GENERAL35604 - Laserfiche WebLink

Home Browse Search

• -9 trapped or temporarily stored. This situation is somewhat modified by the presence of landslide complexes which occur throughout the general area 1n the Bowie and five adjoining quadrangles (Colorado 6eologlcal Survey information Series 5, 34p, ), Ground water will tend to move down through the more permeable material and along lateral shears of these landslide complexes. The sources of ground water discharges from the Steven's Gulch alluvium at the well field are through the applicant's wells. through underflow within the alluvium down the old bedrock channel of Steven's Gulch, and through discharges to the stream during high water table conditions in spring and early summer. Water quality analysis for the Steven's Gulch well water indicates good quality water, with none of the parameters exceeding the recrnmended standards of the U. S. Public Health Service. Alluvial/colluvial deposits in the Terror Creek drainage near the Morrell Cow Camp are also being utilized for water supply purposes. However, no impact is predicted for these areas since lands affected by mining lie to the south and east. Occurrences of ground water 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 only potential regional aquifer in the area is the continuous Rollins sandstone, located stratigraphically approximately 200 feet below the °0' coal seam, Recharge to the Rollins sandstone occurs along outcrops and along subcrops beneath the alluvium of Terror Creek to the east and Steven's Gulch to the southwest. However, due to the steepness of the topography 1n the outcrop areas (i,e. sandstones are cliff formers) and the narrowness of the stream valleys, the Rollins sandstone receives little recharge. Sane recharge to this continuous unit mdy come directly from the percolation of snowmelt and precipitation downward through fractures. Mhile no site-specific aquifer characteristics for this unit are available from the permit area, indications are that saturated portions of the Mesa Yerde Formation are not good aquifers (pages 33-37, Section 2.04.7, Yolume 1), Ground water occurrences in the stratigraphic interval of the Mesa Verde Formation above the 'D° seam are a furction of the depositional environment and are characterized by saturated horizons of localized lateral and vertical extent, separated by low porosity, unsaturated intervals. These saturated horizons do not appear to contribute significantly to overall regional ground water flow.