highway Mobile Sources Approach
- specification of how VMT are to be determined
- specification of the mobile source emissions model used (will be an
updated version of MOBILE4 for every State except California)
- specification of key assumptions for the emissions model involving
parameters such as temperature, speeds, existence of I/M and anti-
tampering programs, incorporation of vehicle refueling losses, etc.
E. Documentation Approach
- written presentation and documentation
- computerized compilations and documentation
- use of AIRS online, or PC-SAMS and PC-AMS
- submission of data in AIRS-compatible format
F. Quality Assurance Plan
- description of QA program
- how QA program will affect and benefit inventory
- description of adherence to previously issued QA guidance
42 Emissions Statements
EntfesfoBSiStatanestereprese^pcttm States
under the CAAA [Section 192 (a)<3)(B)]» Emissions Statements are required to be
submitted in ozone nonattshtment areas for all sources of VOC and NOx emissions-
Sources emitting less than 25 tons/yr of VOC or NOx may be able to obtain a waiver
from the Emissions Statements requirement if the State includes such sources in their
emission inventory updates and determines emissions in a manner acceptable to EPA
[Section 182 (a)(3)(B)(ii)]. So&rceswftlieiiiissiOBSOf eitherpollntaat thatare equalto
or greater than 25 tons/yr havetosobmit an Emissions Statement underall conditions.
The statements have to specify actual source emissions and contain a certification by the
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source that the information is accurate to the best of their knowledge. Emissions
Statements are first due to EPA in 1993 or three years after enactment of the CAAA.
Thereafter, annual updates are required to be submitted. The Emissions Statement
Requirements apply to all five ozone nonattainment area classifications.
EPA wants the system of Emissions Statements that States implement to
be consistent across the country. The Ozone/Carbon Monoxide Programs Branch of
OAQPS is currently formulating Agency policy and guidance on how the Emissions
Statements requirements are to be implemented. This guidance will describe the kinds
of statements that are needed and how these statements will interface (and potentially
overlap) with the emission inventory requirements already imposed by the CAAA. The
guidance will be structured around providing a standardized format for Emissions
Statements and telling States how the values reported in the statements should mesh
with their inventories.
Once all Emissions Statement specifications and requirements are
complete, States will need to communicate these specs to their respective emissions
sources. States will also need to have a system in place that is capable of tracking when
new sources come on line that become subject to Emissions Statement requirements and
when others are no longer in operation and do not need to submit statements. States
will need to have a system in place to process and compile Emissions Statements and
report the data to EPA as specified in final guidance. At the current time, EPA is
planning on issuing final guidance for States on Emissions Statements in May 1991.
4.3 Biogenic Emissions Estimates
Under the CAM base year emission inyentoiy requirements for ozone
nonattainment areas, Stales will to prepare an4 ssln&it emission estimates for
biogenic emissions* Biogenicemissioas estimates arerajoired tbr marginal, moderate,
seiiotis,9evej^andextremearea& EPA plans to supply States with the means to
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estimate biogenic emissions. The Agency has developed a model for estimating biogenic
releases known as BEIS (Biogenic Emission Inventory System). EPA will provide the
model to States in a PC version along with instructional guidance on its use. States will
be able to run the model by basically loading it with a host of meteorological data that
should be readily available for all locations. More information and guidance on the use
of BEIS will be issued in the spring of 1991. The computer program, PC-BEIS, is also
expected to be distributed on an EPA bulletin board at the same time as the guidance is
issued.
States are strongly encouraged to use the EPA model to estimate their
biogenic emissions but they are not required to do so. If States plan on using an
alternative approach to estimate biogenic emissions, this approach needs to be described
in detail in the State's IPP for the nonattainment area and EPA approval granted before
the approach is implemented. As with the overall IPP, approval of the basic alternative
inventory approach for biogenics does for automatically guarantee EPA acceptance of
the estimates in the submitted inventory. They will still be subject to review and
comment by the Agency.
4.4 Emissions "Backcasting"
EPA currently has underway a number of research activities to determine
better methods and information resources for estimating ozone precursor emissions. The
efforts are generally concentrated on stationary area, highway mobile, and off-highway
mobile emission sources. To varying extents and over varying timeframes, these research
efforts are expected to produce results that will impact the way that EPA will require
that base year emission inventories be developed. New emission factors and emission
estimating models may become available that need to be applied to the base year
situation. be called aj^ to Tjadccast" (as
contrasted^ forecasting) their base year "'emission* significantly
Improved estlm&tiitgimertK^ Since the base year inventory is the
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basis for all other CAAA inventories, changes to the base year inventory have the
potential to affect all other required inventories, and an area's required emission
reductions and ultimate attainment demonstration.
EPA does not anticipate that backcasting will be routinely required to an
extensive degree. Needed revisions will likely be infrequent and limited to a source
category or two each time. One reason for informing the States of the potential need for
this activity is to reinforce the idea that States need to document well how all emission
estimates are prepared and that they need to keep good records of the inventory data
and the information that supports them.
4.5 Use of NO, Reductions to Substitute for VOC Reduction Requirements
Under the CAAA, Moderate ozone nonattainment areas and above are
required to demonstrate a 15 percent reduction in VOC emissions from base year levels
by 1996 [Section 182 (b)(1)(A)]. After 1996, Serious and above areas not in attainment
must demonstrate that a 3 percent per year reduction is being achieved to validate that
reasonable progress is being made towards attainment. Is certain situations, the Act
does allow the substitution of NOx emission redactions for required VOC redactions.
For Moderate areas and above, NOx rednctions canbe credited towards
the 15 percent VOC reduction requirement, but only after the first six years after
enactmenti^Mt, after 1996) [Section 182 (b)(1)(A)]. For Serious, Severe, and Extreme
areas, NOx reductions can be substituted for annual VOC reduction tracking
requirements after 1996 [Section 182 (c)(2)(C)]. To qualify for the substitution, a State
must make a demonstration to EPA that the combination of NOx and VOC reductions is
at least as effective as VOC reductions alone.
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4.6
Release and Required Use of Undated MOBILE4 Model
In May of 1991, EPA plaits to issue an updated version of its mobile
source emissions estimation model known as MOBILE4. The updated version of
MOBILE4 will replace and supersede its predecessor* States, with the exception of
California* are required to use the updated version in determining highway mobile
source emissions for all of their base year emission inventories; California can continue
using the EMFAC mobile model. The overall application of the updated MOBILE4 for
base year inventory purposes is generally the same as that used for the previously issued
version of MOBILE4. The majority of the enhancements in the revised model are
internal to the model and do not directly impact the user for base year inventory
emission factor generation purposes. Specific guidance on the scope of the model
changes and their impacts, and on the use of the model for base year inventories will be
issued in May 1991.
