&EPA
United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Cincinnati OH 45268
EPA-600/7-78-081
May 1978
Research and Development
Environmental
Assessment of Coal
Transportation
nteragency
Energy/Environment
R&D Program
Report
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7 Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
effects; assessments of, and development of, control technologies for energy
systems; and integrated assessments of a wide range of energy-related environ-
mental issues.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/7-78-081
May 1978
ENVIRONMENTAL ASSESSMENT OF
COAL TRANSPORTATION
by
Michael F. Szabo
PEDCo Environmental, Inc.
Cincinnati, Ohio 45246
Contract No. 68-02-1321
Project Officer
John 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
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DISCLAIMER
This 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.
11
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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 develop-
ing and demonstrating new and improved methodologies that
will meet these needs both efficiently and economically.
This report deals with primary and secondary environ-
mental impacts resulting from transportation of coal by
slurry pipeline, railroad, barge, truck, and conveyor. The
information developed herein characterizes the pollution
problems and thus becomes important as a planning and design
tool for transportation systems. Agencies involved in
energy systems planning, and individuals conducting research
in the areas of coal mining and coal movement and utilization
should find this publication to be of value. For further
information contact the Resource Extraction and Handling
Division.
David G. Stephan
Director
Industrial Environmental Research Laboratory
Cincinnati
in
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ABSTRACT
As a result of an increase in U.S. coal production to
help achieve energy independence, much attention is being
focused on regional-scale transportion of coal in volumes
projected to reach 1.32 billion metric tons (1.2 billion
tons) in 1985. Most transportation studies to date have
centered on economics. Equally important, however, are the
possible environmental impacts due to both normal operation
and catastrophic events associated with preparation and
transportation of coal.
Work described herein deals with (1) primary and secondary
environmental impacts resulting from transportation of coal by
slurry pipeline, railroad, barge, truck, and conveyor; (2)
coal preparation and associated activities, such as loading
and unloading, and (3) energy efficiencies of the transport
modes. Many of the environmental impacts can be lessened by
improvements in control technology; most of these impacts
are not critical in terms of health and welfare; some,
however, such as toxic properties of effluents from coal
preparation plants, storage piles, and slurry lines, need
further characterization. Dewatering and treatment of coal
fines from slurry lines are troublesome aspects of slurry
line operation. Emergency procedures in the event of break-
age of slurry lines must be better defined. Other factors
critical to the future of slurry lines are availability of
water in the semi-arid western states and eminent domain
legislation. Uses of energy associated with the transport
modes should receive consideration in planning of coal trans-
portation systems.
This report is submitted in fulfillment of Task 40 under
Contract 68-02-1321 by PEDCo Environmental, Inc., under the
sponsorship of the U.S. Environmental Protection Agency. The
report covers a period from February 1976 through December 1976,
and work was completed as of November 1977.
IV
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CONTENTS
Foreword iii
Abstract iV
Figures vi
Tables viii
Acknowledgment x
1. Introduction 1
2. Background Information on U.S. Coals and 3
Methods of Mining Preparation
Definitions, grades, specifications 3
Reserves-Resources 4
Methods of mining and preparation 8
Coal use 10
3. Review of the Coal Transportation Industry 13
Coal transportation methods 13
1985 projections for coal production and 45
transport modes
Summary of coal transportation costs 45
Energy requirements for coal transportation 50
4. Environmental Impacts Associated with Coal 59
Transportation
Impacts from coal preparation and associ 59
ated activities
Impacts from coal slurry pipelines 64
Impacts from railroad transport of coal 73
Impacts of barge transport of coal 81
Impacts from overland belt conveyor 84
transport of coal
5. Recommended Research and Development of Control 93
Technology
Coal cleaning 93
Coal storage 95
Crushing, loading, and unloading 95
Coal slurry pipelines 95
Railroads 97
Trucks 98
References 100
Appendices
A. Groundwater resources and the relationship to 105
use of coal slurry pipelines
B. Comparison of costs of transportation methods 117
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FIGURES
No. Page
2-1 U.S. coal reserves, classified according to
geographic area and type of mining 6
2-2 U.S. coal uses, 1950-1985 12
3-1 Status of coal slurry pipelines in the U.S. 15
3-2 Black Mesa pipeline from mine site to Mohave
Terminal 18
3-3 Coal preparation plant for the Black Mesa
pipeline 19
3-4 Typical size distribution of present coal used
in the Black Mesa pipeline 21
3-5 Examples of coal cars used in unit trains 24
3-6 Flood loading in a conical pile ground-storage
system 27
3-7 Typical open storage single conical pile 28
3-8 Enclosed trench storage pile 28
3-9 Typical unit train loading from a silo 29
3-10 Frond-end loading on a rail car 30
3-11 Illustration of a rotary car coal dumping system 32
3-12 Link belt unit-train car dumper 32
3-13 Unit-train unloading by use of trestle system 33
3-14 Coal handling combines high-capacity unloading
and ready storage with automated reclaim 33
3-15 Radac gas-fired Infra-red thawing system in use
at Electric Utility generating station 35
VI
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Figures (continued)
No. Page
3-16 30 Barge tow on the lower Mississippi River 36
3-17 Barge-unloader elevator carriage showing trans
verse and longitudinal drives for scopping
patterns 38
3-18 Continuous-bucket elevator transferring coal
to conveyor system for outside live storage 38
3-19 A portion of the Kayenta mine conveyor belt
in Arizona 39
3-20 Cost of transporting coal by truck 42
3-21 Typical truck used on-site at a coal mine 43
3-23A Origin and movement of coal - 1975 46
3-23B Origin and movement of coal - 1975 47
4-1 Earthern impoundment for control of dust from
coal storage piles 61
4-2 Loading station for unit train 63
4-3 Photo of Black Mesa line as it exits from a 69
pump station
4-4 Combustion heat loss as a function of coal
moisture content 70
4-5 Unloading of a hopper car from a unit train 76
4-6 Example of fugitive dust from unloading at
a coal mine 90
4-7 Dust from haul roads at a coal mine 90
A-l Abundance of water in the U.S. 106
A-2 Upper Missouri Basin 108
A-3 Major coal, oil shale, and river systems in 111
the Upper Colorado River Basin
vii
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TABLES
No. Page
2-1 Summary of Demonstrated Coal Reserve Base of the
United States 7
3-1 Current and Proposed Coal Slurry Pipelines 16
3-2 Unit Train Movements of Bituminous Coal and
Lignite 26
3-3 Coal Barge Traffic on Rivers Serving the Appala-
chian Region, 1973 34
3-4 Truck Shipment of Bituminous Coal, by State, 1973 41
3-5 Estimates of U.S. Coal Transport by Mode for
1975 and 1985 48
3-6 Summary of Cost of Transporting 75 Million Tons
of Coal Per Year a Distance of 1000 Miles 49
3-7 Energy Requirements of Various Coal Transport 51
Modes from Published Sources
3-8 Summary of Estimated Energy Requirements, Black
Mesa Coal Slurry Pipeline 53
3-9 Summary of Estimated Energy Requirements for
273 Mile Unit Train Haul of 3,765,000 Tons of
Coal Annually 54
3-10 Summary of Estimated Energy Requirements for
273 Mile Barge Haul of 3,765,000 tons of
Coal Annually 55
3-11 Summary of Estimated Energy Requirements for
Truck Transport of Coal 56
3-12 Summary of Estimated Energy Requirements for
Conveyor Transport of Coal 57
vi 11
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TABLES (continued)
No. Page
3-13 Estimated Energy Requirements of Various Coal
Transportation Systems 58
4-1 Atmospheric Emissions from Coal Preparation and
Associated Activities 65
4-2 Atmospheric Emissions from Unit Train on
985-km Round Trip 75
4-3 Summary of Atmospheric Emissions in Barge
Transport of Coal 82
4-4 Atmospheric Emissions from Truck Transport of
Coal 89
5-1 Priorities for Research and Development of
Environmental Controls for Coal Transportation 94
A-l Estimated Supply/Demand for Upper Colorado River
Water in the Year 2000 112
B-l Rail Rates for Unit Trains Western Railroads -
1974 119
B-2 Barge Transportation Rates - 1970 120
B-3 Costs and Resources for Unit Trains 125
B-4 Costs of Slurry Pipeline in Comparison to Rail 127
B-5 Rail Freight Rates - 1975 129
B-6 Rail-Car Freight Rates - 1975 130
B-7 Levelized Rail Freight Rates - 1980 130
B-8 Levelized Rail-Barge Rates - 1980 131
B-9 Pipeline Transportation Costs Figures for 1980
Initial Operating Date 132
B-10 Excalation Factors for Annual Costs 133
B-ll Annual Levelized Utility Owning and Operating 134
Costs Thousands of Dollars
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ACKNOWLEDGMENT
This report was prepared for the Industrial Environmental
Research Laboratory (IERL), U.S. Environmental Protection
Agency, by PEDCo Environmental, Inc., Cincinnati, Ohio. The
project director was Mr. Timothy W. Devitt; the project
manager and author was Mr. Michael F. Szabo. Principal
investigators were Messrs. Jim Burke, Charles Hewitt, Thomas
Janszen, Michael Szabo, and Edward Zawadski.
The author appreciates the assistance and cooperation
provided by Mr. Martin, Mr. J.G. Montfort, President, Black
Mesa Pipeline Company, Flagstaff, Arizona, and Mr. M.L. Dina,
Plant Engineer, Mojave Generating Station, Southern Cali-
fornia Edison Company.
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SECTION 1
INTRODUCTION
The purpose of this project is to identify the poten-
tial environmental impacts associated with coal transporta-
tion and the methods available or potentially feasible for
controlling or reducing the impacts. Where the available
methods are inadequate for control, PEDCo recommends research
and development programs aimed at developing effective
control systems.
Coal is extracted by surface or underground mining. It
then undergoes some type of preparation, such as crushing
and/or cleaning, before delivery to the consumer. The
extent of preparation is determined by the quality of the
coal as mined, the quality desired by the consumer, and the
mode of transport. If the coal is to be transported by
slurry pipeline, for example, preparation may be much more
extensive than if it is to be shipped by train. Section 2
discusses specifications of U.S. coals, mining technology,
coal preparation, and end use of coal.
The mode of coal transportation is often dictated by
physical conditions such as terrain, climate, water resources,
navigabilty of waterways, road conditions, and distance of
transport. Railroads carry most of the coal that is trans-
ported over long distances (>160 km (>100 miles)); barges
carry the second largest quantities over long distances.
Although coal slurry pipelines are capable of long-distance
transport, only one pipeline is now operating. Trucks,
conveyor belts, and pneumatic pipelines are functional over
relatively short distances. Trucks are the major haulers
over short distances because of their versatility and the
widespread availability of public roads. Use of conveyor
belts is increasing greatly because of recently developed
technology, such as eddy-current clutches that control motor
speed and torque to maintain proper belt tension over long
distances. Use of pneumatic pipelines may increase as the
technology advances.
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Cost is another major factor determining transport
mode. If, for example, a railroad right-of-way now runs
from near the mine mouth to the consumer area, transport by
rail probably will be less expensive than construction and
operation of a slurry pipeline. Without an existing rail-
road right-of-way, however, operation of the pipeline may be
cheaper. Lastly, energy use affects the choice of transport
mode. Comparisons of energy use should be based on energy
demands of the total system that moves the coal, not on the
demands of the transport portion alone. Section 3 describes
the several modes of coal transport, changes in use of these
modes over the past 25 years, and their costs and energy
requirements.
Each method of mining, preparation, and transportation
of coal causes impacts upon the environment that vary in
intensity and duration. These impacts occur during construc-
tion, operation, and abandonment of the systems. Often
these impacts can be minimized or even eliminated by proper
precautions. Section 4 discusses the environmental impacts
of coal preparation and transport and the available control
technology-
Most of the environmental impacts of coal transport can
be mitigated. Some of them, however, are as yet undefined,
such as the toxic properties of coal slurries and of runoff
from coal storage piles. Section 5 concerns the impacts of
each transport mode for which the current control methods
are inadequate, the major areas of needed information, and
priorities for research and development.
There is currently much controversy regarding the
compatibility of slurry pipelines and railroad transport.
There is controversy also, especially in the central western
states, as to whether water resources are sufficient to
support pipeline requirements without depriving other pre-
sent and projected demands for water. Appendix A deals with
water availability in the central-western states and the
implications for coal slurry pipelines.
Appendix B presents a detailed discussion of recent
cost studies on coal transport.
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SECTION 2
BACKGROUND INFORMATION ON U.S. COALS AND METHODS OF MINING
PREPARATION (1)
DEFINITIONS, GRADES, SPECIFICATIONS (2,3)
Coal, like wood and peat, contains carbon, hydrogen,
oxygen, nitrogen, sulfur, and other constituents in small
quantities. The proportions of these major constituents
differ greatly in different grades of coal. For practical
purposes, however, coal is categorized by "proximate"
analyses, which are empirical tests, or by ultimate analysis,
which is a more complete determination of coal composition.
A proximate analysis of coal involves determination of
four constituents: 1) moisture; 2) ash, the residue from
complete combustion; 3) volatile matter, consisting of gases
or vapors driven off when coal is heated at 960°C for 7
minutes; and 4) fixed carbon, the solid residue that remains
after the volatile matter is driven off, less its ash content.
An ultimate analysis of coal indicates the contents of
ash, carbon, hydrogen, sulfur, nitrogen, and oxygen, calcu-
lated by difference. Moisture, sulfur, and ash are un-
desirable constituents. Volatile matter and fixed carbon
produce most of the energy when coal is burned.
The heating value of coal is generally expressed in
British thermal units (Btu) per pound or kilocalories per
kilogram. One Btu is the amount of heat needed to raise the
temperature of 1 pound of water from 60°F to 61°F. One
kilocalorie equals 3.9685 Btu.
In ascending order of rank, coals are classified as
lignitic, subbituminous, bituminous, and anthracitic. Rank
increases as the amount of fixed carbon increases and as the
amounts of inherent moisture and volatile matter decrease.
The great variation in composition of coals is apparent in
the following analyses, on an ash-free basis, of a typical
lignite and an anthracite, in percent:
1
Information in this section is largely abstracted from
Bureau of Mines Publications.
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Lignite Anthracite
Fixed carbon 33 92
Volatile matter 26 5
Moisture 41 3
Total 100 100
When exposed to air, lignite loses moisture and crumbles,
so that precautions must be taken in storage. Because its
heating value is lower than that of bituminous coal, pri-
marily owing to its high moisture content, the shipment of
unprocessed lignite over long distances is uneconomical. It
is generally used in areas near the mines.
Bituminous coal is the most abundant and widespread
coal in the United States. It is used most commonly for
industrial purposes, power generation, and space heating.
Coal is categorized also in terms of its coking properties,
which determines whether it will produce a hard cellular
carbon residue (coke) when heated to a minimum of 1500°F in
the absence of air. Nearly all eastern bituminous coals
have coking potential but those that contain excessive ash
or sulfur are not suitable for metallurgical purposes.
Western bituminous coals generally are noncoking and free
burning.
Both coking and noncoking coals soften when they are
heated, and volatile gas and vapors are released. When
coking coals are heated to 1500°F or higher in a sealed
oven, coke is formed after most of the volatile constituents
have been driven off. Coke is a dull-gray, porous, carbon-
aceous mass, consisting largely of fixed carbon and ash.
Under similar heating conditions, noncoking coals generally
produce weak chars or powdery residues. Noncoking and
coking bituminous coals may be used interchangeably as a
fuel in some power plants, depending on the design charac-
teristics of the combustion unit.
RESERVES-RESOURCES (4,5,6)
The U.S. Geological Survey (USGS) has identified re-
sources containing over 1542 billion metric tons (1700
billion tons) at depths of less than 915 meters (3000 feet).
On the basis of geological knowledge and theory, USGS
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personnel estimate additional U.S. coal resources of over
1995 billion metric tons (2200 billion tons). To indicate
the great magnitude of these resources, they cite the U.S.
production in 1975 of 0.58 billion metric tons (0.64 billion
tons).
The Bureau of Mines estimates that of the 1542 billion
metric tons available at depths less than 915 meters,
approximately 396 billion are in deposits of the type and
depth considered amenable to current mining and economic
conditions. Table 2-1 summarizes these deposits, which the
Bureau considers as the demonstrated coal reserve base of
the United States. Approximately two-thirds is in deposits
normally minable by underground methods, and the remainder
is in deposits minable only by surface methods. Figure 2-1
depicts the geographic location of these reserves and the
applicable type of mining.
'Reserve* coal is that which is recoverable. Recover-
ability of a deposit ranges from 40 to 90 percent according
to the characteristics of the coalbed, the mining method,
and the legal restraints on mining. Mining experience in
the United States indicates that nationwide at least half of
the underground in-place coals can be recovered.
The sulfur content of U.S. coals also varies consid-
erably. Although 46 percent of the total reserve base is
identified as low-sulfur coal (generally containing less
than 1 percent sulfur), 21 percent contains 1 to 3 percent
and an additional 21 percent contains more than 3 percent
sulfur. The sulfur content of 12 percent of the coal
reserve base is unknown, largely because many coal beds have
not yet been mined.
Sulfur content of coals significantly affects the
future siting of mines and of plants that will utilize coal.
Approximately 84 percent of the Nation's reserves of low-
sulfur coal are in the western States(5,6).
In 1974, the World Energy Conference and U.S. Geolog-
ical Survey estimated world resources of 'hard' coal at
nearly 80 percent of all in-place resources. Hard coal
includes all coals of higher rank than lignitic or 'brown'
coal. Hard coals, including anthracite (amounts of which
are not given separately), are estimated at 9009 billion
metric tons (9933 billion short tons); brown coals and
lignite are estimated at 2418 billion metric tons (2666
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s
u
R
F
A
C
E
U
N
D
E
R
G
R
0
U
N
D
WEST
103
0.85%S
9,787
BTU/LB
1.01%S
10,455
BTU/LB
131
234
EAST
34
2.20%S
12,412
BTU/LB
169
203
2.37%S
12,228
BTU/LB
(FIGURES IN BILLIONS OF TONS)
BUREAU OF MINES
U.S. DEPARTMENT OF INTERIOR
Figure 2-1. U.S. coal reserves, classified
according to geographic area and type
of mining (1) .
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Table 2-1. SUMMARY OF DEMONSTRATED COAL RESERVE BASE
OF THE UNITED STATES (1)
(Billion short tons)
Rank of Coal
Bituminous
Subbituminous
Lignite
Anthracite
Total
Underground
mining
reserve
base
192
101
0
7
300
Surface
mining
reserve
base
41
68
28
a
137
Total
233
169
28
7
437
Estimated total
heat value
(quadrillion Btu)
6,100
2,800
400
200
9,500
Less than 1/2 unit,
Metric conversion: 1 ton = 0.90718 metric ton.
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billion short tons). Total in-place resources of all ranks
of coal are estimated at 11,427 billion metric tons (12,599
billion short tons). The United States is said to have
approximately 31 percent of world coal resources. Note
however, that because the several nations that report coal
resources do not use the same criteria, the reported values
are not directly comparable.
METHODS OF MINING AND PREPARATION
Current underground coal mining is characterized by a
variety of specially designed mechanical cutting and loading
devices, such as mobile loading machines, continuous mining
machines, and longwall equipment. Continuous mining machines
have replaced mobile loaders at many locations, and in 1974
these machines cut and loaded nearly two-thirds of the coal
extracted underground.
The rapidity of coal extraction by continuous mining
makes it imperative that haulage be well-coordinated with
extraction and loading operations. Short, supplemental belt
conveyor systems, which move coal from continuous mining
machines to the main haulage system are now used extensively
instead of shuttle cars. Considerable improvement of under-
ground haulage methods is needed to keep pace with the high
productivity of continuous mining machines, which often must
halt operation while the coal is moved from the face of the
seam.
Development of methods of controlling respirable dust
continues. Several new collection and spray systems, foams,
and wetting agents were introduced in 1974 and 1975. New
bits and cutting systems also offer potential for dust
control„
In strip mining, the trend is toward larger equipment,
particularly for removing overburden and for loading and
hauling the coal.
Haulage trucks are becoming larger, more powerful, and
more versatile. One of the more promising trends in design
of off-highway coal haulers is the integration of the power
and drive trains and the payload body into a single-unit
chassis, in contrast with the conventional tractor trailer
design. The largest size haulage trucks currently in use
are 100 ton units.
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To negotiate slippery roads, difficult grades, and
tight turns, all-wheel-drive haulage units are becoming
increasingly popular. An articulated chassis is being
incorporated on some all-wheel-drive units to reduce tire
wear.
Conveyor belts also are being used more widely at
surface-mining operations. As annual tonnages and haulage
distances increase, the costs of installing and operating
conveyor belts become more favorable. Some operators of
surface mines are considering use of shiftable and portable
conveyor systems in the pits, as is now done in some European
operations.
Tractor-scrapers are proving versatile in both produc-
tion and reclamation operations. They are widely used at
western and Appalachian mines for removing and stockpiling
topsoil and other suitable materials that are later replaced
on graded mined lands. At some surface mines tractor-
scraper units are the primary means of removing overburden.
As the use of units of this type increases, more efficient
power trains and other improved design features are being
introduced.
Bucket wheel excavators are a valuable reclamation
tool. In the relatively flat land of the Midwest, these
excavators are used to remove topsoil and upper layers of
overburden. Power shovels then remove the remaining drilled
and blasted strata above the coal bed. In Illinois, these
wheel-shovel units are used as often as draglines to remove
primary overburden.
In Appalachia, new methods have been introduced to meet
regulations relating to highwalls and slopes in surface
mining. In West Virginia, in 1975, more than 20 surface
mining companies used or were planning to use haulback
techniques. Although the haulback concept is not new, it
has been tried only recently on long, steep slopes. Blasting
must be precise, and well-controlled, so that no material
goes down the slope; the overburden is then hauled from the
working site in trucks for use as backfill in nearby worked-
out areas. This practice often reduces the amount of
disturbed lands by up to two-thirds.
About 41 percent of the bituminous coal and lignite
produced in 1975 was mechanically cleaned. Cleaning equip-
ment consists of a variety of jigs, tables, launders, dense-
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medium and flotation washers, and pneumatic devices. With
all of these devices, separation depends on the difference
in specific gravities of coal and impurities. Selection of
a specific method depends on the size of coal to be cleaned,
its composition, and the chemical quality specifications
imposed by the consumer. In general, American coals are
easy to clean except when the sulfur is structurally bound
in the coal matrix as organic compounds, or is present as
finely divided pyritic (inorganic) compounds. Some coal can
be crushed to free the coarse pyritic sulfur, but as the
particle size becomes smaller, separation becomes more
difficult and costly- Coal preparation equipment is techni-
cally well advanced and is commercially available.
Design features of coal preparation units using gravity
separation are fairly well established. Improvements in
design and operating features will permit thorough separa-
tion, including greater reduction of pyritic sulfur. The
demands of the metallurgical market will impose increasingly
stringent requirements on grades of coal, especially in
regard to sulfur content. Similarly, electric utilities,
which constitute coal's major growth area, are being required
to burn low-sulfur coals until they can meet air pollution
control regulations either by reducing the sulfur content of
coals or by removing sulfurous pollutants from flue gases.
Some of the coal preparation processes being developed by
private industry appear to be nearing technical feasibility.
COAL USE
Consumption of coal by electric utilities in 1975 far
outranked all other uses, accounting for 73 percent of
domestic coal consumption. Between 1968 and 1975, coal
demand by electric utilities increased by 98 million metric
tons (108 million tons), or 37 percent. In 1975, coal
firing produced 43 percent of the total power generated and
55 percent of the total generated from fossil fuels.
Next in importance to electric power generation is the
use of coal in the primary metal industry, principally in
production of coke for the steel maker's blast furnaces.
Production of coke from coal generates useful byproducts,
including sulfur, ammonia, light oil distillates, and coal-
tar derivatives. In other industrial markets, coal is used
principally in industries producing food, paper, chemicals,
stone, clay, glass, and cement. Coal consumption in house-
10
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hold and commercial markets has declined steadily since the
early 1940's, when the average was 109 million metric tons
(120 million tons) annually, to less than 5 million metric
tons (6 million tons) in 1975. Figure 2-2 illustrates coal
usage in 1950 and 1975, with projections to 1985.
