Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1940-01-13

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The site chosen for the quarry
was at Snake Butte, 151 miles
from Fort Peck. At the time OF
maximum production this was the
largest quarry of its type in the
United States. over six hundred
men were employed. working three
eight-hour shifts per day, seven
DAYS a week The quarry began
operations in the summer of 1897
and in three summers 4S5,O38
solid cubic yards of stone weighing
about 1871 600 tons were quar-
ried.
Snake Butte is located thirteen
miles south of Harlem, Mont,
which is some 140 miles west OF
Fort Peck. About ten square
miles in area, the butte rises few
hundred feet from the surrounding
plains. Varying from few feet to
a little over one hundred feet in
thickness, the butte represents an
erosional remnant of a basic an
desite or basalt sill The sill was
intruded into cretaceous sediments.
resting on a bed OF shale. In places
there is good columnar jointing.
The hundred-foot thickness faces
north, forming a cliff about a mile
and a half long; then slopes south
ward to the level of the surround
ing country. This butte was chosen
because of the comparatively proxi-
nifty of the suitable rock to the
dam.
To begin operations, a railroad
had to be built from Harlem to
the butte, Harlem already being
connected to Fort Peck by the
Great Northern railroad. Then a
railroad yard had to be cut and fill
ed about fifty feet below the base
of the igneous rock and directly
north of the cliff. These yards on
completion were about mile and
a half in length. and wide enough
for five sets of tracks. A little diff
ficulty was experienced in start
ing quarrying as the cliff was di-
rectly on the side of the tracks and
extensive blasting could not be
done. To get around this, a stiff
leg" was set up on the side of the
tracks and blasting was done by
snake-hole methods. AS the stone
was blasted the specification stone
was lifted by the stiff leg" and
placed on waiting flat cars AL
though very good rock was secur-
ed by this method it was soon seen
that this method of quarrying was
much too slow for the amount of
stone required
As soon as enough rock had been
removed to allow a track to be
built on the quarry floor, q four
main yards. Cars were taken up
this grade and loaded on the floor.
With this, coyote-hole blasting was
begun, which made much more
acceptable rock but also greater
proportion of waste.
When this method was started,
an adit on the level of the floor
was driven to the east of the main
working face and perpendicular to
the face, From this adit crosscuts
were driven parallel to the face
and fifty feet from the toe of the
face. These crosscuts were driven
between $50 and $50 feet long
When the crosscut was completed
it was loaded with black powder
and forty per cent dynamite and
then blasted. The broken rock was
then loaded onto railroad cars by
electric and gasoline shovels. AS
operations grew the face was en-
larged SO that finally a face of
about 1000 feet long was being
worked. To work this face two ad-
ditional adits were driven, one in
the center of the face and one on
the west end However, the time
came when the adits became so
long that the cost of driving them |
became too great. Another method |
was then used. This consisted prin-
eipaIly in driving a tunnel perpen-
dicular to and in the center of a
working face for a distance of fiji |
ty feet. This tunnel was called a |
stem and was driven on the level |
of the quarry floor From the end |
of the stem crosscuts were then
driven on either side parallel to
the face. This method was then |
used until operations ceased
The three main adits were tim
bered and tracks laid in them, and |
Butte mine care were used in the |
haulage of the muck. The cars were
trammed by hand and the muck |
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