_GENERAL DOCUMENTS - C1981017 ‎(279)‎

• Permit No: C1981017
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Name: Bid Documents ‎(IMP)‎
• Media Type: D
• Archive: No

Jim Herron -2- March 17, 1982
The most prominent aquifer in the vicinity of the Mid-Continent operations is the
alluvial aquifer of Coal Creek. Yields in this aquifer are reported to average
20 gpm. Mid-Continent has completed 9 observation and production wells into
this alluvial aquifer, and the alluvium of several of the smaller drainages (see
Map IV-C-1 and Map III-E-1 of the permit application) . Depths of these wells
range from 10-75 feet. The water quality of the aquifer is _generally a Ca,Na,
Mg-HCO3 type with an average total dissolved solids concentration of 347 mg/1.
Iron and magnesium concentrations are high, but the water is still suitable for
domestic uses (see Section III-E-2 of the permit application) . The alluvial aquifer
is probably recharged by 3 mechanisms:
I) from the surface water during periods of high flow,
2) from the adjacent bedrock strata, and
3) from direct infiltration of precipitation and snowmelt.
The alluvial aquifer probably discharges to the following locations:
1) to the surface water during periods of low flow,
2) to the adjacent bedrock strata, and
3) to the alluvial aquifer of the Crystal River, farther downstream.
The only use of ground water from aquifers that have the potential to be impacted
by mining (the aquifers discussed above) is by the applicant. Several mine
production wells are completed into the alluvial aquifer of Coal Creek. See
Table III-C-3 of the permit application for a description of all private water
wells in the area. No wells are known to be completed into the coal-bearing
strata of the Mesa Verde Group in the vicinity of the mine.
Description of Applicant's Proposal
The applicant proposes to mine both the Coal Basin coal seam ("B" seam) and the
Dutch Creek coal seam ("V" seam) by underground mining methods (see Figure III-D-1
of the permit application for stratigraphic relationships) . The mine entries will
be located near the outcrop of the seams. No significant physical disturbance
of adjacent strata will occur as a result of the mine entries.
In addition, the applicant proposes to construct a tunnel which will connect the
2 seams currently being mined. This tunnel will be used to more efficiently
transport coal out of the mines. The tunnel entry will be located in the under-
lying Mancos Shale formation and will continue up the strati graphic section until
it intersects the Dutch Creek coal seam. It will cut through 3 sandstone units that
are considered potential aquifers. They are, in strati graphically ascending order,
the Cozzette, Rollins, and Middle Sandstones (see Figure III-D-1 of the permit
application) . The waste rock generated during the construction of this tunnel
will be disposed of on the banks of Dutch Creek.
A small amount of mine refuse and coal processing wastes will be generated by the
applicant during normal operations. The refuse will be disposed of in a small
tributary drainage of Dutch Creek. The coal processing wastes will be disposed of
in the Dutch Creek and Coal Creek drainages. See Map II-B-7 of the permit appli-
cation for the locations of these waste disposal areas.