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Description of the Environment <br />The 20-acre permit area is situated on a moderately steep (approximately 15~ <br />slope) colluvial deposit between State Highway 133 and the flood plain of the <br />North Fork of the Gunnison River, at an approximate elevation of 5,900 feet. <br />The surrounding area is mountainous, with elevations ranging up to 8,300 feet <br />at the summit of Jumbo Mountain, to the southeast of the permit area. The <br />North Fork. in the vicinity of the permit area, has the appearance of a <br />moderately broad alluvial valley, extending to approximately 1,500 feet wide. <br />The valley separates high table lands south of the river from the slopes of <br />the Grand Mesa to the north. <br />The climate of the region is typical of the Rocky Mountain area. The valley <br />is semi-arid with annual precipitation averaging about 15 inches per year. <br />The May-September precipitation is 5 inches for the lowlands and 13 inches for <br />the mountain peaks. Temperature extremes at Paonia have ranged from -28oF <br />in January to 100°F during July and August. The average annual temperature <br />is approximately 49oF. Snowfall averages 58 inches per year. <br />The permit area is drained by the North Fork of the Gunnison River and one <br />unnamed ephemeral drainage which crosses the western portion of the permit <br />area. Water in the North Fork is characterized as a calcium bicarbonate type <br />with moderate levels of sulfate. <br />The flood plain of the North Fork, immediately to the south of the permit <br />area, has been found to meet the geomorphic criteria and irrigation <br />requirements of an alluvial valley floor (AVF). <br />Rock strata exposed on the steep slopes to the north of Highway 133 adjacent <br />to the site are sandstones and shales of the Upper Cretaceous Mesa Verde <br />Formation. Bedrock underlying the permit area is the Upper Cretaceous Mancos <br />Shale Formation. A colluvial deposit in excess of 50 feet thick overlies the <br />Mancos within the permit area and consists of an unconsolidated mixture of <br />large, angular shaped boulders, and rocks and cobbles of various sizes. <br />Quarternary age alluvial deposits occur within the flood plain--terrace <br />complex of the the North Fork in the vicinity of the loadout. <br />Near surface ground water is present in the alluvial aquifer within the <br />present flood plain of the North Fork to the south and topographically below <br />the permit area. No ground water exists within the colluvium upon which the <br />loadout has been constructed. <br />Soil sampling conducted by the applicant has indicated a clay loam soil with <br />poor horizonal development overlying unconsolidated colluvial parent material <br />at an average depth of 11 to 13 inches. <br />The primary Land use in tfie valley is irrigated agriculture, underground coal <br />mining, and wildlife habitat. Orchards and pasture land are irrigated via the <br />Fire Mountain Canal, which diverts water from the North Fork of the Gunnison, <br />and the Deer Trail Ditch, which diverts water from Hubbard Creek. Irrigation <br />water at Terror Creek is supplied by the Deer Trail Ditch, which flows by <br />culvert over the Fire Mountain Canal near the northern permit boundary. The <br />pre-disturbance land use at the loadout was irrigated orchard. <br />-4- <br />