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Probable hydrologic consequences envisioned upon first issuance and subsequent renewals of the permit (mining of the E-seam of coal in the Mesa Verde Formation) never materialized due to the premature closure of the mine. Probable hydrologic consequences are now considered negligible. The Grass Valley Reservoir is constructed on the relatively impermeable Mancos Shale Formation. The Eastside Mine is located downstream of the reservoir, in the overlying Mesa Verde Group. There is no apparent hydrologic communication between the mine and.the reservoir. Approximately''/x mile downstream from the mine, the Wasatch Formation lies beneath the floodplain of the Colorado River (in some cases overlain by as much as 100 feet of Quaternary alluvial deposits). There are numerous alluvial wells south of the permit azea along the Colorado River. Ground water communication between the mine (in the E-seam) and the alluvium fringing the Colorado River is probably precluded by the relatively impervious members of the Mesa Verde and Wasatch Formation. Potential aquifers in the mine area are found within the Iles Formation, Williams Fork Formation, Wasatch Formation, and the Colorado River alluvium south of the permit area. Relatively impermeable interbedded shales within the Mesa Verde separate the relatively permeable sandstone and coal units of the Iles and Williams Fork Formations. The sandstones are lenticular in nature, pinching out laterally in both directions from the mine site and are characterized as fine- to medium-grained, calcite cemented units. The low permeability of approximately 3700 feet of interbedded units effectively isolates the E-coal seam from shallow ground water south of the Grand Hogback. Three domestic wells have been completed in the shallow bedrock aquifers of the region. These wells have been drilled in the Upper Williams Fork Formation. One is located approximately 7 miles southeast of the mine site; another approxirrSately 3 miles to the southwest. Both of these wells, from the indicated depth of completion, appear to tap the uppermost sandstone units of the Williams Fork Formation, separated from the E-coal seam by numerous impervious layers. The remaining well is located approximately 22 miles southeast of the mine. This well has a total depth of 55 feet, and is separated from the E-coal seam by several hundred feet of low permeability units. Alluvial aquifer potential also exists along the Elk Creek Drainage north of the Grand Hogback. This alluvium is perched on Mancos Shales and is isolated from the coal seams at the Eastside Mine by this impermeable unit. The applicant completed two wells within the coal seams overlying the E Seam within the permit boundary. This in-seam water was typified as high in total dissolved solids (TDS), conductivity, and sulfate. The sodium adsorption ratio (SAR) was relatively low. The yields from these wells ranged from .023 gallons per minute (gpm) to .6 gpm. The applicant also sampled water that seeped into the portal area of the established mine. The quality of this water was more typical of fresh water and had little 13 03/06/00