4.7 Written Inventory Reporting and Documentation Requirements
Base year emission inventory information under the CAAA will have to be
provided to EPA in both written and computerized formats. The written presentation
has to contain documentation that is extensive enough for the Agency to reproduce the
emission estimates that are submitted in the inventory. Written reporting/documentation
requirements are summarized in this section. Computerized submittals of emissions data
and documentation will have to meet the specifications set forth by EPA's National Air
Data Branch (NADB). The parallel specifications for computerized submittals are
presented in Section 4.8.
Under the CAAA, EPA is goingto require |hfit States prepare written
inventory documentation reports according to a more standardized set of guidelines
than were issued previously. Inventory reports that are sot prepared according to the
guidelines will be harder for EPA to review and more likely to be deemed unacceptable
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by the Agency. This does not mean .that every inventory report will have to be organized
precisely the same and look identical." EPA's primary interest is that all inventories
address the crucial elements inherent in a good inventory and provide summary data and
documentation that allow the quality of the inventory effort to be effectively judged.
Therefore, the emphasis is really on the types of data that need to be reported and not
the specific format they are reported in. Invmtories sot meeting the minimum data
reporting and standardsestsbll£h^& However, be
deemedunacceptable and retained to the States for modification before any further
technical quality reviewwill be performed.
EPA has alneacly published a detailed guidance document on this issue
that States need to consult before preparing their written reports. This document is
entitled Example Emissions Inventory Documentation for Post-1987 Ozone State
Implementation Plans fEPA 450/4^9-018^. If a State does not have the report, copies
can be obtained from the Emission Inventory Branch of OAQPS. As the title implies,
the guidance document provides a complete example of how an inventory should be
compiled and documented. The kinds of summary tables and graphics that States need
to provide to EPA for their base year inventories are clearly shown. The examples cover
point, area, and mobile sources, and they address quality assurance aspects of the
inventory. Even though the guidance was prepared for ozone inventories, the examples
are equally applicable and transferable to CO inventories. It also provides States
guidance on how to summarize quality assurance activities that need to be carried out in
the compilation of the inventory.
EPA's recommended outline for the organization and content of a State's
in^t^:r«po!t & The combination of the Table 1 outline with the
Example Emissions Inventory Documentation report should provide States with all of the
guidance necessary to prepare an inventory documentation report that will satisfy EPA
and the intent of the CAAA.
45
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The introduction to an. inventory report needs to contain a description of
the nonattainment area that has been inventoried; a listing of the counties covered; a
map of the area including the 25-mile boundary outside of the nonattainment area; an
identification of who prepared the inventory and who are the respective contacts for
major inventory components; a description of major inventory problems or deficiencies;
and a discussion of how the remainder of the report is organized. After the introduction,
the report needs to contain a thorough summary of the emissions data by pollutant,
source type (point, area, mobile), and geographic area. The Example Emissions
Inventory Documentation report provides several examples of tables and graphics that
can be presented for point, area, and mobile sources. At a minimum, the report needs
to include summary emissions tables by pollutant and by source type; summary emissions
tables by county; and graphics illustrating the contribution to areawide emissions by
source type. States are required to report emissions data both on an annual and
ozone/CO season daily/8-hour basis.
Separate discussions need to be presented to describe inventory
development procedures and results for point, area (including off-highway mobile), and
highway mobile sources. In addition to the specific parameters germane to point, area,
and mobile source types, each source type discussion needs to explain how emissions
were temporally allocated to a daily basis and how rule effectiveness was incorporated
into each emission estimate.
The point source discussion needs to include a description of how the list
of sources to be inventoried was identified. The discussion needs to address the issue of
completeness of source coverage (i.e., how did you ensure that all 10 ton/yr sources were
identified). Data collection methods and tools should be thoroughly explained and
documented. All information surveys that may have been conducted need to be
discussed and the results provided (probably in an appendix). All sources inventoried
should be listed according to their source category type (e.g., refinery, graphic arts,
46
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TABLE 1. OUTLINE FOR EPA RECOMMENDED FORMAT/CONTENTS FOR
OZONE/CO SIP EMISSION INVENTORY REPORTS
I. Cover and Title Page
A. Title (geographic area, type of inventories, pollutants, base year)
B. Responsible agency [e.g., NC Dept of Health and Natural
Resources]
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
[For example, In response to letter from to , dated
requesting preparation of a SIP for demonstration of attainment of
ozone NAAQS in (geographic area\ beginning with an emission
inventory for base year 1990. Base year emission inventory serves as
the basis for emissions modeling and projections for future years.]
B. Geographic area covered, base year, type of inventory (03 SIP, CO
SIP), pollutants included (VOC, NO,,, CO)
C. Brief discussion of contents of report
[Note: Include a paragraph or less describing each major report
section. For example, Section 2 summarizes stationary point, area
and mobile source emissions by county. Section 3 describes
stationary point source emissions and includes a discussion of
methods used to gather data, calculate annual and seasonal
emissions, and presents a summary of emissions by plant. Detailed
point source emissions data are presented in Appendix F. Section 4
discusses...]
47
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D. Discussion of automated data systems used (SAMS, AIR AFS,
AMS-PC, State system)
E. Major problems, deficiencies, portions of inventory not included
F. List of primary guidance documents and references used (EPA
guidance 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
(point, area, mobile - broken down by nonhighway sources and
highway vehicles; brief discussion in footnote, etc. to clarify what
each includes - point sources above cutoff, area sources excluding
nonhighway mobile sources?, nonhighway sources include aircraft,
trains,...)
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. detailed data for each plant (can put in appendix instead)
5. point source emissions summary
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
48
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C. Mobile Source Emissions
1. Non-highway Mobile Sources
a. same information as for stationary area sources
2. Highway Vehicles
a.
mobile model inputs and outputs
b.
VMT estimates
c.
emission estimates
d.
documentation (can put all or part in Appendices)
e.
mobile source emissions summary
f.
discussion of procedures and methodologies
VI. Quality Assurance/Quality Checking (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
VII. Appendices
A. Lengthy data, calculations, documentation of methodologies/models
Notes: Both annual and seasonal emissions (03 - summertime daily emissions, CO - CO
season 8-hour maximum emissions) should be presented in the summary and sections
describing emissions.
