United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EPA-450/4-83-010
March 1983
,Air
11.2,
Fugitive Dust
Sources
An AP-42 Update Of
Open Source Fugitive
Dust Emissions
-------
EPA-450/4-83-010
Section 11.2, Fugitive
Dust Sources
An AP-42 Update Of Open
Source Fugitive Dust Emissions
By
Midwest Research Institute
Kansas City, Missouri
Contract No. 68-02-3177
EPA Project Officer: Frank M. Noonan
Prepared For
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air, Noise and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, NC 27711
March 1983
-------
This report has been reviewed by the Office of Air Quality Planning and
Standards, U.S. Environmental Protection Agency, and approved for publica-
tion as received from Midwest Research Institute, Kansas City, Missouri.
Approval does not signify that the contents necessarily reflect the views
and policies of the U.S. Environmental Protection Agency, neither does men-
tion of trade names or commercial products constitute endorsement or recom-
mendation for use.
-------
CONTENTS
3.0
4.0
5.0
3.2
Candidate
4.1
4.2
4.3
Introduction
Methodology for Identification of Candidate Emission Factors.
2.1 Literature search
2.2 Screening criteria
2.3 Final selection
Emission Factor Quality Rating Scheme
3.1 Rating of test data
Rating of emission factors
Emission Factors
Section 11.2.1 - Unpaved Roads
Section 11.2.2 - Agricultural Tilling
Section 11.2.3 - Aggregate Storage Piles and
Materials Handling
Section 11.2.5 - Paved Roads
Factors Recommended for AP-42
Criteria for recommendations
Recommendations
Emission factor applicability
4.4
Emission
5.1
5.2
5.3
References
1
3
3
3
3
5
5
5
9
9
13
16
19
21
21
21
30
34
111
-------
1.0 INTRODUCTION
In assessment and control of air pollution, there is a critical need
for reliable and consistent data on the quantity and characteristics of emis-
sions from the numerous sources that contribute to the problem. The large
number of individual sources and the diversity of source types make con-
ducting field measurements of emissions impractical source by source, at
each point of release. The only feasible method of determining pollutant
emissions for a given community or area is to make general emission esti-
mates typical of each of the source types.
Calculation of the estimated emission rate for a given source requires
data on source extent, uncontrolled emission factor and control efficiency.
The mathematical expression for this calculation is as follows:
R = Me (1 - c) (1)
where R = mass emission rate
M = source extent
e = uncontrolled emission factor, i.e., rate of uncontrolled
emissions per unit of source extent
c = fractional efficiency of control
The emission factor is an estimate of the rate at which a pollutant is re-
leased to the atmosphere divided by the level of source activity.
The document "Compilation of Air Pollutant Emission Factors" (AP-42),
published by the U.S. Environmental Protection Agency (EPA) since 1972, is
a compilation of emission factor reports for the most significant emission
source categories. Supplements to AP-42 have been published for both new
emission source categories and for updating existing emission source cate-
gories, as more information about sources and control of emissions has be-
come available.
Because the national effort to control industrial sources of pollution
has focused on discharge from stacks, ducts or flues, most of the emission
factors reported in AP-42 apply to ducted emission sources. Recently how-
ever, evidence has mounted which indicates that fugitive (nonducted) emis-
sions contribute substantially to the impact of industrial operations and
in some industries may be greater than the stack emissions. This points to
the need for emission factors which are applicable to fugitive emissions.
Industrial sources of fugitive particulate emissions may be divided
into two classes—process sources and open dust sources. Process sources
are fully or partially enclosed operations that alter the chemical or phys-
ical properties of a feed material. Examples of process sources are crush-
ers, sintering machines, and metallurgical furnaces. Open dust sources are
those that entail generation of emissions of solid particles by the forces
-------
of wind and machinery acting on exposed materials. Open dust sources in-
clude open transport, storage and transfer of raw intermediate and waste
aggregate materials.
Emission factors for sources of primary particulate emissions have
been compiled in AP-42. However, only a small portion of these values
apply to either process fugitive emissions or open dust sources. Section
11.2 of AP-42 currently provides open dust source emission factors for
paved and unpaved roads, agricultural tilling, aggregate storage piles and
heavy construction operations.
Because of the recognized importance of open dust sources, largely de-
termined from recent receptor-oriented investigations of source culpability,
the rate of test data accumulation for these sources has increased substan-
tially. For this reason most of the emission factors reported in AP-42 for
open dust sources are in serious need of updating.
The purpose of this report is to present background information in
support of a revised AP-42 Section 11.2, Fugitive Dust Sources, incorporat-
ing emission factors for open dust sources. This report is organized by
section as follows:
Section 2 - Methodology for identification of candidate emission factors
Section 3 - Emission factor quality rating scheme.
Section 4 - Candidate emission factors.
Section 5 - Emission factors recommended for AP-42.
-------
2.0 METHODOLOGY FOR IDENTIFICATION
OF CANDIDATE EMISSION FACTORS
2.1 Literature Search
The first step in the identification of candidate open dust source
emission factors for Section 11.2 was a search of the published literature.
The literature search was begun by a review of MRI's in-house library of
documents relating to fugitive dust emissions and emission factor develop-
ment. A supplemental computerized literature search was performed to verify
that all pertinent documentation was indeed maintained at MRI. The search,
performed by EPA Library Services, examined Chemical Abstracts, Engineering
Index, Environmental Abstracts, and National Technical Information Service
files.
2.2 Screening Criteria
In order to reduce the amount of literature which dealt in some way
with fugitive dust emissions in the iron and steel industry to a final
group of references pertinent to this update, five criteria were used:
1. The information in the reference document must deal with actual
emission factor development. Many documents discuss emission
factors but do not derive them.
2. Source testing must be part of the referenced study. Some
reports develop emission factors by applying assumptions to exis-
ting factors.
3. The referenced study must deal with open dust source emissions.
Process fugitive emissions such as crushing, screening, and
grinding are not pertinent to this investigation.
4. The document must constitute the original source of test data.
For example, a convention or symposium paper was not included if
the original study was already contained in a previous document.
5. The results of the referenced study must not be presently incor-
porated in AP-42. The purpose of this study is to recommend up-
dating AP-42 with research results not previously contained in
AP-42. If possible, however, new test data are to be combined
with previous data (used to develop the current AP-42 emission
factor) in deriving an updated emission factor.
2.3 Final Selection
A final set of reference materials was collected after scrutinizing
all possible reports, documents, and information with the four criteria
stated above. Table 1 lists the final set of primary reference documents.
This set of documents will be reviewed with the criteria stated in Section 3
to determine the candidate emission factors listed in Section 4.
-------
TABLE 1. PRIMARY LIST OF TEST REPORTS
1. G. Jutze and K. Axetell, Investigation of Fugitive Dust, Volume I -
Sources, Emissions, and Control, EPA-450/3-74-036-a, U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina, June 1974.
2. R. J. Dyck and J. J. Stukel, "Fugitive Dust Emissions from Trucks on
Unpaved Roads," Environmental Science and Technology. 10(10): 1046-1048,
October 1976.
