Laserfiche WebLink
United Companies, Inc. <br />March 21, 1994 <br />Page 4 <br />feet distance is the existing residence and out building on the <br />property which will be removed and an electrical line that feeds <br />the existing residence which will be used for the pit operation. <br />The existing electric line will be removed and relocated as the pit <br />progresses. The electrical line is an overhead line that extends <br />up the northeast side of the proposed gravel pit and along the <br />north side of the roadway along the north side of the pit. In <br />addition a telephone line exists along the north side. On the west <br />side a water and telephone exists between the property and U.S. <br />Highway 550. <br />The mining operation consists of a relatively shallow excavation to <br />remove the gravel layer to a depth of 25 to 30 feet. The drill <br />logs did not encounter the shale bedrock to the maximum depth <br />explored 25 feet. No water was encountered in the drill holes and <br />is not expected to be a factor in the pit operation. <br />The angle of repose is the angle from a horizontal plane that a <br />dry, loose cohesionless granular soil is stable. For the existing <br />granular material the angle of repose is on the order of 32 to 36 <br />degrees. The angle of repose can be considered equal to the angle <br />of internal friction when the soils are in a very loose condition. <br />However, the angle of internal friction increases with increased <br />density and is dependent on particle size, shape, gradation and <br />composition. The existing pit run material is medium dense to <br />dense. Thus, an internal friction angle on the order of 40 to 44 <br />degrees is reasonable for the pit run material. For a purely <br />cohesionless material the slope stability equation reduces to: <br />S.F.= tan 0 <br />taR lr <br />Where 0 = internal friction angle <br />i~ = angle of repose <br />Using the above formula for the pit run material at a slope angle <br />