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Initials/Date: LDS_/_3-15-2007 
I£EPA 

United States 

Environmental Protection 

Agency 

• *-•-.-t-_ 

P.2 

Industrial Environmental Research***' .:£PA-6^/£rg& 

Laboratory '^- f c 

Cincinnati OH 4*5268 

Research and Development 

Source Assessment: '°MQ-M-s-i6 

Coal Storage Piles 

b. 
P.3 

EPA-600/2-78-004k 

May 1978 

SOURCE ASSESSMENT: COAL STORAGE PILES 

by 

T. R. Blackwood and R. A. Wachter 

Monsanto Research Corporation 

1515 Nicholas Road 

Dayton, Ohio 45407 

Contract No. 68-02-1874 

Program Element No. 1BB610 

Project Officer 

John F. Martin 

Resource Extraction and Handling Division 

Industrial Environmental Research Laboratory 

Cincinnati, Ohio 45268 

INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY 

OFFICE OF RESEARCH AND DEVELOPMENT 

U.S. ENVIRONMENTAL PROTECTION AGENCY 

CINCINNATI, OHIO 45268 
P.4 

DISCLAIMER 

Thisi, report has been reviewed by the Industrial Environmental 

Research Laboratory-Cincinnati, U.S. Environmental Protection 

Agency, and approved for publication. Approval does not signify 

that! the contents necessarily reflect the views and policies of 

the U.S. Environmental Protection Agency, nor does mention of 

trade names or commercial products constitute endorsement or 

recommendation for use. 

n 
P.5 

FOREWORD 

When energy and material resources are extracted, processed, converted, and used, the related pollutional impacts on our environment and even on our health often require that new and increasingly 

more efficient pollution control methods be used. The Industrial 

Environmental Research Laboratory - Cincinnati (IERL-Ci) assists 

in developing and demonstrating new and improved methodologies that 

will meet these needs both efficiently and economically. 

This report contains an assessment of air emissions from coal 

storage piles. This study was conducted to provide sufficient 

information for EPA to ascertain the need for developing control 

technology for this source. Further information on this subject 

may be obtained from the Extraction Technology Branch, Resource 

Extraction and Handling Division. 

David G. Stephan 

Director 

Industrial Environmental Research Laboratory 

Cincinnati 

m 
P.6 

PREFACE 

The Industrial Environmental Research Laboratory (IERL) of the 

U.S. Environmental Protection Agency (EPA) has the responsibility 

for insuring that pollution control technology is available for 

stationary sources to meet the requirements of the Clean Air Act, 

the: Water Act and solid waste legislation. If control technology 

is unavailable, inadequate, uneconomical or socially unacceptable, 

then financial support is provided for the development of the 

needed control techniques for industrial and extractive process 

industries. Approaches considered include: process modifications, 

feedstock modifications, add-on control devices, and complete process substitution. The scale of the control technology programs 

ranges from bench- to full-scale demonstration plants. 

IERL has the responsibility for developing control technology 

for a large number (>500) of operations in the chemical and related industries. As in any technical program, the first step 

is to identify the unsolved problems. Each of the industries is 

to be examined in detail to determine if there is sufficient 

potential environmental risk to justify the development of control technology by IERL. This report contains the data necessary 

to make that decision for coal storage piles. 

Monsanto Research Corporation (MRC) has contracted with EPA to 

investigate the environmental impact of various industries which 

represent sources of pollution in accordance with EPA's responsibility as outlined above. Dr. Robert C. Binning serves as MRC 

Program Manager in this overall program entitled "Source Assessment," which includes the investigation of sources in each of four 

categories: combustion, organic materials, inorganic materials, 

and open sources. Dr. Dale A. Denny of the Industrial Processes 

Division at Research Triangle Park serves as EPA Project Officer 

for this series. This study of coal storage piles was initiated 

by IERL-Research Triangle Park in May 1974; Mr. David K. Oestreich 

served as EPA Project Leader. The project was transferred to the 

Resources Extraction and Handling Division, IERL-Cincinnati, in 

October 1975; Mr. John F. Martin served as EPA Project Leader 

through completion of the study. 

iv 
P.7 

ABSTRACT 

This;report describes a study of air pollutants emitted from 

coal storage; piles. The potential environmental effect of this 

emission source is evaluated. 

Coal storage piles are open sources of atmospheric emissions of 

fugitive dust and gaseous hydrocarbons. Of the criteria pollutants, carbon monoxide, hydrocarbons, and particle matter are 

emitted. Concentrations of carbon monoxide and hydrocarbons are 

three orders of magnitude below ambient air quality criteria at 

a distance of 50 meters from the pile. The average emission 

factor for respirable particulate (<7 um) is 6.4 mg/kg per year. 

From the distribution of coal piles, a representative pile was 

selected containing 95,000 metric tons of bituminous coal. The 

emission rate from this pile averages 19 mg/s or 610 kg/yr. In 

order to evaluate the potential environmental effect of coal 

storage piles, a source severity factor was defined as the ratio 

of the maximum ground level concentration of an emission to the 

ambient air quality standard for criteria pollutants and to a 

modified threshold limit value for other pollutants. Severity 

factors for a representative coal storage pile are 0.025 and 1.0 

when the emissions are treated as gross particulate and coal dust, 

respectively. 

The national emission burden from all coal storage piles is 

0.00048% of total national particulate emissions. The amount of 

coal stored is increasing at the rate of 3.8% per year and this 

will result in a 25% increase in emissions in 1978 compared to 

1972. 

Air pollution control techniques for coal storage piles have not 

been generally established and no future control techniques are 

presently under consideration. 

This report was submitted in partial fulfillment of Contract No. 

68-02-1874 by Monsanto Research Corporation under the sponsorship 

of the U.S. Environmental Protection Agency. This report covers 

the period May 1974 to September 1975, and the work was completed 

as of July 1977. 
CONTENTS 

P.8 

Foreword 

Preface 

Abstract 

Figures 

Tables 

Abbreviations and Symbols 

Conversion Factors and Metric Prefixes 

1 1 1 

iv 

v 

viii 

ix 

xi 

xiii 

I Introduction 

II Summary 

III Source Description 

A. Process Description 

1. Emission Sources 

2. Source Composition 

B. Factors Affecting Emissions 

C. Geographical Distribution of Coal Storage Piles 

IV Emissions 

A. Selected Pollutants 

B. Mass Emissions 

C. Representative Source 

D. Environmental Effects 

1. Ground Level Concentration 

2. Hazard Factor 

3. Source Severity 

V Control Technology 

A. State of the Art 

B. Future Considerations 

VI Growth and Nature of the Industry 

A. Present and Emerging Technology 

B. Coal Storage Trends 

References 

Appendices 

A. Analysis of Sampling Results 

B. Factors Affecting Coal Storage Emissions 

C. Derivation of Surface Area from Height of 

Coal Piles 

1 

2 

4 

4 

4 

5 

9 

11 

13 

13 

15 

15 

17 

17 

18 

18 

20 

20 

20 

22 

22 

22 

24 

27 

36 

49 

vn 
P.9 

CONTENTS (continued) 

Appendices (continued) 

D. Sampling Equipment and Procedures 51 

E. Computation of Combined Errors 62 

F. Determination of Distance to Plant Boundary and 

Population Density for Representative Coal 

Storage Pile 64 

G. Analysis of Coal Storage Piles for Polycyclic 

Organic Materials 65 

H. Derivation of Source Severity Equations 67 

Glossary 81 

v m 
P.10 

FIGURES 

Number Page 

1 Map of P-E values for state climatic divisions 10 

2 Distribution of coal piles 12 

3 Distribution of quantity of coal stored versus 

P-E region 12 

4 Area affected down to a severity of 0.1 19 

A-l March sampling arrangement, Runs Cl and C2 28 

A-2 August sampling arrangement, Runs CS-3 and CS-5 28 

D-l Fugitive dust sampling worksheet 61 

ix 
P.11 

TABLES 

Number Page 

1 Concentrations of Trace Metals in Coal and Coal Dust 7 

2 Composite TLV of all the Elements in Coal Dust 8 

3 Analysis of Grab Samples for Total Hydrocarbons, 

Methane, Carbon Monoxide and Sulfur (AS H2S, 

S02 and RS) 14 

4 State and National Emissions 16 

5 Comparison of the Representative Coal Storage Pile 

to the Pile Selected for Sampling 17 

6 Source Severity 19 

A-l Sampling Results - March and August 1974 30 

A-2 Data for Calculation of the Constant (k) 33 

A-3 X-ray Fluorescence Analysis of Samples from Filters 34 

A-4 Particle Size Analyses 35 

B-l Sensitivity Analysis of Entrainment/Emission Rates 

Calculated Using Equation B-18 with Average, 

Minimum and Maximum Values for Wind Velocity, 

Bulk Density, P-E Index and Surface Area 47 

C-l Height of Coal Piles 50 

D-l Open Sources Sampling Guidelines 58 

D-2 Placement of Samples Downwind of Obstructions 59 

D-3 Fugitive Dust Sampler and Meteorological Data Log 60 

F-1 Distance to Plant Boundary and Population Density 

for Representative Coal Storage Pile 64 

G-1 Analysis of Coal Samples Extracted with Pentane 

for Selected Polycyclic Organic Materials (POM's) 

by Chemical Ionization Maee Spectroscopy 66 
P.12 

TABLES (continued) 

Number Page 

H-l Pollutant Severity Equations 68 

H-2 Values of a for the Computation of o 70 

H-3 Values of the Constants used to Estimate Vertical 

Dispersion 70 

H-4 Summary of National Ambient Air. Quality Standards 76 

xi 
P.13 

a.', 

mi', 

A, 

AL 

AR/ 

Bl, 

Ci 

• • • , q / 

n 

> • • , G 

BR 

B2 

c, c Cl, 

CSD 

d 

Do 

DS 

E 

ENr 

Ep 

exp 

E 2 , 

F 

F r C 

Fu 

GI, 

• • 

H 

h 

I 

K, ] 

Kir 

L' 

M 

n 

N 

P 

P-E 

C2, 

- 3, CS-5 

ESOr 

'

 E S ' E A 

E3 , E 4 

G2, 

. , G12 

K' 

..., K7 

index 

ABBREVIATIONS AND SYMBOLS 

variable exponents and coefficients used in 

numerous mathematical manipulations 

stability classes; also used to designate 

reference distances for hi-volume samplers 

leading angle at the base of a coal dust bed 

substitution variables 

particle size samples 

concentration of the i-th chemical element 

local wind erosion climatic factor 

valid hi-volume sampler runs 

representative distance 

distance across a field 

annual days of operation of a facility 

storing coal 

average days of supply of coal stored at a 

facility 

potential average annual soil loss 

variables used by different authors to 

represent entrainment rate 

natural log base, e ^ 2.72 

erodibility factor functions 

hazard factor 

total concentration of all i-th chemical 

elements in the dust 

frictional velocity 

gas sample numbers 

height of a coal dust bed 

height of emission 

soil and knoll erodibility index 

surface and ridge roughness 

constants 

unsheltered distance across a field 

along the prevailing wind direction 

moisture content 

number of samples collected 

number of chemical elements 

monthly precipitation 

regional precipitation-evaporation level (as 

expressed by Thornthwaite (Reference 13) 

xn 
P.14 

ABBREVIATIONS AND SYMBOLS (continued) 

ppm 

Q 

2? 

S 

SD 

So r 

T 

t 

T„ 

TLV 

t

M 

.max 

Si*. 

u 

u 

u, 

ave 

V 

V* 

v a 

v, 

w

Vl 

W i 

W t 

X 

X 

x, 

ii 

p b 

a 

u, u ave' 

2__max 

— parts per million 

— emission rate 

— final air flow rate 

— initial air flow rate 

— source severity 

— surface area 

— size distribution 

— hi-volume sampler numbers 

— monthly mean temperature 

« "Student t" value for h - 1 degrees of freedom 

— weight qf coal stored 

— TLV of the i-th chemical element 

— sampling time for which concentrations for 

longer periods are calculated 

— threshold limit value of a material 

— composite TLV of a compound 

— sampling time for which X_= v was determined 

r ,. 3 . . max 

— sampling time 

— arithmetic mean wind speed 

— average wind speed 

— wind velocity at the midheight of a coal 

dust bed 

— volume of a coal dust bed 

— vegetative cover 

— volume of air sampled 

— variables used by different authors for wind 

speed or velocity 

— width of a coal dust bed 

— initial (tare) weight of filter 

— final weight of filter 

— any average value 

— arithmetic mean measure of any value, X 

— downwind coordinate distances 

— a constant approximately equal to 3.14 

— bulk density 

— estimated population standard deviation 

— standard deviation of plume dispersal in 

horizontal plane 

— standard deviation of plume dispersal in 

vertical plane 

— concentration 

— maximum concentration 

— mean ambient concentration 

x m 
P.15 

CONVERSION FACTORS AND METRIC PREFIXES 

To convert from 

degree Celsium (°C) 

kilogram (kg) 

kilogram (kg) 

meter (m) 

meter (m) 

meter (m) 

meter2 (m2) 

meter3 (m3) 

meter3 (m3) 

meter3 (m3) 

meter3 (m3) 

metric ton 

pascal (Pa) 

pascal (Pa) 

radian 

CONVERSION FACTORS 

to 

degree Fahrenheit (°F) 

grain (1/7,000 lb mass 

avoirdupois) 

pound (mass) 

foot 

inch 

yard 

mile2 

foot3 

inch3 

liter 

yard3 

ton 

inch of water (60°F) 

pound-force/inch2 (psi) 

degrees 

Multiply by 

t0 p - 1.8t0(, + 32 

1.543 x IO4 

2.205 

3.281 

3.937 x 101 

1.094 

3.861 x IO"7 

3.531 x 101 

6.101 x IO1* 

1.000 x 10~3 

1.308 

1.102 x 103 

4.019 x 10~3 

1.450 x 10_lf 

5.730 x 101 

METRIC PREFIXES 

Prefix 

kilo 

centi 

milli 

micro 

Symbol 

k 

c 

m 

P 

Multiplication 

factor 

103 

IO"2 

10"

 3 

10"

 6 

Example 

1 kg = 1 x 103 grams 

1 cm = 1 x IO-2 meter 

1 mm = 1 x 10"3 meter 

1 Um = 1 x 10"6 meter 

Metric Practice Guide. ASTM Designation E 380-74, American Society for 

Testing and Materials, Philadelphia, Pennsylvania, November 1974. 34 pp. 

XIV 
P.16 

SECTION I 

INTRODUCTION 

Coal storage piles contribute fugitive emissions to the atmosphere in the form of coal dust. The severity or potential 

environmental risk of emissions from these piles and other open 

sources had been ranked relative to each other through the use of 

an impact factor. This factor is a measure of the local population 

density that is exposed to the maximum concentration of all emissions from coal storage piles relative to the hazardous nature 

of each emission. Although the impact factor was low for coal 

storage piles compared to other open sources, coal storage was 

investigated as a prototype for development of the logic and 

methods to be used in the future assessment of various other 

source types. It also served to test the consistency of the 

logic applied. 

An analysis of coal storage piles was conducted to assess the 

distribution and character of emissions in greater detail than 

is available in the literature. The emphasis of the assessment 

has been to ascertain whether control technology development is 

required. The following data are compiled in this document: 

The number of coal storage piles 

Distribution of coal storage in the U.S. 

A documented emission factor 

The composition of emissions 

The hazard potential of emissions 

The factors which affect the emissions 

Total national emissions 

Contribution to state emissions burden 

A relative severity factor (used in comparing other 

source assessments) 

Type of control technology used and proposed 

Growth of coal storage piles 
P.17 

SECTION II 

SUMMARY 

Coal, storage piles are open sources of atmospheric emissions 

of fugitive dust and gaseous hydrocarbons. The emission rate 

varies due to meteorological and topographical influences. Of the 

criteria pollutants, carbon monoxide, hydrocarbons, and particulate 

matter are emitted. The concentrations of carbon monoxide and 

hydrocarbons are three orders of magnitude below ambient air 

quality criteria at a distance of 50 m (164 ft) from the coal pile. 

Thus, a detailed analysis of the severity was not required. The 

respirable particulate matter (<7 um) emitted is coal dust, which 

has a threshold limit value (TLV®) of 2 mg/m3. These emissions 

were found to be affected by wind speed, surface area of the pile, 

coal density, and regional precipitation evaporation (P-E) index. 

However, a sensitivity analysis indicates that these parameters 

do not preclude the use of an average emission factor of 6.4 mg/kg 

(0.013 lb/ton) per annum. This factor describes the emission rate 

within 6.9 mg/kg (0.014 lb/ton) per annum, 95% of the time. 

From a study of the distribution of coal piles, a representative 

coal pile was defined as containing 95,000 metric tons3 

(100,000 tons) of bituminous coal with an average pile height of 

5.8 tn (19 ft). It is located in a P-E region with an annual index 

of 91 (U.S. average) and an annual average wind speed of 4.5 m/s 

(10 mph). The emission rate from this pile averages 19 mg/s 

(0.15 lb/hr) or 610 kg/yr. The severity of the representative 

pile is 0.025 when the emissions are considered as gross 

particulate, and 1.0 when treated as coal dust. The population 

affected, above a severity of 0.1, is 58 persons. 

