^ol- 3
United States Office of Air Quality EPA-450/4-81-026c C/2,
Environmental Protection Planning and Standards September 1981
Agency Research Triangle Park NC 27711
Air ~
Procedures for Emission
Inventory Preparation
Volume III: Area Sources
-------
NOTICE
The Procedures for Emission Inventory Preparation consists of these
five volumes.
Volume I - Emission Inventory Fundamentals
Volume II - Point Sources
Volume III - Area Sources
Volume IV - Mobile Sources
Volume V - Bibliography
They are intended to present emission inventory procedures and
techniques applicable in State and local air programs, and for con-
tractors and other selected users. The object is to provide the best
available and "state of the art" information. For some areas, however,
the available source information and data either may allow more precise
procedures and more accurate estimation of emissions or may not be amen-
able to the use of these procedures. Therefore, the user is asked to
share his knowledge and experience by providing comments, successfully
applied alternative methods or other emission inventory information
useful to other users of these volumes. Please forward comments to the
U.S. Environmental Protection Agency, Air Management Technology Branch,
(MD-14), Research Triangle Park, NC 27711. Such responses will provide
guidance for revisions and supplements to these volumes.
Other U.S. EPA emission inventory procedures publications:
Procedures for the Preparation of Emission Inventories for
Volatile Organic Compounds, Volume I, Second Edition,
EPA-450/2-77-028, U.S. Environmental Protection Agency,
Research Triangle Park, NC, September 1980.
Procedures for the Preparation of Emission Inventories of
Volatile Organic Compounds, Volume II: Emission Inventory
Requirements for Photochemical Air Quality Simulation Models,
EPA-450/4-79-018, U.S. Environmental Protection Agency,
Research Triangle Park, NC, September 1979.
-------
EPA-450/4-81-026C
Procedures for Emission Inventory Preparation
Volume III: Area Sources
by
Monitoring and Data Analysis Division
Office of Air Quality Planning and Standards
U S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air, Noise and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
September 1981
-------
This document is issued by the Environmental Protection Agency to report
technical data of interest to a limited number of readers. Copies are
available free of charge to Federal employees, current EPA contractors
and grantees, and nonprofit organizations - in limited quantities - from
the Library Services Office (MD-35), U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina 27711; or, for a fee, from the
National Technical Information Service, 5285 Port Royal Road, Springfield,
Virginia 22161.
This report was furnished to the Environmental Protection Agency by GCA
Corporation, Bedford, Massachusetts 01730, in fulfillment of Contract
No. 68-02-3087. The contents of this report are reproduced herein as
received from GCA Corporation. The opinions, findings and conclusions
expressed are those of the author and not necessarily those of the
Environmental Protection Agency.
Publication No. EPA-450/4-81-026c
/-' ^Tt"v n<«n i
ii
-------
TABLE OF CONTENTS
Section Page
1.0 INTRODUCTION 1-1
1.1 Definition of an Area Source 1-1
1.2 Area Source Categories 1-2
1.3 Area Source Activity Levels 1-6
1.4 Overview of the Area Source Inventory 1-6
1.5 Purpose and Organization of the Volume 1-14
2.0 COMBUSTION SOURCES 2-1
2.1 External Combustion Sources 2-1
2.1.1 External Combustion Source Categories 2-1
2.1.2 Fuel Use 2-2
2.1.3 Data Requirements and Sources 2-3
2.1.3.1 Activity Levels 2-3
2.1.3.2 Spatial Resolution 2-3
2.1.3.3 Temporal Resolution 2-5
2.1.3.4 Emission Factors 2-5
2.1.4 Determination of State Fuel Use by Source Category . 2-6
2.1.4.1 Residential 2-6
2.1.4.2 Commercial/Institutional 2-9
2.1.4.3 Industrial 2-10
2.1.5 Determination of County Fuel Use by Source Category. 2-11
2.1.5.1 Residential 2-11
2.1.5.2 Commercial/Institutional 2-12
2.1.5.3 Industrial 2-12
2.1.6 Apportioning Fuel Consumption to Subcounty Levels. . 2-13
2.1.6.1 Apportioning Population to Grids 2-13
2.1.6.2 Apportioning Fuel Consumption 2-13
2.1.7 Calculating Emissions 2-15
2.1.8 Sample Calculations 2-15
2.2 Stationary Internal Combustion Engines 2-24
2.2.1 Population of Internal Combustion Sources 2-25
2.2.2 Estimating Fuel Consumption 2-25
2.2.3 Calculating Emissions 2-28
3.0 Solid Waste Incineration and Open Burning 3-1
3.1 Source Categories 3-1
3.2 Incineration 3-1
3.2.1 Procedures for Incinerator Emission Inventory
Preparation 3-4
3.2.1.1 Determination of Activity Level 3-4
3.2.1.2 Emission Factors for Incineration .... 3-6
3.2.2 Example Calculation: Emissions from Incinerators. . 3-6
3.3 Open Burning 3-9
3.4 Prescribed Fires. 3-10
3.4.1 Agricultural Burning 3-10
3.4.2 Slash Burning 3-10
iii
-------
TABLE OF CONTENTS (continued)
Section
3.4.3 Frost Control 3-10
3.4.4 Leaf Burning 3-11
3.5 Forest Fires 3-11
3.6 Structural Fires 3-11
4.0 FUGITIVE DUST SOURCES 4-1
4.1 Data Requirements ........ 4-2
4.2 Data Sources 4-3
4.3 Source Categories 4-5
4.3.1 Unpaved Roads 4-5
4.3.2 Unpaved Airstrips 4-7
4.3.3 Paved Roads 4-7
4.3.4 Agricultural Activities 4-8
4.3.5 Construction Activities 4-12
4.3.6 Cattle Feed Lots 4-13
4.3.7 Miscellaneous Sources 4-13
4.4 Emission Controls 4-13
5.0 VOLATILE ORGANIC COMPOUND (VOC) SOURCES 5-1
5.1 Introduction 5-1
5.2 General Procedures 5-1
5.2.1 Use of Point Source Inventorying Methods 5-1
5.2.2 Use of Local Activity Level Data 5-3
5.2.3 Apportioning State or National Data. ... 5-3
5.2.4 Per Capita Emission Factors 5-4
5.2.5 Emissions-Per-Employee Factors 5-4
5.3 Specific Methods and Techniques 5-4
5.3.1 Petroleum Liquids Marketing and Storage 5-5
5.3.2 Dry Cleaning 5-7
5.3.3 Degreasing (Solvent Cleaning Operations) 5-8
5.3.4 Surface Coating 5-11
5.3.5 Graphic Arts 5-12
5.3.6 Commercial/Consumer Solvent Use 5-12
5.3.7 Cutback Asphalt Paving 5-13
5.3.8 Pesticide Applications 5-14
6.0 PRESENTATION OF AREA SOURCE EMISSION INVENTORIES .......... 6-1
6.1 Introduction 6-1
6.2 Specific Presentation Techniques 6-1
iv
-------
LIST OF FIGURES
Figure Page
1-1 Activities for preparation of an inventory of area sources. . . 1-9
1-2 Example area source load sheet-description transactions .... 1-11
1-3 Example area source load sheet-category transactions 1-13
2-1 Procedure for determination of state area source fuel oil
use by source category 2-7
2-2 Grid coordinate system example 2-14
4-1 Map of Thornthwaite"s Precipitation-Evaporation Index values
for state climatic divisions 4-9
4-2 Climatic factor used in wind erosion equation 4-10
6-1 The distribution of fugitive particulate emissions in a survey
area 6-8
6-2 Sample emission density plot 6-9
6-3 Percentage of total daily, weekly, and annual agricultural
tilling 6-10
6-4 Example of Complex Zoning (from City of Chicago Zoning
Ordinance) 6-11
v
-------
LIST OF TABLES
Table Page
1-1 Listing of Area Source Categories 1-3
1-2 Contribution of Area Source Categories to Nationwide Emission
Totals, 1977 1-7
2-1 Statistical Data Sources for Estimating Fuel Use 2-4
2-2 Current and Projected Gas Turbine Installed Capacity for
Utility and Industrial Applications 2-26
2-3 Reciprocating Engine Installed Capacity for Utility, Industrial,
and Commercial/Institutional Applications 2-27
3-1 Solid Waste Incineration and Open Burning Source Categories . . 3-2
3-2 Incinerator Design Distribution 3-3
3-3 Factors to Estimate Tons of Solid Waste Burned in Onsite
Incineration 3-5
3-4 Factors to Estimate Tons of Solid Waste Disposal Through Open
Burning 3-10
4-1 Fugitive Dust Source Emission Factors (Uncontrolled). ..... 4-4
4-2 Emission Source Parameters and Sources of Information 4-6
5-1 Evaporative VOC Area Source Categories 5-2
5-2 Gasoline Marketing and Storage 5-5
5-3 Solvent Cleaning Emissions by SIC Category 5-10
6-1 State of New Hampshire 1985 Area Source Pollutant Emissions
(Tons/Year) . 6-2
6-2 Solid Waste Commercial-Institutional Incineration Emissions
(Tons/Year) in AQCR 70 for 1973 6-3
6-3 Reactive Organic Emissions, Tampa Bay 6-4
6-4 Summary Table of Reactive VOC Emissions for Geographical Area . 6-5
VI
-------
1.0 INTRODUCTION
Methods and procedures for preparing and maintaining an inventory of
emissions from area sources are presented in this document. The inventory of
area source emissions, together with the inventories of point and mobile
source emissions, provide a complete representation of pollutant emissions
within a given geographical area. A complete and reliable emission inventory
serves as the basic tool for the effective development of air quality
management plans and programs.
This volume is the third of a multivolume series designed to assist
control agency personnel in preparing an emission inventory of air pollutants
and deals specifically with preparing the area source inventory. The other
volumes of the series are: Volume I which presents the fundamentals of
preparing an emission inventory and is intended to serve as a basic managment
tool for planning and maintaining the inventory; Volumes II and IV which
provide procedures for preparing inventories of point and mobile sources,
respectively; and Volume V which is a bibliography of pertinent emission
inventory literature.
1.1 DEFINITION OF AN AREA SOURCE
Stationary area sources represent a collection of many small,
unidentified points of air pollution emissions within a specified geographical
area, all emitting less than the minimum level prescribed for point sources.*
Stationary area sources are defined in Reference 1 as (1) those activities for
which collective source and emissions information is maintained in the
emission inventory, and (2) sources not considered as point sources by the
agency. Because these sources are too small and/or too numerous to be
surveyed and characterized individually, all area source activities must be
identified and emissions from these activities collectively estimated.
The county is usually the geographical area for which emissions from area
sources are compiled, primarily because counties are the smallest areas for
which data used for estimating emissions are readily available. In states
where counties are not the principal political jurisdiction below the state
level, county equivalents such as cities, census divisions, parishes, or towns
*Federal regulations (40 CFR 51) have required state agencies to identify as
point sources any facility which emits more than 90.7 metric tons (100 tons)
per year of particulate matter, sulfur oxides, nitrogen oxides, hydrocarbons,
or carbon monoxide. Any source that emits more than 4.54 metric tons
(5 tons) per year of lead must also be identified as a point source. Annual
emissions of point sources subject to the reporting provisions of Subpart
51.321 are identical to those above with the exception that for carbon
monoxide only sources emitting 907 metric tons (1,000 tons) per year are
subject to the annual report requirements. No submission of area source data
is required by 40 CFR 51. An agency will usually determine the cut point
between a point source and an area source based on its applicable regulations
for source categories and pollutants. Generally, when considering hazardous
pollutants, point sources would be identified as all known emitters.
1-1
-------
can be used. Certain applications of the emission inventory will require more
detailed spatial resolution than that provided at the county level. In such
cases, county emissions must be apportioned to square grid zones of
appropriate size using techniques that will be described in this volume.
1.2 AREA SOURCE CATEGORIES
The agency must establish area source category definitions by identifying
activities possessing similar operating and emission characteristics that can
be grouped together and handled collectively. Area sources can be grouped
into four types of general activity categories:
Fuel combustion sources,
Solid waste incineration and open burning sources,
Fugitive dust sources, and
Volatile organic compound sources.
These major groupings can be further divided into subcategories to facilitate
the accurate estimate of emissions based on the application of emission
factors to activity level information.
Table 1-1 lists a number of area source categories within each of the
four major activity areas listed above. These area source categories are
listed for example only, and do not represent all potential area source
categories. An agency will want to prepare its own working list based on
sources within its jurisdiction and the level of detail desired. Some of the
categories listed may not exist in a given area; others may be prohibited by
regulation; and some categories may be missing from the examples in Table 1—1.
Mobile sources have not been included in this table. Methods for developing
an inventory of mobile source emissions are presented in Volume IV.
The area source categories that are used by EPA's National Air Data
Branch (NADB) to compile and report area source data are also shown in
Table 1-1. An agency may wish to use these categories because of the computer
programs available from EPA to apportion and report area source emissions.
The agency should obtain a description of available computer programs and
reports by contacting the U.S. Environmental Protection Agency, National Air
Data Branch, Mail Drop 14, Research Triangle Park, North Carolina 27711.
Many of the source categories in Table 1-1 will be handled strictly as
area sources. However, some source categories will consist of both point and
area sources. Care must be taken to avoid inclusion of emissions from point
sources in the agency's area source emission data file.
The selection and structuring of area source categories are important
aspects of the planning process that affect the resources required for
compilation and maintenance of an emission inventory. Because an important
use of the inventory is to study the effects of applying various control
measures, the area source categories should be defined so that emission
reduction from anticipated controls can be readily summarized from the data
maintained in the area source files. For example, if the effect of vapor
recovery of gasoline tank truck unloading emissions at service stations
1-2
-------
TABLE 1-1 LISTING OF AREA SOURCE CATEGORIES
a
Combustion by Fuel (all criteria pollutants)
Residential
Commercial/Institutional
Industrial
Stationary Engines
Solid Waste Incineration (all criteria pollutants) and Open Burning
Sources (all criteria pollutants—primarily particulates,
carbon monoxide, and volatile organic compounds)
Residential Incineration and Open Burning3
Commercial/Institutional Incineration and Open Burning3
Industrial Incineration and Open Burning3
Governmental Incineration and Open Burning
Prescribed Burning
Slash Burning3
Agricultural Burning3
Leaf Burning3
Frost Control (orchard heaters)3
Forest Wildfires3
Structural Fires3
Fugitive Dust (particulates)
Unpaved Roads3
Q
Unpaved Airstrips
Paved Roads
(continued)
1-3
-------
TABLE 1-1 (continued)
Construction Site Activity3
Land Tilling3
Tilled Land
Harvesting
Feed Lots
Pesticide Residues
Miscellaneous Wind Erosion3
Miscellaneous Sources
County Grain Elevators
Fertilizer Mixing
Feed Grain Preparation
Sawmills
Scrap Metal Salvage
Metal Melting and Casting
Aggregate Storage/Handling
Structural and Dimensional Stone Preparation
Woodworking Operations
Evaporative Loss of Volatile Organic Compounds (VOC)
Solvent Purchased (consumed)3
Gasoline Marketing3
Fuel Storage/Handling
Surface Coating
Print Shops
(continued)
1-4
-------
TABLE 1-1 (continued)
Degreasing
Dry Cleaning
Cutback Asphalt
Natural Gas and Petroleum Field Operations
Pesticides
Household Products
Miscellaneous Sources
Fermented Beverages
Auto Body Shops
Plastics Processing
Categories included in the NADB file of area source categories.
1-5
-------
(Stage I control) is to be evaluated, then these operations should be
distinguished from vehicle fuel tank loading (Stage II control) emissions.-*
As another example, in order to estimate the effect of RACT on dry cleaning
plants, those systems using perchloroethylene must be maintained in the
emission inventory separate from those using petroleum (Stoddard) solvents
because of the different control technologies that may be applied to each
solvent system.
Nationwide emissions (1977) from major stationary area source categories,
plus national totals of point and mobile source emissions, are shown in
Table 1-2. This table was developed from information shown in Reference 4 and
is presented here to provide some perspective to the agency in its allocation
of resources for preparing inventories of area sources. Because the totals
are nationwide totals, the agency should recognize that the relative
contributions of the source categories shown may differ greatly at the local
level. The miscellaneous category, solvent evaporation loss, accounts for
about 70 percent of hydrocarbon (or VOC) emissions from stationary area
sources; the agency should develop a subcategory breakdown of this category
arid maintain the subcategories in the inventory. Procedures for doing so are
discussed in Chapter 5.
1.3 AREA SOURCE ACTIVITY LEVELS
Area source emissions are estimated by multiplying an emission factor by
some known indicator of collective activity for each source category within
the inventory area. An indicator is any parameter associated with the
activity level of a source, such as production, employment, or population,
that can be correlated with the air pollutant emissions from that source. For
example, emissions of volatile organic compounds from dry cleaning facilities
in an area correlate well with population; thus, it is possible to develop a
per capita emission factor which can be used to estimate emissions. As
another example, the total amount of gasoline handled by service stations in
an area can be used to estimate collective evaporative losses from gasoline
handling.
Several methods are available for estimating area source activity levels
and emissions. Estimates can be derived by (1) treating area sources as point
sources, (2) surveying local activity levels, (3) apportioning national or
statewide activity totals to local inventory areas, (4) using per capita
emission factors, or (5) by using emissions-per-employee factors. Each method
has distinct advantages and disadvantages when used for developing area source
emissions estimates. The merits of these methods must be evaluated on a
source category-specific basis.
1.4 OVERVIEW OF THE AREA SOURCE INVENTORY
The importance of developing a reliable inventory of area source
emissions cannot be overemphasized. The contribution of area source emissions
within a given locality can be very significant. In many locations, area
1-6
-------
fc^
0\
«— (
w
g
H
|
M
tO
i
P-4
Q
H
(-*
O
M
t~J
^5
IS
O
H
3
n
8
w
H
O
1
o
&J
^>
1*3
^^
fn
O
55
O
M
F**j
^_j
pa
ed
H
0
0
CN
1
H
,-1
5
H
CU
c -o
o •-<
*£> X
li 0
CO C
s
en
C
o
JD
CO
o
M
•^
i
CO
CU
•v^
cn
C X
0 0
4J *2
"
c
CO
4-1
3
O
O,
X
o
CO
1-1
CM CM r-l
in •— 1 r-l
ON 00 r-i
00 r-« «-H
m co "d"
00 r-l CO
CO CO CO
ON *n o
00 -d CM
r- 4 r~- ON
CM in ON
co s
Residential
Commercial/
Industrial
CM
r- 1
vO
O
00
CM
CM
0
o-
in
00
r--
r-H
r— i
r^.
O
ON
m
0
oo
CM
0
CO
-^
*&
CO
^
1— 1
03
w
o
a.
cn
•r4
Q
U)
cd
T3
•H
r-l
O
cn
r— N£> ON
co in i-"i
CO vD r-l
00 r^ O
»n r** in
r— t
CM
CM r-- r-i
ON CM CM
r-t in oo
r-4 ON CM u*i !"*• m
r-< ^j o "~^ oo co r^»
m CM r-< C/)
M -< r-<
M cUl "O CQ r-l *>~* 1-1 C-OO*H CTJ
^ ri J2 4J 4) O
D *-•* 4J C *O "^ *H
r-t
<
r-l
r-
ON
0
CM
^5
CM
r-*
r-.
CM
r-l
CO
*&
r^
m
r-H
T3 O
cn C c
3 eo u
E • B CU
O -3- O M-i
CJ -H rt)
0) 4.J cd
-HO CO "
CO a V-
cm cu
^ r-l C 0)
01 a) -H o
4J e4H cj M
X 0) C 3
W pi l-l o
co a co
1-7
-------
source emissions are the principal cause of nonattainment of National Ambient
Air Quality Standards (NAAQS), thus requiring significant and special
attention by the agency if air quality standards are to be met and maintained.
The development of a complete and reliable inventory of area source
emissions requires careful planning and documentation of the data and
procedures used to compile the inventory. A flow chart depicting an overview
of the activities involved in compiling emissions from area sources is
provided in Figure 1-1. As a first step in the inventory development, the
agency planners must identify the objectives of the inventory and the
resolution necessary to achieve those objectives. The area to be inventoried,
the inventory base year, and the extent of the spatial and temporal resolution
required should be established. The status of the existing inventory should
also be evaluated, because of its impact upon the effort needed to compile the
new inventory. The existing inventory must be examined to determine whether
or not all appropriate area sources have been included and to see if the
emission data therein are representative of current conditions. Information
concerning data sources, specific emission factors, and the use of activity
indicators are generally applicable to inventory effort maintenance activities.
Planning is also necessary to define the area/point source cutoff level
and identify the area source categories of significance within the area to be
inventoried. These actions will enable the planner of the inventory to
specify: data needs and sources of information; methods for apportioning
activity levels and calculating and projecting emissions; and data handling,
analysis, and reporting procedures. Further definition of manpower and time
requirements will also be provided as a result of the above activities.
The actual conduct of an area source emission inventory is generally
accomplished in five steps. These are:
1. Collection of data on national, state, and local area source
activity levels;
2. Collection of demographic, economic, and other data to be used to
apportion activity levels and emission factor parameters;
3. Apportionment of the areawide (typically a state) activity levels to
area sources (typically a county) using the appropriate apportioning
factors;
4. Calculation of estimated area source emissions by applying emission
factors to the apportioned area source activity levels; and
5. Converting the source information and emissions to a formal
formatted record and placing the formatted record into the file
(manual or automatic).
