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Home My WebLink AboutCT 79-25; HIDDEN MEADOWS NORTH DEVELOPMENT; ROPERT OF GEOTECHNICALINVESTIGATION; 1981-07-13-I. REPORT OF GEOTECHNICAL INVESTIGATION PROPOSED HIDDEN MEADOWS NORTH DEVELOPMENT LA COSTA AREA, CARLSBAD, CALIFORNIA PREPARED FOR: DAON CORPORATION 1241 Elm Street Carlsbad, California 92008 PREPARED BY: SHEPARDSON ENGINEERING ASSOCIATES, INC. 1083 North Cuyamaca Street E1 Cajon, California 92020 DATED: July 13, 1981 f3EDTECHNICAL ENf3INEERS Daon Corporation 1241 Elm Street 'Carlsbad, California 92008 ATTENTION: Mr. J. Goff Project Manager • '.:'. - SHEPARDSON ENGINEERING ASSOCIATES INC. 10S3 N. CUVAMACA STREET EL CAJON. CA. saoao TELE 44S·SS30 July 13, 1981 s. E.A. 110244 SUBJECT: Report of Geotechnical Investigation, Proposed l-lidden Meadows North Subdivision, Alga Road and Melrose Avenue, La Costa Area, Carlsbad, California. Gentlemen: In accordance with your -request, we have completed our geotechnical investigation of the area of the proposed Hidden Me~qows North Sub.,.. division. We are transmitting, herewith, a report of this investigation •. The analysis of our findings is intended to provide the required information to design the foundation and grading plans for .the proposed. subdivision. in general, we found the site to be; underlain preqominantly by expansive mudstones and siltstones of the 'Del Mar. Formation. Thes.e expansive soils wili require speciat grading or desig"h procedures C to mitigate the potential damage due to their shrink-swell characteristies. . A relatively small. quantity of potentially compreSSible .alluvium was encountered in the existing drainage which flows southeasterly through· ·the site; This alluvium will require removal and recompaction during the site grading. In our opinion, the site is suitable provided the recommendations contained followed. for the proposed development, in the body of this·' report are If you have any questions after reviewing our report, please do not hesitate to contact this office. ,e . July 13, '1981 -2-S. E.A. 110244 This opportunity to be of service is sincerely appreciated. DES: KLS:.jgr cc: (4) Submitted Respectfully submitted" ) . . SHEPARDSON ENGINERRING ASSOCIATES, INC. ~.~~ ~hepard ,R.C.E President ' Ken<lall L. Sherrod, C.E.G.· Vice President (4) Rick Engineering (Carlsbad) (4) Westec Services ,.:; '4' "J ,I TABLE OF CONTENTS PROJECT DESCRIPTION & SCOPE FINDINGS Site Description . Site Geology. RECOMMENDAT IONS Site Preparation. Transition Lots Earthwork. Foundations . Alternate I Alternate II Foundation Condition A. Foundation Condition B • Foundation Condition C. Foundation Condition D. Slope Stability Canyon Sub drain Settlemen t Characteristics Structural Sections . Earth Retaining Structures • Allowable Passive Rressure Active Soil Pressure FIELD EXPLORATIONS LABORATORY TESTING . . . • , . . , I Page 'No. 1 2 2 2 :3 3 4 4 4 4 5 5 7 - .. 8 10 '11 12 12 12 13 . 13, 13 13 . ,14 July l3, )981 -3-S. E.A. 110244 Quaternary alluvium is limited to the vicinity of the southeasterly trending drainage on site. The surface area of this alluvium covers approximately 8 to 10 percent of the site. Our test borings indicate these ma~erials range in depth from, approximately 5.5 feet to 7' feet. This alluvium is primarily the result of siltation. behind a small, earthen dam located near the south-central boundary. Groundw~ter was encountered in our test boring Nos. 6 and 7 within the alluvial' materials. This water appears to be perched within the alluvium on top of the Del Mar Formation. Although landslides are common to the Del Mar Formation, dow:n.hole' logging of large diameter test borings in suspected landslide areas within this site indicate' that the underlying materials do hot show evidence of being landslide involved. In our opinion, there a,re no e~isting landslides within the project. If. appears that essentially all of the materials 'which w'ill 1:?