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THE COAL TRADE BULLETIN. 43
PROBLEMS IN MINING WEST KENTUCKY COAL*
By Newell G. Allord. Assistant Engineer St. Bernard Mining Company. Earlington. Ky.
The average man of practice will admit that,
even at its best, mining coal demands a high
grade of ingenuity on the part of managers and
engineers. Managers and engineers can readily
recall the instances when they thought they saw
their string's end as to the solution of a certain
coal mining problem. But just as the darkest
hour of night precedes the dawn of day, so are
these moments of unexpressed anxiety transformed
into those of relief. It only requires a
given length of time including a given number
of "problems" until the manager or engineer becomes
imbued with a profound faith in the old
belief that "everything comes out all right."
Even at the muleless, trackless, motorless mines
of Kansas, where the coal is stripped with a
dinky engine and a derrick, problems exist. So
taking all in all, the western coalfield of Kentucky
loses nothing through its need for solutions
to the problems of moment which surround
it.
Before entering a discussion of the problems,
it is best to scan the latest available report of
the Kentucky mine inspector and the government
Geological Survey's "Production of Coal in 1912."
In these reports it is estimated that the total
acreage of the state underlaid by available coal
measures, is approximately 16,670 square miles,
of which the western Kentucky coalfield embraces
38.3 per cent. We also find that Kentucky's coal
production is 1912 was, in round numbers, 16,491,-
000 tons—47.7 per cent, of which was produced
in the western field.
In connection with this 47.7 per cent., which
amounts to slightly less than 8,000,000 tons, it is
INTERESTING TO NOTE
that this tonnage was produced by 120 mines,
operated by 98 companies. A detailed classification
of the just mentioned mines and their outputs
has been arranged by the writer.
Of the 120 mines:
21 per cent, produced less than 10,000 tons.
51 per cent, produced less than 60,000 tons.
23 per cent, produced more than 100,000 tons.
2 companies operating IS mines produced
2,750,000 tons.
The most important problems in the western
Kentucky field, discussed in this paper, are dealt
with in the following order:
1. Robbing pillars.
2. Air passing through old works.
3. Ignition of No. 11 coal in old workings.
4. Prevention of oxidation.
•Presented by the Kentucky Mining Institute. Lexington,
Kentucky, Dec. 8. 1913.
5. Coal dust.
0. Shooting off the solid.
7. Fatalities.
S. Roof.
9. Wastes.
10. Pond sites.
11. Competition.
The workable measures in the western Kentucky
field, under the present development, are
with but few exceptions No. 9 and No. 11 as
identified by the Kentucky State Geological survey.
Being more consistent in occurrence, No. 9
supplies about three-fourths of the total output
of the field. This seam which is present in eight
counties, according to investigations to date, averages
5 feet in thickness. While this bed is most
generally
APPIiOACHED ISY SHAFTS
300 feet or less in depth, there are depressions
in some vicinities which make entrance possible
by slope or drift.
Seam No. 11, which lies from 40 to 100 feet
above No. 9, is the bed next in importance in
this field. It averages 6 feet in thickness.
Without a single exception the mines of western
Kentucky are developed by the room and
pillar method, with double or triple entries. The
triple entry system is used only in the larger
mines where the motor partings are projected
in the central entry; the side entries are used
for mule haulage and ventilation respectively.
This not only facilitates ventilation, but permits
of the motor parting being located nearer the
working rooms, thus reducing the mule haulage.
On the other hand, this efficiency is accompanied
by the additional cost of driving an extra entry.
Robbing pillars in working No. 11 coal is particularly
hazardous and impractical because of
the heavy, solid character of the limestone overlaying
it. In the first place, No. 11 coal is the
most friable of the western Kentucky coals and
crushing results where insufficient pillars have
been left. Another result obtaining from insufficient
pillars is the settling of the pillars under
pressure with the consequent heaving of the soft
fire clay bottom.
In some of the mines in this field, old works
are used as air courses. Gases generated by gob
and shale piles, are absorbed and carried along
by the air current.
The difficulties arising from this practice indicate
that it should be avoided in all cases. The
numerous
WOOOEN BItATTICES
to be maintained make it impossible to prevent