8407 BROADWAY SECURE SPACE STORAGE Geotech Report 2025-04-24

EXPLANATION OF EXPLORATION LOGS SOIL DESCRIPTION: Soil descriptions presented on the borings logs are based on visual observations. Soil descriptions include density (coarse- grained soils) or consistency (fine-grained soils), moisture, color, major soil type, and grain size modifiers and should not be interpreted to suggest laboratory or field testing unless indicated on the logs. Soil descriptions include the following: Density/consistency, moisture, color, grain size modifier (adjective implying 31-49 percent), major soil type (CAPITALIZED implying 50+ percent), minor grain size modifier(some implying 6-12 percent, with implying 13-30 percent, and trace implying 0-5 percent), descriptive modifiers (i.e. roots, fill debris, cemented, etc.), and interpreted general geologic description. Descriptions may also include comments describing geologic properties such as dilatancy,toughness,structure,plasticity,and angularity of coarse-grained particles. Additional information regarding geologic properties is presented in the report text as applicable. DENSITY/CONSISTENCY: Soil density/consistency in borings is related to the blow count number in blows per foot using the sampling method 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 augmented by field Torvane or Pocket Penetrometer testing. Coarse-Grained Soils Density SPT Modified CA California Relative Descriptor (#blows/ft) Sampler Sampler Density Field Test (#blows/ft) (#blows/ft) (%) Very Loose I 0—4 0—4 0—5 I 0—15 Easily penetrated with%-inch steel rod pushed by hand. Loose I 5—10 1 5—12 • 6—15 I 15—35 Difficult to penetrate with'%-inch steel rod pushed by hand. Medium I Easily penetrated a foot with%-inch steel rod driven with 5-lb 11 —30 i 13-35 16-40 I 35-65 Dense hammer. Dense 31 —50 36—60 41 —70 65—85 Difficult to penetrate a foot with'%-inch steel rod driven with 5-lb hammer. Very Dense ! >50 1 >60 >70 I 85—100 I Penetrated only a few inches with%-inch steel rod driven with 5-lb hammer. Fine-Grained Soils Torvane Pocket Penetrometer Consistency SPT Undrained Unconfined Field Test Descriptor (#blows/ft) shear Compressive strength(tsf) Strength (tsf) Very Soft l 0—2 <0.125 <0.25 I Easily penetrates several inches by thumb. Soft 3—4 1 0.125—0.25 0.25—0.5 1 Easily penetrates one inch by thumb. ........................................... Medium Stiff 1 5—8 1 0.25—0.5 0.5—1.0 ; Penetrated over'%inch by thumb with moderate effort. Stiff 9—15 I 0.5—1.0 1.0—2.0 I Indented by thumb but penetrated only with great effort. Very Stiff I 16—30 1 1.0—2.0 2.0—4.0I Readily indented by thumbnail. Hard >30 >2.0 >4.0 Indented by thumbnail with difficult effort. MOISTURE Descriptor I Field Test Dry ' Absence of moisture,dusty,dry to the touch. Damp I Too low to achieve compaction Moist I Appears near optimum moisture content for compaction Wet I Too wet to achieve compaction Saturated 1 Below the groundwater table,visible free moisture. 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, 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. GRAIN SIZE Descriptor Sieve Size Grain Size 1 Boulder I >12" >12" Cobble 3—12" 3—12" Gravel 3"—#4 3"—0.19" Sand 1 >#4—#200 I• <0.19"—>0.0029" Silt/Clay Passing#200 I <0.0029" GRAIN SIZE MODIFIERS Descriptor Approximate Percentage Trace 0—5 Some 6—12 With.....................................................................r.................................................................................................................................................................... 13-30 Adjective(silty,clayey,sandy,gravelly).......f..................................................................._3.1..._..50_....................................................................