¢ encourtte.red during grading of this project win be detrimentally expansive. Special engineering, deSigns are presented in this report which are intended _to mitigate the potential damage from these expans~ve soils. rhere are no known faults or other geologic hazards within,. the immediate vicinity of the project. RECOMMENDA T IONS Site Preparation General: Due to the compressible nature of the r existing alluvial material and the fill materials composing the existing earthen dam, we recommend. that they be removed to firm natural ground and be repla;ced as uniformly compacted fill. Firm natural ground is defined as soils which. . ..:.-,--.... ~ ,", I .. I • ::'~i.;' \ .... _ "_..:. ...... _._ •• --":"'_"; -=--.:_-___ . July 13, 1981 -4- possess an in situ density equal to or greater than 85% of its" maximum. dry density. We estimate the depth of removal an<;l" recompaction in these "areas will average 7 feet. Tra~sition Lots: Foundations supported partially on cut and partially on fill are not recommended. The tendency of cut and 'fill sons· to compress differently will probably result in unequal structural support and consequential cracking. Therefore, in transition areas, we recommend that the entire area be undercut" and be replaced with soils compacted to a minimum of 90%. The undercutting should be carried to a depth' of two foot below the base of the deepest footing. Earthwork: All earthwork' and grading cont~mplated for site preparation should be accomplished" in accordance with the attached Recommended Grading Specifications and Special Provisions. Utility trench backfill within 5 feet" of the proposed structure and beneath asphalt pavement should be compacted to a minimum of 90%. The maximum dry density" of each soil. type should be determined in accordance with A.S. T. M. Test Method 1557-70T, Method A or C. Foundations General: Due the expansive characteristics of tn.e prevailing foundation soils described above, we recommend that one of the two alternatives presented below be utilized in the design -·of this project, . so that structural damage is not likely to occur due to expansion' .. Alternate I It is recommended that all building pads constructed within this project be provided with a minimum of 3.0 feet of non-expansive .material . immeo.iatelY below finish grade. This applies to both cut and fill lots. The lateral extent of this recommendation shall apply. to the area "from the street right-of-way to a line located not more than 15 feet from the ( ~ 'I' • ..;.>, .::-"...;..:;='-e~...;:'-=':'=~---'-~= .. =,,--~-.... -' .~.~.-;: . '. ; .. ~-: .--~ ...... _- July 13, 1981 -5-S. E.A. 110244 rear 'property line or level building pad area and for the' full width of the lot. The, expansive soils from 3.0' feet to 4.5 feet below finish grade must be scarified, watered to not less than 3% .above optimum moisture content and compacted to not less than 90% of maximum dry density prior to placing the non-expansive material. Conventional footings designed to meet the remol9.ed· soil $trEmgths of the imported materials would then be used for the structure. It is our opinion that there is insufficient non-expansive materials, within the boundaries of this project, to comply with this recommendation thru the utilization of on-site soils. Alterna te II This alternative provides for reinforced and strengthened foundations and slabs to combat the potentially damaging effects of the expansive soils within this project. We do not anticipate that foundation con-. ditions, where the native soils possess less than 3% expansion", will be. encountered within this project. Foundation Condition A All lots which receive this, foundation classification will pos,sess expan ..... sive soils which exhibit an expansi.on of not less ,than 3%, nor. more than. 8%, when tested from an air dried to saturated condition under a surcharge load of 150 psf. These soils will be examined' for a depth of not less· than 3 feet below finish grade. 1. All footings should be founded·a· minimum of· 18 inohes below adjacent finish grade and may be designed for an allowable s~il bearirig pressure of 2,100 psfo Footings should, have a minimum width or diameter of 12 inches. iJ ,_, I \ ~' 10 ,,':.