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Terms
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Description
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Accessed
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Coal
deposits that have been prepared for mining by construction
of portals, shafts, slopes, drifts, and haulage ways; by
removal of overburden; or by partial mining (see also virgin
coal).
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Accessibility
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In
reference to coal resources (core meaning), the absence of
land use restrictions and the assumption that ownership or
leaseholds will be obtainable for mining (see also
environmental restrictions, industrial restrictions). Many
technological restrictions were traditionally applied as
demonstrated reserve base criteria, but (extended meaning)
with the advent of available resource studies, specific
technologic restrictions may be incorporated in
accessibility factors (see also restricted resources).
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Accessibility
Factor
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The
estimated ratio of accessible reserve base to the
demonstrated reserve base or of accessible resources to
identified resources.
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Accessible
Reserve Base
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The
portion of the demonstrated reserve base estimated by EIA to
be accessible, determined by application of one or more
accessibility factors within an area. An accessible reserve
base may be referred to as accessible resources because it
is a subset of accessible resources and is usually part of a
single resource study.
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Accessible
Resources
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The
portion of identified resources estimated to be accessible,
determined by application of one or more accessibility
factors within an area.
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Acid Deposition
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The
transfer of acids or acid-forming substances from the
atmosphere to the earth's surface. Referred to as wet
deposition when the transfer occurs through precipitation
(rain, snow, fog); and dry deposition when the transfer
occurs through other processes such as absorption,
impaction, sedimentation, and chemical reaction.
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Acid sensitive
Environments
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Environments,
which can be easily damaged by acid deposition. Some
environments have natural buffering capabilities that allow
them to neutralize significant amounts of acid deposition.
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Agglomerating
Character
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Agglomeration
describes the caking properties of coal. Agglomerating
character is determined by examination and testing of the
residue when a small powdered sample is heated to 950
degrees centigrade under specified conditions. If the sample
is "agglomerating," the residue will be coherent,
show swelling or cell structure, and be capable of
supporting a 500-gram weight without pulverizing.
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Agglomeration
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A
family of processes that can be used to concentrate valuable
minerals (including coal) based on their adhesive
properties.
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American
Indian Coal Lease
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A
lease granted to a mining company to produce coal from
American Indian lands in exchange for royalties and other
revenues; obtained by direct negotiation with Indian tribal
authorities, but subject to approval and administration by
the U.S. Department of the Interior.
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Anthracite
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Coal
of the highest rank; it is almost pure carbon and is used
mainly for home heating and cooking in some developing
countries industrial purposes.
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Appalachian
Region:
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See
Coal-Producing Regions.
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Area
(Surface) Mining
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A
method used on flat terrain to recover coal by mining long
cuts or pits successively. The material excavated from the
cut being mined is deposited in the cut previously mined.
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Ash
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Impurities
consisting of silica, iron, alumina, and other incombustible
matter that are contained in coal. Ash increases the weight
of coal, adds to the cost of handling, and can affect the
burning characteristics. Ash content is measured as a
percent by weight of coal on an "as received" or a
"dry" (moisture-free) basis.
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As-Received
Condition or As-Received Basis
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Represents
an analysis of a sample as received at a laboratory.
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Auger
Mine
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A
surface mine where coal is recovered through the use of a
large-diameter drill driven into a coalbed in a hillside. It
usually follows contour surface mining, particularly when
the overburden is too costly to excavate.
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Availability
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In
reference to coal resources, the absence of land-use or
environmental restrictions and technological restrictions.
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Available
Resources
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In
U.S. Geological Survey studies, the quantity of remaining
identified resources available for development and potential
extraction at the time of determination after adjusting for
geologic considerations, land-use restrictions, and/or
technological restrictions (see also accessible reserve
base).
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Average
Annual Percent Change
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Where:
V0 = the value for the base period.
V= the value for the N period.
n = the number of periods.
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Average
Daily Production
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The
ratio of the total production at a mining operation to the
total number of production days worked at the operation.
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Average
Length of a Shift
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The
arithmetic mean number of hours worked during a production
shift. Overtime is included if usually worked during the
year.
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Average
Mine Price
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The
ratio of the total value of the coal produced at the mine to
the total production tonnage. (See F.O.B. mine price.)
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Average
Number of Employees
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That
means number of employees working each day at a mining
operation. Includes maintenance, office, as well as
production-related employees.
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Average
Number of Employees per Shift
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The
arithmetic mean number of employees working during a shift.
Includes all employees except office workers. (See direct
labor hours.)
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Average
Number of Miners Working Daily
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The
arithmetic mean number of miners working each day at a
mining operation. Includes maintenance as well as production
work performed.
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Average
Number of Shifts per Day
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The
arithmetic mean number of shifts each day at a mining
operation. Includes maintenance as well as production
shifts.
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Average
Open Market Sales Price
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The
ratio of the total value of the open market sales of coal
produced at the mine to the total open market sales tonnage.
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Average
Production per Miner per Day
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The
product of the average production per miner per hour at a
mining operation and the average length of a shift at the
operation.
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Average
Production per Miner per Hour
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The
ratio of total production at a mining operation to the total
direct labor hours worked at the operation.
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Average
Production per Miner per Shift
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Calculated
by multiplying average production per miner per hour by the
average length of a miner shift.
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Average
Quality of Coal
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Refers
to individual measurements such as heat value, fixed carbon,
moisture, ash, sulfur, major, minor, and trace elements,
coking properties, petrologic properties, and particular
organic constituents. The individual quality elements may be
aggregated in various ways to classify coal for such special
purposes as metallurgical, gas, petrochemical, and blending
usages.
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Average
Recovery Percentage
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Average
recovery percentage represents the percentage of coal that
can be recovered from coal reserves at reporting mines,
averaged for all mines in the reported geographic area.
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Barge Loader
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A port
facility where coal barges are loaded.
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Bed,
Coalbed
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All
the coal and partings lying between a roof and floor.
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Bench
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A
subdivision and (or) layer of a coal bed separated from
other layers by partings of non-coal rock.
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Bituminous
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an
intermediate ranked coal between anthracite and
sub-bituminous coal. It has a high carbon content and is low
in moisture content. Bituminous coal can be used for both
steel making and power generation. Low and medium volatile
bituminous coals are ranked by their carbon content, while
high volatile bituminous coals are ranked by their heating
value.
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Bituminous
Coal
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A
dense coal, usually black, sometimes dark brown, often with
well-defined bands of bright and dull material, used
primarily as fuel in steam-electric power generation, with
substantial quantities also used for heat and power
applications in manufacturing and to make coke. Bituminous
coal is the most abundant coal in active U.S. mining
regions. Its moisture content usually is less than 20
percent. The heat content of bituminous coal ranges from 21
to 30 million Btu per ton on a moist, mineral-matter-free
basis. The heat content of bituminous coal consumed in the
United States averages 24 million Btu per ton, on the
as-received basis (i.e., containing both inherent moisture
and mineral matter).
