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EXPLANATION OF EXPLORATION LOGS <br /> SOIL DESCRIPTION: Soil descriptions presented on the borings logs are based on visual observations. Soil descriptions include density (coarse- <br /> grained soils) or consistency (fine-grained soils), moisture, color, major soil type, and grain size modifiers and should not be interpreted to suggest <br /> laboratory or field testing unless indicated on the logs. Soil descriptions include the following: Density/consistency, moisture, color,grain size modifier <br /> (adjective implying 31-49 percent), major soil type (CAPITALIZED implying 50+ percent), minor grain size modifier(some implying 6-12 percent, with <br /> implying 13-30 percent, and trace implying 0-5 percent), descriptive modifiers (i.e. roots, fill debris, cemented, etc.), and interpreted general geologic <br /> description. Descriptions may also include comments describing geologic properties such as dilatancy,toughness,structure,plasticity,and angularity of <br /> coarse-grained particles. Additional information regarding geologic properties is presented in the report text as applicable. <br /> DENSITY/CONSISTENCY: Soil density/consistency in borings is related to the blow count number in blows per foot using the sampling method <br /> indicated on the logs.Soil density/consistency in test pits is related to a"Field Test"as described below. Soil consistency in test pits or borings may be <br /> augmented by field Torvane or Pocket Penetrometer testing. <br /> Coarse-Grained Soils <br /> Density SPT Modified CA California Relative <br /> Descriptor (#blows/ft) Sampler Sampler Density Field Test <br /> (#blows/ft) (#blows/ft) <br /> Very Loose 0-4 0-4 0-5 0—15 Easily penetrated with'/2-inch steel rod pushed by hand. <br /> ...................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... <br /> Loose 5—10 5—12 6—15 15—35 Difficult to penetrate with 1/2-inch steel rod pushed by hand. <br /> ...................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... <br /> Medium 11 —30 13—35 16—40 35—65 Easily penetrated a foot with%-inch steel rod driven with 5-lb <br /> Dense hammer. <br /> ...................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... <br /> Dense 31 —50 36—60 41 —70 65—85 Difficult to penetrate a foot with'Y inch steel rod driven with 5-lb <br /> hammer. <br /> .................................................................................................................. <br /> ................................................................................................................................. <br /> ..............................................,......................................................................................................................................................................................................................................................................... <br /> Very Dense >50 >60 >70 85—100 i Penetrated only a few inches with 1/2-inch steel rod driven with 5-lb <br /> hammer. <br /> Fine-Grained Soils <br /> Torvane Pocket <br /> Penetrometer <br /> Consistency SPT Undrained Unconfined Field Test <br /> Descriptor (#blows/ft) shear Compressive <br /> strength(tsf) Strength (tsf) <br /> Very Soft 0-2 <0.125 <0.25 Easily penetrates several inches by thumb. <br /> ......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... <br /> Soft 3-4 0.125—0.25 0.25—0.5 Easily penetrates one inch by thumb. <br /> .............................................................................................................................:................................................................:.........................................................................; .................. ................................................................................ <br /> Medium Stiff 5-8 0.25—0.5 0.5—1.0 Penetrated over inch by thumb with moderate effort. <br /> Stiff..........................................9..—..1..5................................0.5..—..1...0.....................................1..0...—.2.0.................... Indented...b...thumb but penetrated only with great effort.............................................................................. <br /> Y p Y 9 <br /> Very Stiff 16—30 1.0—2.0 2.0—4.0 Readily indented by thumbnail. <br /> ....................................................................:.......................................................,.........................................................................................................................................:............................................... .... .. ............................................................................................................................................... ............................................................................................ <br /> Hard >30 >2.0 >4.0 Indented by thumbnail with difficult effort. <br /> MOISTURE <br /> Descriptor Field Test <br /> Dry Absence of moisture,dusty,dry to the touch. <br /> ..................................................................................................................................................................................................................................................:.................................................................................................................................................................................................................................................. <br /> Damp Too low to achieve compaction <br /> ..................................................................................................................................................................................................................................................:.................................................................................................................................................................................................................................................. <br /> Moist Appears near optimum moisture content for compaction <br /> .................................................................................................................................................................................................................................................:.................................................................................................................................................................................................................................................. <br /> Wet Too wet to achieve compaction <br /> ..................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... <br /> Saturated Below the groundwater table,visible free moisture. <br /> MAJOR SOIL TYPE: Coarse-grained soils with over 50%of the material retained on the U.S.No.200 sieve. Coarse-grained soils include boulders, <br /> cobbles,gravels and sands. Fine-grained soils with over 50%of the material passing the U.S.No.200 sieve. Fine-grained soils include silts and clays. <br /> GRAIN SIZE <br /> Descriptor Sieve Size Grain Size <br /> Boulder >12" >12" <br /> .................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... <br /> Cobble 3—12" 3—12" <br /> ...............................................................................................................................................................i....................................................................................................................................................................s............................................................................................................................................................... <br /> Gravel 3"—#4 3"—0.19" <br /> ......................................................... ........................................................................:............................................................... .............................................................:............................................................................................................................................................... <br /> Sand >#4—#200 <0.19"—>0.0029" <br /> ......................................................... ............................................................................................................................. .....................................................................................:...............................................................c........................................................................................... <br /> Silt/Clay Passing#200 0.0029" <br /> GRAIN SIZE MODIFIERS <br /> Descriptor Approximate Percentage <br /> Trace 0—5 <br /> ...............................................................................................................................................................:......................................................................... ............................................................ <br /> Some 6—12 <br /> ...............................................................................................................................................................:............................................................................. .............................................................. <br /> With 13—30 <br /> .................................................................................................................................................................................................................................................................................................................. <br /> Adjective(silty,clayey,sandy,gravelly) 31 -50 <br />