1-8
-------
AVAILABLE
RESOURCES
PLANNING
STATUS OF
EXISTING
INVENTORY
IDENTIFY INVENTORY
RESOLUTION AND
OBJECTIVES
DEFINE POINT
SOURCE/AREA
SOURCE CATEGORIES
IDENTIFY DATA
NEEDS, SOURCES,
AND METHODS
QUALITY
ASSURANCE/
DOCUMENTATION
DATA
COLLECTION
DATA HANDLING
SYSTEM FOR
COMPILATION, ANALYSIS
AND REPORTING
APPORTION
ACTIVITY LEVELS/
CALCULATE
EMISSIONS
REPORT
EMISSIONS
Figure 1-1. Activities for preparation of an inventory of area sources.
1-9
-------
It is essential to document data and procedures used in compiling the
inventory. Documentation will allow the agency to identify sources of raw
data and data handling methods used to estimate emissions. Documented
procedures must be followed when conducting quality assurance checks and when
updating the inventory as new data are added. Quality assurance checks of the
type described in Volume I, Chapter 2, of this series are necessary to ensure
that all area source data have been correctly entered into the file.
Full documentation requires the preparation of in-house manuals of
methods and procedures for use by agency personnel in developing and
maintaining the emission inventory. Adhering to agency procedures, to a large
degree, documents the inventory. The agency procedures should include
standard forms for recording calculations and data transformations and
conversions. Records of all communications that pertain to estimating
emissions; data conversions and calculations, including assumptions, emission
factors, and correlative parameters used; and copies of all reports should be
maintained in identified and accessible files for review, verification, and
update of the inventory.
A computerized inventory system is advantageous from a quality assurance
standpoint. A computer can perform calculations and conduct error checks much
faster than can be done manually. The computerized inventory is necessary if
dispersion models are to be utilized. The added complexity involved in
developing spatially and temporally resolved emission estimates will generally
be too time consuming to complete manually. The agency should give
consideration to using EPA's inventory data handling systems [National
Emissions Data System (NEDS) or the Emission Inventory System/Area Source
(EIS/AS)] or to developing a compatible system. Numerous summary routines and
various computer modeling programs have been designed to operate on these EPA
data bases.•*
The EIS/AS, developed by EPA represents the current state-of-the-art in
computerized systems. Figure 1-2 is an example load sheet used with the
EIS/AS system to input area source emissions information by geographical
area. Figure 1-3 is an EIS/AS load sheet used to enter emission data by
source category. Once all data is entered into the inventory file, the file
itself will serve as a permanent record of the area source emissions data. If
the inventory is compiled manually, the emission data sheets will serve as a
permanent record of the data.
The EIS/AS programs are modularized by function; i.e., each program
performs a complete function. When several functions are needed for a given
process (such as file maintenance), the separate programs that perform the
component functions are performed in a single procedure. For example, program
A maintains the emission factor file transactions, program B maintains the
emission factor file, and program C prints the emission factor file and
summary reports. Specific instructions for using the EIS/AS system can be
found in "The Emission Inventory/Area Source Users Guide."^
1-10
-------
u.
1
uf w
:I<
V!
8
8s
" VI
M
• ^
si
«r ^
£g
sp
li
S
£
i
^
g
ill! -
i- -
*
U r
(4^-O-UJ ~|
' -~ 1
P
U
<
1
w
3
|
i
w
§,
n »
|5
* S S
>•
*w S "
S — :
"^
j
e
S u
n
n
- -
)
r
-
.
"
-
_
-
-
1
j '
«
3
K
S
1
<
ii
il
R ~
-
-
•
.
-
-
-
-
M
N
s i
IL
e
S
0 £
tu
N
K
O
X
S _
" 5 -
gh
g
HI
R -•
(•ijfe
IS!
In
s « s
^i
< u
Bs °
gt
^
441
0
I
5 5
5 S!
s
R
^
^
w
£
S
J
_
•
»
i
:
V
s
n
-
*n
m
4
4
4
4
4
4
4
.
-
:
.
-
-
-
-
a S
S ^
E«GTH OF 11
MX. OR ARE*
-, -,
M03EUU
l"
K
y
5
S
S.
tn
ce
S :
N
EC
S :
N m r
M
1 i
g B f
E 5
§
z ;
i
S . 1!
m
h-
S ;
*n
IM
ec
tj
.»w M -
%
R »
If "°
4
R
4
n
4
i
S ^
1 "
4
4
^
:
-
<01— OZ
• •» !
1
il»
1
r
2 f
l« X ^
S
K x
»« 2 '
ft. « c
•N
S f
g .
f
1 IA
e <•
-
-
i
"
-
"
-
i
-
i
-
-
-
4U*~-Of
••ee
«3 •»
o
<
S ;
| *
K
m >
:l
ii
M
o
h
« X
9
tc
K
IM
S
<
%
u
u
u ,.
> S
>• (9
>
i
w
ac
«S
z
2
to*, uc ,
»ns: o; 3
'
* —
E a
-
-
:
_
:
_
:
?
-
s
-
-
S "
-
_
-
, -1
4
-
-
-
-
p
-1
-I
1
-\
I
_
-,
-i
•
c
o
•H
4J
CD
CO
C
cd
4-1
c
0
• H
•U
(X
CO
-------
K O
< 2
II
at
i—
3
0)
3
MS
•u
§
O
CM
I
0>
is
3
»•
J -
""^-l-
1-12
-------
EMISSION! INVENTORY SYSTEM/AREA SOURCE (Elt/AI)
AO
INCY
«.
1
j
COUNTY
1
MCR
r
COMPREHENSIVE DATA HANDLING SYSTEM (CDHS)
CATEGORY TRANSACTIONS
SUGAILOC
NM
10
CATIO
NSR
19
DMAO
NIR
i§
CATEGORY OtSCRIFTION VtAF
H> ••
1
M
1!
J
8
i i
I
t ! 1 ! 1 1 1 1 1 1 1
MN
t'
i
G
t
FEG
13
mt
ft
»
1
1
H
MONTHLY T
AW* ^AY
«
,
3
i
»
,
4
,
NRUF
JUN
31
1
IITM
JUL
33
1
ICEN1
AUO
39
NM
AGE FtR
IEF OCT NOV OIC OAY
i37 31 41 43 «»
I
iU
M
,
HOURLY THRUST?
1 9 10 11 12
t i i i i
CATEGORY
FROCESI RATE AUMTMNT
47
r
M
I
I*7
WKS
FIR
YR
4»
1
ERCEI
1]
i
THRUFUT
RATIO
»
1 1 A
ITAOI
14
11
CODE
a
MAXIMUM HOURLY
THRUFUT
34
u
NEDS A7 COMMENT
20
1
FOUUTANT
10
20
| 1 l l
EMISSION FACTOR
as
1 1 1 1 1 1 A 1 1
1 1 f i i i A i i
1 1 i 1 1 1 A 1
1 i i i A i
1 1 i 1 1 1 A 1 I
1 1 1 1 1 1 A 1 1
1 1 i 1 1 i A
i i i 1 i Ail
1 1 i l l l A i i
1 1 1 1 1 A 1
I 1 1 1 1 | A j
1 1 1 1 1 All
1 I 1 i 1 i A i i
0
N
F
11
s
G
»
|
37
FOUUTANT
SFCCIFIC DATA
31
1? 11 11
1
M
n
11
I
IM
GY.
OA1
re
FAOE
OF
vwn cooc
OCSCRtPTHM
••
NITRO
CONT
•1
, i i
U
i
*Blf
com
u
A
ASH
CONT
79
1 A
a
fl
«
IT
AJ
I
T
f
t
|
F?
HUT
CONTENT
73
?
;T
*
f
SOURCE OF INFORMATION NARRATIVE
n
1 l 1
74
NEOSA7
EMISSION
41
FOUUTANT NAME
99 M
C|
i
*j
?!
I
T*
j
|
M
J
1
I
?
7T
*
l
i
I
1 1 1 1 1 1
V
r?
«
•
3
7»
5
1
1
1
1
f
1
It
1
1
ZO—
•0
Figure 1-3. Example area source load sheet - category transactions.
1-13
-------
The conduct of the activities depicted in Figure 1-1 is an iterative
one. The output of the data handling system, whether manual or computerized,
must be examined by the agency to ensure that the outputs are sound and
consistent with state and local conditions. Serious discrepancies or
questionable outputs will require the agency to re-examine the data sources
and/or methods of apportioning and calculating emissions.
In general, emission inventory methods that use locally available data
(such as survey questionnaires or data from local distributors) result in the
most accurate emission estimates. The five-step procedure previously outlined
is usually required because adequate source data are often not available for
counties or smaller geographic units. Thus, for many source categories,
areawide totals, often state totals, must be used to apportion totals to
counties. Once county totals are obtained, similar procedures can then be
used to apportion these totals to grids, if desired.
The use of statistical data (e.g., population) as apportioning factors
presumes a relationship between the available data and the desired area source
pollutant. For some area source categories, reasonably accurate predictions
of area source quantities can be obtained using this method. For other area
source categories, it is difficult to obtain any literature data that can be
correlated with emissions. New data must be developed or existing data
modified to provide a better indicator of area source activity levels. In
addition, existing emission factors for many area source categories are based
on limited and often site-specific data; e.g., silt content of soils and
roadways. Thus, the development of an accurate inventory of area sources will
require the use of many sources of information, and the application of sound
judgment by local agency personnel in their selection of apportioning methods
and emission factors.
1.5 PURPOSE AND ORGANIZATION OF THE VOLUME
The purpose of this volume is to assist the user in identifying area
source categories and relevant sources of data that can be used to estimate
emissions from these categories. Methods for the development of the inventory
of area sources are provided in Chapters 2, 3, 4, and 5, respectively, for the
following major source categories:
Combustion Sources,
Solid Waste Incineration and Open Burning Sources,
Fugitive Dust Sources, and
Volatile Organic Compound (VOC) Sources.
In each chapter, the data requirements for establishing emission levels
are presented along with the available data sources. Validation methods and
cross checks which are available to assess data accuracy and to establish the
reliability of the inventory are also delineated. Chapter 6 deals with the
1-14
-------
presentation of the inventory of area source emissions. Volume I of this
series and References such as Nos. 3, 6, and 7 should be consulted for further
information concerning planning, preparing and documenting the emission
inventory.
References for Chapter 1.0
1. Procedures for the Preparation of Emission Inventories for Volatile
Organic Compounds, Volume I, First Edition, EPA-450/2-77-028, U.S.
Environmental Protection Agency, Research Triangle Park, NC, December
1977.
2. AEROS Manual Series, Volume I, AEROS Overview, EPA 450/2-76-001, U.S.
Environmental Protection Agency, Research Triangle Park, NC, February
1976.
3. Procedures for the Preparation of Emission Inventories for Volatile
Organic Compounds, Volume I, Second Edition, EPA-450/2-77-028, U.S.
Environmental Protection Agency, Research Triangle Park, NC, September
1980.
4. 1977 National Emissions Report, EPA-450/1-80-005, U.S. Environmental
Protection Agency, Research Triangle Park, NC, March 1980.
5. The Emission Inventory System/Area Source User's Guide, EPA-450/4-80-009,
U.S. Environmental Protection Agency, Research Triangle Park, NC,
May 1980.
6. Development of the Area Source Emission Inventory for the 1982 Ozone
State Implementation Plan for the Chicago Metropolitan Region of Illinois
and Indiana, Contract No. 81C-279, Northeastern Illinois Planning
Commission, Chicago, IL, 1981.
7. Final Emission Inventory Requirements for 1982 Ozone State Implementation
Plans, EPA 450/4-80-016, U.S. Environmental Protection Agency, Research
Triangle Park, NC, December 1980.
1-15
-------
2.0 COMBUSTION SOURCES
Stationary fuel combustion sources that emit less than the minimum level
of pollutants prescribed for point sources are included in the inventory of
emissions from area sources. External combustion sources used for space
heating and other functions, and internal combustion turbines and
reciprocating engines used for the pumping and compression of fluids and
electricity generation, are included in this major area source category. An
emission rate of less than 100 tons per year of any criteria pollutant is
characteristic of uncontrolled combustion systems which are smaller than the
following thermal input capacities.1
Bituminous Coal 4 x 106 Btu/hr
Residual Oil 13 x 106 Btu/hr
Distillate Oil 55 x 106 Btu/hr
Natural Gas 110 x 106 Btu/hr
Internal Combustion 10 x 106 Btu/hr
These maximum area source capacities vary with type of combustion unit, fuel,
ash and sulfur content, operating hours and load. The value for internal
combustion units is subject to the greatest uncertainty due to the pronounced
effect of engine type (i.e., turbine or reciprocating engine), operating
parameters, and fuel on emissions of nitrogen oxides, carbon monoxide and
hydrocarbons. Lead emissions from area combustion sources are not
significant, amounting to about 100 tons per year. This is less than
1 percent of estimated lead emissions from all stationary sources.
2.1 EXTERNAL COMBUSTION SOURCES
All criteria pollutants are emitted during fuel combustion. Each source
may emit only small quantities of pollutants but, because of their great
number, their collective contribution can be significant. Therefore, it is
necessary to obtain an accurate estimate of this collective contribution to
total emissions.
2.1.1 EXTERNAL COMBUSTION SOURCE CATEGORIES
External combustion sources are grouped by fuel into the following three
categories, representing the use of the fuel burning equipment.-^
Residential—Structures containing fewer than 20 dwelling units.
Commercial/Institutional—Establishments, not classified as point
sources, engaging in retail and wholesale trade, schools, hospitals,
government facilities and apartment complexes with 20 or more dwelling
2-1
-------
units. The commercial/institutional sector covers all establishments
defined by Standard Industrial Classification (SIC)^ groups 50 through
99.
Industrial—All manufacturing establishments not classified as point
sources. Included are those establishments defined by SIC groups 20
through 39.
Collectively, these three use categories account for the predominance of
nonpoint combustion source emissions.-^ The breakdown of fuel use into three
categories provides the basis for apportioning emissions to county and
subcounty levels and is useful for the formulation of strategies to achieve
air quality goals.
2.1.2 FUEL USE
Area source emissions from the three use categories are reported for each
major fuel. The subdivision by fuel, in addition to providing valuable
information to the agency, is needed to relate activity levels to AP-42
emission f actors.-* The seven major fuels that are used by area combustion
sources are:
Anthracite Coal—Anthracite coal is mined almost exclusively in
Pennsylvania. It is used mainly by residential sources in states that
are within economical shipping distance of Pennsylvania.
Bituminous Coal—Bituminous coal, including sub-bituminous and lignite
coals, is available in most areas of the country. It is used primarily
by the commercial/institutional and industrial source categories.
Distillate Oil—Fuel oil grades 1, 2 and 4 and diesel fuel and kerosene
are considered distillate type oils. Residential and commercial/
institutional sources are the largest consumers.
Residual Oil—Residual oils include fuel oil grades 5 and 6. These fuel
grades are not used by residential sources.
Natural Gas—Natural gas is used by all three source categories.
Liquified Petroleum Gas (LPG)—LPG may be used in some areas by all
categories.
Wood—Wood is primarily a residential fuel, although it may be used by
all source categories.
In addition to the above major fuels, some coke and process gas may be used by
area sources. Although area source usage of these fuels is low, activity
levels should be determined by the agency.
2-2
-------
2.1.3 DATA REQUIREMENTS AND SOURCES
Emissions from external combustion area sources must be determined at che
spatial and temporal levels of resolution required by the agency. Fuel used
in the inventory area by the source category, minus the fuel used by point
sources within the inventory area, is multiplied by the appropriate emission
factors in AP-42 to obtain criteria pollutant emissions before control.
2.1.3.1 Activity Levels
Fuel use data should be obtained from local sources of information if
possible. Many state and local environmental agencies charged with compiling
inventories of area sources use data from local fuel dealers, agency permit
registrations, and other state and local agencies involved in such functions
as energy policy, commerce, taxation and land use planning. Local natural gas
suppliers are generally reliable sources of usable information. Data obtained
from coal, wood and oil distributors are generally less reliable; distributors
are much more numerous and care must be exercised to insure that all dealers
are included. Activity levels derived from dealers must also take into
account shipments into and out of the area.
If local data sources are inadequate then literature sources must be
used. Table 2-1 lists the literature sources which can be used to determine
the factors necessary for estimating activity levels. Department of Energy
(DOE) reports provide accurate state fuel use totals for oil, natural gas, and
LPG. Consumption of bituminous coal and lignite is reported for most states.
Information regarding anthracite shipments to some states is also available
from DOE and can be used to estimate state anthracite fuel use.
The DOE reporting techniques vary for each fuel, and adjustments of the
reported values are required to allocate state fuel totals to the residential,
commercial/institutional, and industrial categories. Accepted techniques for
assigning fuel use to categories are those used by the U.S. EPA in the
National Emissions Data System (NEDS). Most states that do not rely on local
information sources use these techniques, which are based on correlative
relationships among demographic, socioeconomic, and local climatological data
and fuel usage. Department of Commerce Publications are the primary sources
of correlative information. Much of the data are updated annually. Other
data must be updated by the agency using state or local sources of information
or information from fuel trade associations.
2.1.3.2 Spatial Resolution
Apportionment of state totals to county or subcounty levels by NADB
relies on techniques and correlative relationships which are similar to those
used for allocating fuel use to source categories. Combustion source data
compiled at the county level are generally sufficient for most applications of
this inventory. However, certain inventory applications; e.g., dispersion
modeling, will require finer spatial resolution in which counties must be
subdivided into grid squares. Instructions for apportioning fuel use to grid
squares are given in Section 2.1.6.
2-3
-------
CO
£•3
rJ
1
O
H
£""•
M
M
S
H
CO
M
p>
s
CO
w
CJ
B
c^
CO
^4
H
P
I—I
^J
o
M
H
l_^
%
S
t"f
CO
•
*-?
CN
W
M
**H
tH
"
CO
B
CU
O
CJ
CU
CJ
B
V •
rH O
01 tZ
U-I
(S
4)
CJ
3
O
CO
-^^
§
• H
4->
CO
e
o
U-4
rH
rH 4-J
rH C
CO CU
rH Cl)
rH 4} CJ
O U-I r-l
H j i^i ^
•rH O
4-1 73 CO
B
4) P*, CU
rH rH 0)
CU 4-1 rH
U-i 43 J3
U-I 60 4J
•H -H
•V rH 01
CO JC
O> 4-1
rH U-I
co O O
CO CU
B CO rH
O 3 41
• H 3
4-> 00 U-I
CO B
O -r-f 4)
•H rH 4->
U-I .H CO
•H 3 CJ
tn ty o
CO CU rH
CO rH rH
rH CO
U CO
3 0
oo si 4-1
6 4J
•H CO
4-1 -> 73
rH CO O
O rH JS
CX 4) 4J
0) 3 CU
OS UH B
v _ -
^o r** oo
41
B
JC
4-1
B W
< O
M -r-ITS
W 4-1 C
--- CX CO
U 3
S3 co
co co
CU B O
B 0
<-* 4) CJ 0
rH CO 3
CO O 73 4)
3 rH B rH
B CU cfl O
C X rH
< B 4-1
^ 73 O CU
E -H PH
CO Cfl 4-1
4J CJ 73
41 rH rH 3 01
4J O -H 73 -H
cfl a o o u-i
CO Q4 rH OH 3
cu cy
>-, CO 3 CO • r-l
ft 4-1 fa CO rJ
CO CJ
0) Q u-i u-i
CO O rH O
D X to
00 CO rH CO
rH rH 0) 3 4)
4) 41 rH 4-1 rH
3 B CO CO CO
rjt4 [IJ CO !25 CO
•
ca
H
U
O
oo
4)
4J
CO
O
-.—.^
ON O
I—I
CU
CU 4J
4-1 -i-l
•H CJ
B CO
00 rH
•H x:
rJ 4J
c
73 H^
CO CO
•H
co B
O ^
0 >
B «-i
•H >-,
B to
2 g
• H 41
« OH
1 1
t— 1 i— I
cfl eg
3O
CJ
rH
CO
3
B
B
cfl
CJ
M
C/3
^,
JQ
4-1
B
B
^
o
,—4
a.
S
4)
X
rH
0
00
CU
4-1
co .
•*
rH
CO
O
4J
CO
• H
4-1
CO
4-1
CO
CO
3 ca
CD 0)
cu co
CJ 4J
CO
U-I
0 73
32
Cfl -H
§£
ca
41
o
B
CU
M
41
U-4
41
4J
CJ
CO
4-J
B
O
O
. *.
^
^4
0
00
41
4-1
CO
u
41
O
rH
3
O •
ca ca
4)
-a co
73
cu a.
co 3
rH
rH 0
CU U-4
3
CN
rH
ca
|— ^
rH
01
3
^
B
cu
4-1
CO
co1
tfl
to
O cu
ca
co S
B
O rH
•H CU
to 3
ca fa
• H
B --1
W cfl
•r-l
rH U 4-1
Cfl I-l C
BO CU
00. 73
•H 4) 'H
4-1 PC CO
CO 41
Z Cd
B
O
4J
CJ CO
B 4-1
3 to
U-I 73
r*N * **
£> s-^
00
4> B
CO 'H
3 .y
o
rH 0
01 CJ
3
U^ 73
B
73 CO
tO M
CU
ca 4-1
O cfl
4J
ca 4-1
•rH 0
rH JB
CU
4J - 73
CJ 00 01
cfl C -M
rH -H CO
Cfl 4J 73
jc to a,
O CU 3
.C
00 4)
6 -J3
•r-l •
CO 00 4J
3 . to
O cu 3
33 ^ B
_. •— - !• •
CO ^>
rH rH
00
4J B
O ca
a. 3
rS °
73 73
0> 41
O rH
B -H
td ca
> 4J
35
oo oo
B C
•r-l -H
ca co
3 3
ss s
•H
U-t U-I 4-1
0 0 to
•H
CO CO r-l
3 3 cu
CO CO 4J
B G o
4) 4) <0
0 O rH
CO
O O .C
f*~ r** C?
rH rH
•
CO
4-1
CO
73
X
CO
1
0)
CU
rH
00
5
IO
r~(
r*
4J
•H
J
S^
(Q
g
£3
3
W
i— t
cd
D
C
-2
co"
4-1
<§
rH
Cfl
U to
•H 4J
oo to
0 Q
rH
O 4>
4J >
CO -H
B 4-1
•H CO
cj to
rH Q
cfl O
CJ CJ
3
41
rH
^
CO
rH
• H
CO
r>
CO
1
ca
u
• H
4-1
CO
• H
rH
CU
4J
u
CO
rH
CO
CJ
rH
CU
3
U-4
•^^
00
B
•rH
CO
3
O
f. •
U-I i— 1
O rH
CO
CU 3
4J B
CO B
73 tO
a
^MM^^H^
V40 ^
rH rH
ca
cfl
CJ
B
0 B
•H CO
4-1 CJ
Cfl -H
•H rH
U 41
0 g
CO <
ca
^
ca cu
O VH
3
B co
to
CJ 00
• H B
r-l -H
4) 4-1
g Cfl C
< 4) O
3. -rH
4-1
CO 4) CO
4-1 W • r-l
O 3 U
cO O O
f»< X to
co ca •<
CO co
O O
VH
CU
jO
O
4-1
U
O
B
•H
^
rH
rH
cfl
3
B
B
CO
CU
1— 1
rO
cfl
rH
• r-l
tO
^
CO
1
1
CU
ca
3
rH
CU
3
U-I
U-I
0
0)
4J
Cfl
-o
(X
00
rH
CO
B
O
•H
4J
CO
O
• H
rH
rO
3
OH
l^H
4-1
CO
3
C
M
„
4J
CO
41
33
rH
•r-l
O
73
B
CO
rH
•rl
O
rH
0)
t2
•
CO
O.