-:"'=::'~,!:;"),.~'=';;::!".:.~ •• _~---=-..... _~-::.....=--;:;:::.::..~~--.-.. July i3, )981 -6-S. R.A. _ 110244 2. Both exterior and -interior continuous footings -should be reinforced with one #4 bar positioned 3 inches above the bottom of the footings an one #4 bar positioned one inch clear below finish 'floor or the cold joint between the foundation -and slab pour. Pi~r footings need not be reinforced. 3. Interior slabs should be a minimum of 4 inches in thickness and underlain by a 4 inch blanket of clean sand or crushed rock. Further, interior slabs should be reinforced with 6"x6"-10/10 welded wire mesh and completely surrounded with a continuous f~oting. 4. Exterior slabs should be a minimum of 4 inches in thickness and constructed on native soils prepare~ in accordance with the recom- mendations presented in item No. 6 shown below. Further, exter.ior slabs should be provided with weakened plane. joints as recommended hereinafter. 5. Weakened .plane joints for exterior slabs should be provided for -any slab greater than 5 feet in width. Any slab between 5 arid-10 feet should be provided with a ~ongitudinal weakened plane joint at its <;:enter line. S~~bs exceeding 10 feet in width should be ptovided with a weakened plane joint located 3 feet inside the -exterior perimeter, as indicated on -the attached Figure A. Both trq.nsverse and longitudinal weakened plane joints should be· constructed as detailed on Figure A. 6. Clayey soils should not be allowed to dry before plating concrete. - They should be sprinkled, if necessary, to-insure that the soils are kept in a very moist condition or.: at a -moisture content exc,eedirtg 2% above optimum moisture content.·- 7. Surface drainage should be directed away from the prop.osed foundation. ·1 July 13, 1981 -7-s. E.A. 110244 8. Prior to pouring concrete, the foundation excavations should bE! inspected by a representative of this office to insure that the above recommendations have been followed. Foundation Condition B All lots which receive this foundation condition classification will contain expansive soils which exhibit an expansion of not less than 8%, nor more than' 12%, when tested from an air dried to' saturated condition under a surcharge load of 150 psf. 1. All footings should be founded a minimum of 18 . inches below adjacent finish grade and may be designed for an allowable soil bearing pressure of 2,000 psf. Footings should have. a m,inimUm width or diameter of 12 inches. 2. Both exterior and interior continuous footings sho~ld be reinforced with two #4 bars positioned 3 inches above the bottom of the footings . and two #4 bars positioned one inch clear b~low: finish.' floor or below the cold joint below the foundation and slQ,b pour. Pier footings need not be reinforced, although exterior piers should . e.xtend not less than 3 feet below adjacent grade. . 3. Interior slabs should be a minimum of 4 inches in thickness and underlain by a 6 inch blanket of clean sahd or crushed' rock. Further, interior slabs should be reinforced, with 6"'x6"-10/10 welded wire mesh and completely surrounded with a continuous footing ~ 4. Exterior slabs should be. a minimum of 4 inches in thickness and constructed on native soils prepar:.ed· in a.ccordancewith the recQm~ mendations presented in item No. 6 shown below.· Further, exterior slabs' should be provided with weakened plane joints as recommend¢d hereinafter. Exterior slabs should be reinforced with 6"xB"-10/10 welded wire mesh. .t· fJ '1 ~-~-'="',,~ --=.=-=-'-=-== July 13, 1981 -8-S. E.A. 110244 5. Weakened plane joints for exterior slabs should be provided for any slab greater than 5 feet in width. Any slabs between 5 -and 10 feet should be provided with a longitudinal weakened plane joint at its center line. Slabs exceeding 10 feet i~ width shoul<.i _ be provi4ed with a weakened plane joint located 3 feet inside th~ exterior· perimeter, as indicated on the attached Figure A. Both transverse and longitudinal weakened plane joints should be constructed as detailed on Figure A. 6. Clayey soils should not be allowed to dry before placing concrete. They should be sprinkled, if necessary, to insure that the soils are kept in a very moist condition or at· a moisture content exceeding 2% above optimum moisture content. 