PERMFILE103222

• Permit No: M1977559
• IBM Index Class Name: Permit File
• Doc Date: 12/13/1977
• Doc Name: APPLICATION FOR MLR PERMIT VALCO INC CANON CITY EAST PIT
• From: ENVIRONMENT INC
• To: DMLR
• Media Type: D
• Archive: No

~ • •
' EXH IBIT D (Cont'd)
The sand and gravel below the overburden on the affected
' land varies in thickness between twenty and twenty-five and
one half feet, as found in exploratory holes drilled in 1968.
'
Material extracted has r emained within this thickness range,
the average thickness being twenty-two to twenty-three feet.
The sand and gravel deposit is underlain by a relatively
impermeable grey shale. The shale acts as a bottom for the
pit throughout the operation except in a few rare cases
h
di
d
h
h
l
w
ere
rty san
s are encountered short of t
e s
a
e.
' During the test hole drilling water was encountered in
the first sands immediately beneath the overburden. The
' cvorking pits must be dewatered during excavation in order
to mine under primarily dry conditions. Because of dewatering,

only minimal amounts of water are present and subject to
' evaporation. Therefore, during the mining stages evaporation
is not a significant factor. Dewatering is conducted under
' Colorado Department of Health NPDES Permit No. CO-0024031
which expires on March 31, 1982. The waters are discharged
' i
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ifi
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ansas
o s
gn
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er are
ver.
' being used or will be used in the open pit mining operation.
Much of the area remains damp after dewatering. Thus, the
' application of water to control dust is not necessary.
Processing equipment is operated under Colorado Depart-
' ment of Health
Air Pollution Di
trol Per-
i
Co
i
E
i
i
,
v
s
m
ss
on
n
on,
' mit No. P-10,220 issued on October 17, 1977, with no expiration
date stipulated. {Pater from well number 016465-F located at
' the plant site is for industrial use, i.e. washing of sand
and gravel.
7