3. R. Bonn, et al.. Fugitive Emissions from Integrated Iron and Steel
Plants, EPA-600/2-78-050, U.S. Environmental Protection Agency, Re-
search Triangle Park, North Carolina, March 1978.
4. R. 0. McCaldin and K. J. Heidel, "Particulate Emissions from Vehicle
Travel over Unpaved Roads," presented at the 71st Annual Meeting of
the Air Pollution Control Association, Houston, Texas, June 1978.
5. C. Cowherd, et al., Iron and Steel Plant Open Source Fugitive Emission
Evaluation, EPA-600/2-79-103, U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina, May 1979.
6. T. A. Cuscino, Jr., et al. , The Role of Agricultural Practices in
Fugitive Dust Emissions, California Air Resources Board, Sacramento,
California, June 1981.
-------
3.0 EMISSION FACTOR QUALITY RATING SCHEME
In selecting candidate open dust sources emission factors for inclu-
sion in AP-42, the principal consideration centered around the reliability
of each factor being considered in relation to the reliability factors cur-
rently reported in AP-42 for the same source. This section describes the
emission factor quality rating scheme used in this study. It is a refine-
ment of the revised rating model developed by EPA for AP-42 emission fac-
tors, as described in Reference 8. The scheme entails the rating of test
data quality followed by the rating of the emission factor(s) developed
from that test data.
3.1 Rating of Test Data
Test data that were developed from well documented, sound method-
ologies were assigned an A rating. Data generated by a methodology that
was generally sound but either did not meet a minimum test system require-
ment or lacked enough detail for adequate validation received a B rating.
In evaluating whether an upwind-downwind sampling strategy qualified
as a sound methodology, the following minimum test system requirements were
used. At least five particulate measuring devices must be operated during
a test, with one device located upwind and the others located at two down-
wind and three crosswind distances. The requirements of measurements at
crosswind distances is waived for the case of line sources. Also wind di-
rection and speed must be recorded concurrently on-site.
The minimum requirements for a sound exposure profiling program were
the following. A vertical line grid of at least three samplers is suffici-
ent for measurement of emissions from line or moving point sources while a
two-dimensional array of at least five samplers is required for quantifi-
cation of fixed virtual point source emissions. At least one upwind sam-
pler must be operated to measure background concentration, and wind speed
must be measured concurrently on-site.
Neither the upwind-downwind nor the exposure profiling method can be
expected to produce A-rated emissions data when applied to large, poorly
defined area sources, or under very light and variable wind flow conditions.
In these situations, data ratings based on degree of compliance with mini-
mum test system requirements were reduced one letter.
3.2 Rating of Emission Factors
After the test data supporting a particular single-valued emission fac-
tor were evaluated, the criteria presented in Table 2 were used to assign a
quality rating to the resulting emission factor. These criteria were devel-
oped to provide objective definition for: (a) industry representativeness;
and (b) levels of variability within the data set for the source category.
The rating system obviously does not include estimates of statistical con-
fidence, nor does it reflect the expected accuracy of fugitive dust emission
-------
factors relative to conventional stack emission factors. It does however
serve as a useful tool for evaluation of the quality of a given set of emis-
sion factors relative to the entire available fugitive dust emission factor
data base.
TABLE 2. QUALITY RATING SCHEME FOR SINGLE-VALUED EMISSION FACTORS
Code
1
2
3
4
5
6
7
8
9
No. of
test sites
> 3
> 3
2
2
-
-
1
1
1
No. of Total
tests No. of
per site tests
> 3
> 3
> 2 > 5
> 2 > 5
> 3
> 3
2 2
2 2
1 1
Test data
variability
< F2
> F2
< F2
> F2
< F2
> F2
< F2
> F2
-
Adjustment
for EF.
rating
0
-1
-1
-2
-2
-3
-3
-4
-4
Data spread in relation to central value. F2 denotes factor of two.
Difference between emission factor rating and test data rating.
Minimum industry representativeness is defined in terms of number of
test sites and number of tests per site. These criteria were derived from
two principles:
1. Traditionally, three tests of a source represent the minimum re-
quirement for reliable quantification.
2. More than two plant sites are needed to provide minimum industry
representativeness.
The level of variability within an emission factor data set was defined
in terms of the spread of the original emission factor data values about
the mean or median single-valued factor for the source category. The fairly
rigorous criterion that all data points must lie within a factor of two of
-------
the central value was adopted. It is recognized that this criterion is not
insensitive to sample size in that for a sufficiently large test series, at
least one value may be expected to fall outside the factor-of-two limits.
However, this is not considered to be a problem because most of the current
single-valued factors for fugitive dust sources are based on relatively
small sample sizes.
Development of quality ratings for emission factor equations also re-
quired consideration of data representativeness and variability, as in the
case of single-valued emission factors. However, the criteria used to as-
sign ratings (Table 3) were different, reflecting the more sophisticated
model being used to represent the test data. As a general principle, the
quality rating for a given equation should lie between the test data rating
and the rating assigned to the corresponding single-valued factor. The
following criteria were established for an emission factor equation to have
the same rating as the supporting test data:
1. At least three test sites and three tests per site, plus an addi-
tional three tests for each independent parameter in the equa-
tion.
2. Quantitative indication that a significant portion of the emission
factor variation is attributable to the independent parameter(s)
in the equation.
Loss of quality rating in the translation of test data to an emission
factor equation occurs when these criteria are not met. In practice, the
first criterion was far more influential than the second one in rating an
emission factor equation, because development of an equation implies that a
substantial portion of the emission factor variaton is attributable to the
independent parameter(s). As indicated in Table 3, the rating was reduced
by one level below the test data rating if the number of tests did not meet
the first criterion, but was at least three times greater than the number
of independent parameters in the equation. The rating was reduced two le-
vels if this supplementary criterion was not met.
The rationale for the supplementary criterion follows from the fact
that the likelihood of including "spurious" relationships between the depen-
dent variable (emissions) and the independent parameters in the equation
increases as the ratio of number of independent parameters to sample size
increases. For example, a four parameter equation based on five tests
would exhibit perfect explanation (R2=1.0) of the emission factor data, but
the relationships contained in such an equation cannot be expected to hold
true in independent applications.
-------
TABLE 3. QUALITY RATING SCHEME FOR EMISSION FACTOR EQUATIONS
No. of No. of Total No. Adjustment ,
Code test sites tests per site of tests for EF rating
1 > 3 > 3 > (9 + 3P) 0
2 > 2 > 3 > 3P -1
3 > 1 - < 3P -2
P denotes number of correction parameters in emission factor equa-
tion.
Difference between emission factor rating and test data rating.
-------
4.0 CANDIDATE EMISSION FACTORS
The following sections discuss the test reports applicable to AP-42
Section 11.2. For each report, the method of field sampling is described,
including sampling equipment employed and the number and location of test
sites. A quality rating is assigned to the test data based on the rating
scheme described in Section 3. An A rating denotes that the test data were
developed from well documented, sound methodologies. Data generated by a
generally sound methodology which either does not meet the minimum test
system requirements or lacks enough detail for adequate validation receives
a B rating. Also as part of good documentation, the source tested must be
specifically described as to physical operation, mechanical equipment em-
ployed, and material of concern.