11
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C/5
z
o
1200
1000
800-
600-
400-
200-
480
1.025
INDUSTRIAL/
& /& •
RETAIL,/^/
•
' CO /
ELECTRIC
UTILITIES
1950
1975
1985
BUREAU OF MINES
U.S DEPARTMENT OF INTERIOR
one ton = .9071847 metric tons
Figure 2-2. U.S. coal uses, 1950-1985(1).
12
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SECTION 3
REVIEW OF THE COAL TRANSPORTATION INDUSTRY
Coal transport methods are discussed in this section,
followed by projections to 1985 of U.S. coal production and
use of the several transport modes. Costs and energy require-
ments of the transport modes comprise the remainder of this
section.
COAL TRANSPORTATION METHODS
Coal Slurry Pipelines
Although the earliest coal slurry pipelines covered
short distances, their operation indicated deficiencies in
design and materials. The knowledge gained from operation
of these pipelines has led to new designs and has made
pipeline operation competitive with other means of long-
distance transport.
In 1957, the Consolidation Coal Company of Ohio pioneered
in operation of long distance slurry pipelines. Their 25.4-
cm (10-in.)-diameter pipeline ran 174 km (108 miles) from a
mine in Cadiz, Ohio, to the East Lake Power Plant of the
Electric Illuminating Company. The system operated success-
fully for 6 years, carrying approximately 1 million metric
tons (1.1 million tons) of coal per year. Shutdown of the
line resulted from a reduction of rail tariffs on all coal
leaving District 8 in Ohio; this reduction made the system
economically impractical.
The only other commercial system is the Black Mesa
pipeline, which began operations in 1970 and is the longest
slurry pipeline in use today- Peabody Coal Company operates
the 46-cm (18-inch)-diameter pipe, which at full capacity
transports approximately 4.5 million metric tons (5 million
tons) of coal per year over a distance of 437 km (273 miles)
from the Black Mesa coal field in Arizona to the Mohave
generating station in Nevada. Black Mesa is the only coal
pipeline currently operating in the United States.
13
-------
The well-established eastern transportation routes can
readily absorb future increases in coal demand. Mining of
western coal, however, is in the early stages of development
and demand is increasing rapidly. Transportation routes
must be constructed and must be designed to minimize adverse
environmental impacts. In this respect slurry pipelines
constitute an attractive option.
Pipeline systems now in the planning stage will traverse
the West over distances ranging from 290 to 2030 km (180 to
1260 miles). The most advanced system under development is
the 1660-km (1030-mile) pipeline being undertaken jointly by
Energy Transportation Systems, Inc. (ETSI, an affiliate of
Bechtel), Lehman Brothers, and the Kansas-Nebraska Natural
Gas Company. The proposed 96.5-cm (38-inch)-diameter pipe-
line is to run from Wyoming to Arkansas, moving 22.7 million
metric tons (25 million tons) per year of coal at full
capacity. The longest pipeline planned is a 107-cm (42-
inch) -diameter line running 2030-km (1260-miles) from the
Powder River basin in northeastern Montana to the Houston
area of Texas. The Northwest Pipeline Corporation (Salt
Lake City, Utah) has considered the possibility of a 76-cm
(30-inch)-diameter pipeline hauling 14.5 million metric tons
(16 million tons) per year over 1610 km (1000 miles) from
Wyoming to Oregon. Others now in planning include a 1770-km
(1100-mile) pipeline from Colorado to Texas, and a 290-km
(180-mile) line to move coal in Utah to a power plant in
Nevada. Figure 3-1 shows current and planned pipelines in
the United States; Table 3-1 summarizes the pipeline data.
Coal Preparation for Slurry Transport --
For successful transportation in slurry form, the coal
must be prepared to a specific size without excessive
deviation from that size.
Coal preparation criteria for the line operated by
Consolidation Coal Co. (Consol.), in Cadiz, Ohio, were based
on pilot work conducted by the company. The specifications
were ultimately patented and were established as follows:
all coal must be ground smaller than No. 4 mesh, with 18 to
33 percent by weight less than 325 mesh, less than 60 percent
larger than 28 mesh, and the remaining material smaller than
18 mesh.
A coal strip mine operated by the Peabody Coal Company
in Kayenta, Arizona, supplies coal to the Black Mesa Pipeline
14
-------
\ VM
'N \^
1 l"^i'H-:—...
INTERSTATE
NORTHWEST , MONTANA/HOUSTON,''
PIPELINE 'V PIPELINE /
v S .' /
Legend
Existing
In progress
~~~~ Planned
Figure 3-1. Status of coal slurry pipelines in the U.S. (7) .
-------
Table 3-1. CURRENT AND PROPOSED COAL SLURRY PIPELINES (7)
System
Length, km (mi)
Pipeline
diameter, cm (in.)
Annual throughput,
million metric tons
(million tons)
Black Mesa
Nevada Power
Northwest
Energy Transportation
Wytex
Houston Natural
Salt River
439 (273)
290 (180)
1770 (1,100)
1667 (1036)
2510 (1560)
1784 (1109)
290 (180)
46 (18)
61 (24)
51 (20-24)
96.5 (38)
46-122 (18-48)
20-71 (8-28)
41 (16)
4.5 (5)
9 (10)
9 (10)
22.7 (25)
19-34.5 (21-38)
13.6 (15)
3.6 (4)
-------
Company for slurry preparation and transportation to the
Mohave Generating Station. Figure 3-2 depicts the pipeline
system from the Black Mesa Mine site to the Mohave terminal.
The coal supplied to the Black Mesa Pipeline Company is
sized at 5.1 cm x 0 (2-inch x 0).
Heating value of the coal as received from the mine
site ranges from 1.34 million g-cal/kg (11,700 Btu/lb) to
2.58 million g-cal/kg (12,600 Btu/lb), with an average of
2.55 million g-cal/kg (12,300 Btu/lb). Ash content ranges
from a low of 6.5 percent to a high of 17 percent, with an
average of 9.8 percent. Sulfur content ranges from 0.38
percent to 0.43 percent, with an average of 0.40 percent.
The moisture content of the coal as delivered to the pipe-
line company is 10.74 percent (9).
Coal is prepared according to the flow diagram shown in
Figure 3-3. From a transfer tower located at the mine site,
the coal is conveyed to one of three 536-metric ton (590-
ton) cylindrical bunkers. A variable-speed belt feeder
conveys the 5 x 0 cm (2x0 inch) coal to a two-deck vibrating
screen with capacity of 263 metric tph (290 tph). Coal
sized at 0.6 cm (+1/4 inch) is retained on the screens, then
is fed to an impactor and crushed to -0.6 cm (-1/4 inch).
The coal that passes through the screens is combined with
the impactor product, then supplied with water. Slurry
density is controlled by a densimeter. The coal/water
slurry is fed to a rod mill, then screened through 0.32-cm
(1/8-inch) screens. The oversize material is recirculated
through the mill. The -0.32-cm (-1/8-inch) material is
stored in one of four 2.46-million-liter (650 , 000-gal.)
tanks equipped with agitators. No coal fines are discharged
in this system. The coal is not cleaned to reduce ash or
sulfur contents.
The maximum and minimum pumping rates are 600 metric
tph (660 tph) and 510 metric tph (560 tph) respectively.
The maximum pumping rate is equivalent to pumping 265 liters/
sec (4200 gpm) of coal slurry at a density of 48 percent
solids by weight; the minimum pumping rate is equivalent to
pumping 237 liters/sec (3750 gpm) of coal slurry at 46
percent solids.
The Black Mesa pipeline began operation with coal
having the following approximate size distribution: 2
percent greater than 14 mesh, 82 percent 14 x 325 mesh, and
16 percent less than 325 mesh. The fines content was
increased to 20 percent because plugging occurred during
17
-------
00
KAYENTA PUMP STATION NO. 1
3 UNITS
Figure 3-2. Black Mesa pipeline from mine site to Mohave Terminal (8).
-------
AUTOMATIC SAMPLER
36" MILL FEED
COXVEYOR. 10 HP
x 45' SLURRY STORAGE-TAKKS
120 AGITATORS
• 125 H?
ROD MILL
DISCHARGE
SUMP
ROD MILL
DISCHARGE PUMP
US HP
Figure 3-3. Coal preparation plant for the Black Mesa pipeline (10).
-------
attempts to restart the line after shutdown. A typical size
distribution of the current coal is illustrated in Figure 3-
4.
Four pumping stations move 590 metric tph (650 tph) of
coal at a rate of 6.4 km/hr (4 mph). The three-unit stations
(Nos. 1, 3, and 4) operate at about 70 kg/cm2 (1000 psi),
and the four-unit station (No. 2) operates at about 105
kg/cm2 (1500 psi). The driving power is 1300 or 1120 kW
(1750 or 1500 hp) depending upon location. A dump pond and
water supply are provided at each station in case an emer-
gency should necessitate clearing the line. The dump pond
would hold the upstream slurry and the water supply would be
used to flush the downstream section.
Dewatering - Black Mesa Line --
Upon arrival at Mohave, the coal slurry is stored in
four active storage tanks with a capacity equivalent to 4
days total station full-load operation, approximately 117.3
million liters (31 million gallons). A 373-kW (500-hp)
mechanical agitator with a double paddle is operated in each
slurry tank to maintain the solids in suspension. Slurry
from the tank is pumped into Dynacone centrifuges (a total
of 20 for each unit), where it is dewatered. The coal cake
(at 20 percent moisture) is conveyed to the unit's 10
pulverizers, where it is dried and then transported to the
furnaces pneumatically. Gas burners are used in the primary
air ducts to increase the primary air temperatures from 343°
to 400°C (650° to 750°F). The 400°C (750°F) air is hot
enough to prevent plastering of the pulverizer and coal
pipe and to maintain a nominal temperature of 80°C (175°F)
at the pulverizer outlet.
Effluent from the centrifuges (centrate) containing a
portion of the coal fines is pumped to the clariflocculators
and is chemically treated to separate the coal fines from
the water. The treated coal fines (underflow) are then
pumped directly to the furnace at the top two burner eleva-
tions by means of underflow guns at each of the eight
corners of each boiler. The moisture content of the under-
flow is 80 percent. The overflow water is pumped to the
circulating water-cooling system. Excess clarified water is
diverted to large evaporating ponds. No liquid discharge is
permitted.
20
-------
100<
90
LU
X 80
I/O
Q
^ 70
o
CQ
-------
Water Supply --
The Black Mesa pipeline uses water supplied from seven
deep wells and an emergency resevoir. The wells are located
at depths between 1067 and 1128 m (3500 and 3700 ft) and are
encased in concrete to a depth of 610 m (2000 ft) (11). The
wells are drilled deep and the casings are used to protect
the shallow-well ground-water supply for domestic consumption,
Other Aspects of Coal Slurry Pipelines —
1. Corrosion control - A primary maintenance item in
coal slurry pipelines is pipe replacement. Corrosion inhibi-
tors may be added to the slurry to minimize corrosion. The
literature identifies a number of inhibitors. Consolidation
Coal Co. patented a process that involves the addition of 12
ppm each of a chromate and a polyphosphate together with a
pH above 6, to control corrosion (12) . The patent claims
that the chromate is removed from the water by fine coal
present in the clarifiers. Others claim the use of 10 to
1000 ppm of chromate coupled with organic phenols, poly-
acrylamides, or alkylene oxides for corrosion control.
2. Viscosity control - The literature also cites the
use of polyalkylbenzenes to adjust the viscosity of coal
slurries. The effect is to increase coal tonnage by a
significant percentage.
Coal Slurry Combustion —
1. Without dewatering - Consolidation coal has patented
a process that utilizes coal slurry as a fuel without de-
watering. The important features of the process are as
follows (13):
a. A suspension of particles of which 40 percent are
larger than 0.85 mm can be transported in 34
percent water and subsequently burned.
b. This slurry can be burned in a cyclone burner
provided the particles are in the size range of 0
to 3 mm.
c. Factors that affect the stability of combustion of
this slurry include particle size distribution of
the coal and the aerodynamic structure of the
coal-water stream injected into the boiler; an
undesirable combination of these factors causes
large particles to fall out without satisfactory
combustion.
22
-------
Others have studied combustion of coal slurries (14,
15). The consensus is that combustion is good but that heat
losses are large because of water evaporation and loss of
sensible heat. Another difficulty in firing of fuel with
high moisture content is the potential that the temperature
of the mixture could drop below the acid dew point. This
could cause significant corrosion.
This study does not consider the economics of direct
coal-slurry firing as opposed to dewatering and pulverized-
coal firing.
Railroads
Introduction --
Railroads move approximately 70 percent of the coal
produced in the United States. Although this movement
entails significant environmental problems, rail transport
offers several advantages.
Single-car loading is practiced at the smaller coal
mines. Empty hopper cars are parked at the mine site and
loaded as ordered. Crew efficiency and equipment utiliza-
tion are low since the crew and locomotive units must make
two trips for only a few cars.
Most coal shipped by rail is moved by multiple-car
loading, which is practiced at medium to large mines.
Although this system is somewhat more efficient than single-
car loading, the cars still must be sorted at intermediate
terminals.
The most efficient method of rail transportation is by
unit trains, which can serve medium and large mining opera-
tions. The unit train consists of a series of large-capacity
coal cars, typically hauling 9100 metric tons (10,000 tons)
of coal; such a unit train would consist of one hundred 91-
metric-ton (100-ton) cars. Examples of these large cars are
shown in Figure 3-5. The concept has revolutionized coal
handling by providing nonstop service for both producers and
users (14).
Shipment by unit trains requires facilities for rapid
loading and unloading, with associated stockpiling and
dedicated railroad equipment. From 1969 through 1973, unit
train tonnages increased in 14 of 21 coal producing states.
Western States gained nearly 18 million metric tons (20
23
-------
4,000-CU FT CAPACITY HIGH SIDE GONDOLA
t !
10' - 7 7/8"
I
A
I
1
1
1
I
47' 2 1/8"
I
12'- 2 13/16"
4,000-CU FT CAPACITY OPEN TOP TRIPLE HOPPER CAR
10' 7 7/8" C
48' 11 1/2"-
^' 8 1/2"
1 '^r-c^-
Metric conversion: 1 ft. = 0.3048 m
Figure 3-5. Examples of coal cars used in unit trains (16)
24
-------
million tons), which represents a 350 percent gain, while
states east of the Mississippi River gained only 12 million
metric tons (13 million tons) or an 11.5 percent gain.
Table 3-2 shows a time series of unit train loadings by
State from 1968 through 1973.
Loading --
Unit trains are loaded either at the plant-flow rate or
by flood-loading. In loading at normal plant rate, booms
and chutes are used to direct the output into the cars; coal
is not accumulated in storage. This was the early approach
to train loading, and even for unit-train shipment some
operations still find the plant-flow rate acceptable. In
most unit train operations, however, coal is accumulated in
storage and then flood-loaded as shown in Figure 3-6.
Storage for unit train flood-loading is in open piles
on the ground or in silos or bins (17). Ground storage is
the most common method of accumulating the supply necessary
for high-speed unit-train loading. Conveyors are generally
used for piling and reclaiming, but truck transportation is
used occasionally -
By far the most popular form of open-space storage is
the single conical pile, as shown in Figure 3-7. The pile
may be situated directly over a loading station as in Figure
3-7 to minimize handling of the coal. In this case a
fabricated steel tunnel with earth piled around it forms the
base for the pile. The loading chute is located in the
center and is designed to accommodate different size cars
and different loading rates.
Limitations include a small live storage capacity,
possible spillage in the tunnel, and fugitive dust emissions
from the large open pile. Also, the pile is open to public
view and is exposed to the weather.
In a simple form of ground storage, a conveyor dumps
the coal into a conical pile over a conveyor gallery equipped
with one or more feeders to move the coal when loading
starts. If dozing and dead (unused) coal are to be minimized
or eliminated, fabricated walls or earth embankments sloped
at 40 to 45 degrees may be used. Partial enclosure of the
pile will also lessen its visual and environmental impacts.
Figure 3-8 illustrates an enclosed-trench storage pile.
25
-------
O^
Table 3-2. UNIT TRAIN MOVEMENTS OF BITUMINOUS COAL AND LIGNITE
(THOUSANDS OF NET TONS) (18)
State
Eastern:
Alabama
Arkansas
1 1 1 i no i s
Kentucky East
Kentucky West
Total Kentucky
Maryland
Ohio
Pennsylvania
Tennessee
Virginia
West Virginia
Total eastern
Western:
Colorado
Indiana
Iowa
Kansas
Missouri
Montana (Bitum. )
New Mexico
North Dakota (Lig. )
Oklahoma
Utah
Wyoming
Other
Total western1-3
Grand totalb
1968
13,363
8,537
4,864
13,401
10,477
18,054
5,372
42,289
102,956
731
a
a
1
a
5,435
6,167
109,125
1969
2,257
40
17,621
7, 420
6,845
14, 265
150
13,014
20,370
5,067
40,733
113,517
1,336
1,913
96
365
2
742
787
934
2,031
8,206
121,722
1970
3,088
17,217
9,361
8,762
18,123
232
13,308
21,325
398
5,861
30,110
109,662
2,427
2,997
3,022
1,130
916
974
2,055
107
13,628
123,289
1971
3,373
89
17,329
11,164
7,730
18,894
210
16,688
19,125
1,343
2,525
26,793
106, 369
1,692
2, 351
762
6,526
1,034
923
910
1,825
441
16,464
122,832
1972
4,253
21,777
9, 522
6,706
16,228
60
18,063
18,228
1,171
3, 301
33,446
116,527
1,210
3,048
378
214
7,698
623
1,577
462
1,905
2,889
20,004
136,534
1973
3,930
22,155
12,197
7, 291
19,489
122
18,266
22,262
1, 208
4,477
34 , 203
126,111
2,391
5,493
190
10,115
778
1,607
489
2,094
5,826
28,983
155,094
Included in "other".
Totals may not add because of independent rounding.
Metric conversion: 1 ton - 0.90718 metric ton.
-------
Figure 3-6. Flood loading in a conical pile
ground-storage system (17).
Source: 1974 Keystone Coal Industry Manual
27
-------
ifju.vc 3-7. Typical open storage single conical pile (17) .
Storage building
Travelling rotary plow
Figure 3-8. Enclosed trench storage pile (19)
28
-------
The silo loading system has many desirable attributes.
The silos generally range in capacity from 9072 to 13,600
metric tons (10,000 to 15,000 tons). These silos accomodate
the necessary volume with a minimum of ground space and
eliminate losses of windblown coal dust, which may be a
major consideration in certain localities. Protection of
the coal from rain and snow may eliminate pollution of
streams with solids and/or dissolved constituents. Figure
3-9 illustrates loading of a unit train from a silo. All
Figure 3-9. Typical unit train loading from a silo (17)
Source: 1974 Keystone Coal Industry Manual
29
-------
storage can be live (active), and availability of coal at
train time does not depend on mechanical equipment, since
only the chutes and gates stand between storage and coal
cars.
Front-end loaders, such as the one shown in Figure 3-
10, are the most versatile of loading equipment. The
machines may be bought for assignment to continuous loading
or be borrowed from other jobs during loading periods. They
can move easily to different coal piles and are practical
for smaller loading operations.
Figure 3-10. Front-end loading on a rail car (17)
Source: 1974 Keystone Coal Industry Manual
30
-------
Unloading --
The unit train concept has made its greatest contribu-
tion in unloading procedures. The idea has led to rotating
car dumpers, illustrated in Figures 3-11 and 3-12, with
swivel couplings that allow the cars to be turned into track
hoppers without uncoupling or breaking an air line. The
hopper allocates the coal onto a conveyor belt, which moves
it toward the power plant storage pile. An older and more
commonly used system for unit train unloading features
bottom discharge hatches, as shown in Figures 3-13 and 3-14,
which are opened and closed either manually or automatically.
Some form of shaker or vibrator is usually required for
complete discharge of the contents.
Freezing and Thawing --
Contrary to some claims, a unit train can freeze rapidly
even on short, fast hauls. Speed does not reduce the likeli-
hood of freezing, since the freezing rate depends upon the
velocity of air over the cars and their cargo. A train
running at 80 km/hr (50 mph) is in effect, exposed to an 80
km/hr (50 mph) wind. Therefore, even at temperatures of -1
to 4°C (30 to 40°F), cars may freeze because of the chilling
effect (8).
When a unit train is subjected to freezing temperatures,
a thawing shed is required to melt the bond between the car
and the frozen coal. A good thawing system will allow
unloading at normal rates. Two modern systems for thawing
are the gas infrared, shown in Figure 3-15, and the electric
infrared. Although both claim advantages, the electric
version may find increasing favor as our gas supplies dwindle.
A coal shaker is also needed where hopper cars are involved,
and in some units a frozen-coal cracker is installed in the
throat of each track hopper.
Barges
In 1973, the Mississippi River System and Gulf Intra-
coastal Waterway carried about 18 percent of U.S. coal
shipments. Total tonnage transported on these waterways
increased 36 percent since 1962. The most heavily traveled
rivers were the Ohio and Monongahela, as shown in Table 3-3.
31
-------
ROTARY CARDUMPER
MAGNETIC SEPARATOR
FEEDER-
-CONVEYOR
Figure 3-11. Illustration of a rotary car coal dumping system (15)
Figure 3-12. Link belt unit-train car dumper (17)
Source: 1974 Keystone Coal Industry Manual
32
-------
Figure 3-13. Unit-train unloading by use of trestle system (17)
Source: 1974 Keystone Coal Industry Manual
Roil Unlooding ^
Hoppers
Figure 3-14. Coal handling combines high-capacity unloading and
ready storage with automated reclaim (17).
33
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Table 3-3. COAL BARGE TRAFFIC ON RIVERS
SERVING THE APPALACHIAN REGION, 1973 (20)
River system
Coal hauled
(1000's net tons)
Mississippi
Ohio
Allegheny
Monongahela
Kanawha
Green & Barren
Cumberland
Tennessee
Warrier & Tombigbee
Total
23,555
65,137
2,351
29,634
7,325
15,458
4,632
11,572
5,509
165,173
Metric conversion: 1 ton = 0.90718 metric ton.
Tonnages of coal on the Great Lakes and Tidewater
Waterways have declined since 1963 by small percentages. In
1973 Great Lakes shipments of coal equaled 35.8 million
metric tons (39-5 million tons) and about 6.6 million metric
tons (7.3 million tons) was moved by tidewater waterways.
Hampton Roads, Virginia, was the primary shipping area (21) .
Of the coal shipped by barge in 1973, over 69 percent
was moved over the Mississippi River and Gulf Intracoastal
Waterway. The remaining 26 percent and 5 percent were moved
over the Great Lakes and tidewaters, respectively.
Most barges today are open-hopper designs with capacities
ranging from 900 to 1800 metric tons (1000 to 2000 tons).
It is expected that the trend will be toward barges in the
range of 900 to 1350 metric tons (1000 to 1500 tons). The
number of barges in tow (10 to 36) is determined by the lock
sizes and also by the capacity of the river. As with unit
trains, most barges return empty when the distance is 800 km
(500 miles) or less (17).
Figure 3-16 shows a 30-barge tow on the Mississippi
River.
34
-------
Figure 3-15. Radac gas-fired Infra-red thawing system in use
at Electric Utility generating station (17).
Source: 1974 Keystone Coal Manual
35
-------
Figure 3-16. 30 Barge tow on the lower Mississippi River (17)
Loading and Unloading —
Generally, coal is transported by train from the mine
to a barge, which transports it to a power plant near the
river bank. Flood loading of barges involves both silo and
ground storage of the coal, usually in higher ranges of
capacity than storage for unit trains, e.g., 12,700 metric
tons (14,000 tons) for a single silo and 68,000 metric tons
(75,000 tons) for a ground-storage facility fed by traveling
stacker. The 1974 Keystone Coal Industry Manual designates
the following five classes for barge-loading plants:
1. A simple dock from which trucks dump into the
barge when water conditions permit.