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Boiler
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A tank
in which water is heated or steam is generated.
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Brand
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The name
given to a particular coal product. Each brand has its
unique specification.
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Breaker
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A
machine that combines coal crushing and screening. Normally
consists of a rotating drum in which coal is broken by
gravity impact against the walls of the drum.
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Breeze
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The
fine screenings from crushed coke. Usually breeze will pass
through a 1/2-inch or 3/4-inch screen opening. It is most
often used as a fuel source in the process of agglomerating
iron ore.
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Btu
(British thermal unit)
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The
amount of heat needed to raise the temperature of 1 pound of
water by 1 degree Fahrenheit. The Btu is a convenient
measure by which to compare the energy content of various
fuels.
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Carbon
Dioxide
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A colorless, odorless, non-toxic
radiative gas that is essential to plant and animal life. It
is also emitted as a result of burning organic materials,
including fossil fuels.
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Cannel
Coal
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A
compact, tough variety of coal, originating from organic
spore residues, that is non-caking, contains a high
percentage of volatile matter, ignites easily, and burns
with a luminous smoky flame.
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Capacity
Utilization
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Capacity
utilization is computed by productive capacity and
multiplying by 100.
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Captive
Coal
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Coal
produced and consumed by the mine operator, a subsidiary, or
parent company (for example, steel companies and electric
utilities).
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Carbon
Dioxide (CO2)
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A
colorless, odorless, incombustible gas formed during
combustion in fossil-fuel electric generation plants.
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Census
Divisions
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The
nine geographic divisions of the United States established
by the Bureau of the Census, U.S. Department of Commerce for
statistical analysis. The boundaries of Census divisions
coincide with State boundaries. In some cases, the Pacific
Division is subdivided into the Pacific Contiguous and
Pacific Noncontiguous areas.
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Central
Appalachian Region
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See
Coal-Producing Regions.
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CFR
or C&F
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Cost and
freight. The word cost signifies the price of the goods as
loaded and to which is added the freight to get the goods to
the destination. The term is used with the name of the
destination port, eg. CFR Hamburg.
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Charcoal
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The residue, primarily carbon,
from the partial combustion of wood or other organic matter.
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Chatterer
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A person
or corporation who hires a vessel for the carriage of goods
(either a time charter or voyage charter, or leases the
vessel for their own management and control (a
bareboat/demise charter).
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CIF
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Cost,
insurance and freight. Basically the same as C&F but the
seller must also procure insurance against the risk of loss
or damage during the voyage. The seller contracts with the
insurer, pays the insurance premium, and then includes this
in the price of the goods.
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Clean-Coal
Technologies
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Technologies that allow coal-based
power or electricity generation to have improved
environmental performance, through decreased emissions.
These technologies decrease emissions by using coal in a
more efficient and cost-effective manner.
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Climate
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the long-term / overall weather of an area. Climate therefore, is the
cumulative grouping of separate weather patterns. (see
weather)
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Coal
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A fossil fuel composed mostly of carbon, with traces of hydrogen,
nitrogen, sulphur and other elements.
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Coal
Carbonized
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The
amount of coal decomposed into solid coke and gaseous
products by heating in a coke oven in a limited air supply
or in the absence of air.
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Coal
(coke)
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See
Coke (coal).
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Coal Desulphurization
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Removal of sulphur from coal or
coal gas.
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Coal
Exports
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Amount
of U.S. coal shipped to foreign destinations, as reported in
the U.S. Department of Commerce, Bureau of Census,
"Monthly Report EM 545."
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Coal
Financial Reporting Regions
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A geographic
classification of areas with coal resources, which is used
for financial reporting of coal statistics.
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Coal
Gasification
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Any of a variety of processes by
which coal is converted to a gas.
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Coal
Imports
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Amount
of foreign coal shipped to the United States, as reported in
the U.S. Department of Commerce, Bureau of the Census,
"Monthly Report IM 145."
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Coal
Mining Productivity
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Coal
mining productivity is calculated by dividing total coal
production by the total direct labor hours worked by all
mine employees.
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Coal
Preparation/Washing
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The
treatment of coal to reject waste. In its broadest sense,
preparation is any processing of mined coal to prepare it
for market, including crushing and screening or sieving the
coal to reach a uniform size, which normally results in
removal of some non-coal material. The term coal preparation
most commonly refers to processing, including crushing and
screening, passing the material through one or more
processes to remove impurities, sizing the product, and
loading for shipment. Many of the processes separate rock,
clay, and other minerals from coal in a liquid medium; hence
the term washing is widely used. In some cases coal passes
through a drying step before loading.
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Coal-Producing
Regions
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A
geographic classification of areas where coal is produced. Some
States discontinue producing coal as reserves are depleted
or as production becomes uneconomic.
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Coal-Producing
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The States where
mined and/or purchased coal originates
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Coal
Rank
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The
classification of coals according to their degree of
progressive alteration from lignite to anthracite. In China,
the standard ranks of coal include brown coal, subbituminous
coal, soft coal, and anthracite and are based on fixed
carbon, volatile matter, heating value, and agglomerating
(or caking) properties.
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Coal
Stocks
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Coal
quantities that are held in storage for future use and
disposition. Note: When coal data are collected for a
particular reporting period (month, quarter, or year), coal
stocks are commonly measured as of the last day of this
period.
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Coal
Washery
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A Coal
Washery or Coal Preparation Plant is a plant that removes
ash from the coal to improve its quality as a commercial
product.
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Coal
Zone
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A
series of laterally extensive and (or) lenticular coal beds
and associated strata that arbitrarily can be viewed as a
unit. Generally, the coal beds in a coal zone are assigned
to the same geologic member or formation.
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Coalbed
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A
bed or stratum of coal. Also called a coal seam.
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Coal
generator
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A
generating facility that produces electricity and another
form of useful thermal energy (such as heat or steam) used
for industrial, commercial, heating, and cooling purposes.
To receive status as a qualifying facility (QF) under the
Public Utility Regulatory Policies Act (PURPA), the facility
must produce electric energy and "another form of
useful thermal energy through the sequential use of
energy," and meet certain ownership, operating, and
efficiency criteria established by the Federal Energy
Regulatory Commission (FERC). (See the Code of Federal
Regulation, Title 18, Part 292.)
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Coke
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A hard, dry carbon substance
produced by heating coal to a very high temperature in the
absence of air. Coke is used in the manufacture of iron and
steel.