The national emission burden from coal storage piles is 630 

metric tons/yr (690 tons/yr) or 0.00048% of total national 

particulate emissions. No state has an emission burden from 

this source of greater than 0.0026% of the state's total 

particulate emissions. 

1 metric ton = 106 grams - 2,205 pounds =1.1 short tons (short 

tons are designated "tons" in this document); conversion factors 

and metric system prefixes are presented in the prefatory pages 

of this report. 
P.18 

In 1973, over 98 x IO6 metric tons (108 x IO6 tons) of coal was 

reportedly stockpiled at over 950 user sites located in 479 counties at coke plants, electric generating stations, and industrial 

boiler facilities. The amount of coal stored is increasing at the 

rate of 3.8% per year, mainly due to the construction of new coalfired plants. This trend will result in an increase in emissions 

of 25% in 1978 compared to 1972. 

Air'pollution control techniques for coal storage have not been 

generally established and no future control techniques are 

presently under consideration. 
P.19 

SECTION III 

SOURCE DESCRIPTION 

A. PROCESS DESCRIPTION 

Emission Sources 

The term coal storage refers to over 98 x 106 metric tons of 

coal stockpiled at coke plants, electric generating stations, 

and industrial boilers (1-4). There are over 950 of these 

facilities reportedly using coal and maintaining coal storage 

piles. Coal mines do not stockpile coal because of safety hazards, 

Bureau of Mines regulations, and the mechanization at today's 

mines. Coal is either conveyed directly from the mine to the 

user, i.e., coke plant, or to the cleaning plant for transport 

to the user. Cleaning plants store coal in bins to facilitate 

transport and handling; little if any storage occurs in the open 

(personal communication with Mr. O'Brien, American Mining 

Congress, Environmental Matters Dept., July 30, 1974). The 

amount of coal stored is a function of the type of facility 

operated. Average coal storage supplies are as follows: 

User 

Coke plants 

Electric utility 

stations 

Industrial 

Average days 

of supply (DB) 

23 

92 

(5) 

(7) 

37 (5) 

Effective 

August 1974 

May 1974 

August 1974 

Annual days of 

operation (Dp) 

365 

365 

205; 

(6) 

(7) 

Estimated value based on authors' industrial experience.. 

(1) Keystone Coal Manual, 1973. McGraw-Hill, Inc., New York, 

New York, 1973. pp. 304-410. 

Electric Utility Statistics. 

February 1974. 

(2) 

(3) 

(4) 

Public Power, 32:28-74, JanuarySteam-Electric Plant Factors/1973 Edition. National Coal 

Association, Economics and Statistics Division, Washingt6n, 

D.C , December 1973. 110 pp. 

Coke Producers in the United States in 1972. Mineral 

Industry Surveys. U.S. Department of the Interior, 
P.20 

The weight of coal stored is calculated from the product of the 

annual consumption of coal per user (1-4) and the ratio of 

average days of supply to annual days of operation (D /D ). 

Fugitive dust is emitted from an open coal storage pile via wind 

and other weathering forces acting on the surface. This process 

is similar tp wind erosion of soil and this document uses many 

of the concepts already developed by other investigators of such 

phenomena to determine emissions from coal piles. Particulates 

are the most generally recognized of the emissions, but gaseous 

materials also emanate from coal storage piles by oxidation of 

the exposed coal and the release of pressure on the solid, due 

to mining and comminution. Some volatile emissions are also 

generated during the weathering process. These gases may cause 

some odor at the pile; however, the chemical species which may 

contribute to this odor are not detectable at hazardous concentrations. Thus odor is not considered in this study. 

2. Source Composition 

There are four major classes of coal: 1) lignite, 2) bituminous, 

3) subbituminous, and 4) anthracite (8). Coal usage breaks down 

as follows (9): 

t». Usage, 

Class 10/3 metric tons 

Bituminous 

Subbituminous 

Lignite 

Anthracite 

330 

200 

10 

6.4 

Since anthracite and lignite account for less than 1.2% and 1.8%, 

respectively of the coal used in the United States (9), only the 

bituminous and subbituminous classes will be considered in this 

report. 

Washington, D.C , November 27, 1973. pp. 2-5. 

(5) Rumblings from the Mines. Time Magazine, 104 (9):35,1974. 

(6) Sheridan, E. T. Coke and Coal Chemicals. In: 1972 Minerals Yearbook, A. E. Schreck, ed. U.S. Department of the 

Interior, Washington, D.C , 1972. pp. 427-460. 

(7) FPC Issues Electric Fuel Consumption Stocks. News Release 

No. 20499, Federal Power Commission, Washington, D.C , 

July 22, 1974. 3 pp. 

(8) A.S.T.M. Standards on Coal and Coke. American Society for 

Testing and Materials, Philadelphia, Pennsylvania, September 

1948. p. 80. 

(9) Minerals Yearbook, 1973, Volume I. U.S. Department of the 

Interior^ Washington, D.C , 1973. pp. 8-36. 
P.21 

Coal seams vary in physical and chemical properties across the 

U.S. However, coal dust is considered hazardous only on a mass 

basis and not by virtue of its composition. A TLV of 2 mg/m3 

applies to all classes of coal (10). Brown, Jacobs and Taylor (11) 

have' studied trace elements in coal and coal dust. Table 1 has 

been developed from their data (10, 11). These results indicate 

that the heavier.elements tend to concentrate in this dust. To 

determine the possible effect of these findings on the hazardous 

nature of the emissions from coal piles, a composite TLV (10) was 

calculated, using Equation 1 below, and compared to that of coal 

dust. The composite TLV of the mixture (Tj/j) was determined in 

order to take into account the effects of trace elements and 

other chemical compounds present in the coal dust. The TLVs of 

the metals and chemical forms that occur most frequently in coal 

dust (Table 2) were used for this analysis. 

Fc 

T = - (1) 

M N C,

 K S TT ' 

where F 

c 

N 

= ]C

 c i = total concentration of all 

i=l elements in the dust 

Ti = TLV of the ith element 

C^ = concentration of the ith element (shown in Table 1) 

N = number of elements, as given in Table 2 

The composite TLV is thus 6 mg/m3, as shown in Table 2, or three 

times that of coal dust. The largest contributor is the quartz 

component (1%). Analysis of dust samples from coal piles 

(Appendix A) shows that quartz is less than 1% and the composite 

TLV could be expected to be higher. Thus, analysis shows that 

coal dust can validly be considered the only hazardous pollutant 

emitted since the composite TLV is higher than the accepted TLV 

for mass coal dust. 

(10) TLVs® Threshold Limit Values for Chemical Substances and 

Physical Agents in the Workroom Environment and Intended 

Changes for 1973. American Conference of Governmental 

Industrial Hygienists, Cincinnati, Ohio, 1973. p. 10. 

(11) Brown, R., M. Y. Jacobs, and H. E. Taylor. A Survey of the 

Most Recent Applications of Spark Source Mass Spectrometry. 

American Laboratory, 4:34-37, November 1972. 

6 
P.22 

TABLE 1. CONCENTRATIONS OF TRACE METALS 

IN COAL AND COAL DUST (11) 

Element 

Weight 

ppm in coal 

Weight 

ppm in coal dust (c.) 

Aluminum 

Arsenic 

Barium 

Bismuth 

Bromine 

Boron 

Cadmium 

Calcium 

Cerium 

Chlorine 

Chromium 

Cobalt 

Copper 

Fluorine 

Gallium 

Germanium 

Iodine 

Iron 

Lanthanum 

Lead 

Magnesium 

Manganese 

Molybdenum. 

Neodymium 

Nickel 

Niobium 

Phosphorus 

Potassium 

Praseodymium 

Rubidium 

Samarium 

Scandium 

Selenium 

Silicon 

Silver 

Sodium 

Strontium 

Sulfur 

Tellurium 

Titanium 

Uranium 

Vanadium 

Yttrium 

Zinc 

Zirconium 

Major 

0.30 

69 

0.20 

0.30 

42 

0.19 

4,000 

13 

130 

4, 

2. 

25 

5. 

8. 

0. 

0. 

1,600 

5. 

3. 

4,500 

30 

3. 

8. 

2.7 

20 

380 

410 

4.7 

3.0 

1.7 

1.3 

0.32 

Major 

0.22 

5,000 

100 

6,100 

0, 

620 

1.9 

12 

7.7 

10 

76 

5 

3 

7 

7 

33 

20 

8 

9 

0 

3 

25 

283,000 

26.4 

453 

7.50 

11.3 

3.80 

3.80 

13,200 

45.3 

230 

170 

11.3 

868 

1.90 

68.0 

18 

3 

79,200 

22 

26 

792 

45 

15 

45 

755 

7 

306 

16,600 

11 

7 

3 

30 

7 

294,000 

7.60 

755 

291 

3,130 

3.80 

15,800 

2.26 

166 

7.60 

415 

60.4 

9 

80 

6 

4 

3 

1 

3 

60 

1 

60 

80 

2 

60 
QJ 

0 0 

•73 H (D 3 K rt H. (D O H a

 3 

3 (D fD Ch Oi P- OJ O rt 3 ro 

ih O H- S» 3 r- 0> O M C 

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B. FACTORS AFFECTING EMISSIONS 

The major parameters that are known to contribute to the emissions 

from coal storage piles are pile geometry, coal erodibility 

(dustiness), wind, humidity, precipitation and temperature. Coal 

erosion has been studied in a wind tunnel and the effects of most 

of these parameters, or their equivalents, evaluated. Soil 

erosion equations have also been used to predict parameter 

influence on coal storage emissions. A complete discussion of. 

these studies is provided in Appendix B. The following paragraphs 

summarize the findings. 

The effects of humidity, precipitation and temperature can be 

combined into one parameter, the Thornthwaite precipitationevaporation (P-E) index. P-E index values are available for all 

parts of the U.S. (12) and are shown in Figure 1. The lower the 

P-E index, the higher the emissions from coal piles. This 

parameter has the greatest effect on emission rate. The P-E 

ratio is calculated as follows: 

10/9 

Monthly P-E ratio = 11.5 1=— " -, n 1 (2) 

12 

P-E index = y (monthly P-E ratios) 

i=l 

where3 P^ = monthly precipitation, in. 

T M = monthly mean temperature, °F , adjusted to a 

constant of 30°F for all values below 30°F 

Coal erodibility is a measure of the dustiness of the coal. It 

has been shown that the bulk density of coal (Pb) is an indicator 

of coal dustiness. Thus, the erosion rate is a function of bulk 

density which has been used as the indicator of windblown emissions. The emission rate is influenced the least by this 

parameter. 

Two remaining parameters that can contribute to emissions from 

coal storage piles are wind speed and pile geometry. A coal pile's 

Nonmetric units are designated for Equation 2 to conform to the 

system of units reported by the author (12) and commonly used. 

(12) Thornthwaite, C. W. The Climates of North America According to a New Classification. The Geoaraphical Review, 

21:633-655, 1931. 
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10 
P.26 

geometry can be related through its surface area. Appendix C 

describes hpw this surface area can be calculated from the total 

weight stored. 

A functional relationship could be derived relating all of these 

parameters to emission rate. This derivation is given in 

Appendix B, but it is not rigorously applied in this document. 

The rationale for this decision is given in Appendix B, which 

shows that the level of emissions from storage piles is adequately 

described through the use of an average emission factor which is 

given in Appendix A. The functional relationship of the emission 

parameters to emission rate is used to show the validity of 

using an emission factor. 

C GEOGRAPHICAL DISTRIBUTION OF COAL STORAGE PILES 

Figure 2 shows the distribution of coal storage piles in the 

U.S. calculated as described in Section III.A.l. P-E index has 

the largest effect on emission rate. A comparison between the 

total weight stored per P-E region and the P-E index shows that 

90% of the coal stored is located in P-E regions with indices 

between 90 and 130 (see Figure 3). This facilitates the use of 

an average emission factor for use in predicting the emission 

rates from the amount stored. 

11 
P.27 

700 

600 

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MEAN = 95,000 metric tons 

MODE=49,000 metric tons 

200 -

100 

L 

200 400 600 800 1,000 1,200 1,400 

SIZE OF COAL PILES, IO3 metric tons 

Figure 2. Distribution of coal piles. 

E 

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13.29) 

(6.161 

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10 20 30 40 50 60 70 90 100 UO 120 130 140 150 160 170 

P-E INDEX 

Figure 3. Distribution of quantity of coal stored 

versus P-E region. 

12 
P.28 

SECTION IV 

EMISSIONS 

A. SELECTED POLLUTANTS 

Wind erosion of coal storage piles results in the emission of coal 

dust. Long-term exposure to coal dust is the principal cause of 

coal mine workers' pneumoconiosis (13). The complicated stage of 

this disease is called progressive massive fibrosis and is characterized by massive destruction of lung tissue resulting in death 

from heart failure, asphyxia, or pneumonia (13). A TLV of 2 mg/m3 

is assigned to coal dust which is also a form of particulate matter 

and one of the five criteria pollutants. Since coal dust is a 

composite of various materials, the hazard potential of the composite can be calculated as the total of all ratios of trace element 

concentrations to the concentration required for a hazard potential equivalent to that of mass coal dust. This was calculated to 

be 6 mg/m3 as shown in Table 2. Since the hazard potential of all 

trace elements is one-third the potential of mass coal dust 

(2 mg/m3), further consideration of hazardous particulate emissions 

beyond coal dust is not necessary. 

Oxidation of coal storage piles results in gaseous emissions such 

as hydrocarbons, ethane, carbon monoxide, and sulfur compounds. 

However, based on the results of sampling emissions at the surface 

and upwind of the pile (see Table 3), it can be seen that in all 

but four cases the upwind concentration of a gas was either nondetectable, or nearly equivalent to the concentration at the 

surface of the pile. This indicates that emissions from the pile 

were quantitatively nonexistent. The maximum concentrations 

reported between upwind and pile samples are not of significance 

either. This can be shown by comparing samples G3 and Gi+ for 

methane and total hydrocarbons, and by comparing samples G5 and 

G6 for carbon monoxide. These pile concentrations are reduced 

(13) Brown, M. C. Pneumoconiosis in Bituminous Coal Miners. 

Mining Congress Journal, 51:44-48, August 1965. 

(14) Turner, D. B. Workbook of Atmospheric Dispersion Estimates. 

Public Health Service Publication No. 999-AP-26, U.S. 

Department of Health, Education, and Welfare, Cincinnati, 

Ohio, May 1970. 84 pp. 

13 
TABLE 3. ANALYSIS OF GRAB SAMPLES FOR TOTAL HYDROCARBONS, METHANE, 

CARBON MONOXIDE AND SULFUR (AS H2 S, S02 AND RS) 

Sample description 

Concentration, ppm by volume3»b 

Total0 

hydrocarbons Methane 

Carbon 

monoxide Sulfur 

Gi - Coal pile #1 

G2 - Upwind of pile #1 

G3 - Coal pile #2 

Gi+ - Upwind of pile #2 

G5 - Coal pile #3 

G6 - Upwind of pile #3 

G7 - Coal pile #4 

(No background 

near power plant) 

Gs - Coal pile #5 (active)e 

G9 - Coal pile #5 (inactive) 

Gi0 ~ Upwind of pile #5 

G11 ~ Coal pile #6 

G12 ~ Upwind of pile #6 

3 . 5 

3 . 2 

60 

3 . 9 

5 . 0 

3 . 0 

8 . 0 

4 . 0 

3 . 0 

5 . 0 

4 . 5 

3 . 0 

1 . 5 

1 . 4 

60 

1 . 6 

1 . 5 

1 . 6 

3 . 0 

3 . 0 

2 . 0 

2 . 0 

3 . 0 

4 . 0 

N.D . 

N.D . 

9 . 0 

N.D . 

19. 0 

1 . 0 

12. 0 

5 . 0 

1 . 0 

1 . 0 

1 . 0 

1 . 0 

N.D. 

N.D. 

N.D. 

N.D. 

N.D. 

N.D. 

5.0 

N.D. 

N.D. 

N.D. 

N.D. 

N.D. 

Sensitivity for total hydrocarbons and methane is ±1 ppm and <1 ppm for 

CO and sulfur compounds. 

Samples of trapped gases, collected in glass flasks through a probe 

inserted in the coal piles. This method is described in Appendix D. 

Expressed as methane equivalent. 

None detected (<1 ppm). 

eActive and inactive refer to the use of the pile'. Inactive piles are 

coated with a tar or oil to prevent oxidation. 
P.30 

by at least three orders of magnitude at a position 50 m from 

the pile (14) (with assumed stability class, C, and mean speed 

of 4.5 m/s). This puts them well below ambient air quality 

standards and these gases do not merit further consideration. 

B. MASS EMISSIONS 

The particulate emission factor for a coal storage pile has been 

shown to be 6.4 mg/kg-yr (Appendix A). The use of this average 

emission factor describes the emissions within 108% at the 95% 

confidence level. The major influencing factor is the P-E index; 

however, 90% of the coal stored is located in P-E regions of 90 

to 130 (see Figure 3) which reduces the effect on emissions to 

±40% from the possible ±8,500% described in Appendix B. This 

emission factor is used in conjunction with the distribution of 

coal storage piles (Figure 2) to give the distribution of emissions. The mean emission rate will thus be 606 kg/yr. State and 

national emissions burdens are given in Table 4. 