All pages in the report (including appendices) should be numbered. Sources of
information should be referenced throughout. Include complete list(s) of references
within body of report (preferably at end of each section).
Margins of report should be adequate so that copying of report will not lose text, page
numbers, or other important information.
In addition to hard copy reporting requirements for emissions data, data must be
reported in a computerized AIRS compatible format (Section 4.8). To the extent that
data have been successfully loaded onto AIRS and reports can be generated from
AIRS for nonattainment areas, this may alleviate transmittal of portions of the hard
copy inventory that contain the detailed emissions data.
49
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SOCMI plant, etc.). The methodology by which activity levels and emissions were
determined for each plant or source category (when applicable) needs to be succinctly
but explicitly explained. Large volumes of detailed data should be put into appendices
but clearly linked to the text discussion in terms of how they were used to determine
emissions. Summary tables and graphics should be prepared to address just point source
emissions (e.g., summary table on VOC point source emissions ranked by source category
type).
The area source discussion should cover stationary area sources, with
off-highway mobile sources included in the mobile source discussion. The report needs
to state if any source categories were not considered in the inventory and why. All of
the source categories covered should be listed and the method used to determine
emissions identified. If the EPA-recommended approach in the Procedures Document
was used, but a different emission factor was used, this needs to be noted. For all
approaches used (EPA or otherwise), the derivation of activity/commodity level data
needs to be thoroughly discussed. As needed, supporting data can be put into
appendices but the appendices have to be fully explained and clearly linkable back to the
text discussion and emission estimates. Like point sources, emission summaries should
be developed for area sources. The summaries need to reflect emissions by county and
for the entire nonattainment area. Examples for these types of sources are found in the
Example Emission Inventory Documentation report.
In the mobile sources section of the inventory report, States need to clearly
describe how off-highway mobile emissions were calculated, how highway vehicle
emission factors were determined, and how VMT estimates were determined. For
highway vehicle emission factors, the States need to fully report how they used the
updated MOBILE4 to help determine emissions. The values used for all input
parameters required by the model should be presented and their basis discussed. The
emission factors produced by the model should be presented by vehicle class. For VMT,
the State needs to describe the methodology employed to generate VMT data, key
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assumptions and inputs to the process, and the group responsible for the estimates. The
VMT data determined should be presented by road type classification and by vehicle
class. States need to explicitly describe the derivation of VMT. It is not acceptable to
simply state that the Department of Transportation ran a transportation planning model
and provided the air agency with VMT numbers. Simply providing a computer printout
of a transportation modeling run, without any explanation, is also not acceptable. The
agency that is responsible for the overall inventory must ensure that sufficient
documentation is provided to fully explain how VMT and mobile source emission factors
were derived.
The report needs to fully describe how the VMT data were combined with
the emission factors to produce mobile source emission estimates. The calculated
estimates need to be provided in summary form by vehicle class, by pollutant, and by
county. Simple examples of how these summaries can be provided are given in the
Example Emissions Inventory Documentation report referenced previously.
The inventory report needs to have a separate section that describes the
implementation of the State's QA plan and the results achieved by the QA program.
For all source category types, the QA discussion should address the completeness of the
inventory (e.g., are all of the EPA-recommended area source categories accounted for),
reasonableness of the emission estimates (e.g., are estimates for a category consistent
with some other related parameter for the area), and relative accuracy of the data (e.g.,
do all of the individual county emission figures total to the sums given for the whole
area). The QA discussion needs to show the range of quality review that was performed
and how this review benefitted the inventory. The Emission Inventory Branch will be
issuing additional quality review guidance in July 1991 to help States perform many of
these quality checks and provide the kinds of QA feedback deemed necessary by EPA.
51
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4.8
Computerized Data Management and Reporting
The Aerometric Information Retrieval System (AIRS) will be the official
repository for the SIP emission inventory data. EPA will provide PC software packages
for States to perform preliminary inventory preparation activities; trowever, all SIP data
must be successfully updated to AIRS before final approval of theSEP inventory is
given. All SIP inventoiy data submitted to EPA. must be in an AIRS-compatible format
in order for It to be acceptable Point source data transfer from the SAMS PC package
to the AIRS Facility Subsystem (AFS) will begin in January 1992. Area Source data
transfer from the new area and mobile source PC package to the AIRS Area and Mobile
Source Subsystem (AMS) will begin in May 1992. States' ability to use AFS and AMS
directly for their submittals is discussed further below.
If States do not update SIP data directly to AIRS, EPA Regional Offices
will perform the updates and provide the States with printed reports. States will review
these reports and correct any errors before final EPA confirmation of inventory
completeness is given.
States are advised to establish internal coordination to eliminate any
conflict between submittals of their point source SIP data and their annual "NEDS" (for
the former National Emissions Data System) data. NEDS point source data submittals
are currently updated to AFS. The SIP data, when updated to AFS, will share some
common data elements with the regular NEDS data previously submitted. Effective
internal coordination by the States will assure that common 1990 data reported for
specific sources to meet SIP and NEDS requirements are the same within the AFS data
base.
A significant degree of quality assurance will be prevalent in point source
and area source PC and mainframe software products. A wide range of data validation
will be performed to ensure an appropriate response to inventory requirements and
52
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EPA's ability to load States' data to- AFS and AMS. Data validation, error correction
and re-submittal procedures will be supplied to the States in the near future.
SIP data generated on PCs should be submitted to the appropriate RO
contact. The ROs will perform the preliminary review of State submittals. Once the RO
review is completed, SIP data will be further reviewed by the Emissions Inventory
Branch (EIB) for completeness. The States might be contacted by EIB and the RO to
perform some additional adjustments to their SIP data submittals. While the State
submittals can be EPA certified as complete, data problems could arise when attempting
to load SIP data to the national mainframe data bases. If this occurs, EIB, the RO, and
the National Air Data Branch (NADB) will work with the States to resolve data
problems.
NADB is responsible for the provision of AIRS and related software
systems and procedures for States to prepare and submit their point source and area and
mobile source inventories. Various submittal mechanisms will be available for the States
to fulfill their inventory requirements. The information below addresses inventory data
management issues for point, area, and mobile sources.
