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Mesaverde strata which dip 45 to 60 degrees to the southwest in the permit azea. As a result of <br />the resistant sandstones, surficial topography in the permit area is characterized by steep slopes <br />(30 to 50 percent) and high gradient ephemeral drainages. A narrow band of unconsolidated <br />deposits occurs along Harvey Gap Drainage. Channel erosion has dissected the unconsolidated <br />materials to a depth of up to 80 feet in the permit azea. <br />The permit area is drained by Harvey Gap, which, due to seepage from the Grass Valley <br />Reservoir located upstream from the mine, is a perennial stream through the permit area. <br />Harvey Gap is utilized as a conduit for irrigation flows from the reservoir to a system of <br />irrigation canals along terraces of the Colorado River to the south of the permit azea. The <br />terrace currently supporting irrigated agriculture approximately 'fz mile south of the permit azea <br />has been identified as an alluvial valley floor. Ground water occurs in the lensaic sandstones of <br />the Mesaverde Formation. The sandstones pinch out laterally in both directions from the mine <br />site, and have been identified as potential aquifers within the permit area. <br />The climate in the permit azea is semi-arid with a mean annual precipitation of 11 inches. <br />Soils in the permit azea aze rocky and poorly developed on the steep valley side slopes, and are <br />classified as residual Torrienthents. Deeper, more well developed clayey to loamy soils derived <br />from colluvial and alluvial material are present along the tce slopes and valley bottom. Soils in <br />the immediate vicinity of the Eastside Mine have been disturbed by previous coal mining activity. <br />Portions of the permit area have been disturbed to the extent that only weedy annual vegetation <br />persists. Vegetation along the valley bottom is dominated by a dense cover of big sagebrush <br />(Artemisia tridentata) with an understory of cheatgrass (Bromus tectorum) and yellow sweetclover <br />(Mellotus o~icinalis). A juniper woodland community occurs on the steep valley sideslopes on <br />both sides of Harvey Gap. <br />Land use in the immediate vicinity of the permit area is undeveloped land and wildlife habitat. <br />Irrigated agriculture is an important land use along the terraces to the south of the Grand <br />Hogback. <br />The operations proposed by Eastside Coal Company consisted of room and pillaz and continuous <br />underground mining extracting up to 200,000 tons of coal per yeaz from the E coal seam. <br />However, operations never got beyond the development stage. <br />The Eastside Mine has water rights for a total of 10 acre-feet/yeaz from Ruedi Reservoir. <br />Consumptive use included domestic, dust suppression, evaporation, irrigation, and cooling water. <br />The entire 12-acre permit area has been disturbed in varying degrees by previous mining activity. <br />Sufficient soil was to have been stripped to provide a minimum replacement depth of six inches <br />on disturbed azea. <br />Sediment and drainage control consisted of diversion ditches and sediment ponds at the mine <br />portal/yard area. Sediment control for the three-acre office/shop azea will be achieved by <br />vegetation, gravel surfacing and filter fabric dams. <br />3 <br />