After presentation of the emission factor(s) from each test report, an
explanation is given for the emission factor quality ratings assigned ac-
cording to the rating schemes described in Section 3. This is done by in-
dicating the code from Table 2 or Table 3, as appropriate.
Unless otherwise noted, emission factors expressed in units of Ib/T
denote quantity of emissions per quantity of material transferred in a par-
ticular operation.
4.1 Section 11.2.1 - Unpaved Roads
4.1.1 Test Report 1 (1974)
A result of this study was a predictive emission factor equation (see
Table 4) for vehicle traffic on unpaved roads. Field testing took place
at three different sites in southwestern U.S.
The upwind-downwind method was used in this study. Downwind measure-
ments (no upwind sampling performed) were made with a GCA dust monitor (beta
gauge) at two to six distances from the road and at one to three heights.
The downwind distances ranged from 50 ft to 300 ft and the heights ranged
from 3 ft to 10 ft. A high volume samplers were run concurrently for five
of the six tests to determine the ratio of beta gauge to Hi-Vol measurements,
The results showed that the mean Hi-Vol reading was 1.68 times the mean beta
gauge measurement. No particle sizing was performed in this study.
The testing procedure is well documented; however, the sampling system
does not meet the minimum requirements stated in Section 3.1 due to a lack
of upwind sampling and the use of only one or two downwind samplers. There-
fore, the test data are rated C.
A two step process was used to develop the emission factor equation in
this study.
-------
TABLE 4. VEHICLE TRAFFIC ON UNPAVED ROADS EMISSION FACTOR EQUATION,
RANGE OF TEST CONDITIONS, AND RATING (Test Report 1)
Range of conditions
Date and
No. of
tests
8/22-
10/22
6 tests
No.
of test
sites
1
Wind
speed
(mph)
5.4-
10.7
Road
surface
type
70% loams
and sandy
clay, 30%
sandy loams
Vehicle
weight
(tons)
2-3a
Vehicle
speed No. of
(mph) wheels
15-40 4
Rati ng
code Rating
2 D
Actual weights not stated; assume a normal traffic mix weight of 2 to 3 tons.
Emission Factor Equation
E = 0.27 (1.068)X
where: E = total suspended particulate emission factor (Ib/VMT)
X = vehicle speed (mph)
Equation is from page 3-6 of test report.
First, the measured concentrations were substituted into the following line
source equation:
C(*>y>H> = sin* A a u e*P
z
"2 a
z
(1)
where C = concentration
Q = emission rate per unit road length
$ = angle between wind direction and road
a = vertical dispersion coefficient
u = wind speed
H = sampler height
The emission factors thus obtained were then plotted as a function of vehicle
speed. The curve produced was approximated by the emission factor equation
in Table 4, which also gives the range of conditions which were tested. The
rating code refers to Table 3.
4.1.2 Test Report 2 (1976)
This study developed an emission factor equation (see Table 5) to
estimate dust emitted from truck traffic on unpaved roads. Three roads
with two surface types were tested at the central Illinois study site.
10
-------
TABLE 5. VEHICLE TRAFFIC ON UNPAVED ROADS EMISSION FACTOR EQUATION,
RANGE OF TEST CONDITIONS, AND RATING
(Test Report 2)
Range of conditions
Date and
No. of
tests
.
17 tests
No.
of
sites
3
Wind
speed
(mph)
4.4-13.0
Road
silt Road
content surface
(%) type
5-20 Non-
plastic
and clay
Vehicle
weight
(tons)
4.3-8.3
Vehicle
speed
(mph)
10-25
No. of Rating
wheels code
6 2
Rating
B
- = No information contained in test report.
Emission Factor Equation3
E = 5.286 - 3.599(R) + 0.00271(V)(W)(S)
where: E = TSP emission factor (Ib/VMT)
R = road surface type = 1 (nonplastic)
= 0 (clay)
V = vehicle speed (mph)
W = vehicle weight (thousands of pounds)
S = silt (%)
a Equation is from page 1047 of test report.
The upwind-downwind technique incorporating the use of five high-volume sam-
plers (one upwind and four downwind) was employed. Downwind sampling dis-
tances ranged from 50 to 250 ft. Wind speed and direction were measured
using standard meteorological instruments. No particle size analysis was
performed. This system meets the minimum requirements of upwind-downwind
sampling of a line source as described in Section 3.1. This methodology is
well documented and of sound quality; therefore, the test data are rated A.
Emission rates were determined through the use of Equation 1 (Section
4.1.1). These emission rates applied to specific sets of known source pa-
rameters such as vehicle weight, vehicle speed, and road surface silt con-
tent. A stepwise regression analysis was performed with these parameters,
and the predictive emission factor equation resulted.
11
-------
Table 5 presents the testing information, range of conditions, and
rated emission factor equation. The rating code refers to Table 3.
4.1.3 Test Report 4 (1978)
Testing in this study resulted in the development of an emission fac-
tor equation for vehicular traffic on unpaved roads in the Desert Southwest.
Forty-six measurements were made at five different sites.
Upwind-downwind sampling was used in this study. High-volume samplers
(one upwind and one downwind) were used for particulate collection. Verti-
cal plume distribution was estimated by running nine tests with downwind
samplers located at heights of 1, 2, and 3 meters. Measurement of wind
speed involved the use of a hand-held device. No particle size analysis
was performed. This upwind-downwind sampling system does not meet the mini-
mum requirements set forth in Section 3.1 because of an insufficient number
of downwind sampler locations. Therefore, the test results are rated B.
The emission rates were calculated through use of the same dispersion
equation described in Section 4.1.1. These results were plotted against
road surface silt content and the relationship was found to be linear.
Emission rates (calculated at a constant silt content) were then plotted
against vehicle speed. It was found that the emission rate increased with
the square of the speed, as reflected in the predictive emission factor
equation.
Table 6 shows the range of conditions which were tested and the rated
emission factor equation. The rating code refers to Table 3. Although this
equation meets the representativeness criteria, no quantitative estimate of
the significance of the relationships contained in the equation is given.
4.1.4 Test Report 5 (1979)
This report uses the results of four separate testing studies (Test
Reports 3 and 5 and References 8 and 9) to develop the emission factor
equation shown in Table 7. Exposure profiling was used in all of these
tests.
The exposure profiling system consisted of a 6-m vertical mast (4-m
mast for testing of light duty vehicles in Reference 9) supporting four
equally spaced samplers. Each sampler had a directional intake, and the
flow was adjustable to provide for isokinetic sampling. This system meets
the minimum requirements for exposure profiling as set forth in Section 3.1.
Other equipment utilized were: (a) high-volume air samplers for determining
upwind particulate concentrations; (b) dustfall buckets for determining
downwind particulate deposition; and (c) recording wind instruments employed
to determine mean wind speed and direction for adjusting the exposure pro-
filer to isokinetic sampling conditions. Cascade impactors with cyclone
preseparators were used for particle sizing.