4.8.1 Point Source Inventory
States submitting point source inventories can choose one of four basic
options to submit their data:
Option
When Available
(1)
Current SAMS Version 3.11
Now
(2)
SAMS Version 4.02
March 28, 1991
(3)
AFS Batch Transaction
Format Available3
May 17, 1991
53
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(4) Interactive direct entry
to AFS
December 31, 1991
NOTES: (1) SAMS Version 3.1 (used for the Post-87 SIP inventories).
(2) SAMS Version 4.0 will include additional data elements (Stack-
ID and Segment-ID) and edits to ensure compatibility with AFS.
A later version of SAMS, Version 4.1, will include the capability
to generate an AFS formatted transaction file (available mid-July
1991).
(3) This format must be used by States submitting data electronically
from their own computer system directly to EPA's mainframe.
Option (1)
States could begin work to update their inventories to 1990 immediately
after receiving this guidance document by using SAMS Version 3.1. However, prior to
uploading to AFS, reconciliation of SAMS 3.1 data with the AFS data structure at the
stack and segment levels of related SAMS/AFS facilities will be required. SAMS
Version 4.0 will allow entering this additional information thereby reducing to a
minimum the data conversion process from SAMS to AFS. Information relative to the
required data elements for the inventory is also provided in this guidance document.
If you plan to use SAMS Version 3.1, please contact John Ackermann of
NADB at (919) 541-5687 (FTS 629-5687) to discuss the data reconciliation process and
issues.
Option (2)
SAMS Version 4.0 can be installed on a PC so that it can be used to
update a SAMS data base prepared with an earlier version. By using the new data
elements and AFS-edit routine in Version 4.0, the SAMS user can prepare 1990 SIP data
54
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on SAMS (PC) that will be consistent with their State's files on AFS (mainframe). The
Technical Support Division (TSD) wttl assist State and local agencies with data output
from AFS, to update detailed point source data in SAMS. Then the SAMS data can be
transferred to EPA's mainframe AFS data base with a minimum of corrections.
There will be a later release of SAMS Version 4.1, available in mid-July
1991. This newer version will provide a capability to generate AFS-acceptable
transactions as an output from SAMS. The AFS-formatted transaction data from SAMS
will be uploaded to the EPA IBM mainframe and then updated to AFS. TSD will
review the submitted inventory prior to updating the AFS files. The updating of AFS
will begin in January 1992.
Option (3)
States submitting an AFS formatted transaction file to EPA (format
definitions will be provided in May 1991) can either mail a magnetic non-labeled tape or
transmit a data set (if State has appropriate connectivity and technical resources) to the
National Computer Center. Tape submitted data should be structured in IBM extended
binary coded decimal interchange code (EBCDIC). The loading of the transaction files
to AFS will begin in January 1992. Contact Jerry Husketh of NADB at (919) 541-5449
(FTS 629-5449) for more information.
Option (4)
In the long-term, the preferred option is to enter the SIP inventory point
source data directly into AFS. However, this option will not be available to users until
January 1992. Contact John Ackermann at (919) 541-5687 (FTS 629-5687) or Jerry
Husketh at (919) 541-5449 (FTS 629-5449), Technical Support Division, if you plan to
use this approach.
55
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Point Source Data Elements
Applicable data elements that will be supported by AFS are as follows.
Data elements required for the 03/C0 SIP inventories are shaded. These data elements
will be more explicitly defined in the 03/C0 SIP Inventory Requirements Document
guidance to be issued in March 1991.
List of Data Elements for Plant General Level:
Description
~~F1PS state code
**FIPS county code
•year of record for emissions
~•plant ID from AFS (or NEDS)
~plant name
•street address
~city same1
~zip code
local plant ID
~FIPS city code1
~plant latitude2
~plant longitude2
~UTM rone2
~UTM easting2
~HTM northing2
township/modeling grid
f||S
secondary SIC code
tertiary SIC code
principal product
number of employees
plant area
plant contact
contact telephone number
nil Pint
plant comment
56
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Required for 03/C0 SIP.emission inventories.
* Mandatory for AFS format, for Adds.
** Mandatory for both Adds and Changes to AFS.
'Note for city: enter data for either city name
i2T for FIPS city code, but not both.
2Note for plant location: enter data for either
lat/long sn UTM, but not both.
List of Data Elements for Point General Level:
Description
**F1PS stale code
**FIPS county code
~~plant ID from AFS (or NEDS)
• ID ficwmi AFS
local point ID
. hoursper day
days per week
hoars operated per year
start time (each workday)
end time (each workday)
percent: throughputDec.thruFeb.
percent throughput * March thru May
percent throughput - June thro Aug,
percent throughput * Sept. thru Nov*
boiler capacity
space heat percentage
point comment
% Required for 03/C0 SIP emission inventories.
* * Mandatory for both Adds and Changes to AFS.
57
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List of Data Elements for-Point Pollutant Level:
Description
**FIPS state code
**FIPS county code
*'plant ID from AFS (or NEDS)
•"point ID from AFS
"pollutant code or CAS code
measured emissions at point
emission measurement method code
measured emissions units
SIP regulation in place for point
compliance year for point
emission limitation for point
emission limitation value
emission limitation units
*' Mandatory for both Adds and Changes to AFS.
List of Data Elements for Stack Level:
Description
**F1PS stale code
•~FTPS county code
••plant ID from AFS (or NEDS)
••stack R> from AFS
*staek height w
•stackdlameter(ft)w
•plume height (vent height, ft)w
latitude for stack2,3
longitude for stack24
UTM easting for stack2,3
UTM northing for stack2,3
temperature of exit gases (F)
exhaust gas flow rate (ACFM)
exit gas velocity (ft/sec)
Required for 03/C0 SIP emission inventories.
58
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* Mandatory for AFS format, for Adds.
* * Mandatory for both Adds and Changes to AFS.
'Note: required either to enter stack height and
stack diameter to enter plume height (vent height).
2Note: for Stack location (if different from Plant),
enter either lat/long £r UTM, but not both.
3Note: required for AFS only if a stack exists and stack
ID has been entered; for SIP inventories, this parameter is
not required if no stack exists or if photochemical modeling
is not required for an attainment demonstration.
