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-5- The truck scale facility, located in tF,e North Fork Valley approximately 2 miles west of the confluence of Bubbard Creek with the North Fork of the Gunnison River,is at an elevation of 5,900 feet and is on essentially flat ground (0 to 5~ slope). The coal to be mined is located in the Somerset Coal Field. The rocks exposed in the Somerset Coal Field consist of the Mancos Shale and the coal-bearing Mesaverde Formation of Upper Cretaceous Age; and the Ohio Creek Conglomerate, the Wasatch Formation and the Quartz monzonite por- phyry of Early Tertiary Age. (See Strati graphic Cross Section, page 19 of this document). Coal is to be produced from the Mesaverde Formation, a 2,500 foot thick sequence of sedimentary strata overlain by the Ohio Creek Conglomerate and underlain by the nlancos Shale. Beds exposed in the mine area dip 3-5 degrees north-northeast. The Blue Ribbon Pfine caill extract coal from the "E" seam, of the Upper Coal Member of the Mesaverde Formation. The Upper Coal member ranges from 900 - 600 feet thick in the Somerset Coal Field and bears four minable coal seams. The member consists of interbedded sandstones, siltstones and coals, and is underlain by a massive sandstone 25 to 225 feet thick which overlies the "C" seam and marks the top of the Lower Coal member. The "E" seam overburden ranges from less than 20 feet near the western edge of the Blue Ribbon mine permit area to over 1,400 feet in eastern portions of the permit area. Three categories of potential aquifers exist in the general area: alluvial deposits associated with the North Fork of the Gunnison River and its trib- taries; the Rollins sands tone. and lenticular, discontinuous sandstones of the upper hlesaverde Formation. The largest and rrost useful alluvial deposits found in the region are associated with the North Fork of the Gunnison River. Smaller, more isolated alluvial deposits are associated with several of the other tributaries of the North Fork. Directly adjacent to the Blue Ribbon hfine along Nubbard Creek is a small alluvial deposit into which Blue Ribbon Coal Company has completed a well for sanitary and industrial purposes. The Rollins sandstone is the only sandstone with sufficient porosity and lateral extent to be considered a regional bedrock aquifer. This sandstone outcrops one mile south of the Blue Ribbon Mine in a narrow reach of the Nubbard Creek Stream valley. The only wells in the region which are completed in this aquifer are located near the Hawk's Nest dfine along the North Fork of the Gunnison. Localized perched bedrock aquifers exists in the discontinuous, lenticular, 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 (sec- ondary porosity) and the topography of the recharge area. No known wells are completed in the sandstones of the upper Mesaverde Formation above the mine workings. .