7. Surface drainage should be directed away from the. proposed' foundation. 8. Prior to pouring concrete, the foundation excavations; -'should be inspected by a 'representative of this office to insure that the above recommendations have been followed. Foundation Condition C: All lots which receive this foundation. condition classification will contain expansive soils which exhibit an eXp.ansiQn of mor~ than 12% when tested from an air dried to saturated conditi0t:l under a surcharge load of 150 psf. These soils will be -examined for a· depth of 3 feet below finish grade. L All footings should be founded a.djacent finish grade and may be~ring pressure of 2,000 psf. width or diameter of 12 inches. a minimum or be designed for Footings should 24 inches' below an 'allowable soil have a miriimum 2. Both exterior and interior continuous footings should be reinforc.ed . . with. two #5 bars positioned 3 inches above the bottom of the footings and two . #5 bars positioned one ·~nch clear below fini-sh July, 13; )981 -9-S. E.A. 110244 floor or below the cold joint below the foundatiori and slab pour. Pier footings need not be reinforced, although exterior: piers should extend not less than 3 feet below adjacent grade. 3. , Interior slabs should be a minimum of 5 inches in thickness and underlain by a 6 inch blanket of cr~shed rock. Further, interior slabs should be reinforced with #3 bars placed 12 inches on center each way and completely surrounded with a continuous footing. 4. -Exterior slabs should be a minimum of 5 inche's in thickness and constructed on native soils prepared in accordance with the recom- mendations presented in item No. 6 shown below. Further" exterior slabs should be provided with w-eakened plane joints as recommended " hereinafter and reinforced with #3 bars placed 18 inches on center each way. 5. Weakened plane joints for exterior slabs should 'be provided for any, slab greater than 5 feet in width. Any slabs between 5 and 10' feet should be provided with a longitudinal weakened plarie 'joint' a,t its center line. Slabs exce,eding 10 feet, in width should" be provided,. with a weakeI?:ed plane joint located 3 feet inside the extedor' perimeter, as indicated on the attached Figure A. ,1;3oth transverse and longitudinal plane, joints should be constructed as detailed on' Figllre A. , 6. 'Clayey soils should nof be allowed to dry before :t;>lacing concrete. They should be sprinkled, if necessary, to insure 'that the soils are kept in a very moist condition or at a moisture content exceeding 2% above optimum moisture content., 7. Surface drainage should be directed away from' the proposed foundation. fJ q e ..} -"~ .. ,-~,"! .. =-==.,,, .. ' '_., ..... ~~==~--.~~~. '-,." .. -. .' .. -.. ,'~ '~~""=~~·~'-~=~-'=:··~"~·~~'''-i}''oi, ' ,I July 13; 1981 -10-s. E.A. U0244 8. Prior to pouring concrete, the foundation. excavations should be inspected by a representative of this office to insure that the above recommendations have been followed. Foundation Condition D (Alternative Design): An alternate pte-stressed concrete foundation and slab design for soil Conditions "B" & "C" may be u,tilized. This design should be pr'epared by a register~dcivil engineer experienced in the design of pre-stresses con,cretestructures. The preparation of the foundation soils and detailed recommendations regarding foundation construction and pre-stressing' requirements should be prepared in cooperation with your structural design consultant. Exterior slabs should be prepared as described in Foundation Condition "c" above. All lots which contain soils within 3 feet of finish grade tbat exhibit an expansion greater than 12% should be regJ;'aded to remove the critically expansive soils. In consideration of the P'?tential for lateral movement of foundations construCted parallel .. to, and within 10 feet of the· top of any .cut ,or fin slopes constructed from the Del Mar Formation soils, we recomth~nd that the following foundation design criteria be considered. 