3
O
rH
00
CJ
M
CO
U-4 CJ
0 M
CO
B
O >,
•H Ja
4-1
CO 4-1
U B
•H 01
LL j Cl
•H g,
4J 0
C rH
CU OH
M [|
•^ ON
rH
CU
CO
!=>
i— i
cu
[X4
1— 1
CO
• H
rH
4-1
CO
3
B
M
73
C
to
rH
Cfl
B
O
4-1
3
4-1
• H
4-1
CO
M
•>^.
rH
rcia
41
I
8
CN
r^.
ON
rH
A
rH
CO
3
B
Cfl
jg
B
O ^N
•H i— 1
4-1 Cfl
to 3
0 B
•H C
IM
-------
2.1.3.3 Temporal Resolution
A comprehensive inventory of area combustion sources is designed to
estimate emissions for any time period. Most inventories are planned to
provide annual data. In preparing more detailed temporal inventories, it is
generally assumed that the temporal distribution of residential, commercial/
institutional, and industrial fuel use (for area source space heating) is
identical. The agency should verify this assumption by obtaining hourly
natural gas flow data for various customer classifications from local gas
dealers. Natural gas consumption data adjusted for nonheating uses can be
correlated with local temperature data to show the relationship between
outdoor temperature and fuel use for space heating. This relationship can be
applied to all fuel types to estimate seasonal consumption for space heating.
Monthly billing records, obtained from local fuel dealers, will also provide
an estimate of monthly and seasonal fuel consumption patterns.
2.1.3.4 Emission Factors
Criteria pollutant emission factors can be found in AP-42 and its
supplements for all fuels. The AP-42 emission factor parameters (sulfur
content of fuel oil and ash and sulfur content of coal) needed for calculation
of particulate and sulfur oxide emissions are usually available at the state
agency or from local data sources. Information can be obtained from such
sources as permit registrations, local fuel dealers or, if necessary, DOE data
for states. Local point source information or agency regulations can also be
used. It is usually acceptable to assume that the sulfur and ash contents of
a fuel used within a county are similar for the residential, commercial/
institutional, and industrial source categories.
Lead emissions from area source combustion categories will be negligible
for normal fuels. >^0 ^e use of usecj automotive lubricating oils for space
heating, however, may result in locally significant lead emissions due to the
generally high lead content of such
For coal— fired sources some care must be exercised by the agency in
selecting furnace types and their associated AP-42 emission factors for use in
calculating emissions. Pulverized units, cyclones and spreader stokers,
because of their size, would almost invariably be reported as point sources.
Most residential units would be hand-fired overfeed stokers. Under-fired
stokers account for over 80 percent of commercial/institutional units of less
than 10 x 10^ Btu/hr thermal input. However, some overfeed and other stoker
types could be used. The particulate emission factors for bituminous
underfeed and overfeed stokers are 2A (A = ash content in percent) and 5A,
respectively. Significant error in the combustion source particulate emission
estimate could result in locations burning large amounts of coal, if overfeed
stokers predominate, and the emission factor for underfeed stokers is used.
2-5
-------
2.1.4 DETERMINATION OF STATE FUEL USE BY SOURCE CATEGORY
As noted above, accurate state fuel consumption figures are available in
most instances from DOE publications. These state totals include fuel used by
point sources. Nonpoint or area source fuel consumption must be allocated to
the three area source categories and, subsequently, to the geographical area
of the inventory. The following is a description of the procedures used by
the NADB to allocate DOE state fuel use data to the three source categories.
The procedure is diagrammed in Figure 2-1 for fuel oil.
2.1.4.1 Residential
Residential fuel use is calculated for each fuel type using the following
empirical equations. The correlative relationships and their constants shown
below were developed in the early 1970 's and, because of present day emphasis
on fuel conservation, may tend to overestimate residential fuel use.
Distillate Oil (gal/yr) —
...12MD » 30.41R -
Residual Oil (gal/yr)—
FRO = 0 (2-2)
Natural Gas (therms*/yr)—
/S \0.588
Fw = 47.5 x A x D °*367 x(r~) x R° 25 (2-3)
NG \WNG/
LPG (therms/yr)—
FLPG = °76 + °'209D) SLPG + HC
Coal (tons/yr)—
_ 1000\
= 0.003874 e' D I (2-5)
*1 therm = 105 Btu.
2-6
-------
STATEWIDE FUEL
OIL FOR HEATING
(REF. 6)
EQUATIONS (2-1) AND (2-2)
STATEWIDE
RESIDENTIAL
FUEL
USE
EQUATION (2-7)
STATEWIDE
FUEL OIL
FOR C/l*
HEATING
STATEWIDE
FUEL OIL FOR
INDUSTRIAL
HEATING
STATEWIDE
FUEL OIL FOR
INDUSTRIAL USE
(REF. 6)
STATEWIDE FUEL
OIL FOR OIL CO.
USE (REF. 6)
C/l
POINT SOURCE
FUEL USE
INDUSTRIAL
POINT SOURCE
FUEL USE
STATEWIDE
FUEL OIL
FOR MILITARY
USE (REF. 6)
STATEWIDE
INDUSTRIAL AREA
SOURCE FUEL USE
STATEWIDE
C/l AREA
SOURCE FUEL OIL
*C/I = COMMERCIAL/INSTITUTIONAL
Figure 2-1. Procedure for determination of state area source fuel
oil use by source category.
2-7
-------
Wood (tons/yr)—
FW = 0.0017 x Sw x D x (2-6)
where F = fuel use, in units shown;
A = total number of natural gas customers, obtained from American
Gas Association*' or local suppliers;
D = degree-days, obtained from Reference 15;*
HC = therms of LPG used for cooking, regional average therms
obtained from the American Gas Association-*-" or
y = therms of LPG used for water heating, regional average therms
obtained from the American Gas Association*" or NADB^;
R = number of rooms, obtained from Reference 14;
S = number of housing units using fuel for space heating, obtained
from Reference 14;
= number of housing units using fuel for water heating; and
= the larger of the number of housing units using natural gas
for water heating or cooking, obtained from Reference 14 and 17.
Updating of the Census of Housing data base is necessary to determine S,
R, W, and A for the year of the inventory. Information concerning housing
characteristics, including the net increase in combustion units, can be
obtained from local sources or trade associations and journals. " A
sharp rise in the use of coal and wood units for apace heating in some
locations should be monitored closely by agencies in those locations.
It will be necessary in many areas to determine residential consumption
of both anthracite and bituminous coals. To do so, compare the calculated
residential consumption of coal to anthracite deliveries minus all anthracite
point source use. If the calculated consumption is greater than the available
area source anthracite the difference is assigned to bituminous. If
calculated consumption is less than the available anthracite the remaining
anthracite is assigned to the commercial/institutional and industrial sectors.
*Each degree of declination below 65°F in mean outdoor temperature, averaged
over a 24-hour period, is a degree-day.
2-8
-------
2.1.4.2 Commercial/Institutional
The procedure for determining state area source fuel consumption by the
commercial/institutional source category is to (1) obtain fuel use data from
DOE publications, (2) subtract calculated residential fuel use from DOE total,
(3) allocate a fraction of the remaining fuel to the commercial/institutional
category, and (4) subtract commercial/institutional point source fuel use.
Because of DOE reporting methods, allocation procedures will differ depending
upon the fuel used. The procedure for fuel oil is shown in Figure 2-1.
Specific step-by-step procedures for each major fuel are presented below.
Fuel Oil—
1. Calculate residential fuel oil consumption for state using Equations
(2-1) and (2-2).
2. Subtract residential fuel oil from fuel used for heating in
Reference 6 to obtain commercial/institutional and industrial fuel
total.
3. Allocate remaining fuel oil to the category using the following
expression:
F = /F + F \ State employment in SIC groups 50-99 d-7)
C/I 1 C/I Ind) State employment in SIC groups 20-39 and 50-99
4. Subtract point source commercial/institutional fuel oil.
Natural Gas—
1. Allocate commercial/institutional and industrial state fuel use
total provided in Reference 7 to their respective categories using
Equation (2-7).
2. Subtract point source commercial/institutional natural gas fuel use
from allocated commercial/institutional fuel above to obtain state
area source fuel use.
LPG—
1. Subtract calculated residential fuel use from residential and
commercial/institutional fuel use total provided in Reference 8 to
obtain state commercial/institutional fuel use.
2. Subtract point source commercial/institutional LPG fuel use to
obtain state area source fuel use.
2-9
-------
Bituminous Coal—
1. Assign bituminous coal from "retail sales category" in Reference 9
to the residential category if needed to make up the difference
between calculated coal consumption (Equation 2-5) and available
area source anthracite.
2. The remaining bituminous fuel used for "retail sales" is assigned to
the commercial/institutional category.
3. Subtract point source commercial/institutional fuel use to obtain
state area source bituminous coal.
Anthracite Coal—
1. Allocate available anthracite (total anthracite minus residential
area source and point source anthracite used by utilities) to the
commercial/institutional category using Equation (2-7).
2. Subtract point source commercial/institutional fuel use from result
above to obtain area source fuel use.
Wood—
Wood is not generally used by the commercial/institutional category
unless there is evidence at the local agency level to indicate
otherwise.
2.1.4.3 Industrial
State area source industrial fuel use is determined as follows for the
major fuels.
Fuel Oil—
Industrial fuel used for heating (total fuel oil used for heating
minus the fuel used for residential and commercial/institutional
heating as determined above), plus fuel oil for industrial and oil
company use,* from Reference 6, represents the total industrial fuel
oil use within the state (see Figure 2-1). Subtract point source
fuel use to obtain state area source industrial fuel consumption.
*The agency should note that oil companies burn a substantial quantity of fuel
oil in oil tank heaters to control residual oil viscosity. Whether or not
these sources will be included in the area source inventory depends on the
source size and the point/area source size cut-off set by the agency.
2-10
-------
Natural Gas—
State industrial area source natural gas use is obtained by
subtraction of the sum of the total commercial/institutional gas use
and industrial point source gas use from the combined commercial/
institutional and industrial total given in Reference 7.
LPG--
State industrial area source LPG use is the industrial use total
given in Reference 8 minus LPG used by industrial point sources.
Bituminous Coal—
State industrial fuel use, plus coal used by coke plants, are
provided in Reference 9. Point source use should be subtracted from
the total to obtain the state area source total for the industrial
category.
Anthracite Coal—
Anthracite coal use by the industrial source category is the
difference between the total fuel available for allocation minus the
fuel used by the commercial/institutional category, as calculated by
Equation 2-7. Subtract industrial point source use to obtain area
source use by the industrial category.
Wood--
Industrial area source wood consumption is considered to be
negligible. However, some wood-related industries will burn wood
waste. A survey of potential sources is necessary in certain
locations.
2.1.5 DETERMINATION OF COUNTY FUEL USE BY SOURCE CATEGORY
If fuel use data for counties are not available at the local level the
same general procedures described above can be used to calculate county totals
or to apportion state fuel use to the county. The methods described below are
adequate for almost all purposes of the inventory and are much simpler to
apply than the procedures now used by NADB.
2.1.5.1 Residential
Residential fuel use is calculated for each county and fuel using
Equations (2-1) through (2-6) shown in Section 2.1.4.1. It is worth noting
that the equations may tend to overestimate residential fuel consumption
because of fuel conservation practices and, thus, underestimate fuel use by
the commercial/institutional and industrial categories.
2-11
-------
2.1.5.2 Commercial/Institutional
The NADB procedures for estimating fuel consumption by the
commercial/institutional category are complex. They are based on correlative
relationships between employment and fuel use for five subcategories;
hospitals, hotels, laundries, schools and universities. Because fuel use by
the commercial/institutional category is less than that for the residential
and industrial categories, and because the five categories account for only a
modest percentage of total commercial/institutional fuel use, the NADB
procedures are not recommended, except for the most detailed inventory. To
determine county fuel use, apportion state commercial/institutional fuel to
the county by population using the following expression:
county state / n _. ,. \
I population of county i /0 O
area source = area source I * r , -. ^ ^-| (2-8
,. , .. , \ population of state /
fuel use fuel use \ «- r /
The use of Equation (2-8) for all fuels consumed within the state assumes
that the distribution of fuel use is similar for each county and the state as
a whole. If the agency has reason to question this assumption, a procedure
which assumes that residential fuel distribution is equivalent to that of the
commercial/institution category can be followed. In this case, county
commercial/institutional fuel use for each fuel is calculated as follows:
/residential county fuel use\ ,„ „,.
area source = area source I r-, :—: ^7—= I (2-9)
\residential state fuel use /
county state
»^ea source = area soui^ • . , . , ,.
f -. c , \ residential state fuel use
ruel use fuel use \
2.1.5.3 Industrial
The following steps should be followed to apportion state industrial fuel
use to each county.
1. Subtract county industrial (SIC 20 to 39) point source employment
from total county industrial employment. Employment data are found
in Reference 19.
2. Subtract state industrial point source employment from total state
industrial employment (Reference 19).
3. Calculate county industrial area source fuel use as follows:
County area source
industrial fuel use
state industrial area /county area source industrial employment\ /o
source fuel use \ state area source industrial employment J
2-12
-------
The NADB procedures are similar, but rely on adjustment of employment
figures within each two digit SIC, using point source employment data and fuel
intensity factors developed for each two-digit SIC. The procedures, while
useful for estimating total industrial fuel consumption, are of questionable
merit for industrial area sources.
2.1.6 APPORTIONING FUEL CONSUMPTION TO SUBCOUNTY LEVELS
Techniques for apportioning countywide fuel consumption to smaller areas,
thus showing more clearly the areas of high emission density and their origin,
are similar to those discussed above for apportioning state totals to the
county level. Fuel consumption, and subsequently emissions, are apportioned
to a map of the study area on which grids are superimposed, as shown in Figure
2-2. The UTM Coordinate System is used to define the grid area and its
boundaries. The required level of resolution of the inventory will determine
grid size. Usually, as shown in Figure 2-2, the grid sizes used will be
smallest in urban areas and largest in rural areas, thus providing greater
emphasis to areas of high population density, while limiting the number of
grids and the attendant level of effort to a practical limit.
2.1.6.1 Apportioning Population to Grids
As a first step in the apportioning of fuel consumption, information on
population and housing distribution in counties by census tract is obtained
from the U.S. Bureau of Census. Contact with local planning agencies or the
Chamber of Commerce will usually be necessary to ensure that information is
current and complete.
Estimates of population within each grid are made using census tract maps
suitably adjusted to reflect current conditions. The assumption is made that
population is uniformly distributed over each tract. The populations for each
grid is computed as follows:
1. Using an overlay of the grid system, estimate the fraction of a
census tract in a grid zone.
2. Multiply this fraction by the total population of the census tract
to obtain census tract population within the grid.
3. Sum the contribution of each census tract within the grid to obtain
total grid population.
After apportioning, the population in all grids are totaled to ensure
that the sum is identical, or nearly so, to the total population of all census
tracts within the study area.
2.1.6.2 Apportioning Fuel Consumption
For residential fuel use, assume housing distribution is similar to the
population distribution previously determined. The type of fuel used by
2-13
-------
460°00 470000 4)0000
440
.V
1
j
i
000 /
/
000
'
,'
I
^_ /
)
V
\
CUVIIAHO CO
i\
SHELBY
NORTH CAROLINA
SOUTH CAROLINA
f
/
1
I
T
c.
I
ir
lJ3S
^4p
i \
' HICKORY
(A1AWIA
1
. i me oi «
%\ C»$t(
'l GA1
V,
"1
1
' f
I
roil
'»
i*
r
*~\
\
i
*
0
(
:o
CO
i
TONIA
O
1
-^_
l(
/
/
\
"n -
'S
^
500
*
\
f
/
/'
V_j
X
(0
"
ROCK
14
ll
-s».
N
\
\
'^-^
•
\
* \
t 1
\
1 >
J „
;
,*' _ /
\-s
ooo
p»woooo
I
j
i
1 540000
L^ -
ION«R CO
/
l« 10
1
" sf
INNAPOl IS^
" \ If*
V. I
• u
i " ^\
\ T*
\
CHARLOTTE "
/
" /
/
UNION
If
*'
^LANCASTER
UHtkMtl to
• ?
7700°°°
s s^o ooo
Is
SA ISBURY
it
•»
lAIAMUi CO
1
CONCORD
ft 1
J
^-(
n-^- ^ ^ '
"
(0
• i
IN
\
\
U
•
5100
*
^
\
^
. -
J
39 to 000
30 w) 000
I
i
3*70 000
|
1
1
3d SO 000
18 ID 000
..''
JfllO000 1
13950000
Figure 2-2. Grid coordinate system example.
2-14
-------
housing within a grid is assumed to be identical to the county distribution of
fuel use. The fuel is allocated to the grid by multiplying county fuel use by
the ratio of grid population to county population.
For commercial/institutional fuel use, the same procedure as that used
for residential fuel can be applied. If local planning agencies compile
commercial/institutional employment data on a subcounty level, fuel can be
allocated to the grid by multiplying county commercial/institutional fuel use
by the ratio of grid commercial/institutional employment to county
commercial/institutional employment. If employment data are not available,
zoning maps, obtained from local planning agencies, can be used. These maps
indicate the total land area utilized for a given purpose (e.g., residential,
commercial/institutional, industrial). To use the zoning map, the agency grid
must be plotted to the same scale as the zoning map. The grid is then
overlayed onto the zoning map so that the total area zoned for
commercial/institutional structures within each grid square can be visually
estimated. Fuel use is then allocated to the grid by multiplying commercial/
institutional county fuel use by the ratio of grid commercial/institutional
zoned area to county commercial/institutional zoned area.
Local zoning maps should be used for apportioning industrial fuel. The
agency grid (adjusted to the zoning map scale) is overlayed onto the zoning map
and the total area of industrial zoning in each grid square is determined.
Fuel is apportioned to the grid by multiplying industrial county fuel use by
the ratio of grid industrial zoned area to county industrial zoned area.
2.1.7 CALCULATING EMISSIONS
Emissions of criteria pollutants are estimated by multiplying the
emission factors given in AP-42 by fuel consumption. Emission factor
parameters (ash content of coal and the sulfur content of all fuels) must be
known by the agency in order to use the AP-42 emission factors. The use of
average ash and sulfur content for fuels used within the county is adequate.
This information should be available within the agency, if not, local fuel
dealers or DOE publications should be consulted.
As noted previously, combustion units with heat inputs greater than a
certain size will be in the point source inventory. Coal-fired units of
pulverized, cyclone or spreader stoker design are almost invariably included
in the point source inventory. As a guide to the agency, over 80 percent of
commercial size stokers are of underfeed design. This is probably true also
for the smaller size industrial furnaces. Most coal-fired residential units
will be hand-fired, although new units are generally equipped with overfeed
stokers.
2.1.8 SAMPLE CALCULATIONS
To assist agency personnel in applying the methods described above for
estimating emissions from area external combustion sources two sample
calculations are given below.
2-15
-------
EXAMPLE 1. Allocation of fuel use to categories and counties
Given; Data for year of inventory
Population: County—300,000; State—3,000,000
Dwelling units (DU) in county number 100,000. Of these: 10,000 DU
use coal for space heating
40,000 DU use oil for space heating (20,000 use oil for water
heating)
35,000 DU use gas for space heating (30,000 use gas for cooking,
20,000 for water heating)
15,000 DU use electricity for space heating
Median unit size is 5.5 rooms per unit
Employment in SIC Groups 20-39:
County—20,000; State—300,000
Employment in SIC Groups 50-99:
County—30,000; State-200,000
DOE State fuel oil use data (Reference 6)
Distillate oil used for heating: 15,000,000 barrels or 630,000,000
gallons
Residual oil used for heating: 30,000,000 barrels or 1,260,000,000
gallons
Distillate oil for industrial and oil company use: 4,000,000
barrels or 168,000,000 gallons
Residual oil for industrial and oil company use: 25,000,000 barrels
or 1,050,000,000 gallons
Distillate oil for military use: 1,000,000 barrels or 42,000,000
gallons
Residual oil for military use: 500,000 barrels or 21,000,000 gallons
DOE state natural gas use data (Reference 7)
Natural gas used by the residential category: 72,000 x 10°
Natural gas used by the commercial and industrial categories:
150,000 x 106 ft3
DOE state bituminous coal use data (Reference 9)
Bituminous coal for retail sales: 330,000 tons
Bituminous coal for industrial: 480,000 tons
DOE state anthracite shipments data (Reference 10)
Anthracite shipments to state: 150,000 tons
Annual degree days: 5000
2-16
-------
Calculations:
Step I Calculate county residential fuel consumption using Equations 2-1,
2-2, 2-3, and 2-5.