For a comparison to other data in the literature, the Woodruff 

and Siddoway equation referenced in Appendix B was used to 

calculate an emission factor for bare, noncrusted, unsheltered 

and isolated fields. This factor is 445 mg/kg-yr in comparison 

to the 6.4 mg/kg-yr of coal storage piles. This is reasonable 

since visual dust clouds from coal piles are rarely observed in 

comparison to barren fields. Only two complaints concerning 

dust due to coal storage have been recorded, one in Illinois and 

another in Minnesota3. In addition, the emissions from barren 

fields contain only about 1% to 2% respirable particles (<7 ym). 

Thus, the respirable emission factor for fields is 6.7 mg/kg-yr. 

This is within 3% of the mass emission factor for coal piles 

which is for respirable particulate. 

C REPRESENTATIVE SOURCE 

The representative coal pile is defined as containing 95,000 

metric tons of bituminous coal piled to an average height of 

5.8 m. It is located in a P-E region of 91 index with an average 

annual wind speed of 4.5 m/s and is 86 m from the nearest plant 

boundary. These are the mean characteristics of all known coal 

piles. The emissions from the representative pile average 

606 kg/yr of coal dust. 

Sampling was conducted at a coal pile containing an average of 

112,000 metric tons of bituminous coal. It was located in a P-E 

region of 103 index with an average annual wind speed of 3.5 m/s. 

The emissions from the sampled coal pile averaged 715 kg/yr. 

During the sampling period, the wind speed averaged 1^.9 m/s and 

These have never been substantiated or quantified as being from 

the coal storage piles. 

15 
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the P-E index was estimated to average 48. It has been shown 

that the factor affecting emissions is the ratio of the cube of 

the wind speed to the square of the P-E index. The sampling conducted is close to representative even though the wind speed and 

P-E index were lower than the average conditions. Table 5 compares the values of the factors affecting the emissions for the 

representative coal storage piles, and the selected pile. There 

is agreement within a factor of two during average conditions and 

sampling conditions between the representative coal pile and the 

pile selected!for sampling. In addition, there is statistical 

agreement between the ayerage and sampling conditions for the 

selected pile! 

TABLE 5. COMPARISON OF THE REPRESENTATIVE COAL STORAGE 

PILE TO THE PILE SELECTED FOR SAMPLING 

Parameter 

Repres 

pile 

average 

sentative 

at U.S. 

conditions 

4.5 

. 91 

9 5 a 20,500 

0.35 

606 ± 648C 

Sample 

Average 

conditions 

3.6 

103 

112 . 

41,400° 

0.18 

715 

pile 

Conditions 

at the time 

of sampling 

1.9 

48 

112 

41,400 

0.12 ± 0.15C 

716 ± 657C 

u, m/s 

P-E index 

Size, 103 metric tons 

s, m2 

u

3 s0*35 

(P-E index)2 

Emission rate, kg/yr 

Area from derivation described in Appendix C. 

Area of coal storage pile from Table A-2 of Appendix A. 

r 

At 95% confidence level. 

D. ENVIRONMENTAL EFFECTS 

Two types of severity are addressed for coal storage piles: 

gross particulate and mass coal dust. All other emissions have 

been shown to be negligible or were not detected in measurable 

quantities. Since the gross particulate emission is 100% coal 

dust, the concentrations downwind are the same and the only 

difference will be the hazard factor. 

1. Ground Level Concentration 

The minimum distance from the representative coal pile to the 

nearest plant boundary has been determined, as described in 

Appendix F, to be 86 m. This is the distance to the point at 

A complete derivation and definition of severity are provided 

in Appendix H. 

17 
which the highest concentration would be observed under class C 

meteorological conditions (approximate U.S. average). The following formula was used to calculate this concentration which 

shall be defined as xm a x (14). 

xmax ~ iro a 

y z 

where* Q = mass emission rate, g/s 

a = 0.209 x0*

9 03 

a = 0.113 x0-

9 11 

z 

u = 4.5 m/s 

This instantaneous ground level concentration at 86 m_is 18 pg/m3. 

This must be corrected to the time-averaged maximum, xmaX' f°r 

24 hours as described by Nonhebel (15) so that the mean concentration becomes 6.4 yg/m3. 

2. Hazard Factor 

The hazard factor, F, is defined as follows for coal dust and is 

used to determine source severity: 

O 1 

F = —— • — — • TLV (4 . 

24 100

 V ; 

The derivation of F utilizes the TLV corrected from 8-hour to 

24-hour exposure with a safety factor of 100 applied to this calculation. The hazard factor for most coal dust is calculated as 

6.7 pg/m3. For gross particulates, F shall be defined as the 

24-hour ambient air quality standard of 260 pg/m3. 

3. Source Severity 

For the representative_coal pile, the maximum severity is determined from the ratio, xmax/F'

 Th e various applicable severities 

are given in Table 6. The area affected down to a severity of 

0.1 is determined using Figure 4 and Table 6 as described below. 

The distance from the coal pile to a coal dust severity of 0.1 is 

determined to be 528 m. To this is added the radius of the pile, 

80 m, since the expression for Q was derived using the edge of 

the pile as a reference. The resulting area of severity involved 

is thus 1.2 x 106 m2. From this is subtracted the area of the 

plant to represent nonpublic exposure to a severity greater than 

0.1. The representative population density is then multiplied 

(15) Nonhebel, G. Recommendations on Heights for New Industrial 

Chimneys. Journal of the Institute of Fuel, 33:479, 1960. 

18 
P.34 

TABLE 6. SOURCE SEVERITY 

Distance, 

m 

86 

528 

Coal dust . 

severity 

1.0 

0.1 

Particulate 

severity 

0.025 

SEVERITY -0.1 -

PLANT BOUNDARY. 

Figure 4. Area affected down to a severity of 0.1. 

by the resulting area to give population exposed. The population 

affected to a severity of 0.1 is 58 persons. The calculation of 

the area affected to a severity of 0.1 is shown below. 

Area of severity involvement = IT (528 m + 80 m) 2 = 1.2 x IO6 m2 

Area of plant = 10 (area of pile) = 200,000 m2 

Area of affected population = 960,000 m2 

Population affected (from Appendix F) = (61 persons/km2) x 

(0.96 km)2 = 58 persons. 

19 
P.35 

SECTION V 

CONTROL TECHNOLOGY 

A. STATE OF THE ART 

Ther^e is no established air pollution control technology for coal 

storage piles. Emissions from coal piles are not commonly recognized as a pollution problem. However, the practices of coating 

somei coal piles with tar derivatives, receiving some coal in a 

moist state from cleaning plants, and storing coal outside where 

it is subjected to precipitation, all unintentionally control the 

entrainment of coal dust. 

Coal is coated with tar derivatives to prevent spontaneous combustion of the pile. Oxidation of volatile components of the coal 

rele'ases heat which, when concentrated, can cause the coal pile to 

spontaneously ignite. Coating of the coal shields it from atmospheric oxidation. In additon, the tar also causes the coal dust 

to adhere to the pile. This increases the resistance of coal dust 

to wind entrainment. Conventional spray (60 parts coal tar:40 parts 

water) is generally effective for 15 days. However, other emulsions 

have been effective for 25 days to 35 days (16) . When coal is 

received at the user site from the cleaning plant, it may still 

contain excess moisture. Moisture retained within the coal functions in a manner similar to the tar coatings described by causing 

the coal dust to adhere to the pile and increase the resistance to 

wind entrainment. Storage of coal outdoors exposes it to rain and 

snow which also creates this condition. 

B. FUTURE CONSIDERATIONS 

There is no control technology under consideration for coal storage 

piles. If a need for control were established through an assessment of the source, initial emphasis would be placed on reduction 

of the primary vehicle of dust entrainment, the wind speed. Wind 

speed has an effect of ±160% on emission rate of dust particles 

with P-E index, bulk density, and surface area values kept constant. 

(16) Fuju, K., T. Adachi, Y. Tsukaoa, K. Okuda, and H. Suzuki. 

Coal Dust Scattering Preventative. Japanese Patent 73 24,983 

(to Nihon Koken Kogyo Co., Ltd.), March 31, 1973. 5 pp. 

20 
P.36 

Reduction of wind speed is possible by construction of barriers 

around a coal pile and storage of coal in a pit or silo. The 

height of such barriers must be greater than the height of the 

pile since the wind will tend to project over the barriers onto 

the pile. Design criteria for barrier construction must also 

enable easy removal and addition of coal to allow this control 

method to be economically feasible. 

Storage of coal in a pit or silo, where possible, appears to be 

the more economical and effective means of wind speed reduction. 

Coal stored within a pit or silo is shielded from wind forces, 

and is less susceptible to spillage in the area around storage 

during loading and unloading. Coal pile spillage is particularly 

prone to emission because the greater surface area exposed to 

the wind permits faster drying of the coal. The spilled coal 

may thus create greater amounts of coal dust than does the coal 

pile. 

The present practices of coating coal with tar derivatives or 

increasing the water content of coal both suppress dust entrainment. However, continued employment of this practice may generate 

additional pollutants. When tar is sprayed onto a coal pile, 

particulates are emitted from the overspray. The solvent content 

LP of the tar applied is also released upon combustion of the tar 

coating on the coal. 

Addition bf water to the coal also suppresses dust entrainment, 

but requires that the coal be dried prior to combustion. Thermal 

drying of coal entails a combustion process which may generate 

additional pollutants. It is also an expensive process and may 

not be economically feasible. 

21 
P.37 

SECTION VI 

GROWTH AND NATURE OF THE INDUSTRY 

A. PRESENT AND EMERGING TECHNOLOGY 

Coal!storage piles are located outdoors to facilitate the loading 

and/or unloading of coal. Outdoor storage also inhibits spontaneous combustion caused by atmospheric oxidation. Wind passing over 

the coal reduces the concentration of heat within the pile. However, coatings are necessary to prevent ignition of the coal in 

areas with high temperatures and low wind speeds. 

It is anticipated that coal will continue to be stored outdoors 

in the future. Coal users are expected to locate new plants near 

mines to reduce transport costs, assure supplies, and avoid the 

stricter environmental standards of more densely populated areas. 

The number of coal piles is increasing as the United States uses 

morel! and more coal as an energy source. Coal consumption is 

anticipated to increase by 7% per year over the next 10 years (17), 

Coal inventories (days of supply) are expected to increase by 3.8% 

per year, which will cause an increase in emission rate of 25% by 

1978 compared to 1972. 

B. COAL STORAGE TRENDS 

Usage of coal in the U.S. has followed a curious pattern. Consumption in 1912 was equivalent to consumption in 1970 (18), when coal 

accounted for 20% of the total energy input of the United States. 

(17) Rieber, M., and R. Halcrow. U.S. Energy and Fuel Demand to 

1985. CAC No. 108R (PB 239 343), National Science Foundation, 

Washington, D.C, May 1974. 44 pp. 

(18) Hottel, H. C , and J. B. Howard. New Energy Technology - Some 

Facts and Assessments. MIT Press, Cambridge, Massachusetts, 

1971. pp. 3-4. 

22 
P.38 

Coal is projected to constitute 30% of energy input, with electric 

utilities predicting an increase of 100% to 275% in the use of 

coal by 1985 (19). 

Utilities will tend to build new facilities near mines, water 

supplies, and on large plots of land. Coal storage piles will 

thus be located in areas of lower population density and will be 

farther from local communities. With more land available, 

future coal piles can be expected to be larger to meet the 

growing energy needs of the country. Coke plants and industrial 

boiler facilities are expected to follow the general trends of 

the utilities because they face similar energy situations and 

j | propose similar solutions. 

(19) Roach, J. W. U.S. Energy Outlook - Fuels for Electricity. 

U.S. Department of "the Interior, Washington, D.C, 1973. 

p. 4. 

23 
P.39 

REFERENCES 

I.,, Keystone Coal Manual, 1973. McGraw-Hill, Inc., New York, 

1-Jew York, 1973. pp. 304-410. 

2. Electric Utility Statistics. Public Power, 32:28-74, 

January-February 1974. 

3. Steam-Electric Plant Factors/1973 Edition. National Coal 

Association, Economics and Statistics Division, Washington, 

D.C, December 1973. 110 pp. 

4. Coke Producers in the United States in 1972. Mineral 

Industry Surveys. U.S. Department of the Interior, 

Washington, D.C, November 27, 1973. pp. 2-5. 

5.; Rumblings from the Mines. Time Magazine, 104(9) :35, 1974. 

6. Sheridan, E. T. Coke and Coal Chemicals. In: 1972 Minerals 

Yearbook, Schreck, A.E. ed. U.S. Department of the Interior, 

Washington, D.C, 1972. pp. 427-460. 

7. FPC Issues Electric Fuel Consumption Stocks. News Release 

No. 20499, Federal Power Commission, Washington, D.C, 

July 22, 1974. 3 pp. 

8. A.S.T.M. Standards on Coal and.Coke. American Society for 

Testing and Materials, Philadelphia, Pennsylvania, September 

1948. p. 80. 

9. Minerals Yearbook, 1973, Volume I. U.S. Department of the 

Interior, Washington, D.C, 1973. pp. 8-36. 

10. TLVs® Threshold Limit Values for Chemical Substances and 

Physical Agents in the Workroom Environment and Intended 

Changes for 1973. American Conference of Governmental 

Industrial Hygienists, Cincinnati, Ohio, 1973. p. 10. 

11. Brown, R., M. Y. Jacobs and H. E. Taylor. A Survey of the 

Most Recent Applications of Spark Source Mass Spectrometry. 

American Laboratory, 4:34-37, November 1972. 

12. Thornthwaite, C W. The Climates of North America According 

to a New Classification. The Geographical Review, 21:633-655, 

1931. 

24 
P.40 

13. Brown, M. C Pneumoconiosis in Bituminous Coal Miners. 

Mining Congress Journal, 51:44-48, August 1965. 

14. Turner, D. B. Workbook of Atmospheric Dispersion Estimates. 

Public Health Service Publication No. 999-AP-26, U.S. Department of Health, Education and Welfare, Cincinnati, Ohio, 

May 1970. 84 pp. 

15. Nonhebel, G. Recommendations on Heights for New Industrial 

Chimneys. Journal of the Institute of Fuel, 33:479, 1960. 

16. Fuju, K., T. Adachi, Y. Tsukaoa, K. Okuda, and H. Suzuki. 

Coal Dust Scattering Preventive. Japan Patent No. 73 24,983 

(to Nihon Koken Kogyo Co., Ltd.), March 31, 1973. 5 pp. 

17. Rieber, M., and R. Halcrow. U.S. Energy and Fuel Demand to 

1985. CAC No. 108R (PB 239 343), National Science Foundation, 

Washington, D.C, May 1974. 44 pp. 

18. Hottel, H. C , and J. B. Howard. New Energy Technology -

Some Facts and Assessments. MIT Press, Cambridge, 

Massachusetts, 1971. pp. 3-4. 

19. Roach, J. W. U.S. Energy Outlook - Fuels for Electricity. 

U.S. Department of the Interior, Washington, D.C, 1973. 

p.4 . 

20. Singer, J. M., F. B. Cook, and J. Gurmer. Dispersal of Coke 

and Rock Dust Deposits. Bureau of Mines RI-7642, U.S. Department of the Interior, Pittsburgh, Pennsylvania, 1972. 32 pp. 

21. Dawes, J. G. Dispersion of Dust Deposits by Blasts of Air -

Part 1. Research Report No. 36, Ministry of Fuel and Power, 

Safety in Mines Research Establishment, Sheffield, England, 

May 1952. 69 pp. 

22. Woodruff, N. P., and F. H. Siddoway. A Wind Erosion Equation. 

Soil Science Proceedings, 29:602-608, May 1952. 

23. Bagnold, R. A. The Physics of Blown Sand and Desert Dunes. 

Metheun and Co., London, England, 1954. 265 pp. 

24. Shafer, H. J. A model Study of the Reduction of Wind Transport of Fine Particles by Aerodynamic Barriers. Presented 

at the Fifth Annual Conference on Aviation and Astronautics, 

Tel Aviv and Haifa, Israel, 1963. pp. 57-63. 

25. Woodruff, N. P., and W. S. Chepil. Sedimentary Characteristics of Dust Storms II - Visibility and Dust Concentration. 

American Journal of Science, 2:104-114, February 1957. 

25 
P.41 

26. Cowherd, C , K. Axetell, Jr., and G. Jutze. 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. 172 pp. 

27. Jutze, Go A., K. Axetell, and W. Parker. Investigation of 

Fugitive Dust - Sources, Emissions, and Controls. EPA 

Contract 68-02-0044, Task Order 9, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, 

May 1973. 61 pp. 

28. Annual Report of Research and Technologic Work on Coal. 

Bureau of Mines IC-7518, U.S. Department of the Interior, 

Washington, D.C, 1949. p. 39. 