2. The stationary-chute type, which is simple and
low-priced and works well where the river does not
fluctuate greatly and banks are steep.
3. Elevating-boom type, with barges moved back and
forth in the river beneath. The elevating boom
allows more loading time if river elevation
changes greatly. This type is advantageous where
the bank of the river is a considerable distance
from the channel and the elevating boom and con-
veyor belt can be combined for travel across the
flood plain.
4. Floating-barge type, with the loading boom mounted
on a floating, or spar, barge and pivoted for
easier loading. This method requires a steep bank
or fill to permit retraction and extension of the
main conveyor with changes in water level.
36
-------
5. The tripper-conveyor type, in which the barges are
stationary and the loading chute moves back and
forth to load and trim.
In unloading, clamshell buckets are generally used to
transfer the coal from the barge to a hopper and thence to
conveyor belts and the stockpile.
To speed the turnaround time of river tows, operators
developed continuous bucket unloading systems, as shown in
Figures 3-17 and 3-18. A Dravo Corp. study of various
unloading operations resulted in an excellent high-capacity
unloading system. The system integrates a continuous ladder
unloader, conveyors, and shuttle-barge hauling system,
providing a maximum-efficiency operation (8).
The unloader consists of two continuous bucket ladders
suspended from a twin-girder cantilever, allowing the digging
ladders to be raised and lowered vertically along the fixed
structure. On the first pass, the bucket ladders are posi-
tioned together at the center of the cantilever and dig a
trough through the center of the coal as the barge is being
moved beneath the unloader. During the second pass, the
ladders are spread to the sides of the hopper and dig to the
barge innerbottom, leaving a small area down the center to
be removed on the cleanup pass.
The coal is transferred from the unloader to a dock
conveyor belt, which moves the coal to the main yard con-
veyor belt or to a temporary stockpile nearby.
Conveyor Systems
Conveyor systems are used in all sections of the country
at mines, power plants, bargeloading stations, and industrial
sites. They are most often found within a processing area,
moving crushed coal 30 or 60 meters (100 or 200 feet) to a
storage area, a cleaning station, or a loading station.
Popularity of longer belt systems is growing. Belts
running up to 16 km (10 miles) from the active mine directly
to the consumer are more common than a few years ago, and
plans are being studied for belt systems as long as 240 km
(150 miles) .
A conveyor system is versatile, easy to operate,
generally reliable, relatively maintenance-free, and repairs
can be done quickly. Though the systems are usually fixed
37
-------
Figure 3-17. Barge-unloader elevator carriage showing transverse and
longitudinal drives for scopping patterns (17).
Source: 1974 Keystone Coal Industry Manual
Figure 3-18.
Continuous-bucket elevator transferring coal to conveyor
system for outside live storage (17).
Source: 1974 Keystone Coal Industry Manual
38
-------
some surface mines are using shiftable conveyor systems that
can follow the coal digging equipment.
One advantage of an overland conveyor is that it can be
built over difficult terrain with minimum costs for earth-
work. A conveyor system is feasible in some areas where
construction of a road or railbed with an acceptable grade
could cause controversy on environmental grounds. Figure
3-19 shows a portion of the Kayenta mine conveyor belt in
Kayenta, Arizona.
Figure 3-19. A portion of the I¥ta mine conveyor belt
in Arizona.
39
-------
Before it is moved on a conveyor belt, coal is reduced
to a specific size by crushers. Short conveyors generally
move the coal to a storage facility or feed it directly to
the next conveyor stage. If the coal is placed in open
storage, a reclaim conveyor, fed by a traveling rotary plow
feeder, transfers the coal to the main overland conveyor.
All coal is weighed on a belt scale before traveling to its
loadout point.
Major capital and operating costs of an overland system
are the conveyor components and supports, which include
idlers, structures, foundations, belting, and drives.
Requirements for all of these components are influenced by
the width of the system, which varies directly with the
speed of the belt. On the longer systems heavy-duty idlers
are used to allow greater spacing between them. On the 16-
km (10-mile) conveyor belt feeding the Gavin Plant in Ohio,
the spacing between idlers is double that of conventional
systems, with 305-cm (10-ft) spacing on the troughers and
610-cm (20-ft) spacing on the return (21).
Belt wear is principally at transfer points because of
impact and acceleration forces. Thus minimizing the trans-
fer points is desirable for economical as well as environ-
mental reasons.
Trucks
Trucks comprise a very minor part of the long-haul
market. They are used mainly for initial or final shipment
over short distances. The relatively low capital investment
for trucks and their greater flexibility are the major
reasons that smaller mine operators use them. In addition,
many of the small operators move their coal through a
tipple operated by someone else, where the coal is loaded
for movement by rail or water. Table 3-4 lists truck ship-
ments of bituminous coal in 1973.
Since the railroads generally expect mine operators to
finance spur lines into the mine site, the large cost of
building the spur must be justified by high-volume, long-
term production. A small mine operator, who moves relatively
often, cannot justify this large expenditure. The increas-
ing number of strip mines, the increasing cost of rail
trackage, the shortage of coal cars, and the availability of
public roads influence more and more coal operators to use
trucks (22). Often, the trucking is done by a private
40
-------
Table 3-4. TRUCK SHIPMENT OF BITUMINOUS COAL,
BY STATE, 1973 (18)
(thousands of net tons)
Alabama and Mississippi
Alaska
Arkansas, Louisiana, Oklahoma, and Texas
Colorado
Delaware and Maryland
Georgia
Illinois
Indiana
Iowa
Kansas
Kentucky
Missouri
Montana and Idaho
New Mexico
New York
North Carolina
North and South Dakota
Ohio
Pennsylvania
Tennessee
Utah
Virginia
Washington and Oregon
West Virginia
Wyoming
Origin-destinations not revealable
Total United States (c)
Total destinations via truck
Shipments
originated
3,003
115
142
746
553
3,393
3,682
439
74
6,094
90
28
3
11,555
17,824
2,618
1,492
1,285
24
3,776
45
57,268
Shipments
received
4,847 (a)
(b)
244
1,259
689
5,540 (a)
5,847
459
9,979
3,304 (a)
80
7,330
1,330
14
2,887 (a)
15,836 (a)
20,618
2,376
1,355
106
30
3,181 (a-)
5,670
223
93,004 (a)
68,114
b
a Includes shipments by tramway, conveyor, and private railroad,
as noted.
Included with all rail shipments.
Data may not add to totals shown because of independent rounding,
Metric conversion: 1 ton = 0.90718 metric ton.
41
-------
individual or group under contract with the coal operator,
who may find it economical to hire an outside trucker and
concentrate on his mining operations.
Trucking came to be the major mode for short-haul
transportation during the 1960's and early 1970's, largely
because of the following factors:
1. Railroads offer no flexibility as old mines are
closed and new mines are opened.
2. The efficiency and carrying capacity of trucks have
increased.
3. National emphasis has been placed on building a
superior highway network.
4. Other modes of transport are often unavailable.
Of all modes of transport, trucking is the most costly.
Transportation under 240 km (150 miles) costs an average of
$0.04 per metric ton-km ($0.06 per ton-mile). The cost
curve for truck transport, shown in Figure 3-20, declines
quickly with distance, but little increase in savings can be
realized beyond distances of 322 km (200 miles) (22).
o
I—
ai
o
o
7.0
6.0
5.0
4.0
TOO
DISTANCE, MILES
400
200 300
1 mile = 1.609 km
Figure 3-20. Cost of transporting coal by truck (22)
42
-------
Most of the coal-hauling trucks on the highways are in
the range of 18 to 27 metric tons (20 to 30 tons) capacity
and travel about 8 km (5 miles) per gallon of fuel on the
average. Trucks used for short, off-the-road hauls near or
on mine sites are of various sizes, some as large as 154
metric tons (170 tons). Figure 3-21 illustrates a typical
truck used for on-site mine coal hauls.
Figure 3-21. Typical truck used on-site at a coal mine,
Pneumatic Pipelines
A pneumatic pipeline represents relatively new tech-
nology for transporting coal. Basically, it is a pressur-
ized pipeline into which granular coal is fed and conveyed
in a suspended state by air pressure. Two major factors
influence the economic feasibility: capital and operating
costs of air compression equipment, and haulage capabili-
ties. These factors in turn vary with characteristics of
the pneumatic system: the diameter, length, and configura-
tion of the pipe; and the size, size distribution, moisture
content, and ash content of the coal (23).
Currently, the most feasible application of pneumatic
pipelines appears to be movement of coal to and from a rail
terminal, possibly allowing the railroad operators to
43
-------
abandon unprofitable spur lines and thus release money for
upgrading their main lines.
Pneumatic pipelines could be particularly advantageous
in the West because they require no water. An above-ground
pneumatic system requires minimal ground prepartion, and it
is almost portable if relocation is needed (24). Also,
because gravity is not a large factor in pressure drop, a
pneumatic pipeline can cover the steepest terrain by the
most direct route.
Basically, a pneumatic pipeline system consists of a
pump to supply air pressure, silos for storing the coal to
be fed into the pipeline, and a cyclone and baghouse to
remove it at the end. The optimal air pressure appears to
be 10 atmospheres at a mass flow ratio (coal-to-air) of
nearly 1 to 10 (23). Diameter of the pipe increases (tele-
scoping) to accommodate the decrease in density (or increase
in volume) as the pressure decreases along the pipeline. If
a power failure occurs, the line must be temporarily closed
down but the shutdown will not cause plugging of the pipes
(23). At the terminal end a cyclone removes particles
larger than 5 microns diameter at efficiencies of about 98
percent (23) . The 'remaining particles may be removed in a
baghouse. Estimated total operational cost is 1.4£/metric
ton-km (2£/ton-mi)•
Ozone, Inc., a Colorado company, has operated a pneumatic
system with 10- and 15-cm (4- and 6-inch)-diameter pipes
over a distance of 102 m (4000 ft). They are proposing a
34-km (21-mile) line from a mine in Carbondale to a coal
spur. The line would operate at 10 atmospheres, trans-
mitting 5440 metric tpd (6,000 tpd) of coal through a 36-cm
(14-inch)-diameter pipe. The power requirement of approxi-
mately 3730 kW (5000 hp) would be supplied by one pump (23).
Very few tests have been condxicted to determine optimal
design. More studies must be made and test results analyzed
before the extent of pneumatic pipeline utilization can be
determined. To date such systems look very promising for
short-distance transport to complement railroads and other
modes of transportation. The potential for long-distance
interstate pneumatic pipelines will be known only when tests
are completed.
44
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1985 PROJECTIONS FOR COAL PRODUCTION AND TRANSPORT MODES
Coal Production and Movement.
It has been estimated that coal production will in-
crease from the 1975 level of 581 million metric tons (640
million tons) to 1.09 billion metric tons (1.2 billion tons)
in 1985 (24). Figure 3-22 shows 1975 and projected 1985
coal production by districts.
The origin and movement of coal, illustrated in Figure
3-23 A and B for 1975, is not expected to change dramatically
but the flow of western coal to the east will undoubtedly
increase as more mines are developed. These shipments will
require substantially more energy per unit delivered than
does transport from the interior region or Appalachia and
thus will cause a significant increase in transport costs.
These costs currently range from approximately 25 percent of
the cost of the coal delivered from eastern coal fields to
as much as 75 percent or more of the delivered price of
coals shipped from Montana and Wyoming to electric utilities
in the midwest.
1985 Projections for Coal Transport Modes
Approximately 67 percent of the bituminous coal and
lignite production was shipped by rail in 1975. The inland
waterway system, trucks, and mine mouth plants (tramway,
conveyor, private rail) each accounted for about 11 percent
of coal traffic. In addition, 3.8 million tons (0.6% of
total) of coal was transported through the Black Mesa coal
slurry pipeline. Table 3-5 presents a breakdown of coal
transport by mode for 1975 and projections for 1985 (21).
SUMMARY OF COAL TRANSPORTATION COSTS
Table 3-6 summarizes the costs of coal transportation
as derived from various published sources. The costs are
presented in cents/metric ton-km (cents/ton-mile); they are
based on hauling 22.7 million metric tons (25 million tons)
of coal per year over a distance of 1610 km (1000 miles)
except as indicated. The most controversial major studies
are by the University of Illinois and Bechtel/ETSI which
differ regarding costs of unit train and slurry pipeline
transport of coal. The ETSI, "Chemical Engineering", and
45
-------
a\
0
ANTHRACITE, SEMI ANTHRACITE S
META ANTHRACITE
LOU VOLATILE BITUMINOUS
MEDIUM S HIGH VOLATILE BITUMINOUS
! MEDIUM S HIGH VOLATILE BITUMINOUS
: (DOUBTFUL PRESENT VALUE)
I SUB BITUMINOUS
1 SUB BITUMINOUS
i (DOUBTFUL PRESENT VALUE)
[ LIGNITE 8 BROWN COAL
{ LIGNITE 4 BROWN rnfll
j (OOUBTFUL PRESENT VALUE)
. PRODUCING DISTRICTS
PER BITUMINOUS
COAL ACT OF 1937
COAL MOVED PER YEAR
> .5-1.5 MILLION TONS
x.
6 > # INDICATES MILLIONS OF TONS
Figure 3-23A. Origin and movement of coal - 1975 (26, 27).
-------
Centr
ct>ehalis f
OlO
pnnqs
a Canon Of y
COLO
^.Trinidad
•Brood
Susitna ^ .-Motonu
Figure 3-23B. Origin and movement of coal - 1975 (26,27)
47
-------
Table 3-5. ESTIMATES OF U.S. COAL TRANSPORT BY MODE
FOR 1975 AND 1985
Mode
Rail
Barge
Truck
Pipeline
Miscellaneous
Totals
1975
MM tons
428
73
70
4
65
640
%
66.8
11.4
11.0
0.6
10.2
100
1985a
MM tons
726
192
132
5
145
1200
%
60.5
16
11
0.4
12.1
100
Based on data from Bureau of Mines, 1985, projection, for
their unconstrained mode (21, 25).
Includes coal consumed at mine mouth: tramway, conveyor, and
private rail; and overseas exports.
Metric conversion: 1 ton = 0.90718 metric ton.
48
-------
Table 3-6. SUMMARY OF COST OF TRANSPORTING 75 MILLION TONS OF COAL
PER YEAR A DISTANCE OF 1000 MILES
(except as indicated)
Source
Univ. of Illinois3
ETSIb
Becntel0
Ebasco
Chem. Engineering
Oil & Gas Journal
Elec. Lgt. £, Powerg
Upper Midwest
Council0
Costs, cents per ton-mile
Rail
0.31
0.80
0.70
1.00(2.88)
0.4-0.9
0. 6
0. 5-0.9
0.71
Slurry
0.69
0.51
0.39
0.62(1.78)
0.3-0.7
0.36
1.08
Barge
0.34
0.45
0.3-0.5
(inland
waterways)
Rail/Barge
0.80(2.30)
Truck
Conveyor
5.0-8.0 2.0-6.0
1975 costs; 7% annual escalation rate for both rail and slurry; rail costs assume new rail
50-60 mph; slurry costs are for a new system.
1975 costs; new slurry line, existing rail facilities, includes purchase of hopper cars.
C 1975 costs for a 1978 installation date; assumes an annual escalation rate of 7% for rail
and 4% for slurry pipelines. Rail = 147.04 (Distance) -0.418 Barge distance = 600 mi.
(70.93 (Distance)--285).
Mid 1975 costs; Barges - 600 mi. distance, pipeline, all rail and rail/barge 900 miles; numbers
in parentheses are costs based on 1980 starting date.
e 1971 costs; slurry, over 50 miles, unit train, over 400 miles, truck, no mileage given, conveyor
belt, less than 15 miles.
f 1973 costs.
9 1973 costs.
1976 costs for transportation of 12 million tons per year of coal over a distance of 700 miles.
Metric conversion: 1 ton = 0.90718 metric ton
1 mile = 1.609 kilometer
-------
"Oil and Gas Journal" sources were prepared by ETSI members
at different times.
On the basis of these data, it is difficult to compare
precisely the costs of transporting coal in a wide range of
volumes and regularity of shipments to an even wider variety
of destinations. The studies clearly indicate, however,
that long-distance pipeline and rail shipments of coal are
both feasible in a comparative cost sense. Therefore, both
are viable possibilities, especially for shipment of western
coal, where new mines will typically support large-volume
movements. Although about 15 percent of coal tonnage moves
on inland and coastal waterways, this traffic is limited to
that originating from mines adjacent to existing waterways
or coal shipped to waterways from distant mines. The cost
of water shipment is typically lower than costs for the same
service by rail (21).
In a choice between pipelines and railroads, neither
seems to be superior to the other in a general evaluation.
In specific cases, however, one mode might be preferred,
though likely by a narrow margin. In any proposed cost
analysis, therefore, the circumstances should be reviewed in
light of the best current information.
Should the Bechtel/ETSI rationale prove to be realis-
tic, use of pipelines can be expected for very large ship-
ments, with the railroads continuing to dominate the field
for transport of large but not huge volumes of coal.
On the other hand, if the University of Illinois ration-
ale proves to be realistic, operation of slurry lines would
be expected only where no rail facilities are available. If
the railroads can handle the expected increase in coal
production, they would have a definite cost advantage over
the slurry lines, even if the existing rail lines had to be
considerably upgraded.
ENERGY REQUIREMENTS FOR COAL TRANSPORTATION
Data are available from a number of sources on energy
requirements for transporting coal by various methods.
Table 3-7 summarizes these data, which show a wide range of
energy requirements depending on the source and whether the
estimate includes the entire transport system.
50
-------
Table 3-7. ENERGY REQUIREMENTS OF VARIOUS COAL TRANSPORT MODES
FROM PUBLISHED SOURCES
Transport
method
Pipeline
Railroad
Barge
Truck
g-cal
metric ton-km
51,000
170,000
310,680
43,000
129,000
86,300
870,000
964,000
414,000
Btu/lb
295
980
1800
250
750
500
5040
5583
2400
Source
Energy Transport Systems, Inc. (24)
Upper Midwest Council3
Rand Report (30)
American Association of Railroads (24)
Rand Report (30)
American Waterways Operators (30)
Zandi and Kim (24)
Zandi and Kim (24)
Rand Report (30)
Murphy, Michael V. Northern Great Plains Coal:
Conflicts and Options in Decision Making.
Upper Midwest Council. April 1976.
-------
This section presents PEDCo's estimates of the energy
required to transport coal by rail (unit train), slurry
line, barge, truck, and conveyor belt. Rail and slurry line
transport are the most important, since they are the most
likely to affect the future of coal transportation. These
comparisons are based on energy requirements for processes
in each system in addition to the transportation portion.
Data on the 440-km (273-mile) Black Mesa pipeline (1975) are
used as a base, and energy requirements of unit trains and
barges are adjusted to reflect a 440-km (273-mile) trip.
Trucks and conveyors are assumed to travel short distances
[8 to 32 km (5 to 20 miles)]. Energy requirements are
presented in g-cal/kg (Btu/lb) and g-cal/metric ton-km
(Btu/ton-mile). The g-cal/kg (Btu/lb) unit shows how much
of the energy in a kg (Ib) of coal is needed for various
operations.
Slurry Pipeline --
Calculation of energy requirements for the Black Mesa
line includes power consumption for slurry preparation,
transportation, dewatering (including heating of the slurry),
gas consumption to dry the slurry in the primary air ducts,
and reduction in heating value of the coal finally fired due
to the additional water it contains (heat of vaporization,
sensible heat loss). A flue gas temperature of 280°F is
assumed. Table 3-8 summarizes the estimated energy consump-
tion of the Black Mesa pipeline.
Unit Trains --
Computations of energy requirements for unit trains are
based in part on data from the Hittman Report (28). Included
are the heating value loss due to diesel oil consumption;
fugitive dust emissions (assumed to be 0.09%) in loading,
unloading, and transit; and power consumption for crushing
at the power plant. Heat of vaporization and sensible heat
loss are included in 10,858 Btu/lb heating value used as a
reference.
Table 3-9 summarizes energy requirements of a unit
train, based on the same conditions used in the Black Mesa
pipeline calculation. The two are not directly comparable
since the Black Mesa line was built because the terrain was
too difficult for trains; with terrain suitable to unit
trains, however, the two would be comparable, although the
rail distance required would probably be greater than that
for the pipeline.
52
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Table 3-8. SUMMARY OF ESTIMATED ENERGY REQUIREMENTS,
BLACK MESA COAL SLURRY PIPELINE (1975 DATA)
Source of energy loss
Power consumption
(slurry preparation,
pumping, dewatering)
Gas consumption
(required to dry incoming
coal cake to furnace to
prevent coal "plastering"
Heat loss
(slurry heating with steam
to 140°F, to increase
efficiency of centrifuges
and pulverizers)
Coal quality loss
(due to 29% combined
moisture content of
coal cake and under-
flow, includes latent
heat of vaporization ,
plus sensible heat loss)
Total
Btu/lb
78
130
107
2,467
2,782°
Btu/ ton-mile
576
950
782
18,035
20,343
% of energy
transported
0.72
1.2
0.98
22.7
25.6
a 1.03 x 10 ton-mi in 1975 based on 3,765,000 contract tons
shipped a distance of 440 km (273 miles).
Assumes a flue gas temperature of 280°F.
Q
Additional energy required to generate electricity to run
pipeline not included (approx. 156 Btu/lb).
Metric conversion: 1 Btu/lb = 114.3 g-cal/kg
1 Btu/ton-mi = 172.6 g-cal/metric ton-km
53
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Table 3-9. SUMMARY OF ESTIMATED ENERGY REQUIREMENTS
FOR 273 MILE UNIT TRAIN HAUL OF 3,765,000 TONS
OF COAL ANNUALLY
Source of energy loss
HV loss due to fuel oil
consumption3
HV loss due to fugitive
emissions , loading,
unloading in transit
HV loss due to crushing
at power plant0
Totals
Btu/lb
95
10
30
135
Btu/ ton-mile
694
71
219
984
% of energy
transported
0.87
0.09
0.28
1.24
(28)
Fuel consumption = (0.005 gal/ton-mi)(1.03xl09 ton-mi/yr)
= (5.15xl06 gal./yr) (138,800 Btu/gal.)
11,
= 7.15xl011Btu/hr
= 694 Btu/ton-mi
Assumed to be 0.09%.
c
(29)
Metric conversion: 1 Btu/lb = 114.3 g-cal/kg.
1 Btu/ton-mi = 172.6 g-cal/metric ton-km
54
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Table 3-10. SUMMARY OF ESTIMATED ENERGY REQUIREMENTS FOR
273-MILE BARGE HAUL OF 3,765,000 TONS OF COAL ANNUALLY
Source of Energy loss
HV loss due to fuel oil
consumption
HV loss due to crushing
at power plant
HV loss due to fugitive
dust emissions0
Totals
Btu/lb
68
30
7
105
Btu/ton-mi
500a
219
48
767
% of energy
transported
0.63
0.28
0.06
0.97
a
b(30)
(29)
c
Assumed to be 0.06%
Metric conversion 1 Btu/lb = 114.3 g-cal/kg.
1 Btu/ton mi = 172.6 g-cal/metric ton km.
55
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Table 3-11. SUMMARY OF ESTIMATED ENERGY REQUIREMENTS
FOR TRUCK TRANSPORT OF COAL
(30-TON PAYLOAD, 20 MI. ONE WAY)3
Source of energy loss
HV loss, fuel oil consumption
HV loss, crushing at powerc
plant
HV loss, fugitive emissions
from loading, unloading, in
transit
Totals
Btu/lb
22
30
10
62
Btu/ ton-mile
2,150
3,000
1,000
6,150
% of energy
transported
0.20
0.28
0.09
0.57
Coal as received at mine = 10,858 Btu/lb.
Fuel use =
.-4
. *"" ft i
d
1.62 x 10 gal/lb trip
Energy required - (1.62 x 10""*) (6.8 Ib/gal) (19,800 Btu/lb)
22 Btu/lb.
(29).
Loading plus unloading = 0.04%; in transit = 0.05%.
Metric conversion: 1 Btu/lb = 114.3 g-cal/kg.