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Coke
(coal)
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A
solid carbonaceous residue derived from low-ash, low-sulfur
bituminous coal from which the volatile constituents are
driven off by baking in an oven at temperatures as high as
2,000 degrees Fahrenheit so that the fixed carbon and
residual ash are fused together. Coke is used as a fuel and
as a reducing agent in smelting iron ore in a blast furnace.
Coke from coal is grey, hard, and porous and has a heating
value of 24.8 million Btu per short ton.
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Coke
(petroleum)
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A
residue high in carbon content and low in hydrogen that is
the final product of thermal decomposition in the
condensation process in cracking. This product is reported
as marketable coke or catalyst coke.
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Coke
Plants
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Plants
where coal is carbonized in slot or beehive ovens for the
manufacture of coke.
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Coking
Coal
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Bituminous
coal suitable for making coke. See Coke (coal).
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Combustion
Chamber
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The part of a boiler in which fuel
is burned.
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Compliance
Coal
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A
coal or a blend of coals that meets sulfur dioxide emission
standards for air quality without the need for flue gas
desulfurization.
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Consumer
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A
corporation, which uses coal as a fuel or raw material, eg.
A power utility, cement works, an industrial furnace
operator, a steel mill.
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Continuous
Mining
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A
form of room-and-pillar mining in which a continuous mining
machine extracts and removes coal from the working face in
one operation; no blasting is required.
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Conventional
Mining
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The
oldest form of room-and-pillar mining that consists of a
series of operations that involve cutting the coalbed so it
breaks easily when blasted with explosives or high-pressure
air, and then loading the broken coal.
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Cost,
Insurance, Freight (CIF)
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A
type of sale in which the buyer of the product agrees to pay
a unit price that includes the F.O.B. value of the product
at the point of origin plus all costs of insurance and
transportation. This type of transaction differs from a
"delivered" purchase in that the buyer accepts the
quantity as determined at the loading port (as certified by
the Bill of Loading and Quality Report) rather than pay on
the basis of the quantity and quality ascertained at the
unloading port. It is similar to the terms of an F.O.B.
sale, except that the seller, as a service for which he is
compensated, arranges for transportation and insurance.
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Culm
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Waste
from Pennsylvania anthracite preparation plants, consisting
of coarse rock fragments containing as much as 30 percent
small-sized coal; sometimes defined as including very fine
coal particles called silt. Its heat value ranges from 8 to
17 million Btu per short ton.
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Cumulative
Depletion
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The
sum in tons of coal extracted and lost in mining as of a
stated date for a specified area or a specified coal bed.
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CV
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Calorific
Value
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Demonstrated
Reserve Base
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A
collective term for the sum of coal in both measured and
indicated resource categories of reliability that represents
100 percent of the coal in these categories in place as of a
certain date. Includes beds of bituminous coal and
anthracite 28 inches or more thick and beds of subbituminous
coal 60 inches or more thick that occur at depths to 1
thousand feet. Includes beds of lignite 60 inches or more
thick that can be surface mined. Includes also thinner
and/or deeper beds that presently are being mined or for
which there is evidence that they could be mined
commercially at this time. Represents that portion of
identified coal resources from which reserves are
calculated.
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Demonstrated
Resources
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Same
qualifications as identified resources, but include measured
and indicated degrees of geologic assurance and excludes the
inferred.
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Demonstration
Phase
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A stage in the research and
development process during which a process or facility is
tested under anticipated operating conditions.
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Depleted
Resources
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Resources
that have been mined; include coal recovered, coal lost in
mining, and coal reclassified as sub economic because of
mining. See cumulative depletion.
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Depletion
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The
subtraction of both the tonnage produced and the tonnage
lost to mining from identified resources to determine the
remaining tonnage as of a certain time.
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Depletion
Factor
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The
multiplier applied to the tonnage produced to compute
depletion. This multiplier takes into account both the
tonnage recovered and the tonnage lost due to mining. The
depletion factor is the reciprocal of the recovery factor in
relation to a given quantity of production.
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Direct
Labor Hours
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Direct
labor hours worked by all mining employees at a mining
operation during the year. Includes hours worked by those
employees engaged in production, preparation, development,
maintenance, repair, shop or yard work, management,
technical or engineering work, and office workers. Excludes
vacation and leave hours.
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Dragline
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An excavating machine that uses a
bucket operated and suspended by lines or cables, one of
which lowers the bucket from the boom; the other, from which
the name of the machine is derived, allows the bucket to
swing out from the machine or to be dragged toward the
machine to remove overburden above a coal seam.
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Dredge
Mining
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A
method of recovering coal from rivers or streams.
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Drift
Mine
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An
underground mine that has a horizontal or nearly horizontal
entry driven along to a coalbed exposed in a hillside.
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Dry
(Coal) Basis
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Coal
quality data calculated to a theoretical basis in which no
moisture is associated with the sample. This basis is
determined by measuring the weight loss of a sample when its
inherent moisture is driven off under controlled conditions
of low temperature air-drying followed by heating to just
above the boiling point of water (104 to 110 degrees
centigrade).
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DWT
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Deadweight
tons. Deadweight cargo capacity is the weight in tons or
tonnes of the cargo required to sink the ship to her
loadline after allowing for bunkers, stores, etc.
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Electricity
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A
form of energy generated by friction, induction, or chemical
change that is caused by the presence and motion of
elementary charged particles of which matter consists.
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Electricity
Generation
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The
process of producing electric energy or transforming other
forms of energy into electric energy. Also the amount of
electric energy produced or expressed in watt-hours (Wh).
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Electricity
Generation, Gross
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The
total amount of electric energy produced by the generating
station or stations, measured at the generator terminals.
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Electricity
Generation, Net
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Gross
generation less electricity consumed at the generating plant
for station use. Electricity required for pumping at
pumped-storage plants is regarded as plant use and is
deducted from gross generation.
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Electric
Power Plant
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A
station containing prime movers, electric generators, and
auxiliary equipment for converting mechanical, chemical,
and/or fission energy into electric energy.
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Electric
Power Sector
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The
electric power sector (electric utilities and independent
power producers) comprises electricity-only and
combined-heat-and-power (CHP) plants whose primary business
is to sell electricity, or electricity and heat, to the
public.
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Electric
Utility
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A
corporation, person, agency, authority, or other legal
entity or instrumentality that owns and/or operates
facilities within the United States, its territories, or
Puerto Rico for the generation, transmission, distribution,
or sale of electric energy primarily for use by the public
and files forms listed in the Code of Federal Regulations,
Title 18, Part 141. Facilities that qualify as co generators
or small power producers under the Public Utility Regulatory
Policies Act (PURPA) and exempt wholesale generators under
Energy Policy Act of 1992 are not considered electric
utilities. See definition of nonutility power producer.
