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John Hopp, local manager. Additional boring was done, and the maximum
depth of the ground verified. It was then decided to sink a bedrock shaft
on the north side of the valley, and drive a long bedrock tunnel from the
bottom of the shaft to intercept the channel. A small shaft was sunk to
water-level and a tunnel driven 104 feet into the hill to bedrock, which
proved to be 50 feet from the surface. The main shaft, which has two
hoisting compartments and one pumping compartment, was then sunk,
the depth from the collar of the shaft to the floor of the main tunnel being
362 feet 4 inches. The elevation of the collar of the shaft is 50 feet above
the level of the surface of the ground at the deepest bore-hole. The main
tunnel is 8 feet wide and 7 feet high and was finally extended 1,230 feet
from the bottom of the shaft. The grade of the tunnel is 0-2 per cent. An
air lock was placed in the tunnel at a distance of 889 feet from the shaft.
It consisted of two air and water-proof steel doors 15 feet apart set in
steel and concrete bulkheads, openings being provided by means of pipes
for compressed air, ventilation, and drainage. It was designed to with-
stand a maximum pressure of 100 pounds to the square inch. It proved
efficient for pressures of 45 to 50 pounds which were frequently used, but
the doors bulged when a maximum pressure of 75 pounds was applied.
Its purposes were to prevent a heavy flow of water and mud into the
tunnel when openings were made into the channel, to prevent influx of
water when gravel was being removed, and in case of accident to the pumps
to prevent flooding of the mine. The pumping plant consisted of two
Worthington pumps of an estimated capacity of 500 gallons each per minute.
The pumps were placed in a pump chamber 28 feet by 234 feet by 8 feet
high, cut in the bedrock at the bottom of the shaft, the floor of the chamber
being 4 feet 6 inches above the level of the floor of the tunnel. The power
plant consisted of four 40-horsepower return tubular boilers using wood as
fuel. The complete plant was installed in November, 1901, and attempts
at draining the ground and mining the gravels began shortly afterwards
and continued with few interruptions until September, 1907. In 1905 a
new company, known as The Slough Creek Gravel Gold, British Columbia,
was formed to operate the mine. Sir James Bevan-Edwards was president
and J. D. Kendall of London, England, consulting engineer. Archibald
Russell and Archibald Stark were local managers during parts of 1905,
Bertram Mellon was manager in 1906, and H. Waters in 1907. In May,
1906, the company went into liquidation and a new company was formed
under the name “Slough Creek, Limited.’ The reconstruction of the
company furnished a working capital of £40,000.

The mining operations during the period from December, 1901, to
September, 1907, consisted very largely of driving crosscut tunnels and
inclined upraises to the old channel from near the end of the main tunnel.
These were intended to drain the gravels and relieve the pressure sufficiently
to permit of mining them. Several hundred feet of drifts were run both
upstream and downstream from the main tunnel, many bore-holes were
put up through the bedrock to the gravels, and many small drives extended
to the channel. It was found, however, even in the case of 2-foot drives,
that on breaking into the channel, so great a pressure developed, either
suddenly or gradually, that the timber would be crushed and the drive
would have to be closed with a bulkhead and abandoned. During the

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