2002-06-03_REVISION - M2001107 - Laserfiche WebLink

Home Browse Search

GENERAL NOTES DRILLING & SAMPLING SYMBOLS: SS: Split Spoon - 1-'/8" I.D., 2" O.D., unless othewise noted HS: Hollow Stem Auger ST: Thin-Walled Tube - 2" O.D., unless othewise noted PA: Power Auger RS: Ring Sampler - 2.42" I.D., 3" O.D., unless otherwise noted HA: Hand Auger DB: Diamond Bit Coring - 4", N, B RB: Rock Bit BS: Bulk Sample or Auger Sample W B: Wash Boring or Mud Rotary The number of blows required to advance a standard 2-inch O.D. split-spoon sampler (SS) the last 12 inches of the total 18-inch peneVation with a 140-pound hammer falling 30 inches is considered the "Standard Penetration" or "N-value". For 3" O.D. ring samplers (RS) the penetration value is reported as the number of blows required to advance the sampler 12 inches using a 140- pound hammer falling 30 inches, repoded as "blows per foot," and is not considered equivalent to the "Standard Penetration" or "N-value". WATER LEVEL MEASUREMENT SYMBOLS: WL: Water Level WS: While Sampling WCI: Wet Cave in WD: While Drilling DCI: Dry Cave in BCR: Before Casing Removal AB: After Boring ACR: After Casing Removal Water levels indicated on the boring logs are the levels measured in the bodngs at the times indicated. Groundwater levels at other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater levels may not be possible with only short-term observations. DESCRIPTIVE SOIL CLASSIFICATION: Soil classification is based on the Unified Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency. FINE-GRAINED SOILS COARSE-GRAINED SOILS BEDROCK )~ SS fRS) js~s Relative Lsj 1~ Blows/Ft. Blows/Ft. Consistency Blows/Ft. Blows/Ft. Density Blows/Ft. Blows/Ft. Consistency < 3 < 2 Very Soft 0-6 < 3 Very Loose < 30 < 20 Weathered 3-4 2-3 Soft 7-18 4-9 Loose 30-49 20-29 Firm 5-9 4-6 Medium Stiff 19-58 10-29 Medium Dense 50-89 30-49 Medium Hard 10-18 7-12 Stiff 59-98 30-49 Dense 90-119 50-79 Hard 19-42 13-26 Very Stiff > 98 > 49 Very Dense > 119 > 79 Very Hard > 42 > 26 Hard RELATIVE PROPORTIONS OF SAND AND GRAIN SIZE TERMINOLOGY GRAVEL Descriptive Terms of Percent of Major Component Other Constituents Drv Weioht of Sample Particle Size Trace < 15 Boulders Over 12 in. (300mm) With 15 - 29 Cobbles 12 in. to 3 in. (300mm to 75 mm) Modifier > 30 Gravel 3 in. to #4 sieve (75mm to 4.75 mm) Sand #4 [o #200 sieve (4.75mm to 0.075mm) Silt or Clay Passing #200 Sieve (0.075mm) RELATIVE PROPORTIONS OF FINES PLASTICITY DESCRIPTION Descriptive Terms of Percent of Other Constituents Drv Weioht Term Plasticity Index Trace < 5 Non-plastic 0 With 5-12 Low 1-10 Modifiers > 12 Medium 11-30 High 30+ 1 ~~rr~con