1310 SE EVERETT MALL WAY Geotech Report 2022-10-25

� �.�: GENERAL NOTES SAMPLE IDENTIFICATION The Unified Soil Classification System (USCS), AASHTO 1988 and ASTM designations D2487 and D-2488 are used to identify the encountered materials unless otherwise noted. Coarse-grained soils are defined as having more than 50°/o of their dry weight retained on a#200 sieve (0.075mm); they are described as: boulders, cobbles, gravel or sand. Fine-grained soils have less than 50% of their dry weight retained on a#200 sieve; they are defined as silts or clay depending on their Atterberg Limit attributes. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. DRILLING AND SAMPLING SYMBOLS SFA: Solid Flight Auger-typically 4" diameter flights, SS: Split-Spoon - 1 3/8" I.D., 2" O.D., except where except where noted. noted. HSA: Hollow Stem Auger-typically 3'/d' or 4'/4 I.D. ST: Shelby Tube- 3" O.D., except where noted. openings, except where noted. BS: Bulk Sample M.R.: Mud Rotary - Uses a rotary head with Bentonite PM: Pressuremeter or Polymer Slurry CPT-U: Cone Penetrometer Testing with Pore-Pressure R.C.: Diamond Bit Core Sampler Readings H.A.: Hand Auger P.A.: Power Auger- Handheld motorized auger SOIL PROPERTY SYMBOLS N: Standard "N" penetration: Blows per foot of a 140 pound hammer falling 30 inches on a 2-inch O.D. Split-Spoon. N60: A"N" penetration value corrected to an equivalent 60% hammer energy transfer efficiency (ETR) Qu: Unconfined compressive strength, TSF QP: Pocket penetrometer value, unconfined compressive strength, TSF w%: Moisture/water content, % LL: Liquid Limit, % PL: Plastic Limit, % PI: Plasticity Index = (LL-PL),% DD: Dry unit weight, pcf s,sz,� Apparent groundwater level at time noted RELATIVE DENSITY OF COARSE-GRAINED SOILS ANGULARITY OF COARSE-GRAINED PARTICLES Relative Densitv N - Blows/foot Description Criteria Angular: Particles have sharp edges and relatively plane Very Loose 0-4 sides with unpolished surfaces Loose 4- 10 Subangular: Particles are similar to angular description, but have Medium Dense 10-30 rounded edges Dense 30-50 Subrounded: Particles have nearly plane sides, but have Very Dense 50-80 Extremely Dense g0+ well-rounded corners and edges Rounded: Particles have smoothly curved sides and no edges GRAIN-SIZE TERMINOLOGY PARTICLE SHAPE Component Size Ranqe Description Criteria Boulders: Over 300 mm (>12 in.) Flat: Particles with width/thickness ratio>3 Cobbles: 75 mm to 300 mm (3 in.to 12 in.) Elongated: Particles with length/width ratio > 3 Coarse-Grained Gravel: 19 mm to 75 mm (3/4 in.to 3 in.) Flat& Elongated: Particles meet criteria for both flat and Fine-Grained Gravel: 4.75 mm to 19 mm (No.4 to 3/<in.) elongated Coarse-Grained Sand: 2 mm to 4.75 mm (No.10 to No.4) Medium-Grained Sand: 0.42 mm to 2 mm (No.40 to No.10) RELATIVE PROPORTIONS OF FINES Fine-Grained Sand: 0.075 mm to 0.42 mm (No. 200 to No.40) Descriptive Term% Drv Weiqht Silt: 0.005 mm to 0.075 mm Trace: < 5% Clay: <0.005 mm With: 5%to 12% Modifier: >12% Page 1 of 2