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<br />3 <br /> <br />based on the Standard Penetration resistance (N-value, “blows per foot”) and groundwater <br />observations. <br />The strata changes were inferred from the changes in the samples and auger cuttings. The <br />depths shown as changes between strata are only approximate. The changes are likely <br />transitions, variations can occur beyond the location of the borings. <br /> <br />Piezometers Three (3) piezometers were installed in selected borings to further monitor <br />groundwater levels. The piezometers were installed in borings SB-1, SB-2 and SB-5. The <br />piezometers consisted of a 1-inch diameter slotted schedule 40 PVC well screen with a treaded <br />Schedule 40 PVC riser pipe. The bottom of the piezometer at boring SB-1 was set at about 57 <br />feet below the ground surface. The piezometers at borings SB-2 and SB-5 were set at about 24 <br />and 25 feet, respectively below the ground surface. <br /> <br /> <br />3.0 RESULTS <br /> <br />3.1 Soil Conditions <br /> <br />At the surface, the soil borings encountered about 1 to 4 ½ feet of topsoil that consisted of silty <br />sand or silty clayey sand that was dark brown or black in color and contained traces of roots. <br /> <br />Below the topsoil, the soil borings encountered sandy native alluvial soils that extended to the <br />termination depths of the borings. The sandy native soils consisted of; poorly graded sand, <br />poorly graded sand with silt and silty sand that were brown in color. <br /> <br />Penetration resistance values (N-Values), shown as blows per foot (bpf) on the boring logs, <br />within the sands ranged from 3 to 89 bpf indicating a very loose to very dense relative density. <br />However, most of the values within about 20 feet of the ground surface ranged from 3 to 20 <br />bpf indicating a very loose to medium dene relative density. <br /> <br />3.2 Groundwater <br /> <br />Groundwater was encountered in 5 of the soil borings while drilling and sampling at depths <br />ranging from about 12 ½ to 55 feet below the ground surface corresponding to elevations of <br />about 844 to 870 feet above mean sea level. The observed water levels are summarized in Table <br />1. <br /> <br />Table 1. Summary of Groundwater Levels <br />Boring Number Measured Ground <br />Surface Elevation <br />Approximate Depth <br />to Groundwater <br />(feet)* <br />Approximate <br />Groundwater <br />Elevation (feet)* <br />SB-1/P-1 898.9 55 844 <br />SB-2/P-2 881.6 20 861 ½ <br />SB-3 893.1 NE - <br />SB-4 890.4 NE - <br />SB-5/P-5 893.4 25 868 ½ <br />SB-6 882.4 12 ½ 870 <br />SB-7 880.0 NE - <br />SB-8 885.1 30 855