1. The depth of the foundation shall be sufficient to extend not less than 12, inches below a line parallel to and 5' feet' in from the fac-e .. of the slope. 2. All foundations within 10 feet" from the top Qf a slope shall contain 3. , not less than· the reinforcement re.commended in "FoundatJon Condition B" and be designed to support a maximum dead load of 1 ,000' psf. , All' foundations within 10 feet of the top of a slope, andpa,ra.t}eI to the slope, should be tied into' other foundations within the structure' .. -.. ' ~, . -.... ~-~-~ .~~.,.l';'~-.:.:-~:.....-~_ , i • . --._-.,-----,. --~.' , .. .:...~\,;; .. ,; .. ;:-=-:t'"_....::::.::....,;::~:-_~--:" .... ...,..--= __ . __ ._ ... " July 13, ,1981 -11-S. E.A. 110244 whiCh are at least 20 feet from the top of slope. These cross tie's should be constructed perpendicular to the top of slope, consist of at least 12"xI2" concrete bea'm reinforced with two #4 bars, and pe spaced at not greater than 15 foot intervals. The above recommendations are intended to supplement the requireIl!ents of Carlsbad Ordinance No. 8086, Section 11.06.110. Adjacent footings founded at different bearing levels should 1;>e so located that the slope from bearing level to bearing level is flatter than one unit horizontal to one unit vertical. The allowable soil bearing pressures described above' may be' increase'd by one-third for wind and/or seismic loading and should 'be. deGreased by 'one-fourth for dead loads only. Slope Stability Utilizing the results of laboratory· tests performed on representative samples of native on-site materials, our calculations inciicate tha,t 'cut and fill slopes con~tructed from on-site materials should be st~ble with. relation to deep-seated failures if constructed at <;>r flatter -than the following. recommended slope ratios 'expressed in horizontal to vertic~i units for the indica ted heights: . Cut Slopes to 40 feet in height: 2: 1 Fill Slopes to 40 feet in height: 2: 1 The above maximum heights incorporate' a factor of sa'fety of 1-.5 against deep seated failure. It has surficiai been our experience that there , slope failures in slopes above is a de·finite risk 6f shallow 15 feet in hei-~ht constructed I I . . . -t,~~~..:· . ..;..:..~=·.;.-:....;::::..::~---===-=...,~';.~ ..... ~·· ....:.-=-.::..:..--_. __ .-.t ... July 13, ,1981 -12-s. E.A. 110244 from relatively weak soils such as those present at this site. These failures are a direct result of water penetrating the outer few feet of soil on the slope face and ultimately re'sulting in supersatura,ted conditions which result in mudflow type of failures. We' have found that sub~urface slope drains appear to be effective in preventing such failures. We therefore recommend that .all slopes greater than 15 feet in . . height be constructed with a subsurface slope drain located at mid-slope neight. Details for these recommended slope drains 'are shown on the a ttached Figure B. Canyon Subdrain It has been our experience that there is a tendency, itl residential developments,' for water to build-up in fill areas and, move along old buried drainages. We there'fore recommend that -a canyon subdrctin 1;>e installed in the existing canyon trending southeasterly across the site. The recommended location of this subdrain is shown on the ~ttached Plate No. 1. Also, attached as Figur~ C is a cross-sectional detail of the recommended subdrain. Settlement Characteristics: The anticipated total and/ol;' differential settle- ments for, the proposed structures may be considered to be, within toierable limits, provided the recommendations presenteo. in this' report are followed. Structural Sections ,Although no specific soil samples were taken or -tested to, determiI1e structural