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Drill hole SC-3 indicates the presence of perched aquifers in the formation above the coal seams to be mined. Rock formations in the Bear No. 3 Mine area dip northerly toward the North Fork of the Gunnison River. The coal seams to be mined are at a higher elevation than the North Forth of the Gunnison River and are truncated by the Canyon of the North Fork of the Gunnison River. As a result, the coals and sandstones are drained. Water in the coals and sandstones above the coal seams to be mined appear to occur in perched systems which exhibit little lateral or vertical continuity. During the drilling of two exploration holes on the permit area, no water was reported to be encountered above the coal seams. Therefore, no thick, continuous aquifers containing any quantities of groundwater appear to be present above the coal seams to be mined. (ii) The bedrock aquifers have a low potential yield. The environment of deposition of bedrock in the region has a direct bearing on the hydrology of the area. During cretaceous time, an east-to-southeast prograding deltaic complex existed with • a variety of delta front and distributary mouth deposits with other deposits from a well-drained swamp, channel and upper deltaic plain environments. Many of the units are very lenticular and intertongued with each other and continuity of any of the units over large areas is rare except for the Rollins Sandstone. The Rollins Sandstone ranges from 120 to 200 feet thick and is extensive laterally. The Rollins Sandstone which is 40 to 50 feet below the B Seam is an identified regional aquifer. This formation ranges from 120 to 200 feet thick and is composed of massive, cliff-forming, locally cross-bedded, medium to coarse grained, buff to white sandstone. (iii) The quality of the water in the Rollins Sand- stone is tabulated on page 2.04-30hh. The quality and quantity of water from Springs G-26A and G-26B is presented on page 2.04-30ii. • 2.04-29a Rev. 11/30/93