A. Distillate oil (Equation 2-1)
/O.01288 (5000 degree-days) + 30.41 (5.5 rooms/DU) - 79.54\
\ 0.14 /
40,000 + 250 (20,000 DU using oil for water heating) =
43,461,000 + 5,000,000 = 48,461,000 gallons
B. Residual oil (Equation 2-2)
Residual oil = 0 for the residential category
C. Natural gas (Equation 2-3)
47.5 (35,000 DU) x (5000 degree-days)0*367 x
35.000 DU \0-588 ,x0.125
30,000 DU for cooking/ X ° '
= 1,662,500 x 22.8 x 1.09 x 1.24 = 51,232,398 therms or
5,123,240 x 106 Btu or 5.12 x 109 ft3
D. Coal (Equation 2-5)
•7 c.i 10°0
7 .64 -
0.00387 x 10,000 DU x e \ 50°° Degree-days
= 38.7 x 1702 = 65,896 tons of coal
Step II Sum residential fuel totals for all counties to obtain state
residential fuel consumption. Hypothetical results are:
Distillate Oil—500,000,000 gallons
Residual Oil—0 gallons
2-17
-------
Natural Gas—76 x 109 ft3
Coal—300,000 tons
Step III Determine state commercial/institutional and industrial area source
fuel consumption
A. Distillate fuel oil
1. Subtract residential distillate oil from DOE distillate
oil used for heating (Reference 6)
630,000,000 - 500,000,000 = 130,000,000 gallons
2. Allocate fuel to commercial/institutional and industrial
sector using Equation 2-7
ion n™ nnrv n / 300,000 employees SIC 50-99 \
130,000,000 gallons *(500ioOO employees SIC 20-39 and 50-99/
= 78,000,000 gallons for state commercial/institutional use and
52,000,000 gallons for state idustrial use
3. To commercial/institutional fuel above add distillate oil
for military use
78,000,000 + 42,000,000 = 120,000,000 gallons
4. Subtract state point source distillate oil use by the
commercial/institutional category (assumed 10,000,000
gallons) to obtain state commercial/institutional area
source distillate oil use: 110,000,000 gallons
5. To industrial fuel above add distillate oil used for
industrial and oil company use
52,000,000 + 168,000,000 = 220,000,000 gallons
6. Subtract state point source industrial fuel use (assumed
100,000,000 gallons) to obtain area source distillate oil
fuel use:
220,000,000 - 100,000,000 = 120,000,000 gallons
2-18
-------
B. Residual Fuel Oil
1. Because residual fuel oil use by the residential category
is 0 allocate state residual oil used for heating in
Reference 6 to commercial/institutional and industrial
categories using Equation 2-7.
i o^ ™« ™« n / State employment in SIC Groups 50-99 \
1,260,000,000 gallons x ^State employment in SIC Groups 20-39 and 50-99)
= 760,000,000 gallons for commercial/institutional
and 504,000,000 gallons for industrial use
2. To commercial/institutional fuel above add residual oil
for military use
756,000,000 + 21,000,000 = 777,000,000 gallons
3. Subtract state point source residual oil use by the
commercial/institutional category (assumed 500,000,000
gallons) to obtain state commercial/ institutional area
source residual oil use
777,000,000 - 500,000,000 = 277,000,000 gallons
4. To industrial fuel above, add residual oil used for
industrial and oil company use
504,000,000 + 1,050,000,000 = 1,554,000,000 gallons
5. Subtract state point source residual oil use by the
industrial category (assumed 1,054,000,000 gallons) to
obtain state industrial area source residual oil use:
500,000,000 gallons
C. Natural Gas
1. State use of natural gas by the residential category is
given in Reference 7 as 72 x 10^ ft3. This is
slightly lower than calculated state total of 76 x 10^
ft-'. Use Reference 7 value and reduce calculated county
totals to (72)/76 or 0.947 of calculated values.
2. Allocate commercial and industrial total of
150,000,000,000 ft3 from Reference 7 using Equation 2-7
to give
2-19
-------
90 x 109 ft-* commercial/institutional, and
60 x 109 ft3 industrial.
3. Subtract state point source natural gas use by the
commercial/institutional and industrial categories from
the respective values above to obtain state area source
natural gas totals (assumed 50 percent in point source
inventory)
State area source totals are
45 x 10° ft3 commercial/institutional, and
30 x 109 ft3 industrial
D. Anthracite Coal
1. Calculated state residential coal consumption is 300,000
tons. This is greater than the 150,000 tons of anthracite
shipped to state.
2. Assign all anthracite to residential after subtracting
point source anthracite (20,000 tons by industry). State
residential anthracite fuel use is 130,000 tons.
Commercial and industrial area source totals are 0.
E. Bituminous Coal
1. Assign difference between calculated state area source
residential coal and area source anthracite residential
coal to bituminous coal.
300,000 - 130,000 = 170,000 tons
2. The difference between state bituminous retail sales in
tons from Reference 9 and the 170,000 tons of residential
coal or 160,000 tons is assigned to the commercial
category.
3. Subtract state point source commercial/ institutional
bituminous to obtain state area source
commercial/institutional bituminous use.
4. Subtract state point source industrial bituminous use from
total industrial sales in tons given in Reference 9 to
obtain state area source industrial bituminous use.
2-20
-------
Step IV Apportion state area source fuel use to counties
A. Residential fuel use by county is based on calculations as
described above.
B. State area source commercial/institutional fuel is apportioned
to counties on the basis of population
County C/I area source fuel use =
State C/I area source
,. i /County population\
fuel x (-— * r r, . 1
\State population /
For Natural Gas; county commercial/institutional
area source natural gas use is:
/•; m9 / 300,000
45 X 10 X \3 .000.000
9 3
= 4.5 x 10 ft
C. State area source industrial fuel is apportioned to counties on
the basis of area source employment in SIC Groups 20-39.
Assumed 10,000 and 100,000 point source employees in county and
state SIC Groups 20-39, respectively.
For natural gas; county industrial area source natural gas use
is:
,0 ,_9 , 3 (20,000 - 10,000 county employees
x rt x ^300j000 _ 100,000 state employees
= 1.5 x 109 ft3
EXAMPLE 2. Updating and estimating residential fuel consumption by grid.
Given:
County and census-tract data for 1978 have been distributed onto
grids. The following population and dwelling units (DU) data are
available for one grid in the country:
County A Grid 4
1978 population 300,000 10,000
1978 DU 100,000 4,000
1978 DU using coal 10,000 500
2-21
-------
1978 DU using oil 40,000 1,300
1978 DU using gas 35,000 1,800
1978 DU using electricity 15,000 400
Local planning commission population and housing estimates for
County A in 1981 are as follows:
1981 population: 315,000
1981 DU: 105,000
Since 1978, according to the local gas company:
10 percent of the dwelling units using coal have switched to
gas.
5 percent of the dwelling units using oil have switched to gas,
80 percent of the homes built since 1978 are heated with gas
and 20 percent with electricity.
Total residential gas sales for 1981 are 9.1 x 10^ ft^.
Other:
In 1981, 20 percent of coal burned was anthracite and 80
percent was bituminous.
1981 degree-days (°day) = 5,000 "day.
Average number of rooms per dwelling unit, 1981 =5.5 rooms.
Dwelling units in County A using oil for water heating, 1978 =
20,000 DU or 50 percent; 25,000 dwelling units use natural gas
for water heating and cooling (1981).
Calculations:
Step I Update grid population from 1978 to 1981.
' (10,000 pop.) = 10,500 population in grid 4
2-22
-------
Step II Update grid housing data from 1978 to 1981
' (4>000 DU) = 4>200 DU in §rid 4
Step III Estimate 1981 coal usage for space heating in grid 4.
A. Dwelling units:
500 - (0.1) (500) = 450 DU using coal
B. Usage in Tons:
(-, f., 1000 \
7'64 ~ 5000 )
\ f —.
(0.00387) (450) exp \ / = 2970 (Equation 2-5)
1. Anthracite coal burned = (2,970 tons) (0.2) = 594 tons
2. Bituminous, coal burned = (2,970 tons - 594 tons) = 2376
tons
Step IV Estimate 1981 oil use for space heating and water heating in grid
4. All oil is assumed to be distillate oil.
A. Dwelling units:
40,000 - (0.05) (40,000) = 38,000 DU using oil, County A
1,300 - (0.05) (1,300) = 1,235 DU using oil, grid 4
B. Usage in Gallons
(Q.01288) (5000 "day) + 30.41 (5.5 rooms) - 79.54
0.14
250 (1,235 DU) (0.5) = 1,496,291 gallons fuel oil (Equation 2-1)
Step V Estimate 1981 natural gas use for space heating and other purposes
(water heating, cooking, etc.)
A. Dwelling units:
The following formula is used in this example for updating:
1978 DU gas users + converted from coal + converted from oil +
new DU using gas = 1981 DU gas users.
2-23
-------
County: 35,000 + 1,000 + 2,000 + 5,000 (0.80) = 42,000 DU
Grid: 1,800 + 50 + 65 + 200 (0.80) - 2,075 DU
B. Gas used in 1981.
County: 47.5 x 42,000 DU x 50000'367 x (42,000/25,000)°'588 x
5.50.125 = 42.3 x 106 therms (Equation 2-3)
42.3 x 106 therms x 95 ft3 gas/therm = 4.1x 109 ft3 gas
used in County A.
Grid: (2,075 DU/42,000 DU) 4.1 x 109 ft3 = 203 x 106
ft3 gas used in Grid 4.
Emissions estimates can now be obtained by multiplying fuel use totals by
appropriate emission factors.
2.2 STATIONARY INTERNAL COMBUSTION ENGINES
Internal combustion sources for electricity generation, industrial, and
commercial/institutional applications are grouped into two types: gas
turbines and reciprocating engines. A basic gas turbine consists of a
compressor, a combustor and a turbine. High pressure air is supplied by the
compressor to the combustor. Fuel is mixed with the air in the combustor and
burned. Combustion products are then expanded through the turbine to drive a
rotor and generate power. A variety of advanced models have evolved from the
simple gas turbine, and are classified into three general operating cycles:
simple open cycle, regenerative open cycle and combined cycle. In the simple
open cycle, the hot gas discharged from the turbine is exhausted to the
atmosphere. In the regenerative open cycle the gases are passed through a
heat exchanger to preheat the combustion air. Preheating the air increases
the efficiency of the turbine. In the combined cycle, the gas discharged from
the turbine is used as auxiliary heat for a steam cycle. The combined cycle
system offers a great increase in the combined efficiency of the overall
system. Gas turbines use gas or liquids, such as distillate oil and kerosene,
as fuel. In open cycle gas turbines, where the products of combustion come in
direct contact with the turbine blades, combustion gases must be free of
corrosive ash and large particulates (>2 \im) which cause erosion.
Reciprocating internal combustion engines may be classified according to
the method of ignition into spark ignition and compression ignition engines.
The spark ignition engines use gas or volatile liquids such as gasoline as
fuel, whereas the compression ignition engines use liquid fuels of low
volatility such as low-grade kerosene and distillate oil (diesel fuel). All
distillate oil reciprocating engines are compression ignited, and all gasoline
reciprocating engines are spark ignited. Spark ignited gasoline engines have
very limited use for electricity generation and industrial applications,
because of their poor part-load economy and demand for premium fuel. Gas-
fired reciprocating engines are mostly spark ignited, but gas can also be used
in a compression ignition engine if a small amount of diesel fuel is injected
2-24
-------
into the compressed air/gas mixture to initiate combustion. Such compression
ignition engines are known as dual-fuel engines, and are normally designed to
burn any mixture ratio of gas and diesel fuel. Most of the large bore, high
power engines for utility and industrial applications are four-stroke cycle
compression ignition engines designed to operate on diesel fuel or dual-fuel,
and either two-stroke cycle or four-stroke cycle spark ignited gas engines.
2.2.1 POPULATION OF INTERNAL COMBUSTION SOURCES
Gas turbine and reciprocating engine capacity in 1978, and areas of
application, are shown in Tables 2-2 and 2-3. respectively.^ Utility
systems are included in these tables for reference. However, they are not
area sources and should appear in the point source inventory, as should many
of the larger units in excess of 1000 hp (746 kw) output in size used for
electricity generation and heavy-duty compressor and pump drive applications.
Commercial/ institutional internal combustion sources are generally
reciprocating engines burning either natural gas or fuel oil. There are
approximately 4000 engines currently in use by municipalities for water and
sewage pumping. Average size is 400 hp or approximately 0.3 megawatts
(MW).* At an average thermal input rate of about 7,500 Btu/hp-hr for
reciprocating engines, these units consume about 3 x 10" Btu/hr and emit
less than 100 ton/year of any criteria pollutant. They generally should be
considered as area sources, as should a larger number of smaller units used
for light-duty applications and emergency power generation.
The lack of data concerning the number, size, areas of application, and
hours of operation of small to medium size internal combustion systems
presents serious problems to the agency interested in compiling an inventory
of emissions from this source category. Although stationary internal
combustion sources consume a relatively small percentage (~>10 percent) of all
fuel consumed by stationary combustion sources, it has been estimated that
they account for approximately 20 percent of NOX and 9 percent of
hydrocarbon stationary source combustion emissions. The preponderance of
emissions are from the industrial sector, with 80 percent of industrial
emissions attributed to reciprocating engines.^
2.2.2 ESTIMATING FUEL CONSUMPTION
There are no literature sources that can be used to estimate fuel use by
small and medium size stationary internal combustion sources. A survey by the
agency of manufacturers, oil and gas companies (the principal industrial users
of such systems), and municipalities will be required. A survey is
particularly important in states that have oil and gas transmission pipelines
and oil and gas production activities.
^1000 horsepower (hp) = 746 kw; 1 MW = 1341 hp.
2-25
-------
TABLE 2-2. CURRENT AND PROJECTED GAS TURBINE INSTALLED CAPACITY
FOR UTILITY AND INDUSTRIAL APPLICATIONS
Application area
(average capacity)3**1
Utilities (30 MW)
Oil-fueled combustion turbine
Gas-fueled combustion turbine
Oil-fueled combined cycle
Gas-fueled combined cycle
Oil and gas industry (2.2 MW)
Private industry electricity generation
Oil and gas industry
Other industry
Other industrial applications
Total
Installed capacity (MW)'
1978
41,500
3,410
3,760
2,130
5,390
490
2,400
1,080
60,160
1985
49,100
2,910
8,770
1,580
5,950
540
3,600
1,620
74,070
al MW - 1,000 kW - 1,341 hp.
turbines larger than 0.745 MW may be point sources. This
depends on the fuel composition, usage rate and point source size
cut-off chosen by the agency.
2-26
-------
TABLE 2-3. RECIPROCATING ENGINE INSTALLED CAPACITY FOR UTILITY,
INDUSTRIAL, AND COMMERCIAL/INSTITUTIONAL APPLICATIONS
1978
installed
Application area capacity
(average capacity) (™*'
Utilities (1.9 MW)
Diesel, dual fuel, and gas engine 5,300
Oil and gas transmission (1.5 MW)
Diesel engine 780
Gas engine 9,380
Natural gas processing
Gas engine 2,350
Oil and gas exploration
Diesel engine 840
Gas engine 840
Crude oil and natural gas production
Gas engine 4,000
Industrial processes
Gas engine 940
Onsite power generation
Gas engine 350
Municipal water and sewage (0.3 MW) 1,200
Total 25,980
2-27
-------
2.2.3 CALCULATING EMISSIONS
Emissions from internal combustion sources are estimated by multiplying
fuel consumption by an emission factor. Emission factors are given in AP-42
for pipeline compressor engines firing natural gas, and for gas- and oil-fired
electric utility turbines. The EPA Regional Office should be contacted for
information concerning emission factors for smaller area source internal
combustion sources. Recent information may now be available as a result of
EPA-sponsored NSPS and emissions assessment programs.
References for Chapter 2.0
1. Preliminary Emissions Assessment of Conventional Stationary
Combustion Systems, Volume II, EPA-600/2-76-046b, U.S. Environmental
Protection Agency, Research Triangle Park, NC, March 1976.
2. Emissions Assessment of Conventional Stationary Combustion Systems:
Volume II. Internal Combustion Sources, EPA-600/7-79-029c, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
February 1979.
3. Procedures for the Preparation of Emission Inventories for Volatile
Organic Compounds, Volume I, Second Edition, EPA-450/2-77-028, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
September 1980.
4. Standard Industrial Classification Manual, Executive Office of the
President, Office of Management and Budget, Washington, DC, 1972.
5. Compilation of Air Pollutant Emission Factors, AP-42, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
October 1980.
6. Energy Data Reports, Sales of Fuel Oil and Kerosene, U.S. Department
of Energy, Energy Information Administration, Washington, DC, Annual
Publication.
7. Energy Data Reports, Natural Gas Production and Consumption, U.S.
Department of Energy, Energy Information Administration, Washington,
DC, Annual Publication.
8. Energy Data Reports, Sales of Liquified Petroleum Gas and Ethane,
U.S. Department of Energy, Energy Information Administration,
Washington, DC, Annual Publication.
9. Energy Data Reports, Coal-Bituminous and Lignite, U.S. Department of
Energy, Energy Information Administration, Washington, DC, Annual
Publication.
2-28
-------
10. Energy Data Reports, Coal-Pennsylvania Anthracite, U.S. Department
of Energy, Energy Information Administration, Washington, DC, Annual
Publication.
11. Statistical Abstract of the United States, U.S. Department of
Commerce, Bureau of the Census, Washington, DC, Annual Publication.
12. 1978 National Emissions Data System (NEDS) Fuel Use Report,
Monitoring and Data Analysis Division, U.S. Environmental Protection
Agency, Research Triangle Park, NC, October 1980. Unpublished.
13. 1970 Census of Housing, "Advance Report," Series HC-(Vl), Bureau of
the Census, U.S. Department of Commerce, Washington, DC, 1971.
14. 1970 Census of Housing, Detailed Housing Characteristics, HC-B
Series, Bureau of the Census, U.S. Department of Commerce,
Washington, DC, 1971.
15. Local Climatological Data: Annual Summary with Comparative Data,
U.S. Department of Commerce, Washington, DC, Annual Publication.
16. Gas Facts, American Gas Association, Arlington, Virginia, 22209,
Annual Publication.
17. Gas Home Heating Survey, American Gas Association, Arlington,
Virginia, 22209, Annual Publication.
18. Fuel Oil and Oil Heat, Industry Publications, Cedar Grove, New
Jersey, 07009, Annual Publication, (October).
19. County Business Patterns, Bureau of the Census, U.S. Department of
Commerce, Washington, DC, Annual Publication.
20. Control Techniques for Lead Air Emissions, Volume I,
EPA-450/2-77-012, U.S. Environmental Protection Agency, Research
Triangle Park, NC, December 1977.
21. National Air Data Branch, U.S. Environmental Protection Agency,
Research Triangle Park, NC, 27711.
2-29
-------
3.0 SOLID WASTE INCINERATION AND OPEN BURNING
The areas of solid waste incineration and open burning have changed
substantially since the 1970's because of the enactment of air pollution
regulations. There has been a marked decrease in the number of operating
incinerators and open burning has been banned in many states and
municipalities. Due to this reduction in activity level, procedures based on
correlative relationships used previously to compile an inventory of emissions
from these sources are for the most part outdated. This section outlines
procedures for inventorying these sources using the best available and most
current information. Agency personnel must exercise judgment in assessing the
quantitative value of these procedures as applied to the agency's inventory
jurisdiction.
3.1 SOURCE CATEGORIES
Source categories falling under the major heading of solid waste
incineration and open burning include those listed in Table 3-1. Prescribed
burning and wildfires are distinct categories, and are distinguished from the
incineration and open burning categories that burn wastes generated by
residential, commercial and industrial sources.
Many facilities in the source categories listed in Table 3-1, such as
municipal incinerators and many industrial incinerators, will be point sources
or located at a major facility included in the point source inventory.
Emissions from those facilities accounted for in the inventory of point
sources must not be included in the inventory of area sources.
f
3.2 INCINERATION
Incineration (and open burning) sources are classified according to
origin into residential, commercial/institutional and industrial categories.
Criteria pollutant emissions from incineration are affected by the type of
waste burned, incinerator design, and the presence of stack gas control
equipment. The type of waste incinerated will affect emissions due to
variations in such factors as: moisture content, heating value, chemical
composition and ash content. However, the effect of these factors on
emissions from urban wastes have not been quantified. The emission factors
given in AP-^42 are average values; i.e., all urban refuse wastes are assumed
to be homogeneous.
Incinerator design has a direct bearing on emissions. Consequently, area
source emission calculations are based on the design mix of area source
incinerators. The area source incineration population is classified according
to incinerator design as follows:
3-1
-------
TABLE 3-1. SOLID WASTE INCINERATION AND OPEN
BURNING SOURCE CATEGORIES
Incineration
Residential
Commercial/Institutional
Industrial
Open Burning
Residential
Commercial/Institutional
Industrial
Prescribed Burning
Agricultural
Slash
Frost Control
Leaf
Forest Fires
Structural Fires
3-2
-------
Single Chamber—the earliest and simplest design, consisting of one
combustion chamber. These constitute approximately 25 percent of all
incineration units currently operating.
Multichamber—equipped with an ignition as well as a combustion chamber.
These units have a much lower emission rate than single chamber units of
comparable size. Their primary use is in commercial and industrial
applications. Multichamber units comprise approximately 68 percent of
all area source incinerators.