12
-------
TABLE 6. VEHICLE TRAFFIC ON UNPAVED ROADS EMISSION FACTOR EQUATION,
RANGE OF TEST CONDITIONS, AND RATING
(Test Report 4)
Range of conditions
Date and
No. of
tests
Summer/77
46 tests
No.
of test
sites
5
Road silt
content
(%)
5-16
Vehicle
weight
(tons)
2-3a
Vehicle
speed No. of
(mph) wheels
10-50 4
Rating
code
2
Rating
C
Test report states normal traffic mix; therefore, the weight range is
assumed to be 2 to 3 tons.
Emission Factor Equation
E = 0.00035 (s)(V)2
where: E = TSP emission factor (Ib/VMT)
s = silt content (%)
V = vehicle speed (mph)
Equation is from page 8 of test report.
The emission rates were determined by special integration (over the
cross section of the plume) of measurements of exposure (mass of particu-
lates collected divided by the area of air sampling intake) and then divid-
ing by the sampling time. The test data were collected using a well-
documented sound methodology and, therefore, are rated A.
Multiple regression analyses were performed on the emission factors and
source parameters from the four studies to develop the predictive emission
factor equation. Table 7 depicts the range of test conditions for which the
equation was developed. Also shown is the emission factor equation which
accounts for particles less the 30 urn in diameter (Stokes). The equation is
rated A based on Rating Code 1 (Table 3).
4.2 Section 11.2.2 - Agricultural Tilling
Test Report 6 (1981)
This study developed an emission factor equation (shown in Table 8)
for agricultural tilling which includes the use of a disc, land plane, or
sweep plow. The sampling procedure (exposure profiling) and emission factor
13
-------
TABLE 7. VEHICLE TRAFFIC ON UNPAVED ROADS EMISSION FACTOR EQUATION, RANGE OF TEST
CONDITIONS, AND RATING
(Test Report 5)
Range of conditions
Date and Wind
No. of No. of speed
tests sites (mph)
a 6 3-19
27 tests
Road silt Road Vehicle Vehicle
content surface weight speed No. of Rating
(%) type (tons) (mph) wheels code Rating
4.3-20 Dirt, crushed 3-157 13-40 4-13 1 A
slag, crushed
rock, crushed
1 imestone
Tests were conducted during four different studies ranging from 1973 to 1979.
b
Emission Factor Equation
E = 5.9 T^
(M
\365)
where: E = suspended particulate (< 30 urn Stokes diameter) emission factor (Ib/VMT)
s = silt content (%)
S = vehicle speed (mph)
w = number of wheels
W = vehicle weight (tons)
d = number of dry days per year (< 0.01 in. rain)
Equation is from page 72, Figure 5-1 of test report.
-------
TABLE 8. AGRICULTURAL TILLING EMISSION FACTOR EQUATION, RANGE OF TEST
CONDITIONS, AND RATING
(Test Report 6)
Range of conditions
Date and Soil silt Soil moisture
No. of No. of content content
tests sites (%) (%)
4/80 6 1.7-88 2.1-15.9
18 tests
Tractor
speed
(mph)
3-5
Implement
type
Disc, land
plane, sweep-
plow
Rating
code Rating
1,2 A, Ba
- = Information not contained in test report.
The A rating applies to the total participate emission factor, whereas a rating of B is
assigned to the IP (< 15 ym aerodynamic diameter) and FP (< 2.5 urn aerodynamic diameter)
(inhalable and fine participate) emission factor equations. See text for explanation.
Emission Factor Equations
Tp
•IP
(s)
(s)
0.6
0.6
EPP 4,53.8 (s)
0.6
-FP
where: ETp = total particulate emission factor
P
ETp = inhalable particulate emission factor (Ib/acra)
rn
= fine particulate emission factor (1b/acrjL)
s = soil silt content
Equation for total particulate is from page 115 and other two equations are from page 117 of
test report.
-------
calculation scheme used in this study were the same as those described in
Section 4.1.4. For the same reasons stated there, the test data are rated A,
The predictive emission factor equation for total particulates was de-
rived through a multiple regression analysis of emission rates, soil silt
content values and soil moisture content values. It was found that the
moisture variable did not improve the predictive capability of the equation
wereas silt content did. The equations for particles smaller than 15 urn
and 2.5 urn aerodynamic diameter were calculated by multiplying the total
particulate equation by the appropriate mass fractions consisting of parti-
cles in the respective size ranges. However, these mass fractions were not
measured in 7 of the 18 tests. For this reason, and for others stated in
the test report, these latter two equations are less precise.
Table 8 gives the range of conditions tested and the emission factor
equations. The equation for total particulate is rated A, but the inhalable
and fine particulate factors are rated B for reasons stated above. The rat-
ing codes refer to Table 3.
4.3 Section 11.2.3 - Aggregate Storage Piles and Materials Handling
4.3.1 Test Report 3 (1978) (batch-drop)
This document developed an emission factor equation (Table 9) for the
batch-drop operation (i.e., front-end loader to truck). Results from two
tests in Reference 9 were also incorporated in the development of this equa-
tion. The testing and emission factor calculation procedures are described
in Section 4.1.4 (profiling), except that the vertical mast was equipped 5~m
crossbeam and a total of six air samplers were operated; for reasons stated
there, the test data are rated A.
The predictive equation was developed by fitting a functional relation-
ship to the test data. The form of the relationship (i.e., the dependence
of emissions on source conditions) was based on the results of other re-
search on fugitive dust sources. Table 9 presents the test conditions under
which the equation was developed. The emission factor rating for this equa-
tion is C because of the small number of tests performed relative to the
number of parameters in the equation. The rating code refers to Table 3.
4.3.2 Test Report 5 (1979) (continuous-drop)
This study resulted in the development of an emission factor equation
(Table 10) for storage pile formation by means of a conveyor stacker (con-
tinuous load-in). The derivation of this equation also incorporated the
results of five tests from Test Report 3. The testing methodology was simi-
lar to that described in Section 4.1.4. The major difference was that the
profiling tower, which included a 3-m crossbeam and a total of six air sam-
plers, was towed at a speed matching the stacker arm, so that the plume
position was fixed relative to the sampling array. The procedure used to
develop the emission factor equation was the same as that described in Sec-
tion 4.3.1 (Test Report 3). The test data are rated A for reasons stated in
that section.
16
-------
TABLE 9. BATCH-DROP EMISSION FACTOR EQUATION, RANGE OF TEST CONDITIONS,
AND RATING
(Test Report 3)
Date and
No. of
tests
4/77
8 tests
Silt
No. of content
sites (%)
2 1.3-7.3
Range of conditions
Moisture Bucket
content Material capacity
(%) type (yd3)
0.25-0.70 Steel slag, 2.75-10
crushed
1 imestone
Wind
speed Rating
(mph) code Rating
1.3-14 2 C
Emission Factor Equation3
F - n nmft
(I) (!l)
(I)2 (I)
where: E = suspended particulate emission (< 30 \jm Stokes diameter) factor
(Ib/ton)
s = material silt content (%)
U = wind speed (mph)
M = material moisture content (%)
Y = bucket capacity (yd3)
a Equation is from page 3-35, Figure 3-7 of test report.