1 Btu/ton-mile = 172.6 g-cal/metric ton-km,
56
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Table 3-12. SUMMARY OF ESTIMATED ENERGY REQUIREMENTS
FOR CONVEYOR TRANSPORT OF COAL
(10 MILES, 3 TRANSFER STATIONS)3
Source of energy loss
HV loss, power consumption
HV loss, crushing at power
plant
HV loss, fugitive emissions
at transfer points (3) and
in transit
Totals
Btu/lb
4
30
7
41
Btu/ ton-mile
800
6,000
1,400
8,200
% of energy
transported
0.04
0.28
0.06
0.36
Coal as received at mine = 10,858 Btu/lb.
b (31).
° (29).
Transfer points = 0.04 percent; in transit = 0.02%.
Metric conversion: 1 Btu/lb - 114.3 g-cal/kg.
1 Btu/ton-mile = 172.6 g-cal/metric ton-km
57
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Table 3-13. ESTIMATED ENERGY REQUIREMENTS OF
VARIOUS COAL TRANSPORTATION SYSTEMS
Mode
Slurry linea'b
Unit train
Bargea
Truck0
Conveyor
Btu/lb
315 (2782)
135
105
62
41
Btu/ ton-mile
2308 (20,343)
984
767
6150
8200
% of total
Btu transported
2.9 (24.4)
1.24
0.97
0.57
0.36
Based on 273-mile trip; 3,765,000 tons coal per year;
10,858 Btu/lb as received at the mine.
Numbers in parentheses include heat loss because of
additional water content of fired coal.
Twenty-mile one-way trip, 30-ton payload.
d
Based on telephone conversation with personnel at
American Electric Power for the Meigs Mine Conveyor;
10-mile trip, 2000 tons/hr.
Metric conversion: 1 Btu/lb = 114.2 g-cal/kg.
1 Btu/ton-mile = 172.6 g-cal/metric ton-km
58
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SECTION 4
ENVIRONMENTAL IMPACTS ASSOCIATED WITH COAL TRANSPORTATION
IMPACTS FROM COAL PREPARATION AND ASSOCIATED ACTIVITIES
By whatever means coal is transported, some type of
preparation always precedes shipping. Preparation can
consist of (1) complete preparation - cleaning both coarse
and fine coal, (2) partial preparation - cleaning only
coarse coal, and (3) simple crushing of the coal to a specific
size (32). This section describes the environmental impacts
of coal preparation 'and the associated activities that occur
before the coal is transported.
Coal Cleaning Operations
Pulsating air columns and thermal dryers are the major
sources of airborne emissions from coal cleaning operations.
Pulsating air columns (dry process method) release approxi-
mately 1.4 kg (3 pounds) of particulates per metric ton
(ton) of coal. Thermal dryers release both particulates and
combustion products. Coal is the primary fuel used to
produce the hot gases that evaporate moisture from the
product; fuel oil is used at some installations, especially
during startup.
Dust loading of the effluent from a dryer operating at
65°C (150°F) with throughput of 0.085 to 56.6 m3/sec (180 to
120,000 cfm) of 0.64-cm (1/4-inch) centrifugal coal and
filter coke can exceed 5.7 g/m3 (2.5 gr/ft3), with the
following particle size distribution (23):
0 to 2 micron 55% by weight
2 to 5 33
5 to 10 11
10+ 1
Primary dust collectors are cyclones followed by wet
collectors and demisters. Conventional scrubbers have not
59
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proved effective on thermal dryers, but high-energy venturi
scrubbers with demisters have reduced the grain loading in
several installations from a high of 2.3 g/Nm3 to 0.017
g/Nm3 (5.5 scf to 0.04 scf) (33).
Refuse piles are a constant source of combustion and
dust-related air pollution. Emissions from the piles, in
addition to blowing dust are I^S, S02, and .smoke. Other
noxious gases released from burning piles include CO,
ammonia, and carbon disulfide.
Contaminants in the process water from wet coal clean-
ing consist of suspended solids, which are chiefly fine clay
and coal, and dissolved solids, which may contain iron,
aluminum, calcium, magnesium, sodium, and potassium. Water
effluents may also contain surface active organic compounds
such as alcohols or kerosene, which are added in some coal
cleaning plants to enhance frothing. Water contaminants in
refuse pile runoff include sulfuric acid, sulfates, manganese,
and iron, aluminum, and other heavy metals.
Open Coal Storage --
Stockpiles have been used widely at mine preparation
plants and loading stations since the advent of the unit
train. The intent is to store enough coal to load one unit
train, usually 3630 to 9070 metric tons (4000 to 10,000
tons). Some of the stockpiles are designed to contain
several days' production or up to five unit trains capacity
(45,360 metric tons or 50,000 tons). At power plants the
coal storage piles may contain a 60-day supply.
The two primary forms of air pollution from open coal
storage piles are blowing dust and combustion products.
Escape of fugitive dust is discernible, but the rate is
unknown and variable. If the pile is in constant use, no
stability is achieved, and effective chemical treatment is
difficult.
Several activities cause fugitive dust emissions from
the storage area (34). Midwest Research Institute (MRI)
evaluates the four major emissions-producing activities in
crushed-rock storage and their approximate relative contribu-
tions are as follows: (35)
Loading onto piles 12%
Equipment and vehicle 40%
movement in storage area
60
-------
Wind erosion
Loadout from piles
33%
15%
Although such percentages may vary with storage of different
materials and with specific storage area configurations, the
same activities constitute the major dust sources in all
types of open storage.
In an earlier EPA study the Monsanto Research Corpora-
tion measured dust losses from a coal storage pile during
two sampling periods. The coal pile produced emissions at
rates of 0.0045 and 0.008 kg/metric ton (0.009 and 0.016
Ib/ton). By use of additional information on the storage
throughput rate (36), these values were converted to an
annual emission rate of 0.027 kg/metric ton (0.054 Ib/ton)
placed in storage. No loading or unloading took place in
the storage area during either sampling period.
Methods for control of dust from coal storage piles are
limited in effect or are very expensive. As a minimum the
piles should be capped with larger-size coals to prevent
loss of fines due to wind. Bituminous coal should be packed
and sealed to prevent fires. Some installations use con-
crete silos, which hold up to 9070 metric tons (10,000 tons)
tons each and control dust effectively. An earthen impound-
ment also can contain and control the coal mass, as shown in
Figure 4-1. This method also reduces dead space to a mini-
mum, but is not entirely effective in controlling dust.
COAL
EARTH
Figure 4-1. Earthern impoundment for control of dust from
coal storage piles.
61
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Unloading Bins —
Bins into which trucks dump coal, with feeders under-
neath to transfer coal to a conveyor, are very common. Dust
can escape where the trucks dump at the top and where the
feeders empty the coal at the bottom. The escape is sub-
stantial if the coal is dry and fine and if wind speed is
high. Emissions are controlled at the bottom with sprays or
a dust collector with bags or a scrubber. Enclosure of the
top of the bin on three sides and with a sloping roof will
contain the dust in most cases. If supplemental control is
required, curtains can be hung to partially close the opening
while a truck is dumping. A dust collector can then be used
with some effectiveness.
In two other separate studies, PEDCo used a dust emission
value of 0.01 kg/metric ton (0.02 Ib/ton) for truck dumping,
based on a 50 percent reduction in dust due to watering
(35) .
Sprays do not function well at bin-loading operations
because the area is so large and the dust surge is violent
and intermittent.
Crushers --
A crusher house usually contains vibrating screens to
remove the undersize coal for bypass and a hammermill to
reduce the large coal to specified size. Crushers may
operate at the mine, the preparation plant, or the power
plant. Crushers are used universally in all sections of the
country, sometimes combined with a cleaning plant.
Crusher installations are extremely dusty and noisy and
if not enclosed would lose 1 or 2 percent of the coal to the
air, depending on wind velocity and the coal being crushed.
Soft coal (typically Pocahontas No. 3) with a low moisture
content would create the most dust, and Western subbituminous
coal of 25 to 30 percent moisture would create the least.
The crusher is normally enclosed, but dust control
equipment is not always provided. The basis for positive
control is some combination of dry and wet cyclones, washdown
equipment, and sprays. Baghouses are also suitable.
62
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Loading Stations —
A loading station is a structure for loading a unit
train at a rate up to 5440 metric tph (6000 tph) (one 100-
ton car per minute). The station consists of a surge bin
above the track large enough to hold incoming coal while
cars are changing, a loadout chute, and a control room.
Another type of loading station involves a 9070-metric-ton
(10,000-ton) silo, under which the unit train moves for
loading. These stations, or similar ones, are located
everywhere unit trains are loaded (see Figure 4-2).
Figure 4-2. Loading station for unit train.
Use of a loadout chute can prevent an enormous amount
of dust and spillage when coal is transferred to cars in
such high volumes. The chute is a large, vertical telescopic
device that travels to the car bottom with each new car,
raises with the coal as the car is filled, stops and crowns
the car, stops the flow of coal as cars ar= changed, and
repeats the cycle. During loadings, the cnute remains in
contact with the coal in the car and thus prevents the
escape of dust and spillage. Water sprays are not commonly
An uncontrolled emission value of 0.2 kg/metric ton
(0.4 Ib/ton) is used in Section 4 of this report for applica
tion to loading or unloading activities in all modes of
transport; this value is based on information developed by
Hittman Associates (37) .
63
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Emissions Estimate - Coal Preparation And Associated
Activities --
Table 4-1 summarizes atmospheric emissions from a
preparation plant that processes 5720 metric tons (6300
tons) per day of run-of-the-mine (ROM) coal (38).
Energy and Water Requirements - Coal Preparation and Associated
Activities --
Energy required for coal cleaning plants is supplied as
electrical energy and diesel oil. Electricity, the main
energy source, is consumed at the rate of 3.4 kWh/metric ton
(3.7 kWh per ton) of coal cleaned (38). Electricity can be
generated by in-plant process boilers or it can be delivered
by transmission lines. Availability of transmission lines
can be a problem for remotely situated plants.
A coal preparation plant producing 9100 metric tons
(10,000 tons) of cleaned coal per day needs about 2,2
million liters (580,000 gallons) per day of makeup water for
wet cleaning operations (38). Water supply for such purposes
may be a problem in the siting of large coal preparation
plants, especially in arid sections of the nation.
IMPACTS FROM COAL SLURRY PIPELINES
Among the modes of coal transport in this study, pipe-
lines transport the smallest volumes. The only pipeline now
operating is the Black Mesa Pipeline, which began commercial
operation in 1971.
The environmental impacts from pipelines are considered
in relation to the periods of construction, operation, and
abandonment of the system.
Construction of Pipeline
The terrestrial environment is likely to be the most
affected by construction of a slurry pipeline. Construction
of a 61-cm (24-inch)-diameter pipeline requires up to 25,150
m^/km (10 acres/mile) of land; two pipelines sharing a _->
common right-of-way would require approximately 30,200 m /km
(12 acres per mile). The right-of-way would preempt any
development. In most areas, this would be an unimportant
effect.
64
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Table 4-1. ATMOSPHERIC EMISSIONS FROM COAL PREPARATION
AND ASSOCIATED ACTIVITIES3
Basis: 6300 ton/day ROM coal
Source
Primary crushing t>
Loading and unloading
at the Preparation
Plantb
Thermal drying0
Vehicle emissions
from refuse hauling
operations
Total
Emissions Ib/day
Parti-
culates
125
50
7
0.9
83
so2
1292
1.8
1294
CO
34
15
49
Hydro-
carbons
17
2.9
20
NO
X
612
25
638
a Based on data from (38).
b 80 percent particulate control by water spraying and dust
control techniques.
c 99 percent particulate control by negative pressure apparatus
plus wet scrubbers.
Metric conversion: one pound = .4536 kg
one ton - .90718 metric ton
65
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Removal of vegetation and trenching cause various
impacts on the environment. During construction all cover
vegetation is likely to be removed and destroyed. Removal
of the vegetation destroys wildlife habitat, which may not
recover for a long period of time. Wetlands are particularly
susceptible to such disturbance because of their high pro-
ductivity and their intolerance to environmental upset.
Removal of cover vegetation also brings about the
potential of erosion by water and/or wind. Microclimatic
changes may occur along the right-of-way as removal of
vegetation alters the humidity levels, surface temperatures,
and wind fields. These changes also can affect the types of
wildlife that inhabit the area.
Traffic by trucks and construction equipment hauling
and stringing the pipe will cause emissions of fugitive
dust. This increase in human activity in remote areas may
adversely affect fauna that are intolerant of human beings
and the disturbances they bring. Accidental spills of
materials used in pipe coating may contaminate soils and
hinder revegetation.
Further, fauna can die from ingestion of small foreign
objects such as nuts, bolts, and metal shavings. Therefore,
the area must be thoroughly monitored and cleaned when
construction ends.
A pipeline may cross moving bodies of water at various
points. Usually the pipe is placed in a trench in the river
bottom and buried, rather than laid on a support bridge over
the river. This phase of construction causes serious
disruption of aquatic life. Benthic organisms would be
severely disturbed at the site where the pipe is laid and
high levels of suspended solids resulting from bottom
disturbance can damage aquatic life downstream. At the same
time, runoff of sediment from construction near the stream,
if not properly controlled, will adversely affect aquatic
life. Among the detrimental effects are clogging of fish
gills, covering of benthic organisms and eggs, and reduction
of photosynthetic capabilities because of increased turbidity.
All of these impacts in the construction phase can be
prevented or greatly limited if proper precautions are
taken. Removing as little vegetation as possible, keeping
noise and vehicle movement to a minimum, policing the
construction area, and promptly implementing revegetation
66
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programs will aid in preserving the environment.
Operation of Pipeline
Coal Enroute --
No air emissions are directly attributed to the transfer
of coal by slurry pipeline under normal operating conditions.
The pump stations, located 100 to 160 km (60 to 100 miles)
apart, are electrically powered. Noise from the pump stations
is not considered an offsite problem since these stations
are usually located in remote areas and the buildings in
which the pumps are housed provide a shield to reduce the
noise.
Because availability of water in the western States is
relatively low, the matter of water usage raises the most
controversy concerning possible operational impacts of
slurry pipelines. The exact impacts of water withdrawals
for a slurry pipeline have not been determined. Each case
must be evaluated in relation to the local conditions.
Water used to slurry the coal will be pumped from local
water supplies, and at present it is uneconomical to return
it. Thus the local area will benefit only indirectly from
use of the water, i.e., from any economic benefits of the
pipeline. If the water supply is plentiful, then impact
from water usage would be minimal. Appendix A discusses in
greater detail the availability of water in the semiarid
western states.
Another concern is the possibility of an accidental
release of slurry by a pipeline break or pump station
malfunction. The slurry could cause damage to agricultural
crops and/or local vegetation, and the runoff could adversely
affect nearby water bodies. Since pump stations are designed
with holding ponds for use in case of malfunction, the major
impacts would occur only in the case of a pipeline break.
A pipeline break could cause fine particles of coal to
be spread over the surface of the soil and to be mixed with
it. The surface particles may also prevent absorption of
water into the soil. Additionally, the fine particles may
be a source of fugitive dust.
Use of saline water in the slurry involves an additional
environmental hazard. Under normal circumstances, one may
assume that slurry would be discharged from any uphill
sections of the pipe on either side of a break. In the
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worst case, a break would occur in a valley between two high
ridges. Assuming a 96-cm (38-inch) pipeline, 100 km (60
miles) of pipe between ridges, a slurry of 50 percent solids,
an average water depth of 15 cm (6 inches) over flat terrain,
a pipeline break would inundate a total area of about 220,000
m2 (50 acres), leaving about 388 grams/m2 (36 grams/sg ft)
of salt from transport water having saline content of 5000
mg/liter (9). Flooding of alkali soils in arid areas with
this amount of sodium salts, even in a one-time release,
could considerably worsen their suitability for vegetation.
In good soils, however, absorption of salts would have
little effect, and all effects would disappear with rain-
fall. A one-time spill of this quantity of saline water
(about 4.16 million liters or 1.1 million gallons) into a
local aquifer would be of little lasting consequence as a
result of dilution. In some areas crops are irrigated with
water containing up to 3000 mg/liter of total dissolved
solids. The effect of discharge into a watercourse would be
totally dependent on the stream-flow at the time. The added
impact of saline water is greater in a watercourse than that
of a fresh water slurry, since the salt effects extend over
much longer reaches of the stream than the effects of coal
fines.
The potential rupture of a coal slurry pipeline is an
unsolved environmental problem, although the technology for
monitoring breaks is sophisticated enough to prevent the
occurrence of breaks under normal circumstances. Protection
from internal and external corrosion is provided by use of
high-grade welded seamless pipe of adequate wall thickness,
by protective wrapping of the pipe, by use of corrosion
inhibitors and cathodic protection during operation, and by
placing the pipe deep enough in the ground. Figure 4-3 is
a photo of the Black Mesa pipeline as it exits from a pump
station. Accidental breakages caused by natural flows or
flaws in the pipeline are theoretically reduced to a mini-
mum.
Terminal At A Power Plant
At the power plant, the slurry must be dewatered. The
dewatering process is a particularly difficult aspect of
slurry pipeline operation. Common problems that have been
encountered in dewatering slurried coal include loss of coal
fines through the system because of inadequate flocculation
and removal and plastering in the feed ducts and in the
boiler because the coal remained too moist. The higher the
moisture content of the coal, the greater the heat loss
through the boiler, as illustrated in Figure 4-4.
68
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Figure 4-3. Photo of Black Mesa line as it exits from a pump station.
Coal fines discharged to a waste pond can cause fugitive
dust emissions if the water is allowed to evaporate.
Another potential problem is lowering of the flue gas
temperature below the acid dew point, which leads to corro-
sion of air heaters. The higher the moisture content of
the coal, the higher must be the temperature of the flue gas
to prevent corrosion. Change in ash composition can also be
caused by leaching of soluble compounds. The subsequent
effect on ash properties could result in fouling, slagging,
and ash fusion.
The loss in heating value of the coal due to its excess
moisture content was discussed in Section 3.4.
The dewatering of slurry and treatment of coal fines
are continuing problems that will likely be encountered with
future pipelines; at present these environmental problems
remain unsolved.
Fate of Slurry Water —
The literature indicates that a variety of chemicals
may be added to coal slurry to prevent corrosion of the
pipeline, to improve the velocity of the slurry, and to
maintain pH. The chemicals for this purpose include chromates,
phosphates, and various organic compounds. Dose rates may
be as high as 1000 ppm (39).
69
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--J
o
20
30
40 50
% MOISTURE IN COAL
60
70
80
Figure 4-4. Combustion heat loss as a function
of coal moisture content (350°F flue gas temp, assumed).
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The total accumulation of dissolved solids in slurry
water reflect the condition of the water in its natural
state and the soluble components of organic and inorganic
materials in the coal, corrosion products from the pipeline,
and additives. Mineral species in the coal can include a
range of soluble metals such as iron, aluminum, calcium,
sodium, and manganese, and anions such as chlorides, sulfates,
and carbonates. Dissolved organic compounds have not been
specifically identified.
The dissolved species that occur in slurry water
originate primarily from minerals in the coal. The major
classes of minerals in coal, according to Spackman and
Mores, and their potential for dissolution under various
conditions are described in the following text (40, 41).
Shale group - The principal shale minerals found in
coal are muscovite K2O 3Al2C>3 • 6SiC>2 • 2H20; illite K (MgAISi)
(AlSi3)Oio (OH) g; and montmorillonite (MgAl) 3 (Si^io) 3 (OH) 10 *
12H2O. These are complex silicates containing K, Al, and Mg
in various ratios. In general, silicates are insoluble in
water and weak acid solutions, an indication of low poten-
tial for dissolution in coal slurry lines.
Kaolin group - The principal kaolin mineral in coal is
kaolinite A1203 • 2SiC>2 • 2H20 . This is an aluminum silicate,
insoluble in water and acids, except HF. This mineral has a
low potential for solubility in coal slurry pipelines.
Sulfide group - Two principal sulfide minerals in coal,
pyrite and marcasite, have the same general formula FeS2-
Both minerals are virtually insoluble in water and dilute
acids, except HN03- The sulfide minerals are susceptible to
oxidation, however, especially in neutral or alkaline systems.
The oxidation of pyrite has been studied in much detail
because pyrite oxidation products are the principal contaminants
in acid mine drainage. Oxidation of pyrite can occur by
both chemical and biological mechanisms. The principal
oxidation products are FeSC>4, H2SO4, and hydrous ferrous and
ferric oxides, depending on the pH of the resulting solution.
Sulfide oxidation occurs more rapidly under conditions of
slight moisture and slightly elevated temperature, such as
might occur in a coal storage pile. One method of preventing
or minimizing the dissolution of sulfide oxidation products
is to slurry freshly mined coal. Weathered coal almost
invariably contains some sulfide oxidation products that are
soluble in the slurry water.
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Carbonate group - The principal carbonate minerals in
coal are calcite (CaCC>3) , siderite (FeC03) , and related
calcium, magnesium, iron carbonates. Carbonates are slightly
soluble in water. They can react with acidic components in
solution, however, and the resulting carbonate content of
the solution can be significant. Although carbonates, per
se, are not environmental problems, they can contribute to
water hardness and to scale formation. The dissolution of
iron carbonate may also discolor water.
Chloride group - Sylvite (KC1) and halite (NaCl) are
both extremely soluble in water. The solutions formed are
known to be corrosive. Removal of chlorides from the coal
by dissolution may in fact improve the coal ash combustion
characteristics. Chlorides in coal have been found to
contribute to corrosion of boiler tubes. The mechanism of
corrosion is more related to the Na and K content of the
ash, i.e. the Na and K content of the chlorides.
Oxide group - Quartz (SiC>2) , hematite (Fe^C^) , and
magnetite (Fe-^C^) are the common oxides found in coal.
Quartz is insoluble in water and acids and very slightly
soluble in alkaline solutions. Both hematite and magnetite
are insoluble in water but slightly soluble in weak acid
solutions. The oxides have no significant potential for
dissolving in slurry water.
Many other minerals are found in coal in trace or minor
amounts. Characterization of the mineral content of the
western coals, including the lignites and subbituminous
coals, remains to be completed. Some of the lignite and
subbituminous coals are reported to contain significant
uranium-bearing minerals, oralate, and nitrate minerals,
each of which has a different dissolution potential and thus
a different effect on slurry water.
At the power plant, the use of clarified slurry water
as part of the cooling tower makeup has the potential of
releasing metals into the atmosphere. Disposal of this
water as blowdown from cooling towers may also present a
problem if the water is leached underground from the storage
ponds. The potential for these types of problems depends on
the trace metal content of the slurry water and the extent
to which it is concentrated. Additional study is needed to
determine the effects of metals discharge in coal slurry
water.
72
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Aesthetics —
A pipeline is probably the most aesthetically positive
mode of coal transportation today. A buried pipeline is
visible only at occasional pumping stations and overpasses,
and is otherwise evidenced only by cut and fill areas.
After construction the right-of-way is returned to its
natural state except through forest lands, where it is kept
clear to allow surveillance. The land is free for travel by
vehicles, people, and animals. Agriculture and irrigation
may continue unobstructed when the pipe is buried deep
enough. In some cases future irrigation may be impeded
because the pipeline would obstruct ditches of a certain
depth.
Cut and fill areas are minimal because slurry can
continue to move through a pipe traversing steep terrain.
River crossings may be accomplished by placing the pipeline
below the riverbed. When the river has cut a large, steep-
sided gorge, an overpass must be built.
The overall adverse aesthetic impact can be very mini-
mal; in this respect the pipeline is superior to other modes
of transportation.
Abandonment
Abandoning a coal slurry pipeline would present no
major problems. Structures housing the preparation plant
and pump stations could be removed. Equipment would be sold
or reused and the steel recycled. The one disadvantage of
abandoning the pipeline is that the pipe steel may not be
recycled as economically as the steel in railroad rails.