Controlled Air—they combine tight combustion air controls with a
built-in afterburner. The relatively sophisticated design and controls
built into controlled air units result in substantially lower emission
rates. The majority of these units are currently used to incinerate
pathological wastes. Recent documents indicate that controlled air
incinerators make up 2 percent of the total incinerator population.
However, this percentage is likely to increase as more stringent emission
controls become mandatory.
The breakdown of incinerator design for residential, commercial/
institutional, and industrial incinerators has been determined by EPA for the
year 1975. This distribution is shown in Table 3-2. As shown in Table 3-2,
all residential incinerators are assumed to be single chamber units. However,
the residential single chamber units are further classified as:
Flue-fed (modified) for urban-residential
Single chamber without primary burner for rural-residential
TABLE 3-2. INCINERATOR DESIGN DISTRIBUTION2
Residential Commercial/institutional Industrial
Single
Chamber
100%
25%
38%
Multiple
Chamber
73%
58%
Controlled Air
4%
Total
100%
100%
100%
3-3
-------
In an inventory of area source incinerators, it is assumed that the
sources are not equipped with stack gas control equipment. Generally,
incinerators that are equipped with emission control systems to achieve
emission standards are point source incinerators.
3.2.1 PROCEDURES FOR INCINERATOR EMISSION INVENTORY PREPARATION
Emissions from area source incinerators are estimated by identifying the
activity level of each incinerator subcategory (i.e., residential, commercial/
institutional and industrial) and then applying an appropriate emission factor
to obtain subcategory emissions. The agency will need to maintain separate
records in the inventory for each subcategory. A separate subcategory record
permits changes in this record as specific subcategory source changes occur,
such as the outlawing of open burning or the outlawing of single chamber
incinerators.
3.2.1.1 Determination of Activity Level
The quantities of waste disposed of by onsite incineration are shown in
Table 3-3. The estimates are provided by EPA region, as a function of
population or employment. The factors, in conjunction with population and
employment data obtained from Department of Commerce publications,^'^ can be
used, if necessary, to estimate emissions from incineration. However, the
data shown in Table 3-3 are 1975 data and subject to large local variations.
Thus, the agency must make use of local surveys, permit and registration files
and regulatory statutes to estimate activity levels, if a defensible inventory
of onsite incineration emissions is to be maintained in the area source file.
The agency should conduct a survey of a representative sector of the
inventory region for the purpose of developing or modifying the waste
generation factors presented in Table 3-3. Additional data sources that may
provide assistance are:
Air Quality Agency Data
Source registrations
- Construction and operating permits
Source inspection reports
Existing emission inventory
Special solid waste studies
Solid Waste Agency Data
- Waste generation rates
Solid waste categorization studies
3-4
-------
TABLE 3-3. FACTORS TO ESTIMATE TONS OF SOLID WASTE BURNED IN
ONSITE INCINERATION3>b
EPA Region
Residential
(ton/1000
population/yr)
Commercial/
institutional
(ton/1000
population/yr)
Industrial
(ton/1000 mfg
employees/yr)
I
II
III
IV
V
VI
VII
VIII
IX
X
National Average
Incineration
52
11
4
4
61
23
75
87
90
90
41
64
65
54
23
87
33
37
49
5
29
50
125
180
560
395
420
345
325
430
80
170
335
References 2 through 6.
"These factors are based on 1975 data and should be updated to the inventory
base year.
3-5
-------
Waste disposal studies
Waste Disposal Firms
Waste generation rates by industry sector
- Population served by service
Trends in waste generation rates and onsite disposal techniques
Incinerator Manufacturers
Facilities with new installations
Trends in onsite incineration
County/Local Fire Marshals
Structural fires
Trends in onsite incineration
Fuel Suppliers/Gas Company
Customers utilizing auxiliary fuel for incinerators
3.2.1.2 Emission Factors for Incineration
Emission factors for onsite incineration are presented in EPA publication
AP-42. These emission factors are for refuse incinerators without emission
controls. As previously stated, it is assumed that area source incinerators
are not equipped with control equipment. Consequently, the emission factors
in AP-42 can be used directly. (AP-42 emission factors are being updated
continuously; the agency should verify that the factors are current).
The emission factors for incinerators are expressed in terms of pounds of
pollutant per ton of waste charged. When multiplied by the appropriate
activity levels (tons of waste incinerated), they will yield uncontrolled
emission rates.
3.2.2 EXAMPLE CALCULATION: EMISSIONS FROM INCINERATORS
The following example is presented to illustrate the general procedures
for evaluating emissions generated by area source incinerators.
Given: The inventory region is located in EPA Region V.
Step I Determine the Activity Level
3-6
-------
From Table 3-3 the waste generation factors to estimate onsite
incineration are:
Residential: 61 tons/1000 population
Commercial/Institutional: 87 tons/1000 population
Industrial: 420 tons/1000 manufacturing employees
A survey of a representative sector of the inventory region (group of
counties of the state) shows that the above waste generation factors are high
by roughly 35 percent for each category. The modified activity level factors
are then calculated to be:
Residential: 40 tons/1000 population
Commercial/Institutional: 56 tons/1000 population
Industrial: 273 tons/1000 manufacturing employees
A review of the point source incinerator file shows that Agency personnel
involved in the point source inventory have determined 50 percent of all
commercial/institutional wastes and 85 percent of all industrial wastes are
accounted for in the point source inventory. The activity levels are modified
to represent only area source incinerators:
Residential: 40 tons/1000 population
Commercial/Institutional: (56)(0.5) = 28 tons/1000 population
Industrial: 273 (0.15) = 41 tons/1000 manufacturing employees
Step II Determine Activity Levels as a Function of Incinerator Design
The activity levels for each category can now be proportioned among
incinerator design types (i.e., single chamber, multiple chamber, and
controlled air) from Table 3-2.
Residential (given the inventory region is 25 percent urban and 75
percent rural):
Flue fed modified: 40 (0.25) = 10 tons/1000 population/year;
Single chamber: 40 (0.75) = 30 tons/1000 population/year.
Commercial/Institutional:
Single chamber: 28 (0.25) = 7 tons/1000 population/year
Multiple chamber: 28 (0.73) = 20 tons/1000 population/year
Controlled air: 28 (0.02) = 0.6 tons/1000 population/year
Industrial:
Single chamber: 41 (0.38) = 16 tons/1000 manufacturing
employees/year
3-7
-------
Multiple chamber: 41 (0.58) = 24 tons/1000 manufacturing
employees/year
Controlled air: 41 (0.04) = 1.6 tons/1000 manufacturing
employees/year
Step III Obtain Population and Manufacturing Employee Statistics
From published
Population of inventory region: 5,500,000
No. of manufacturing employees: 550,000
Step IV Obtain Particulate Emission Factors (AP-42)
Residential:
Flue fed: 6 Ib/ton
Single chamber: 35 Ib/ton
Commercial/Institutional:
Single chamber: 15 Ib/ton
Multiple chamber: 7 Ib/ton
Controlled air: 1.4 Ib/ton
Industrial:
Single chamber: 15 Ib/ton
Multiple chamber: 7 Ib/ton
Controlled air: 1.4 Ib/ton
Step V Calculate Emissions
Emission Estimate = Activity Data x Population Employment x Emission
Factor
Residential:
Flue fed modified: 10 tons/1000 population/yr x 5,500 x 6 Ib/ton
= 330,000 Ib/yr
Single chamber no primary burner: 30 tons/ 1000 population/yr x
5,500 x 35 Ib/ton = 5,775,000 Ib/yr.
Commercial /Institutional:
Single chamber: 7 tons/1000 population/yr x 5,500 x 15 Ib/ton
= 577,500 Ib/yr
Multiple chamber: 20 tons/1000 population/yr x 5,500 x 7 Ib/ton
= 770,000 Ib/yr
Controlled air: 0.6 tons/1000 population/yr x 5,500 x 1.4 Ib/ton
= 4,620 Ib/yr
Industrial:
Single chamber: 16 tons/1000 manufacturing employees/yr x 550
x 15 Ib/ton = 132,000 Ib/yr
3-8
-------
Multiple chamber: 24 tons/1000 manufacturing employees/yr x 550
x 7 ib/ton = 92,400 Ib/yr
Controlled air: 1.6 tons/1000 manufacturing employees/yr x 550
x 1.4 Ib/ton = 1,232 Ib/yr.
If desired, total emissions may be calculated by summing total residential,
commercial/institutional and industrial emissions as follows:
Emissions = 339,000 + 5,775,000 + 577,500 + 770,000 + 4,620
+ 132,000 + 92,400 + 1,232
= 7,682,752 Ib/yr (3,841 tons/yr)
3.3 OPEN BURNING
As stated in Section 3.1 the agency should be aware that prescribed
burning and wildfire emission sources are distinct categories. Consequently,
these categories should not be included in the open burning category.
As with small incinerators, the activity level for open burning can not
be accurately correlated to some other easily identifiable factor such as
population. The economic and regulatory climate for open burning varies
throughout the country, and consequently, any general assumptions concerning
open burning activity levels are not practical.
To determine emissions from open burning sources, the agency must develop
accurate estimates of the activity levels. Existing regulations and their
effectiveness should be considered by the agency in developing these
estimates. Because many areas of the country require burning permits, an
estimate of the activity level in those areas can be obtained by contacting
the local officials responsible for issuing permits. Additional information
can often be obtained from state agencies in charge of regulating solid waste
disposal. If information cannot be obtained at either the local or state
level, then nationally averaged activity level factors must be used. Table 3-4
provides factors for estimating the quantity of waste disposed of by open
burning by the residential, commercial/institutional and industrial categories
(1975 data). It is important to stress the limitations of these data when
applied to specific local areas.
The procedures followed for calculating emissions are generally the same
as previously detailed for incinerator sources. The quantities of waste
accounted for in the point source open burning file should be subtracted from
the factors in Table 3-4 before calculating the area source emissions.
3-9
-------
TABLE 3-4. FACTORS TO ESTIMATE TONS OF SOLID WASTE DISPOSAL
THROUGH OPEN BURNING3
Industrial,
Residential, Commercial/institutional, tons/1000
tons/1000 population/yr tons/1000 population/yr mfg. employees/yr
National 450b 24 160
Average
aThese factors should be updated to the inventory base year.
"For rural population only. Open burning assumed banned in urban areas.
Source: References 3 through 7.
3.4 PRESCRIBED FIRES
The prescribed burning category includes agricultural burning, slash
burning, leaf burning and orchard heaters for frost control. These source
categories have a seasonal occurrance and therefore a characteristic time when
they release emissions. The agency should account for these temporal
variations in the emission rate by estimating and recording emissions for the
most active month(s) or season in addition to the annual emission totals.
3.4.1 AGRICULTURAL BURNING
Estimates of burning activity can usually be derived from data provided
by State Agricultural Departments or extension services. Additional data may
be obtained from the U.S. Soil Conservation Service. Emission factors for a
variety of agricultural crops are obtained from Section 2.4 of EPA Publication
AP-42.1
3.4.2 SLASH BURNING
The agency should consult with the U.S. Forest Service and State Forest
Departments to obtain data on area and fuel loading of slash burned areas. If
fuel loading data are unavailable, a figure of 75 tons per acre burned can be
used. Emission factors in Section 2.4 of AP-421 can be applied to this loading
factor.
3.4.3 FROST CONTROL
Typically, the county or State Department of Agriculture will be able to
identify the number, location and type of orchard heaters in use. Grove and
orchard operators may also provide such data. These sources will also furnish
3-10
-------
the number of nights and the length of time the units were used during the
year. From these data, hours of operation can be determined and emissions
computed using emission factors given in AP-42.
3.4.4 LEAF BURNING
In order to estimate the activity level, the agency should contact the
local or state agency in charge of issuing leaf burning permits. Emission
factors, provided by AP-42, are used to calculate emissions.
3.5 FOREST FIRES
Data on forest fires may be available from State Forest Departments. If
not, then Wildfire Statistics will provide data on acreage burned on a
state-wide basis.** Fuel loading, emission factors, and estimates of organic
emissions from forest fires in various U.S. Forest Service regions are found
in Section 11.1 of EPA Publication AP-42.1
3.6 STRUCTURAL FIRES
For information, contact local fire departments or fire protection
associations. In the absence of such information, assume an average of four
fires/1000 people/year.^ The EPA Regional Office should be contacted to
assist in the selection of appropriate emission factors.
References for Chapter 3.0
1. Compilation of Air Pollution Emission Factors, Third Edition and
Subsequent Supplements, AP-42, U.S. Environmental Protection Agency,
Research Triangle Park, NC, October 1980.
2. Screening Study to Determine the Need for Standards of Performance
for Industrial and Commercial Incinerators, Draft Final Report, EPA
Contract No. 68-02-2607, Work Assignment No. 18, October 1978.
3. Census of Population, Bureau of the Census, U.S. Department of
Commerce, Washington, DC, Decennial publication.
4. County Business Patterns, U.S. Department of Commerce, Bureau of the
Census, Washington, DC, Annual publication.
5. National Survey of Community Solid Waste Practices: Interim Report,
U.S. Department of Health, Education and Welfare, Cincinnati, OH,
1978.
6. National Survey of Community Solid Waste Practices: Preliminary
Data Analysis^ U.S. Department of Health, Education and Welfare,
Cincinnati, OH, 1978.
3-11
-------
7. OAQPS Data File of Nationwide Emissions, 1971, Monitoring and Data
Analysis Division, U.S. Environmental Protection Agency, Research
Triangle Park, NC, May 1973. Unpublished report.
8. Wildfire Statistics, Forest Service, U.S. Department of Agriculture,
Washington, DC, Annual publication.
9. Statistical Abstract of the United States, Bureau of the Census,
U.S. Department of Commerce, Washington, DC, Annual publication.
3-12
-------
4.0 FUGITIVE DUST SOURCES
Fugitive dust emissions are particulate matter entrained and suspended by
wind, vehicular traffic or other means. The following categories are
recognized sources of fugitive dust emissions.
Anthropogenic sources
- Unpaved roads
Unnpaved airstrip LTOs
- Paved roads
Agricultural activities
Construction activities
Feed lots
- Miscellaneous industrial area sources
Natural sources
- Wind erosion of miscellaneous open areas.
It should be noted that fugitive dust emissions from all of the above
anthropogenic sources, with the exception of the feed lot category, are
associated, at least in part, with the operation of mobile sources, i.e.,
fugitive dust emissions are primarily the result of vehicle related traffic
and LTOs. These fugitive dust categories are maintained separately in the
area source file distinct from the inventory of mobile source tailpipe
(combustion related) and crankcase and evaporative loss emissions which are
the subject of Volume IV, Mobile Sources. The distinction between the
fugitive dust and mobile source categories is maintained because of
significant differences in inventorying procedures, the pollutants emitted and
methods of control. Mobile sources, although significant emitters of
suspended particulates, including inhalable particulates and lead, are the
major emitters of NOX, VOC, and CO in urban areas. Fugitive dust sources
emit only particulates. As shown in Table 1-1, nationwide fugitive emissions
from unpaved roads are six times greater than particulate emissions from
mobile sources (combustion related) and over 20 times greater than all other
area sources of particulate matter, including the previously discussed
combustion and incineration area sources.
Historically, due to the difficulty in measuring fugitive dust emissions,
little attention has been given to these sources. However, in view of the
widespread failure to attain the NAAQS for particulate matter in many AQCRs,
4-1
-------
these sources are currently undergoing rigorous examination. It now appears
that fugitive dust emissions (principally from unpaved roads) are the major
cause of nonattainment of NAAQS in many areas, and that a thorough inventory
of such sources is mandatory for the development of an accurate inventory of
particulate emissions.
A 1978 EPA report 1 stated that ambient air quality standards for total,
suspended particulates (TSP) were not being met in 60 percent of the nations
247 air quality control regions (AQCRs). Estimated fugitive particulate
emissions exceeded particulate emissions from point sources in over 90 percent
of the 150 AQCRs that were out of compliance. In nearly 40 percent of the
AQCRs, fugitive dust emissions exceeded point source particulate emissions by
a factor of 10.^ In AQCRs where industrial activity is absent, fugitive
dusts are probably responsible for observed TSP standard violations. However,
fugitive dusts also contribute significantly to ambient TSP levels in highly
industrialized urban areas. The annual open source contribution to TSP levels
in industrialized urban areas may be greater than 25 ug/m^, or in excess of
one-third of the primary NAAQS of 75 yg/nH (annual geometric mean).^
As a result of the past lack of attention given to fugitive dust
emissions, the data base describing emission rates has not been been
adequately defined. Although fugitive emission factors for many open source
categories have been published in AP-42^ and other EPA publications, the
reliability rating for the majority of these factors is not high. Engineering
judgment and extrapolation from related sources have played a large part in
fugitive dust emission factor development, and few of the emission factors are
supported by extensive test data. However, several programs are now ongoing
to further refine existing emission factors and develop emission factors for
other fugitive dust sources. New developments must be closely followed by the
agency to update fugitive dust emission factors, and, thus, improve the
accuracy of this important segment of the total particulate matter inventory.
Emission factors for fugitive dust sources are, in most cases, specific
to a given geographical area. They are often dependent upon a number of
parameters, including soil characteristics and climate. Sound professional
judgment must be exercised by agency personnel in adjusting existing emission
factors to reflect local conditions.
4.1 DATA REQUIREMENTS
Prior to the collection and validation of the data required for the
estimation of emissions from fugitive dust sources, the agency must prepare
the following:
1. A list of all fugitive dust source categories which exist within the
agency's jurisdiction. This includes potential industrial-related
area sources.
4-2
-------
2. A list of the parameters necessary for the calculation of emissions,
including activity levels and emission factors and their associated
parameters.
3. A list, if necessary, of the data needed for the spatial and
temporal resolution of emissions and for projection of emissions.
The list of fugitive dust sources should be as complete as possible to
establish the impact of all source categories on the total inventory.
Although considerable effort may be required initially to establish the impact
of all potential source categories, this effort will contribute to the
reliability of the inventory and will simplify future inventory efforts and
updates.
Data requirements for the calculation of emissions are best identified by
examination of the equations used to calculate emissions from open fugitive
dust sources. As noted previously, formulae have been developed which provide
for the application of correction factors which reflect the effect of local
transportation, soil and climatic conditions. Emissions from industry-related
sources will require careful consideration, but in most cases can be estimated
using techniques developed for identical or related point sources.
Equations for uncontrolled emission rates from major open fugitive dust
emission sources are given in Table 4-1. As shown, a number of factors
influence emissions from certain source categories. These factors are often
difficult to quantify. As a result, estimated values or simplified equations
are often used. Miscellaneous industrial processes such as small grain
elevators and woodworking operations are not listed in Table 4-1. Emission
estimates from these industrial sources must be based on estimated activity
levels determined through association with the number of employees, production
rates or other statistical indicators, and emission factors based on, or
extrapolated from, similar or related point sources and/or engineering
judgment.
A definition of data requirements for all area source categories
logically precedes the collection of data for purposes of estimating activity
levels, deriving emission factors, and apportioning, as necessary, emissions
from each source category to the geographical area of interest. This is
particularly true of fugitive dust area sources because of the large number of
corrective factors that are used to adjust emission factors.
4.2 DATA SOURCES
Having defined the data requirements for preparing an inventory of area
source fugitive dust emissions, agency personnel will be required to collect
the data necessary for estimating emissions of fugitive dust. As shown in
Table 4-1, data related to transportation, climate, and agriculture are common
requirements for estimating emissions from most fugitive dust sources. State
and local agencies associated with such activities should be able to supply
the information required.
4-3
-------
cd
x™x
/"\
ro
.j
t»
y
g
8
s
£^
s
g
o
fj-l
H
o
H
CO
co
H
ft
u
Pi
P
o
CO
H
CO
P
O
W
^
H
H
M
go
•
t— 1
1
^
^^
w
t-J
3
H
co
O
.a
ca
B
0
4-1
CO
3
cr
W
ca
4->
• H
B
p
41
CO
^
B
O
• H
to
CO
•H
§
•O
01
i-H
0
o
o
B
0)
O
I-l
3
O
CO
B
O
^- B 41 CO
•a o •-! 4J
4) 4J .-^ -rl -H
<-> 6 to 60 0 CX
4) 4) /-N B B^-. -r«
> 4J J3 o to -i-itau
> O. CO M
4) i— 1 41 60 H 4J ^ 0)
i-l -i-l 0) -H T3 C4 4J B
•H CO 0. 4) 3 *T3 "•! O
a w 3 u-i T3 to 03 -H
i-l O V4 O 3 4J
4IC04I4) CO 4) I-l ,£ CO
O M O O 41 X CO T3 BO
•H 4) -r( -H A UH 4) VJ CX
jC4J.c.cgMt4>oco
41 CO 41 4) 341 3 CO JT >
> a > > ZO.COCXHW
1 1 1 1 1 1
| » co 3 -0 _l g
MM MM
^1 >"» ^ >•>
"*•«•. "^*«. *"*-.. ""^
GO CO W M
"S "§ "B ?