-------
TABLE 10. CONTINUOUS LOAD-IN (PILE FORMATION) EMISSION FACTOR EQUATION, RANGE OF TEST CONDITINS,
AND RATING
(Test Report 5)
Date and
No. of No. of
tests sites
4/77, 6/78 3
7/78
9 tests
Range of conditions
Wind Silt Moisture Drop
speed content content Material height Rating
(mph) (%) (%) type (m) code Rating
1.5-6.0 1.4-19.1 0.64-4.8 Coal, lump 1.5-12.0 2 C
iron ore,
iron ore
pel lets
Emission Factor Equation9
E = 0.0018
(I) (I)
(If
where: E = suspended particulate (< 30 urn Stokes diameter) emission factor
s = material silt content (%)
U = wind speed (mph)
M = material moisture content (%)
H = drop height (ft)
Equation is from page 82, Figure 5-6 of test report.
-------
Table 10 shows the range of conditions under which the testing was con-
ducted and the emission factor equation developed from the results. The
equation is given a rating of C because of the small number of tests per-
formed relative to the number of parameters in the equation. The rating
code refers to Table 3.
4.4 Section 11.2.5 - Paved Roads
Test Report 5 (1979)
This report based the development of a predictive emission factor equa-
tion (Table 11) on results of three separate testing studies (Test Reports 3
and 5, and Quantification of Dust Entrainment from Paved Roadways, U.S. EPA,
July 1977). The three studies were performed by the same investigators.
The testing and emission factor calculations were the same for each and are
described in Section 4.1.4. As stated in that section, the test data are
rated A. The emission factor equation was derived in the same manner as
that described in Section 4.3.1.
Table 11 gives the range of conditions which were tested and emission
factor developed. The equation is given a rating of B (Code 2, Table 3) if
applied to vehicles traveling entirely on paved surfaces (1=1). If I > 1,
the rating of the equation drops to D because of the arbitrariness of the
guidelines for estimating I.
19
-------
TABLE 11. VEHICLE TRAFFIC ON PAVED ROADS EMISSION FACTOR EQUATION, RANGE OF TEST CONDITIONS,
AND RATING
(Test Report 5)
Range of conditions
Date and
No. of No. of
tests sites
9-11/75, 3
6/77,
7/78
16 tests
Wind
speed
(mph)
Light- 17.0
Surface silt Surface
content loading
(%) (Ib/mile)
5.1-92 149-7,060
Vehicle
No. of weight
lanes (tons)
2-4 3-13
Vehicle
speed
(mph)
12b
Industrial
augmentation
1-7
Rating
code Rating
1 B, Db
- = Information not contained in test report.
^ This parameter is defined in the equation below.
Vehicle speed for two out of the 16 tests. Complete data not contained in test report.
c Rating is B for 1=1 and D for I>1.
Emission Factor Equation
where: E = suspendable particulate (< 30 urn Stokes diameter) emission factor (Ib/VMT)
I = industrial road augmentation factor (This parameter takes into account higher emissions
from industrial road as compared to urban roads. I = 7.0 for trucks coming from unpaved
to paved roads and releasing dust from vehicle underbodies. I = 3.5 when 20% of the
vehicles are forced to travel temporarily with one set of wheels on an unpaved road berm
while passing on narrow roads. I = 1.0 for traffic entirely on paved surfaces.
n = number of traffic lanes
s = surface material silt content (%)
L = surface dust loading (Ib/mile)
W = average vehicle weight (tons)
Equation is from page 79, Figure 5-5 of test report.
-------
5.0 EMISSION FACTORS RECOMMENDED FOR AP-42
Presented below are recommendations for updating the AP-42 sections
for which new emission factor data are available as reviewed in Section 4.
5.1 Criteria for Recommendations
Three criteria form the basis for recommending addition of emission
factors to AP-42:
1. Emission factors are available for sources for which no factors
are currently reported in AP-42.
2. For sources that have factors currently reported in AP-42, addi-
tional factors of equal or higher quality rating are available.
3. When more than one emission factor of comparable rating are avail-
able for a given open dust source, they are combined, i.e., either
averaged to form a new single valued emission factor or added to
the data base supporting an updated emission factor equation. If
the ratings of available factors (including those already contained
in AP-42) differ by more than one level, then the factor (or fac-
tors) with the highest quality rating is the one that is recommended,
In recommending emission factors for open dust sources, consideration
must be given to particle size. Equivalent aerodynamic diameter has become
the standard for characterizing the effects of particulate air pollution.
Therefore, aerodynamic particle diameter will be used to characterize the
recommended size specific emission factors.
5.2 Recommendations
This section discusses the emission factors recommended for inclusion
into AP-42. The tables referred to in the text summarize all of the candi-
date emission factors discussed in Section 4. The factors which are flagged
(t) are not recommended for inclusion into AP-42.
Because the emission factors in Test Reports 3 and 5 were presented
by particle size category defined by Stokes diameter, the following proce-
dure was employed to obtain emission factors for particle size categories
defined by aerodynamic diameter:
1. The particle sizing data contained in the test report was
fitted to a log-normal curve. This data usually consisted
of percentages by weight of particulates smaller than a given
particle size expressed in Stokes diameter. These Stokes
diameters were converted to aerodynamic diameters through
multiplication by the square root of the particle density
before fitting the data to a log-normal curve.
21
-------
2. Appropriate data was obtained from the log-normal curve pro-
duced in Step 1 to define the particulate mass fractions con-
sisting of particles smaller than specific size cut-offs,
namely, 30 urn, 15 urn, 10 um> 5 urn, and 2.5 urn aerodynamic
diameter.
3. The results of Step 2 (i.e., percents by weight less than
the specific particle sizes) were divided by the percent by
weight less than 30 |jm Stokes. The ratios determined in
this step could then be multiplied by the given emission
factors to obtain the appropriate factor for each particle
size category.
4. Steps 1 through 3 were repeated for each test for which
particle size data were available. The average of the mass
fractions determined for each particle size category in Step
3 was multiplied by the appropriate emission factor for par-
ticles smaller than 30 pm Stokes diameter given in the test
report.
Tables 12 through 15 present candidate predictive emission factor equa-
tions for the following generic open dust source categories: vehicle traf-
fic on unpaved roads; agricultural tilling; storage piles and materials han-
dling; and vehicle traffic on paved roads. Proportionality constants are
given for various particle size ranges.
An example of how to calculate an emission factor from an equation and
proportionality constant follows. This example involves the use of the
equation for vehicle traffic on unpaved roads in Table 7 as developed in
Test Report 5. To begin with, the correction parameter values for a given
set of source conditions (s = 5%, S = 20 mph, W = 10 tons, w = 6 wheels,
d = 250 days) are substituted into the emission factor equation. Now, the
choice of the proportionality factor (k) to use depends on the particle size
range for which the emission factor is being calculated. For this example,
assume an emission factor for particulates smaller than 30 (jm in aerodynamic
diameter is desired. The k value would then be 0.80. Having made all the
substitutions the equation will be as follows:
E = (0.80X5.9)/ 5\ /20\ /10\°-7/6\°-5/250\
\127 \30/ \ 3/ \4/ 13657
Under the given source conditions, the emission factor for the < 30 urn aero-
dynamic particle size range is 2.6 Ib/vehicle mile traveled.
