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the creek during the past few years has been carried on by Julius Powell
(Coulter Creek Mining Company) who has installed a complete, small
hydraulic plant, including a dam and ditch, a small sawmill, operated by
a Pelton wheel, and an electric lighting plant. The plant is located about
700 feet above the mouth of the first tributary creek. A No. 2 monitor
with 4-inch nozzle is used, the head of water being about 100 feet. About
80 miner’s inches would be available on the average throughout the hydrau-
lic season if the flood water could be stored. The present dam permits
of storage of water for work at intervals during the dry season, but the
flood water can not be conserved to any great extent. The sluice boxes
have an 8-inch grade and twenty-six to thirty 12-foot lengths are used.
As the creek has a fairly high gradient there is little difficulty in disposing
of the tailings. The bedrock was reached in the hydraulic pit in 1923
and is apparently in the deepest part of the channel. Some gold values
were found in a small thickness of gravels resting on the bedrock. At the
head of the pit in the valley bottom the bank is about 40 feet high and
consists mostly of glacial gravels with some silt and clay. As the sawmill
is located only about 100 feet above the head of the pit and the dam a short
distance farther up, they will have to be removed if operations are con-
tinued. ‘There is a considerable stretch of the creek above the plant which
has not been mined, but whether it will pay for hydraulicking is speculative,
as no adequate testing of the ground has been done. The hydraulic
operations during the past few years are said to have about paid expenses.

Slough Creek Mine

Slough Creek mine (Figure 23) is situated in the broad valley of
Slough creek opposite the mouth of Nelson creek and is reached by a road
turning off from the main highway at the mouth of Devils Lake creek.
Although no mining has been attempted since 1907, the mining operations
and development work are here somewhat fully described because of the
interesting problems involved, and because it has recently been proposed
to re-drill the ground to determine the depths and values. The ground
is known to have a maximum depth of about 287 feet and mining of the
bedrock gravels was attempted by sinking a shaft in bedrock at the north
side of the valley and driving a tunnel beneath the deepest part of the
channel, into which openings were made by upraises from the tunnel.
But, although pumping, to drain the ground and thus permit of mining of
the bedrock gravels, was carried on almost continuously for over five years
it was not found possible to reduce the water pressure except slightly.
Why this was the case forms one of the most interesting problems in
connexion with the mining operations. Some testing of the ground for
gold values was done by drilling and by determining the amounts of gold
in the small quantities of bedrock gravels obtained by breaking into the
channel at a few places, but whether the gravels will pay for mining if the
ground be drained was not definitely settled. The drilling was done with
an hydraulic jetting machine which proved fairly efficient in testing the
depth of the ground and the character of the strata passed through, but
was not considered efficient in determining the gold values in the gravels,

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