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The rechazge to the Steven's Gulch well field azea is through flow from the adjacent colluvial <br />deposits and from a -eaky pipeline aqueduct. The ground water flows through the colluvium <br />downslope to the alluvium, where it becomes trapped or temporarily stored. This situation is <br />somewhat modified by the presence of landslide complexes which occur throughout the general <br />azea in the Bowie and five adjoining quadrangles (Colorado Geological Survey Information <br />Series 5, 34p.). <br />Ground water will tend to move down through the more permeable material and along lateral <br />shears of these landslide complexes. The sources of ground water dischazges from the Steven's <br />Gulch alluvium at the well field aze through the applicant's wells, through underflow within the <br />alluvium down the old bedrock channel of Steven's Gulch, and through discharges to the stream <br />during high water table conditions in spring and early summer. <br />Water quality analysis for the Steven's Gulch well water indicates good quality water, with none <br />of the parameters exceeding the recommended standazds of the Colorado Department of Public <br />Health and the Environment. <br />Alluvial/colluvial deposits in the Terror Creek drainage near the Morrell Cow Camp are also <br />being utilized for water supply purposes. However, no impact is predicted for these areas since <br />lands affected by mining lie to the south and east. <br />Occurrences of ground water have been noted in the Mesaverde Formation from information <br />obtained from drilling, experience in the mine and from the presence of springs and seeps in the <br />permit area and hydrologically adjacent azea. This information indicates that the only potential <br />regional aquifer in the area is the continuous Rollins Sandstone, located stratigraphically <br />approximately 200 feet below the D coal seam. Recharge to the Rollins Sandstone occurs along <br />outcrops and along subcrops beneath the alluvium of Terror Creek to the east and Steven's Gulch <br />to the southwest. However, due to the steepness of the topography in the outcrop areas (i.e. <br />sandstones aze cliff formers) and the narrowness of the stream valleys, the Rollins Sandstone <br />receives little recharge. Some recharge to this continuous unit may come directly from the <br />percolation of snowmelt and precipitation downward through fractures. While no site-specific <br />aquifer characteristics for this unit are available from the permit azea, indications aze that <br />saturated portions of the Mesaverde Formation are not good aquifers (pages 33 to 37, Section <br />2.04.7, Volume 1). <br />Ground water occurrences in the stratigraphic interval of the Mesaverde Formation above the D <br />seam are a function of the depositional environment and aze characterized by saturated horizons <br />of localized lateral and vertical extent, separated by low porosity, unsaturated intervals. These <br />saturated horizons do not appear to contribute significantly to overall regional ground water flow. <br />To date, the Bowie No. 1 Mine has experienced maximum inflows of around 1,500 gpd. This <br />inflow came from both the floor and roof and were generally roof drips or wet areas on the floor. <br />Mining progressed below East Roatcap Creek and mine inflows have increased but still remained <br />insignificant to the local hydrologic regime. The portals of the East Mine were sealed in 2001 <br />and the portals at the West Mine were sealed in 2000, so no recent mine inflow information is <br />available. <br />15 <br />