For vehicular traffic on unpaved roads it is recommended that the size
specific equation from Test Report 5, as given in Table 12, be substituted
for the unpaved road equation currently contained in AP-42. Both equations
were developed by the same organization, and the latter is an update of the
former. As noted in Figure 1, the equation from Test Report 5 has a much
wider applicability than the unpaved road equations developed by other in-
vestigators.
22
-------
ro
CO
TABLE 12. SUMMARY OF VEHICLE TRAFFIC ON UNPAVED ROAD EMISSION FACTOR EQUATIONS
(Test Reports 1, 2, 4, and 5)
(k
r
Emission factor equation
= proportionality constant)3
= k(0.27)(1.068)x
Proportionality constant (k) for particle size
(aerodynamic diameter)
< 30 -•- 15 --10 < 5 < 2.5 Test b
Total TSP (|im) (urn) (pm) (pm) (urn) Units report
1.0 - - - - Ib/VMT 1
Ratine)
01
where: x - vehicle speed (mph)
E = k|5.206 - 3.599(R) + 0.00271(V)(W)(S) |
where: R = road surface type = 1 (nonplastic)
= 0 (clay)
V = vehicle speed (mph)
W = vehicle weight (thousands of pounds)
S = silt (%)
E - k(0.00035)(s)(V)*
where: s = silt content (%)
V = vehicle speed (mph)
where:
s = silt content (%)
S = vehicle speed (mph)
W = vehicle weight (tons)
w = number of wheels
d = number of dry (< 0.01 in. precip. )
clays per year.
1.0
1.0
0.80
0.57
0.45 0.28
Ib/VMT
0.16
Ib/VMT
Ib/VMT
Bt
C|
- = Unable to be determined from information contained in test report.
i = Although value was not presented in test report, it was calculated from repotted particle size information.
I = Not recommended for inclusion into AP-42.
a Use the appropriate value of k to estimate emissions of a cjiven particle size range.
Test Report 5 presented emission factor for size range defined by Stokes diameter. The factor has been adjusted to reflect an
aerodynamic diameter size range using information contained in test report. See Section 5.2 for procedure.
-------
25
MRI (5)
100
200
2 5 10 20
Vehicle Weight, Tons
Figure 1. Ranges of test conditions (applicabilities) of emission factor
equations for vehicle traffic on unpaved roads.
-------
It is recommended that the other equations in Table 12 be excluded
from AP-42. The equation from Test Report 5 is more accurate and has a
wider range of applicability. Although the other equations provide for
direct calculation of TSP emissions, the advantages of the equation from
Test Report 5 more than offset the potential error resulting from the ap-
proximation of TSP as the < 30 pm particle size fraction.
It is recommended that the emission factor equation for agricultural
tilling, as presented in Table 13, be substituted for the equation cur-
rently reported in AP-42. The data base which supported the currently re-
ported factor has been expanded in support of the updated equation.
With regard to emission factors for aggregate storage piles (and mate-
rials handling), dust emissions can be divided into the contributions of
the following distinct source operations that occur within the storage
cycle:
1. Loading of aggregate onto storage piles (batch or continuous drop
operations).
2. Equipment traffic in storage area.
3. Wind erosion of pile surfaces and ground areas between piles.
4. Loadout of aggregate for shipment or for return to the process
stream (batch or continuous drop operations).
It is recommended that the single emission factor equation currently pre-
sented in AP-42 for aggregate storage piles be replaced with separate equa-
tions of higher quality covering each of the source operations listed above.
It is recommended that the equations presented in Table 14 be incor-
porated into AP-42, with the following modifications.
U
1. The factor -F has been added to the numerator of the
batch drop equation.
V
2. The term •? in the same equation has been raised to the
0.33 power.
These modifications were developed by Midwest Research Institute subsequent
to the publication of the cited test reports. The first modification was
made to reflect the dependence of emissions from batch drop operations on
drop height. The second modification was made to remove a physical anomaly
associated with the dumping device capacity term raised to the first power
as originally reported.
For emissions from equipment traffic (trucks, front-end loaders, dozers
etc.) traveling between or on piles, it is recommended that the equations
for vehicle traffic on unpaved surfaces be used. Specifically the equation
25
-------
TABLE 13. AGRICULTURAL TILLING EMISSION FACTOR EQUATION
(Test Report 6)
Emission factor equation
(k = proportionality constant)3
E = k(538)(s)°-6
where: s = silt content (%)
Proportionality constant (k)a for particle size
(aerodynamic diameter)
< 30 < 15 < 10 < 5 < 2.5
Total TSP (pro) (pro) (pm) (vim) (pm) Units Rating
1.0 - 0.33* 0.25 0.21+ 0.15+ 0.10 Ib/acre A-Bb
- = Unable to be determined from information contained in test report.
+ = Although value was not presented in test report, it was calculated from reported particle size information. See Section 5.2 for
procedure. Note that for this test report particle size was given in aerodynamic diameter, therefore, the conversion from Stokes
diameter (a step given in the procedure) was not required.
a Use the appropriate value of k to estimate emissions of a given particle size range.
The A rating applies to the total particulate emission factor, whereas a rating of B is assigned to the < 15 urn and < 2.5 pm
particle size range emission facto'r equations. See text for explanation.
-------
(V)
TABLE 14. SUMMARY OF AGGREGATE STORAGE PILE (AND MATERIALS HANDLING)
EMISSION FACTOR EQUATIONS (Test Reports 3 and 5)
Operation
Batch-drop
Continuous-
drop
Proportionality constant (k)a for particle size
(aerodynamic diameter) range
Emission factor equation < 30 < 15 < 10 < 5 < 2.5 Test b
(k = proportionality constant)3 Total TSP (pm) (pm) (pm) (pm) (pm) Units report Rating
E = k(0.0018)
where: s =
U =
M =
Y =
E = k(0.0018)
where: s -
U =
H =
M =
(1) S)©
/M ii v o 33 - - 0-73 0.48 0.36 0.23 0.13 Ib/T 3 C
© (I)
silt (%)
wind speed (mph)
moisture content (%)
bucket capacity (yd3)
(-) (-) (-)
V5/ ¥ \^° - - 0.77 0.19 0.37 0.21 0.11 Ib/T 5 C
(?)
silt (%)
wind speed (mph)
drop height (ft)
moisture content (%)
- = Unable to be determined from information contained in test report.
a Use the appropriate value of k to estimate emissions of a given particle size range.
Test Reports 3 and 5 presented emission factors for size range defined by Stokes diameter. The factors have been adjusted to reflect
an aerodynamic diameter size range using information contained in test report. See Section 5.2 for procedure.
-------
from Test Report 5, as presented in Table 12, is recommended, for reasons
stated earlier in this section.
For emissions from wind erosion of storage piles, the following TSP
emission factor equation is recommended.
