1981-08-20_GENERAL DOCUMENTS - C1981038

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-b- 2.04.21 Geologic Log of Stevens Gulch Well #2 on page 39, Section 2.04 of Volume 8. This depletion of flow, which could eventually reach the North Fork ^� and affect downstream water rights, has been mitigated by the applicant via an approved augmentation plan decreed in the Division 4 Water Court. Augmen- tation is accomplished by releasing water from a water right held in East Beck- with No. 1 Reservoir, located in the Anthracite drainage. See the Augmentation sections of the Ground Water appendix in Volume 2. Well records from the State Engineer's Office indicate that only one other well is completed in materials overlying the "D" seam and downdip of the proposed life of mine area. This well is .located in the W NW; Section 6, T13S, R91W and draws 6 gpm from a 32 ' well. The source of water for this well appears to be from an area of colluvium to the South of the well. Water quality analysis for the Stevens Gulch well water indicates good quality water, with non-e of the parameters exceeding the recommended standards of the U.S. Public Health Service. The only ,treatment necessary is chlorination, as required by the Colorado Department of Health for public drinking water supplies. The recharge to the Stevens Gulch alluvial well field area is through flow from the adjacent colluvium (see Map 44) and from a leaky pipeline aqueduct (see Map 43, Volume 6) . The groundwater flows through the colluvium downslope to the alluvium, where it becomes trapped or temporarily stored. This situation is somewhat modified by the presence of landslide complexes which occur throughout the general area, as can be seen from the Colorado Geologic Survey's mapping of the geologic hazards in the Bowie and 5 adjoining quadrangles (Colorado Geologic Survey Information Series 5, 34p.) . Groundwater will tend to move down through the more permeable material and along lateral shears of these landslide complexes. The sources of groundwater discharges from the Stevens Gulch alluvium at the well field are through the applicant's wells, through underflow within the alluvium down the old bedrock channel of Stevens Gulch, and through discharges to the stream during high water table conditions in Spring and early Summer. Terror Creek is believed to have alluvial aquifers that could be developed for water supply purposes, e.g. , North of the permit area in the Morrell Cow Camp area. However, no detailed analysis of this alluvium has been made by the applicant due to it's remoteness to the permit area (see Map 43, Volume 6) . Occurences of groundwater have been noted in the Mesa Verde Formation from information obtained from drilling, experience in the mine and from the presence of springs and seeps in the permit area and hydrologically adjacent area. This information indicates that the onlu potential regional aquifer in the area is `I`9 Rollins Sandstone, located strati graphi call u approximately, 200 'eet belo-w the "D" coal Sea.:.. Recharge to the Rollins Sandstone would occur c_ 7er_cr Creek to the Fast and Stevens Gulch to the southwest. However, due to the steepness of the topography in the outcrop areas (i.e. sandstones are cliff formers) and the narro,N-ness of the stream rallec:s, the Rollins Sandstone receives little recharge. Sc,me recharge to this continuous unit' comes directly from the percolation of snowmelt and precipitation downward through sands and along fractures. No