Laserfiche WebLink
i <br /> I <br /> Site Background Information Vanco Truck & Auto Plaza <br /> Page 4 of 6 <br /> Vadose/First Water Zone-This zone extends from surface grade to approximately 20 feet bsg Static <br /> water is at 20 feet bsg in the monitoring wells, however, the first saturated soil samples were <br /> collected at 30 feet bsg This indicates that the water table is confined by the overlying fine-grained <br /> materials This zone is characterized by moderate pore pressures <br /> Hydrogeologic Unit 1 (HU1) - Extending from 20 feet to approximately 30 feet bsg, HU1 is <br /> comprised predominantly of sandy silt, clayey silt, and silt Dominant hydraulic conductivities, <br /> based on CPT soil behavior types(SBTs), range between 1 x 10'and 1 x 10'B centimeters per second <br /> (cm/s) for silty to clayey type soils This interval is characterized by generally moderate pore <br /> pressures <br /> Hydrogeologic Unit 2 (HU2) - At the top of the current saturated zone, HU2 extends from 30 feet <br /> to approximately 38 feet bsg and is composed of silty sand to sand type soils Hydraulic <br /> conductivities for HU2 typically vary between 1 X 10 2 and 1 x 10' cm/s HU2 is characterized by <br /> generally lower pore pressures and is classified as a flow unit <br /> Hydrogeologic Unit 3 (HU3) - HU3 extends from 38 feet to approximately 45 feet bsg and is <br /> composed primarily of stiff, fine-grained soils, clayey silts, silts, and silty clays Hydraulic <br /> conductivities for these soil types generally range between 1 X 10-4 and 1 x 10 s cm/s for clays, silts, <br /> and stiff, fine-grained soils HU3 is characterized by varying pore pressures ranging between <br /> moderate and high and is identified as a confining layer <br /> Hydrogeologic Unit 4 (HU4) - HU4 extends from 45 feet bsg to approximately 50 feet bsg and is <br /> composed of silty sand to sand type soils Hydraulic conductivities for HU4 generally range between <br /> 1 x 10 z and 1 x i 0 5 cm/s HU4 is characterized by generally lower pore pressures and is classified as <br /> a flow unit <br /> Hydrogeologic Unit 5 (HU5) - Extending from 50 feet to approximately 70 feet bsg, HU5 is <br /> composed predominantly of stiff, fine-grained clayey silts, silty clays,and clay A thin silty sand to <br /> sand type soil is encountered at approximately 58 to 62 feet bsg and has characteristically low <br /> hydraulic conductivity Hydraulic conductivity generally ranges between 1 x 10 s and 1 x 10' cm/s <br /> for clays, silts,and stiff,fine-grained soils HU5 is characterized by varying pore pressures varying <br /> from moderate to very high, and is identified as a confining layer <br /> Hydrogeologic Unit 6 (HU6) - HU6 extends from 70 feet to 82 feet bsg and is composed of silty <br /> sand to sand type soils Hydraulic conductivities for HU6 generally range between 1 x 10'and 5 0 <br /> cm/s HU6 is characterized by very low pore pressures, and is classified as a flow unit <br /> Hydrogeologic Unit 7 (HU7) - Extending from 82 feet to total depth of the boring (100 feet bsg), <br /> HU7 is composed primarily of stiff,fine-grained clayey silts,silty clays,and clay A thin,cemented <br /> sand is encountered at approximately 94 feet to 95 feet bsg Hydraulic conductivity generally ranges <br /> between I x 10 5 and I x 1015 cm/s for clays, silts, and stiff, fine-grained soils HU7 is characterized <br /> Advanced CeoEnvironmental,Inc <br />