Gilpin observer., 1906-09-20

solution for the water problem, as 1t
presents it-clf in Cripple Creek and
vicinity, the cost Of pumping plant
that would drain the entire district be-
ing so enormous as to be prohibitive.
In his opinion the fact that the
group Of mines on the eastern and
southern side of the district, including
the indicator, Golden Circle, Gold
Coin and others, do not connect with
the drainage system at the present wa
ter level, as the plug of eruptive rocks
In the old volcano crater, which forms
the productive area, probably narrows
as 1t goes deeper. 1t is generally con-
ceded that the granite rim which sur
rounds the core of eruptive rock rest
ing in the crater, carries but little wa
ter and that all the water pumped out
of the mines comes from the porus
eruptive rock and from the fissures
which branch from the crater into the
surrounding granite. These fissures
have generally north and south d.
rection, and consequently the new tun-
mel will be driven east and west in Or
der to cut the greatest number of As
sures in the shortest distance. In Mr..
Brunton's opinion it will not be neces.
sary to crosscut the entire district in
order to drain it, although the COM
bined advantages of ventilation, pros
pecting and drainage might justify
such an expenditure.
The cost of pumping Is but one
item in the expense of working in wet
ground, experience having shown that
a man who is working in comfort ir
ordinary clothes is capable of one
third more work than man weighted
down with rubber clothes and boots.
In addition to this the loss in fines"
where the work is done in wet ground
is found to be very heavy. Taken al
together. according to Mr.. Brunton,
deep level draining would find differ
ence of at least twenty per cent in
favor of dry as against wet mining
The tunnel shaft from which heal
ing in both directions will be driven
will be $50 feet deep and will be pro-
vided with pumping apparatus, though
it is not anticipated that much water
will be encountered. The tunnel itself
will be seven feet wide by ten feet
high, probably double-tracked through
out, with drainage below the tracks
and room for ventilating pipe work.
men and cars above.
The following detailed figures on the
new tunnel are taken from the report
prepared by ID. w. Brunton for a COM
mittee appointed by the Cripple Creek
mine owners when the proposition of a
new drainage tunnel first presented It.
self:
Elevation of portal. 5000 feet;
depth below Cripple Creek drainage
tunnel, 40 feet; distance to FL Paso
shaft. 1850 feet; distance to main wa
ter channel, 1850 feet; distance from
portal to tunnel shaft, 1850 feet;
nf
quired two and one-tenth years; cost,
$430,O00; depth gained, 74O feet; cost
per vertical foot of depth gained,
$5S1.
William cambridge. superintendent
of the El Paso mine on Beacon hill, re-
Gently predicted that If the drainage
tunnel is not driven the time will come
when the ore hoisted will not be sufi-
cient to pay costs of pumping opera
tion; that without 1t mines must close,
and that far-sighted capitalists. know
ing the value of the mines, will pur-
chase the properties. drive the tunnel
and derive enormous benefits.
With this great enterprise unde-
way, mining men interested in the de-
velopment of Cripple Creek and the
upbuilding of Colorado generally are
jubilant. They say that the mining of
ore bodies at great depths now indi-
Gates that the values will extend to
unknown depths, and the problem OF
the future will not be SO much the wa
ter problem as it will be machinery
powerful enough to handle the rich ore
from the great depths where 1t will he
found.
Cripple Creek has an area of only six
square miles within the so-called pro-
ducing area. OF that area not one
tenth has been developed. OF the de-
veloped portion not fifty per cent. OF
the ground has been prospected to a
depth of 500 feet, and very small per
cent. has been developed to a depth OF
more than 900 feet.
Let from within that limited area
there are more than 200 openings
through which one or more operators
are taking out ore, the aggregate out.
put annually exceeding the total out
put of the state of California.