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mg/l range. Spoil leachate is an alkaline calcium-magnesium sulfate type water, with total <br /> dissolved solids in the 2,600 to 4,300 mg/1 range. <br /> Bedrock hydrostratigraphic units in the vicinity of the PSCM permit area are likely recharged by <br /> meteoric waters wherever a significant quantity of snowmelt or rainfall accumulates on bedrock <br /> outcrops at high elevations around the perimeter of the Hayden Syncline. The water seeps into <br /> the rock through intergranular porosity and fractures. Immediately down dip from a recharge <br /> area, the bedrock is under water table conditions. From a recharge area, bedrock groundwater <br /> flows under the force of gravity generally down dip, toward the deeper part of the Sand Wash <br /> Basin (or Twentymile Park east of the permit area)where the ground water is under confined <br /> conditions. The hydraulic pressure at a location in a basin is determined by the height of the <br /> recharge areas above that location and the proximity to discharge areas. Bedrock units discharge <br /> ground water at low elevations in a basin wherever the units crop out or have a subcrop <br /> underneath the younger colluvium and alluvium. The dissolved solids content of ground water <br /> in bedrock units generally increases basinward from the recharge areas. <br /> The potentiometric surface of ground water in the confined portions of the bedrock units slopes <br /> generally basinward. Local relief on the potentiometric surface likely mimics the overlying <br /> topography, with potentiometric highs and lows roughly coinciding with the overlying highs and <br /> lows of the land surface. The alluvium of Grassy Creek and Fish Creek, and their tributaries, is <br /> either directly recharged by stream flow or discharges to stream flow, depending on stream flow <br /> level. The alluvial aquifers likely contribute to stream baseflow during dry periods. <br /> Natural Sprin&s <br /> The permit application contains information on natural springs in Section 2.04.7, Map 2.04.7 <br /> M2, and Table 2.04.7-T7.2. In addition to spoil springs, an inventory of natural springs and <br /> seeps within and adjacent to the PSCM permit boundary identified and sampled nine springs, <br /> seven of which have adjudicated water rights. Flows sampled were less than 5 gallons per <br /> minute and TDS ranged from 430 to 2920 mg/1 range. <br /> Surface Water <br /> Surface water hydrology information can be found in Section 2.04.5 of the permit application. <br /> The information includes baseline data collected in 2008 and 2009. Of approximately 10,164 <br /> acres in the PSCM permit area, 9,361 acres are in the Grassy Creek drainage basin and 803 acres <br /> are in the Fish Creek drainage basin. Grassy Creek and Fish Creek are perennial streams that are <br /> tributaries of the Yampa River. Grassy Creek has intermittent or ephemeral tributaries in the <br /> PSCM permit area that include Little Grassy Creek, Annand Draw, and Scotchman's Gulch. <br /> Fish Creek has an intermittent tributary in the PSCM permit area, Cow Camp Creek. <br /> Grassy Creek flows into the Yampa River approximately two miles north of the PSCM permit <br /> boundary. Fish Creek flows into Trout Creek approximately six miles east of the PSCM permit <br /> boundary. Trout Creek flows into the Yampa approximately five miles north of the Fish Creek/ <br /> Trout Creek confluence. <br /> 6 <br />