2020-10-22_PERMIT FILE - C1981012A ‎(4)‎

• Permit No: C1981012A
• IBM Index Class Name: Permit File
• Doc Date: 10/22/2020
• Section_Exhibit Name: Section 2.05 Operation and Reclamation Plan
• Media Type: D
• Archive: Yes

An additional discussion of hydrologic impacts associated with the
Golden Eagle and New Elk Mines may be found in Exhibit 8, in the Water,
Waste and Land analysis entitled "Hydrology, Geology and Water Quality
in the vicinity of the Maxwell and Allen Mines."
Processing Plant Recycling within the Flooded Workings
In 1995, Basin proposed to pump a 40 percent by weight slurry from
the thickener of the coal processing plant down the rock slopes into the
mine and extract an equivalent volume of water for use in the processing
plant. This process will result in a slight increase in the elevation
of the water level in the mine, through the deposit of the fines, and a
deterioration in the quality of the water over time.
Data on flooding of the New Elk workings has been limited to
several probes of the workings through the East Portal air shaft since
December, 1993, and single probes of the Apache Canyon fan shaft and the
West Portal fan shaft. on 12/28/94, the water level was observed at
7065.2' in a hole drilled north of the Prep Plant and the Middle Fork of
the Purgatoire River, from which water will be recycled from the mine
(NEW -4). This elevation corresponds with flooding of the 286 acres of
mains with 5.7 x 108 gallons of water.
The slurry recycling project will maintain water quality of the
workings at concentrations which meet Colorado Ground Water Quality
Standards, assuming ideal mixing conditions within the mine. Basin will
pump as much as 700 gpm of slurry into the mine each year and 1.84 x 109
gallons over the five-year life of the project. This is equivalent to
pumping in 2.43 x 108 gallons of water in the first year and 1.22 x 109
gallons of water over the life of the project assuming that the slurry
is 34o solids by volume.
The middle member of the Raton formation, in which the coals are
found, consists of fine to medium grained sandstones interbedded with
siltstones and shales. A small number of water bearing zones within the
Raton are typically found in channel sandstone deposits of limited
horizontal extent. The Raton has not been developed for beneficial uses
extensively in the Stonewall/Weston area, due to the proximity of
shallow, alluvial waters along the Purgatoire River.
The Trinidad Sandstone has been identified as a regional aquifer.
It is located below the Lower Raton member and the Vermejo Formation at
a depth of 500'-900, below the Allen seam.
Vertical communication between the overburden and the underburden
appears to exist, but to be limited. The observed mine inflows can be
attributed to the coal seam (Exhibit 8), and to faults intersected by the
mine. The Raton and Vermejo are fine grained sedimentary deposits which
RN -6 2.05-96 (Repaginated 10/21/16)