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Electric
Utility Sector
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The
electric utility sector consists of privately and publicly
owned establishments that generate, transmit, distribute, or
sell electricity primarily for use by the public and that
meet the definition of an electric utility. Nonutility power
producers are not included in the electric utility sector.
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Electrostatic
Precipitator
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An electrical device for removing
fine particles (fly ash) from combustion gases prior to
release from a power plant's stack.
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Energy
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The capacity to do work; more
commonly used as an all-encompassing generic term describing
fuel sources used to provide power.
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Energy Mix
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The combination of sources used to
provide energy at any given time and place. Energy sources
include coal, oil, gas, water (hydro), uranium (nuclear),
wind, sunlight, geothermal and others.
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Energy
Consumption
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The
use of energy as a source of heat or power or as an input in
the manufacturing process.
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Environmental
Restrictions
|
In
reference to coal accessibility, land-use restrictions that
constrain, postpone, or prohibit mining in order to protect
environmental resources of an area; for example, surface- or
groundwater quality, air quality affected by mining, or
plants or animals or their habitats.
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Estimated
Recoverable Reserves
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See
recoverable reserves.
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Fas
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Free
alongside. If a charter party provides for delivery of cargo
free alongside it is the responsibility of the shipper to
arrange for delivery of the cargo within reach of cargo
handling equipment at the port or on another vessel.
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F.A.S.
Value
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Free
alongside ship value. The value of a commodity at the port
of exportation, generally including the purchase price plus
all charges incurred in placing the commodity alongside the
carrier at the port of exportation in the country of
exportation.
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Federal
Coal Lease
|
A
lease granted to a mining company to produce coal from land
owned and administered by the Federal Government in exchange
for royalties and other revenues.
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Federal
Energy Regulatory Commission (FERC)
|
A
quasi-independent regulatory agency within the Department of
Energy having jurisdiction over inter-state electricity
sales, wholesale electric rates, hydro-electric licensing,
natural gas pricing, oil pipeline rates, and gas pipeline
certification.
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FIO
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Free in
and out. This expression means that it is the responsibility
of the charterer to load, or the consignee to discharge, the
cargo for their respective accounts, that is free of expense
to the owners of the vessel.
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Fixed
Carbon
|
The
nonvolatile matter in coal minus the ash. Fixed carbon is
the solid residue other than ash obtained by prescribed
methods of destructive distillation of a coal. Fixed carbon
is the part of the total carbon that remains when coal is
heated in a closed vessel until all volatile matter is
driven off.
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Floor
|
The
upper surface of the stratum underlying a coal seam. In
coals that were formed in persistent swamp environments, the
floor is typically a bed of clay, known as "under
clay," representing the soil in which the trees or
other coal-forming swamp vegetation was rooted.
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Fluidized
Bed
Combustion
|
A process that has a high capability of removing sulphur from coal
during combustion. Crushed coal and limestone are suspended
in the combustion chamber in the bottom of a boiler by an
upward stream of hot air. The coal is burned in this
fluid-like mixture. Instead of being released as emissions,
sulphur from combustion gases combines with the limestone to
form a solid compound recovered with the ash.
|
|
FOB
|
Free on
board. Stipulates that the seller is to deliver the goods on
board the vessel free of cost to the buyer at the port named
in the sales contract.
|
|
F.O.B.
Mine Price
|
The
free on board mine price. This is the price paid for coal at
the mining operation site. It excludes freight or shipping
and insurance costs.
|
|
FOBT
|
Free on
board and trimmed. The trimmed indicates that the cargo has
been trimmed within the hold for the sake of the ships
stability and to make room for additional cargo.
|
|
FOR
|
Free on
rail.
|
|
Foreign-Controlled
Firms
|
Foreign-controlled
firms are U.S. coal producers with more than 50 percent of
their stock or assets owned by a foreign firm.
|
|
Fossil-Fuel
Electric Generation
|
Electric
generation in which the prime mover is a turbine rotated by
high-pressure steam produced in a boiler by heat from
burning fossil fuels.
|
|
Gasification
|
(see coal gasification)
|
|
Geologic
Assurance
|
State
of sureness, confidence, or certainty of the existence of a
quantity of resources based on the distance from points
where coal is measured or sampled and on the abundance and
quality of geologic data as related to thickness of
overburden, rank, quality, thickness of coal, areal extent,
geologic history, structure, and correlations of coal beds
and enclosing rocks. The degree of assurance increases as
the nearness to points of control, abundance, and quality of
geologic data increases.
|
|
Geologic
Considerations
|
Conditions
in the coal deposit or in the rocks in which it occurs that
may complicate or preclude mining. Geologic considerations
are evaluated in the context of the current state of
technology and regulations, so the impact on mining may
change with time.
|
|
Geological
Classification
|
Rank is a
term that signifies the degree of coalification that the
sediments that constitute the coal have undergone. Rank
increases from lignite to semi-bituminous to bituminous to
semi-anthracite to anthracite. In the database coal reserves
have been classified by rank.
|
|
Geotechnical
Engineering
|
The branch of engineering that
specializes in assessing the stability and strength of soil
and rock materials, as well as groundwater conditions. In
mining, geotechnical engineering principles are used to
determine the appropriate design of mine features such as
pit walls, tunnels and earthen embankments.
|
|
Geothermal
Energy
|
Energy
from the internal heat of the earth, which may be residual
heat, friction heat, or a result of radioactive decay. The
heat is found in rocks and fluids at various depths and can
be extracted by drilling and/or pumping.
|
|
Greenhouse Effect
|
A misnomer for a natural
phenomenon that occurs when so-called 'greenhouse gases'
trap radiated heat in the atmosphere. The greenhouse effect
is actually a minor portion of a complex and dynamic process
of heating and cooling that occurs in the earth's
atmosphere. This natural process of heating and cooling also
includes the fluid dynamics associated with atmospheric
moisture (such as clouds), oceans and other surface water,
soot and other dust particles known as aerosols. The entire
heating and cooling cycle warms the atmosphere and makes
life on earth possible.
|
|
Greenhouse
Gases
|
Gases such as carbon dioxide (CO2),
water vapor, methane (CH4), nitrous oxide (NO2),
and other trace gases which restrict the re-radiation of
infrared heat back into the atmospheres thus .
|
|
Gross
Domestic Product (GDP)
|
The
total value of goods and services produced by labor and
property in the United States. As long as the labor and
property are located in the United States, the supplier
(that is, the workers and, for property, the owners) may be
either U.S. residents or residents of foreign countries.
|
|
Hand
Loading
|
An
underground loading method which removes coal from the
working face by manual labor through the use of a shovel for
conveyance to the surface.