List of Data Elements for Segment General Level:
Description
~•FlPSstkte code
"FlPScoiraljfcode
~~plant ID front AFS (or NEDS)
~~point ID flront AFS
**s^ra«itlDfinoniAFS
~SCC number
sulifur percentage
ash percentage
heat content
confidentiality
process rate units
actual anattalprocess rate*
maximum design rate2
season process rate (daily)2
CO season process rate (8 hr.)2
stack ID related to this segment1
segment comment
; Required for 03/C0 SIP emission inventories.
" Mandatory for AFS format, for Adds.
59
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** Mandatory for both Adds and Changes to AFS.
'Note: required for AFS only if a stack exists; for SIP inventories,
this parameter is n£j required if no stack exists or if photochemical
modeling is not required for attainment demonstration.
2Note: these parameters must be provided unless they are deemed to
be confidential or their reporting is prohibited by State law.
List of Data Elements for Segment Pollutant Level:
Description
**FIPS state code
•~HPS county code
~•plant ID from AFS (or NEDS)
~~pointlDft-ontAFS
"segment ID from AFS
~~pollutant code or CAS code
primary control device code1
secondary control device code1
control efficiency?
SIP regulation in place for segment
compliance year for segment
emissionlimitation "description for segment
emission limitation; value
emission limitation units
emission estimation metbod
emission factor2
seasonal adjustment factor
annual noubanked emissions (estimated actual)
annual banked emissions
rule effectiveness3
Q3 season emissions (lb/day)
CO season, emissions (lb/8 Itr.)
J Required for 03/C0 SIP emission inventories.
'* Mandatory for both Adds and Changes to AFS.
60
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'Note: required for SIP inventories only when a control device exists.
2Note: required for SIP inventories only when the emission estimation
method code indicates that an emission factor was used (i.e., method
codes 3 and 5 for SAMS reporting or method code 9 for AFS batch
format reporting). For other method codes, an emission factor does not
apply and is not required.
3Note: required for SIP inventories only when rule is in place that affects
emissions of the pollutant.
The National Air Data Branch is developing a new AIRS subsystem to
handle the area and mobile source inventories. The new mainframe software is called
AIRS Area and Mobile Source Subsystem (AMS) and will facilitate State data entry,
update, and access to area source data. Since AMS will not be able to upload State data
in formatted transactions until May 1992 (AMS "National" capability by November 1992),
AMS data entry software is being developed on a personal computer (PC).
States have three basic options to submit their area source data. However,
please note that option 3 will not be available in time for the draft area and mobile
source inventory submittals but could be used for final base year submittals or periodic
inventory updates.
4.8 2
Area and Mobile Source Inventory
Option
When Available
(1) AMS-PC Version 1.0
June 28, 1991
(2) AMS Batch Transaction
Format Available
July 31, 1991
(3) AMS Mainframe Interactive
Direct Entry
May 29, 1992
61
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Option (1)
The AMS-PC package will be available to the States by June 28, 1991.
States may use the AMS-PC package to submit their 1990 base-year inventory for area
and mobile sources. The AMS-PC Version 1.0 will be a basic data-entry system for
State-prepared emissions values, and will have only minimal calculation capabilities. The
AMS-PC package will be compatible with the mainframe AIRS AMS in categories,
codes, and edits, and will be consistent with EPA's guidance for SIP 1990 base-year
inventories. Note that SAMS Version 4.0 and Version 4.1 will noi provide the
appropriate categories and formats to develop the 1990 area source or mobile source
inventory; therefore, SAMS cannot be used for the purpose of submitting AMS inventory
data.
Option (2)
States planning to transmit a computer generated data set or magnetic tape
file will need to supply data in EPA's AMS batch transaction format. This format will
be defined and distributed to the States in July 1991. Tape submitted data should be
structured in IBM EBCDIC.
AMS transactions generated from the AMS-PC and AMS batch
transactions generated and submitted from State computers will be updated to the AMS
mainframe data base. The capability to update this SIP data to the mainframe is
scheduled for May 1992. During the period of January through May, 1992, the Technical
Support Division will provide assistance with basic edits and review of draft inventories
submitted as AMS batch transactions from State computers. The Regions and the States
will receive additional information and guidance regarding area and mobile source
procedures in the near future. State personnel should contact John Ackermann or Sue
Kimbrough of NADB to indicate what type of approach will be used for their area and
mobile source inventories.
62
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Option (3)
The AMS mainframe data entry capability for area and mobile source data
will be available in May 1992. States will be able to do corrections, updates or
projections interactively to base year data existing or imported into AMS. States
planning to use this approach will need AMS training and should coordinate their
submittal plan with Sue Kimbrough of NADB, at (919) 541-5457 (FTS 629-5457).
4.8 J Format Tor Area and Mobile Source Data
Previously, the SIP guidance documents and the SAMS system provided for
a series of source categories that ranged from the detailed level to a very aggregated
level. However, the source category codes developed for use within AMS have been
designed to encourage the user to submit data at a more detailed level. Therefore, the
AMS source categories are significantly different from the manner in which source
categories have been designated in past SIP guidance. These source category codes and
descriptions will be listed in the more detailed guidance documents that will be issued
over the next few months.
4.9 Statewide Point Source Emission Inventories for Regional Modeling
EPA plans to perform regional scale photochemical modeling for domains
covering the Eastern U.S., east of longitude 99 degrees W to provide States with a
number of critical data bases for use in urban scale modeling required for SIP
demonstrations in certain nonattainment areas (see Section 2.2.1). Estimates of
future-year air quality concentrations will be provided for use in specifying urban scale
boundary conditions (i.e., incoming transported concentrations) and initial conditions.
Additional meteorological and geographic data bases available from the regional
modeling applications will also be provided to the States by EPA The future-year
concentration estimates quantify the effects of projected growth, Federal/subregional
63
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control programs (e.g. FMVCP and alternate fuels), and local control measures in
upwind areas.
For consistency with urban scale modeling, 1990 emissions are needed for
the base case regional inventory. States in EPA Regions I through VII are requested to
develop the point source emissions needed for this inventory. This consists of a
statewide 1990 point source inventory for VOC, NO^ and CO for facilities that emit
greater than or equal to 100 tons per year. This inventory is essentially the same as
traditionally required for an annual "NEDS" submittal (this submittal is now being
handled through the AIRS-AFS). Data elements required to be reported with this
inventory are identified in Section 4.8. These statewide inventories should be prepared
in a manner consistent with those developed for nonattainment areas. Guidance
documents and schedules for planning, developing, quality assuring, and submitting point
source inventories are identified in Sections 3.4, 3.10, 3.11.1, and 4.1.
