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Water quality is generally poor. 6. Groundwater Groundwater within the ridges and above the drainages is expected to be minimal, and when present, will occur as perched water zones within porous and/or fractured sandstones and coals. The groundwater may drain out of the side slopes via springs in the deeply incised valleys. Potential aquifers of significance in the Mesaverde Group in Northwest Colorado include the Twenty Mile Sandstone of the Williams Fork Formation and the lower Trout Creek Sandstone of the Iles Formation. The Twenty Mile Sandstone is not as prominent or continuous in the proposed drilling areas as in other locations in northwest Colorado. The Trout Creek Sandstone is the major regional aquifer, and lies well below the target-drilling zone and outcrops west, south, and north of the proposed exploration reserve definition area. For additional information, please refer to the Colowyo Permit C-81-019. None of the proposed exploration holes will be developed as water wells. 7. Soils The soils resulting from weathering of the Williams Fork and Iles Formations are generally clay, silty clay, or silty looms. On ridge tops, the soil profiles range from about one to five feet in depth and are dark in color, containing a significant amount of decayed plant material. The underlying rock type governs the clay content of the soil. The shales and siltstones generally form clay and silty clay looms, while the sandstones form silt and silty clay looms. These soils have good water retention capability, and have proven to be suitable for reclamation/revegetation purposes. Steeper slopes form shallower soil profiles and contain a great deal of rocks and cobbles. Natural erosion is evident on steep slopes throughout the proposed area. The erosion is severe in gullies that channel concentrated flows of runoff and less severe where sheet flow occurs. Drainage bottoms contain deep well-developed soil profiles derived from the erosion of the swrounding highlands mentioned above. Soil profiles and other colluvial derived deposits found in the major drainage bottoms are typically tens of feet deep. N:\CCC_ENGUUAN\DMG\NOI DOC\06N01\06 N01 TextAOc 1027/05 4