(rs) (235) (E
where EF = total suspended emissions (Ib/day per acre of storage pile
area)
s = silt content of aggregate (%)
d = number of days with < 0.01 in. precipitation per year
f = percentage of time that the (unobstructed) wind speed exceeds
12 mph at the mean pile height
The coefficient in this equation was taken from Reference 9 (which supported
the equation currently in AP-42) based on sampling of emissions from a sand
and gravel storage pile area during periods of inactivity. The factor from
Reference 9 expressed in pounds per acre-day is more reliable than the factor
expressed in pounds per ton of material placed in storage, for reasons stated
in that report. Note that the coefficient has been cut in half to adjust for
the estimate that the wind speed through the emission layer at the test site
was one-half of the value measured above the top of the piles. The other
terms in this equation were added to correct for silt, precipitation and
frequency of high winds as discussed in Test Report 3.
The rating of the wind erosion equation given above is D, because the
correction terms in the equation have not been verified for storage piles
and because the equation is intended, in this case, for application outside
the sand and gravel industry (for which its rating is C). For active coal
piles at western surface coal mines, the emission factor in AP-42 Section
8.24 is recommended.
The emission factor equation for paved roads from Test Report 5, as
presented in Table 15, was developed from testing mainly at industrial fa-
cilities. It is recommended that the equation from Test Report 5 be incor-
porated into AP-42 under a subsection titled industrial paved roads. The
equation retains the quality rating of B if applied to vehicles traveling
entirely on paved surfaces (I = 1.0). If I > 1.0, the rating drops to D
because of the arbitrariness in the guidelines for estimating I. The C-
rated single-valued factor currently contained in AP-42 was based on test-
ing of urban roads, so it should be retained in AP-42 in a separate section
titled urban paved roads.
28
-------
TABLE 15. SUMMARY OF VEHICLE TRAFFIC ON PAVED ROAD EMISSION
FACTOR EQUATIONS (Test Report 5)a
Emission factor equation .
(k = proportionality constant)
Proportionality constant (k) for particle size
(aerodynamic diameter)
< 30 < 15 < 10 < 5 < 2.5
Total
TSP
(Mm)
(pm) (Mm)
(pm) Units Rating
E =
0.7
where: I = industrial augmentation factor
n = number of traffic lanes
s = silt (%)
L = surface loading (Ib/mi)
W = vehicle weight (tons)
0.86
0.64
0.51 0.32
0.17
Ib/VMT
B/D
ro
- = Unable to be determined from information contained in test report.
+ = Although value was not presented in test report, it was calculated from reported particle size information.
I = Not recommended for inclusion into AP-42.
a Test Report 5 presented emission factor for size range defined by Stokes diameter. The factor has been adjusted to reflect an
aerodynamic size range using information contained in test report. See Section 5.2 for procedure.
Use the appropriate value of k to estimate emissions of a certain particle size range.
This parameter is defined in Table 11.
-------
Because generic emission factor equations for open dust sources ex-
plain some of the variance of measured emission factors, the equations are
much more useful for predicting emissions from specific facilities than are
single-valued factors. Even if a single-valued factor accurately represents
the mean of a certain population of sources, its utility decreases when it
is applied to small segments of the population because of the likelihood of
nonrepresentative source characteristics. Therefore, it is recommended that
in the updated industry-specific sections of AP-42, reference be made to the
emission factor equations in Section 11, which allow adjustment of emission
estimates to the specific source population of interest.
5.3 Emission Factor Applicability
5.3.1 Vehicle Traffic on Unpaved Roads
The emission factor equation recommended for vehicle traffic on unpaved
roads retains the assigned quality rating if applied within the ranges of
source conditions that were tested in developing the equation, as follows:
Range of Source Conditions for Unpaved Road Equation
Road
surface
silt Mean vehicle Mean vehicle Mean
content weight speed No. of
(%) Mg tons km/hrmph wheels
4.3-20 2.7-142 3 - 157 21-64 13-40 4 - 13
Also, to retain the quality rating of the recommended equation applied to a
specific unpaved road, it is necessary that reliable correction parameter
values for the specific road in question be determined. The field and
laboratory procedures for determining road surface silt content are given
in Reference 5. In the event that site specific values for correction param-
eters cannot be obtained, the appropriate mean values from Table 16 may be
used, but the quality rating of the equation is reduced to B.
30
-------
TABLE 16. TYPICAL SILT CONTENT VALUES OF SURFACE MATERIALS ON
INDUSTRIAL AND RURAL UNPAVED ROADSd
Industry
Road use or
surface material
No. of test
samples
Silt (%)
Range Mean
Iron and steel
production
Taconite mining and
processing
Western surface coal
mining
Plant road
Haul road
Service road
Access road
Haul road
Scraper road
Haul road
(freshly graded)
14
12
8
2
21
10
5
4.3-13
3.7
2.4
4.9
2.8
7.2
18
9.7
7.1
7.3
5.8
4.3
5.3 5.1
18 8.4
25 17
29 24
Rural roads
Gravel
Dirt
2
1
12 -
13
12
68
References 1, 3, 5, 8, 10, and 11.
The recommendation equation was developed for calculation of annual
average emissions, and thus, is to be multiplied by annual source extent in
vehicle distance traveled (VDT). Annual average values for each of the cor-
rection parameters are to be substituted into the equation. Worst case
emissions, corresponding to dry road conditions, may be calculated by set-
ting p = 0 in the equation (which is equivalent to dropping the last term
from the equation). A separate set of nonclimatic correction parameters and
a higher than normal VDT value may also be justified for the worst case av-
eraging period (usually 24 hr). Similarly, to calculate emissions for a
91-day season of the year using the recommended equation, replace the term
d/365 with the term d/91, and set d equal to the number of dry days in the
91-day period. Also, use appropriate seasonal values for the nonclimatic
correction parameters and for VDT.
5.3.2 Agricultural Tilling
The emission factor equation recommended for agricultural tilling is
rated A if used to estimate total particulate emissions, and B if used for
a specific particle size range. The equation retains its assigned quality
rating if applied within the range of surface soil silt content (1.7 to 88%)
that was tested in developing the equation. Also, to retain the quality
rating of this equation applied to a specific agricultural field, it is nec-
essary to obtain a reliable silt value(s) for that field. The sampling and
analysis procedures for determining agricultural silt content are given in
Reference 6. In the event that a site specific value for silt content cannot
be obtained, the mean value of 18% may be used, but the quality rating of the
equation is reduced by one level.
31
-------
5.3.3 Aggregate Handling
The emission factor equations recommended for batch and continuous drop
operations retain the assigned quality rating if applied within the ranges
of source conditions that were tested in developing the equations, as given
in Table 17. Also, to retain the quality ratings of these equations applied
to a specific facility, it is necessary that reliable correction parameters
be determined for the specific sources of interest. The field and laboratory
procedures for aggregate sampling are given in Reference 5. In the event
that site specific values for correction parameters cannot be obtained, the
appropriate mean values from Table 18 may be used, but in that case, the
quality ratings of the equations are reduced by one level.