64
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5.0 PLANNED MILESTONES AND SCHEDULES
This section presents a discussion and graphical illustration of the
milestones and planned EPA schedules connected with Title I of the CAAA generally
and with emission inventories specifically. The two-fold purpose of the discussion is to
provide a description of the guidance, training, and inventory activities that will be taking
place with States and EPA under Title I between CAAA enactment and 1994, and to
provide a listing of the different inventory milestones that exist for varying classifications
of nonattainment areas.
Figure 1 depicts EPA's overall schedule for the implementation of Title I
ozone and CO inventory activities. The schedule illustrates when the base year inventory
milestones occur, when EPA guidance materials are to be issued, and when training
sessions with the States are to be held. The
as follows.
Item
Statesinitiate Iraseyearinventoiy
data collation
States initiate
plandevelopment
O, and CO SIP inventory requirement*
documentsissued
Pfeotodiemicai modeling inventoiy
guidance issued
Februaiy I99J
February 1991
March 1991
May mi
65
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Issue
Area/MobDe
Guidance
Issiio Imairiitbfy
ReqUtaitdnta:
DocOnwnta
(For CXJ » CO)
¦GwflnflSturtetf
aMaim''"
'91
+H
O N D
I
E
Issue'
UAM El i
Guidance
Conduct
Wpttotofw
Bnaflzo
Review.
Gukte»ne«
tlrtttW -
Gtfcteflce ¦
teftOe
Profcctlofl
Outdance
Draft 1880 El'c Dim
•92
'93
'94
*95
iwhiiii iimliini
-1 iti ffn 11 n -
> fIm am| jP a so n d
SWm Basin Si alee Begin 1 -VT* ' '
B Plana A Area/Mottle J
lllllllllll
fH-H-
%
FMAMJ J ASOND
I
FMAMJ J ASOND
I
FMAMJ J
1
St alee Bagln
State* Bagln
EiPtanaS
Area/Mottle
R Sauce Era
Inventories
CAAA Signed
QMS liaiea
(Nov. 16,-90)
Revised
M08LE4
Inventory A
OA Plain
Submitted!
Agraad Upon
SUlea Bagln Submitting
Dull Inventories:
EPA (WHO Begin
Inventory Reviews
j ?..y| Emission Inventory Branch Activities
~ Title I Requirements
2-yr
•Final" OS/CO El Dua
03 SlPa Raqulia
Emission Slstemente
CO SIP Dua
ml El Projector*
3-yr
6 Yr RFP Plan
Dua ml Projections
(Moderate ~(
ASOND
I
4-yr
L
Emlulon Statements
Qua tor VOC. NOi
(tor CY 02)
03 SIP Dua
7 Yr ~ RFP Plan
Dua w/ Projections
(Serious ~)
Attainmanl Damo
Dua •»/ Modeing El
(Serious 4)
Attainmanl Damo Dua
(Modarala Amaa)
X
Emission Statements
Oue lor VOC. NO«
(lor CY 'S3)
Figure 1. Title I Ozone/CO Emission Inventory Timeline
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New area/mobile source guidance issued May 1991
Updated MOBILE4 model Issued May 1991
Conduct training workshops with States June 1991
States finalize inventory preparation plans . M^i-^niw-1991
and submit to EPA for review*
Qaaiity review guiddtow tesoed j
Projection guidance issued
Inventor; preparation and QA plans October 1991
finalized and approved b; EPA
RJFP tracking guidance issued November 1991
Draft 1990 base year inventories submitted January-May 1992
to EPA Ibr review
EPA provides comments to States on draft April-August 1992
inventories
States submit final inventories November IS, 1992
EPA expects States to generally initiate 1990 base year inventory
preparation activities in February 1991 even though not all necessary guidance materials
will be available at this time. Since the majority of the emissions estimating guidance for
point sources remains unchanged from the previous Post-1987 Policy, there are numerous
data collection activities that States can begin. As a part of these initial efforts States
should begin thinking about how they plan to present their inventory preparation plan
and their QA plan. As the guidance and training schedule under the CAAA proceeds,
these plans should become more and more concrete. Stale* need tbfceep lit mind that
they have to submit and gala approval of an inventoiy preparation plan as an Initial
step In the tnventoiy compilation; The sooner this plan is developed and submitted for
approval, the sooner States can proceed with full inventory preparation activities. As
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discussed in Section 3.10 on QA, States need to include with the inventory plan a QA
plan component or submit a separate' QA plan in conjunction with the inventory plan.
The dates shown in Figure 1 for these types of activities should be viewed as upper limits
not to be exceeded. EPA encourages States to complete all of the specified milestones
as soon as they are able, as this will provide more time for addressing comments and
revisions and for subsequent activities such as RFP planning and modeling.
Draft 1990 base year emission inventories must be submitted prior to
May 1,1992 to ensure that adequate time is available for review and revision of
inventories by November 15, 1992, the required date for final inventory submittal.
Allowing this extra review time will help ensure that the final inventories are complete,
comprehensive, and meet all EPA specifications. States are encouraged to submit draft
inventories as early as January 1, 1992, particularly for draft point source inventories.
States must consult and coordinate inventory submittal schedules with their respective
Regional Offices to ensure that all inventory components are prepared and delivered in
accordance with these dates.
EPA will review the submitted inventories and provide comments back to
the States within three months. States then need to address the EPA comments and
provide final inventories to EPA by November 15, 1992, the date required by the CAAA.
EPA anticipates that the respective Regional Offices will take the lead on performing
detailed inventory review. EPA headquarters will provide more of an oversight function
to ensure consistency among the Regions.
versions) should be copied toEPA headquarters (OAQPS) at tbe same time they are
sent to the Regional Offices* The total inventory package should be sent to OAQPS to
the attention oft Chief, Inventoiy Guidance aad Evahtatfon Section* Emission inventory
Branch (MD-14), Technical Support Division* U» & Environmental Protection Agency,
Research Triangle Park, N.G* 277ll« Portions ofthe fiwentoriea deafin^vMth mobile
source emissions shouldbe directedto Ms. Jute Airosttt^ofthe Office ofMobile
Sources, Test and Evaluation Branch (TEB-13), XL S. Environmental Protection Agency,
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25^ Hyinoatii Road, Ann Arbor, Michigan, 4S105. In addition to specific inventory
materials of any type, States shoald~also copy EPA faeadqaarters on all correspondence
pertaining to their inventories soch as comment letters, modiflkations to theiir 1PP or
QA plan, etc.
