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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 aeeas 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 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. Rechazge to the Rollins Sandstone occurs along <br />outcrops and along subcrops beneath the alluvium of Terror Creek to the east and Steveti s Gulch <br />to the southwest. However, due to the steepness of the topography in the outcrop aeeas (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 />percolation of snowmelt and precipitation downward through fractures. While no site-specific <br />aquifer chazacteristics for this unit are available from the permit area, 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 are 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 [o 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 has progressed below East Roatcap Creek and mine inflows have increased but still <br />remain insignificant to the local hydrologic regime. <br />Inflows from faults and fractures located outside stream valleys (such as in the Bowie No. 1 <br />Mine) generally dry up with time or flow intermittently at discrete points along the fault or <br />fracture. Those which continue to flow have flow rates which diminish to a trickle. Such <br />inflows may represent the dewa[ering of lenticular sandstone units with limited recharge areas, or <br />may represent flows through fracture zones extending to the surface which have narrow recharge <br />zones on steep slopes. <br />Surface Water- <br />Surface water information may be found in Volume 1, pages 42 to 47 of Section 2.04, pages 114 <br />to 135 of Section 2.05.6, and in Volume 4. Water rights tabulations and an augmentation plan <br />are found in Volumes 5 and SA. Annual hydrologic reports have been prepared since 1982 and <br />exist as stand- alone volumes. For a description of the surface water hydrology of the mine <br />permit area and a discussion of the impacts of mining on surface water, please refer to the <br />Hydrologic Balance and Probable Hydrologic Consequences portions of Section B of this <br />document. <br />15 <br />