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Upland terrace deposits are found sporadically throughout the permit area, <br />where they have not been eroded off. They can achieve thickness of seventy <br />(70) feet thick within the permit area. A perched aquifer in one of these <br />deposits has produced a spring in Section 22, T9N, R78W which has an average <br />flow of less than 2 gpm. This spring is located outside the area of proposed <br />mine disturbance. <br />Alluvium is found in places along all of the draws draining the mine site, <br />along the Canadian River and along the Illinois River adjacent to the <br />loadout. The alluvium within the draws is predominately composed of clay with <br />isolated sand and gravel lenses. Wells have been strategically placed to <br />intersect these lenses. To date, the calcium bicarbonate water quality does <br />not appear to have been modified by the mine. There are currently no wells <br />along the Canadian River alluvium east and northeast of the mine. <br />The alluvium along the Illinois River near the loadout is less than 25' <br />thick. Underflow is estimated at 1.5 acre-feet/day on material whose <br />permeability is estimated to be 2500 gpd/f t2. The water quality was <br />initially characterized as a calcium bicarbonate water with small <br />concentrations of iron, magnesium sulfate and nitrates, and TDS of <br />It currently is a magnesium or sodium bicarbonate water with a TDS of <br />Surface Water <br />The general area which includes the mine plan area is drained by the Canadian <br />River, a perennial stream that flows northward into the North Platte River at <br />Northgate, Colorado. The Canadian River drains 114 square miles between USGS <br />Stations 06619400, upstream of mining activities, and 06619450 downstream of <br />mining activities. The drainage area between these two monitoring stations <br />includes the Marr Mine plan area, other abandoned and reclaimed mines, and <br />various agricultural enterprises. The agricultural usages of land surrounding <br />the mine plan area are primarily unirrigated rangeland. Lands immediately <br />paralleling and of varying widths along the Canadian River have been <br />classified meadowland. A portion of the meadowland is cropped for hay. This <br />land is not shown precisely as various acreages in each catagory. Along the <br />Draws downstream from the permit area, there are no indications that this area <br />is used for anything but rangeland. The Canadian River has a recorded average <br />base flow rate of four (4) cfs. The recorded water flow rate has reached two <br />hundred (200) cfs during the snow melt-rainfall period. Most of the water <br />received in this river comes from snow melt in the Medicine Bow Range to the <br />east. Spring flooding decreases gradually in July and August to the base <br />level. <br />Canadian River water quality samples taken upstream of mining activities, USGS <br />Station 06619400, contain predominantly calcium and bicarbonate ions. Water <br />quality samples taken downstream from mining activity at USGS Station 06619450 <br />show slightly higher concentrations of magnesium, sulfate and nitrogen (NO2 <br />& NOB>. The nitrogen increases are attributed to agricultural practices in <br />the area. The permit application states that the higher concentrations of <br />magnesium and sulfate can be partially attributed to mining activities of the <br />area. Tables 13 and 14 of the permit application detail these water quality <br />data. <br />