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The region has a highland continental climate characterized by low precipitation, lazge <br />fluctuations in diurnal temperatures, low humidity, moderate wind, and high levels of insolation <br />(exposure to sunlight). The Craig area is in the rain snow shadow of mountain ranges to the west <br />and south and consequently has a high number of dry, clear days. <br />Local Climate <br />The climate of the Craig, Colorado area is chazacteristic of semi-azid steppe regions. The <br />average annual precipitation for the town of Craig, 5 miles north of Trapper, is 13.5 inches of <br />which over one-third is snowfall (averaging 66.5 inches/yeaz). Trapper Mine's average annual <br />precipitation is 16.7 inches. The mean annual temperature in Craig is 43°F, with recorded <br />extremes of-45°F and +100°F. Winds are predominantly from the west, but are locally <br />modified by topographic features. The growing season for the azea azound Craig averages 77 <br />frost-free days. <br />Soil Types <br />Three soil orders are found in the permit area: Aridisols, Entisols, and Mollisols. These soil <br />orders are characteristic of fairly steep, semi-arid regions of northwestern Colorado. They <br />represent soils that grade from recently developed soil bodies with minimum horizon <br />development (Entisols) to older soils with well-defined diagnostic horizons (Mollisols). <br />Soil Characteristics and Distribution <br />Overall, the soils found in the proposed permit area are relatively deep and fairly well-drained. <br />Effective rooting depth varies from two to sixty inches within the azea. The deepest soils <br />yielding the greatest rooting depths occur in valleys and on the leewazd sides of ridges. Soil <br />reaction is slightly acid to moderately alkaline over the permit area with the exception of <br />inclusions of small scattered areas with saline substrata. These small azeas have probably formed <br />in place from weathered sodic shales. <br />Control of Vegetation Distribution by Climate and Soils <br />Vegetation in the azea grows lazgely in response to macro-climatic influences of the region. The <br />north-facing slopes, having moderate to deep soils, a relatively mesic moisture regime, and <br />favorable levels of insolation throughout the year are characterized by well-developed mountain <br />shrub communities. On the colluvial toe-slopes, communities dominated by sagebrush and some <br />grasses occur. On the south-facing slopes behind the ridgeline of the Williams Fork mountains, <br />vegetative communities aze not as well-developed in terms of cover, density, and production due <br />to the less favorable soils, moisture regime, and increased solaz insolation. The trend in these <br />areas is towazd communities dominated by juniper, pinyon, mountain mahogany and xerophytes. <br />Trapper Mine 11 June 30, 2003 <br />