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6.0 ADDITIONAL GUIDANCE TO BE ISSUED BY EPA
The purpose of this section is to identify and describe the contents of
additional guidance materials EPA plans on releasing in 1991 to respond to the inventory
requirements of the CAAA. This guidance will take the form of both hard copy reports
and memos and training workshops with the State and local agencies responsible for
developing inventories. Most of these additional guidance materials will be issued in the
spring and no later than the summer of 1991. Regardless, States should begin thinking
about the issues to be covered in the additional guidance materials and begin
formulating ways to address the basic informational needs. For example, even though
formal projections guidance is not scheduled for release until July, States can certainly be
thinking of ways they can address this issue with their point, area, and mobile sources
(i.e., what data need to be gathered, what data are available, for my sources, how can
these best be gathered, etc.).
Soo& after the distribution of this Initial CAAA inventoiy guidance, EPA
will beprovldiogStaies withnew inventory "Retirements Documents" that will be very
similar to form and content to the similar documents issued under the proposed Post-
1987 Pollq? fEmission Inventory Requirements for Post-1987 Ozone State
Implementation Plans (EPA 450/4-88-019) and Emission Inventory Requirements for
Post-1987 Carbon Monoxide State Implementation Plans (EPA 450/4-88-020)]. The new
Requirements Documents will reflect in detail the inventory requirements States are
facing under the CAAA in terms of both direct statutory requirements and EPA policy
requirements formulated in response to the new Act. In effect the documents will
provide more detail on many of the points preliminarily raised in this discussion. The
information in the documents will focus on the base year inventory requirements and will
generally not be subject to change. Two new Requirements Documents wlB befssued,
one for ozone inventorie&and onefcrCO* EPA plans to ffistrihute thesedoenments to
States in March 199L
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The second type of guidance EPA will be issuing concerns the development
of emission inventories for use in urban airshed modeling (UAM). lit May 1991, EPA
Mill provide Stales with guidance oit how inventories seed to be prepared in order to
support photochemical air quality:m
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process will be evaluated by EPA as it becomes available and will depend on the
significance to the overall inventory (see Backcasting, Section 4.4).
In May 1991, EPA will release a new version of Itsr mobile source emission
factor model, llieaew;vendont;:will;:'reptli^icbe;eiui^ version
of MOBILE4i For 1990 base year emission inventories under the CAAA, EPA is
requiring that States, with the exception of California, use the updated model version to
determine highway mobile source emissions. The changes in MOBILE4 are relatively
minor in terms of how they will affect a State trying to use the new model. Most of the
improvements are internal to the model such that the requirements on a State using the
model are not really any different or more significant than they were for the previous
MOBILE4 version. A new MOBILE4 User's Guide will be issued that details all
changes and assists users with clear step-by-step instructions on model execution. Since
EPA is requiring that all nonattainment areas prepare new 1590 mobile source
inventories, the added requirement to incorporate the updated MOBILE4 model should
not present a significant or undue burden on any State.
As discussed in Section 3.9, the projection of emissions to future years is
still an important inventory function under the CAAA There are several requirements
for projected emission inventories. For th$» reason; EPA, Is developing formal, detailed
guidance for States to use la preparing eraisskmsprojeetions. The guidance is slated
for distribution in July 1991* The guidance will address the performance of projections
for stationary point and area, off-highway mobile, and highway mobile sources.
Whenever possible, EPA encourages States to use site-specific and source-specific data in
calculating projected emissions. In cases where such data are not easily available, EPA
guidance will provide States with alternative approaches and sources of data to
implement the approaches. Any source surveys States are planning on conducting to
gather data for the 1990 base year inventory should include questions regarding source
growth and expected changes in factors that affect emissions.
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in May 1991y EPA will also be providing guidance on one of the new
requirements of the CAAA, Emissions Statemeats. The basic requirements of Emissions
Statements are described in Section 4.3. At this time, EPA is still formulating the
precise form and content it wants Emissions Statements to take. Since all States with
ozone nonattainment areas are required to compile Emissions Statements, EPA wants
the statements to be developed in a standard and consistent manner to better facilitate
EPA review and to maximize their potential use in other activities such as emissions
tracking. The guidance will address the temporal basis for the estimates (annual, daily,
hourly, other, etc.), the specificity of the estimates (total plant, each emission point, each
process unit, etc.), the level of documentation required for the statement, and the
required reporting format (written and computerized).
Ia July 1991, EPA Is .planning on providing Slates with guidance material
that will be heipfiil not only in checking the compiiedf^entfeiy prior lo salhnission to
EPA, hut also ill designing how to begto preparatioa of the overall effort. This guidance
will take the form of quality review guidelines. The quality review guidelines will allow
States to check whether or not they followed the requirements for inventory preparation
issued by EPA and whether their inventories meet the specifications developed for
completeness, consistency (both internal and national), reasonableness of emission
values, and overall documentation requirements. The guidelines will be beneficial to
States in designing and conducting their inventory QA program. Once finalized, the
review guidelines will serve to supersede the quality review checklist given in Appendix B
of the previously published Requirements Documents. The guidelines will also present
EPA Regional offices with a standard set of guidelines to use in conducting formal
reviews of ozone and CO SIP inventories.
As was done In connection with the proposed Post-lSBT PoHqv EPA plans
to conduct regional workshops with State and local agencies to present and dlscuss nil
relevant CAAA emission inventory issues and requirements Identified in this document,
these workshopsare currently projected for late Spring-early Slimmer of 1991. EPA
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hopes to have most of the planned guidance in States' hands before the workshops begin,
but it is likely that not all materials will be available before the workshop discussions.
Although the form and agendas for the workshops have not yet been set, it is likely that
they will be multiday events at which the participants will have a significant opportunity
for questions and interaction with appropriate EPA Regional Office and Headquarters
personnel. The dates and locations for the workshops will be communicated as soon as
they are determined.
Guidance documents that are planned or under development are listed
below along with an expected date of release.
1. Requirements for 03 and CO SIP emission inventories. March
1991.
2. Revision of Procedures for the Preparation of Emission Inventories
for Precursors of Ozone. EPA 450/4-88-021. May 1991.
3. Revised guidance for mobile source emission inventories including
vehicle miles travelled. May 1991.