IMPACTS FROM RAILROAD TRANSPORT OF COAL
Constructiong_f_Rail Line
Terrestrial impacts resulting from construction of a
new rail line are similar to those involved in construction
of a pipeline. Depending upon the terrain to be negotiated,
construction of a rail line may cause impact of slightly
greater magnitude. Since the pipeline can traverse terrain
not negotiable by train, the more indirect routes required
for railroad beds cover more ground and therefore cause more
73
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disturbance.
Removal of vegetation and increased human activity,
noise, and fugitive dust will cause the same impacts as in
pipeline construction. Again, policing of the construction
site is required to prevent the death of wildlife from
ingestion of small foreign objects.
The crossing of streams and rivers may pose a threat to
aquatic organisms, as in the laying of pipeline. Construc-
tion of a permanent bridge is likely to kill benthic organisms
in the immediate area, but colonies of such organisms
probably will become reestablished.
Upgrading an existing rail line will cause little, if
any, further adverse impact. The potential for disturbance
lies in the movement of construction vehicles and in noise
created by the vehicles and machinery.
Operation of the Rail Line
Operation of a rail line to transport coal can cause
pollutant emissions, noise, potential for fires, leaching of
chemicals, and detrimetal aesthetic effects. To illustrate
the magnitude of airborne contaminants emitted by unit
trains, we use as an example a 126-car train supplying
11,430 metric tons (12,600 tons) per trip (38). The unit
train is loaded at the mine site onto nine 2240-kW (3000-hp)
diesel locomotives for transport to the power plant 490 km
(306 miles) away. The locomotives are of the two-stroke
supercharged road variety. Upon arrival at the power plant
the coal is unloaded from the cars through bottom grates.
The total time for the haul from the mine and back is 48
hours. Emissions resulting from the 985-km (612-mile) round
trip are summarized in Table 4-2.
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Table 4-2. ATMOSPHERIC EMISSIONS FROM UNIT TRAIN ON
985-KM (612 MI.) ROUND TRIPb
Pollutant
Particulate
SO-
x
NO
HC
CO
Particulate, during loading
Particulate, during
unloading
Fugitive emissions, in
transit (0.05%)
Air emissions
kg (Ib)/round trip
345 (760)
780 (1,720)
4,855 (10,700)
2,075 (4,570)
935 (2,060)
2,285 (5,040)
2,285 (5,040)
5,700 (12,600)
a Load, one way: 11,430 metric tons (12,600 tons).
Based on data from reference (46).
The atmospheric emissions are from the diesel fuel
burned by the locomotives and fugitive emissions in transit
and during loading and unloading. The diesel emissions are
estimated on the basis of work output and fuel-based emis-
sion factors (35).
When an average load factor of 0.4 is used, the work
output for the 965-km (600-mile) round trip is 386,600 kW
(518,400 hp)-hr.
Because the work-output emission factors do not include
the other four pollutants (particulates, S02, aldehydes, and
organic acids) emitted from diesel trains, fuel-based emis-
sion factors are used to estimate these emissions. For a
0.4 load factor the fuel consumption for a 2240-kW (3000-hp)
locomotive is 265 liters (70 gal.)/hr, or 114,500 liters
(30,240 gal.) for the nine locomotives for the entire trip.
75
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Railroad electrification provides a possible means of
reducing the environmental impact of diesel-electric locomo-
tives. It reduces the emissions in transit, the energy
requirement (as petroleum), and the noise level. The emis-
sions are contained in a power station and thus are more
easily controlled. On the negative side is the need for
additional mining and combustion of coal, unless electricity
is supplied by some means other than coal firing.
Estimates of emissions during unloading are based on an
emission factor 0.2 kg/metric ton (0.4 Ib/ton) (uncontrolled)
(35). Figure 4-5 illustrates bottom unloading of a unit
train car over a hopper. If bottom dumping were done over a
trestle, no effort would be made to suppress the dust; no
emission factor is available for this method of unloading.
Estimates for discharge of particulates in loading are
assumed to be the same as in unloading, although no data are
available. Some loading operations include a negative-
pressure hood, which vents into a bag filter and reduces
emissions to a negligible amount; others provide no control
Figure 4-5. unloading of a hopper car from a unit train.
76
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Loss of particulates in transit varies with type of
coal shipped, condition of the cars, moisture and fines
contents of the coal, speed of the train, and wind speed.
The estimates of wind losses range from negligible to 1.0
percent of the coal shipped. Some reports place the losses
in certain situations at 5 tons per car during a trip over
480 km (300 miles) (42). The losses do vary widely, probably
averaging between 0.05 and 1.0 percent of the total coal
shipped. In the emission estimate given in Table 4-8,
windage losses in transit are assumed to be 0.05 percent.
Windblown coal that is lost to the environment will
cause some adverse impact. Coal dust will cover the leaves
of nearby vegetation and reduce its photosynthetic capabili-
ties. Also the coal dust could possibly have toxic effects
on wildlife that might browse on this vegetation. The dust
can clog the soil and prevent downward movement of precipitation,
Several suggestions have been presented for controlling
wind losses. Wind guards 30 cm (12 inches) high are partially
effective on rail cars. Washed coal retains much of its
moisture, which aids in reducing wind losses; the moisture
does evaporate, however, on a long, hot, arid haul. Sealing
the surface of each load with a latex-polymer or an asphalt
emulsion has been effective. Dustproofing the coal with oil
or calcium chloride with other substances added is common.
Corrosion inhibitors may be added to the chemical dustproof-
ing agents to prevent possible attack of metal firing equip-
ment and coal-handling parts. The quantity of material
required to provide effective dustproofing depends upon the
size and type of coal. The total surface to be treated
increases as the size of the coal decreases. Therefore,
more surfacing material must be applied to the finer coals.
Porosity and other mechanical characteristics also affect
the quantity needed. Application is most efficient while
the coal is in the air, as during loading, and the use of
properly designed hoods prevents waste of the dustproofing
materials.
Another method of controlling wind losses is the use of
removable tarpaulins on each car, as has been done with some
trucks that haul coal. This practice would be difficult and
expensive because of the labor required to attach and
remove the covers and the high rate of wear. Use of disposable
covers would be wasteful and would require incineration,
which entails further environmental problems.
77
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Flip-top lids for gondola cars (Figure 4-12) were
designed by Betchel Engineers in San Francisco for the
Milwaukee Railroad (43). The weight of the lids, 2.3/metric
tons (2-1/2 tons), is said to be justified on the basis of
preventing snow from settling in the cars on return trips
from the Ottertail Power plant to the South Dakota lignite
mines. Keeping the snow out reduces the freezing of coal to
the bottom of the car and is expected to reduce freezing
overall. The lidded cars have been in operation for less
than a year, and future observations will determine their
full value. Benefits derived from prevention of dust loss
and spillage and from keeping rain out are considered added
dividends and are thought to be insignificant.
Spillage deposits coal on the right-of-way, and a small
portion becomes airborne as it falls from the car. Some
spillage is caused by bumping. As each car is filled, it is
released from the loading point to bump against cars already
loaded. It is again bumped, perhaps several times, in the
yard where the trains are assembled, at the scales, and near
the point where the cars are cut out for local delivery at
the destination. Each car is bumped while enroute by
emergency braking and by each start-up of the train. Only
bumps of unusual severity cause spillage. All bumps cause
compaction, resulting in a smaller surcharge and exposing
less coal to spillage.
Noise --
The sources of noise in a moving diesel-electric
locomotive are listed below in descending order of noise
level (44):
- horn
- diesel exhaust muffler
- diesel engine and surrounding casing, includes air
intake
- cooling fans
- wheel/rail interaction
- electrical generators
Additional noise is produced by empty cars with loose
chains or vibrating parts.
Sources of noise in electric locomotives are as follows:
- horn
- cooling blowers
78
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- wheel/rail interaction
- electric traction motors.
Braking the locomotive from high speeds produces the
most noise because of the brake-cooling blowers. Other than
these periods of high-speed braking, the electric locomotive
is considerably quieter than the diesel-electric locomotive.
Mufflers on the exhaust system can greatly reduce the
noise from diesel locomotives. In addition, modified
casing with acoustical absorbent material around the engine
can successfully reduce overall engine noise. Studies of
noise from wheel/rail interaction have tested the possibili-
ties of a continuous welded rail, resiliant wheels, rubber
rail heads, and rubber tires. The most successful approach
thus far is use of the continuous welded rail, which achieves
noise reductions greater than 5 decibels. It may be possible
to incorporate this type of rail on portions of a route that
run near or through an urban center. Otherwise, proper
maintenance of the rail and bed will keep noise from this
source sufficiently low.
Fires --
In some of the semi-arid western states, sparks from
trains cause brushfires. Technology of roadside fire control
is continuing at a steady pace. Locomotives traveling
through countryside with abundant weeds and brush are being
equipped with the latest designs in spark retention arrestors
and nonsparking brake shoes (45). Composition brake shoes
reduce sparking the most, high-phosphorous shoes are second,
and the conventional cast-iron shoes cause the most sparking.
Control of fires will reduce the amount of wildlife habitat
destroyed by rail transport.
Vegetation Control --
Chemicals are used on rights-of-way to control the
growth of vegetation for both safety and aesthetic reasons.
Control of weeds and brush improves visibility, reduces fire
hazards, and provides a safer working environment for railroad
crews. There is some leaching of the herbicides and defoliants
and also of the preservatives used to retard deterioration
of wooden ties. Attention should be given to selection
of chemicals that are not only effective in controlling
vegetation but also nontoxic and nonpersistent.
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Aesthetics --
The right-of-way constitutes a permanent commitment of
the land surface, making the land unavailable for other
uses. Travel of vehicles and people across the committed
area is restricted. As with other forms of transportation,
the physiography of an area determines the extent of visual
impact and the means of minimizing detrimental impact.
Congestion at railroad crossings will increase as rail
traffic grows to meet the projected sharp increases in coal
production and consumption. Scheduling of the trains to
avoid heavy traffic hours should alleviate this problem in
most places. Although many railroad main lines already
bypass congested areas, some locales will suffer more than
others and additional bypass lines may be needed.
Abandonment
New methods for disposal of cross ties have been adopted
because of restrictions on burning (45). Ties are now given
away to persons who want them for architectural purposes or
fences; most ties, however, are so far deteriorated that
they must be hauled to approved sanitary landfills, to
special curtain destructors (for smokeless burning), or to
control locations where burning is allowed under special
permit and supervision. Some are cut up into small chips
at central points or at the site by mobile track machines.
Old ties may be burned as industrial fuel to utilize the
creosote content, but the resultant smoke is an environmental
drawback. In research studies, cross ties have been produced
by shredding old ties and reconstituting the chips. If mass
production by this method is possible, this could be a
feasible method for dealing with old cross ties. Some
paperboard manufacturers have shown interest in the waste
ties as raw material for their pulping processes. Until
these new methods can be developed, present methods of
utilization or destruction will be continued.
Rails contain 45 kg (100 Ib) of steel per foot or
approximately 280 metric tons/km (500 tons/mile) (23). When
a line is abandoned, the rails may be used again or sold as
scrap metal and remelted, depending on their condition. In
current practice, the 30.5-meter (100-foot) right-of-way is
abandoned and no effort is made to reclaim the land. A few
abandoned roadbeds have been turned over to the public as
paths for hiking or bicycling. Where this cannot be done,
the right-of-way should be graded and revegetated to encourage
reestablishment of native flora and fauna.
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IMPACTS OF BARGE TRANSPORT OF COAL
Construction as Related to Barge Us^e
Certain construction activities are related either
directly or indirectly to barge transportation. Dams and
locks are often required to keep waterways deep enough to
permit barge traffic. They are also built for other pur-
poses, such as flood control and recreation.
In other situations, waterways are dredged to maintain
navigable depths for barge transportation. Dredging pro-
duces some adverse impacts by eliminating certain benthic
organisms and increasing turbidity, which in turn may reduce
photosynthetic capabilities and possibly cause clogging of
fish gills.
Barge transport also requires docking cells near which
the barges are tied during loading and unloading. Usually
no more than two cells are required per barge. A cell is
simply a permanent pillar 60 to 90 cm (2 to 3 feet) in
diameter. When the cells are installed, turbidity may
increase temporarily, but little adverse impact is likely.
Barge Operation
Emission Estimate --
Barges are usually moved by a diesel tugboat. An
average barge shipment of coal on inland waterways is 18,000
metric tons (20,000 tons) (46). In the example given here,
the coal is loaded on barges at a site along the river. Ten
barges transporting 18,000 metric tons (20,000 tons) of coal
are lashed together, and a towboat with a 4475-kW (6000-hp)
diesel-fired power plant pulls the shipment to its destination,
The average speed of the towboat/barge system is 9.6
km/hr (6 mph), and the average rate of travel is 230 km (144
miles) per day a two day trip is considered typical. after
unloading at the destination, the tug returns the barges to
the shipping port empty. The emissions summarized in Table
4-3 and discussed below do not include the return trip.
One source of air emissions from barges is the com-
bustion of diesel fuel in the towboat. On the basis of an
energy requirement of 139,000 g-cal/metric ton (500
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Btu/ton) estimated by the American Waterways Operators, the
average fuel consumption for a towboat burning 9.2 x 10 g-
cal/liter (138,000 Btu/gal) diesel fuel is 39,400 liters
(10,400 gal.) per day-
Table 4-3. SUMMARY OF ATMOSPHERIC EMISSIONS IN
BARGE TRANSPORT OF COAL3
Basis: 18,100 metric tons (20,000 tons) of coal
Particulates
so2b
x
HC
CO
Particulate, during
loading
Particulate, during
unloading
Fugitive dust, in
transit
Air emissions,
kg (lb)/day
61 (135)
127 (280)
1746 (3,850)
203 (447)
1061 (2340)
3630 kg (8,000 lb)/trip
3630 kg (8,000 lb)/trip
1800 (4000)
Based on data from (38).
Based on a diesel fuel sulfur content of 0.2 wt
percent.
A typical barge loading station would include a rail-
road car dump, thawing sheds, overland belt conveyor, loading
conveyor, and loading chute. This system is used to transfer
coal hauled from the mine on an inland railroad to barges on
a major waterway. Such systems are located mainly on the
Appalachian rivers, with a few recent additions on the
Mississippi River. The development of western coal will
require additional capacity on the Mississippi watershed.
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Data on emission factors for uncontrolled loading of
barges are not available; the emissions probably are similar
to those estimated for unloading of rail cars, discussed
earlier (0.20 kg/metric ton or 0.4 Ib/ton). On this basis,
for the 18,100-metric-ton (20,000-ton) barge shipment
discussed here, 3630 kg (8000 Ib) of dust would escape
during loading.
Barge unloading stations are usually located in more
densely populated areas than are the loading stations. They
are at power plants, industrial sites, or at points for
transfer of coal to a railroad or truck for inland delivery-
They are located on the Ohio and Mississippi Rivers and on
some of their tributaries,
A typical unloading station would include a clamshell
to pick up coal from the barge, a receiving bin with feeders,
and an overland conveyor to the stockpile.
Relatively small amounts of fugitive dust are generated
as the clamshell removes coal from the barge and drops it
into the bin. The amount of dust liberated in a high wind
can be substantial. There is little available control of
dust as coal is picked up in the barge.
The receiving bin can be equipped with sprays on the
feeder discharge points to control the dust. The sides can
be extended to permit lowering of the clamshell to a position
protected from wind before discharging. Maintenance of a
negative pressure in the bin to provide a downward flow of
air from the top of the bin will reduce dust emissions,
which can be further suppressed with a dust collector. It
is assumed that uncontrolled emissions would be similar to
those described earlier regarding railroad impacts (0.20
kg/metric ton or 0.4 Ib/ton); thus in this example 3630 kg
(8000 Ib) would be lost during barge unloading.
A very small part of the coal transported in barges is
lost accidentally. An occasional wreck can deposit several
thousand tons of coal into the river. This coal would wash
downstream and become a part of the river bottom. When this
happens, the benthic life inhabitating the covered areas is
likely to be eliminated. This should not be a long-term
impact, because similar benthic organisms nearby will
repopulate the disturbed area.
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Fugitive dust escaping from a loaded barge during
transit constitutes an unknown loss. This loss is very
small because the velocity of the barge is low and only the
peak portion of the loaded coal is exposed above the sides
of the barge. Hittman Associates estimate that fugitive
dust from barges in transit would be negligible (37). The
barge emission estimate in Table 4-3 assumes windage losses
of 0.02 percent, over the two day trip.
This source of dust could be eliminated by the use of
covered barges, which are in common use for transport of
other bulk materials.
Noise —
Towboats are probably the least important source in
terms of noise impact on a community, although noise levels
on board may be high. Most of the noise generated by the
propulsion system is radiated into the water. Hull noises
are primarily low-frequency. Horn blasts are generally the
only loud noises that affect residents of a town or city.
Aesthetics —
The aesthetic impact of barge transport has two basic
features: 1) the appearance of a dammed river as opposed to
a free-flowing river and 2) the sight of barges moving back
and forth on the river. Since river transport includes far
more than coal movement, the return of major rivers to a
free-flow state is impractical. The extent to which a river
is used to transport coal may become a public issue if coal
barge traffic increases at the projected rates.
IMPACTS FROM OVERLAND BELT CONVEYOR TRANSPORT OF COAL
Construction
Impacts of construction can be held to short-term
effects with careful planning. The use of land for right-
of-way requires room for the conveyor system, a service
road, and power lines. Width of the right-of-way can range
between 15 and 60 meters (50 and 200 feet), depending mainly
on the type of terrain, which may necessitate cut and fill
operations and diversion of the road from the belt. Land
owners may require that the company buy an entire block of
land rather than allowing a 15-meter (50-foot) right-of-way
through it.
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Construction work for conveyors, as with pipelines and
railroads, results in several environmental impacts:
erosion and sedimentation, air pollution, noise, and destruc-
tion and disturbance of flora and fauna.
Air pollution results .from dust and diesel equipment,
and a small amount from workers' automobiles emitting HC,
NOX, and CO. Dust can be controlled in part by watering the
roads and reseeding exposed areas. After construction is
completed, the belt conveyors are operated by electric
motors and air pollutants are minimal.
Noise and human activity will affect fauna during
construction, but these effects should be minimal along the
belt line upon completion.
A completed conveyor system basically follows the
terrain. Major cut and fill areas can be avoided, and
ponds, streams, and drainage patterns left unaltered.
Operation
The primary impact of conveyor belt operation is spill-
age and fugitive dust emissions at feeding, transfer, and
discharge points, and enroute on the belt.
Over a long distance, an uncovered belt conveyor could
lose a significant amount of its load as fugitive dust in a
high wind. Though the belts are covered along their length,
they are not entirely surrounded by the covering as are
shorter conveyors. Belts are covered mainly to prevent rain
from wetting the coal and accumulating on the belt where it
dips through a valley, and to prevent wind from overturning
the belt. In our estimates, the fugitive dust losses from
long-distance belts are assumed to be 0.02 percent.
Water and mud from the material being conveyed cling
to the belt and fall from the return strand. Belt scrapers
and wipers remove the main part of this material at selected
points, and the remainder falls at places of natural accommo-
dation.
Water and mud can be controlled by properly maintaining
the belt cleaning equipment and by installing drip pans
under parts of the conveyor as required to catch the remainder
of the drip. Drip pans are normally installed where the
conveyor crosses highways, roofs, or walkways. The drip
pans must be cleaned occasionally by hand.
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Transfer stations are usually enclosed to minimize
discharge. Some are hooded and vented to a dust collector.
Both the enclosure and the hooding greatly reduce fugitive
emissions from transfer operations.
Spillage occurs while the conveyor is being aligned and
adjusted and the belt is being trained. A break in the belt
will also cause spillage, possibly requiring that the belt
be unloaded by hand. Spillage must be recovered by hand
from traveled areas when normal operation is resumed. Re-
covering coal spilled on the ground requires shoveling it by
hand into a truck; accordingly, most of the spilled coal
probably remains on the ground.
Control and safety features include electrical belt
slip detectors, which measure drive speed with respect to
belt slips on the drive pulley. Belt drift switches at each
side of the belt react if the belt drifts out of line.
Maintenance and wear can be reduced by use of mechanical
turnovers at each terminal to present the clean side of the
belt to the training idlers on the return trip. The turnover
prevents the residual coal on the belt from coming in contact
with the idlers.
Air Emissions Estimate --
Environmental Research and Technology (ERT) has provided
an emission estimate of 0.10 kg/metric ton (0.20 Ib/ton) for
conveyors in coal processing operations (47). Since this
value seems high in comparison with estimates for conveying
other materials, it may be that the ERT emission factor for
the processing area includes other unidentified particulate
(34). The value is not compatible with the relatively
high control efficiencies, usually at least 90 percent,
associated with enclosed transfer and conveying systems.
Hittman Associates state that coal conveyor systems are
either covered or operated at such a speed that dusting does
not occur to any great extent (37). Their report also cites
the relatively small amounts of coal that are transported by
conveyor. Their value for loss through spillage at conveyor
transfer points is 0.04 percent or 0.4 kg/metric ton (0.8
Ib/ton). At this rate, even if only a few percent of the
spillage losses are in the form of dust, emissions from coal
conveying would be comparable to those from coal storage
piles.
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Monsanto Research Corporation sampled conveying operations
at a granite quarry and determined that fugitive dust emissions
from conveying crushed granite are negligible (36). The
report does not mention whether the conveyor was enclosed.
Fugitive emissions can be estimated on the basis of an
example operation: the 16-km, 122-cm (10-mile, 48-inch)
conveyor from the Meigs Mine to the Gavin plant, near Galli-
polis, Ohio. This belt operates at a rate of 1800 metric
tons (2000 tons) per hour and on a typical day transports
29,000 metric tons (32,000 tons) of coal. Assuming that the
windage losses through conveying are 0.02 percent, and using
an emission factor of 0.075 kg/metric ton (0.15 Ib/ton)
controlled for spillage at transfer stations (there are
three along the belt), the amounts of coal lost per day
would be 5760 kg (12,800 Ib) by windage and 6530 kg (14,400
Ib) from all transfer points combined.
Aesthetics --
A conveyor system traverses a relatively narrow right-
of-way. However, it is also a continuous operation that
remains a permanent part of the landscape. Its intrusion on
the visual scene is especially noticeable at the sites of
large trestles, overpasses, and cut and fill areas. Total
aesthetic impacts, of course, are highly variable.
Abandonment
Belt conveyors are supported on concrete piers, which
are usually abandoned rather than removed and constitute a
continuing eyesore as well as a hazard.
Removal of all steel and concrete structures and a
small amount of grading and reseeding would restore the land
to near its original state.
Truck Operation
Most environmental studies are directed at the effects
of trucks using the highways. The use of large trucks in
off-highway transport involves many of the same noise and
emission problems and additional environmental impacts
related to building, maintaining, and abondoning mine roads.
Transporting coal with a diesel truck involves two
crossings of a given point for each truck load, one loaded
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and one empty. Increasing transportation of coal by truck
would require redesign of many roads and would increase
maintenance costs. It would also create more noise, pollutant
emissions, and safety hazards.
Use of Trucks at Mine Sites --
Mine roads generally consist simply of graded and
compacted soil, with occasional addition of crushed clinker.
The roads are 15 to 24 meters (50 to 80 feet) wide and are
designed for continuous use by heavy off-highway vehicles.
During construction of the roads, topsoil should be
saved and banks seeded. Culverts are needed wherever the
road crosses natural surface drainage channels. Settling
basins should be constructed downstream from the culvert
crossing to collect material that may wash from the haulage
road or from mined areas not yet reclaimed.
The 180-metric-ton (200-ton) trucks pulverize the
surface of the roads and create a layer of fine dust. When
the dust falls on plant leaves, it reduces transpiration
through stomata and decreases photosynthesis.
Control is recommended not only for environmental
reasons but also to prevent damage to equipment. Control
consists of watering the roads throughout the work day with
truck-mounted spray equipment.
Emission Estimate - Trucks --
Sources of emissions from trucks are exhausts from
diesel and gasoline engines, windage losses, and spillage.
Emissions from truck transport are illustrated by use of the
following example:
1) Diesel-powered uncovered truck with 27-metric-ton
(30-ton) payload; 20 miles one way haul, empty
return.