sections, our experience with similar soils would indicate , that, for estimating purposes, the following structural sections maybe assumed: Major Streets (Estimated Traffix Index of 5.5) 3 Inches Asphalt Concrete Over 10 Inches Aggregate Base Class II -", ./ Jul~ 13, 1981 -13- Interior Streets 2 Inches Asphalt Concrete Over '1, 9 Inches Aggregate Base Class 11 Earth Retaining Structures Allowable Passive Pressure: The allowable passive pressure. for th.e prevailing soil condition is 150 psf. at the surfac~, increas~ng at a rate- of 90 psf per foot of depth. This passive pressure has been cortlput~d using a factor of safety of 3 and may be incr~ased by one-third for wind and/or seismic loading. The coefficient of friction of concrete to soil may be assumed to' be Q.26 for resistance to horizontal movement. Active Soil Pressure: Active soil pressures for the design of earth retaining structures may be assumed to be equivalent to the. pressure df a fluid weighing 55 pcf and 75 pcf for unr~strained and restrained retaining walls, respectively. These soil pressures are for no surcharge and for a' drained and level backfill condition. If the. backfill will not ! be level, or if a surcharge is anticipat~d, this office should be contacted for the necessary increase in soil press~re. FIELD EXPLORATIONS Seventeen subsurface explorations were made at the locations indicated on the. attached Plate No. 1 on December 10, 1980, June-10, 1981 and June 26, 1981. These explorations consisted of borings drilled: by m~ans , of a rotary auger drill rig, borings drilled by means of a rotary bucket type drill rig and trenches' dug by means of a backhoe. The explorations were conducted under the observation of -our ert'gineetin:g geology personnel. The explorations were carefully logged when made. These logs. are presented on the following Plate Nos. 2 thru 13. The soils are described· July 1"3, 1981 -14-S.,E.A. 110244 in accordance with, the Unified Soils Classification System, as illustrated on the attached simplified chart. In addition, a verbal textural description, the wet color, the appar:.ent moisture, and the density or consistency are given on the logs. Soil dens,ities for granula'r soils aTe given as either very loose, loose, medium dense, dense, or .-very dense. The consistency of silts, or clays is given as either very soft, soft,' medium stiff, stiff, very stiff, or ha:r;-d. Representative core samples were obtained by means of a split tube sampler driven into the soil be means of the "kelly bar" of the drill rig. The energy required to drive the split tube sampler is indicated on the boring logs as "blows per foot". The core samples were car~fully removed, sealed, and returned to the laboratory for testing. Disturbed and undisturbed samples of typical' and representative soils were also obtained from the backhoe trenches and returned to' the laboratory for testing. LABORATORY TESTiNG Laboratory' tests we:-e performed in accordanc~ with' generaliy atce:pted American Society for Testing and Materials (A~S.T'.M.) test methods .or suggested procedures. Representative samples were tested for their natural density and moisture coptent, moisture content, expansive potential, . ! cohesion intercept. The results of these 14 thru 16 and the boring logs. maximum angle of tests are density internal presented and opti.mum friction a;nd on Plate Nos • ,The expansive potential of clayey soils was determined in accordance: with ,the foHowing test procedure. Allow ·the trimmed, undisturbed or remolded sample to air dry to a . 0 constant moisture content, at a temperature of 100 F. Place the dried sample in the consolidometer and allow to compress' under 'q. load of 150 psf. Allow moisture to contact the sample and meas:ure its expansion from an air-dried to saturated condition. G..~1'~~y ~u.uY\UM 1"~1~ ~ ~, ft<1· / -----" ~W~\l..I wN1'N..-1' • ". ·11~'/.....t'<~\ .. ,J'7";' '~"' • .'''~ :6oA"\'~';41 .. f;.··"· : .• ", . •• ",~ ~1''Ii:.:~,.~," __ <,..~~1 ~ ""~ .... ":~'. ___ , ~ .~. ~ .-r~NlH t..