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-4- The Twentymile Sandstone and lower lying Trout Creek Sandstone are aquifers of significant regional extent. Other ground water bearing zones occur in the coals and local lenticular sandstones within the mining area. Recharge areas for most of these strata are on the south facing slopes along the Williams Fork River Valley south of the mine. Ground water tends to flow along the dip of the strata (northeast) and some of the localized lenticular sandstones discharge in the form of springs north of the mine. Within the permit area are portions of the Hayden Gulch, Dowden Gulch and Dry Creek drainage basins. The majority of the mine area occurs within the Hayden Gulch drainage. These basins contain ephemeral streams which respond predominantly to spring runoff from snowmelt. Hayden and Dowden Gulch are tributaries to the Williams Fork River which is perennial in nature. The region is characterized by a semi-arid steppe climate regime. The prevailing wind is from the west and southwest and average annual precipatation if 16.1 inches. The growing season in the region varies from 28 days to 94 days; the time span depending greatly upon the elevation of a given area. Soils at the mine site are of the order mollisol and suborder boroll. These are soils formed in cool climates which are characterized by a very dark colored base-rich surface layer. Variability of the Characteristics of the soils on the permit area is primarily due to slope, aspect and topographic position. Deeper soils are located in the valley bottoms and footslopes while the shallower soils occupy the upslopes. Vegetation is also distributed in response to the micro-climatic influences of the north-south trending ridge and valley complex within the area. Sagebrush communities dominate the richer, deeper soils of the valley bottoms and gentle slopes. Oak communities dominate the generally drier south and west facing slopes in the area, and often intergrade into the other communities in the form of patches of dense oak growth. Aspen dominated communities are found in clumps in small hillside swales and gentle north slopes in the permit areas; these areas are characterized by a more mesic moisture regime and more fertile soils. The remaining mountain shrub can be subdivided into two distinguishable components; communities dominated by chokecherry, and communities dominated by serviceberry. Serviceberry communities are found dominating steep south facing slopes in the southern portion of the mine permit area. These areas are characterized by a relatively xeric moisture regime and poorly developed soils receiving large amounts of high intensity solar radiation. Chokecherry communities are found on the gently sloped hill tops in the area. These communities intergrade with the aspen, sage, and oak communities. The load-out lies at an elevation of approximately 6400 feet on the bottomland of an alluvial valley. The area to be permitted is 134 acres which includes the railroad loop. land use surrounding the load-out is primarily agriculture and grazing. The valley contains the Dry Creek drainage, an ephemeral stream, which is a tributary of the perennial Yampa River.