33 33
O O O O
1 — 1 1 ,-. -^
CN |m
/-N U-I CM
o •
"•«* ^ *^
elm
CQ|i— 1
V.X •
^•N ^ ^.
i i m lo
m m — — '
f) l 1 00 CO O
— - — ^— — . > s^ / O
in o *— i ~^
00 'O ^O >-• ^ ft^
• co ^ In co
O 1-1 X
»|n rH T3
^ ^. O O r-t
co co ox oi
• • rJ O -H
o m -o u-<
CO CO to • C
-, . o\ co 3
->
CM o ca 1-1 C ^
CO rH 1 1 • • CO CO
o m
C^ • o^ UH UH
• CM • O O
m o
i 1 x i 1 ta to
oi a>
fe O fc ^ ^
v i-i t-i M JE t-i u o
>>,,j><>>i^! <;
n ii n ii u
b3 W W W W
U-i
O
CO
•0 i-t B
co co co co O
o a. •« »j -H
l-i -rt co 3 60 ta
ti O 4J C O
TJ TJ 4J V4 i-l -H U
41 4) CO 3 i-l 41
> > to TJ O i-l
ex ex co > p 4J B
B B CO 60 -i-l
P D fc , J3 B
4J oi a. 3
•*^ a a
•|H ^4 4J CM 4)
t£ CO 1—4 ^
•rt 01 U-I -H
O 1 4) *~*
1-14) 4) 4)
0) ^i 60 O CO
U CO X B
CJ *"-* B *H
CO 10 4) T) CO
u-i B U 4) ca
I-l O IJ 01 -r-l
3 4J 41 CX B
CO ""^ CU CO (ij
1 1 1
4) U-l W
j.
4J
C
O l-i l-i
^a x x
co to co
B B B
O O O
H H H
t
CM
O
E
^^
1
00
X
0)
4J
CO 4-1 X
4) CO
MO to
U 4)
O M O
0) CO Vj CO
> -O 4) O
*J 41 O
O J3 r-<
<£
0 T3
CN O 4)
O 0)
II H II
W W W
CO
•0
i-H
4) B ca
• H O 4) •«
U-I ••-! -H 4)
4J 4-1 4)
3 0 -H U-I
O 3 >
i-H C -rl 4) CO
l— 1 U 4J i— 1 4J
CO CO O 4J O
UH S CO 4J l— 1
O CO
0 0
\o r**
V
»c
H
4)
4J
CO
•c
UH
0
4-1
O •
CM
4) -
-------
It is emphasized that data sources cannot always be precisely defined due
to differences in state and county government structure. Data not available
at the state or county level may be available from a specialized commission
charged, for example, with defining transportation and land use requirements.
Generally, information not available at the local level may be obtained from a
state agency.
When the desired data are not available at the state and local level, the
agency has the option of conducting a survey or a study of its own to develop
the data. The importance of the needed data may warrant doing so. If such a
study is not possible, the agency should derive an estimated value in as sound
a fashion as is possible. Although an estimate will not be as accurate as
data derived from actual measurement, the error can generally be estimated by
calculating the variance in emissions within a reasonable choice of boundary
conditions. The impact of the error on the total emissions inventory of
particulates can also be estimated by relating the emissions from the area
source category of interest to the emissions from the total inventory.
4.3 SOURCE CATEGORIES
4.3.1 UNPAVED ROADS
Unpaved roads, nationally, are the largest source of fugitive dust
emissions. According to one estimate, emissions from unpaved roads represent
almost 75 percent of the total national anthropogenic area and point source
particulate emissions combined. *• Road length; vehicle traffic, mix and
speed; type of surface; and road moisture content are the principal
determinants of the amount of dust generated by vehicle traffic on unpaved
roads.
In order to determine the length of unpaved roads and vehicle miles
traveled (VMT), the State Department of Highways or State Department of Public
Works should be contacted. These agencies will, in most cases, have very
accurate figures relative to the miles and type (e.g., gravel, silt) of
unpaved roads in the study area. They should also have a good estimate of the
average daily traffic, and thus VMT, for each segment of the study area. If
the number and length of unpaved roads within a study area are not known, an
alternative method of measuring road distances is to trace over the dirt roads
shown on Department of Highway maps with a curvimeter. This device reads
distance in either centimeters or inches which can be converted to road miles
using the map scale. Depending on the size of the area being inventoried,
this can be a quick and fairly accurate procedure.
Emissions data based on VMT data from previous years, given no change in
the miles of unpaved roads in the area, may be updated by using recent census
population figures for the area (usually county figures) and ratioing the VMT
accordingly. This is accomplished by the following equation:
population
VMT0 = VMT, x = : -
z 1 population.
4-5
-------
where: VMT2 = vehicle miles traveled in year y,
1 = vehicle miles traveled in year x,
populatio^ = population, year y, and
population^ = population, year x.
Some emission source parameters needed for estimating fugitive dust
emissions from unpaved roadways, along with the primary and most reliable
sources of information concerning these parameters, are listed in Table 4-2.
TABLE 4-2. EMISSION SOURCE PARAMETERS AND SOURCES OF INFORMATION
Source parameter
Data source
Length of unpaved road
Vehicle miles traveled—VMT
(average daily traffic x miles
of unpaved road)
Road base silt content
1. Department of Highways
2. Department of Public Works
3. Highway Map Measurement
1. Sources 1 and 2 above
2. Old data updated by census ratio
1. U.S.D.A. Soil Conservation Service
2. State or County Agricultural Agency
3. State or County Geological Agency
Once these parameters have been defined they can be applied to Equation 1 of
Table 4-1. Equation 1 is expressed as:
where
VMT
yr
5.!
E = emissions (in pounds/yr),
VMT = vehicle miles traveled,
s = road silt content (%),
S = vehicle speed (mph),
W = vehicle weight (tons), and
d = number of dry days per year.
ML
\365/
4-6
-------
Fugitive emissions can be considered insignificant on days when rainfall
exceeds 0.01 inches. Consequently, dry days are defined as those days in
which rainfall is less than 0.01 inches. Vehicle speed (S) and weight (W) can
be estimated with the assistance of personnel associated with one or more of
the state agencies listed as data sources in Table 4-2.
4.3.2 UNPAVED AIRSTRIPS
Reference information needed to calculate fugitive dust emissions from
unpaved airstrips can be obtained from the Federal Aviation Administration
(FAA). A computer tape with data on any U.S. airport can be obtained from the
Washington offices of the FAA.* Data include the following information: site
number, city, state, airport name, county code, latitude, longitude, airport
type, number of total based aircraft, runway pavement, runway length,
population served, ownership and usage type. Local FAA officials or airstrips
can also provide landing/takeoff (LTO) cycle estimates.
The following parameters are used in the calculation of fugitive
particulate emissions from unpaved airstrips:^
the surface texture, measured as percent silt content;
the average LTO speed, (can be estimated to be 40 mph);
the surface soil moisture as determined by annual number of dry days; and
a wind-erosion multiplier, estimated to be equal to 2.
Once these parameters have been defined, emissions can be calculated (for a
runway 1 mile in length) using Equation 2 of Table 4-1 which is:
0.49s fe
E =x 2.0
yr
30
where LTO = landing/takeoff cycles,
s = surface silt content (%),
S = average LTO speed, and
d = number of dry days per year.
4.3.3 PAVED ROADS
Emissions of dust from paved roads result from traffic or wind
re-entrainment of dust deposited on the road by mud carryout (e.g., trucks
*Aircraft Services Tape, Federal Aviation Administration, Public Information
Center, AIS 230, Washington, D.C., 20541.
4-7
-------
leaving construction sites), soil erosion, sanding and salting of roads, tire
wear, etc. To quantify emissions, the agency personnel will need to quantify
surface dust loading, in addition to many of the other parameters used to
estimate emissions from unpaved roads.
One source of surface dust loading information is Reference 8, which
presents minimum, maximum and average dust loading values for paved roads in
residential, industrial and commercial areas. Once the appropriate variables
have been determined they can be applied to Equation 3 of Table 4-1 which is:
where E = emissions (pounds/yr),
VMT = vehicle miles traveled,
s = silt content of surface dust (%),
L = surface dust loading (pounds/mile), and
W = vehicle weight (tons).
A simplified emission factor is provided in EPA publication AP-42 and
shows average emissions to be 0.012 pounds/VMT. This emission factor can be
used if the above parameters cannot be readily determined by the agency.
4.3.4 AGRICULTURAL ACTIVITIES
Fugitive dust emissions from agricultural activity occur during
agricultural tilling and from fields exposed to wind erosion. Emissions from
this category can range in magnitude from nonexistent to large depending on
whether the area inventoried is mostly urban or rural. Much of the reference
information required to perform an inventory of these sources can be obtained
from EPA publications (AP-42, and Reference 5) and the U.S. Soil Conservation
Service publication entitled "Guide for Wind Erosion Control in the United
States." This information includes:
Thornthwaite1s precipitation-evaporation (PE) index (see Figure 4-1)
Silt content of surface soil
Climatic factor (see Figure 4-2).
Surface erodibility—An estimate of the particulates per acre eroded from
the exposed field. Erodibility factors are given for general areas,
usually by county.
Other needed information which is best obtained at either the state (State
Department of Agriculture) or local (county) level includes:
4-8
-------
M
O
14-1
CO
CO
(U -H
4J >
•H -H
4J -H
C 4J
4-1
cfl
4-1
I
<•
cu
60
•H
4-9
-------
d
•3
o"
0)
•rl
CO
O
M
•S
>
1-1
O
4-1
O
ctf
CM
I
(U
^
3
t>0
4-10
-------
Acres of agricultural land in the area
Average percentage of time during a given year when fields are fallow and
the percentage of fields that are fallow. Fallow, in this context, means
agricultural land which is not under cultivation. Fallow fields are not
always bare soil, often having a vegetative cover of crop residue
consisting of either stubble or residue mulched into the ground. This
vegetative cover will significantly affect particulate emissions due to
wind erosion.
Type of crops planted—The residue (vegetative cover) left on a field is
closely related to the type of crops planted.
Average tractor speed during tilling.
Percentage of time that wind speed exceeds 12 mph (data obtained from
local U.S. Weather Bureau).
Once these variables have been determined, they can be applied to
Equations 4 and 5 of Table 4-1 to calculate fugitive dust emissions from
agricultural tilling operations and wind erosion of fallow fields. Equation
4, for agricultural tilling emissions is presented as:
Acres of farmland x l.ls
(S/5.5)
(PE/50V
while Equation 5, for wind erosion emissions of fallow fields is represented
by:
E = Acres of fallow field x 3400
where
fe) fe) fe)
(PE/50)'
E = emissions (pounds/yr),
s = soil silt content (%),
S = vehicle speed (mph),
PE = precipitation-evaporation index (see Figure 4-1),
e = surface erodibility (tons/acre-year), and
f = percentage of time wind speed exceeds 12 mph.
4-11
-------
An alternative version of the wind erosion equation is given by:
Es = AIKCL'V
where Es = suspended particulate fraction of wind erosion losses of
tilled fields, tons/acre-year,
A = portion of total wind erosion losses that would be measured as
suspended particulate, estimated to be 0.025,
I = soil erodibility, tons/acre-year,
K - surface roughness factor, dimensionless,
C = climatic factor, dimensionless,
L1 = unsheltered field width factor, dimensionless, and
V' = vegetative cover factor, dimensionless.
As an aid in understanding the meaning of this equation, "I" may be
thought of as the basic erodibility of a flat, very large, bare field in a
climate highly conducive to wind erosion (i.e., high wind speed and
temperature with little precipitation), and K, C, L1 and V as reduction
factors for a ridged surface, a climate less conducive to wind erosion,
smaller-sized fields, and vegetative cover, respectively. A more in-depth
explanation of each term is presented in Reference 4.
4.3.5 CONSTRUCTION ACTIVITIES
Construction activity can be divided into residential, industrial and
highway construction. A composite emission factor for these categories has
been developed which can be multiplied by the total area of active
construction to yield an estimation of fugitive construction emissions. The
State Highway Department or Department of Public Works should be able to
estimate the area (in acres or square miles) of highway and building
construction active during a given month of the year. Additional information
sources are:
Land Use Commissions
County Engineers
Local Assessors
Construction Associations
Once the active area of construction has been determined, emissions can be
estimated using Equation 6 of Table 4-1 which is:
E = 1.2 (active acres)
4-12
-------
The emissions in tons per month can be summed for the months during which
construction activities occur to obtain yearly emissions.
4.3.6 CATTLE FEED LOTS
Cattle feed lot emissions are of concern to agencies preparing
inventories in the Midwest and Great Plain States. Emissions from cattle feed
lots are based either on cattle feed lot area or the number of cattle in feed
lots (yearly throughput) in the survey area. Personnel at the State
Department of Agriculture should be able to provide accurate estimates of the
number and size of feed lots in the study area as well as their throughput
(number of cattle per year).
Once either of these parameters has been determined, emissions can be
estimated using Equation 7 of Table 4-1:
1000 head of cattle Q
E = x 8, or
yr
E = feed lot acres x 3
where E = emissions in tons/yr.
4.3.7 MISCELLANEOUS SOURCES
Miscellaneous anthropogenic and natural sources of fugitive particulate
emissions include blasting and demolition activities, and small industrial
process operations such as sawmills, auto body paint shops, wood and stone
working operations, small grain elevators, secondary metal, and fertilizer
mixing operations that are too small to be classified as point sources.
Agencies must prepare their own list of such miscellaneous sources. It is
essential that a careful determination be made by the agency as to the
magnitude and significance of any of these source activities in the agency's
jurisdiction. Emission estimates can then be made on the basis of existing
emission factor data for larger point sources, or by extrapolation of emission
data from related sources using best engineering judgment. For either method,
the agency must establish standard procedures for identifying and inventorying
these sources.
4.4 EMISSION CONTROLS
Several methods are used to control emissions from various area sources
of fugitive dust. Periodic wet suppression, oiling or the application of
chemical stabilizers are methods sometimes used to control unpaved roadway
emissions. Paving is, in most cases, the most cost-effective control method
and reduces fugitive particulate emissions by an order of magnitude or
greater. Fugitive dust emissions from paved roads can be effectively
controlled by sweeping, flushing, resurfacing and coating. Agricultural
emissions are controlled in some instances using vegetative stabilization,
wind brakes and/or wet suppression. Wet suppression and stabilization with
chemical binders are methods sometimes used to control emissions in
construction areas.
4-13
-------
Many area emission sources will be partially controlled. In such cases
engineering judgment must be relied upon to estimate the degree of control.
An estimate of control efficiency can then be incorporated into the
appropriate equation for calculating emissions.
Table 4-1 lists emission rates along with the variables (correction
factors) used in computing those factors. The emission rate, E, represents
uncontrolled emissions for the given fugitive dust source. To determine
controlled emission rates, the agency must estimate the extent to which
control is applied. For example, assuming that for county A:
Potential unpaved road emissions = 1000 tons/yr
Percent of total unpaved roadway controlled = 10 percent
Control efficiency = 70 percent
Then:
Controlled Emissions = (Uncontrolled Emissions) (1-XY)
where X = percent of roads controlled and
Y = control efficiency
and Controlled Emissons = (1000) (1 - (0.1) (0.7)) = 930 tons/year
As another example of calculation of emissions from unpaved roads, assume
that the following data have been obtained by the agency from the data sources
shown in Table 4-2.
EXAMPLE CALCULATION
Emission inventory for: County X
Unpaved Road Data
- Miles - 210
- Average daily traffic (ADT) - 700 vehicles/road mile/day
- VMT = Miles of road x ADT - 210 x 700 = 147,000 VMT/day
- Silt content(s) - 12 percent
- Average vehicle speed (S) - 35 raph
- Average vehicle weight (W) - 2.5 tons
- Dry days per year (d) - 230 days
Control—10 percent of roads are controlled (70 percent efficiency).
4-14
-------
_
Ji *~
VMT
5.<
yr
\0.8
E = (147,000) (365)
i)(f)
- (0.10) (0.70)
= 187,060,428 pounds per year (93,530 tons per year)
References for Chapter 4.0
1. Particulate Control for Fugitive Dust, EPA-600/7-78-071, U.S.
Environmental Protection Agency, Research Triangle Park, NC, April 1978.
2. Setting Priorities for Control of Fugitive Particulate Emissions from
Open Sources, EPA-600/ 7-79-186, U.S., Environmental Protection Agency,
Research Triangle Park, NC, August 1979.
3. Compilation of Air Pollution Emission Factors, APHE, U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina, October 1980.
4. Development of Emission Factors for Fugitive Dust Sources,
EPA-4 50/3-74-037, U.S. Environmental Protection Agency, Research Triangle
Park, NC, June 1974.
5. Emissions Inventory of Agricultural Tilling, Unpaved Roads and Airstrips,
and Construction Sites, EPA-450/3-74-085, U.S. Environmental Protection
Agency, Research Triangle Park, NC., November 1974. 41 p.
6. Fugitive Dust Emission Inventory Techniques. PEDCo — Environmental
Specialists, Inc. for presentation at the 67th Annual Meeting of the Air
Pollution Control Association, Denver, CO, June 9-13, 1974.
7. Emission Inventory/Factor Workshop, Volumes I and II. Prepared by the
Office of Air Quality Planning and Standards, U.S. Environmental
Protection Agency. Research Triangle Park, NC, September 13-15, 1977.
8. Quantification of Dust Entrainment from Paved Roadways, EPA-450/3-77-027,
U.S. Environmental Protection Agency, Research Triangle Park, NC, July
1977.
4-15
-------
5.0 VOLATILE ORGANIC COMPOUND (VOC) SOURCES
5.1 INTRODUCTION
This category includes operations/industries such as gasoline marketing,
dry cleaning, numerous types of surface coating, degreasing, pesticide use,
cutback asphalt, and solvents in household products.
This section presents general procedures for inventorying VOC sources and
provides specific guidance on the eight major categories of evaporative VOC
sources listed in Table 5-1. All area sources in these evaporative VOC
categories must be inventoried. However, the number of subcategories an
agency chooses to include in its inventory will depend on the needs of the
agency and inventory users. Special attention should be given to those
subcategories which are covered by existing or proposed regulations; e.g.,
ozone State Implementation Plans .
Each area source category listed in Table 5-1 will be described in more
detail later in this section. In some of these source categories, all of the
sources will meet the agency's definition of an area source. However, other
area source categories may include sources already in the point source
inventory file. Emissions from sources in the point source file must be
subtracted from the area source emission estimate to avoid "double-counting"
these facilities.
Additional sources of areawide VOC emissions not shown in Table 5-1.
include the fuel combustion and solid waste categories discussed previously.
Mobile source emissions of VOC, generally the largest VOC emitting category
(see Table 1-2) , are fully treated in Volume IV and are not addressed in this
volume.
5.2 GENERAL PROCEDURES
Five general procedures for inventorying evaporative VOC area source
categories are available. Each approach has distinct advantages and
disadvantages when inventorying area sources. The five procedures are (1) use
of point source inventorying methods, (2) use of local activity level data,
(3) apportioning state or national data, (4) per capita emission factors, and
(5) emissions-per-employee factors.^
5.2.1 USE OF POINT SOURCE INVENTORYING METHODS
There are several reasons for using point source methods to inventory
small sources that are maintained in the area source inventory. First, there
may be only a few sources within the geographical area being inventoried,
making it practical to inventory each source individually. Second, it may be
very difficult to correlate available activity level data for the sources to
their evaporative VOC emissions. Some bulk gasoline storage plants are a good
5-1
-------
TABLE 5-1. EVAPORATIVE VOC AREA SOURCE CATEGORIES
Source category
Emissions3
Procedure
recommended
Petroleum marketing
Tank truck unloading
Vehicle fueling
Storage tank losses
Tank truck transit losses
Degreasing
Dry cleaning
Surface coating
Industrial
Nonindustrial
Architectural coating
Auto body refinishing
Graphic arts
Commercial/consumer solvent use
Cutback asphalt
Pesticides
Use local activity level data
Point source methods
5 Point source methods
Survey
Emissions per employee
2 Survey
Per capita emission factor
10 Use local activity level data
Survey
Per capita emission factor
2 Per capita emission factor
5 Per capita emission factor
1 Local activity level data
1 Local activity level data
Apportion statewide data
aEmissions are indicated by an approximate relative scale. Ten is the
category with largest VOC emissions, 1 is the category(ies) with smallest
emissions, and the remaining numbers indicate the relative quantities of
emissions on a linear scale. The ratings are based on information contained
in References 2-4.
5-2
-------
example of small sources (emissions of about 10 to 70 tons/yr) that are small
in number and can readily be inventoried individually. The available activity
level indicator for the source category is gasoline sales which cannot be
easily correlated to the amount of gasoline throughput required to calculate
emissions for bulk plants. Therefore, agencies should contact the bulk plants
individually to obtain gasoline throughput data.
Another reason for using point source methods would be the availability
of sufficient data on individual small sources to directly calculate VOC
emissions. For example, records may be available from another agency which
show the location and amount of solvent handled by each dry cleaner within the
inventory area. At this point, the agency may decide whether an individual
point source record will be coded and maintained for each facility or whether
the resulting individual activity levels and emission estimates will be
collectively handled in the area source inventory.
Direct plant contact is also the best way to identify the type of VOC
used by a facility. Because many solvents, particularly those used for
degreasing,^ are considered nonreactive under atmospheric conditions, the
agency will want to identify those solvents and maintain them separately
within the inventory.
5.2.2 USE OF LOCAL ACTIVITY LEVEL DATA
Sometimes, local surveys have been performed that provide activity level
data. For example, local trade associations may have data on the amount and
types of architectural surface coating, or the amount and types of dry
cleaning or degreasing solvents used in an area. Tax, highway, and energy
'departments or other state or local agency records may provide activity level
estimates for other area source categories, including gasoline sales or
cutback asphalt use. Hence, the inventorying agency should survey various
local trade associations and agencies to determine the availability of
information that can be used for compiling an inventory of area sources.
5.2.3 APPORTIONING STATE OR NATIONAL DATA
If local data are not available, state or national data can be
apportioned to local areas. This may be done by indicators such as
population, number of employees or number of facilities. For example, if
pesticide application data are available only on a statewide basis from the
agricultural department, this data could be apportioned to counties by the
number of acres of agricultural land or the number of agricultural employees.
Major drawbacks of this approach are that additional data and resources
are needed to apportion activity level estimates to the local level, and
accuracy is lost in the process. If state and local data are not available,
then national data may have to be apportioned to the local inventory area.
Apportioning national data to the local level is less accurate than most
available methods and should be done only when absolutely necessary.
