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The Dakota coal has been described as an aquifer. Wells completed in the Dakota show water level <br /> fluctuations of 1.3 to 14.6 feet. The water table exhibits seasonal fluctuations with high water levels <br /> in late fall. The aquifer is recharged from the east north east and discharges to the west and along <br /> Calamity Draw. The transmissivity varies from 0.92 to 6.0 Oday, based on hydraulic conductivity <br /> values of 0.04 to 0.34 ft/day (average values of 0.19 ft/day), reflecting moderate flow capabilities. <br /> The water quality of the Dakota coal is unacceptable for most uses. The saline, sulfate-based water <br /> has TDS levels varying from 1050-4444 mg/l, averaging 2822 mg/l at New Horizon Mine. Three <br /> wells at the New Horizon Mine 2 exhibit two distinct geochemical characteristics. Two wells have <br /> calcium/magnesium sulfate water with the pH averaging 5.4. One well, 17-P1, is an alkaline sodium <br /> sulfate water with the pH averaging 9.2. Iron, manganese, aluminum, fluoride and pH levels exceed <br /> recommended water quality criteria for agricultural use,and concentrations of aluminum and fluoride <br /> exceed recommended water quality criteria for livestock. <br /> The aquifer underlying the coal is identified as the underburden aquifer. The wells in the underburden <br /> have been completed 17 to 64 feet below the coal,and samples are representative of water within the <br /> lower Dakota Sandstone. This confined aquifer is recharged along the Uncompahgre Plateau to the <br /> northeast and discharges towards the southwest. Transmissivity was measured at six sites and varies <br /> from 3.0 to 88 ftZ/day,averaging 38 ft-/day. Hydraulic conductivity values varied from 0.07 to 4.5 <br /> ft/day, averaging 1.6 ft/day. This aquifer is not used locally to any great extent. <br /> The water in the underburden is characterized as a hard, moderately alkaline saline water with high <br /> sulfate concentrations (average sulfate concentrations of 695 mg/1). Two wells show a <br /> calcium/magnesium sulfate type water while one well shows an alkaline sodium bicarbonate type <br /> water. The TDS varies from 960-2648 mg/l, averaging 1619 mg/1. Dissolved iron levels vary from <br /> 0.02 to 2.51 mgll and average 0.63 mg/l. The sodium bicarbonate well occasionally exhibits pH levels <br /> which exceed the recommended agricultural standard. Another well shows manganese levels which <br /> exceed the agricultural standards. Ail wells meet the recommended water quality standards for <br /> livestock watering. The underburden aquifer does not produce acceptable water for domestic <br /> purposes: TDS, sulfate and ammonia standards are exceeded. <br /> Ground water within 150 feet of the ground surface has been only minimally developed for use in the <br /> Nucla area. High salinities and occasionally high sodium or sulfate concentrations preclude its use <br /> as domestic, agricultural or stock water. In addition, moderate hydraulic conductivities are coupled <br /> with low sustained well yields (less than 1.5 gptn), discouraging sustained dependence on wells <br /> completed within these aquifers. T <br /> Lou K ZT- Gw L,'-� �. <br /> Soils <br /> There are three major soils types at the New Horizon Mine 2 area (see Soils Map of the permit <br /> application): Progresso-Bond Complex, 2 to 15 percent slopes; Barx sandy loam, 1 to 4 percent <br /> slopes; and Haplaquolls, I to 3 percent slopes. <br /> The Progresso-Bond complex is comprised of 40 percent Progresso, 40 percent Bond, 10 percent <br /> Barx (see below), 5 percent Travesilla, and 5 percent Bowdish series soils. The Progresso series is <br /> classified as a fine-loamy,mixed, mesic,Ustollic Haplargid. The Bond series is a loamy, nixed, mesic <br /> 7 <br />