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MINING PLAN SBHIBIT D (cont.) GEOLOGIC SETTING ' The affected lands are located in the eastern part of the Eagle Valley Evaporite formation of Pennsylvanian age outcrops all along ' the Eagle River from a couple of miles downstream of Eagle to four or five miles upstream of Avon. In the immediate area of the river, the terrace, stream and outwash gravels are superimposed upon the I Eagle Valley Evaporite. These gravels are unconsolidated deposits of Pleistocene age. All or a major part of the gravels are probably 1 of glaciofluvial origin. Overlying the terrace gravels is a very 1 thin layer of soil. I Excavation depth at this location is not dependent on the thickness of the gravel but rather on B&B Excavatings desire to I keep the floor of the mined area 10 feet above the Eagle River. The sand and gravel will not be removed below a level 10 feet above the normal flow channel of the Eagle River. With this being the I case the gravel to be removed will range in thickness from 0 to approximately 40 feet. SOILS AND OVERBORDEN I There are five types of natural soil on the two parcels as determined by the Soil Conservation Service. All of these soils I ace very stony. They are designated as map units AW, 57C, 57 E, 62E and 69C see Map Exhibit I-1 for the locations of these soils. I Unit Aw, Fluvaquents, will not be affected by the mining operation because it is located below 6460 elevation in Stages 1 and 2. Units 57C and 57E are named Dahlquist- Southace complex and are I sandy loams and stony sandy loam s. Unit 62E is a Triden-Brownsto complex that is a moderately sandy loam. Unit 69C is named Yamac I Loam and is a light brownish gray loam. This unit is described as having very little gravel value, however on this site the surface I is intermixed with gravels and cobble. The loams are 25-458 cobble and gravel and will be exceedingly difficult to revegetate. 6