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portals and 1,500 feet lower in elevation. Significant alluvial sand and gravel deposits averaging <br /> 34 feet thick exist along the North Fork from the mouth of Terror Creek to the confluence of the <br /> Gunnison River. There are numerous wells in the area which draw water from this alluvium; well <br /> yields range from 5 gallons per minute (gpm) to 120 gpm, with average yields of approximately <br /> 17 gpm (Section 2.04.7, Volume 1). <br /> Stevens Gulch, an ephemeral stream located in the center of the permit area, drains an area of six <br /> square miles and contains several reaches of shallow alluvium/colluvium. Most of these reaches <br /> have little groundwater except during periods of stream flow. The most significant area of <br /> alluvium/colluvium occurs in the NW'/4 of Section 13, Township 13 South, Range 92 West <br /> (Stevens Gulch wellfield), where a 25-foot-thick sandstone outcrop has created a topographic <br /> restriction such that a considerable thickness of alluvial sands and colluvial material has been <br /> deposited. Test wells drilled by the BRL indicate that the alluvium in this area can support a <br /> pumping rate of approximately 28 gpm (Groundwater Hydrology Appendix, Volume 4). BRL <br /> installed a production well and used this water for domestic use, dust control, and fire control. <br /> The recharge to the Stevens Gulch well field area is through flow from the adjacent colluvial <br /> deposits and from a leaky pipeline aqueduct. The groundwater 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 /> area in the Bowie and five adjoining quadrangles(Colorado Geological Survey Information Series <br /> 5, 34p.). <br /> Groundwater will tend to move down through the more permeable material and along lateral shears <br /> of these landslide complexes. The sources of groundwater discharges from the Stevens Gulch <br /> alluvium at the well field are through the BRL's wells, through underflow within the alluvium <br /> down the old bedrock channel of Stevens Gulch, and through discharges to the stream during high <br /> water table conditions in spring and early summer. <br /> A water quality analysis for the Stevens Gulch well water indicates good quality water,with none <br /> of the parameters exceeding the recommended standards of the Colorado Department of Public <br /> Health and Environment. <br /> Alluvial/colluvial deposits in the Terror Creek drainage near the Morrell Cow Camp are also being <br /> utilized for water supply purposes. However, no impact is predicted for these areas since lands <br /> affected by mining lie to the south and east. <br /> Occurrences of groundwater 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 area. 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 Stevens Gulch <br /> to the southwest. However, due to the steepness of the topography in the outcrop areas (i.e., <br /> sandstones are 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 /> 9 <br />