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-I1- <br />The mast significant occurrence of ground water in the general area is <br />associated with the alluvium of the North Fork of the Gunnison River, <br />located approximately 2 miles southeast of the mine portals and 1,500 <br />feet lower in elevation. Significant alluvial sand and gravel deposits <br />averaging 34 feet thick exist along the North Fork from the mouth of <br />Terror Creek to the confluence of the Gunnison River. There are numerous <br />wells in the area which draw water from this alluvium, with an average <br />yield of 17.4 gpm. See Table 2.04.3 State Engineer's. Well Printout, <br />pages 56-57, Section 2.04, Volume 8. <br />Stevens Gulch, an ephemeral stream, located to the West of the permit <br />area, drains an area of 6.0 square miles and contains several reaches of <br />shallow alluvium. Most of these reaches have little ground water except <br />during periods of stream flow. The most significant area of alluvium <br />occurs in the NW 1/4 of Section 13, T13S, R92W, where a 25 foot thick <br />sandstone outcrop has created a topographic restriction such that a <br />considerable thickness of alluvial sands have been deposited by the <br />ephemeral flow. Test wells drilled by the applicant indicate that the <br />alluvium in this area can support a pumping rate of approximately 28 <br />gpm. The applicant has installed a production well and currently uses <br />this water for domestic use, dust control, and fire control. See Ground <br />Water Investigation of Stevens Gulch for Colorado Westmoreland Inc. and <br />Well Completion Report SG-2 in the Ground Water appendix of Volume 2, and <br />Figure 2.04.'2, Geologic Log of Stevens Gulch Well #2 on page 39, Section <br />2.U4 of Volume 8. <br />The recharye to the Stevens Gulch alluvial well field area is through <br />flow from the adjacent colluvium (see Map 44) and from a leaky pipheine <br />aqueduct (see Map 43, Volume 6). The ground water flows through tt <br />colluviwn downslope to the alluvium, where it becomes trapped or <br />temporarily stored. This situation is somewhat modified by the presence <br />of landslide complexes which occur throughout the general hazards in the <br />Bowie and 5 adjoining quadrangles (Colorado Geologic Survey Information <br />Series 5, 34p.). <br />Ground water will tend to move down through the more permeable material <br />and along lateral shears of these landslide complexes. The sources of <br />ground water discharges from the Stevens Gulch alluvium at the well field <br />are Through the applicant's wells, through underflow within the alluvium <br />down the old bedrock channel of Stevens Gulch, and through discharges to <br />the stream during high water table conditions in spring and early summer. <br />Water quality analysis for the Stevens Gulch well water indicates good <br />quality water, with none of the parameters exceeding the recommended <br />standards of the U.S. Public Health Service. <br />Terror Creek is believed to have alluvial aquifers that could be <br />developed for water supply purposes, e.g., North of the permit area in <br />the hlorrell Cow Camp area. However, no detailed analysis of this <br />alluvium has been made by the applicant due to it's remoteness to the <br />permit area (see Map 43N, Volume 6). <br />