|
|
High
wall
|
The
unexcavated face of exposed over-burden and coal in a
surface mine.
|
|
Hopper
|
A bin or funnel that is loaded
from the top and which discharges through a door or chute at
the bottom.
|
|
Hydroelectric
Power
|
The
harnessing of flowing water to produce mechanical or
electrical energy.
|
|
Hydroelectricity
|
Electricity generated using
falling water as an energy source.
|
|
Hypothetical
Resources
|
Undiscovered
coal resources in beds that may reasonably be expected to
exist in known mining districts under known geologic
conditions. In general, hypothetical resources are in broad
areas of coalfields where points of observation are absent
and evidence is from distant outcrops, drill holes, or
wells. Exploration that confirms their existence and better
defines their quantity and quality would permit their
reclassification as identified resources. Quantitative
estimates are based on a broad knowledge of the geologic
character of coalbed or region. Measurements of coal
thickness are more than 6 miles apart. The assumption of
continuity of coalbed is supported only by geologic
evidence.
|
|
Identified
Resources
|
Specific bodies of coal whose location, rank, quality, and
quantity are known from geologic evidence supported by
engineering measurements. Included are beds of bituminous
coal and anthracite 14 inches or more thick and beds of
subbituminous coal and lignite 30 inches or more thick that
occur at depths to 6,000 feet and whose existence and
quantity have been delineated within specified degrees of
geologic assurance as measured, indicated, or inferred.
|
|
Illinois
Basin
|
See
Coal-Producing Regions.
|
|
Implicit
Price Deflator
|
The
implicit price deflator, published by the U.S. Department of
Commerce, Bureau of Economic Analysis, is used to convert
nominal figures to real figures.
|
|
Indicated
Resources
|
Coal
for which estimates of the rank, quality, and quantity have
been computed partly from sample analyses and measurements
and partly from reasonable geologic projections. Indicated
resources are computed partly from specified measurements
and partly from projection of visible data for a reasonable
distance on the basis of geologic evidence. The points of
observation are 0.5 to 1.5 miles apart. Indicated coal is
projected to extend as a 0.5-mile-wide belt that lies more
than 0.25 miles from the outcrop or points of observation or
measurement.
|
|
Industrial
Restrictions
|
Land-use
restrictions that constrain, postpone, or prohibit mining in
order to meet other industrial needs or goals; for example,
resources not mined due to safety concerns or due to
industrial or societal priorities, such as to preserve oil
or gas wells that penetrate the coal reserves; to protect
surface features such as pipelines, power lines, or company
facilities; or to preserve public or private assets, such as
highways, railroads, parks, or buildings.
|
|
Industrial
Sector
|
The
industrial sector is comprised of manufacturing industries
that make up the largest part of the sector, along with
mining, construction, agriculture, fisheries, and forestry.
Establishments in the sector range from steel mills, to
small farms, to companies assembling electronic components.
|
|
Inferred
Reserve Base
|
the
resources in the inferred reliability category that meet the
same criteria of bed thickness and depth from surface as the
demonstrated reserve base.
|
|
Inferred
Resources
|
Coal
in unexplored extensions of demonstrated resources for which
estimates of the quality and size are based on geologic
evidence and projection. Quantitative estimates are based
largely on broad knowledge of the geologic character of the
bed or region and where few measurements of bed thickness
are available. The estimates are based primarily on an
assumed continuation from demonstrated coal for which there
is geologic evidence. The points of observation are 1.5 to 6
miles apart. Inferred coal is projected to extend as a
2.25-mile-wide belt that lies more than 0.75 miles from the
outcrop or points of observation or measurement.
|
|
Interior
Region
|
See
Coal-Producing Regions.
|
|
Jack
|
One
who works in a specified manual trade. Often used in
combination
|
|
Land-use
Restrictions
|
Constraints
placed upon mining by societal policies to protect surface
features or entities that could be affected by mining.
Because laws and regulations may be modified or repealed,
the restrictions, including industrial and environmental
restrictions, are subject to change.
|
|
Lignite
|
a low-rank coal with a relatively
high moisture and low heat/energy content. Ranging in color
from black to brown, lignite is used in power generation.
|
|
Liquefaction
|
The process of converting coal into a synthetic liquid fuel, similar in
nature to crude oil and other refined products.
|
|
Longwall
Mining
|
An
automated form of underground coal mining characterized by
high recovery and extraction rates, feasible only in
relatively flat-lying, thick, and uniform coalbeds. A
high-powered cutting machine is passed across the exposed
face of coal, shearing away broken coal, which is
continuously hauled away by a floor-level conveyor system.
Long wall mining extracts all machine-minable coal between
the floor and ceiling within a contiguous block of coal,
known as a panel, leaving no support pillars within the
panel area. Panel dimensions vary over time and with mining
conditions but currently average about 900 feet wide (coal
face width) and more than 8,000 feet long (the minable
extent of the panel, measured in direction of mining).
Longwall mining is done under movable roof supports that are
advanced as the bed is cut. The roof in the mined-out area
is allowed to fall as the mining advances.
|
|
Low Sulphur Coal
|
Coal that has a sulphur content
generally ranging from 0.1 per cent to 1.0 per cent. All
western Canadian coal is low in sulphur.
Metallurgical coal The type of coal which is converted to
coke for use in manufacturing steel; often referred to as
coking coal.
|
|
Low-Volatile
Bituminous Coal
|
See
Bituminous Coal.
|
|
Manufacturing
(except coke plants)
|
Those
industrial users/plants, not including coke plants, which
are engaged in the mechanical or chemical transformation of
materials or substances into new (i.e., finished or
semifinished) products. Includes coal used for
gasification/liquefaction.
|
|
Marginal
Reserves
|
Borders
on being economic. See economic.
|
|
Measured
Resources
|
Coal
for which estimates of the rank, quality, and quantity have
been computed, within a high degree of geologic assurance,
from sample analyses and measurements from closely spaced
and geologically well known sample sites. Measured resources
are computed from dimensions revealed in outcrops, trenches,
drill holes and mine workings,. The points of observation
and measurement are so closely spaced and the thickness and
extent of coals are so well defined that (for older
estimates) the tonnage was judged to be accurate within 20
percent of true tonnage (statistical measures of error are
no longer considered reliable for most measured resources).
Although the spacing of the points of observation necessary
to demonstrate continuity of the coal differs from region to
region according to the character of the coalbeds, the
points of observation are not greater than 0.5 mile apart.