2) Diesel fuel consumption of 1.5 km/liter (3 1/2
mi/gal.) loaded and 2.1 km/liter (5 mi/gal.) empty
= 37 liters (9.72 gallons)/truck.
3) Loss of coal in transit assumed to be 0.05 percent
of total payload; loss in unloading and loading
assumed to be 0.04 percent.
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Table 4-4 summarizes atmospheric emissions from truck
transport of coal. The emission factors are the same as
those used for barges (35).
Table 4-4. ATMOSPHERIC EMISSIONS FROM TRUCK
TRANSPORT OF COAL
(Payload of 27 metric tons (30 tons)
Pollutant
Particulate
S02
CO
HC
N02
Aldehydes (HCHO)
Organic acids
Fugitive dust in transit
Fugitive dust loading
Fugitive dust unloading
Emissions
Kg/trip
0.06
0.12
0.98
0.16
1.62
0.01
0. 01
27
14
14
Ib/trip
0.13
0.26
2.18
0.36
3.60
0.03
0.03
60
30
30
One pound = 0.4536 kg.
Dust Control --
Very little is done to reduce the production of dust
during loading and transporting coal within the mining area
(See Figures 4-6 and 4-7). When inherent moisture of the
coal is 3 percent or greater, initial dust control may be
unnecessary- A few coal companies use a large tank truck
with a built-in sprinkler system to suppress dust in exposed
coal beds as well as on mine roads.
Wind loss and spillage will occur during transport
unless the top of the truck is covered. No data are available
on the magnitude of fugitive dust emissions. The amount lost
during a trip would depend on variables similar to those
affecting fugitive dust emissions from a rail car. The
example for trucks in this section assumes 0.05 percent of
the load lost as fugitive dust. Hittman Associates estimate
windage losses from loading and unloading to be 0.04 percent
of the total coal transported but assume windage losses in
transit to be negligible (37). Organic sealants would
reduce wind losses but not spillage. Barring accidents,
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Figure 4-6. Example of fugitive dust from unloading at a coal mine.
Figure 4-7. Dust from haul roads at a coal mine.
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proper covering is the only way to contain the coal totally
during transit. Better-designed trucks with covered aluminum
bodies are now appearing on highways. Spillage and dust
remain a problem with the older uncovered trucks; they could
largely be eliminated by providing covers.
Damage to Roads --
A study by the Kentucky Department of Transportation
indicates that damage to roads by trucks is the most destruc-
tive environmental impact associated with truck transporta-
tion. Many of the Kentucky highways used for coal hauling
do not have an adequate base and therefore are unsuitable
for heavy loads (48). The Department of Transportation
estimates that bringing all roads but local ones up to an
acceptable design standard for normal travel purposes would
cost $1.9 billion and that $335 million would be needed to
provide sufficient structural conditioning to support heavy
coal hauling.
Noise —
The major sources of noise from trucks are from the
engine, exhaust, cooling fans, and tires.
The high-compression diesel truck engine causes more
vibration and thus produces more noise than does the spark-
ignited gasoline engine. Experiments have been done with
modifications of combustion chambers and timing and with
block and crankcase reinforcement, but little success is
reported. Engine covers and panels have proved to be the
most successful short-term approach to reducing noise.
Exhaust noise dominates other truck noise, producing
about 100 dB; exhaust noise can be controlled. Mufflers can
easily reduce the noise level to 90 dB, and research is
being conducted to reduce it to the 75-dB range measured at
15 meters (50 feet). Possible innovations include placing a
resonator close to the exhaust manifold, exhaust pipe wraps,
and double-wall or laminated exhaust pipe.
Noise from tires ranges from 80 dB to over 90 dB, and
tires become the dominant noise-producing source at speeds
above 80 km/hr (50 mph). With current technology, however,
these noise levels cannot be reduced without significant
impacts on operating cost and safety. The noise produced by
cooling fans, intake valves, aerodynamic turbulence, and
"rattles" is highly variable. Techniques for reducing noise
from these sources are under study.
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Abandonment
Abandoned roads must be reclaimed in a manner that will
minimize erosion and encourage the reestablishment of native
vegetation and wildlife habitat. If the road surface
material is not suitable for revegetation, it should be
removed and reused or disposed of within the mining area.
Reclamation includes scarifying and shaping the roadway,
adding topsoil as needed, and seeding the surface.
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SECTION 5
RECOMMENDED RESEARCH AND DEVELOPMENT OF CONTROL TECHNOLOGY
Table 5-1 summarizes the adverse impacts of coal
transportation for which controls are now lacking or inadequate.
These impacts are rated on a scale of 1 to 3 (1 = highest
priority) to indicate the relative importance of the research
and development studies required to provide effective control
technology. All of the adverse impacts of constructing and
operating conveyor belts and barges (excluding diesel engine
emissions) can be rectified by application of controls now
available. Proposed studies dealing with the other aspects
of coal transport are discussed briefly in the following
paragraphs. It is assumed that each of the proposed research
and development efforts would include a detailed cost study
that indicates trends and provides a basis for cost/benefit
analysis.
COAL CLEANING
Research is needed on means of reducing NOX emissions
from thermal dryers by modification of the combustion
process (38). A survey should be conducted to evaluate
effectiveness of scrubbers, de-dusters, and other equipment
used for particulate control on thermal dryers.
Because coal refuse piles often cover many acres of
ground, means of preventing combustion of refuse piles
should be developed and implemented.
Effluents from coal cleaning plants should be charac-
terized with respect to trace elements, both qualitatively
and quantitatively. If toxic elements are found at dangerous
levels, technology should be developed for treating these
effluents before discharge.
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Table 5-1. PRIORITIES FOR RESEARCH AND DEVELOPMENT OF
ENVIRONMENTAL CONTROLS FOR COAL TRANSPORTATION
Mode
Impact
Priority
Coal cleaning
Coal storage
Crushing loading,
unloading
Pipelines
Railroads
Trucks
Particulate and NOX emissions
from thermal dryers
Fugitive dust, refuse piles
Water effluent - toxic
properties
Fugitive emissions
Water runoff - toxic
properties
Quantification of emissions
Breakage
Availability of water
Reslurrying methods
Slurry dewatering
Fines treatment
Slurry water - toxic
properties
Corrosion inhibitors -
toxic properties
Noise
Fugitive dust, spillage
Diesel engine emissions3
Road damage
Fugitive dust, spillage
Noise
2
2
1
2
1
2
1
1
2
1
1
2
2
2
1
2
2
Also applies to barges and trucks
Priority key
1 = High
2 = Medium
3 = Low
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COAL STORAGE
Control of windage losses from open coal storage piles
is most feasible for application to dead storage. Since
live storage involves continuous addition and removal of
coal, effective control with chemicals is difficult.
Research on control of fugitive losses from dead coal stor-
age piles should continue, with emphasis on development of
an innocuous chemical that holds the coal in place yet
allows it to break up easily when it is reclaimed from the
pile.
Characterization of the runoff from coal storage piles
should be completed. As with coal slurry water,- when the
toxic elements of coal pile runoff have been identified,
appropriate control methods and regulations can be deter-
mined.
CRUSHING, LOADING, AND UNLOADING
Studies are needed to determine the range of emissions
from the crushing, loading, and unloading processes as-
sociated with all modes of coal transportation. Another
PEDCo report (50) provides recommendations for research and
development on means of reducing fugitive dust from crushing
and loading at coal mines. The recommendations, which are
applicable also to such other operations as loading and
unloading at rail and barge facilities, emphasize the need
for quantifying emissions to provide an accurate data base.
Established control methods such as water sprays and
hooding should be used at locations where crushing, loading,
and unloading activities constitute a hazard to health or
cause damage to vegetation or structures.
COAL SLURRY PIPELINES
Pipeline Break
Emergency procedures should be developed for cleanup of
an area affected by a pipeline break, especially in or near
a body of water. Environmental impact statements for
proposed pipelines should include an emergency procedure for
cleanup. In planning of future coal slurry lines, emphasis
should be placed on situating the lines in locations remote
from sensitive receptors such as agricultural lands and
densely populated areas.
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Water Availability
Much additional study is needed on availability of
water for proposed pipelines and the effects on adjacent
areas, especially in the semiarid western states. The data
now available concerning aquifers in the semiarid western
states (the Madison Aquifer in Wyoming, for example) are
generally inadequate and conflicting. Proponents of a
pipeline may specify a fixed quantity of water, in hectare-m
(acre feet) per year; however, during the early years of
operation additional water may be needed if the line is not
pumping coal at full capacity.
The availability of water and the effects of water
usage are crucial factors that will determine whether
pipelines can become a feasible transport alternative.
Reslurrying at Pump Stations/Power Plants
An economical method is needed for keeping in sus-
pension the coal that is dumped from a line during emer-
gency. Use of storage tanks with agitators might provide a
better system than dumping the coal in a pond, especially in
populated areas where leaching or runoff of coal slurry
water may cause problems. The use of tanks would also
eliminate emissions of fugitive dust from storage of dried
fine coal.
Coal Slurry Dewatering and Treatment of Coal Fines
Operation of the Mojave power plant indicates that
dewatering of the coal slurry is a major problem. Extensive
modifications of the centrifuges, such as the use of ceramic
materials for face plates on the screw flights and other
high-wear areas, are just beginning to be applied. Research
is needed on other means of dewatering coal slurries, such
as the deep cone thickener used in England and improved
versions of the old plate and frame filter press (38).
Treatment of coal fines needs further development.
Cleaning of the fines or the entire coal slurry at the power
plant followed by drying could possibly increase the Btu
content of the coal and provide a means of utilizing the
coal fines.
Studies are also needed on (1) the effects of coal
slurry firing on boiler combustion; (2) effects of changes
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in ash composition due to leaching of soluble compounds on
fouling, slagging, and ash fusion; and (3) performance of
air pollution control equipment.
Chemicals in Slurry Water
Characterization of the soluble salt content of coals
should be completed; we should further determine how much of
these salts will leach into transport water, especially in
western coals. The dissolved organic compounds also should
be identified.
When sufficient data on minerals and organics in slurry
water are available the possible toxic effects of slurry
water on groundwater or streams can be evaluated. Potential
release of trace elements from cooling towers using slurry
water could be studied.
The effects of corrosion inhibitors on the toxicity of
slurry water also should be determined.
If the Clean Water Act requires zero discharge for
slurry water, application of technologies such as ion ex-
change membrane separation and forced evaporation should be
researched.
RAILROADS
Noise
Locomotive builders are studying ways to attenuate
diesel locomotive noise and noise caused by switching
operations and wheel-rail interaction. These studies should
concentrate on solving the noise problem at the source.
Techniques for noise reduction in switching operations and
wheel-rail interaction are needed mainly where trains pass
through urban areas.
Fugitive Coal Dust and Spillage
More data are needed to determine the seriousness of
blowing dust and spillage, since many railroad operators
indicate that fugitive emissions are not a significant
problem. In many cases blowing dust is receiving attention
for economic rather than environmental reasons. It is known
that blowing dust from trains can cause nuisance problems.
Spillage of coal from trains depends on the condition of the
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cars and the methods of handling during loading and during
transport.
Research into control of fugitive coal dust from trains
is directed toward developing sprays that will hold the coal
fines in place at a reasonable cost, are innocuous with
respect to the ultimate use of the coal, and allow the coal
to break up readily when the rail car is unloaded.
Diesel Engine Emissions
Diesel engine manufacturers are working on reducing
emissions of NOX, hydrocarbons, and particulates from
stationary and mobile diesel engines. Following are other
areas that require additional research and development (38,
51) :
1. Materials to inhibit NOX formation that could be
introduced into the combustion process through a
fuel additive.
2. Engine refinements such as derating engine output,
adjusting variable compression ratio; injection
modification; use of precombustion chambers.
3. Reduction of the peak combustion temperature by
introducing an inert material such as exhaust gas
or water.
TRUCKS
The unsolved environmental problems of truck transport
are damage to roads, fugitive emissions, and noise.
Road Damage
Damage to Kentucky roads caused by coal trucks in-
dicates that similar problems can be expected in other areas
where highways are not designed for such heavy loads. One
direct method for eliminating the damage is to forbid
operation of coal trucks on roads not designed for their
use. Other suggestions focus on meeting the cost of up-
grading the roads (48):
98
-------
1. A tonnage tax for use of county roads.
2. An export tax on coal.
3. A ton-mile tax specifically for the coal hauler.
Dust Control
Newer designs of coal trucks minimize fugitive emis-
sions and spillage on public highways, although emissions
are not controlled for in-mine hauls. More emphasis should
be placed on proper maintenance of older trucks to minimize
spillage and on provision of covers or use of chemical
sprays to reduce emissions in transit. These recommendations
are most applicable to use of public roads for coal hauling.
Noise
Reduction of truck noise is complicated, and finding
satisfactory methods may require considerable time. With
increased public and legislative pressure, truck designers
are developing new procedures and designs, some of which are
discussed in section 4.6, that will reduce noise levels
(52) .
Research should continue on reducing noise from truck
engines, exhausts, and tires to the lowest level possible
without detrimental effects on operating safety and cost.
Emphasis should be placed on reducing noise at the source
rather than on use of shields or covers as secondary noise-
reduction devices.
99
-------
REFERENCES
1. U.S. Bureau of Mines Bulletin 667, Mineral Facts and
Problems, 1975 Edition.
2. U.S. Bureau of Mines and U.S. Geological Survey, Coal
Resources Classification System of the U.S. Bureau of
Mines and the U.S. Geological Survey. U.S. Geological
Survey Bull 1450-B. 1967, 7 pp.
3. Principles of the Mineral Resource Classification
System of the U.S. Bureau of Mines and the U.S. Geo-
logical Survey- U.S. Geological Survey Bull. 1450-A.
1976, 6 pp.
4. Averitt, P. Coal Resources of the United States,
January 1, 1974. U.S. Geological Survey Bull. 1412,
1975, 131 pp.
5. Hamilton, P.A., D.H. White, Jr., and T.K. Matson. The
Reserve Base of U.S. Coals by Sulfur Content (In Two
Parts). 2. The Western States. BuMines 1C 8693,
1975, 322 pp.
6. Thomson, R.D., and H.F. York. The Reserve Base of U.S.
Coals by Sulfur Content (In Two Parts). 1. The
Eastern States. BuMines 1C 8680, 1975, 537 pp.
7. Chemical Engineering, April 1976.
8. Coal-Slurry Pipelines ... A Rapidly Growing Technique
Coal Age. July, 1974.
9. Battell Memorial Institute - Proceedings of the Inter-
national Technical Conference on Solid, Liquid Slurry
Transportation, February 3 and 4, 1976.
10. SME Mining Engineering Handbook, Vol. 2, 1973.
11. U.S. Bureau of Mines Circular IC8543, Technology and
Use of Lignite "Black Mesa - Pipeline Transport of
Liquid Coal," Jack Ellis and Peter Bachatti, 1972.
100
-------
12. G. Barthauer, et al., Consolidation Coal Co., U.S.
Patent No. 2791472 - "Use of Inhibitors to Reduce
Corrosion of Pipelines," 1957.
13. J. P. Kinney, et al., Patent No. 3,762,887, "Liquid
Fuel Consumption," Consolidated Coal Co.
14. Chemical Abstracts 30838, "Preparation Transportation
and Combustion of Coal." 1966.
15. Chemical Abstracts 127077b, "Properties of Coarsely
Dispersed Water-Coal Suspensions." 1971.
16. Unit Trains Have Revolutionalized Coal Delivery.
Electrical World. June 1, 1975.
17. 1974 Keystone Coal Industry Manual.
18. Minerals Yearbook, v.I. Metals, Minerals, and Fuels.
U.S. Department of the Interior, Bureau of Mines.
Washington, D.C., Annually.
19. No Two Coal-Handling Systems Are Alike. Electrical
World. June 1, 1975.
20. Rail Transport Dominates . . . Coal Age. Mid-May 1975.
21. Larwood, G.M., and D.C. Benson. Coal Transportation
Practices and Equipment Requirements to 1985. U.S.
Department of the Interior. Bureau of Mines, Eastern
Field Operation Center, Pittsburgh, Pa. Information
Circular 8706. 1976.
22. Kentucky's Coal Transportation, A Special Situation
Report, Coal Markets, Distribution, and Movement.
Kentucky Department for Transportation, Kentucky
Development Cabinet, and Kentucky Institute for Mining
and Minerals Research. June 1975.
23. Rieber, et al. The Coal Future: Economic and Tech-
nological Analysis of Initiatives and Innovations to
Secure Fuel Supply Independence, Center for Advanced
Computation, University of Illinois at Urbana-Champaign,
May 1975.
24. Coal Slurry Pipeline Legislation. Hearings Before the
Committee on Interior and Insular Affairs. House of
Representatives. Ninety-Fourth Congress, First Session
on H.R. 1863, H.R. 2220, H.R. 2553, and H.R. 2986.
1975.
101
-------
25. Project Independence. Federal Energy Administration,
Under Direction of U.S. Department of the Interior.
November 1974.
26. Bituminous Coal and Lignite Distribution Calendar Year
1975. U.S. Department of the Interior, Bureau of
Mines, Washington, D.C. April 12, 1976.
27. Coal Section and Handling. Power, 118, S-6, February
1974.
28. Hittman Associates - Environmental Impacts, Efficiency,
and Cost of Energy Supply and End Use, Vol. I, II,
January, 1975.
29. Steam, Its Generation and Use, Babcock and Wilcox,
1974.
30. Communication with the American Waterways Operators,
Inc.
31. Communication with American Electric Power Co. personnel.
32. Environmental Protection Agency, Office of Air Quality
Planning and Standards, Background Information for
Standards of Performance: Coal Preparation Plants, 2
Vol. Vol. 1, Proposed Standards; Vol. 2, Summary of
Test Data, EPA Research Triangle Park; NC (1974).
33. Sussman, V.H. Nonmetallic Mineral Products Industries.
In: Air Pollution, Vol. Ill, A.C. Stern (ed) New York
City Academic Press. 1968.
34. Evaluation of Fugitive Dust Emissions from Mining, Task
1 Report, Identification of Fugitive Dust Sources
Associated with Mining. PEDCo Environmental, Inc.,
Cincinnati, Ohio. Prepared for U.S. Environmental
Protection Agency, Cincinnati, Ohio. April 1976.
35. Development of Emission Factors for Fugitive Dust
Sources, U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina, Publication Number EPA
450/3-74-037. June 1974.
36. Fugitive Dust from Mining Operations--Appendix, Final
Report, Task No. 10. Monsanto Research Corporation,
Dayton, Ohio. Prepared for U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina. May
1975.
102
-------
37. Hittman Associates, Inc. Environmental Impacts, Effi-
ciency, and Cost of Energy Supplied by Emerging Tech-
nologies. Draft Report on Task 5, low Btu gasification
of coal and Task 6, high Btu gasification of coal.
Columbia, Md. February (1974) .
38. Radian Corporation, "Atmospheric Pollution Potential
from Fossil Fuel Resource Extraction, On-Site Process-
ing, and Transportation". EPA-600/2-76-064. March
1976.
39. U.S. Patent No. 2791472 - Use of Inhibitors to reduce
corrosion of pipelines. G. Barthauer et as Consol.
Coal. 1957.
40. Occurrence and Dist. of Minerals in Illinois Coal.
Illinois State Geol. Survey. Circ. 476. 1973.
41. Handbook of Chem. and Physics. 45th Ed. 1964.
42. Coal Age, July 1974. "From Mine to Market By Rail".
43. Private Communication with Ottertrail Power Plant
Personnel April 1976. Electric World, June 1, 1975.
44. Transportation Noise and Noise from Equipment Powered
by Internal Combustion Engines. U.S. Environmental
Protection Agency. December 31, 1971.
45. Environment and the Railroads. Sub-Council Report
August 1973. National Industrial Pollution Control
Council (NIPCC).
46. Battelle-Columbus Laboratories, "The Transportation of
Solids in Steel Pipelines."
47. Air Pollutant Emissions in the Northwest Colorado Coal
Development Area. Environmental Research and Technology -
Westlake Village, California. 1975.
48. Kentucky Department of Transportation, Kentucky's Coal
Transportation, A Special Situation Report, Coal Markets,
Distribution and Movement. June 1975.
49. Staadt, Richard L. International Harvester Co. "Less
Noise From Diesel Trucks", Society of Automotive
Engineers, West Coast Meeting. 1973.
103
-------
50. PEDCo Environmental, Inc. "Evaluation of Fugitive Dust
Emissions from Mining, Task I Report, Identification of
Fugitive Dust Sources Associated with Mining," April,
1976.
51. National Industrial Pollution Control Council, "Environ-
mental and Railroads" sub-Council Report, August, 1973.
52. U.S. Environmental Protection Agency, "Transportation
Noise and Noise from Equipment Powered by Internal
Combustion Engines (1971).
104
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APPENDIX A
GROUNDWATER RESOURCES AND THE RELATIONSHIP
TO USE OF COAL SLURRY PIPELINES
CENTRAL WESTERN RIVER BASINS
Total water resources in the United States are suffi-
cient for projected energy growth. In some locales, however,
particularly in the western states, water supplies are
limited. In the East, South, Midwest, and along the seacoast,
water supplies generally are adequate for industrial and
domestic use. West of the 100th median, industries must
compete for the limited available water supplies. Figure A-
1 indicates the relative abundance and deficits of water
resources across the United States. Water abundance is
defined as rainfall greater than evaporation rate, and water
deficit, as the opposite.
Water needs in the central western states are currently
met by a combination of surface and groundwater withdrawals.
Although surface water supplies in the southernmost states
of Arizona and New Mexico are limited, supplies in the
northern states are relatively abundant. In the southernmost
states, groundwater is being overdrawn to compensate for
deficiencies in surface water supply-
The western states of major concern with reference to
water availability for coal development are North Dakota,
Montana, Wyoming, Colorado, New Mexico, and Arizona. Of the
eight river basins in these states, only those of the upper
Missouri the upper and lower Colorado, and the Rio Grande
are of concern.
105
-------
WATER SURPLUS OR
DEFICIENCY INCHES
20 TO >80
0 TO 20
0 TO -20
-20 TO >-40
Figure A-l. Abundance of water in the U.S. (Source: Ref. A-l).
-------
Upper Missouri River Basin
The Fort Union Powder River Basin Coal Region is the
major energy source in the Upper Missouri River Basin
(Figure A-2). It is estimated that this coal region con-
tains 34 billion tons of strippable coal deposits (Ref.
A-l). Surface water, however, is poorly distributed in time
and space. Use of surface water in coal development in
parts of the area would require storage reservoirs and
distribution systems, whereas in other parts the surface
water is fully appropriated and its use in coal development
would deprive the present users.
Preliminary investigations conducted by the U.S.
Geological Survey and by State agencies of Wyoming, Montana,
and South Dakota indicate that Madison Limestone and as-
sociated rocks may provide a significant percentage of the
water requirements for future coal development. Preliminary
data indicate that the yield of wells pumping from the
Madison aquifer may range from about 1.3 liter/s (20 gal./
min) to 570 liter/s (9,000 gal./min); most, however, are
less that 63 liter/s (1,000 gal./min) (Ref. A-2).
Although various institutions and authors have con-
ducted hydraulic studies, few reports provide quantitative
data on the hydraulic characteristics of the aquifer; on the
relation of the aquifer to springs, streams, and the under-
lying or overlying aquifers; or on the recharge to, movement
through, and discharge from the aquifer.
The sparse data available are primarily from tests for
oil within the study area. Some information is available on
water wells, many of which were originally drilled for oil
tests and then completed as wells. Information is virtually
nonexistent that could be used for determining regional
values for recharge, discharge, transmissivity, storage,
vertical leakage, water use, and water-level fluctuation.
Values of these parameters will be needed for evaluation of
the water supply potential of the Madison aquifer.
Overcoming the data-base deficiencies will require
collection of new data on surface and subsurface hydrologic,
geologic, geophysical, and geochemical features. Analyses
of these data will then be used in predicting the possible
effects of proposed withdrawals on the hydrologic system.