29. "Federal Register, 36(228), November 25, 1971. 

30. Martin, D. O., and J. A. Tikvart. A General Atmospheric 

Diffusion Model for Estimating the Effects on Air Quality of 

One or More Sources. Presented at the 61st Annual Meeting 

of the Air Pollution Control Association, St. Paul, Minnesota, 

June 23-27, 1968. 18 pp. 

31. Tadmor, J., and Y. Gur. Analytical Expressions for the 

Vertical and Lateral Dispersion Coefficients in Atmospheric 

Diffusion. Atmospheric Environment, 3(6):688-689 , 1969. 

32. Gifford, F. A., Jr. An Outline of Theories of Diffusion in 

the Lower Layers of the Atmosphere. In: Meteorology and 

Atomic Energy 1968, Chapter 3, D. A. Slade, ed. Publication 

No. TID-24190, U.S. Atomic Energy Commission Technical Information Center, Oak Ridge, Tennessee, July 1968. p. 113. 

33. Code of Federal Regulations, Title 42 - Public Health, 

Chapter IV - Environmental Protection Agency, Part 410 -

National Primary and Secondary Ambient Air Quality Standards, 

April 28, 1971. 16 pp. 

26 
P.42 

APPENDIX A 

ANALYSIS OF SAMPLING RESULTS 

1. MASS EMISSIONS RATES 

Four sampling runs were performed during two different periods, 

March and August 1974, at a coal pile site. Sampling equipment 

and procedures are described in Appendix D. Since the variability of emissions from a single coal pile is greater than the 

variations between coal piles (see Appendix B.3.c. for basis) 

the results were considered as four separate samples at one coal 

pile. The positions of the samplers during March and August are 

shown respectively in Figures A-l and A-2. Except for one day, 

coal was not being transferred or moved at the pile by bulldozers 

during the sampling. This activity would be expected to generate 

additional dust that was not due to the storage of coal. In 

fact, there was no statistical difference noted. In addition, 

the pile selected for sampling was located in a rural, nonindustrialized area in order to avoid any possible interference 

from particulates generated at other sources. 

The sampler labeled S0 was positioned upwind of the pile for use 

as a reference to the particulate concentration in the atmosphere, 

prior to the addition of particulates from the coal pile. Subtraction of the concentration level at S0 from the concentrations 

obtained at downwind samples Si through S_, yielded the concentration levels due to the emissions from the coal pile. Turner's 

atmospheric dispersion equation (14) was then used to calculate 

the mass emission rate, Q, from the coal pile: 

Q = Xyaziru (A-l) 

where x = concentration with no effective plume rise 

TT = 3.14 

o o = horizontal and vertical dispersion as a 

v function of downwind distance and atmospheric stability 

u = mean wind speed 

27 
WIND DIRECTION 

to 

oo 

CRUSHER 

HOUSE 

S0 

S • HIGH-VOLUME SAMPLER LOCATION 

WIND DIRECTION 

I 

s0 

CRUSHER 

E HOUSE 

5' 

j—: S4 

S • MGI+VOLUME SAMPLER LOCATION 

Figure A-l. March sampling arrangement, 

runs Cl and C2. 

Figure A-2. August sampling arrangement, 

runs CS-3 and CS-5. 
P.44 

a. Mean Emission Factors 

The mean emission factor for all the emission rates calculated at 

each of the sampler positions is 6.4 mg/kg-yr with a sample standard deviation of 2.54 (Table A-l). However, the errors associated 

with sampling and the use of Equation A-l are combined as shown in 

Appendix E to yield an overall standard deviation of 4.3. Since 

confidence limits are calculated as follows, 

C L . ' (@ 95% level) = ^ - (A-2) 

•n 

where a = estimated population deviation 

t = "Student t" value for n-1 degrees of freedom 

@ 95% level 

n = number of samples 

and o = 4.3 

n = 4 

t = 3.182 

the 95% confidence limits are 6.9 using the emission factor of 

6.4 mg/kg-yr. 

b. Correlation With Factors Affecting Emissions 

Emission rate is calculated from Equation B-18, Appendix B (shown 

here for reader convenience): 

. a b c ku p, s 

Q = d~ (A-3) 

(P-E)a 

where Q = emission rate, mg/s 

k = constant 

u = wind speed, m/s 

P^ = bulk density, g/cm3 

s = surface area 

P-E = Thornthwaite1s precipitation-evaporation 

index (or P-E index) 

In order to apply this equation in determining the extent of 

emissions from all 950 coal piles, the most probable exponents 

were chosen from similar wind erosion studies performed on coal 

piles. In Appendix B, the following exponents for the parameters 

of Equation A-3 were presented: 

2.7 <_ a ± 3.0 (wind speed) 

2.0 < b < 5.9 (bulk density) 

c = 0.345 (surface area) 

d = 2.0 (P-E index) 

29 
P.45 

TABLE A-l . SAMPLING RESULTS - MARCH AND AUGUST 197 4 

Run number 

Date 

Parameter 

Wind speed, m/s 

Wind direction^ radians 

(°) 

Wind direction range, 

radians 

(°) 

Atmospheric stability class 

a Distance, m A 

B 

c 

D 

E 

" " (estimated) F 

" " (estimated) G 

Wet bulb temperature, °C 

Dry bulb temperature "C 

Barometric pressure, kPa 

(mm Hg) 

Concentration at SQ, ug/m3 

S j " 

S2 

S3 

Si* 

Dust <10 ym,C % 

Moisture in source, % 

Emission rate, mg/s 

Sample standard deviation, mg/s 

Coal stored, 103 metric tons 

Emission factor, mg/kg-yr 

Cl 

3/28/74 

2.7 

+1.08 

(+61.6) 

0.701 

(40.2) 

B 

13.4 

37.5 

23.8 

13.4 

34.4 

73.2 

396 

11.9 

15.3 

99.2 

(744) 

75 

107 

127 

112 

106 

100 

10 

22.4 

15.1 

89.4 

7.91 

C2 

3/27/74 

CS-3 

8/20/74 

Value 

1.7 

+0.633 

(+36.3) 

0.914 

(52.4) 

B 

28.2 

44.8 

24.7 

26.5 

• 45.1 

91.4 

122 

7.80 

11.7 

101 

(754) 

55 

60 

84 

71 

55 

100 

11 

12.9 

7.10 

89.4 

4.55 

1.5 

-0.680 

(-39) 

0.489 

(28) 

B 

12.8 

41.1 

15.8 

7.6 

13.7 

122 K 

(none) 

22.2 

29.4 

100 

(752) 

58 

63 

83 

140 

89 

100 

2.3 

14.2 

11.4 

134 

3.34 

CS-5 

8/22/74 

1.5 

+0.140 

(+8) 

1.03 

(58.9) 

B 

4.3 

30.5 

54.9 

3.0 

42.7 

152 

(none) 

22.2 

29.4 

100 

(751) 

138 

341 

420 

391 

262 

100 

2.2 

41.3 

13.2 

134 

9.72 

See Figures A-l and A-2. 

Elevated 4.6 m. 

"See Appendix A.3. on particl e siz e distribution . 

Average emission factor 

Sample standard deviation 

Estimated population standard deviation 

6.38 mg/kg-yr 

2.54 mg/kg-yr 

2.94 mg/kg-yr 

30 
P.46 

For wind speed, seven different studies were cited (Appendix B) 

relating the effect of wind speed to emission rate. Each of these 

studies was conducted over specified ranges of wind speed. Coal 

storage piles are subjected to mean wind speeds in the range of 

1.3 to 6.7 m/s. For this range the effect on emission rate can be 

closely approximated by Q a u3. Therefore, u3 can be established 

as the relationship representing the effect of wind speed. Two 

studies were cited (Appendix B) that relate the effect of bulk 

density to emission rate. The first study, by Singer, Cook, and 

Grumer (20), determined the effect on bulk density to be represented by Q a pb5-9- However, this study was performed on "freeflowing" deposits of coal particles. These deposits were composed 

of particles between 100.pm and 150 ym in size. In the assessment 

of coal storage, from a hazard potential standpoint, only those 

particles within the respirable range (less than 7 pm) are of 

interest. Therefore, the effect of bulk density represented by 

Pb5*

9 is discarded. The second study was performed by Dawes (21) 

who related bulk density to emission rate as Q a Pb2« In this 

study no specific mention of the particle size range under analysis 

was cited; however, particles were classified as fine coal dust, 

which is the class of particles expected from coal storage emissions. Therefore, the effect of bulk density on emission rate in 

this study is represented by pb2. 

Only one relationship was established for surface area, and this 

was obtained via regression analysis of the Singer, Cook, and 

Grumer study. Surface area was found to be related to emission 

rate by Q a s° '

3k5

. 

The remaining parameter, Thornthwaite's precipitation-evaporation 

index, has also been analyzed by various investigators. All 

studies indicated that surface moisture, as represented by the 

P-E index (which has values for each climatic region), was approximated by Q a (P-E)-2. Therefore, Equation A-3, through the use 

of these most probable exponents, becomes: 

ku3pb

2s°-3lt5 

Q = —;—r;— (A_4) 

(P-E)2 

where k is a constant. 

(20) Singer, J. M., F. B. Cook, and J. Gurmer. Dispersal of Coke 

and Rock Dust Deposits. Bureau of Mines RI-7642, U.S. Department of the Interior, Pittsburgh, Pennsylvania, 1972. 

32 pp. 

(21) Dawes, J. G. Dispersion of Dust Deposits by Blasts of AirPart 1. Research Report No. 36, Ministry of Fuel and Power, 

Safety in Mines Research Establishment, Sheffield, England, 

May 1952. 69 pp. 

31 
P.47 

To obtain the value of the constant without further sampling, the 

sampling results in Table A-l were fitted to Equation A-4. The 

data (from Table A-l) used in calculating k from Equation A-4 are 

listed in Table A-2. The resulting arithmetic mean value of the 

constant k from the four runs is 336 with an estimated standard 

deviation of 200. Equation A-4 then becomes: 

u 3 p 2s0.3<+5 

Q = (336) B .(A-5) 

(P-E)2 

where Q is in mg/s, 

The error associated with the use of Equation A-5 must be corrected 

for the error in determining Q as shown in Appendix E. Therefore, 

the estimated population standard deviation becomes 261 and the 

95% confidence limits are ±416.a 

2. COMPOSITION 

Filters were analyzed for major elements by x-ray fluorescence as 

described in Appendix D. Results of this analysis are given in 

Table A-3. In addition, an infrared analysis was performed for 

free silica and it was concluded that less than 1% is present in 

the dust samples. 

3. PARTICLE SIZE ANALYSIS 

The filters were subjected to microscopic evaluation as described 

in Appendix D. The results, reported in Table A-4, indicated 

few particles greater than 10 ym in size. Because of the low 

emission rate only one Brink® sample was obtained. Eighty-eight 

percent of the particles from a composite sample taken over the 

2 sample days in August were less than 5 ym in size. Based upon 

this evidence, it is concluded that essentially all of the 

emissions are in the respirable range. 

This assumes that there are four samples taken. In reality 

the number lies between two and four for each parameter 

evaluated. Four was chosen to represent the best case for 

this error. 

32 
TABLE A-2. DATA FOR CALCULATION OF THE CONSTANT (k) 

Run number 

Date 

Parameter 

Cl 

3/28/74 

C2 CS3 

3/27/74 8/20/74 

Value 

CS5 

8/22/74 

Ul 

UJ 

Wind speed (u), m/s 

Bulk density (p, ), g/cm3 

Quantity stored (W ) , 103 metric 89.4 

Avg. pile height (h), m 

Surface area (s), m2 

Weeks precipitation, mm 

Avg. temperature, °C 

P-E index (estimate) 

Emission rate (Q), mg/s 

k 

2.7 

0.8 

Lc 89.4 

3.6 

46,500 

17.5 

15.3 

60.5 

22.4 

159.7 

1.7 

0.8 

89.4 

3.6 

46,500 

17.5 

11.7 

70.7 

12.9 

503.1 

1.5 

0.8 

134 

4.6 

36,400 

14.5 

29.4 

30.8 

14.2 

166.5 

1.5 

0.8 

134 

4.6 

36,400 

14.5 

28.3 

31.8 

41.3 

516.1 

Arithmetic mean value of k: 336 

Standard deviation (estimate):' 200 
P.49 

TABLE 

Element 

Sodium 

Magnesium 

Aluminum 

Silicon 

Sulfur 

Chlorine 

Potassium 

Copper 

Titanium 

Chromium 

Manganese 

Iron 

A-3. X-RAY FLUORESCENCE ANALYSIS 

OF SAMPLES FROM FILTERS 

Filter 

g/m2 

0.01 

<0.01 

a 

b 

0.04 

<0.01 

<0.01 

<0.02 

a 

a 

a 

0.03 

#2 Filter #9 

g/m2 

0.05 

<0.01 

a 

b 

0.05 

<0.01 

<0.01 

<0.02 

N.D.d 

N.D. 

N.D. 

<0.01 

Filter #11 

g/m2 

' 0.01 

<0.01 

a 

b 

0.13C 

<0.01 

<0.01 

<0.02 

a 

a 

a 

0.02 

a 

Denotes presence possible, but just above background, 

probably less than 0.001 g/m2. 

Denotes presence likely, but unable to provide an estimate 

due to interference of tungsten in line (from x-ray tube) 

as well as high counts in this region from the Nucleopore® 

filter blank. 

No other metal seems to be associated with the increase 

in sulfur content. This may suggest presence of organic 

sulfur, sulfuric acid, etc. 

<0.0006 g/m2. 

34 
TABLE A-4. PARTICLE SIZE ANALYSES 

Sample Bl Sample B2 

Number of Number of 

Size range, ym particles Wt. % Size range, ym particles Wt. % 

UJ 

Ul 

0 

1.2 

2.4 

4.8 

9.6 

19.2 

38.4 

to 

to 

to 

to 

to 

to 

to 

1.2 

2.4 

4.8 

9.6 

19.2 

38.4 

76.8 

Fibers 

102 

123 

34 

16 

5 

3 

0 

: 0 

0.10 

0.76 

1.67 

6.29 

15.72 

75.46 

0 

0 to 

1.2 to 

2.4 to 

4.8 to 

9.6 to 

19.2 to 

1.2 

2.4 

4.8 

9.6 

19.2 

38.4 

Fibers 

93 

106 

31 

14 

4 

0 

: 0 

0.48 

3.20 

7.48 

27.04 

61.80 

0 

These conversions of particle number to weight percent are estimates 

only and assume spherical particles of uniform density. 
P.51 

APPENDIX B 

FACTORS AFFECTING COAL STORAGE EMISSIONS 

1. INFORMATION 

In this source assessment a study was made to determine the 

factors that affect emissions and/or entrainment rates for ojpen 

coal storage piles. Unfortunately, no data directly applicable 

to this pollutant source were available. However, data from', investigations of somewhat similar problems were readily available. 

The bulk of the empirical relationships expressed in this study 

were derived from the results of wind tunnel experimentation 

conducted by the Pittsburgh Mining and Safety Research Center, 

Pittsburgh, Pennsylvania (20). This study was performed to 

determine minimum air velocities and entrainment rates for coal 

bed and rock dust dispersion under conditions that simulate dispersion from surfaces in coal mines where airflows are induced by 

weak explosions. The investigation analyzed the effect of a 

number of factors also believed to influence wind erosion of open 

coal storage piles. These variables are: 

Wind velocity at the midheight of the coal dust 

bed, uL, m/s 

Bulk density of the coal dust bed, pb, g/cm3 

Surface area of the coal dust bed, s, cm2 

Leading angle at the base of the coal dust bed, 

Aj^, degree (free-flowing deposits only) 

Volume of the coal dust bed, V, cm3 

Height of the coal dust bed, H, cm 

Width of the coal dust bed, W, cm (cohesive 

deposits only) 

Data presented were of a rather limited nature, encompassing an 

extremely narrow range of values for each variable. Dust bed 

geometry data were particularly limited in all dimensional 

aspects. Dust bed composition was limited to two principal 

classifications: 

36 
P.52 

• Free-flowing coal dust beds, limited to 

particles 100 ym to 150 ym in diameter 

• Cohesive coal dust beds, containing 

particles 6 ym to 80 ym in diameter 

The two types of dust beds differed not only in particle size 

distribution, but. also in their respective modes of dispersion. 

At the. high wind velocities (considered 10 to 60 mph), freeflowing deposits were entrained by single particle detachment 

while cohesive deposits dispersed by clump removal. 

Since open coal storage piles are rarely subjected to wind speeds 

capable of initiating dispersion by clump removal, empirical relationships derived from experimentation on free-flowing deposits 

are considered more applicable to open coal storage. 

2. DERIVATION OF PARAMETERS 

a. Wind Velocity, u_ , u _.r . (m/s) 

Li ave 

Relationships between entrainment and wind velocity have already 

been derived (21): 

E oc u2*

1 or E « u 2-7 (B-l) 

n L n ave 

Where E = entrainment rate, g/s of free-flowing 

dust beds 

uT = air velocity in the wind tunnel at the 

midheight of the dust bed, m/s 

u = mean air velocity in the wind tunnel, m/s 

d V6 

37 
P.53 

Other investigators have derived similar relationships: 

Entrainment 

rate 

Eso 

ESA 

ESA 

En 

E 

P 

E s 

E A 

oc 

oc 

cc 

oc 

oc 

oc 

GC 

V

3 

Fu,3 

U

 2 -7 

ave 

u

 3 

ave 

v

 9 

VF 

v

9 

v

3 

Wind speed range, 

m/s . 

