2003-01-27_GENERAL DOCUMENTS - C1981022

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and lenticulaz sandstones, siltstones and coals, and is overlain by a massive sandstone 25 to 225 feet thick which lies directly on the C seam and mazks the bottom of the upper coal member. Three categories of potential aquifers exist in the general area: alluvial deposits associated with the North Fork of the Gunnison River and its tributaries, the Rollins Sandstone, and lenticulaz discontinuous sandstones of the Upper Mesaverde Formation. The largest alluvial aquifers are associated with the North Fork of the Gunnison River. Smaller, more isolated alluvial aquifers are associated with several tributaries of the North Fork. The Rollins Sandstone is the only known sandstone with sufficient porosity and lateral extent to be considered a regional bedrock aquifer. The only wells in the region which aze completed in this aquifer are located neaz the Hawk's Nest Mine along the North Fork. Localized perched bedrock aquifers exist in the discontinuous, lenticulaz, fine-grained sandstones of the Upper Mesaverde Formation. The amount of ground water in these sandstones is controlled by faulting and fracturing of the strata (secondary porosity) and the topography of the rechazge azea. No known wells are completed in the sandstones of the Upper Mesaverde Formation above the mine workings. The valley in which the towns of Paonia and Somerset are situated is semi-arid, with annual precipitation averaging about 15 inches per yeaz. Mean annual precipitation increases with elevation, reaching over 40 inches per year neaz the summit of Mt. Owen. The May-September precipitation is five inches for the lowlands and 13 inches for the mountain peaks. This indicates that snowfall patterns play an important part in determining the hydrologic conditions of the area. Temperature extremes at Paonia have ranged from -28°F in January to 100°F during July and August. The average annual temperature is approximately 49°F. Snowfall averages 58 inches per yeaz. The general azea in which the Sanbom Creek Mine is located is characterized by steeply sloping mountains covered either with tall shrub vegetation dominated by oakbrush and serviceberry, or stands of pinon and juniper trees. Drainages in the area aze lined with ripazian vegetation communities along the stream banks. Some of the more level azeas have been cleazed and support limited livestock grazing; however, for the most part, the surrounding land is undeveloped and is used primazily as wildlife habitat. Recreational activities such as big game hunting, trapping, fishing, and off-road driving also occur in the general azea. The Elk Creek portal facilities aze approximately a half mile up the Elk Creek canyon from the town of Somerset and are located at the contact of the alluvium of the North Fork and steep upland sedimentary formations. Sanbom Creek Tract portal facilities aze just east of Sanbom Creek or approximately one mile east of the town of Somerset.