The objectives of a proposed study of Madison aquifer
would be as follows: (Ref. A-2)
107
-------
CANADA
o
00
-POWDER' '
NORTH^DAKOTA
—— ~ "SOUTH DAKOTA
SIOUX
CITY
Figure A-2. Upper Missouri Basin (Source: Ref. A-l).
-------
1. Determine the quantity of water that may be
available from the Madison aquifer.
2. Define chemical and physical properties of the
water.
3. Determine the effects of current developments on
the potentiometric head, storage, recharge and
discharge, springs, streamflow, and pattern of
groundwater flow.
4. Predict the probable hydraulic effects of proposed
withdrawals of water for large-scale developments
at selected rates and locations.
5. Determine the location of wells and the type of
construction and development of deep wells that
would provide optimum yields.
6. Design a network of observation wells and stream
gages to monitor the effects of additional de-
velopments on the hydraulic systems.
It is estimated that 3 million acre-feet of water will
be required on an annual basis for all types of coal de-
velopment in the Upper Missouri River Basin. The major
impact of meeting such a demand would be on river navigation
(Ref. A-l). The normal 8-month season may be shortened and
possibly nonexistent in dry years. Additionally, instream
fisheries may be affected to an undetermined degree. Water
supplied in this manner would have to be transported over
161 km (100 miles) to the coal fields.
At present only one proposal for a coal slurry pipeline
would entail water withdrawal from the Missouri River Basin.
This is the pipeline proposal initiated in late 1973 by
Energy Transportation Systems, Inc. The coal slurry pipe-
line would pump coal from Gillette, Wyoming, to White Bluff,
Arkansas (Ref. A-3). This pipeline would require approxi-
mately 22.7 million m3 (18,400 acre-feet) of water per year
to transport its design load of 22.7 million metric tons (25
million tons) per year. Therefore, less than 2 percent of
the water required for coal development will be dedicated to
coal slurry transport.
109
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Upper Colorado River Basin
The Upper Colorado Basin stretches from the headwaters
of the Colorado River to Lee's Ferry, a point approximately
19 km (12 miles) below Glen Canyon Dam. Average annual
precipitation is as high as 36 cm (8 inches) in lower parts
of the basin. The major coal and oil shale resources, as
well as river systems, are shown in Figure A-3.
Surface water supply in the Upper Colorado River Basin
has ranged from an annual flow of 6.9 billion m3 to 29.6
billion m3 (5.6 million acre-feet to 24.0 million acre-feet)
with an average of about 18.5 billion m3 (15.0 million acre-
feet) (Ref. A-4). Because of the Colorado River Compact,
however, only 7.16 billion m3 (5.8 million acre-feet) of
that water is available for consumption in the basin. Above
Lee's Ferry the current consumption is about 4.57 billion m3
(3.7 million acre-feet). This includes depletion for all
uses including agricultural, municipal, industrial, and
storage.
Table A-l shows supply and demand figures for the Upper
Colorado River Basin. As the table shows, the supply of
water for electrical power and minerals is adequate in
Colorado and Utah but not in Arizona or New Mexico (Ref.
A-5). It is projected that New Mexico will be short by 0.11
billion m3 (90 thousand acre-feet) in the year 2000; some
agricultural allocations, however, could be transferred to
industrial use. On the other hand, Arizona is expected to
be short by 34.1 billion m3 (27.6 thousand acre-feet) per
year of meeting projected demand for the year 2000; Arizona
has no allocation of any kind remaining to meet this demand.
Groundwater could offer a possible supplemental or short-
term source of water. The minimum amount of groundwater in
storage in the upper 30.5 m (100 feet) of saturated hy-
drogeologic units, based on available specific yield data,
ranges from 61.7 to 141.9 billion m3 (50 to 115 million
acre-feet). The average annual recharge in the basin is
estimated at only 4.9 billion m3 (4 million acre-feet)
annually.
At present, two coal slurry pipelines in the planning
stages would withdraw from the Upper Colorado River Basin.
These are the Gulf Interstate-Northwest Pipeline and the
Houston Natural Gas Colorado to Texas system (Ref. A-3).
These two pipelines would require annually about 14.6 million
and 8.1 million m3 (11,800 and 6,600 acre-feet) respectively.
110
-------
MONTANA
) ( MISSOURI RIVER
I r**
COLORADO^ _
I OKLAHOMA
'NEW MEXICO "EXAS "
LEGEND:
WATER SUPPLY
COAL FIELDS
OIL SHALE DEPOSITS
Figure A-3. .Major coal, oil shale, and river systems
in the Upper Colorado Piver Basin.
Ill
-------
Table A-l. ESTIMATED SUPPLY/DEMAND FOR UPPER
COLORADO RIVER WATER IN THE YEAR 2000
(Thousands of acre-feet per year)
Projected Water Requirement
for Energy (Consumptive Use
Electricity
(Coal-fired plants only)
Coal
Oil Shalg
Total
Apparent Water Availability
Electric Power •
Minerals
Argiculture
Other
Total
Ariz.
62
-
-
62
34.1
.3
7.6
8.0
50.0
N. Mex.
120
60
-
180
90.0
17.4
329.0
141.3
577.7
Utah
24
-
18
42
261.8
10.3
660.6
314.0
1,246.7
Colo.
-
-
112
112
108.2
128.3
1,778.2
1,004.7
3,019.4
Total
206
60
130
396
494.1
156.3
2,775.4
1,468.0
4,893.8
Source: ref. A-5.
Convcrnion for metric unit: one acre-ft = 1233.489
m
112
-------
This water usage would, therefore, utilize about 31 percent
of the projected water requirement for coal development or
less than 1 percent of the apparent water availability
(Table A-l).
Lower Colorado River Basin
The Lower Colorado River Basin extends from Lee's Ferry
to the Gulf of California. Annual precipitation in this
area ranges from 10 to 76 cm (4 to 30 inches), and evaporation
averages about 254 cm (100 inches) (Ref. A-6). Water
resources are scarce in Arizona and New Mexico. It is
estimated that no more than 67.9 million m3 (55,000 acre-
feet) remains uncommitted in New Mexico. Nearly all the
water in Arizona is currently committed. Indications are
that the projected water demand for energy in Arizona and
New Mexico is approximately 0.33 billion m3 (269,000 acre-
feet) per year. If this demand is to be met, no additional
demands for municipal, irrigation, or other use could be
placed on this basin (Ref. A-l). Water for energy use might
be obtained by purchase of some Indian water rights. Several
hundred million cubic meters (several hundred thousand acre-
feet) of "perfected rights" are now allocated to various
reservations and are not being used.
The Black Mesa Pipeline is now operating and is with-
drawing groundwater from this basin. The withdrawals are
purchased from Indian Water Rights. An additional coal
slurry pipeline proposal known as the Nevada Power-Utah/
Nevada system is in progress. This pipeline will require
approximately 9.13 million m3 (7,400 acre-feet) per year.
This volume is equal to approximately 2.8 percent of pro-
jected water demand for energy purposes.
Rio Grande Basin
The Rio Grande Basin is the major drainage basin in New
Mexico. The basin extends from the Continental Divide in
the mountains of Colorado to the flat, arid lowlands of
southern New Mexico. Annual precipitation ranges from 20 to
60 cm (8 to 24 inches), and average annual evaporation is
about 254 cm (100 inches) (Ref. A-6). The development of
associated energy resources is generally similar to that
discussed for the Lower Colorado River Basin.
113
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INTERNATIONAL PIPELINE
A coal slurry pipeline currently in the planning stages
is known as the Interprovincial Lakehead System. The pipe-
line would originate in Edmonton Alberta, Canada, and traverse
3389 km (2100 miles) to the northern midwest and eastern
United States. The water withdrawals to maintain this
pipeline at design capacity would be 13.6 million np (11,038
acre-feet) per year. Although this water would be withdrawn
from Canadian sources, the withdrawals could affect down-
stream water resources in the United States.
SALINE GROUNDWATER SUPPLIES
The saline groundwater underlying most parts of the
United States contains at least 1,000 milligrams per liter
(mg/liter) of dissolved solids; this solids content varies
throughout the states, as do the quantities and degree of
accessibility- It is possible that as much as 166,620 km^
(40,000 mi3) of saline groundwater is stored at various
depths in rock aquifers in some parts of the country (Ref.
A-7). Relatively little information is available on the
location of saline groundwater in the west; the little
information that is available appears promising.
Saline groundwater reserves ranging in depth from less
than 150 m (500 feet) to more than 1520 m (5000 feet) are
found in the coal-bearing regions in western North Dakota,
the northwest corner of South Dakota, eastern Montana, and
the northeast corner of Wyoming. The north-central Montana
coal reserve region is underlain with saline water at depths
less than 150 m (500 feet) to more than 300 m (1000 feet).
Saline groundwater is found at depths generally less than
300 m (1000 feet) in the northwest corner of Colorado. The
northeast corner of New Mexico is underlain by saline
groundwater at depths of less than 150 m (500 feet), and
coal regions in northeast Arizona have saline groundwater at
depths of 150-300 m (500 to 1000 feet) (Ref. A-7).
To generalize on yields from large regions can be
misleading, especially with the lack of good data on the
western saline aquifers. Some of the aquifers of interest
in projected major coal-producing areas can be characterized
in this light. The Madison Limestone Aquifer, which underlies
eastern Montana, northeastern Wyoming, and western North and
114
-------
South Dakota, contains water with salinity ranging from 1000
to 100,000 mg/liter, but more typically 1000 to 3000 ing/liter.
The water outputs for individual wells in the Madison Aquifer
are expected to range from large yields of hundreds of
liters per second (thousands of gallons per minute) near the
outcrop to tens of liters per second (hundreds of gallons
per minute) where limestone is deeper and more saline (Ref.
A-7) .
Dakota Sandstone is a saline-water-bearing stratum
capable of producing moderate to large amounts of highly
saline water that has been known to flow under artesian
pressure. It is located in North and South Dakota, Ne-
braska, Kansas, Wyoming, and Colorado. The Coconino Sand-
stone in northern Arizona can yield only moderate amounts of
saline water for industrial purposes. The Redwall Limestone
aquifier of north-central Arizona supports several large
springs in that area. It probably could be used to produce
saline water either from the springs or well fields (Ref. A-
7) .
Although these saline waters have little value for
domestic use, care must be taken in withdrawals, which over
a long period might change the regional flow patterns and
pressure distributions. If saline waters and fresh waters
are not hydrologically isolated, pumping of the saline
strata might cause flow changes in the fresh water aquifer
or even intrusion of fresh water into the salt water. Land
subsidence and contamination of moderately saline groundwater
with more highly saline water from deeper aquifers are also
possible environmental impacts. Therefore, any use of
saline groundwaters should be closely monitored.
11!
-------
REFERENCES - APPENDIX A
A-l. A Western Regional Energy Development Study, Primary
Environmental Impacts, Appendices. Radian Corporation.
Council on Environmental Quality, Washington D.C.
August 1975.
A-2. Plan of Study of the Hydrology of the Madison Limestone
and Associated Rocks in Parts of Montana, Nebraska,
North Dakota, South Dakota, and Wyoming. U.S. Depart
ment of the Interior Geological Survey. Denver,
Colorado. December 1975. 35 p.
A-3. Slurry Pipelines, Innovation in Energy Transportation:
Comments, Questions and Answers. Energy Transportation
Systems, Inc. 1975.
A-4. Report on Water for Energy in the Upper Colorado River
Basin. U.S. Dept. of the Interior, Wastes for Energy
Management Team. 1974.
A-5. U.S. Energy Outlook: Water Availability. National
Petroleum Council. Washington D.C. 1973.
A-6. Chow, Ven Te. Handbook of Applied Hydrology. A
Compendium of Water-Resources Technology. McGraw-Hill.
1964.
A-7. Proceedings of the International Technical Conference
on Solid Liquid. U.S. Energy Research and Development
Administration. Slurry Transport Association. Feb.
1976.
116
-------
APPENDIX B
COMPARISON OF COSTS OF TRANSPORTATION METHODS
A number of recent studies compare costs of trans-
porting coal by rail, slurry pipeline, barge, truck, con-
veyor belt, and pneumatic pipeline. The greatest emphasis
is on railroads and slurry pipelines. This appendix analyzes
results of some of these studies and, in most cases, presents
a comparison of coal transportation rates on the basis of
cents/metric ton-km (cents/ton-mi). The values are derived
from annual operating expenses, which are based on a fixed
capital cost required to put the transportation system into
operation.
Two major studies comparing rail and slurry pipeline
costs are based on the controversial Wyoming to Arkansas
pipeline proposal. The slurry line would be approximately
1610 km (1000 miles) long and would move 22.7 million metric
tons (25 million tons) of coal annually- The two major
studies are 1) the Bechtel Corporation study for Energy
Research and Development Administration and 2) the University
of Illinois study for the National Science Foundation (NSF).
A discussion of these and four other studies follows.
BECHTEL CORPORATION STUDY FOR ERDA
Bechtel Corporation has prepared a coal transportation
cost model that compares pipelines, railroads, and barges.
Transportation rates for each of these modes were developed
and used as inputs for a linear programming model.
Unit Trains
The transportation costs for unit trains, trains
containing approximately 100 cars and capable of handling
9070 kg (10,000 tons), were determined by Bechtel's Metals
Division. These rates, as shown in Table B-l, may vary
depending on such factors as degree of competition, annual
tonnage volume, train and car sizes, type of car, loading
117
-------
and unloading methods, terrain, and track conditions.
Eastern rates are estimated to be about 40 percent higher
and southern territory rates about 25 percent higher than
those in Table B-l. A hyperbolic curve fitted to the data
in Table B-l yielded the following equation:
C = 122.45 D~°'391
where,
C = Unit train rate in 1974 dollars
(mills/metric ton-km) or (mills/ton-mi)
D = Short-line rail distance, miles
For a 1600-km (1000-mile) one-way trip, assuming that
22.7 million metric tons (25 million tons) of coal were
hauled annually, this equation would yield a transportation
rate of 0 . 56
-------
Table B-l. RAIL RATES FOR UNIT TRAINS
WESTERN RAILROADS - 1974
One-way distance, km (miles)
160
320
480
640
800
960
1290
1600
2400
(100)
(200)
(300)
(400)
(500)
(600)
(800)
(1000)
(1500)
Rate,
mills/metric ton-km
(mi 11s/ ton-mile)
13.7 (20)
11.0 (16)
8.9 (13)
8.2 (12)
7.5 (11)
6.9 (10)
6.2 (9)
5.5 (8)
4.8 (7)
Source: Ref. B-!
119
-------
Table B-2. BARGE TRANSPORTATION RATES - 1970
One-way distance,
km(miles)
Rate,
Mills/metric ton-km (mills/ton-mi)
80 (50)
160 (100)
320 (200)
480 (300)
640 (400)
800 (500)
(Source: Ref. B-l]
4.8 (7.0)
3.6 (5.2)
2.9 (4.2)
2.6 (3.8)
2.5 (3.6)
2.4 (3.5)
120
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Slurry Pipelines
In developing cost estimates for new slurry systems,
Bechtel included in the capital costs facilities for slurry
preparation, live storage, dewatering, and pipeline trans-
port; they excluded costs of water supply and cleaning
facilities. Operating costs encompassed the power, labor,
contract maintenance, and supplies required for operation
and maintenance of the included facilities.
Because moving coal by slurry pipeline entails a large
amount of unit operations at the first pump station and
dewatering terminal, costs were segregated into fixed and
variable components. The fixed component covered those
costs dependent upon capacity only; the variable component
was a function of both capacity and length. Curves were
fitted to these data for generation of equations relating
the cost to capacity and an inflation index. Addition of an
inflation index, in this case the GNP implicit price de-
flator index obtainable from the President's Economic
Report for 1973, allowed synthesis of past costs for cor-
relation with earlier data bases. Prediction of future
system costs by application of the overall inflation rate to
this index is also possible.
Cf = 0.73 (GNP) - 10.48/T + 1.69 +
(GNP)/T - 16.84
Cv = 0.015 (GNP) - 0.627/T +
0.0259 (GNP)/T - 0.0415
where
Cf = Fixed unit transport cost (capital
charge plus operating cost), £/ton
Cv = Variable unit transport cost (capital
charge plus operating costs), C/ton-mile
GNP = Gross National Product implicit price deflator
index:
July 1971
July 1972
July 1973
July 1974
141.6
146.1
153.9
(181.4;
projected
121
-------
T = Capacity, million tons delivered coal/yr
Metric conversion: One ton = 0.90718 metric ton
C/ton-mi = 0.685<;/metric ton-km
Differences in elevation of line terminals, in terrain,
and in soil conditions were evaluated for impacts on the
cost relationships. For most cross-country coal slurry
pipelines, none of these factors would affect the projected
costs to a significant extent (all less than + 10 percent).
Economic factors, such as interest on debt and amortization
period, were also checked for impact. Again, these effects
were not significant (+ 10 percent) within the ranges of 7.5
to 12.5 percent interest and 20- to 35-year amortization.
The only factor imposing a substantial effect on unit
costs was the operating load factor. The fixed unit trans-
port costs were multiplied by the following factor for
operating loads less than design rate:
F = 0.7 (LF/100) + 0.3
where LF is the operating load in percent of design rate.
The load effect on the variable unit cost was negligible.
Bechtel noted that their figures were based upon
hypothetical designs and typical coals. Unusual features of
terrain and/or coal types could modify these cost estimates.
The variable unit transport cost for a 1610-km (1000-
mile) pipeline, transporting 22.7 million metric tons (25
million tons) of coal annually, using the above formula,
would be 0.ISC/metric ton-km (0.27£/ton-mi)• Adding the
fixed unit cost of 0.08£/metric ton-km (0.12£/ton mi) gives
a total unit cost for the pipeline of 0.27C/metric ton-km
(0.39C/ton mi). These costs are shown graphically in Figure
B-l.
UNIVERSITY OF ILLINOIS STUDY FOR NSF
Unit Trains
The University of Illinois study is based on computer
modeling of unit train component costs to calculate unit
train shipping costs (Ref. B-2).
The model showed obvious trends, such as 1) higher
rates with increase in construction costs and 2) lower rates
122
-------
3 45678910 20
ANNUAL THROUGHPUT - Millon Tons
30 40 50
IC/ton-mi = 0.685 C/metric ton-km
Figure B-l. Coal transportation costs,
(Source: ref. B-l)
123
-------
with increase in tons hauled per year. Costs not considered
were expenses for strikes and insurance and for overpasses
and crossings. The added costs for road bypasses and cross-
ings will probably be required because in transport at a
rate of 63.5 million metric tons (70 million tons) of coal
per year, a train would pass by a given point every 40
minutes. Costs of overpasses or underpasses, which range
from $400,000 up, are shared by the railroad and highway,
the former usually paying 10 to 20 percent.
The study points out that the use of human resources
may be more or less favorable than capital investment,
depending on the unemployment situation and interest rates.
It also says that, considering track upgrade only, the
shipping rate of 22.7 million metric tons (25 million tons)
of coal per year would pay out about 45 percent of the $60
million annual costs to direct labor. This would mean a $27
million payroll for 1800 jobs at $15,000 a year; at an
inflation rate of 7 percent, cost would double every 10
years. Thus, a large part of the unit train rates would
continually be subjected to this increase.
Another major cost is the capital needed to build a
unit train system. The study estimated that 2060 additional
cars of 93 metric ton (103.5 ton) capacity would be needed
for a system to ship 22.7 million metric tons (25 million
tons) of coal per year; also required would be ninety 2240-
kW (3000-hp) diesel locomotives or thirty 7460-kW (10,000-hp)
gas turbine locomotives, requiring 68,000 metric tons
(75,000 tons) of steel. The double track would require
about 500,000 metric tons (550,000 tons) of steel to last 25
years. The capital required for a unit train system of this
size for 48-km/hr (30-mph) hauling, including only track
upgrade, was estimated at $116.8 million; if starting with
new ties and rails, the estimated cost would be $394.4
million.
Table B-3 presents the University of Illinois summary
of costs and resources needed for unit trains. The Wyoming
to Arkansas route is numbered (5)-(6). The costs are based
on estimates for upgrading an existing railroad to handle
unit trains traveling 80 km/hr (50 mph) loaded. The up-
grading would include new rails and ties.
Coal Slurry Pipelines
The second part of the University's analysis was an
estimation of slurry pipeline costs for shipment over the
124
-------
Table B-3. COSTS AND RESOURCES FOR UNIT TRAINS
(SOURCE: REF. B-3)
(Costs in million dollars; (25X10* tons/year or 22.7X10" metric tons/year.^new rails and
ties; 50 mph (80.5 kmph) loaded and 60 mph (96.5 kmph) unloaded]
Routes (from fig. 1)'
Milesl-way ... 1,200 1,100 900 500 250
(Kilometers 1-way) (1,930) (1,770) (1,450) (804) (402)
Miles total double track . 1 424 1 324 1 124 724 474
(Kilometers total dbl track) (2,290) (2,130) (1,810) (1,160) (762)
Capital costs:
Roadbed... 320.0 298.0 253.0 163.0 107.0
Equipment 90.0 83.0 72.0 50.0 36.0
Total capital costs _ 410.0 381.0 325.0 213.0 143.0
Average fixed charge on debt:
Average rate base 205.0 190.5 162.5 106.5 71.5
Debt Retirement (0.134) .. 27.5 25.5 21.8 14.3 9.6
Federal tax (28 percent)... 7.7 7.1 6.1 4.0 2.7
Depreciation (25 yr) 16.4 15.2 13.0 8.5 5.6
Total average fixed charge on debt. 51.6 47.8 40.9 26.8 17.9
Operating costs:
Fuelcosts 15.2 13.9 11.4 6.3 3.2
Labor costs _ 27.0 23.5 19.8 12.6 8.4
Supplycosts ._ 6.6 5.8 4.9 3.1 2.1
Total operating costs 48.8 42.7 36.1 22.0 13.7
Total annual cost 100.4 90.5 97.0 48.8 31.6
Unit costs:
Dollars per ton 4.02 3.62 3.08 1.95 1.26
(Dollars per metric ton) (4.32) (4.01) (3.40) (2.16) (1.39)
Dollars per ton-mile .0033 .0033 .0034 .0039 .0050
(Dollars per metric ton-km) (.0023) (0.023) (.0024) (.0027) (.0034)
Dollars per 10« Btu-mile1. .206 .206 .142 .162 .213
(Dollars/ion Joule-km) (.122) (.122) (.084) (.096) (.126)
Energy requirements:
Locomotive (horsepower) 530,000 450,000 417,000 245,000 175,000
Million barrels fuel. 1.80 1.65 1.30 0.75 .40
(Percent energy delivered) (2.64) (2.27) (1.54) (0.79) (0.35)
Steel required for 25 yr in tons
FoMocomotive ' -- 75,000 70,000 60, OCC 40,000 25,000
(68000) (63500) (54,500) (36,000) (23,000)
For rails 550000 510000 435,000 280,000 185,000
" (500,000) (460,000) (395,000) (254,000) (170,000)
EmPCap7«|lper worker - 0.227 0.243 0.246 0.254 0.260
Number of )obs (at $15,000 per ~ ~ ~ ~~
Jobs in rVif andtrain" production...-- 310 290 245 160 9u_
Total jobs - zTuO U60 17565 UOO 650~"
' (5H10) is Wyoming to Chicago- (7H8) is Colorado to Texas; (5M6) is Wyoming to Arkansas; (9H8) is Illinois to
Texas- (9M6) is mi"0'3 to Arkansas; (9H10) is Illinois to Chicago.
' 12,000 Btu Illinois coal and 8,000 Btu western coal.
125
-------
same routes. Table B-4 summarizes capital and operating
costs of a slurry pipeline in comparison with unit train
costs.
In comparison of a new slurry pipeline with the best
upgraded railroad, the slurry pipeline costs 0.47C/metric
ton (0.69
-------
Table B-4.
COSTS OF SLURRY PIPELINE IN COMPARISON TO RAIL
(Costs in Million Dollars)
CAPITAL COSTS:~
A. Preparation equipment and wells
Tons/year
o. Piping and Installation
Electrical trans.issIon
(1 pumping atatlon/90 nlles)
L. Separation plant and water disposal
TOTAL CAPITAL COSTS
ANNUAL COSTS:
Debt Retirement
Rate base (13.11)
Federal Tax (3.31)
Depreciation (25 years)
(State Tax. 2Z on Inv.)
