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An additional discussion of hydrologic impacts associated with the <br />Golden Eagle and New Elk Mines may be found in Exhibit 8, in the Water, • <br />waste and Land analysis entitled "Hydr~~logy, Geology and water Quality <br />i.n the vicinity of the Maxwell and Allen Mines." <br />Processing Plant Recycling within the Flooded Workings <br />In 1995, Basin proposed to pump a 40 percent by weight slurry from <br />t:he thickener of the coal processing p1;3nt down the rock slopes into the <br />mine and extract an equivalent volume of water for use in the processing <br />plant. This process will result in a slight increase in the elevation <br />of the water level in the mine, through the deposit of the fines, and a <br />deterioration in the quality of the wager over time. <br />Data on flooding of the New E:Lk workings has been limited to <br />several probes of the workings through the East Portal air shaft since <br />December, 1993, and single probes of the Apache Canyon fan shaft and the <br />West Portal fan shaft. On 12/28/94, the water level was observed at <br />7065.2' in a hole drilled north of the Prep Plant and the Middle Fork of <br />the Purgatoire River, from which water will be recycled from the mine <br />(NEW-4). This elevation corresponds with flooding of the 286 acres of <br />mains with 5.7 x 108 gallons of water. <br />The slurry recycling project will maintain water quality of the <br />workings at concentrations which meet Colorado Ground water Quality • <br />Standards, assuming ideal mixing conditions within the mine. Basin will <br />pump as much as 700 gpm of slurry into the mine each year and 1.84 x 109 <br />gallons over the five-year life of the project. This is equivalent to <br />pumping in 2.43 x 108 gallons of water in the first year and 1.22 x 109 <br />gallons of water over the life of the project assuming that the slurry <br />is 34% solids by volume. <br />The middle member of the Raton formation, in which the coals are <br />found, consists of fine to medium grained sandstones interbedded with <br />siltstones and shales. A small number of water bearing zones within the <br />Paton are typically found in channel sandstone deposits of limited <br />horizontal extent. The Raton has not been developed for beneficial uses <br />extensively in the Stonewall/Weston area, due to the proximity of <br />shallow, alluvial waters along the Purgatoire River. <br />The Trinidad Sandstone has been identified as a regional aquifer. <br />It is located below the Lower Raton member and the Verrnejo Formation at <br />a depth of 500'-900' below the Allen seam. <br />Vertical communication between the overburden and the underburden <br />appears to exist, but to be limited. The observed mine inflows can be <br />attributed to the coal seam (Exhibit 8), and to faults intersected by the <br />mine. The Raton and Vermejo are fine grained sedimentary deposits which <br />(Revised 2/6/95) <br />2.05-H3 <br />