5-3
-------
The National Air Data Branch of EPA uses state and national totals from
various available publications to estimate area source emissions at the county
level for NEDS. Those interested in obtaining NEDS emission estimates for
particular area sources in specific counties should contact their EPA Regional
Office or the National Air Data Branch, MD-14, U.S. Environmental Protection
Agency, Research Triangle Park, NC 27711. There are only two evaporative
area source emission categories in NEDS: solvent purchased and gasoline
marketing. The NEDS area source estimates will not be as reliable and as
useful as estimates made by an agency using locale-specific information and a
much more extensive number of VOC categories.
5.2.4 PER CAPITA EMISSION FACTORS
Population per capita emission factors can be applied to some area source
categories that cannot be inventoried using one of the above procedures. As
an example, solvent evaporation from consumer and commercial products, such as
waxes, aerosol products and window cleaners, cannot be routinely determined by
the local agency from any local sources, nor will surveys generally yield such
information. The use of per capita factors is based on the assumption that,
in a given area, emissions can be reasonably associated with population. This
assumption is valid over broad areas for certain activities such as
drycleaning, architectural surface coating, and solvent evaporation from
household and commercial products. Per capita factors should not be developed
and used indiscriminately for sources whose emissions do not correlate well
with population.
5.2.5 EMISSIONS-PER-EMPLOYEE FACTORS
This procedure is similar to using population per capita emission
factors, except that emissions are correlated to the number of employees in
the source category. Emissions-per-employee factors are usually used to
estimate emissions from small industrial source categories for which an SIC
code has been assigned and for which employment data (typically by SIC) at the
local level are available. Because many facilities within the industrial
classifications of interest will be point sources of VOC emissions, it will be
possible to develop emissions-per-employee factors by SIC from data in the
point source,inventory, to account for emissions from small area sources.
This approach may also be used where the agency surveys a fraction of the area
sources within a given category. In this case, employment is used as an
indicator to "scale up" the inventory to account collectively for missing
sources and emissions in the area source file. Parameters other than
employment, such as sales data or number of facilities, can be used to develop
emission estimates.-5 However, employment is generally the most readily
available parameter.
5.3 SPECIFIC METHODS AND TECHNIQUES
Specific methods and techniques for inventorying eight major evaporative
VOC area source categories are presented below. These source categories
5-4
-------
include most but not all possible VOC sources. The inventorying agency should
inventory all area sources categories that may have significant VOC emissions
by applying the methods and techniques discussed in this chapter.
5.3.1 PETROLEUM LIQUIDS MARKETING AND STORAGE
The petroleum liquids marketing and storage area source category must be
carefully separated from the point source category of the same name. The area
source category usually covers VOC emissions from tank truck unloading and
service station operations; while bulk plants may be included under either an
area or a point source category. Gasoline is the petroleum liquid of primary
concern; however, aviation and marine fuels should also be considered. Diesel
fuel is not usually included because of its low volatility. The relative
magnitude of emissions from the marketing of gasoline is given in Table 5-2.
Emission factors for VOCs from gasoline loading operations and other petroleum
products are given in Section 4.4 of AP-42.->
TABLE 5-2. GASOLINE MARKETING AND STORAGE
Emission factor,3
Emission point lb/103 gal
Filling underground tank
Splash fill
Submerged fill
Stage I
Tank breathing losses
Vehicle refueling
With Stage II
Spillage
11.5
7.3
0.3
1.0
9.0
0.9
0.7
aThe user should refer to the current
edition of AP-42 to ensure the use of
the most up-to-date emission factors.
Source: Reference 5, AP-42, Table 4.4-4.
Gasoline can be purchased from service stations, auto repair garages,
parking garages, convenience stores, and similar types of businesses. In
addition, gasoline may be distributed to vehicles through various nonretail
outlets. Because outlets other than service stations account for roughly a
5-5
-------
quarter of all gasoline handled, care should be taken they are covered in the
area source inventory."5'
The method for determining emissions from petroleum liquid (gasoline)
marketing and storage is as follows:
1. Determine quantity of gasoline sold from tax data or transportation
planning agency data.
2. Determine the quantity of gasoline distributed through nonretail
outlets from local survey data, or use 30 percent of the quantity of
gasoline
3. Sum 1 and 2 to obtain total gasoline distributed.
4. Determine the percent of service stations equipped with submerged
fill underground storage tanks from local survey data, or use a
value of 90 percent, as suggested by recent studies. ~^
5. Consider whether Stage I and II vapor controls for tank and vehicle
filling, respectively, are required and, if so, determine the
percent of facilities with vapor control equipment installed and
operating.
6. Based on gasoline throughput determined in steps 1 and 2, above, and
emission factors in Table 5-2; determine VOC emissions from tank
truck unloading, tank breathing losses, vehicle refueling and
spillage.
The emission factors shown in Table 5-2 are AP-42 emission factors.
Because they are subject to revision, the agency should check with EPA before
using them to determine emissions from petroleum marketing. They are shown
here to illustrate the emission estimation procedure presented below.
From local activity level data and survey data determine:
Retail Gasoline: Retail gasoline consumption (10^ gal/yr).
Nonretail Gasoline: Nonretail gasoline consumption
(103 gal/yr).
Submerged Fill: Proportion of service stations equipped
with submerged fill storage tanks (convert
from percent).
Splash Fill: Proportion of service stations not equipped
with submerged fill or Stage I equipment.
5-6
-------
Stage I: Proportion of service stations equipped
with Stage I control equipment.
Stage II: Proportion of service stations equipped
with Stage II control equipment.
Bulk Plant: Bulk Plant throughput, 103 gal/yr.
The following equations apply:
Tank Truck = (Nonretail gasoline + retail gasoline)
Unloading Loss, (Submerged Fill x 7.3 + Splash Fill x
Ib/yr 11.5 + Stage I x 0.3).
Tank Breathing = (Nonretail gasoline + retail gasoline) x
Loss, Ib/yr 1.0.
Vehicle Refueling = (Nonretail gasoline + retail gasoline)
Loss, Ib/yr [(1-Stage II) x 9 + Stage II x 0.9].
Spillage Loss, = (Nonretail gasoline + retail gasoline) x
Ib/yr (0.7).
Area source VOC emissions from other petroleum liquids may be determined using
the above method and emission factors provided in Chapter 4.4 of AP-42.
5.3.2 DRY CLEANING
Virtually all commercial and self-service dry cleaning facilities are
area sources. Industrial dry cleaning facilities may be either point or area
sources. Dry cleaners emit one of three types of solvents: perchloroethylene
(70 percent of dry cleaning emissions), petroleum distillates or Stoddard
solvent (30 percent of emissions) or trichlorotrifluoroethane
(negligible).*•*>13 There are several methods of inventorying dry cleaning
emissions; two"widely applicable methods are given below.
Method 1 -
1. Send survey forms to a representative sample of dry cleaners
taken from the yellow pages of telephone directories. The data
to be collected are: number of employees, quantity of clothes
cleaned (ton/yr), type and the net amount of solvent used
(solvent purchased minuts solvent returned for recycle), and
normal operating schedule. Assume that all of the solvent used
is emitted, and check the survey values with emissions
calculated as the product of the AP-42 emission factors and the
quantity of clothes cleaned.
2. Project calculated emissions to the dry cleaning area source
category by either the number of nonpoint source employees in
SICs 7215, 7216, and 7218 (from County Business Patterns)14
or by number of area source facilities.
5-7
-------
Method 2 -
A less accurate method requiring less resources is to use per capita
emission factors as follows-. 3
0.36 Ib Stoddard/capita-yr from commercial plants
0.84 Ib perchloroethylene/capita-yr from commercial plants
0.30 Ib perchloroethylene/capita-yr from self service facilities
For this method, it is necessary to subtract out any emissions included in the
point source inventory.
5.3.3 DECREASING (SOLVENT CLEANING OPERATIONS)
There are basically three types of degreasers: small cold cleaners, open
top vapor degreasers, and conveyorized degreasers. According to recent
estimates, there are about 1,300,000 small cold cleaning units operating in
the U.S. Seventy percent of these units are devoted to maintenance of
servicing operations, including service stations, auto dealerships, and
miscellaneous repair stations, while the remaining 30 percent are devoted to
manufacturing operations. A typical cold cleaning unit emits approximately
one third metric ton of VOC per year. In contrast, typical open top vapor
degreasers and conveyorized degreasing units emit, respectively, 10 and 27
metric tons of VOC per year. These larger units are commonly used in the
metal working industry. The design and operation of each of these types of
degreasers will vary, as will emissions and the types of control measures
used. References 12 and 15 should be consulted for detailed descriptions of
processes and emissions from degreasing units.
A broad spectrum of organic liquids including petroleum distillates
(special naphthas), chlorinated hydrocarbons, ketones and alcohols are used in
solvent cleaning operations. Development of degreasing emission estimates is
complicated by a number of factors. First, some degreasers are large enough
to be considered point sources, and yet, a large fraction of all degreasers
will fall below any reasonable point source cutoff and thus must be accounted
for as area sources. Second, degreasing operations are not associated with
any particular industrial activity. Instead, degreasing of some sort may be
carried out in a wide variety of industries, including (1) metal working
facilities (e.g., automotive, electronics, appliances, furniture, jewelry,
plumbing, aircraft, refrigeration, business machinery, fasteners), (2)
nonmetal working facilities (printing, chemicals, plastics, rubber, textiles,
glass, paper, electric power), (3) maintenance cleaning operations (electric
motors, fork lift trucks, printing presses), and (4) repair shops (automobile,
railroad, bus, aircraft, truck, electric tool). Third, the practice of
solvent waste reprocessing at some degreasing facilities complicates the use
of material balance estimates of solvent loss. Fourth, the fact that some of
the VOC emissions associated with degreasing occurs at the solvent waste
disposal site complicates the location of emissions within the inventory
5-i
-------
area. Fifth, many of. the solvents used for degreasing are considered
photochemically nonreactive, and hence, must be excluded from an inventory of
reactive VOC emissions.^'^ Reactivity is defined as a measure of the rate
and extent with which a VOC will react in the presence of sunlight and
nitrogen oxides to form photochemical oxidants. The nonreactive VOCs are:
Methane
Ethane
1,1,1-Trichloroethane (methyl chloroform)
Methylene chloride
Trichlorofluoromethane (CFC 11)
Dichlorodifluoromethane (CFC 12)
Chlorodifluoromethane (CFC 22)
Trifluoromethane (FC 23)
Trichlorotrifluoroethane (CFC 113)
Dichlorotetrafluoroethane (CFC 114)
Chloropentafluoroethane (CFC 115)
Open top vapor (OTV) cleaners and conveyorized cleaners should be
included in the point source inventory whenever possible. These types of
equipment tend to be associated with industrial plants that are already
included in the point source inventory. Cold cleaners are smaller and will be
included primarily in the inventory of area sources. For open top vapor and
conveyorized cleaners that are not included in the point source, one of the
following methods may be used to project emissions for the category.
Method 1 -
Survey a sample population of facilities in SIC codes 25, 28, 30 and
33 through 39. The relative magnitude of VOC emission by SIC
category is shown in Table 5-3. The survey should establish the
number of each type of equipment operated; quantity and type of
solvent consumed; operating schedule; waste solvent disposal method;
and number of employees at the facility. (The inclusion or
exclusion of exempt solvent will be a decision of the agency based
on the purpose of the inventory.) Calculate an emissions per
employee or emissions per facility factor for each SIC code.
Multiply these factors by either the number of employees or the
number of facilities in each SIC - in each county (from County
Business Patterns).^ Point source emissions are subtracted from
the calculated total emissions.
Method 2 -
Instead of establishing a sample population through a survey, the
data on OTV and conveyorized cleaners in the point source inventory
can be used. The point source data could be used to establish
emissions per employee factors for each SIC code. County Business
Patterns data is used to project the area source category
emissions. This method may produce high estimates due to the
5-9
-------
TABLE 5-3. SOLVENT CLEANING EMISSIONS BY
SIC CATEGORY3
Release
SIC Group emissions
25 Furniture and Fixtures 1
28 Chemicals and Allied Products 1
30 Rubber and Miscellaneous
Plastic Products 1
33 Primary Metal Industry 9
34 Fabricated Metal Products 8
35 Machinery, Except Electric 10
36 Electric and Electronic Equipment 6
37 Transportation Equipment 1
38 Instruments and Related Products 1
39 Miscellaneous Manufacturing 1
75 Auto Repair, Services and Garages 2
alncludes point and area source category emissions.
bEmissions are indicated by an approximate relative linear
scale from 1 to 10; 1 indicating the least emissions
and 10 the most.
Source: Reference 16.
5-10
-------
potential bias of using data only from facilities large enough to be
included in the point source category. All point source emissions
should be subtracted from the area source projection.
VOC emissions from cold cleaners can be inventoried either by using
Method 1 (SIC 75 should be added) above, or through a per capita estimation
procedure. A 3 Ib/capita-yr emission factor is used for a reactive VOC
emission inventory.^ Cold cleaner emissions that are in the point source
inventory are subtracted out. Total VOC emissions are approximately 4
Ib/capita-yr of which 25 percent are 1,1,1-trichloroethane, methylene
chloride, and trichlorotrifluoroethane. -*
5.3.4 SURFACE COATING
Surface coating operations can be separated into two groups, industrial
and nonindustrial. Industrial surface coating operations for such products as
appliances, automobiles, paper, fabric and cans are usually point sources of
volatile organic compounds, although small area sources do exist. Because
there are no reliable area source inventory techniques for small industrial
surface coating operations, the agency should try to include as many sources
as possible in the point source inventory.* Nonindustrial surface coating
includes refinishing of automobiles and architectural coatings which are
better inventoried as area sources.
Architectural surface coatings (trade paints) are primarily used by
painting contractors and home owners. Sales and distribution data from
wholesale and retail suppliers of solvent-borne paints, varnishes and other
surface coatings provide the most accurate activity level data. Distributors
should be contacted directly, either through questionnaires or a telephone
survey. Necessary information includes quantities of solvent-borne and
water-borne coatings sold; and the average solvent content of each type of
coating sold. Also the quantity of thinning and cleaning solvents and their
densities should be obtained. To convert gallons (volume) of solvent to
pounds (mass), densities of 6.5 and 8.6 Ib/gal may be assumed for solvent-
borne and water-borne coatings, respectively. A density of 7.0 Ib/gal may be
assumed for thinning solvents. In the absence of solvent content data for
coatings, solvent-borne and water-borne coatings may be assumed to be 54 and
8 percent solvent by weight, respectively.*' However, solvent contents of
coatings vary greatly, and local data should be used if available. It is
assumed that all solvent in the coatings evaporates upon application. An
alternative method for estimating emissions that can be used in the absence of
local data, is the application of a national activity level factor of 4.6
Ib/capita-yr. •* Thinning and cleanup emissions are included in this factor.
One approach to inventorying automobile refinishing emissions is to use
an emissions-per-employee factor and to apply it to the number of employees in
SICs 7531 and 7535. Based on nationwide estimates of solvent loss from
automobile refinishing and employment in these two SICs, an average factor of
5-11
-------
2.6 ton/employee-year may be applied as an estimate of auto body shop
emissions in the area.18 Employment by SIC code is available at county
levels in County Business Patterns. *•*
An alternative is to use a per capita emission factor of 1.9
Ib/capita/year.^ Because auto body refinishing may be generally expected to
relate to human activity, such a population based approach will provide
reasonable emission estimates. All VOC emissions from auto body refinishing
are reactive.
5.3.5 GRAPHIC ARTS
The graphic arts or printing industry consists of approximately 40,000
facilities. About half of these establishments are inhouse printing services
in nonprinting industries. Printing of newspapers, books, magazines, fabrics,
wall coverings, and other materials is considered to be a graphic arts
application.
An emission factor of 0.8 Ib/capita/year is recommended for estimating
VOC emissions from small graphic arts facilities which emit less than 100 tons
per year. Graphic arts facilities which emit more than 100 tons of VOC per
year are excluded from this factor and are inventoried by point source
procedures. However, emissions from point sources emitting less than 100 ton
per year must be subtracted from the per capita derived emission totals. •*
All VOC emissions from this industry are considered reactive.^
5.3.6 COMMERCIAL/CONSUMER SOLVENT USE
Certain commercial/consumer uses of products containing VOC are not
easily quantified using questionnaires, surveys or other inventory procedures
yielding locale-specific emission estimates. Thus, a factor of 6.3
Ib/capita/year is recommended for estimating reactive VOC emissions from this
category.^ This factor includes the following commercial/consumer
subcategories:
Reactive VOC
Household products 2.0 Ib/capita/year
Toiletries 1.4 Ib/capita/year
Aerosol products 0.8 Ib/capita/year
Rubbing compounds 0.6 Ib/capita/year
Windshield washing 3.4 Ib/capita/year
Polishes and waxes 0.3 Ib/capita/year
Nonindustrial adhesives 0.3 Ib/capita/year
5-12
-------
Space deoderants 0.2 Ib/capita/year
Moth control 0.1 Ib/capita/year
Laundry treatment 0.1 Ib/capita/year
Total 6.3 Ib/capita/year
These factors are based on national estimates of solvent use in each of these
end use categories. Speciation data are available in references 4 and 19.
The major organic materials comprising this 6.3 Ib/capita/year factor are
special naphthas, alcohols, carbonyls and various other organics. Nonreactive
halogenated compounds used in aerosols and other products are excluded from
this factor.
It should not be inferred that the commercial/consumer factor is a
catchall estimate to account for deficiencies in point source or area source
inventories. Specifically, the factor does not include: small cold cleaning
degreasing operations; dry cleaning plants; auto refinishing shops;
architectural surface coating applications; graphic art plants; cutback
asphalt applications; and pesticides not used for home and garden
applications. These categories must be inventoried by point or area source
procedures and be tabulated separately.
5.3.7 CUTBACK ASPHALT PAVING
Cutback asphalt is a type of liquified road surface that is prepared by
blending or "cutting back" asphalt cement with various kinds of petroleum
distillates. VOCs are emitted to the atmosphere as the cutback asphalt cures
and as the petroleum distillate, used as the diluent, evaporates. The diluent
content of cutbacks ranges from 25 to 45 percent by volume, averaging 35
percent. Gasoline or naphtha is used as the diluent in "rapid cure" cutback
(RC), kerosene is used in "medium cure" cutback (MC), and low volatility fuel
oil type solvents are used in "slow cure" road oils (SC).20
The two major variables affecting both the quantity of VOC emitted and
the time over which emissions occur are (1) the type and (2) the quantity of
petroleum distillate used as diluent. As an approximation, long term
emissions from cutback asphalts can be estimated by assuming that 95 percent
of the diluent evaporates from rapid cure cutback asphalts, 70 percent from
medium cure (MC) cutbacks, and about 25 percent from slow cure asphalts, by
weight percent. These percentages are applicable in estimating emissions
occuring during the ozone season. Some of the diluent appears to be retained
permanently in the road surface after application.20
Because the use of cutback asphalts varies so much from area to area,
local records should be accessed to determine usage in the area of concern.
Data should be obtained from the state or local highway department or highway
contractors on the quantity of each type of cutback applied, as well as the
diluent content of each. From these data, the equations or tables of
5-13
-------
AP-425 can be used to compute long term solvent evaporation. If the diluent
content is not known by the local highway department personnel, default values
of 25, 35, and 45 percent can be assumed for slow cure, medium cure, and rapid
cure cutbacks, respectively.
5.3.8 PESTICIDES
Pesticides broadly include any substances used to kill or retard the
growth of insects, rodents, fungi, weeds, or microorganisms. Pesticides fall
into three basic categories: synthetics, nonsynthetics (petroleum products),
and inorganics.
Formulations are commonly made by combining synthetic pesticides with
various petroleum products. The synthetic pest killing compounds in such
formulations are labeled as "active" ingredients, and the petroleum product
solvents acting as vehicles for the active ingredients are labeled "inert."
Neither of these toxicological designations should be interpreted as
indicators of photochemical reactivity. Inorganic pesticides are not of
interest in the inventory, since they contain no organic fraction.^1»22
Local, state and federal departments of agriculture (including branches
concerned with forest pests control) should be contacted to determine the
quantities and types of pesticides applied within the inventory area. The
quantity of inorganics, should first be eliminated from the above total.
Then, as a crude estimate, the remaining synthetic and nonsynthetic total
should be multiplied by a factor of 0.9 to estimate the amount that evaporates
and can be considered photochemically-reactive VOC.
Pesticide application in agricultural areas may range from 2 to 5
Ib/yr-harvested acre.20 This use includes both synthetic and nonsynthetic
material in the pesticide formulation. These factors should be applied as a
check on the figures determined from local sources.
Pesticide use for nonagricultural applications should be determined by
contacting appropriate state or local agencies, including local public health
departments, parks departments, highway departments, or private concerns such
as utilities, exterminators, and landscapers. These groups will know the
extent of pesticide application for insect control and weed killing, in
addition to that used in agricultural applications. The same types of data
are obtained and the same procedures followed for estimating evaporative VOC
as are suggested for agricultural pesticides. Commercial/consumer pesticide
use is quantified under the subcategory headings of household products and
moth control in Section 5.3.6. Commercial/consumer pesticide usage is
reported to be less than 0.25 lb/capita/year.^
5-14
-------
References for Chapter 5.0
1. Emission Inventory Requirement8 for 1982 Ozone State Implementation
Plans, EPA-450/4-80-016, U.S. Environmental Protection Agency,
Research Triangle Park, NC, December 1980.
2. Procedures for the Preparation of Emission Inventories for Volatile
Organic Compounds, Volume 1, Second Edition, EPA-450/2-77-028, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
September 1980.
3. Development of Hydrocarbon Emission Inventory for Massachusetts,
EPA-901/9-79-005, U.S. Environmental Protection Agency, Research
Triangle Park, NC, September 1979.