4. Guidance on preparing emission inventories for photochemical grid
modeling. May 1991.
5. Finalize inventory review guidelines. July 1991.
6. Emission inventory projection guidance. July 1991.
7. RFP tracking guidance. November 1991.
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7.0 EXISTING EPA GUIDANCE FOR OZONE/CO EMISSION INVENTORIES
The purpose of this section is to identify and provide bibliographic citations
of currently existing EPA guidance materials for the development of ozone/CO SIP
emission inventories. The list of existing guidance is divided into four categories:
ozone/CO SIP inventory guidance/requirements, quality assurance/inventory review
guidance, emission factors/models, and general inventory guidance. If updates to an
existing document are planned in response to the CAAA, this is indicated in the
guidance citation.
Ozone/CO SIP Inventory Guidance/Requirements
1. Procedures For The Preparation Of Emission Inventories For Precursors
Of Ozone. Volume I. EPA-450/4-88-021, Third Edition, U. S.
Environmental Protection Agency, Office of Air Quality Planning and
Standards, Research Triangle Park, NC, December 1988. [Revised version
to be completed in May 1991.]
2. Procedures For The Preparation Of Emission Inventories For Volatile
Organic Compounds. Volume II: Emission Inventory Requirements For
Photochemical Air Quality Simulation Models. EPA-450/4-79-018, U. S.
Environmental Protection Agency, Office of Air Quality Planning and
Standards, Research Triangle Park, NC, September 1979. [Revised version
to be completed in May 1991.]
3. Procedures For Emission Inventory Preparation. Volume IV: Mobile Sources.
EPA-45O/4-81-026d, U. S. Environmental Protection Agency, Office of Air
Quality Planning and Standards, Research Triangle, Park, NC, July 1989 (also
listed below under General Inventory Guidance). [Revised version to be
completed in May 1991.]
4. Emission Inventory Requirements For Post-1987 Ozone State Implementation
Plans. EPA-450/4-88-019, U. S. Environmental Protection Agency, Office of
Air Quality Planning and Standards, Research Triangle Park, NC, December
1988. [Revised version to be completed in March 1991.]
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5. Emission Inventory Requirements for Post-1987 Carbon Monoxide State
Implementation Plans. EPA-450/4-88-020, U. S. Environmental Protection
Agency, Office of Air Quality Planning and Standards, Research Triangle
Park, NC, December 1988. [Revised version to be completed in March 1991.]
6. Example Emission Inventory Documentation For Post-1987 Ozone State
Implementation Plans (SIPs^. EPA-450/4-89-018, U. S. Environmental
Protection Agency, Office of Air Quality Planning and Standards, Research
Triangle Park, NC, October 1989.
7. Procedures For Estimating And Applying Rule Effectiveness In Post-1987
Base Year Emission Inventories For Ozone And Carbon Monoxide State
Implementation Plans. U. S. Environmental Protection Agency, Office of Air
Quality Planning and Standards, Research Triangle Park, NC, June 1989.
8. SIP Air Pollutant Inventory Management System (SAMS') Version 3.1 and
SAMS User's Manual. U. S. Environmental Protection Agency, Office of Air
Quality Planning and Standards, Research Triangle Park, NC, April 1990.
[Revised version to be completed in March 1991.]
Quality Assurance/Inventory Review Guidance
9. Guidance For The Preparation Of Quality Assurance Plans For O^/CO SIP
Emission Inventories. EPA-450/4-88-023, U. S. Environmental Protection
Agency, Office of Air Quality Planning and Standards, Research Triangle
Park, NC, December 1988.
10. Quality Assurance Program For Post-1987 Ozone And Carbon Monoxide
State Implementation Plan Emission Inventories. EPA-450/4-89-004, U. S.
Environmental Protection Agency, Office of Air Quality Planning and
Standards, Research Triangle Park, NC, March 1989.
11. Quality Review Guidelines For Post-1987 State Implementation Plan (SIP1
Base Year Emission Inventories (Draft), U. S. Environmental Protection
Agency, Office of Air Quality Planning and Standards, Research Triangle
Park, NC, February 1990. [Final version to be completed in July 1991.]
12. Guidelines For Review Of Highway Source Emission Inventories For 1982
State Implementation Plans. EPA-450/12-80-002, U. S. Environmental
Protection Agency, Research Triangle Park, NC, December 1980. [This
document will be superseded by the Quality Review Guidelines document
above, to be completed in July 1991.]
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General Inventory Guidance
13. Procedures For Emission Inventory Preparation. U. S. Environmental
Protection Agency, Office of Air Quality Planning and Standards, Research
Triangle, Park, NC:
a. Volume I: Emission Inventory Fundamentals. EPA-450/4-81-026a,
September 1981.
b. Volume II: Point Sources. EPA-450/4-81-026b, September 1981.
c. Volume III: Area Sources. EPA-450/4-81-026c, September 1981.
d. Volume IV: Mobile Sources. EPA-450/4-8l-026d (Revised), July 1989.
[Updated version to be completed in May 1991.]
e. Volume V: Bibliography. EPA-450/4-81-026e, September 1981.
Emission Factors/Models
14. Compilation of Air Pollutant Emission Factors. Volumes I and II and its
supplements, Fourth Edition, AP-42, U. S. Environmental Protection Agency, Office
of Air Quality Planning and Standards, Research Triangle Park, NC, September
1985.
15. AIRS Facility Subsystem Source Classification Codes (SCCs) And Emission Factor
Listing For Criteria Pollutants. U. S. Environmental Protection Agency, Office of Air
Quality Planning and Standards, Research Triangle Park, NC, September 1989.
16. User's Guide to MOBILE4 (Mobile Source Emission Factor Model). EPA-AA-TEB-
89-01, U. S. Environmental Protection Agency, Office of Mobile Sources, Ann Arbor,
MI, February 1989. [Revised version of MOBILE4 and documentation to be
completed in May 1991.]
17. Surface Impoundment Modeling System (SIMS) Version 2.0 User's Manual. EPA-
450/4-90-019a, U. S. Environmental Protection Agency, Research Triangle Park, NC,
September 1990.
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18. Background Document For Surface Impoundment Modeling System (SIMS) Version
2.0. EPA-450/4-90-0l9b, U. S.'.Environmental Protection Agency, Research Triangle
Park, NC, September 1990.
To obtain copies of any of these documents, contact Mary Ann Stewart at (919) 541-4340 or
FTS 629-4340.
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