11-17-2025 - Agenda Packet Planning Commission - Full Packet

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UNIFIED SOIL CLASSIFICATION SYSTEM ASTM Designations: D 2487, D2488 Soil Classification Criteria for Assigning Group Symbols and Group Names Using Laboratory TestsA Group Group Name Symbol Coarse -Grained Gravels More Clean Gravels Cu>4 and 1<Cc<3 GW Well graded grave Soils More than 50% coarse Less than 5% than 50% fraction retained finesc Cu<4 and/or I>Cc>3E GP Poorly graded gra retained on on No. 4 sieve No. 200 sieve Gravels with Fines classify as ML or MH GM Silty gravel Fines more than 12% fines c Fines classify as CL or CH GC Clayey gravel ' Sands 50% or Clean Sands Cu>6 and 1<Cc<3 SW Well -graded sand more of coarse Less than 5% fraction passes finesD Cu<6 and/or I>Cc>3E SP Poorly -graded san No. 4 sieve Sands with Fines classify as ML or MH SM Silty sand ' Fines more than 12% fines D Fines classify as CL or CH SC Clayey sand Fine -Grained Silts and Clays inorganic PI>7 and plots on or above CL Lean cla Soils 50% or Liquid limit less "A" line more passes than 50 PI<4 or plots below ML Silt the No. 200 "A" line' sieve organic Liquid limit —oven dried 10.75 OL Organic clay (see Plasticity Liquid limit — not dried Organic SiltK.L.M.O Chart below) Silts and Clays inorganic PI plots on or above "A" line CH Fat clayK.L.N4 Liquid limit 50 or more PI plots below "A" line MH Elastic silt orgmin; Liquid limit —oven dried <0.75 Uri UrgaDlc clay Liquid limit — not dried Organic siltK.L.M.Q Highly organic Primarily organic matter, dark PT Peat Soil in color, and organic in odor SIEVE ANALYSIS �sc Opening(in.)+—&—Numta� 3 2.1'14 1 Y. % 4 10 M 40 60 W M0 0 z w a 60 50 a 0 40 z U 3o 20 10 4 Far dassifiration of finearained soils and finearained fraction of —."rained adla. Equation of "a' -line Horiwnt at Pl=4 to LL=25.5. then PI = 0.73 (ILL-20) ,�j; Equation of "U"-Tina ` Vertical a[LL=16to PI=7. rr . then PI = 0.9 (LL-B) V r • J C\' MH OR OH ML OR OL AMERICAN ENGINEERING TESTING, INC. Notes ABased on the material passing the 3-in (75-mm) sieve. BIf field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group name. cGravels with 5 to 12% fines require dual symbols: GW-GM well -graded gravel with silt GW-GC well -graded gravel with clay GP -GM poorly graded gravel with silt GP -GC poorly graded gravel with clay DSands with 5 to 12% fines require dual symbols: SW-SM well -graded sand with silt SW -SC well -graded sand with clay SP-SM poorly graded sand with silt SP-SC poorly graded sand with clay (D3o)2 ECU = D6o /Dlo, Cc = D)ox D6o FIf soil contains >15% sand, add "with sand" to group name. GIf fines classify as CL-ML, use dual symbol GC -GM, or SC-SM. If fines are organic, add "with organic fines" to group name. 'If soil contains >15% gravel, add "with gravel" to group name. 'If Atterberg limits plot is hatched area, soil is a CL-ML silty clay. KIf soil contains 15 to 29% plus No. 200 add "with sand" or "with gravel", whichever is predominant. LIf soil contains >30% plus No. 200, predominantly sand, add "sandy" to group name. MIf soil contains >30% plus No. 200, predominantly gravel, add "gravelly" to group name. NP1>4 and plots on or above "A" line. oPl<4 or plots below "A" line. PPl plots on or above "A" line. QP1 plots below "A" line. RFiber Content description shown below. g m ,00 o s 1'.a p.a oil 00 10 16 20 30 40 50 60 70 BO 90 100 110 PARTICLE SIZE IN MILLIMETERS LIQUIDLIMIT(LL) a'FO7s 15 `20° C' �-o.os.15-56 Plasticity Chart ADDITIONAL TERMINOLOGY NOTES USED BY AET FOR SOIL IDENTIFICATION AND DESCRIPTION Grain Size Gravel Percentages Consistency of Plastic Soils Relative Density of Non -Plastic Soils Term N-Value, BPF Term N-Value, BPF Term Particle Size Term Percent Boulders Over 12" A Little Gravel 3% - 14% Very Soft less than 2 Very Loose 0-4 Cobbles 3"to 12" With Gravel 15% - 29% Soft 2-4 Loose 5-10 Gravel #4 sieve to 3" Gravelly 30% - 50% Firm 5 - 8 Medium Dense 11 - 30 Sand #200 to #4 sieve Stiff 9 - 15 Dense 31 -50 Fines (silt & clay) Pass #200 sieve Very Stiff 16 - 30 Very Dense Greater than 50 Hard Greater than 30 Moisture/Frost Condition Layering Notes Peat Description Organic Description (if no lab tests) (MC Column) D (Dry): Absence of moisture, dusty, dry to touch. Laminations: Layers less than M (Moist): Damp, although free water not /2' thick of Term visible. Soil may still have a high differing material water content (over "optimum"). or color. Fibric Peat: W (Wet/ Free water visible, intended to Hemic Peat: Waterbearing): describe non -plastic soils. Lenses: Pockets or layers Sapric Peat: Waterbearing usually relates to greater than''/2' sands and sand with silt. thick of differing F (Frozen): Soil frozen material or color. Fiber Content (Visual Estimate) Soils are described as organic, if soil is not peat and is judged to have sufficient organic fines content to influence the Liquid Limit properties. Slightly organic used for borderline cases. Root Inclusions Greater than 67% With roots: Judged to have sufficient quantity 33 6a of roots to influence the soil Less than 33% properties. Trace roots: Small roots present, but not judged to be in sufficient quantity to significantly affect soil properties. 01CLS021 (07/08) AMERICAN ENGINEERING TESTING, INC. 129