4. End Use of Solvents Containing Volatile Organic Compounds,
EPA-450/3-79-032, U.S. Environmental Protection Agency, Research
Triangle Park, NC, May 1979.
5. Compilation of Air Pollutant Emission Factors, Third Edition and
Supplements, AP-42, U.S. Environmental Protection Agency, Research
Triangle Park, NC, October 1980.
6. Hydrocarbon Control Strategies for Gasoline Marketing Operations,
EPA-450/3-78-017, U.S. Environmental Protection Agency, Research
Triangle Park, NC, April 1978.
7. Design Criteria for Stage I Vapor Control Systems for Gasoline
Service Stations, U.S. Environmental Protection Agency, Research
Triangle Park, NC, November 1975.
8. Emission Inventory for Enforcement of New Source Review Policies,
EPA Contract No. 68-01-4148, Pacific Environmental Services, Inc.,
Santa Monica, CA, April 1979.
9. Florida Oxidant SIP Assistance, Phase I: VOC Emissions Inventory,
EPA-904/9-79-029a, Monitoring and Data Analysis Division, U.S.
Environmental Protection Agency, Atlanta, GA, Feburary 1979.
10. Emission Inventories for Urban Airshed Model Application in Tulsa,
Oklahoma, EPA-^450/4-80-021, Monitoring and Data Analysis Division,
U.S. Environmental Protection Agency, Research Triangle Park, NC,
September 1980.
11. Tampa Bay Photochemical Oxidant Study; Assessment of Anthropogenic
Hydrocarbon and Nitrogen Dioxide Emissions in the Tampa Bay Area,
EPA-904/9-77-016, U.S. Environmental Protection Agency, Atlanta, GA,
September 1978.
5-15
-------
12. Control Techniques for Volatile Organic Emissions from Stationary
Sources, EPA-450/2-78-022, U.S. Environmental Protection Agency,
Research Triangle Park, NC, May 1978.
13. Lamason, W. H. "Technical Discussion of Per Capita Emission Factors
and National Emissions of Volatile Organic Compounds for Several
Area Source Emission Inventory Categories," Monitoring and Data
Analysis Division, U.S. Environmental Protection Agency, Research
Triangle Park, NC, July 1980. Unpublished.
14. County Business Patterns, U.S. Department of Commerce, Bureau of the
Census, Washington, DC, Annual publication.
15. Control of Volatile Organic Emissions from Solvent Metal Cleaning,
EPA-450/2-77-022, U.S. Environmental Protection Agency, Research
Triangle Park, NC, November 1977.
16. Volatile Organic Compound Emissions from Solvent Cleaning Operations
in the State of Illinois, EPA 905-4-80-008, U.S. Environmental
Portection Agency, Region V, Chicago, IL, January 1981.
17. Emission Inventory/Factor Workshop, Volume II, EPA-450/3-78-042b,
U.S. Environmental Protection Agency, Research Triangle Park, NC,
May 1978.
18. Written communication from Bill Lamason, to Chuck Mann, Monitoring
and Data Analysis Division, U.S. Environmental Protection Agency,
Research Triangle Park, NC, September 1980.
19. Volatile OrganicCompound Species Data Manual, EPA-450/4-80-015,
U.S. Environmental Protection Agency, Research Triangle Park, NC,
July 1980.
20• Control of Volatile Organic Compounds from Use of Cutback Asphalt,
EPA-450/2-77-037, U.S. Environmental Protection Agency, Research
Triangle Park, NC, December 1977.
21. Leung, Steve, et al. "Air Pollution Emissions Associated with
Pesticide Applications in Fresno County," California Air Resources
Board Report No. 77-E-02, Eureka Laboratories, Inc., Sacramento, CA,
December 1978.
22. Wiens, F. J. "A Methodology for Reactive Organic Gas Emissions
Assessment of Pesticide Usage in California," (Draft Interim
Report), California Air Resources Board, 1977.
5-16
-------
6.0 PRESENTATION OF AREA SOURCE EMISSION INVENTORIES
6.1 INTRODUCTION
Area sources, as previously defined, are those stationary facilities too
small, and/or too numerous to be surveyed individually. Emission inventory
data on these sources are obtained, recorded and presented on a collective
basis. Source categories, not individual sources, are therefore the
level of concern when reporting emission data. The major area source
categories have been discussed in Chapters 2 through 5 of this volume. For
data handling and evaluation purposes, these categories are often further
subdivided according to the origin of the areawide emissions. Fugitive dust
emissions, for example, can be attributed to subcategories such as
agricultural activity, construction activity, unpaved roads or natural
sources. Specific data presentation techniques will utilize these
subcategories in displaying emission levels. Most of the methods of data
presentation discussed in Volume I, Chapter 6, are useful in presenting area
source data. However, specific techniques that relate the inventory area
(county, AQCR, SMSA) to emissions from area source categories type and the
pollutant(s) of concern are provided in this section. The specific uses of
the emission inventory will determine the data maintained in the file and the
focus of data presentation.
6.2 SPECIFIC PRESENTATION TECHNIQUES
Tabulated summaries are the most common method of presenting area source
data. Examples of this technique for various area source category/pollutant
combinations are presented in Tables 6-1 through 6-4. Table 6-1 is a
statewide inventory summary of area and mobile source emissions. Major area
source categories are broken down into several subcategories. Overall, this
table indicates the source of each pollutant and identifies the level of
contribution of each category to emissions. This type of presentation is not
only informative to the general public, but is also useful to air quality
planners and management by indicating where resources should be concentrated.
Table 6-2 presents more specific area source data. These data are only for
one AQCR and only for emissions from one subcategory, commercial-institutional
incinerators. By displaying emissions on a county basis, this summary
facilitates comparisons between counties and identifies potential problem
areas associated with incineration. Table 6-3 demonstrates another use of the
tabulated summary. This list of reactive organic emissions in an urban area
was made to note relative changes in these emissions during the summer
months. This type of comparison is useful for pollutants which may exhibit a
seasonal variance in emissions due to temperature and/or activity level
changes. Table 6-4 illustrates the use of summary tables for comparing base
year emissions with projected emissions. Emission projections are made
assuming no additional controls (Column 2) and assuming additional regulatory
controls adopted as part of the SIP (Column 3).
6-1
-------
TABLE 6-1. STATE OF NEW HAMPSHIRE 1985 AREA SOURCE
POLLUTANT EMISSIONS (TONS/YEAR)3
FUEL COMBUSTION
Residential
Anthracite Coal
Bituminous Coal
Distillate Oil
Natural Gas
Wood
Bituminous Coal
Distillate Oil
Residual Oil
Natural Gas
Industrial
Bituminous Coal
Distillate Oil
Residual Oil
Natural Gas
Wood
Total Fuel Combustion
TRANSPORTATION
Highway
Light-duty
Heavy-duty
Diesel
Off-Highway
Gasoline
Diesel
Rail
Vessel
Gasoline
Diesel
Aircraft
Comrae re i a 1
Civil
Military
Total Transportation
MISCELLANEOUS
Evaporative Losses
Retail Gasoline
Solvent Evaporation
Solid Waste Disposal
All
Fires and Open Burning
Structure Fires
Forest Fires
Fugitive Emissions
Dirt Roads
Dirt Airstrips
Construction
Wind Erosion
Land Tilling
Total Miscellaneous
STATE TOTAL
Particulate
Matter
16
0
276
21
1,760
0
76
39
14
161
64
197
8
4,360
6,990
2,000
649
429
147
334
0
0
1
4
58
270
3 , 890
0
0
309
194
39
613,000
27
78,600
68
535
693,000
704,000
Sulfur
Oxides
35
0
3,180
1
106
0
1,100
531
1
65
920
2,680
0
262
8,880
612
80
)64
77
299
0
5
1
6
11
51
1,510
0
0
60
0
0
0
0
0
0
0
60
10,400
Nitrogen
Oxides
5
0
1,990
172
706
0
840
111
173
13
703
562
143
1,740
7,160
5,300
3,250
2,990
1,670
3,700
0
20
11
61
52
129
17,200
0
0
74
17
9
0
0
0
0
0
100
24,500
Hydro-
carbons
4
0
110
17
1,410
0
38
2
12
1
32
9
2
3,490
5,120
6,330
1,410
457
4,720
406
0
683
3
80
255
625
15,000
5,070
46,700
458
50
55
0
0
0
0
0
52,300
72,400
Carbon
Monoxide
143
0
552
43
1,410
0
191
9
29
2
160
47
14
3,490
6,090
28,400
20,600
2,560
53,500
1,040
0
2,170
4
166
1,460
671
111,000
0
0
1,290
439
318
0
0
0
0
0
2,050
119,000
aThis Table is presented to provide a format example.
should not necessarily be considered typical.
Source; Reference 1.
Data contained herein
6-2
-------
TABLE 6-2. SOLID WASTE COMMERCIAL-INSTITUTIONAL INCINERATION EMISSIONS
(TONS/YEAR) IN AQCR 70 FOR 1973a
County
Missouri
Franklin
Jefferson
St. Charles
St. Louis
St. Louis City
Illinois
Bond
Clinton
Madison
Monroe
Randolph
St. Clair
Washington
Part.
3.21
6.05
5.47
50.00
29.86
0.74
1.52
13.30
0.95
1.63
15.09
0.74
SOX
0.38
0.73
0.66
6.00
3.58
0.09
0.18
1.60
0.11
0.20
1.81
0.09
NOX
0.58
1.09
0.98
9.00
5.38
0.13
0.27
2.40
0.17
0.29
2.72
0.13
EC
2.57
4.84
4.37
40.00
23.89
0.59
1.22
10.68
0.76
1.30
12.07
0.59
CO
5.13
9.67
8.75
80.00
47.78
1.18
2.44
21.37
1.51
2.61
24.14
1.18
aThis Table is presented to provide a format example.
Data contained herein should not necessarily be con-
sidered typical.
Source: Reference 2
6-3
-------
TABLE 6-3. REACTIVE ORGANIC EMISSION, TAMPA BAYa
Emissions
Summer
Source Category
Gasoline-powered vehicles
Exhaust emissions
Evaporative emissions
Solvent evaporative losses
Petroleum product
evaporation
Storage and transport
Gasoline station losses
Petroleum refineries
Solid waste disposal
Manufacturing
Stationary fuel combustion
Carbon black production
Aircraft
Diesel-powered vehicles
Vessels
Remainder unlisted
Total
MT/yr
42,400
25,400
17,000
8,800
7,100
5,800
0
500
2,700
700
0
800
1,400
3,000
1,600
74,800
%
(61)
37
24
13
1
9
0
1
4
1
0
1
2
5
2
100
Annual
MT/yr
41,400
26,500
14,900
8,800
6,100
5,400
0
500
2,700
700
0
800
1,400
3,000
1,600
72,400
%
(61)
39
22
14
1
8
0
1
4
1
0
1
2
5
2
100
aThis Table is presented to provide a format example. Data
contained herein should not necessarily be considered typical.
Source: Reference 3.
6-4
-------
TABLE 6-4. SUMMARY TABLE OF REACTIVE VOC EMISSIONS FOR
GEOGRAPHICAL AREA3
Baseline
Base Year Projection SIP Strategy
STORAGE, TRANSPORTATION AND
MARKETING OF VOC
Oil and Gas Production & Processing
Gasoline and Crude Oil Storage
Synthetic Organic Chemical Storage
& Transfer
Ship and Barge Transfer of VOC
Barge and Tanker Cleaning
Bulk Gasoline Terminals
Gasoline Bulk Plants
Service Station Loading (Stage I)
Service Station Unloading (Stage II)
Others (Specify)
INDUSTRIAL PROCESSES
Petroleum Refineries
Lube Oil Manufacture
Organic Chemical Manufacture
Inorganic Chemical Manufacture
Fermentation Processes
Vegetable Oil Processing
Pharmaceutical Manufacture
Plastic Products Manufacture
Rubber Tire Manufacture
SBR Rubber Manufacture
Textile Polymers & Resin Manufacture
Synthetic Fiber Manufacture
Iron and Steel Manufacture
Others (Specify)
INDUSTRIAL SURFACE COATING
Large Appliances
Magnet Wire
Automobiles
Cans
Metal Coils
Paper
Fabric
Metal Wood Products
Miscellaneous Metal Products
Plastics Parts Painting
Large Ships
Large Aircraft
Others (Specify)
1980
Point
Area
Attainment
year
Point
Area
Attainment
year
Point
Area
(continued)
6-5
-------
TABLE 6-4 (continued)
Baseline
Base Year Projection SIP Strategy
NONINDUSTRIAL SURFACE COATING
Architectural Coatings
Auto Refinishing
Others (Specify)
OTHER SOLVENT USE
Degreasing
Dry Cleaning
Graphic Arts
Adhesives
Cutback Asphalt
Solvent Extraction Processes
Consumer/ Comme re ial Solvent Use
Others (Specify)
OTHER MISCELLANEOUS SOURCES
Fuel Combustion
Solid Waste Disposal
Forest, Agricultural, and Other
Opqn Burning
Pesticide Application
Waste Solvent Recovery Processes
Stationary Internal Combustion Engines
MOBILE SOURCES
Highway Vehicles
Light-Duty Automobiles
Light-Duty Trucks
Heavy-Duty Gasoline Trucks
Heavy-Duty Diesel Trucks
Motorcycles
Off-Highway Vehicles
Rail
Aircraft
Vessels
Total
1980
Point
i
Area
1
Attainment
year
Point
Area
!
Attainment
year
Point
Area
aKilograms per day (kg/day) for a typical summer weekday.
Source: Reference 4.
6-6
-------
Another common presentation technique is the pie chart, shown in Figure
6-1. Pie charts are useful for presenting data to audiences who do not have
the time or the expertise to review large amounts of tabulated data. Pie
charts summarize data in a direct manner that facilitates quick comparisons.
Referring to Figure 6-1, the reader can quickly see that the fugitive
particulate emission problem in this survey area is largely attributable to
unpaved roads. This type of graphical display would be especially useful, for
example, if the agency is presenting emission data at a public hearing, in
support of proposed fugitive emission control regulations. For pie charts,
absolute quantities of emissions are not as important as relative amounts.
General display techniques of the type identified in Volume I, Chapter 6,
may also be used for area source data. Bar charts, line charts and time
series charts can all be used to highlight and present data in various ways.
Emission density plots of the type shown in Figure 6-2 are useful for a
variety of air quality projects. They can be used to pinpoint area source
contributions to local air quality problems, help in siting of ambient
monitoring stations and serve as a useful tool in air quality maintenance area
planning. Area source density maps, when added to similar overlays for point
and mobile source densities, graphically display the relative source
contributions to local air quality levels.
Display techniques are frequently used by agencies in presenting and
analyzing temporal and spatial emissions variations. A plot of relative
temporal activity levels as shown in Figure 6-3. This series of time charts
presents the hourly, daily, and seasonal activity of one area source
subcategory, agricultural tilling. This type of activity level plot is used
to temporally resolve annual emission rates and to correlate activity levels
with air quality levels.
Zoning maps are often used to spatially allocate area source emissions to
grids. A representative urban zoning map is presented in Figure 6-4. These
maps are available from local planning and zoning boards. Fuel use, solid
waste disposal, fugitive dust and volatile organic compound emissions are all
allocated on the basis of land use. Activity levels are allocated by
superimposing the grid (adjusted to the proper scale) onto the zoning map to
determine the land area being used for a given purpose (i.e., residential,
commercial/institutional, industrial) within each grid square. Grid square
emissions per category are then calculated using procedures previously
outlined in this volume.
Area source emissions data may be presented in any format that is
compatible with the end use of the data. All emission inventory summaries can
be limited to one page, and no one technique is necessarily better than
another. The compiler of the inventory summary should take into account the
environmental awareness of the audience before selecting any specific method.
6-7
-------
- OTHER
(FEEDLOTS.LTO CYCLES, MINERAL TAILINGS)
3.5 %
CONSTRUCT!
SITES
8%
EROSION
OF
CROPLAND
7.3 %
AGGREGATE
STORAGE
7.3%
UNPAVED ROADS
60%
PAVED
ROADS
8%
Figure 6-1. The distribution of fugitive particulate emissions
in a survey area.
6-8
-------
a
n
Z >- o o
o a
> o o o o
' 04 -
\—
>—.4
en
z
UJ
a
cr
xz
ota
cr—'
tn
ao z:
z:uj
3
—10.
o
-------
Source Type: Agricultural Tilling
7
±
01 2345678 9 10 1112 13 14 15 161718 19 2021 2223
Hour of Day
20
15
10
Mon Tue
Wed Thu Fri
Day of Week
Sat Sun
JO
50
45
40
35
30
25
20
15
10
5
/ /
//
//
it
f
/\
Zr \
j. \
/ /x\
/ / ^ ^
//
\
\\.--**"
\ -^,^>>
^.-^"'
— Illinois
•— Missouri
Winter
Spring Summer
Season of Year
Fall
Source: Reference 6.
Figure 6-3. Percentage of total daily, weekly, and annual
agricultural tilling.
6-10
-------
CHICAGO ZONING ORDINANCE
_J1 I L_
1 r~
SEC r T 3tN HUE
t±J t±J CD a CZ]
RESIDENCE DISTRICTS
Rl SINGLE - FAULT RESIDENCE DISTRICT
RZ SHKLE-FUM.Y NESBENCE USTRCT
R3 CCNERAL RCSBCNCI DISTRICT
R4 C£«Ml RESNXNCC DISTRICT
R5 GENERAL RESUENCE DISTRICT
R6 CENERN. RESIDENCE DISTRICT
R7 GENERAL RESIDENCE DISTRICT
R8 GENERAL RESIDENCE DISTRICT
Source: Reference 5.
Bl-
82-
B3-
84-
85-
BUSINESS DISTRICTS
TO BI-S LOCAL RETAIL DISTRICTS
TO 82-5 RESTRICTED RETAL DISTRICTS
TO B3-S GENERAL RETAIL DISTRICTS
TO B4-5 RESTRICTED SERVICE DISTRICTS
TO 85-5 GENERAL SERVICE DISTRICTS
BS-6 AW BC-? RESTRICTED CENTRAL BUSINESS DISTRICTS
B7-S TO 87-7 GENERAL CENTRAL BUSINESS DISTRICTS
COMMERCIAL DISTRICTS
Cl-l TOCI-5 RESTRICTED COHMCftCUL DISTRICTS
C2-I TO C2-5 GENERAL COMMERCIAL OBTMCTS
CJ-I TO C3-7 CtMMCRCIAL-MANUFACTUMNC OBTRKTS
C4 MOTOR FREIGHT TERMINAL DISTRICT
MANUFACTURING DISTRICTS
Ml-l TO Ml-5 RESTRICTED MANUFACTMNG HSTRKTS
M2-I TO M2-5 GENERAL MANUFACTURING DISTRICTS
MJ-I TOH3-5 HEAVY MANUFACTURMG DISTRICT
Figure 6-4. Example of Complex Zoning (from City of Chicago Zoning Ordinance).
6-11
-------
iReferences for Chapter 6.0
1. Area Source Emission Inventory for AQMP Development in New Hampshire,
EPA 901/9-77-003, U.S. Environmental Protection Agency, Research Triangle
Park, NC, December 1977.
2. Residential and Commercial Area Source Emission Inventory Metholology for
the Regional Air Pollution Study, EPA 450/3-75-078, U.S. Environmental
Protection Agency, Research Triangle Park, NC, September 1975.
3. Seasonal Variations in Organic Emissions for Significant Source of
Volatile Organic Compounds, EPA 450/3-78-023, U.S. Environmental
Protection Agency, Research Triangle Park, NC.
4. Final Emission Inventory Requirements for 1982 Ozone State Implementation
Plans, EPA 450/4-80-016, U.S. Environmental Protection Agency, Research
Triangle Park, NC, December 1980.
5. Argonne National Laboratory, Emission Density Zoning Guidebook,
EPA-450/3-78-048, U.S. Environmental Protection, Research Triangle Park,
NC, September 1978.
6. Regional Air Pollution Study: Emission Inventory Summarization, EPA
600/4-79-004, U.S. Environmental Protection Agency, Research Triangle
Park, NC, January 1979.
6-12
-------
TECHNICAL REPORT DATA
(Please read Instructions en the reverse before completing)
1 REPORT NO.
EPA-650/4-81-Q26C
4. TITLE AND SUBTITLE
Procedures for Emission Inventory Preparation
Volume III: Area Sources
5. REPORT DATE
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Monitoring and Data Analysis Division
Office of Air Quality Planning and Standards
9 PERFORMING ORGANIZATION NAME AND ADDRESS
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
3. RECIPIENT'S ACCESSION NO.
September 1981
8. PERFORMING ORGANIZATION REPORT NO
10. PROGRAM ELEMENT NO.
11 CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
EPA Project Officer: A. A. MacQueen
16. ABSTRACT
Procedures are described for compiling the complete comprehensive emission
inventory of the criteria pollutants and pollutant sources. These procedures
described are for use in the air quality management programs of state and local
air pollution control agencies.
Basic emission inventory elements--planning, data collection, emission esti-
mates, inventory file formatting, reporting and maintenance—are described.
Prescribed methods are presented; optional methods are provided. The procedures
are presented in five (5) volumes:
Volume I, Emission Inventory Fundamentals
Volume II, Point Sources
Volume III, Area Sources
Volume IV, Mobile Sources
Volume V, Bibliography
KB / WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
Emission Inventory
Inventory
Source Inventory
Emissions Source
Emissions Files Formatting
Questionnaire
Air Quality Management
Area Sources
V) IDENTIFIERS/OPEN ENDED TERMS C. COSATI Held/Group
8 DISTRIBUTION STATEMENT
i9 SECUF-TY CLAS?
21. NC OF PAGES"
' 106
~2. PRICE
-------
------- |