1.3 to 6.7 

>4.5 

4.5 to 8.9 

>6.7 

0 to 0.9 

<1.3 

1.3 to 8.9 

Reference 

22 

23 

20 

21 

24 

25 

26 

where all E terms are symbols for entrainment rate and wind 

velocity is expressed as Fu, u, or v. 

b. Bulk density, p., (g/cm3) 

Relationships between entrainment rate and bulk density have 

already been derived (20). 

E <* p,5 ,9 (100 ym to 150 ym particle diameter) ' (B-2) 

(22) Woodruff, N. P., and F. H. Siddoway. A Wind Erosion Equation, 

Soil Science Proceedings, 29:602-608, May 1952. 

(23) Bagnold, R. A. The Physics of Blown Sand and Desert Dunes. 

Metheun and Co., London, England, 1954. 265 pp. 

(24) Shafer, H. J. A Model Study of the Reduction of Wind 

Transport of -Fine Particles by Aerodynamic Barriers. 

Presented at the Fifth Annual Conference on Aviation and 

Astronautics, Tel Aviv and Haifa, Israel, 1963. pp. 57-63. 

(25) Woodruff, N. P., and W. S. Chepil. Sedimentary 

Characteristics of Dust Storms II - Visibility and Dust 

Concentration. American Journal of Science, 2:104-114, 

February 1957. 

(26) Cowherd, C., K. Axetell, Jr., and G. Jutze. 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. 172 pp. 

38 
P.54 

Bulk density is an extremely important entrainment factor for 

free-flowing deposits because, at some critical wind velocity, 

dispersion may change from single particle to clump detachment. 

Dawes (21) reports an additional relationship for the effect of 

density on fine coal dust: 

E_ °= p,

 2 (particle size range unknown) (B-3) 

The relationship is dependent upon particle size and thus bulk 

density will reflect fineness of the coal dust. 

c. Surface Area, s, (cm2) 

Due to a wide scattering of data, the investigators (20) derived 

no relationship between entrainment rate and dust bed surface area 

for free-flowing deposits. However, by employing a regression 

analysis on their data, the following approximate relationship was 

determined for free-flowing dust beds: 

E cc s0.3*+5 (B-4) 

n 

d. Other Wind Tunnel Study Parameters 

The parameters listed below were studied in a wind tunnel and no 

relationship was found (20) . A regression analysis shows that 

their effect on emissions, if any, is not as pronounced as those 

of the other parameters. The height, volume, and possibly the 

leading angle may be expressed as functions of surface area: 

Function Relationship 

Angle, deg. E «• AT°-11+9 

n ii 

Volume, cm E <•<- v0,2 5 

n 

Height, cm E « H 0 -

2 2 8 

r n 

Width, cm E a w0 -

3 8 6 

n 

e. Nonwind Tunnel Study Parameters 

A number of factors thought to influence open coal storage emissions were not considered in the aforementioned investigation. 

These factors include: 

• Length of the coal pile along the prevailing 

wind direction (22) 

39 
P.55 

• Particle-size distribution (22) (effects independent of bulk density)a 

Surface moisture (12, 22, 26, 27) 

They were assessed in other studies, although the relationships 

derived were based on wind erosion of soil and windblown emissions 

from tailings and aggregate storage piles. The quantitative aspects of these factors relative to entrainment rates are discussed 

below. • 

(1): Length— 

Ec n « f (L' - b) n (Reference 22) (B-5) 

where L' = length of exposed field areas 

This relationship may not be applicable to open coal storage due 

to the relatively small values for L1 involved and the geometric 

differences between fields and storage piles. This function 

attempts to relate "avalanching" which generally is not precipitated in less than several hundred yards. Coal piles are usually 

not long enough for this to occur. 

(2) Particle Size Distribution— 

E a i (Reference 22) (B-6) 

where I = the soil erodibility index for different soil fractions 

This relationship may not be applicable to open coal storage in 

its present form due to physical and chemical dissimilarities between coal particles and soil fractions. Since this assessment 

is primarily concerned with respirable dust (<7 ym), the primary 

effect is described by bulk density and particle size is not 

deeiined of further importance in the comparison of one coal pile 

to another. 

(3) Moisture— 

E0 ^

 a icJT (Referenc e 22) (B-7) 

SO M*--* 

_1_ 

'SO - (P-E) 

E"~ " (P-E) 2 (References 12, 22) (B-8) 

where M = surface moisture 

Entrainment rate is a function of particle size and a function 

of bulk density; these are treated as two independent 

variables. 

40 
P.56 

a 

P-E, which refers to Thornthwaite's precipitation-evaporation 

index, is only an approximation of surface soil moisture and is 

used because values for M are not readily available. 

ES0 " (P-E)2 (Reference 27) (B-9) 

(Here, E„n refers to tailings piles rather than soil.) 

E oe _ 2- (Reference 26) (B-10) 

Of all these factors, surface moisture is most important since 

it will tend tb suppress dust. The evaporation of moisture will 

likewise provide thermal currents which enhance dust formation. 

This action is similar to that occurring in soils and thus the 

P-E index as described by Thornthwaite, is a logical representation for surface moisture. 

Tjie empirical relationships shown here are for the most part very 

general approximations based on a variety of investigations. They 

may not be directly representative of conditions encountered in 

open coal storage. Thus, the accuracy and applicability of the 

results in the composite equation presented in the next section 

should be viewed with this in mind. Although quantitative 

relationships derived in this analysis may not be directly applicable to open coal storage, some conclusions concerning the 

relative importance of the various factors to coal dust entrainment are drawn by sensitivity analysis in Section 3.c. of this 

appendix. 

3. COMPOSITE EQUATION 

a. Development 

Based on the relationships presented in Section 2 of this 

appendix, the following quantitative expressions are judged to 

be most applicable to open coal storage: 

where- u = wind velocity 

where p, = bulk density 

Q cc u2.7-3.0 (B-ll) 

Q « Pb

2 (B-12) 

(27) Jutze, G. A., K. Axetell, and W. Parker. Investigation of 

Fugitive Dust - Sources, Emissions, and Controls. EPA 

Contract 68-02-0044, Task 9, U.S. Environmental Protection 

Agency, Research Triangle Park, North Carolina, May 1973. 

61 pp. 

41 
P.57 

Q H 0 .23 (B-13) 

where H = height 

Q * AL°•x 5 (B-14) 

where AT = leading angle in the prevailing wind direction 

Q =• V 0 .25 (B-15) 

where V = volume 

Q cc s 

0.35 (B-16) 

where s = surface area 

(P-E)-2 (B-17) 

Obviously, wind velocity, bulk density, and surface moisture (P-E 

index) are the most important factors influencing the open coal 

storage entrainment/emission rate, Q. 

The remaining variables: height, leading angle in the prevailing 

wind direction, volume, and surface area, describe coal pile 

geometry. Length and width, which also describe pile geometry, 

are deleted because they could not be adequately related to open 

storage entrainment; that is, they are not describable in a manner 

that would increase the usefulness of a quantitative expression. 

Judging by the similarity of the exponents attached to H, AL , V, 

and s, the factors determing coal pile geometry are all interrelated. For this reason, a single variable, s, was chosen to 

describe pile geometry. Considering the small magnitude of the 

exponents attached to s, H, A_, and V, entrainment rate is only 

slightly dependent on pile geometry. Based on these criteria, 

open coal storage entrainment is determined by the following 

expression: 

Q = k 

a b e 

u Pb s 

(P-E)z (B-18) 

where the exponents are expected to be in the range: 

2.7 < a < 3.0 

2 < b < 6 

0.15 < c < 0.35 

42 
P.58 

b. Comparison with Wind Erosion 

Both Woodruff (22) and Chepil (25) have described the process of 

wind erosion and the factors which affect soil erosion. The 

Woodruff equation is of the form: 

E = f (I', C , K', L', V ) (B-19) 

where I1 = soil and knoll erodibility index for different soil 

fractions 

C = local wind erosion climatic factor 

K* =' surface roughness 

L' =' unsheltered distance across the field along the 

prevailing wind direction 

V = vegetative cover 

„E = potential average annual soil loss 

This may be reduced to Equation B-20 by defining the variables 

through their appropriate algorithms. Thus: 

E = I«C»K»L»V (B-20) 

where I = f(I') (B-21) 

C = f(C) (B-22) 

K = f(K') (B-23) 

V = f(V) (B-24) 

L = f(L', I'K, I-OK) (B-25) 

,_ This form of equation is the same as the process described by 

t-P Woodruff and Siddoway (Equation B-19). Equations B-21, B-22, 

B-23, and B-24 are very direct relationships based completely 

upon independent variables which are not as complex for coal 

storage piles as they are for wind erosion. 

Parameter I can be related to the particle size distribution of 

the material being eroded. Furthermore, this particle size distribution can be related to the bulk density of the coal in a 

direct manner. Thus, for a size distribution, SD, 

I = ki(SD)a = k2Pb

b . (B-26) 

wher e SD = k 3 p b

b// a

 (B-27) 

o r SD a p,

 C (B-28) 

43 
P.59 

Equation B-26 gives a relationship of the basic erodibility for 

the source. As the particle size distribution range is reduced 

(from 840 ym to 7 ym), a smaller variation in I would be expected 

as one proceeds from site to site of a source. This has been 

borne out in the wind tunnel studies already completed on coal 

(2d, 23). 

The parameter C can be related wholly to the ratio of wind speed 

to iP-E index: 

C - k, (p ^)2 (B-29) 

The parameters K and V are related to ridge roughness and vegetation cover and for coal storage piles these can be equated to 

one since neither one is applicable. 

The length of the unsheltered field is the only complex variable 

whiph need be addressed. In Woodruff's system, the effect can be 

described by Equations B-30, B-31 and B-32. Woodruff used E2 

equal to the product of I and K, so that E2 may be set equal to I 

in these expressions. 

L = 1.0 (B-30) 

when E2 > 37,317 (L')°*751 (B-31) 

Otherwise L = k5 (L*)S E2

g (B-32) 

where L' = distance across field 

Combining Equation B-20, B-26, B-29 and B-30, the overall expression for E can pe described as: 

-< b u pb E = k2 k,, (p _ E

°

2 (B-33) 

Since Q is mass emission per unit time and E is mass erosion per 

area per unit time, Equation B-33 can be expressed: 

Q = Es (B-34) 

, b 

u

3pfa s 

Q =

 k6 (p-E)2 (B-35) 

where kg = k2»k*+ 

s = area Of pile 

44 
P.60 

If Equation B-32 is used instead of Equation B-30, then the overall expression for E becomes Equation B-37 since I may be substituted for E2 in Equation B-32 to yield Equation B-36. However, 

this can be further reduced to Equation B-38 with Equation B-26. 

L = k5(L')eI

g (B-36) 

u

3

P.

b<L')eIg 

E. = k2klfk5 - — -• (B-37) 

(P-E)2 

tl+a. U3 pb

(b+bg) (L')e 

E = ki1+g)kttk5 *- (B-38) 

(P-E)2 

For this study, the length of the exposed field, L', used by 

Woodruff can be equated to a parameter of the coal pile. Assuming 

that coal piles are square with an area of s, Equation B-39 can be 

combined with Equation B-38 to give the net relationship shown in 

Equation B-40. 

s = (L')2 (B-39) 

u

3 phm se / 2 

E = k7 (p_E )2 (B-40) 

where m = b + bg (B-41) 

k7 = k2

(1+g) ku k5 (B-42) 

Substituting for E (from Equation B-40) into Equation B-34, the 

overall relationship is obtained: 

•• m n 

u

dpb s 

Q -

 k 7 (p_E)2 (B-43) 

wher e n = | + 1 (B-44) 

Thus, either Equation B-35 or B-43 would describe the windblown 

emissions for coal piles depending upon the size of the pile. 

These equations compare favorably with the form of Equation B-18 

and confirm the validity of the form of emission expression given, 

By combining Equations B-31, B-39 and B-26, Equation B-35 may be 

considered valid when: 

45 
P.61 

Pb 

Vb 

j^T T (s)°-375l (B-45) 

otherwise the expression developed in Equation B-43 would be 

valid. Thus, for large coal storage piles, the expression for Q 

in Equation B-43 could be most appropriate. A regression of the 

expression in Equation B-18 with sampling data would resolve the 

correct exponents. 

c. Sensitivity Analysis 

The factors which affect coal storage pile emissions can be considered as bounded variables. Thus the emission equation will likewise be a bounded expression.. It is desired to express all results 

ultimately on an annual basis so that all factors should be annual 

mean values. The range of each of these factors is as follows: 

1.3 < u < 6.7 m/s average = 4.5 m/s 

0.64 < pfa < 0.86 g/m3 average = 0.80 g/m3 

7 < P-E < 179 average = 91 

4.0 < s < 5.3 x 105 m2 average = 4.0 x IO4 m2 

By selecting exponents for Equation B-18 the effect of each variable can be determined. A value for the expression is determined 

from average values to serve as a reference. The results of the 

sensitivity analysis are given in Table B-l. It is apparent that 

P-E index is by far the most important factor affecting the distribution of emissions from coal piles. The least effect is from 

density. The omission of density from the expression would result 

in a possible variation in emissions of as much as ±65%. Leaving 

P-E index out gives an unreal variation of ±8,500. The factors 

which affect the emissions are (in decending order of importance) 

P-E index, wind speed, area, and density. 

Since the P-E index affects the emissions the greatest, emissions 

can vary greatly with ambient temperature and precipitation. Without the effect of P-E index, emissions could vary by 350%; however, 

the normal variation in precipitation can exceed this in most parts 

of the U.S. Coupled with this is the normal fluctuation in ambient 

temperature at a specific site. Thus the variation in emission 

rate of a coal pile is greater at a specific site than it normally 

would be from one site to another. 

4. SUMMARY 

Equation B-18 is used in conjunction with the sampling results in 

Appendix A (Table A-2) to determine an analytical expression or 

the emission rate from coal storage piles (Equation A-5) which is 

reproduced as follows: 

46 
C-m- -Q £l 

TABLE B-l. SENSITIVITY ANALYSIS OF ENTRAINMENT/EMISSION RATES CALCULATED 

USING EQUATION B-18-1 WITH AVERAGE, MINIMUM, AND MAXIMUM VALUES 

FOR HIND VELOCITY, BULK DENSITY, P-E INDEX, AND SURFACE AREA 

Entrainment/emission rate fo) 

(Calculated using average, minimum or maximum values for independent variables as indicated) 

vliuL^orUll Wind speed, m/s Bulk density. g/cm3 Exponents* P-E index Surface area, m2 

variables u = 1.3 u = 6.7 p. = 0.64 0.86 P-E = 7 P-E = 179 a = 4.0 s = 5.3 x 105 

3.0 2.0 0.35 97 2.3 319 

A

c = 3.3 

62 112 

A = 0.52 

16,300 25 

4 = 170 

3.8 239 

A = 2.4 

3.0 6.0 0.35 40 0.95 131 

A = 3.2 

10.4 62 

A = 1.3 

6,680 10.2 

A = 170 

1.6 98 

A = 2.4 

-J*** 

2.7 2.0 0.35 

3.0 2.0 0.15 

61 

12 

2.2 180 

A = 2.9 

0.28 38 

A = 3.1 

39 71 

A = 0.82 

7.4 13.4 

A = 0.50 

10,400 15.9 

A = 170 

1,960 3.0 

A = 160 

2.4 152 

A = 2.4 

5.7 17 

A = 0.94 

Equation B-18: 

ku' 

Q = 

where 

[P^E) 

b sc 

(P-E)2 

Q = entrainment/ 

emission rate, 

mg/s 

k = constant = 336 

u = wind velocity, m/s 

pb = bulk density, g/cm3 

s = surface area, m2 

a,b,c = exponents 

P-E = PrecipitationEvaporation Index 

Average values for 

independent variables: 

u = 4.5 m/s 

Pb = 0.80 g/m3 

s = 4.0 x 101* m2 

P-E = 91 

A is calculated from: 

Tnax ~ Tnin 

avg 

where Qm a x = emission rate calculated 

using maximum values for 

independent variable 

0 . = emission rate calculated 

n using minimum value for 

independent variable 

Q = emission rate calculated 

9 using average values for 

all independent variables 
P.63 

„ 3np 2 0.3*t5 

b s Q = 336 (B-46) 

(P-E)2 

This expression can be used to predict emissions within 124%, 95% 

of the time over limited ranges of u, p^, s and (P-E) as described 

in Appendix A. Since this expression has limited use and it was 

not desired to pursue its development into a more universal equation, only its implications on the factors affecting emissions are 

used in this document. For relating emissions to these parameters 

an overall emission factor is used. 