TABLE 17. RANGES OF SOURCE CONDITIONS FOR BATCH AND
CONTINUOUS DROP EQUATIONS3
Equation
Silt
content
Moisture
content
Dumping
~
capacity
ycP
Drop height
n ft
Batch drop 1.3 - 7.3 0.25 - 0.70 2.10 - 7.6 2.75 - 10 NA NA
Continuous
drop 1.4-19 0.64 - 4.8 NA NA 1.5 - 12 4.8 - 39
a NA = not applicable.
Worst case emissions from storage pile areas occur under dry windy
conditions. Worst case emissions from materials handling (batch and con-
tinuous drop) operations may be calculated by substituting into the recom-
mended equation appropriate values for aggregate material moisture content
and for anticipated wind speeds during the worst case averaging period, usu-
ally 24 hr. The treatment of dry conditions for vehicle traffic (Section
5.3.1) and for wind erosion, centering around parameter d, follows the
methodology described in Section 5.3.1. Also, a separate set of nonclimatic
correction parameters and source extent values corresponding to higher than
normal storage pile activity may be justified for the worst case averaging
period.
5.3.4 Industrial Paved Roads
The emission factor equation recommended for vehicle traffic on indus-
trial paved roads retains the quality rating of B if applied to vehicles
traveling entirely on paved surfaces (I = 1.0) and if applied within the
range of source conditions that were tested in developing the equation as
follows.
32
-------
TABLE 18. TYPICAL SILT AND MOISTURE CONTENT VALUES OF MATERIALS AT VARIOUS INDUSTRIES
Industry
Si
Material No. of test
samples
It (%) Moisture (%)
No. of test
Range Mean samples Range
Mean
Iron and steel
production
CO
CO
Stone quarrying .
and processing
Pellet ore 10
Lump ore 9
Coal 7
Slag 3
Flue dust 2
Coke breeze 1
Blended ore I
Sinter 1
Limestone 1
Crushed limestone
1.4
2.8
2
3
14
13
19
7.7
7.3
23
1.3 - 1.9
4.9
9.5
5
5.3
18.0
5.4
15.0
0.7
0.4
1.6
8
6
6
3
0
1
1
0
0
0.64 - 3.5
1.6 - 8.1
2.8 - 11
0.25 - 2.2
NA
NA
NA
2.1
5.4
4.8
0.92
NA
6.4
6.6
NA
NA
0.3 - 1.1
0.7
and processing
Western surface
, . - d
coal mining
Pellets
Tailings
Coal
Overburden
Exposed ground
9
2
15
15
3
2.2 - 5.4
NA
3.4 - 16
3.8 - 15
5.1 - 21
3.4
11.0
6.2
7.5
15.0
7
1
7
0
3
0.05 - 2.3
2.8 - 20
NA
0.8 - 6.4
0.96
0.35
6.9
NA
3.4
References 3, 5, 10, and 12.
Reference 3.
Reference 8.
Reference 11.
NA = not applicable.
-------
Silt
content Surface loading No. of Vehicle weight
(%) kg/kmIb/mile lanes Mg tons
5.1 - 92 42.0 - 2,000 149 - 7,100 2-4 2.7-12 3-13
If I > 1.0, the rating of the equation drops to D because of the arbitrari-
ness in the guidelines for estimating I.
Also, to retain the quality ratings of the recommended equation applied
to a specific industrial paved road, it is necessary that reliable correc-
tion parameter values for the specific road in question be determined. The
field and laboratory procedures for determining surface material silt con-
tent and surface dust loading are given in Reference 6. In the event that
site specific values for correction parameters cannot be obtained, the ap-
propriate mean values from Table 19 may be used, but the quality ratings of
the equation are reduced by one level.
TABLE 19. TYPICAL SILT CONTENT AND LOADING VALUES FOR
PAVED ROADS AT IRON AND STEEL PLANTS3
Travel
Industry lanes
Iron and
steel
production 2
Silt (%) Loading
Range
Range Mean kg/km Ib/mi
1.1-13 5.9 18 - 4,800 65 - 17,000
Mean
kg/ km Ib/mi
760 2,700
a References 3 and 10. Based on nine test samples.
REFERENCES*
1. G. Jutze and K. Axetell, Investigation of Fugitive Dust, Volume I -
Sources, Emissions, and Control, EPA-450/3-74-Q36-a, U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina, June 1974.
References 1, 2, 3, 4, 5, 8, 9, 10, 11, and 12 correspond to References
11, 2, 5, 3, 4, 8, 1, 6, 9, and 7, respectively, in AP-42 Section
11.2.1. References 1, 6, and 9 correspond to References 3, 2, and 1,
respectively, in AP-42 Section 11.2.2. References 1, 3, 5, 8, 9, 10,
and 12 correspond to References 8, 2, 3, 6, 1, 4, and 5, respectively,
in AP-42 Section 11.2.3. References 3, 5, and 10 correspond to Refer-
ences 1, 2, and 3, respectively, in AP-42 Section 11.2.6. Tables 14,
16, 17, 18, and 19 are equivalent to AP-42 Tables 11.2.3-2, 11.2.1-1,
11.2.3-3, 11.2.3-1, and 11.2.6-1, respectively.
34
-------
2. R. J. Dyck and J. J. Stukel, "Fugitive Dust Emissions from Trucks on
Unpaved Roads," Environmental Science and Technology, 10(10): 1046-1048,
October 1976.
3. R. Bohn, et al. , Fugitive Emissions from Integrated Iron and Steel
Plants, EPA-600/2-78-050, U.S. Environmental Protection Agency, Re-
search Triangle Park, North Carolina, March 1978.
4. R. 0. McCaldin and K. J. Heidel, "Particulate Emissions from Vehicle
Travel over Unpaved Roads," presented at the 71st Annual Meeting of
the Air Pollution Control Association, Houston, Texas, June 1978.
5. C. Cowherd, Jr. , et al. , Iron and Steel Plant Open Source Fugitive
Emission Evaluation, EPA-600/2-79-103, U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina, May 1979.
6. T. A. Cuscino, Jr., et al. , The Role of Agricultural Practices in
Fugitive Dust Emissions, California Air Resources Board, Sacramento,
California, June 1981.
7. Technical Procedures for Developing AP-42 Emission Factors and Prepar-
ing AP-42 Sections, U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina, April 1980.
8. T. A. Cuscino, Jr., et al. , Taconite Mining Fugitive Emission Study,
Minnesota Pollution Control Agency, Roseville, Minnesota, June 1979.
9. C. Cowherd, Jr., et al., Development of Emission Factors for Fugitive
Dust Sources, EPA-450/3-74-037, U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina, June 1974.
10. R. Bohn, Evaluation of Open Dust Sources in the Vicinity of Buffalo,
New York, U.S. Environmental Protection Agency, New York, New York,
March 1979.
11. K. Axetell, Jr., and C. Cowherd, Jr., Improved Emission Factors for Fugi-
tive Dust From Western Surface Coal Mining Sources, Volumes 1 and 2,
EPA Contract No. 68-03-2924, U.S. Environmental Protection Agency,
Cincinnati, Ohio, July 1981.
12. C. Cowherd, Jr., and T. Cuscino, Jr., Fugitive Emissions Evaluation,
Equitable Environmental Health, Inc., Elmhurst, Illinois, February
1977.
35
------- |