Measured coal is projected to extend as a 0.25-mile-wide
belt from the outcrop or points of observation or
measurement.
|
|
Medium-Volatile
Bituminous Coal
|
See
Bituminous Coal.
|
|
Meta-Anthracite
|
See
Anthracite.
|
|
Metallurgical
Coal
|
a term used to describe varieties
of bituminous coal that are converted into coke for use in
the steel making process.
|
|
Methane
|
The most simple of the
hydrocarbons formed naturally from the decay of vegetative
matter, similar to that which formed coal. It is the
principal component of natural gas and is a radiative gas.
|
|
Metric
Ton
|
A
unit of weight equal to 2,204.6 pounds.
|
|
Minable
|
Capable
of being mined under current mining technology and
environmental and legal restrictions, rules, and
regulations.
|
|
Mining
Method
|
Coal
mining operations can be either open cut or underground.
There are then specific mining methods, which describe the
techniques used in more detail.
|
|
Moist
(Coal) Basis
|
"Moist"
coal contains its natural inherent or bed moisture, but does
not include water adhering to the surface. Coal analyses
expressed on a moist basis are performed or adjusted so as
to describe the data when the coal contains only that
moisture which exists in the bed in its natural state of
deposition, and when the coal has not lost any moisture due
to drying.
|
|
Mtce
|
Mega tonne of coal equivalent
|
|
Natural
Gas
|
A
mixture of hydrocarbons and small quantities of various
nonhydrocarbons existing in the gaseous phase or in solution
with crude oil in under-ground reservoirs.
|
|
Natural
Gas (Dry)
|
The
marketable portion of natural gas production, which is
obtained by subtracting extraction losses, including natural
gas liquids removed at natural gas processing plants, from
total production.
|
|
Nitrogen Oxides (NOx)
|
Formed when nitrogen (N2) combines
with oxygen (O2) in the burning of fossil fuels, from the
natural degradation of vegetation, and from the use of
chemical fertilizers. NOx gasses are a
significant component of acid deposition and a precursor of
photochemical smog. The primary source of nitrogen oxide
emissions is automobile exhaust.
|
|
Nominal
Price
|
The
price paid for a product or service at the time of the
transaction. The nominal price, which is expressed in
current dollars, is not adjusted to remove the effect of
changes in the purchasing power of the dollar.
|
|
Nonutility
Power Producers
|
A
corporation, person, agency, authority, or other legal
entity or instrumentality that owns electric generating
capacity and is not an electric utility. Nonutility power
producers include qualifying cogenerators, qualifying small-
power producers, and other nonutility generators (including
independent power producers) without a designated franchised
service area and which do not file forms listed in the Code
of Federal Regulations, Title 18, Part 141. (See Electric
Utility.)
|
|
North
American Industry Classification System (NAICS)
|
A
standardized set of codes that categorizes industries into
groups with similar economic activities, used by the U.S.,
Canada, and Mexico. The NAICS codes replace the SIC codes.
|
|
Northern
Appalachian Region
|
See
Coal-Producing Regions.
|
|
Nuclear
Electric Power
|
Electricity
generated by an electric power plant whose turbines are
driven by steam generated in a reactor by heat from the
fissioning of nuclear fuel.
|
|
Number
of Mines
|
The
number of mines, or mines collocated with preparation plants
or tipples, located in a particular geographic area (State
or region). If a mine is mining coal across two States, then
it is counted as two operations. This is done so that EIA
can separate production by State.
|
|
Number
of Mining Operations
|
The
number of mining operations includes preparation plants with
greater than 5,000 total direct labor hours. Mining
operations that consist of a mine and preparation plant, or
a preparation plant only, will be counted as two operations
if the preparation plant processes both underground and
surface coal. Excluded are silt, culm, refuse bank, slurry
dam, and dredge operations except for Pennsylvania
anthracite. Excludes mines producing less than 10,000 short
tons of coal during the year.
|
|
Open
Market Coal
|
Coal
sold in the open market, i.e., coal sold to companies other
than the reporting company's parent company or an operating
subsidiary of the parent company.
|
|
Operating
Subsidiary
|
A
company which is controlled through the ownership of voting
stock, or a corporate joint venture in which a corporation
is owned by a small group of businesses as a separate and
specific business or project for the mutual benefit of the
members of the group.
|
|
Other
Industrial Plant
|
Industrial
users, not including coke plants, engaged in the mechanical
or chemical transformation of materials or substances into
new products (manufacturing); and companies engaged in the
agriculture, mining, or construction industries.
|
|
Other
Power Producers
|
Independent
power producers that generate electricity and co-generation
plants that are not included in the other industrial, coke
and commercial sectors.
|
|
Overburden
|
Any
material, consolidated or unconsolidated, that overlies a
coal deposit.
|
|
Ozone (3)
|
A bluish toxic gas, with a pungent
odor, formed of three oxygen atoms rather than the usual
two. Occurs in the stratosphere and plays a role in
filtering out ultraviolet radiation from the sun's rays. At
ground level ozone is a precursor of photochemical smog.
|
|
Parent
Company
|
A
company, which solely or jointly owns the reporting, company
and which is not itself a subsidiary of, or owned by,
another company.
|
|
Peat
|
A dark brown or black deposit
resulting from the partial decomposition of vegetative
matter in marshes and swamps.
|
|
Percent
Utilization
|
The
ratio of total production to productive capacity, times 100.
|
|
Petroleum
Coke
|
See
Coke (petroleum).
|
|
Pit Ponies
|
Small horses, mules, or ponies that were used to pull coal shuttle cars
from underground mines during the 1800s.
|
|
Port
- Discharge
|
A port
where coal is unloaded from ships.
|
|
Port
Load
|
A port
where coal is loaded onto ships.
|
|
Port
Load & Discharge
|
A port
where coal can be either loaded or discharged.
|
|
Preparation
Plant
|
A
facility at which coal is crushed, screened, and
mechanically cleaned.
|
|
Producer
|
A company
that operates coal mines.
|
|
Producer
and Distributor Coal Stocks
|
Producer
and distributor coal stocks consist of coal held in stock by
producers/distributors at the end of a reporting period.
|
|
Productive
Capacity
|
The
maximum amount of coal that a mining operation can produce
or process during a period with the existing mining
equipment and/or preparation plant in place, assuming that
the labor and materials sufficient to utilize the plant and
equipment are available, and that the market exists for the
maximum production.
|
|
Proved Reserves
|
Those quantities which geological and engineering information indicate
with reasonable certainty can be recovered in the future
from known deposits under existing economic and operating
conditions.
|
|
Quadrillion
Btu
|
1015 Btu.
|
|
Quality
or Grade
|
An
informal classification of coal relating to its suitability
for use for a particular purpose. Refers to individual
measurements such as heat value, fixed carbon, moisture,
ash, sulfur, major, minor, and trace elements, coking
properties, petrologic properties, and particular organic
constituents. The individual quality elements may be
aggregated in various ways to classify coal for such special
purposes as metallurgical, gas, petrochemical, and blending
usages.
|
|
Radiative Gases
|
Any of the natural or man-made
gases which, when released, accumulate in the atmosphere. A
characteristic of these gases is that they tend to allow the
sun's heat to pass through to earth but do not allow the
heat radiated back from the earth to escape from the
atmosphere.
|
|
Real
Price
|
A price that has been adjusted to remove the effect of
changes in the purchasing power of the dollar. Real prices,
which are expressed in constant dollars, usually reflect
buying power relative to a base year.
|
|
Recoverability
|
In
reference to accessible coal resources, the condition of
being physically, technologically, and economically minable.