48 
P.64 

APPENDIX C 

DERIVATION OF SURFACE AREA FROM HEIGHT OF COAL PILES 

The surface area of a coal storage pile is primarily a function of 

the amount of' coal stored. Functionally, this is determined as 

follows: 

s

 = ^ ">* > 

where s = surface area, cm2 

T = weight of coal stored, g 

p. = bulk density, g/cm3 

H = pile height, cm 

In the mass emission rate equation developed in Appendix B, s is 

used to relate all geometric parameters of coal piles. This 

assumes a dependence on the height of the coal pile. It has been 

stated that coal is generally piled 4.3 m to 8.8 m (14 ft to 

29 ft) high, averaging about 5.8 m (19 ft) (28). A random survey 

was conducted of 12 coal piles. The results, given in Table C-l, 

indicate a range of 2.4 m to 11.3 m (8 ft to 37 ft), with the 

average being 6.0 m (19.6 ft) which is within 3% of the reported 

data. For converting weight to surface area, a constant height of 

5.8 m (19 ft) is used. 

Pile shape, and thus height, is generally dependent on the weight 

of coal stored. The small piles usually associated with smaller 

boilers or coke plants are generally conical in form to facilitate 

handling. Conical storage does not require the use of auxiliary 

equipment such as bulldozers. In addition, the smaller plants are 

usually nearer to population centers, and space is at a premium. 

(28) Annual Report of Research and Technologic Work on Coal. 

Bureau of Mines IC-7518, U.S. Department of the Interior, 

Washington, D.C, 1949. p. 39. 

49 
P.65 

TABLE C-l. HEIGHT OF COAL PILES 

Site 

HI 2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

x = 6.0 

Hei 

m 

7»6 

6.1 

4.3 

6.1 

9.1 

3.0 

11 

8.2 

3.6 

6 d 

3.6 

2.4 

m or 19. 

ght 

ft 

25 

20 

14 

20 

30 

10 

37 

27 

12 

20 

12 

8 

6 ft 

The error in predicting the supply stored varies with the facility 

at which the coal is stored. For the three types of facilities 

considered, the errors are: 

Coke plants 23 days ± 43% 

Boiler plants 39 days ± 59% 

Utilities 93 days + 74% 

Based on the number of each type of facility, the overall weighted 

error introduced due to normal variations of tonnage stored is 

61%. The use of 800 kg/m3 (50 lb/ft3) for the density of coal 

introduces an additional error of 10%. By considering the coal 

pile height constant at 5.8 m (19 ft), the error is 26%. Thus the 

error introduced by the use of constant values for pfc> and H 

increases the error in the estimate of s by 36%. The overall error 

is 97% which is within the allowable limits for use in the emission 

rate equation (Appendix B). 

50 
P.66 

fmh 

I 

APPENDIX D 

SAMPLING EQUIPMENT AND PROCEDURES 

1. HIGH-VOLUME SAMPLING METHODS AND EQUIPMENT 

To perform the sampling required, high-volume samplers were positioned around the coal pile as shown in Figure A-l and A-2. The 

arrangement in Figure A-l permitted correlation with horizontal 

dispersion and sampler S3 would illustrate downwind power law 

decay. This arrangement was altered for later sampling to Figure 

A-2 when the observed concentrations were not sufficient to make 

these correlations. Nucleopore® membrane filters were used for 

sample collection due to their relatively low tare weight (500 mg) 

and high flow capacity (36 1/min-cm2, 93.3 kPa pressure drop) in 

comparison with similar filters. The lower tare weight and higher 

flow capacity enabled the particulate collected to comprise a 

higher percentage of tare weight and thus provide results that 

were within the measurable range. After particulate matter on the 

filters was weighed (subtracting the tare weight), the mass concentration of suspended particulate was computed from the volume 

of air sampled. The concentration of particulate collected at 

reference sampler S0 was subtracted from the concentration of the 

other samplers (Slf S2, S3, and S4) to yield the particulate concentration due to the coal pile emissions. The mass emission rate 

was determined using Turner's equation for a ground level source 

with no effective plume rise (16) as shown in Appendix A. 

A.Brink® impactor was used to determine the size distribution of 

the particles emitted. This unit has a relatively low sampling 

rate of ±5 x 10"5 m3/s (<_0.1 acfm) and small tare weight ( = 13 mg) 

in comparison with similar units. The percent of particles smaller 

than 5 ym captured by the Brink unit was used to estimate the 

weight of respirable particulates collected by the high volume 

samplers. Because of the low mass emission rate only one composite sample (two sample days) was collected. 

A meteorological station was employed to monitor wind speed, 

direction, and temperature. The median wind speed over a 1-minute 

time lapse, was recorded at 15-minute intervals. The mean wind 

speed was then calculated from the arithmetic average of the 

General Metals Works, Inc., Cleves, Ohio. 

51 
P.67 

15-minute readings over the entire run. Wind direction was 

similarly recorded every 15 minutes. If the direction varied by 

more than ± 0.78 rad (+ 45°) from the centerline for two consecutive 

recordings, then either: 1) sampling was terminated when the runs 

had proceeded for more than 4 hours, or 2) sampling was continued 

when the wind direction returned to within ± 0.78 rad (± 45°) if the 

run had proceeded for less than 4 hours. The standard of 4 hours 

was chosen since it is approximately the minimum time required for 

particulate collection to equal about 20% of the tare weight of the 

filter, the target minimum weight of collected particulate that can 

be measured. The minimum desired mass of particulate collected is 

a weight equal to one-half the tare weight of the filters. A 

sampling run of 8 hours was chosen in an attempt to achieve this 

goal. The ± 0.78 rad (± 45°) (from centerline) fluctuation of wind 

direction between two consecutive runs was chosen since greater 

variations have resulted in poor particulate collection. Quite 

often, changes of this magnitude result in frontal movement and 

rain or wind storms. 

Temperature values were read at the meteorological station within 

the accuracy of the instrument, which was ± 1.1°C (+ 2°F), and 

averaged for the week of sampling. Precipitation levels for the 

week were obtained from the nearest weather bureau in the area. 

Weekly values are utilized to determine the possible effect of 

these parameters prior to sampling. These effects are then 

accounted for by calculating a psuedo P-E index for the year from 

these weekly values. (A yearly index based upon weekly values, 

assumes that sample history for every week is identical to 

each and every other week, that is, the rain and temperature 

patterns are identical, for the year, to the selected weeks.) 

To determine the quantity of coal stored, the present inventory 

level at the plant was obtained from company records. Bulk density was obtained directly from tables relating density to the 

class of coal stored or from proximate analysis (supplied by 

the company). 

2. FILTER ANALYSIS PROCEDURES 

a. Concentrations 

High volume samplers are used to collect the particulate matter. 

Weights are determined to the nearest milligram, airflow rates to 

the nearest 5 x 10"3 m3/s, and time to the nearest 5 minutes. 

Mass concentrations are reported to the nearest yg/m3. At an 

average mass concentration of 128 yg/m3, the standard deviation 

is 5.12. 

Prior to sampling the unit was calibrated by use of a calibrating 

orifice assembly and water manometer. (These calibration units 

52 
P.68 

are adjusted with a positive displacement meter.) A chart was 

then drawn of airflow versus static pressure. After the orifice 

was attached to the unit the airflow was varied by the addition of 

perforated plates across the airflow stream. A calibration curve 

was then plotted relating airflow readings to actual flow in nonmetric units. 

Prior to sampling, each filter was inspected for imperfections, 

desiccated in a balance room, and weighed to the nearest milligram 

in a weighing chamber. The tare weight was then recorded and the 

filter holder labeled. Once sampling was completed, the volume 

was determined from the initial and final airflow readings. (These 

readings are converted to m/min through an appropriate calibration 

curve.) The volume of air sampled was determined as follows: 

(

Q

i

 + Qf) x fc

s 

va = 2 ^"D 

where v = air volume sampled, m3 

Q. = initial airflow rate, m3/min 

Qf = final airflow rate, m3/min 

t = sampling time, min 

Once the volume was determined and the final weight of the filters established (by the procedure previously mentioned), the mass 

concentration of particulates was determined by: 

W- - W.^ x IO6 (wf - w±) 

X = -i-: - (D-2) 

v 

a 

where X = mass concentration of particulate, yg/m3 

Wi = initial (tare) weight of filter, g 

Wj = final weight of filter, g 

va = volume of air sampled, m3 

106 = conversion of g to yg 

b. Composition 

After the filter is weighed, one portion is selected for microscopy examination and another for composition analysis. X-ray 

fluorescence was chosen to give a semiquantitative determination 

of particulate composition. 

(1) The Principle of X-Ray Fluorescence (XRF) Analysis— 

XRF analysis is based on measuring* individual,characteristic 

x-rays for each element in a sample by energy dispersive techniques. These secondary fluorescent x-rays are generated by 

irradiating the specimen with a primary source of x-rays using 

either a tungsten or rhodium target x-ray tube. All secondary 

x-rays are detected simultaneously with a silicon semiconductor 

detector. By using suitable amplifiers and an x-ray energy 

distribution analyzer, the characteristic x-rays for each element 

53 
P.69 

are electronically separated based on their energy and are displayed in either a spectral or alphanumeric mode via video monitor, 

The data are also stored in a computer memory for additional data 

improvement or for on-line computerized data reduction and presentation in a teletype print-out. 

An on-line computer is used for data reduction. Computer programs 

enable manipulation of spectral data to eliminate interfering 

lines, to integrate peaks, to subtract backgrounds, to correct for 

interelement and matrix effects, and to provide a variety of quantitative conversion equations to reduce raw counts to elemental 

concentration. 

(2) Applicability of XRF— 

The XRF technique is applicable to qualitative and quantitative 

elemental analyses (sodium to uranium) for solids (whole sections 

or powdered) and liquids (including solids in solution). In the 

specific case of particulate.collected on filters, the direct 

measurement of these specimens can provide a detection limit of 

<0.2 yg/cm2 with sample loadings of 1.2 yg/cm2. The detection 

limit is influenced by many factors including energy of the x-rays 

being emitted by the elements, matrix, counting times, excitation 

source, and sample chamber atmosphere. For particulate on filter 

paper with a loading of 1.2 yg/cm2 and with a rhodium excitation 

source, the following detection levels can be attained: 

Element 

P 

S 

K 

Ca 

Cr 

Fe 

Ni 

Cu 

Zn 

As 

Br 

Cd 

Ba 

Hg 

Pb 

Detection level, 

yg/cm2 

0.20 

0.11 

0.15 

0.06 

0.06 

0.05 

0.05 

0.05 

0.04 

0.04 

0.07 

0.13 

0.13 

0.08 

0.07 

(3) XRF Apparatus— 

The analytical system used in these measurements is composed of 

an EDAX International Inc. Mark II Basic EDAM System, EDAX Model 

707A Super Analyzing Unit, a Data General Corp. 12 K Computer 

(Nova 1220), and a Teletype 33TC. Either a rhodium or tungsten 

target x-ray tube is available. The system can be operated with 

54 
P.70 

1 

the sample maintained in vacuum or in a helium purged atmosphere. 

Samples up to 76 mm (3 in.) in diameter can be analyzed. 

(4) Calibration of XRF Equipment--

Quantitative analysis with the x-ray technique is based on using 

(a) reference standards of known concentrations of the desired 

elements in a matrix similar to that of the unknown specimens, or 

(b) mathematical corrections through computer programs to correct 

for interelement and matrix effects. 

If a range of standards is avilable, it is possible to establish 

a working curve for each element which is a plot of concentrations 

in micrograms (or yg/cm2) vs. the intensity of the x-rays characteristic of each element. If the range of standards is not available, the ratio of the intensity of the peak of unknown concentration of an element to the intensity of the peak of a known 

concentration of that same element will provide a reliable semiquantitative analysis (± £50% of the amount present). 

Standards are prepared by precipitation or deposition of NBS 

Standard Research Materials, metal oxides or salts, or portions 

of "loose" particulate collected during long-term sampling. In 

the latter case, emission spectrographic analysis of this material 

serves to provide the needed compositional information for preparing standards. Several deposition procedures are used for 

preparing semiquantitative standards including the filtration of 

particulate suspended in carbon tetrachloride and the filtrations 

of particulate suspended in gas matrix or deposited from solution. 

Other semiquantitative measurements of particulate collected on 

filters are made by correlating the x-ray fluorescence responses 

of test samples with emission spectrographic analyses of ash for 

one or more of the test specimens in a set. This correlation 

serves to provide a semiquantitative means of rapidly analyzing 

large numbers of filters by XRF without going through an ashing 

step, which is required for emission spectrographic analyses of 

filters with low loadings. 

(5) Procedure for XRF Analysis— 

Based on the type of sample matrix and the elements being measured, the excitation source and the x-ray excitation voltage are 

selected. Either a helium flush or vacuum is applied to the 

sample chamber, and proper selection of the energy range is made 

to optimize response. The filter specimen is analyzed by counting 

the secondary x-rays for 100 seconds to 2,000 seconds depending on 

quantity of material on the filter. 

The spectral data are manipulated by computer software to smooth 

the statistical channel-to-channel fluctuations in the spectrum, 

subtract background or spectra characteristic of residual trace 

elements in the filter, strip a series of peaks characteristic 

of specific elements, and obtain quantitative or semiquantitative 

55 
P.71 

data by comparing the spectral intensity of the test specimen 

with the known values of the standard samples. 

(6) Calculations— 

The computer provides the resulting values (quantitative or semiquantitative) in yg/cm2 or comparable notation as programmed. 

3. GAS SAMPLE ANALYSIS 

a. Collection Procedure 

Several grab samples were collected for analysis of total hydrocarbons, methane, carbon monoxide and total sulfur. A 250-ml 

Pyrex flask with a stopcock on each end was cleaned and filled 

with dry nitrogen. The top of one of the stopcocks was fitted 

with a rubber bulb and one-way flow valve so as to pull a vacuum 

on the Pyrex flask. The other stopcock was covered with cotton 

and inserted about 150 mm into the coal pile. Both stopcocks 

were then opened and about 1 liter of gas was pulled through the 

flask. The stopcocks were closed and the flask returned to the 

laboratory for analysis. 

b. Analysis of Total Hydrocarbons, Methane and Carbon Monoxide 

(1) Principle and Applicability— 

The method used in this analysis is a semicontinuous technique 

for measuring total hydrocarbons, methane and carbon monoxide in 

ambient air (29). Minor modification of electronics enables 

measurements from 0.1 ppm up to 2%. 

(a) Principle—Measured volumes of gas samples are delivered to 

a hydrogen flame ionization detector to measure total hydrocarbon 

content. An aliquot of the same gas sample is introduced into a 

stripper column which removes water, carbon dioxide, and hydrocarbons other than methane. Methane and carbon monoxide are 

passed quantitatively to a gas chromatographic column where they 

are separated. The methane is eluted first and is passed unchanged through a catalytic (nickel) reduction tube into the 

flame ionization detector. The carbon monoxide is eluted into 

the catalytic reduction tube where it is reduced to methane 

before passing through the flame ionization detector. Between 

analyses, the stripper column is backflushed to prepare it for 

the subsequent analysis. Hydrocarbon concentrations corrected 

for methane are determined by subtracting the methane value from 

the total hydrocarbon value. 

(b) Applicability—The method is applicable to the semicontinuous 

measurement of hydrocarbons, methane, and carbon monoxide in 

ambient air and in grab samples from emission sources. 

(29) Federal Register, 36(228), November 25, 1971. 

56 
P.72 

I (2) Apparatus— 

The instrument was designed and assembled by Monsanto Research 

Corporation personnel using design criteria that met Federal 

EPA specifications. Another model in this series was tested and 

found acceptable by the Federal EPA at Research Triangle Park, 

North Carolina. 

(3) Calibration— 

The instrument is calibrated with a series of methane and carbon 

monoxide standards prepared in synthetic air by Scott Research 

Labs. The values of instrument response vs. concentration of the 

standard gas samples are plotted. 

(4) Procedure— 

The sample is introduced into the system under the same conditions 

of pressure and flow rates as are used in calibration. Mathematical corrections can be made as needed for sample pressure differences (particularly when analyzing glass gas sampling tubes) by 

incorporating suitable pressure-volume relationships based on the 

ideal gas law. 

(5) Calculations— 

Concentrations of total hydrocarbons (as methane equivalents), 

methane, and carbon monoxide are determined directly from the 

calibration curves. No calculations are necessary, unless samplestandard pressure differences require corrections [see (4) above]. 

The concentrations of hydrocarbons corrected for methane is 

obtained by subtracting the methane concentrations from the total 

hydrocarbon concentration (as CH^). 

c. Analysis of Sulfur 

Several methods for sulfur analysis were attempted. Flame photometric and gas chromatographic analyses did not indicate substantial levels of any sulfur compounds even upon heating of the sample 

flask. The lower level of detection was 0.1 ppm. A variety of 

other procedures was also briefly investigated. 

4. SAMPLING GUIDELINES AND DATA SHEETS 

Guidelines and sampling data sheets used by field sampling teams 

for open sources are shown in Tables D-l, D-2, and D-3, and 

Figure D-l. 

