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<br />FIELD INVESTIGATION <br />Soil Slopes <br />Most of the native soils in the area of the quarry have formed in the stony, gravelly, and <br />loamy colluvium material derived from the local igneous and metamorphic rocks. Soils <br />are typically shallow, < 10 foot thick, and support a number of different types of grasses, <br />Forbes, and evergreens in the higher elevations. Permeability of the soils is generally <br />moderate. <br />On the left side of the entrance road on the quarry property is an approximately 20 foot <br />high, vegetated embankment that is showing some movement by way of tension cracks <br />in the pavement at the top of the slope (Figure 2), and slumping in the surficial soils <br />(Figure 3). Average angle of the soil slope face is 36 degrees. Underlying the disturbed <br />soils is crushed quarry product consisting of 1/4 to 1/2 inch graded gravel. The surface <br />was then restored with approximately 2 feet of native soil composed of silt, sand, and <br />sandy silt with organic material. The soil was then revegetated. This potential soil slope <br />appears to be a sheet type failure, primarily in the vegetative layer, and is less than 2 feet <br />thick. It would appear that the heavy spring rains have caused the problem to develop. <br />Stock piles of gravel-size to cobble-size, crushed product can be seen on Bench 1 and <br />covering part of Bench 3. Between the benches are stable soil slopes made up of <br />colluvium with some alluvium and quarry product consisting of silt to cobble-size material <br />with enough fines to maintain the moisture content. This soil permits a healthy growth <br />of vegetation; at least with the high moisture available this season. <br />Rock Slopes - <br />The quarry consists of six flat rock benches with a steep rock back walls (Figure 4). The <br />first bench is defined as the bench in which the base of the East and West walls are <br />found. <br />3 <br />