Recovery rates and recovery factors may be determined or
estimated for coal resources without certain knowledge of
their economic minability; therefore, the availability of
recovery rates or factors does not predict recoverability.
|
|
Recoverable
Coal
|
Coal
that is, or can be, extracted from a coal bed during mining.
|
|
Recoverable
Reserves at Producing Mines
|
The
amount of in situ coal that can be recovered by mining
existing reserves at mines reporting on Form EIA-7A.
|
|
Recoverable
Reserves, Estimated Recoverable Reserves
|
Reserve
estimates (broad meaning) based on a demonstrated reserve
base adjusted for assumed accessibility factors and recovery
factors. The term is used by EIA to distinguish estimated
recoverable reserves, which are derived without specific
economic feasibility criteria by factoring (downward) from a
demonstrated reserve base for one or more study areas or
regions, from recoverable reserves at active mines, which
are aggregated (upward) from reserve estimates reported by
currently active, economically viable mines on Form EIA-7A.
|
|
Recoverable
Reserves of Coal
|
An
estimate of the amount of coal that can be recovered (mined)
from the accessible reserves of the demonstrated reserve
base.
|
|
Recovery
Factor
|
The
percentage of total tons of coal estimated to be recoverable
from a given area in relation to the total tonnage estimated
to be in the demonstrated reserve base. For the purpose of
calculating depletion factors only, the estimated recovery
factors for the demonstrated reserve base generally are 50
percent for underground mining methods and 80 percent for
surface mining methods. More precise recovery factors can be
computed by determining the total coal in place and the
total coal recoverable in any specific locale.
|
|
Recovery
Percentage
|
The
percentage of coal that can be recovered from the coal
deposits at existing mines.
|
|
Refuse
Bank
|
A
repository for waste material generated by the coal cleaning
process.
|
|
Refuse
Mine
|
A
surface mine where coal is recovered from previously mined
coal. It may also be known as a silt bank, culm bank, refuse
bank, slurry dam, or dredge operation.
|
|
Regional
Reserves, Regional Reserve Estimates
|
Same
as reserves; alternative wording is used by EIA to
distinguish regional reserves, which are derived by
factoring (downward) from a demonstrated reserve base for
one or more study areas or regions, from reserves at active
mines, which are aggregated (upward) from reserve estimates
reported by individual mines on Form EIA-7A.
|
|
Remaining
(Resources/Reserves)
|
The
amount of coal in the ground after some mining, excluding
coal in the ground spoiled or left in place for which later
recovery is not feasible.
|
|
Report
Year
|
The
calendar year beginning at 12:00 a.m. January 1 and ending
at 11:59 p.m. December 31.
|
|
Reserve(s)
|
Root
meaning: The amount of in-situ coal in a defined area that
can be recovered by mining at a sustainable profit at the
time of determination. Broad meaning: That portion of the
demonstrated reserve base that is estimated to be
recoverable at the time of determination. The reserve is
derived by applying a recovery factor to that component of
the identified resources of coal designated as the
demonstrated reserve base.
|
|
Residential
and Commercial Sector
|
Housing
units; wholesale and retail businesses (except coal
wholesale dealers); health institutions (hospitals); social
and educational institutions (schools and universities); and
Federal, State, and local governments (military
installations, prisons, office buildings).
|
|
Resources
|
Naturally
occurring concentrations or deposits of coal in the Earth's
crust, in such forms and amounts that economic extraction is
currently or potentially feasible.
|
|
Roof
|
The
rock immediately above a coal seam. The roof is commonly
shale, often carbonaceous and softer than rocks higher up in
the roof strata.
|
|
Room-and-Pillar
Mining
|
The
traditional method of underground mining in which the mine
roof is supported mainly by coal pillars left at regular
intervals. Rooms are places where the coal is mined; pillars
are areas of coal left between the rooms. Room-and-pillar
mining is done either by conventional or continuous mining.
|
|
Royalties
|
Payments,
in money or kind, of a stated share of production from
mineral deposits, by the lessee to the lessor. Royalties may
be an established minimum, a sliding-scale, or a step-scale.
A step-scale royalty rate increases by steps as the average
production on the lease increases. A sliding-scale royalty
rate is based on average production and applies to all
production from the lease.
|
|
Run-of-mine
|
The
raw coal recovered from a mine, prior to any treatment.
|
|
Salable
Coal
|
The
shippable product of a coal preparation plant or mine.
Depending on customer specifications, salable coal may be
run-of-mine, crushed-and-screened (sized) coal, or the clean
coal yield from a preparation plant.
|
|
Sales
Volume
|
The
reported output from Federal and/or Indian lands, the basis
of royalties. It is approximately equivalent to production,
which includes coal sold, and coal added to stockpiles.
|
|
Sample
|
A
representative fraction of a coal bed collected by approved
methods, guarded against contamination or adulteration, and
analyzed to determine the nature; chemical, mineralogical,
and (or) petrography composition; percentage or
parts-per-million content of specified constituents; heat
value; and possibly the reactivity of the coal or its
constituents.
|
|
Scoop
Loading
|
An
underground loading method by which coal is removed from the
working face by a tractor unit equipped with a hydraulically
operated bucket attached to the front; also called a
front-end loader.
|
|
Scrubber
|
Any of several forms of
chemical/physical devices that operate to remove sulphur
compounds formed as a result of fossil-fuel combustion.