57 
P.73 

TABLE D-l. OPEN SOURCES SAMPLING GUIDELINES 

1. Determine predicted wind direction and speed 

a. U.S. Weather Bureau 

b. Field estimate 

2. Determine atmospheric stability class expected - see Table 

on worksheet, (Figure D-l). 

3. Locate positions of samplers around source. Use guidelines 

for downwind distance (Table D-2). 

4. Place upwind sampler (background) and start sampling. 

5. Place wind instrument and downwind samplers for source 

monitoring. 

6. Wind direction and speed monitored every 15 minutes, 

stability class every 2-3 hours, note time sampler flow 

rates were checked at first 1/2 hour and then every 1-1/2 

hours. If wind direction is off centerline by more than 

0.78 rad (45°) in two consecutive readings, stop samplers 

until direction returns within 0.78 rad (45°) for 15 

minutes. 

7. Sampling completed in minimum sampling time determined by 

project leader. 

58 
_3 _ ! 

TABLE D-2 PLACEMENT OF SAMPLES DOWNWIND OF OBSTRUCTIONS 

vo 

Both the open source height and the obstructions must meet 

the required minimum distance criteria. 

1. 

2. 

3. 

Stability class is determined from cloud cover, wind speed, 

and time of day. 

The height of obstruction or source equals H. 

Stability 

Class 

A 

B 

C 

D 

E 

Other 

classes 

Minimum distance downwind 

from obstruction peak 

5H 

7H 

10H 

17H 

25Ha 

Cannot be done 

Requires an additional sampler at least 15H downwind for backup. 
TABLE D-3. FUGITIVE DUST SAMPLER AND METEOROLOGICAL DATA LOG 

o 

Time 

(24 hr. 

clock) 

Totals 

Average 

Total el 

Wind 

Speed Direction 

mph 

avg. 

apsed 

range 

time 

Compass 

degrees 

avg. range 

Sl 

Roto 

cfm 

Act 

cfm 

S2 

Roto 

cfm 

Act 

cfm 

Date 

S3 

Roto 

cfm 

Act 

cfm 

Run 

S4 

Roto 

cfm 

Act 

cfm 

Page 

Other comments 

Sampling crew 
P.76 

I 

©- T 

sourcTM1^e - - —1 

I 

T © © 

Id © 

B *«~C 

T 

reference 

line 

sampler 

centerline 

A 

B 

C 

D 

E 

P 

ft. (measured) 

ft. " 

ft. " 

ft. " 

ft. " 

ft- (estimated) 

ft. " 

actua l 

dry bulb 

wet.bul b 

Run No. 

DATE 

barometri c 

pressur e 

Op 

Op 

"He 

Op 

Op 

ATMOSPHERIC STABILITY DETERMINATION 

TIME 

II 

II 

£ 

CM 

m-t-m 

.•*-m 

a-mmm 

IX« 

m ---

stwiittr 'rn 

t 

• 

• 

• 

..orl.. 

STABILITY 

COMMENTS: 

Sampler 

S 

Filter No, 

Brinks sampler located next to S ' 

wind instrument is behind S, 

obtain sample of source before signing sheet 

Sampling 

crew 

Figure D-l. Fugitive dust sampling worksheet. 

61 
P.77 

APPENDIX E 

COMPUTATION OF COMBINED ERRORS 

The value of emission rate, Q, is determined in the field by 

application of Gaussian dispersion equations to the concentrations 

obtained at high volume samplers. These emission values have a 

standard deviation which is a function of the standard deviation 

of the variables. The emission rate is calculated using Turner's 

(14) estimates of atmospheric dispersion from ambient measurement 

of X. In such estimates, there is an error due to inconsistent 

airflow rates and there are errors in time measurements and weighing which are part of the emission error. 

The values of atmospheric stability as reflected by the standard 

deviations (a) in the horizontal and vertical planes are valid 

for a sampling time of 10 minutes. The vertical deviation is 

expected (14) to be correct within a factor of 2 for: 1) all 

stabilities out to a few hundred meters, and 2) neutral to moderately unstable conditions in the lower 1,000 meters of the atmosphere with a marked inversion above for distances out to 10 kilometers or more. Since all sampling was performed within a few 

hundred meters of the coal pile, these conditions were met. The 

estimate of horizontal dispersion, ay, will be less uncertain than 

that of oz. The emission determined will therefore be (for the 

three cases cited) within a factor of 3 for variations of av, oz 

and u (14). Hence, the overall standard deviation in determining 

emission rate can be estimated as follows: 

a = yjio^2 + (a2)

2 (E-1) 

where aj = estimated population standard deviation from 

sampling for X 

Oi - additional standard deviation in calculation of 

Q from X 

A factor of 3 is defined as follows: 

JrHf- - 3 (E-2) 

where X = any average value calculated or measured. 

62 
.rmmt 

"~m 

'"1 

•

r"____l 

j, • 

>-*-.'• 

1 

f'"f^m 

i • 

i -^B 

/^B 

'if 

). H 

(I 

'-y 

From Equation 

implies 

Example 1 

and 

Hence, 

and 

Example 2 

and 

Hence, 

then 

x. 

-

E-2, a factor of three in the calculation of Q 

a 2 = 0.5X. (E-2) 

X = 6.4 mg/kg-yr 

oi - 2.9 mg/kg-yr 

o2 - 0.5 (6.4) = 3.2 mg/kg-yr 

o = yj(2.9)2 + (3.2)

 2 = 4.3 mg/kg-yr 

X = 336 mg/kg-yr 

Oi = 200 mg/kg-yr 

a2 = 0.5 (336) =16 8 mg/kg-yr 

a = -^(200)

 2 + (168) 2 = 261 mg/kg-yr 

63 

P.78 

• 
P.79 

APPENDIX F 

DETERMINATION OF DISTANCE TO PLANT BOUNDARY AND 

POPULATION DENSITY FOR REPRESENTATIVE COAL STORAGE PILE 

A survey was conducted of the same 12 sites used to determine pile 

height (Appendix C). These sites were originally selected at 

random and cover the spectrum of coal storage users as shown in 

Table F-1. Values which are three standard deviations beyond the 

mean were discarded to achieve the means presented. Since this 

would normally bias the results; deviations were discarded in pairs 

(a high and a low). 

TABLE F-1. DISTANCE TO PLANT BOUNDARY AND POPULATION DENSITY 

FOR REPRESENTATIVE COAL STORAGE PILE 

Site 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

Mean (biased) 

Standard 

deviation 

Mean 

(metric units) 

Coal pile size, 

tons 

3,000 

73,000 

63,700 

42,000 

461,000 

280,000 

11,000 

50,000 

584,000 

45,000 

4,000 

3,000 

135,000 

198,000 

122 x 103 

metric tons 

Distance to 

boundary, 

ft 

440 

150 

200 

50 

500 

300 

50 

800 

2,600 

150 

10 

175 

288 

236 

86 m 

Population 

density, 

persons/mile2 

52 

1,060 

63 

58 

3 

1 

10 

68 

417 

42 

78 

4 

155 

306 

61 persons/km2 

64 
P.80 

fl 

APPENDIX G 

ANALYSIS OF COAL STORAGE PILES FOR 

POLYCYCLIC ORGANIC MATERIALS 

Two samples from coal storage piles were selected for analysis of 

polycyclic organic materials (POM' ) by chemical ionization mass 

spectroscopy. The results are shown in Table G-1. The first 

sample was from a coal storage pile at an open pit mine where the 

coal had been aged for about 10 days at the most. The coal seam 

where this coal originated is typical of western subbituminous coal, 

The second sample is from an Indiana coal seam and is typical of 

interior region bituminous coal. This sample had aged for approximately 60 days and shows measurable quantities of benzo(c)phenanthrene, benzo(a)pyrene and 3-methylcholanthrene. 

From Appendix A the average emission rate is 19 mg/s from coal 

storage piles. Taking an order of magnitude rise in a POM concentration (to account for unknowns) to 5 yg/g of coal, the emission 

rate (Q) for POM's would be 0.0095 yg/s. Severity is calculated 

using the noncriteria formula developed in Appendix H shown as 

follows: 

c = 316 Q 

(TLV) Dl • 814

 KK3 ±) 

For the POM calculation, the minimum representative distance (D) 

is 83 m and the TLV ,is 1 yg/m3. Thus, the severity is 0.0099 for 

a representative coal pile which is two orders of magnitude below 

the severity for coal dust. 

65 
P.81 

TABLE G-1. ANALYSIS OF COAL SAMPLES EXTRACTED WITH PENTANE 

FOR SELECTED POLYCYCLIC ORGANIC MATERIALS (POM'S) 

BY CHEMICAL IONIZATION MASS SPECTROSCOPY 

Polycyclic organic material 

Benzo(c)phenanthrene 

7,12-Dimethylbenz(a)anthracene 

Benzoi(a) pyrene 

3-Methylcholanthrene 

Dibenz(a,h)anthracene 

Dibenzo(c,g)carbazole 

Dibenzo(a,h)pyrene 

Dibenzo(a,i)pyrene 

Concentration, ppm (w/w) 

Open pit mine Indiana 

coal storage coal storage 

ND (<0.2) 

ND (<0.2) 

^0.2 

<0.2 

ND (<0.2) 

ND (<0.2) 

ND(<2) 

ND(<2) 

0.5 ± 0.1 

<0.2 

0.3 ± 0.1 

0.4 ± 0.1 

ND (<0.2) 

ND (<0.2) 

ND (<2) 

ND (<2) 

No signal was detected for the molecular weight plus one atomic 

mass: unit ions of these compounds at their respective retention 

times. 

Unidentified peaks which eluted prior to the appearance of the 

first polycyclic organic compound listed above were present in 

this sample. 

66 
P.82 

APPENDIX H 

DERIVATION OF SOURCE SEVERITY EQUATIONS 

1. SUMMARY OF MAXIMUM SEVERITY EQUATIONS 

The maximum severity of pollutants may be calculated using the 

mass emission rate, Q, the height of the emissions, h, or the 

distance from the source to the nearest plant boundary, D, and the 

threshold limit value, TLV. The equations summarized in Table 

H-l are developed in detail in this appendix. 

2. DERIVATION OF x FOR USE WITH U.S. AVERAGE CONDITIONS 

max 

The most widely accepted formula for predicting downwind ground 

level concentrations from a point source is (14); 

- „[ 4 (j-J].,. [.j( X = ^ .. expl-^ fi-) | exp l-if^] | (H-l) 

where X = downwind ground level concentration at reference coordinate x and y with emission height of h, g/m3 

Q = mass emission rate, g/s 

ay = standard deviation of horizontal dispersion 

az = standard deviation of vertical dispersion 

u = wind speed, m/s 

y = horizontal distance from centerline of dispersion, m 

h = height of emission release, m 

x = downwind dispersion distance from source of emission 

release, m 

u = 3.1416 

67 
P.83 

TABLE H-l. POLLUTANT SEVERITY EQUATIONS 

Pollutant Severity equation 

For elevated sources: 

Particulate 

SO. 

NO 

Hydrocarbons 

Carbon monoxide 

Other 

For ground level sources 

Particulate 

SO. 

x 

NO 

x 

Hydrocarbons 

Carbon monoxide 

70 Q 

h

2 

50 Q 

h

2 

315 Q 

h 2 . l 

162 Q 

h

2 

0.78 Q 

h

2 

5.5 Q 

TLV • h2 

4,020 Q 

D 1.8 1 

2,870 Q 

D 1.8 1 

22,200 Q 

D 1.9 0 

9,340 Q 

D 1.8 1 

44.8 Q 

nl-81 

Other 316 Q 

TLV ,1.81 

68 
P.84 

1 

We assume that Xm a x occurs when x >>0 and y = 0. For a given 

stability class, standard deviations of horizontal and vertical 

dispersion have often been expressed as a function of downwind 

distance by power law relationships as follows (30): 

°

y =

 ax 

a„ = cx + f 

z 

(H-2) 

(H-3) 

Values for a, b, c, d and f are given in Tables H-2 and H-3 (31). 

Substituting these general equations into Equation H-l yields: 

x = B+d- Tb exP 

acirux + affufx 

[ 2(cxd + f)2J 

(H-4) 

Assuming that Xmax occurs at x <100 m or the. stability class is C, 

then f = 0 and Equation H-4 becomes: 

acirux 

b+d exp L_dsL_l 

[2c2x

2d

_ 

(H-5) 

For convenience, let: 

AR = -0 - and BR = zHi 

aciru 2c2 

so that Equation H-5 reduces to: 

X = AR x"(b+d ) exp U

2 d J (H-6) 

(30) Martin, D. 0., and J. A. Tikvart. A General Atmospheric Diffusion Model for Estimating the Effects on Air Quality of One 

or More Sources. Presented at the 61st Annual Meeting of the 

Air Pollution Control Association, St. Paul, Minnesota, June 

23-27, 1968. 18 pp. 

(31) Tadmor, J., and Y. Gur. Analytical Expressions for the 

Vertical and Lateral Dispersion Coefficients in Atmospheric 

Diffusion. Atmospheric Environment, 3 (6) : 688-689, 1969. 

69 

V.m/ 
P.85 

TABLE H-2. VALUES OF a FOR THE COMPUTATION 

OF o„a (31) 

Stability 

A 

B 

C 

D 

E 

F 

class a 

0.3658 

0.2751 

0.2089 

0.1471 

0.1046 

0.0722 

For the equation 

oy - axb 

where x = downwind distance 

b - 0.9031 

TABLE H-3. VALUES OF THE CONSTANTS USED TO 

ESTIMATE VERTICAL DISPERSION3 (31) 

Stability 

Usable range, m class Coefficient 

ci di fi 

>1,000 A 0.00024 2.094 -9.6 

B 

C 

D 

E 

F 

0.055 

0.113 

1.26 

6.73 

18.05 

1.098 

0.911 

0.516 

0.305 

0.18 

2.0 

0.0 

-13 

-34 

-48.6 

C2 dj f2 

100 to 1,000 A 0.0015 1.941 9.27 

<100 

, 

For the equation 

B 

C 

D 

E 

F 

A 

B 

C 

D 

E 

F 

°z

 = 

0.028 

0.113 

0.222 

0.211 

0.086 

C3 

0.192 

0.156 

0.116 

0.079 

0.063 

0.053 

d __. * cx + f 

1.149 

0.911 

0.725 

0.678 

0.74 

d3 

0.936 

0.922 

0.905 

0.881 

0.871 

0.814 

3.3 

0.0 

-1.7 

-1.3 

-0.35 

70 
P.86 

I 

Taking the first derivative of Equation H-6 

ai • AR |*~b"

d

(-p [via3)(-2dV

2d-') 

+ exp[BRx-2d] (-b-d)x-b-d-ij {H_7) 

and setting this equal to zero (to determine the roots which give 

the minimum and maximum conditions of x with respect to x) yields: 

£ - 0 - ARx-b-d-' (exp [BRX-2<3] ) [-2dBRx-^-b.d] (H.8, 

Since we define that x / 0 or » at X_„av, the following expression 

must be equal to 0:

 ma x 

-2dBRx-2d-d-b =0 ( 

or (b+d)x2d (b+d)x = -2dB : 

(H-10) 

or 

2 d - -2dBR _ 2d h2 

or 

b+d 2c2(b+d) • (H-ll) 

-

2d

 = d h2 

~c2(b+d)

 (H"12> 

v - / d h2 \2d ^ or x - at x 

\c2(b+d)/

 ma x (H-13) 

Thus Equations H-2 and H-3 become: 

* \c2(d+b) ' 

71 
P.87 

a = cj

 d h' 2d

 =l±l£.)2 (H-15) 

z \c2(b+d)/ \b+d / 

The maximum will be determined for U.S. average conditions of 

stability. According to Gifford (32), this is when a = a . 

y z 

Since b = 0.9031, and upon inspection of Table H-2 (31) under U.S. 

average conditions, ay = az, it can be seen that 0.881 < d £ 0.905 

(class C stability3). Thus, it can be assumed that b is nearly 

equal to d or: 

<? = — (H-16) 

z /2 

and 

o = *- -£ (H-17) 

y c /I 

Under U.S. average conditions, ay = az and a = c if b = d and f = 0 

(between class C and D, but closer to belonging in class C). 

Then % = -Z (H-18) 

/2 

Substituting for ay and az into Equation H-l and letting y = 0: 

2 Q T l/h/2\2 

(H-19) 

or 

X =

 2 Q (H-20) 

max . o ireuhz 

The values given in Table H-3 are mean values for stability 

class. Class C stability describes these coefficients and 

exponents, only within about a factor of two (14). 

(32) Gifford, F. A., Jr. An Outline of Theories of Diffusion in 

the Lower Layers of the Atmosphere. In: Meteorology and 

Atomic Energy 1968, Chapter 3, D. A. Slade, ed. Publication 

No. TID-24190, U.S. Atomic Energy Commission Technical Information Center, Oak Ridge, Tennessee, July 1968. p. 113. 

72 
P.88 

1 

I 

For ground level sources (h = 0), Xm a x occurs by definition at the 

nearest plant boundary or public access. Since this occurs when 

y = 0, Equation H-l becomes: 

X - — (H-21) 

A

 TTO a u 

y z 

From the foregoing analysis of U.S. average conditions, class C 

stability coefficients are the best first approximations to U.S. 

average conditions when a = a . 

