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alluvial deposits of Quaternary age are also found near the mine in the valleys of the Yampa and Williams Fork Rivers as well as in several ephemeral stream drainages on the mine property itself. The Williams Fork Formation is stratigraphically subdivided into three units or members. These are, in ascending order, the lower Williams Fork, the Twenty Mile sandstone, and the upper Williams Fork, with individual thicknesses of 920'', 100' and 680' respectively. The coal seams being developed at Trapper Mine, designated H, I, L, Q, 0 rider, Rand R rider, all lie within the upper Williams Fork member. Structurally, the mine is situated on the south limb of the northwest plunging Rig Bottom syncline. There are no major faults identified within the area of the mine. Trapper Mine is situated primarily on the north slope of the drainage divide between the Yampa River and a major Yampa River tributary, the Williams Fork P.iver. Drainages within and adjacent to the permit area (on the north-facing slope) run south to north down the slope and are dendritic in pattern. Within the permit area are portions of the following drainages: Coyote, •!o Mame, Johnson, Pyeatt, Buzzard and Flume. These drainages flow primarily in response to snowmelt and/or heavy rains. All of these drainages discharge eventually into the Yampa River. There is also a small portion of the southern part of the permit area which drains southward to the Williams Fork River. There drainages include parts of the upper portions of Ute, Caster, Deer, Elk and Horse Gulches. Within the general area of the Trapper Mine, ground water exists in both bedrock and alluvial aquifers. Significant bedrock aquifers are the Trout Creek, Middle, Twentymile, and White sandstones. The Middle, Twentymile and White sandstones lie within the Williams Fork Formation; the Trout Creek sandstone is the uppermost member of the underlying Iles Formation. The major alluvial aquifers in the area are associated with the Yampa and Williams Fork Rivers. Many of the bedrock coals, discontinuous sandstones, and siltstones and some of the smaller alluvial bodies in the area of the mine are also water bearing. These, however, characteristically contain insufficient quantities of water to be considered significant aquifers. The climate of the region is classified as highland continental, and is characterized by low precipitation, large fluctuations in diurnal temperatures, low humidity, moderate wind, and high levels of insolation (exposure to Sunlight). The local climate of the Craig, Colorado area is characteristic of the semi-arid steppe regions. Due to massifs to the west and east of the Craig area and the corresponding topographic effects, this locale experiences a high number of dry, clear days. The average annual precipitation for the area is 13.5 inches, of which over one-third is snowfall (averaging 66.5 inches/year). The mean annual temperature is 43°F, with recorded extremes of -45°F and +100°F. Winds are predominantly from the west, but are locally modified by geomorphic features. The growing season for the area around Craig averages 77 days. The permit area is occupied by three soil orders; Aridisols, Entisols, and Mollisols. These soil orders are characteristic of fairly steep, semi-arid -~-