These devices normally combine the sulphur in gaseous
emissions with another chemical medium to form inert
compounds, which can then be removed for disposal.
|
|
Seam
|
A
bed of coal lying between a roof and floor. Equivalent term
to bed, commonly used by industry.
|
|
Shaft
Mine
|
An
underground mine that reaches the coalbed by means of a
vertical shaft. In addition to the passages providing entry
to the coalbed, a network of other passages are also dug,
some to provide access to various parts of the mine and some
for ventilation.
|
|
Shearer
|
A rotating cutting device used in
underground mining to remove coal from the coal seam.
|
|
Shipper
|
A company,
or individual, which sells coal. It is usually a producer or
a trader.
|
|
Short
Ton
|
A
unit of weight equal to 2,000 pounds.
|
|
Shortwall
Mining
|
A
form of underground mining that involves the use of a
continuous mining machine and movable roof supports to shear
coal panels 150 to 200 feet wide and more than half a mile
long. Although similar to longwall mining, shortwall mining
is generally more flexible because of the smaller working
area. Productivity is lower than with longwall mining
because the coal is hauled to the mine face by shuttle cars
as opposed to conveyors.
|
|
SIC
|
See
Standard Industrial Classification.
|
|
Silt
|
Waste
from Pennsylvania anthracite preparation plants, consisting
of coarse rock fragments containing as much as 30 percent
small-sized coal; sometimes defined as including very fine
coal particles called silt. Its heat value ranges from 8 to
17 million Btu per short ton. Synonymous with culm.
|
|
Silt,
Culm Refuse Bank, or Slurry Dam Mining
|
A
mining operation producing coal from these sources of coal.
(See refuse mine.)
|
|
Slope
Mine
|
An
underground mine in which the entry is driven at an angle to
reach the coal deposit.
|
|
Slurry
Dam
|
A
repository for the silt or culm from a preparation plant.
|
|
Solar
Energy
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The
radiant energy of the sun, which can be converted into other
forms of energy, such as heat or electricity.
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Southern
Appalachian Region
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See
Coal-Producing Regions.
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Standard
Industrial Classification (SIC)
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A
set of codes developed by the Office of Management and
Budget which categorizes industries to groups with similar
economic activities. SIC was superceded by the North
American Industry Classification System (NAICS) in 1997.
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Steam
Coal
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All
non-metallurgical coal.
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Stocks
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The
supply of coal or coke at a mine, plant, or utility at the
end of the reporting period.
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Strip
or Stripping Ratio
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The
amount of overburden that must be removed to gain access to
a unit amount of coal. A stripping ratio may be expressed as
(1) thickness of overburden to thickness of coal, (2) volume
of overburden to volume coal, (3) weight of overburden to
weight of coal, or (4) cubic yards of overburden to tons of
coal. A stripping ratio commonly is used to express the
maximum thickness, volume, or weight of overburden that can
be profitably removed to obtain a unit amount of coal.
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Sub-bituminous
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a generally soft coal with a
heating value between bituminous and lignite. It has low
fixed carbon and high percentages of moisture and volatile
material. Sub-bituminous coal is mainly used for generating
electricity.
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Subbituminous
Coal
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A
coal whose properties range from those of lignite to those
of bituminous coal and used primarily as fuel for
steam-electric power generation. It may be dull, dark brown
to black, soft and crumbly, at the lower end of the range,
to bright, jet black, hard, and relatively strong, at the
upper end. Subbituminous coal contains 20 to 30 percent
inherent moisture by weight. The heat content of
subbituminous coal ranges from 17 to 24 million Btu per ton
on a moist, mineral-matter-free basis. The heat content of
subbituminous coal consumed in the United States averages 17
to 18 million Btu per ton, on the as-received basis (i.e.,
containing both inherent moisture and mineral matter).
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Sulfur
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One
of the elements present in varying quantities in coal that
contributes to environmental degradation when coal is
burned. EIA classifies coal, in terms of pounds of sulfur
per million Btu as low (less than or equal to 0.60 pounds of
sulfur), medium (between 0.61 and 1.67 pounds of sulfur),
and high (greater than or equal to 1.68 pounds of sulfur).
When coal is sampled, sulfur content is measured as a
percent by weight of coal on an “as received” or
“dry” (moisture-free) basis.
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Sulphur Oxides(SOx)
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A family of gases, including
sulphur dioxide (SO2) formed when sulphur, or fossil fuels
containing sulphur, burn in air. Airborne sulphur compounds
may be converted to other substances that contribute to acid
deposition.
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Surface
Mine
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A
coalmine that is usually within a few hundred feet of the
surface. Earth and rock above or around the coal
(overburden) is removed to expose the coalbed, which is then
mined with surface excavation equipment such as draglines,
power shovels, bulldozers, loaders, and augers. Surface
mines include: area, contour, open-pit, strip, or auger
mine.
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Tectonic Forces
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Forces pertaining to, causing or
resulting from structural deformation of the earth's crust.
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Thermal
coal
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Coal that
is used as a fuel in applications other than metallurgical
ones. Typical uses are in steam raising for power generation
or other industrial applications and as a fuel in cement
kilns.
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Tipple
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A
central facility used in loading coal for transportation by
rail or truck.
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Ton
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An Imperial unit of weight
equivalent to 2,000 pounds or 907.2 kg. This is also known
as a "short ton".
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Tonne
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A metric unit of weight equivalent
to 1000 kg or 2,240 pounds. This is also known as a
"metric ton" or "long ton".
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Trader
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A company
or individual that trades in coal, usually taking positions
as a principal.
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Transportation
Leg
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The
Transportation Leg defines the journey of coal from the mine
by various means to a plant, which could be a barge loader,
a port, a rail loader or local power station, or other plant
as defined in the database.
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Transportation
Sector
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The
transportation sector consists of private and public
vehicles that move people and commodities. Included are
automobiles, trucks, buses, motorcycles, railroads and
railways (including streetcars), aircraft, ships, barges,
and natural gas pipelines.
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Turbine
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A machine that has propeller-like
blades which can be moved by flowing water or gas (including
steam) thereby rotating a component in a generator to
produce electricity.
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Underground
Mine
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A
mine where coal is produced by tunneling into the earth to
the coalbed, which is then mined with underground mining
equipment such as cutting machines and continuous, longwall,
and shortwall mining machines. Underground mines are
classified according to the type of opening used to reach
the coal, i.e., drift (level tunnel), slope (inclined
tunnel), or shaft (vertical tunnel).
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Underground
Mining
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The
extraction of coal or its products from between enclosing
rock strata by underground mining methods, such as room and
pillar, longwall, and shortwall, or through in-situ
gasification.
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Undiscovered
Resources
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Unspecified
bodies of coal surmised to exist on the basis of broad
geologic knowledge and theory. Undiscovered resources
include beds of bituminous coal and anthracite 14 inches or
more thick and beds of subbituminous coal and lignite 30
inches or more thick that are presumed to occur in unmapped
and unexplored areas to depths of 6,000 feet. The
speculative and hypothetical resource categories comprise
undiscovered resources.
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Volatile
Matter
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Matter that is driven off as gas
or vapor when coal is heated to about 9500° C.
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Weather
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Weather is the state of the
atmosphere at a given time that includes temperature,
precipitation, humidity, pressure, winds
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Western
Region
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See
Coal-Producing Regions.
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Xylovitrite
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To
print from a wood engraving.
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Yield
of coal
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An
amount yielded or produced; a product.
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