Total Debt Retirement
B. Operating Labor Direct (no. of men
Administrative
C. Material and maintenance supplies
Total of Q and C
D. Power (Installed horsepower)
E. Water (acre/foot/yeaj)
TOTAL ANNUAL COSTS
(Total annual costs w/o state tax)
a. S/ton Including state tax
D. S/ton excluding state tax
... S/109 Btu-mlle Including state t.
a. S/10* Btu-mlle excluding state t
«. c/lon-mlle Including state tax
f. c/ton-mlle excluding state tax
nold-up In Pipe ID tons at 3.5 nph
Comparison to Rail In cents/ton-alle
Mew road. 50-60/30-60 mph
Hew rail. 50-60/30-60 mph
Track upgrading, 30-60 mph
Tralo* on tn« road, 50-6073O*60 mph
Total locomotl»« hor»«pw«r:
50-60 mph
30-60 mph
C«it »/109 Btu-mlla. nev rail 50-60 mph
Colorado -
Texas* (7)-(8)
Illinois -
Chicago (9)-(10)
llllnolB -
Arkansas (9)-(6)
Illinois -
exas* (9)-(8)
iO
h
5x10
18"D(273ml)
60
90
25xl06
10.1
2.5
6.0
(2.0)
21.6
1.6 (84
0.8
1 (21.000)
I
0,5 (3,000)
26.5
(24.5)
5.30
4.69
1.21
1.07
1.94
1.72
1,034
25x10
38"D(1200ml)
1.133
1.133
90
25xl06
38"D(300«1)
261
50
401
7.22
6.40
0.43
0.39
0.69
0.62
1.15/1.12
0. 33/0.31
0.19
13/16
450,000
250,000
v.ll
8.12
0.48
0.43
0.76
0.68
1.14/1.13
0.33/0.32
0.20
13/16
530,000
300,000
25x10
38"D(700ml)
609
50
749
2.83
2.51
0. 39
0.35
0.95
0.84
1.78/1.13
0.50/0.49
0.30
3/5
175,000
90,000
3.33
4.70
0.32
u.28
0. 76
0.68
1.19/1.17
0.34/0.32
0.20
10/1*
420,OOO
240,000
Difficult Terrain
(Source: R*f. B-))
version: S/ton - 0.90718 $/»etrlc ton
5/10 Btu-til - 0.00247 S/10 g-cal-
c/ton-ml . 0.685c/netrlc ton-ka
nph - 1.609 Whr
127
-------
Illinois coal fields to a plant site on the lower Missis-
sippi would be about 800 km (500 miles). A 1450-km (900-
mile) route is equivalent to the distance between east
Kentucky and the Dallas-Fort Worth area; 2400 km (1500
miles) is equivalent to the distances between Wyoming and
the lower Mississippi and Gulf Coast areas.
Ebasco used levelized cost figures calculated on an 8.0
percent discount rate for the rail and rail-barge system and
an 11,4 percent rate for the coal slurry lines. They also
used a 30-year amortization period and 6 percent annual
escalated rate.
In addition, the following basic assumptions were made
in computing the costs for each system.
a) Railroad and Rail and Barge Systems
1. Existing rail lines were available to deliver
coal from the mines to the plant or the
barges.
2. Unit train and barge rates for such large
volume movements were not available from a
published tariff schedule. The rates used in
this study represent those that Ebasco
believed could be negotiated with the car-
riers and are based on other known unit train
and barge freight rates.
3. Hopper cars costs were obtained from a
manufacturer. Maintenance costs were based
on published data on cars in unit train
service.
4. Based on the long-term trend, rail freight
rates and barge rates were assumed to es-
calate at the rate of 6 percent per year, as
were car maintenance costs.
b) Coal Slurry Pipelines
1. Ebasco estimated investment costs in detail
for a specific case and then adjusted, on an
order-of-magnitude basis, for the other
alternatives.
128
-------
2. Fixed charges were taken at the rate of 14
percent, based on 80 percent debt, 20 percent
equity financing, i.e., nonutility-type
financing.
3. Energy costs were based on actual utility
rates. For example, energy costs for the
2400-km (1500-mile) line included preparation
plant energy costs based on a western utility
company's rates.
4. Material costs were escalated for 1980
initial operation at 6 percent per year;
labor costs were escalated at 8 percent per
year.
Transportation Costs
Transportation costs include investment, fixed charges,
and annual operating and maintenance costs. In the case of
rail or rail and barge transportation, the freight charges
remain the major component, with relatively small amounts
for investment and maintenance.
The rail freight rates used in the study and shown in
Table B-5 are based on mid-1975 conditions and utility-owned
coal cars. The rail-barge rates, calculated on the same
basis, are shown in Table B-6.
Table B-5. RAIL FREIGHT RATES - 1975
Distance, miles
500
900
1500
Freight rate,
5.50
8.50
13.50
$/ton (mills/ ton-mile)
(11.00)
( 9.45)
( 9.00)
[Source: Ref. B-4)
Metric conversion:
1 mile = 1.609 km
$/ton = 0.90718 $/metric ton
mills/ton-mi = 0.685 mill/metric
ton-km
129
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Table B-6. RAIL-CAR FREIGHT RATES - 1975
Distance, miles
500 (100 rail -
400 barge)
900 (300 rail -
600 barge)
1500 (1000 rail -
500 barge)
Freight rate, $/ton (mills/ton-mile)
Rail
2.20 (22.00)
4.30 (14.32)
9.50 (9.50)
Barge
1.80 (4.50)
2.70 (4.50)
2.20 (4.40)
Total
4.00 (8.00)
7.00 (7.79)
11.70 (7.79)
(Source: Ref. B-4)
Metric conversion: 1 mile = 1.609 km
$/ton = 0.90718 $/metric ton
Mills/ton-mile = 0.685 mill/metric ton-km
Ebasco believes that the rates shown are about what
would be arrived at in negotiations with carriers. These
rates were escalated using the long-term trend of 6.0
percent per year, resulting in the levelized rates shown in
Tables B-7 and B-8.
Table B-7. LEVELIZED RAIL FREIGHT RATES - 1980
Distance, miles
500
900
1500
All-rail freight rate, $/ton
(mil Is/ ton-mile)
15.82
24.47
38.81
(31.64)
(27.19)
(25.87)
(Source: Ref. B-4)
Metric conversion: 1 mile =; 1.609 km
$/ton = 0.90718 $/metric ton
Mills/ton-mi = 0.685 mill/metric ton-km
130
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Table B-8. LEVELIZED RAIL-BARGE RATES - 1980
Distance, miles
500
900
1500
Rail and barge rate, $/ton
(mi 11s/ ton-mile)
11.50
20.15
33.65
(23.00)
(22.39)
(22.43)
(Source: Ref. B-4)
Metric conversion:
1 mile = 1.609 km
$/ton = 0.90718 $/metric ton
Mills/ton-mi = 0.685 mill/metric-ton-km
In the case of the capital-intensive pipelines, the
major component of the annual costs are the fixed charges,
operation and maintenance being relatively small. Fixed
charges for the pipeline are about 73 percent of the annual
costs; the balance is operating and maintenance costs. With
73 percent of their annual costs fixed, the coal pipelines
are inflation resistant, only a small component of the
annual costs being subject to escalation forces. Therefore,
in any comparative evaluation with an alternative that is
owning and operating intensive, the capital-intensive
alternative is the more attractive, provided the state
public service commission responds to requests for rate
adjustment on a timely basis.
Pipeline transportation costs are presented in Table
B-9. Table B-10 indicates the portion of the annual costs
that Ebasco estimates are subject to escalation factors for
each transportation system.
131
-------
UJ
Table B-9. PIPELINE TRANSPORTATION COSTS FIGURES FOR
1980 INITIAL OPERATING DATE
Generation, MW
1,600
1,600
1,600
3,200
3,200
3,200
6,400
6,400
6,4CO
9,000
9,000
9,000
Coal delivery,
tons per year
4,500,000
4,500,000
4,500,000
9,000, 000
9,000,000
9,000,000
18,000,000
18,000, 000
18, 000, 000
25,000,000
25, 000, 000
25,000,000
Distance,
miles
500
500
1,500
500
900
1,500
500
900
1,500
500
900
1,500
Pipe diameter,
inches
18
18
18
24
24
24
34
34
34
40
40
40
Investment,
$1000
245,000
520,000
725,000
490,000
710,000
1,050,000
1,065,000
1,575,000
2,440,000
1,500,000
2,090,000
2,660,000
Levelized
annual cost,
$1000
47,070
99,900
139,290
94,140
136,400
201,720
204,610
302,590
468,770
288,190
401,530
511,030
Trans-
portation
cost,
cents
ton-mile
2.09
2.45
2.06
2.09
1.68
1.49
2.27
1.87
1.74
2.31
1.78
1.36
(Source: Ref. C-4)
Metric conversion: 1 ton = 0.90718 metric tons
1 mile = 1.609 km
1 inch = 2.54 cm
C/ton-mi = 0.685
-------
Table B-10. ESCALATION FACTORS FOR ANNUAL COSTS
System
All-rail
Rail-barge
Coal pipelines
Approximate percent of annual
costs subject to escalation
98.5
99.0
27.1
(Source: Ref. B-4)
Table B-ll is a breakdown of the levelized annual
owning and operating costs of the alternatives studied based
on a 1980 initial operating date. Table B-12 tabulates the
alternative costs based on differentials over the lowest
cost alternative. The chart shows that coal pipelines are
the most economical system in almost all cases. Rail and
barge transportation systems are the next most economical
alternative.
Conclusions
Ebasco came to the following conclusions:
1. In all but a few cases, pipeline transportation systems
are the lowest-cost mode of energy transportation,
followed by the rail-barge systems, as defined in the
study. Coal pipelines are even more attractive if rail
facilities do not serve the area under consideration.
2. Barge and rail transportation systems are worthy of
consideration if (a) navigable waters for barge move-
ments are available, and (b) the tonnage, distances,
and split between rail and barge hauling distances are
in the "right" proportions.
3. Coal pipelines are more inflation-proof than rail or
rail and barge modes of transportation because of the
low, overall operating and maintenance costs associated
with pipe slurry. This should be weighed against the
high operating cost of the rail and barge systems when
selecting the transportation mode for a new coal-fired
power plant.
4. If coal pipelines are to be viable, the right of
eminent domain must be available to the user. In order
133
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Table B-ll. ANNUAL LEVELIZED UTILITY OWNING AND OPERATING COSTS
THOUSANDS OF DOLLARS
Distance, Miles
Capacity, MW
Railroad
Fixed charges
Operating
Total
Rail-Earge
Fixed charges
Operating
Total
Pioeline
Fixed charges
Operating
Total
500
1,600
1,400
73,520
74,920
500
52,380
52,880
34,300
12,769
47,069
500
3,200
2,800
147,250
150,050
900
104,550
105,450
68, 600
25,533
94,138
500
6,400
5,600
294,500
300,100
1,800
500
9,000
7,800
413,700
421,500
2,500
I
209,100
210,900
149,100
55, 507
204,607
290,390
292,890
210,000
73,190
288,190
900
1,600
1,700
114,760
116,460
800
92,360
93,160
72,800
27,101
99,901
900
3,200
3,500
228,890
232,390
1,700
184,510
186,210
99,400
37,003
136,402
900
6,400
6,900
458,000
464,900
3,300
369,010
372,310
220,500
82,085
302,585
900
9,000
9,700
637,950
647,650
4,500
512,320
516,820
292,600
108,926
401,526
1,500
1,600
2,100
181,430
183,530
1,800
156,490
158,290
101,500
37,785
139,285
1,500
3,200
4,200
362,850
367,050
3,600
312,908
316,580
147,000
54,723
201,723
1,500
6,400
8,400
725,710
734,110
7,300
625,960
633,260
341,600
127,167
468,767
1,500
9,000
11,700
1,007,970
1,019,670
9,900
866,950
876,850
372,400
133,633
511,033
Metric conversio;
(Source: Ref. C-
i: 1 mile = 1.609 km
•4)
(Source: Ref. B-4)
-------
Table B-12. DIFFERENTIAL ANNUAL OWNING AND OPERATING COSTS
MILLIONS OF DOLLARS
Distance, Miles
Generation, MN
Annual costs
Railroad
Rail and Bnrge
Pipeline
Differential
Railroad
Rail and Barge
Pipeline
500
1,600
74. 92
52.88
47.07
27.85
5.81
Base
500
3, 200
150.05
105.45
94.14
55.91
11.31
Ease
500
6,400
300.10
210.90
204.61
95.49
fa. 29
Base
500
9,000
421. 50
292.80
238.19
33.31
4. 61
Base
900
1,600
116.46
93.16
99.90
23.30
Base
6.74
900
3,200
232.39
186.21
136.40
95.99
49.81
Base
900
6,400
414.90
372.31
302.59
162.31
69.72
Base
900
9,000
647.65
516.82
401.53
246.12
115.29
Base
1,500
1,600
183.53
158.29
137.27
44.24
19.00
Base
1,500
3,200
367.05
316.58
201.72
165.33
114.36
Base
1,500
6,400
734.11
622.26
468.77
265.34
164.49
Base
1,500
9,000
019.67
876.85
511.03
508.64
365.82
Base
Metric conversion: One mile = 1.609 km
(Source: Ref. C-4)
(Source Ref. B-4)
-------
to accomplish this, utilities must pursue this with
their legislative leaders well ahead of time, since the
subject is politically volatile.
UPPER MIDWEST COUNCIL STUDY
In April 1975, the Upper Midwest Council published a
report dealing with conflicts and options in decision
making. The decisions and policies considered dealt mainly
with the factors affecting the transport of coal (or elec-
trical energy).
In one section, the council compares costs and energy
requirements. To illustrate some of the cost parameters,
they created a hypothetical situation for comparing three
modes of energy transport: railroad, slurry pipeline, and
transmission lines. Coverage is restricted to the railroads
and slurry pipelines. The model factors established that
10.9 million metric tons (12 million tons) per year were to
be transported 1126 km (700 miles) to a 3 million kilowatt
power plant. The following items were considered and values
assigned (Ref. B-5).
CAPITAL INVESTMENT (1975 DOLLARS)
RAILROAD: Initially need 65 engines and
1573 coal cars. All would be replaced at the
15-year mark. Figure includes cost of initial
equipment in 1975 plus dollars needed today to
replace all equipment in 15 years discounted
at 7% interest.3 $86,900,000
SLURRY: Includes construction and materials
for coal preparation facility, a 96.5 cm (38-inch)
pipeline and associated pumping and emergency
storage systems, de-watering facility and
right-of-way acquisition. Also includes
cost of replacement materials over 30-year
period. $505,000,000
ANNUAL VOLUMES OF VARIOUS FUELS CONSUMED FOR TRANSPORTATION
RAILROADi Liters (gallons) of diesel fuel at
9.3 x 10b g-cal/1 (140,000 Btu/gallon) plus
energy used in refining - 300,000 g-cal/1
(4500 Btu's/gallon) of diesel oil produced. 54,125,000 liters
(14,300,000 gal.)
136
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SLURRY: Metric tons (tons) of Sarpy
Creek coal at 4.67 x 109 g-cal/metric ton
(16,800,000 Btu/ton) times 2.85 due to
electric generating plant efficiency of
only 35 percent.
ANNUAL ENERGY LOSSES
RAILROAD: 43,150 g-cal/metric ton-km
(250 Btu/ton-mile), including empty return
of cars.6
SLURRY: 169,000 g-cal/metric ton-km (980
Btu/ton-mile), including energy used in coal
preparation and dewatering.l
OTHER RESOURCE REQUIREMENTS
RAILROAD: Initial system development and
component replacement over 30-year period.
SLURRY: Initial system development and
component replacement over 30-year
period.
1,334,000
metric tons
(1,470,000 tons)
4.86 x 10J1 g-cal
(1.93 x 10 Btu)
2.07 x 10^ g-cal
(8.23 x 10 Btu)
101,650 metric
tons
(112,050 tons)
steel
275,800 metric
ton
(304,000 tons)
steel
TRANSPORTATION COSTS TO CONSUMERS - 1975
RAILROAD: Based upon 1975 tariff quote from
Burlington Northern to Becker, Minnesota.
Tariff quoted was $4.99 per ton.
SLURRY: Based upon estimates developed for
the proposed Wyoming-Arkansas coal slurry
by Bechtel, Inc.
2.9 mills/kWh
4.4 mills/kWh
137
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Using their data, the cost of transporting coal by rail
would be 0.49^/metric ton-km (0.71C/ton-mi) and 0.74£/metric
ton-km (1.08£/ton-mi) by slurry line. An additional long-
term cost consideration was that about 95 percent of the
steel used by the railroads can be recycled when removed
from use, whereas buried pipelines are hardly ever removed
from the ground because the cost of removal is greater than
the price of scrap steel.
The report stated that any decision to allow construc-
tion of pipeline slurry systems should be delayed until
questions relating to economic impact on the rail industry
are answered. The final consensus was expressed in general
terms and did not favor one over the other. They believe
that there is no single, simple answer to whether a railroad
or a pipeline slurry is the best way to move energy -
Overall, in relation to broad energy transportation re-
quirements, either of the two systems is viable technolog-
ically and could be made feasible economically.
They state that when a particular utility is consid-
ering which transportation system is best for its specific
needs, clear-cut choices would arise and a "best" system
could be chosen for that particular situation.
COSTS PUBLISHED FROM OTHER SOURCES
Energy Transportation Systems, Inc. (ETSI), (1975)
which is 40 percent owned by Bechtel, has presented a cost
comparison for coal transport which is virtually identical
to the recent Bechtel study. Cost estimates by members of
ETSI have also appeared in Chemical Engineering (1971), and
the "Oil and Gas Journal" (1973). The Chemical Engineering
and the Oil and Gas Journal, costs are presented in Tables
B-13 and B-14, respectively, and indicate clearly that
trucks and conveyor belts are not competitive with railroads
and slurry pipelines over long distance. However, trucks
and conveyors have been proven over short distances and for
special situations.
CONCLUSIONS
All of the studies discussed indicate that long-distance
slurry pipeline and rail shipments of coal are both feasible
in a comparative cost sense. Thus, both are viable candidates,
especially for shipment of western coal where new mines will
typically support large-volume movements. Although about 15
138
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Table B-13. COST COMPARISONS FOR SOLID VOLUMES OF
1.8 TO 5.4 MM METRIC TONS (2 MILLION TO 6 MILLION TONS) PER YEAR
Carrier
Transport costs,
cents per metric
ton-km (ton-mile)
Conditions
Slurry pipeline
Rail
Truck
Conveyor belt
.2 to .5 (0.3 to 0.7)
.3 to .6 (.4 to .9)
3.4 to 5.5 (5.0 to 8.0)
1.4 to 4.1 (2.0 to 6.0)
Over 80 km (50 miles)
Unit train, over 645 km (400 miles)
One-way haul, empty return
Less than 24 km (15 miles)
<£>
Source: (Ref B-6)
Table B-14. TRANSPORT COSTS FOR COAL BY SLURRY LINE AND RAILROAD
Fuel
Coal slurry
Railroads (0.6 cent per
ton-mile plus 10
percent greater distance)
(Cents/MM Btu/day
100 miles)
(2.4)
(4.0)
Transportation costs are presented for various 1-trillion-Btu-per-day movements
over a distance of 1,000 miles.
Data extracted from ref. B-7.
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percent of the coal tonnage moves on inland and coastal
waterways, this traffic is limited to that originating from
mines adjacent to waterways. (Ref. B-8.) The metric ton-km
(ton-mile) cost of water traffic is typically lower than
rail costs for the same service. One of the reasons is that
barge lines are not under the jurisdiction of the Interstate
Commerce Commission (ICC), as are the railroads and truckers.
In addition, the barge lines "right-of-way" is maintained
and improved at no direct cost to them, but by taxes through
the U.S. Corps of Engineers.
If the ETSI/Bechtel comparisons prove to be realistic,
pipelines can be expected for very large shipments, with the
railroads continuing to dominate the field for large, but
not huge volumes. This, of course, depends on granting of
the right of eminent domain to slurry pipeline companies,
and on availability of adequate water supplies, especially
in the western states, for pipeline development.
If the rationale of the University of Illinois study
were to be followed, pipelines could be expected in areas
where no existing railroads are now operating and terrain is
unfavorable for new rail lines, a situation most likely to
arise in the semi-arid western states. In most cases,
however, the railroad would continue to dominate coal
transportation.
140
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REFERENCES - APPENDIX B
B-l Organizational Conflict of Interest in Government
Contracting. Hearings before the Subcommittee on
Energy Research and Water Resources. Washington, 1976.
B-2 Coal Slurry Pipeline Legislation. Hearings before the
Committee on Interior and Insular Affairs. House of
Representatives. Washington, 1975.
B-3 Rieber, Michael, and Shao Lee Soo. The Coal Future:
Economic and Technological Analysis of Initiatives and
Innovations to Secure Fuel Supply Independence.
University of Illinois at Urbana-Champaign. May 1975.
B-4 Banks, A. J., and R. B. Leemans. Energy Transporta-
tion. Ebasco Services, Inc. American Power Conference,
Chicago, Illnois. April 1976.
B-5 Murphy, Michael J. Northern Great Plains Coal:
Conflicts and Options in Decision Making. Upper
Midwest Council. April 1976.
B-6 Aude, T. C. Slurry Piping System: Trans, Design-
Method, Guidelines. Chemical Engineering. June 28,
1971.
B-7 Wasp, E. J. Slurry Pipeline . . . Energy Movers of the
Future. Oil and Gas Journal. December 24, 1973.
B-8 Bureau of Mines Circular No. 8690. Long Distance Coal
Transport: Unit Trains of Slurry Pipeline, United
States Department of the Interior (1975).
141
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
REPORT NO.
EPA-600/7-78-081
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Environmental Assessment of Coal Transportation
5. REPORT DATE
May 1978 issuing elate
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Michael F. Szabo
8. PERFORMING ORGANIZATION REPORT
9. PERFORMING ORGANIZATION NAME AND ADDRESS
PEDCo Environmental, Inc.
11499 Chester Road
Cincinnati, Ohio 45246
10. PROGRAM ELEMENT NO.
EHE623
11. CONTRACT/GRANT NO.
Contract No. 68-02-1321
Task No. 40
12. SPONSORING AGENCY NAME AND ADDRESS
Industrial Environmental Research Lab. Cincinnati, OH
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
13. TYPE OF REPORT AND PERIOD COVERED
Final 2/76-12/76
14. SPONSORING AGENCY CODE
EPA/600/12
15. SUPPLEMENTARY NOTES
16. ABSTRACT
As a result of an increase in U.S. coal production to help achieve energy
independence, much attention is being focused on regional-scale transportion of
coal in volumes projected to reach 1.32 billion metric tons (1.2 billion tons) in
1985. Most transportation studies to date have centered on economics. Equally
important, however, are the possible environmental impacts due to both normal
operation and catastrophic events associated with preparation and transportation
of coal. Many of the environmental impacts can be lessened by improvements in
control technology; most of these impacts are not critical in terms of health and
welfare; some, however, such as toxic properties of effluents from coal preparation
plants, storage piles, and slurry lines, need further characterization. In addition,
uses of energy associated with the transport modes should receive consideration in
planning of coal transportation systems.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b. IDENTIFIERS/OPEN ENDEDTERMS
COSATI Field/Group
Barges
Coal Mining
Conveyers
Railroads
Trucks
Transportation
Air Quality
Coal Slurry Pipelines
Coal Transportation
Assessment
Water Quality
43E
43G
85B
13, DISTRIBUTION STATEMENT
Release to the Public
19. SECURITY CLASS (This Report)
ITnr.1agc.-i f-( PH
21. NO. OF PAGES
20. SECURITY CLASS (This page)
22. PRICE
EPA Form 2220-1 (9-73)
142
ft U S GOVERNMENTPfflNTWGOFFICE: 1978— 757-140/1313
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