By letting D equal the distance to the occurrence of Xm a x (see 

Tables H-2 and H-3), 

a = 0.209 D0-

9031 (H-22) 

az = 0.113 D0-

911 (H-23) 

Thus, Xmax

 1 S determined as follows: 

Xmax " 42 -3 6 ° <H-24) 

TTUD

 i • ° 1 4 

It will be noted.that Equations H-24 and H-20 are identical with 

the algebraic substitution of 

h

2

 = 0.01737 D1>

8 l k

 (H-25) 

For U.S. average conditions u = 4.47 m/s so that Equation H-20 

reduces to: 

X = °-0524 Q (H-26) 

max h 2 

3. DEVELOPMENT OF MAXIMUM SOURCE SEVERITY 

The general source severity, S, relationship has been defined as 

follows: 

• S = £ (H-27) 

where x = mean ambient concentration 

F = severity factor 

73 
a. Noncriteria Emissions 

The value of x may be derived from Xmax , an undefined "short term" 

concentration. An approximation for longer term concentration may 

be made as follows (14): 

For a 24 hour time period, 

t \0-

17 

max \ 

^max V t_ / 

\ JJ / 

or 

Xl = Xm av HF M (H"28) 

(

3 min \ 

1,440 miny 

0*. 17 

x. - xmax (. _;-,„;„) (H-29) 

\

 m "max

 (0-35' (H3 0) 

Since the severity factor is defined and derived from TLV values 

as follows: 

F •WVioo) = (TLV) I^AlTJoj

 (H"31) 

. F = (3.33 x 10-3) TLV (H-32) 

then the severity factor, S, is defined as: 

Q XX (0>35)xmax 

S = — = — {H _ 3 3 ) 

F (3.33 x 10

 3) TLV 

105 x 

S = TLV

m a X (H-34) 

If a weekly averaging period is used, then: 

0.17 

X 2

 = 

Xmax f10,080 J (H-35) 

or 

X2 = (°-25)xmax (H-36) 

74 
P.90 

& 

and 

F

 - <TM> (IHXIW )

 (H

-

37) 

F = (2.38 x 10"3)TLV (H-38) 

and the severity factor, S, is: 

X (°-2 5 > xm a „ 

S = =± = — (H-39) 

F (2.38 x 10~3) TLV 

or 

105x 

s

 - -rar*

 (H

-

40) 

which is entirely consistent, since the TLV is being corrected for 

a different exposure period. 

Therefore, the severity can be derived from Xm a x directly without 

regard to averaging time for non-criteria emissions. Thus, 

combining Equations H-40 and H-26, for elevated source, gives: 

s

 - kthh <H-

41) 

b. Criteria Emissions 

For the criteria pollutants, established standards may be used as 

F values in Equation H-27. These are given in Table H-4. However, 

Equation H-28 must be used to give the appropriate averaging 

period. These equations are developed for elevated sources usinq 

Equation H-2 6. 

(1) CO Severity— 

The primary standard for CO is reported for a 1-hr averaging time; 

therefore, 

t = 60 min 

t = 3 min max 

(4)°-17 xmax

 xmax ' *n I (H-42) 

75 
P.91 

TABLE H-4. SUMMARY OP NATIONAL AMBIENT AIR 

QUALITY STANDARDS (33) 

Pollutant 

Particulate 

matter 

S O x 

Carbon 

monoxide 

Nitrogen 

dioxide 

Photochemical 

oxidants 

Hydrocarbons 

(nonmethane) 

Averaging 

time 

Annual (geometric 

mean) 

24-hourb 

Annual (arithmetic mean) 

24-hourb 

3-hourb 

8-hour 

l-hourb 

Annual (arithmetic mean) 

l-hourb 

3-hour 

(6 a.m. to 9 a.m.) 

Primary 

standards 

75 

260 

80 

365 

10 

40,000 

100 

160 

160 

ug/m3 

ug/m3 

ug/m3 

ug/m3 

-

mg/m3 

ug/m3 

ug/m3 

ug/m3 

ug/m3 

Secondary 

standards 

60a ug/m3 

160 ug/m3 

to ug/m3 

260c ug/m3 

1,300 ug/m3 

(Same as 

primary) 

(Same as 

primary) 

(Same as 

primary) 

(Same as 

primary) 

The secondary annual standard (60 ug/m3) is a guide for assessing implementation plans to achieve the 24-hour secondary 

standard. 

Not to be exceeded more than once per year. 

The secondary annual standard (260 ug/m3) is a guide for 

assessing implementation plans to achieve the annual standard. 

= 2 Q / 3\ °- 1 7 

ireuh2 \ 60 

_ 2_Q , n fiv 

" (3.14 ) (2.72 ) (4.5 ) h*

 KKJ't3> 

= 0^52_Q {Q6) 

_ (3.12 x 1Q-3)Q 

max 

Severity , S, = 

h

2 

x 

max 

(H-43) 

(H-44) 

(H-45) 

(H-46) 

(H-47) 

Settin g F equa l t o th e primary standar d for CO, i.e. , 0.04 g/m3 

yield s : 

S = 

xmax _ (3.12 x 10" 2

)Q 

0.04 h^ (H-48) 

o r 

CO 

0.78 Q 

h2~"' (H-49) 

(33) Code of Federa l Regulations, Titl e 42 - Publi c Health, 

Chapter IV - Environmental Protectio n Agency, Part 410 -

Nationa l Primary and Secondary Ambient Air Qualit y Standards, 

April 28, 1971. 16 pp. 

76 
P.92 

I 

i 

1 

I 

I x -x {-2-\ *max *max -V180 J 

(2) Hydrocarbon Severity— 

The primary standard for hydrocarbon is reported for a 3-hr averaging time. 

t = 180 min 

t__v = 3 min 

max 

0-17 

=

 0'5xmax 

(0.5) (0.052) Q 

(H-50) 

(H-51) 

(H-52) 

h

2 

0.026 Q 

xmax ~ ' (H

~

53) 

For hydrocarbons, F = 1.6 x 10'1* g/m3 

and 

s = W = 0.026 Q (R_5 4) 

* 1.6 x lO-^h2 

or 

S =

 162 >5 Q 

HC . 2 

(H-55) 

(3) Particulate Severity— 

The primary standard for particulate is reported for a 24-hr averaging time. 

\l,44o) 

0-17 

xmax = xmax i T~TTK) (H-56) 

= (0-052) Q (Q.3_5)_ (H-57) 

h

2 

w -

 (0-°"2) ° 

h

z 

77 
P.93 

For particulates, F = 2.6 x IO"4 g/m3 

s = xmax = 0-0182 Q (H-59) 

F 2.6 x IO"4 h2 

SB = ^-° - (H-60) 

P h2 

(4) SO Severity— 

The'primary standard for SO is reported for a 24-hr averaging 

time. 

- o (0-0182) Q ( 

max h2 

The primary standard is 3.65 x 10-4 g/m3 

and 

S = ^ £ - (0.0182)0 (H-62) 

F 3.65 x IO"4 h2 

or 

50 Q sso - —f (H63) 

x h'' 

(5) NO Severity— 

Since NOx has a primary standard with a 1-yr averaging time, the 

Xmax correction equation cannot be used. As an alternative, the 

following equation was selected: 

[-»ft) 1 x= i ^ui r

 ex Pl- ^ ( M l <H

-

6 4> 

A difficulty arises, however, because a distance x, from emission 

point to receptor, is included and hence, the following rationale 

is used: 

2 0 

The equation x.-Y = — 

max . 9 ueuh'' 

78 
P.94 

is valid for neutral conditions or when a =o„« This: .maximum 

occurs when

 y 

h =/2a 

z 

b 

a = ax 

z 

then the. distance x where the maximum concentration occurs is: 

IUciX 

i 

1 

1 

S and since, under these conditions, 

I 

I 

I 

I 

I 

I 

I 

<.*... I 

I 

| 

I 

I 

I 

I 

1 

x = /Jl_\ b 

max .- I 

\/2a / 

For class C conditions, 

a = 0.113 

b = 0.911 

Simplifying Equation H-64, 

since a = 0.113 x 0*911 

z max 

and u = 4.5 m/s 

Letting x = x in Equation H-64, ^ max 

[• »«) 1 *

 =

 x 1.91 1

 SX P

 I " TfTTM I (H-65) 

max 

h L 0 98 

Xmax = 0TT6- (H "6 6 > 

Xmax = 7 '5 hl * ° 9 8

 (H" 6 7 ) 

4 Q _ 4 Q 

a n d

 ~ nm " ( 7 5 ^1.098)1.91 1 < H-

6 8> 

xmax U. D n ; 

•[•»W 1 

- _ 0.085 Q , _,.., , 

X

 " h 2 . l

 6XP I " 2 I " ) I (H-69) 

° z = 0.113x0^1 1 (H . 7 0 ) 

79 

U 
P.95 

a = 0.113 (7.5 hl-l)0.9U (H-71) 

z 

a = 0.71 h (H-72) 

z 

Therefore 

'•[" * (oTTn;) ] - .. O^^a e^|- 1 /UL_ ^ | (H-73) 

= °-0 8 5 Q (0.371) (H-74) 

h2.l 

3.15 x 10

 2 Q 

X = • — ; 

h

2 -1 

(H-75) 

Since the NO standard is 1.0 x 10~4 g/m3; the NO severity equa-

• « X 

tion is: 

(3.15 x IO"2) Q S = ^•3

'

x

-

3

 x -i-v -) \_ (H-76) 

NO , - n-f. 

x 1 x 10

 H 

S N 0 = 315 Q (H-77) 

x K2.1 

80 
P.96 

1 

i 

i 

i 

i 

i 

i 

I 

l 

I 

i 

i 

i 

I 

| 

| 

I 

GLOSSARY 

active coal pile: aggregates of bituminous or subbituminous coal 

stored without any coating to prevent oxidation. 

asphyxia: loss of consciousness as a result of too little oxygen 

and too much carbon dioxide in the blood. 

atmospheric stability class: categories used to describe the turbulent structure and wind speed of the atmosphere. 

avalanching: the continuous deposition and resuspension of loose 

soil particles blowing across a field. 

background level: concentration of pollutants in the air prior to 

the addition of pollutants from the source of interest. 

Brink samples: particle size distributed samples of particulate. 

calibrating orifice assembly: a unit connected to the inlet of a 

high volume sampler for calibration. 

catalytic reduction tube: a device used for conversion of carbon 

monoxide to methane via a nickel catalyst for detection by 

flame ionization chromatography. 

chemical ionization mass spectroscopy: method of chemical analysis 

in which ions are passed in a vacuum first through an accelerating electric field and then through a strong magnetic field. 

chromatographic column: long tube packed permeably with some 

absorbent for separating components of mixtures. 

clump detachment: bulk dispersal of particle deposits from a dust 

pile in a wind tunnel. 

coal tar derivatives: black, viscous liquids obtained from the 

destructive distillation of coal. 

coal erodibility: capacity of coal for disintegration. 

cohesive deposits: dust piles of coal with a particle size range 

of 6 ym to 8 ym. 

81 
composite TLV: threshold limit value of a compound based on the 

concentrations and threshold limit values of each of the 

elements. 

confidence level: the probability that a random variable lies 

within a specified range given a known distribution of that 

variable. 

confidence limits: upper and lower boundaries of values that a 

random variable lies between with a specific probability. 

criteria pollutant: pollutant for which ambient air quality standards have been defined. 

elevated sources: sources with a point of emission above ground 

level. 

emission burden: ratio of emissions from a source to the total 

emissions per state or nation. 

emission factor: emission rate divided by coal storage pile 

capacity. 

entrainment rate: rate of material dispersal from a dust pile. 

flame ionization detector: device which measures the electrical 

conductivity of a flame. 

flame photmetric: emission of radiation (photons) by an element 

in a flame. 

free-flowing deposits: dust beds containing particles in the size 

range of 100 ym to 150 ym. 

gross particulate: the entire quantity of respirable particulates 

considered as inert, nuisance particulates. 

hazard factor: toxicity of a pollutant corrected for a 24 hr 

exposure with a safety factor of 100. 

impact factor: a factor which shows the relative environmental 

impact of emission sources for use in assigning priorities in 

investigative work. 

implementation plans: procedures for achieving ambient air quality 

standards. 

inactive coal pile: coal stockpile coated with a tar derivative to 

prevent oxidation. 

insolation class: a categorization for various levels of incoming 

solar radiation. 

82 
P.98 

Im 

mass coal dust: respirable suspended particulate which is found in 

coal mines, as differentiated from ambient particulate matter. 

noncriteria pollutants: pollutants for which ambient air quality 

standards have not been established. 

Nucleopore: a polycarbonate filter medium. 

open sources: , fugitive sources which do not have a definable point 

of emission such as a stack or vent. 

pneumoconiosis: any of various diseased conditions of the lung 

characterized by fibrous hardening as a result of chronic 

inhalation of irritating dust particles. 

quartz: a brilliant, crystalline mineral as silicon dioxide. 

radiation index: a reference to the amount of incoming sun rays 

that strike the earth's surface. 

respirable range: all of those particulates less than 7 ym in 

diameter. 

sensitivity analysis: mathematical technique in which the effect 

of one parameter is observed over a range of possible values 

while the remaining parameters are kept constant. 

spectrographic analysis: study of the dispersal of light into a 

spectrum passing through a medium. 

stripper column: a column in series with the analytical column 

which H20, C02, and hydrocarbons (ex. CH^) are removed. 

Thornthwaite*s P-E index: a relationship expressing the amount of 

precipitation and the mean temperature in a given region. 

weathering: erosive effects of the forces of weather on a coal 

pile. 

X-ray fluorescence: analytical technique in which x-rays are 

absorbed depending upon the wavelength and the material. 

83 

y 
P.99 

TECHNICAL REPORT DATA 

(Please read Instructions on the reverse before completing) 

1. REPORT NO. 

EPA-600/2-78-004k 

3. RECIPIENTS ACCESSION NO. 

4. TITLE ANO SUBTITLE 6. REPORT OATE 

May 1978 issuing date 

SOURCE ASSESSMENT: COAL STORAGE PILES 6. PERFORMING ORGANIZATION CODE 

7. AUTHOR(S) 

T. R. Blackwood and R. A. Wachter 

8. PERFORMING ORGANIZATION REPORT NO. 

MRC-DA-504 

9. PERFORMING ORGANIZATION NAME ANO ADDRESS 

Monsanto Research Corporation 

1515 Nicholas Road 

Dayton, Ohio 45407 

10. PROGRAM ELEMENT NO. 

1BB610 

11. CONTRACT/GRANT NO. 

68-02-1874 

1? SPONSORING AGENCY NAME ANO ADDRESS 

Industrial Environmental Research Lab-Cinn., OH 

Office of Research and Development 

U.S. Environmental Protection Agency 

Cincinnati, Ohio 45268 

13. TYPE OF REPORT ANO PERIOO COVEREO 

Task Final, 5/74-9/75 

14. SPONSORING AGENCY. COOE 

EPA/600/1? 

IS. SUPPLEMENTARY NOTES 

IERL-Ci project lead 

513/684-4417 

for this report is John F. Martin, 

16. ABSTRACT 

This report describes a study of atmospheric emissions from coal storage 

piles. Fugitive emissions of dust and gases are emitted from coal storage 

piles. The average emission factor for respirable particulate (<7 ym) 

is 6.4 mg/kg per annum; this factor describes the emission rate 95% of the 

time within 108%. From the distribution of coal piles, a representative 

pile was selected containing 95,000 metric tons of bituminous coal. The 

emission rate from this pile averages 19 mg/s or 610 kg/yr. In order to 

evaluate the potential environmental effect of coal storage piles, a 

severity factor was defined as the ratio of the maximum ground level concentration of an emission to the ambient air quality standard for criteria 

pollutants and to a modified threshold limit value for other pollutants. 

Severity factors for a representative coal storage pile are 0.025 and 1.0 

when the emissions are treated as gross particulate and coal dust, respectively. The national emission burden from all coal storage piles is 

0.00048% of total national particulate emissions. The amount of coal 

stored is increasing at the rate of 3.8% per year and this will result in 

a 25% increase in emissions in 1978 compared to 1972. Air pollution control techniques for coal storage piles have not been generally established 

and no future control techniques are presently under consideration r 

17. KEY WORDS ANO OOCUMENT ANALYSIS 

DESCRIPTORS 

Air Pollution 

Coal 

Dust 

Gases 

b.lOENTIFIERS/OPEN ENOEO TERMS 

Air Pollution Control 

Stationary Sources 

Source Severity 

Particulate 

c. COSAT I Field/Group 

68A 

18. DISTRIBUTION STATEMENT 

RELEASE TO PUBLIC 

19. SECURITY CLASS (This Report/ 

UNCLASSIFIED 

2 1. NO. OF PAGES 

90 

20 SECURITY CLASS (This page) 

UNCLASSIFIED 

22. PRICE 

EPA Form 2220-1 l»-7J) 

84 

&U.J. GOVDMMOITnwnuieoniCI. 19n—7S7-MQ/68S1