()lA110N~ ~ , SEA.. \11Wt-N ··M~AOCNJ6······ SHEPARDSO~ ENGINEERING ASSOCIATES, Inc. ' .. ' ,l ., , ." - 8-- 10- - 14,' ..I B 16....1 U - 18-. - \ \ f\ 1\ f\ '1\ 1\ \' f\ 1\' \ , Light Brown to Brown, Moist to Wet, Medium Dense, Clayey Sand & Clay to Clay Gray and Orange, Moist to Wet, Medium Stiff, Horizontal Bedding, Minor Caliche (Del Mar) Siltstonl! f\ I ,......Lots of Gypsum -Thin, 6" Beds ,ML/ 1\ \~ CL r\ 1\ i\ \ +-Gypsum in sandier beds i\, \ ML/ l'\ B CL 1\ \ ,1\ , GraY,Streaked Orange, Moist, Stiff, Siltstone -Ciaystone Beds -Horizontal Bedding, some thin Laminae - , i 26...1 u \ \ Massive 1\ 1\ ~ 'Q9.'! /9.2. -r\ 28-1\ ~ I -, r\ 1\ '\ r\ 30~ U 1\ ~ r\ '32--\ \ r\ 34-- 36. U \ \ ,r\ ' Laminated Again KEY BLOW COUNt < K ::a 3" O.D. Sampler J Kelly bar of drill rig drop 1" per blow. L ::a 3" O.D. Sampler, 140lb. hammer, 30" drop S • Standa~d Penetrometer SAMPLE TYPE . U = Undisturbed Drive Sample C ::a Chunk Sample B = Bulk Sample .e.· sHEPARDSON ENGINEEJUNG .~~1ES. INC, TupnEN !'iEAD01ilS ,NO~TH .. KLS .1?/10/RO ' 110244 : PLATE NO'. 2 E-t root root~ root rs. ...:II-f '" ~H i5 c3 g,. Cl)O root ...:I Q 3.8 --~o_ - 42- - 44- - ~6 -- ~8 - - 50- - ------ -, -..,.. ------- ...:I I-f 0 CI) • CI) Q.CI) ~:l rs.u i (,!) BORING NO. 1 0 ...:I 455 ELEVATION: BORING U I-f --~ DESCRIPTION (,!) " 1\" +-'ibin Brown Interbed ." ~ 1\ i\ Some Free Water DIAl . ,,~ Many Thinly Laminated Beds -Shale 1\ +-Seepage "1\\ ! " \ [\' ~ ~ Massive with Fractures i\ " ~ ~ -" ~ CL ~ ~Dark Brown, Wet, Stiff, Clay \\1 ~- CLI '\ \ Gray Mottled Orange, Wet to saturate'd, Stiff, Clay & ML\ ~ Silt (Harder, some water along Fractures) 1\[\ END OF BORING m BLOW-COUNT , K = jlt O.D. Sampler, Kelly bar of drill rig arop l' per blow. L :It 3" O.D. Sampler, 140lb. hammer, 30n drop S • Standard Penetrometer SAI.'1PLE TYPE . U'" Undisturbed Drive Sample C ,.. Chunk Sample HIDDE~. HE.ADOWS-,,:;~ORTH.. _-. KLS . 12/10/80 l ".f B .. Bulk Sample 110244 PLATE NO.' 3 ~-----.------------------------------------~~~--~--~.~------~------~~----~--~ .'. • .!., ~ -, 8-- 10- Brown, Wet, Medium Stiff to Stiff, Clay with '. Cobble B. CL ~ .. I-ft...-I-------------------------t i\ CL) 1\ Light Gray and Orange, Wet, Medium Stiff to U ML"!\ Stiff, Siltstone -Claystone (weathered') B 1\ 1\" Bedding Dipping East to Southeast 250 , Soft \ Loose, Beds 1\ i\ -.I U 12_ .. \ " 1\'" Gypsum Crystals \ i\ , --~4 _ ~6 :i U - ~8 --~O ..... .J U,. ~2 ..;.. -~4 _ - ~6 _ --~~- -~O ~ - \ 1\ \ Alternating Orange Brown Gypsum rich' beds and Gray Siltstone (Like Boring NQ. 1) \ ... -Dip shallows to 50 East to Nor.theast (No Planes) 1\ \..,... Dip Swings to 50 Northwest . \ , \.-Some Non-Slide Thin Clay Beds \ ..... Orange Brown 3" Siltstone. Bed Dips 5,0 Northwest 1\ \ More Fissile Below -20', same beddin~: a·.t,titud~ ,\ \ \ , 1\ \ \ I" 1\ I\f\" f\ CL/I' 1\ Gray, Wet, Very Stiff to Hard, Siltf?tone -Clay~ ~2 _ , ML 1\ stone, Much Denser, Some Sl.liceou. s Zones ~I'~----~--------~--------~----------~~ ~ ~/~~ -~4- - 36-k~~ r ".\,.. Varigated Pink, Gray, Purple, Yellow to Gray & Orange, Moist to Saturated, Stiff to Dense, Clast~ of Granitics, Some Clayey Decomposed Granite: (some ,Free Water) KEY BLOW COUNT -< K = 3" 0.0. Sampler, Kelly bar of drill rig drop l' per blow. L .. 3" .. 0.0. Sampler; 140lb. hammer, 30" drop S ,.. Standa;-d Penetrometer SAHPLE TYPE . HIDDEN~.EADOWS· NORTH-'::-;_.-; • • • • oJ .. -_.. .,. .. , I I. U ::& Undisturbed Drive Sample C .. Chunk Sample KLS . 1 ~I 1 0 I~ O~ . B ::& Bulk Sample 11.0 244 .~-. PLATE NO~ 4 , ~~ ___ .~ __ ~. _______________________ L-. ___ ~, ____ ................... __________ __ ., Highly Weathered Palesoil Decomposed Granite - 40-Grades into Weathered Fractured Rock Below -40" - 4l- - 44- -END OF BORING 46- -:------..... --------------/ ---= ------- KEY BLOW COUNT -< ~E& K os 3" O.D. Sampler, Kelly bar of drill rig drop l' per blow. L = 3" 0.0. Sampler, 1401b. hammer, 30" drop S = Standafd Penetrometer SAMPLE TYPE U = Undisturbed Drive Sample C os Chunk Sample B '" Bulk Sample 5HEPMDS()N ENGINEEIUNG A$SOCIATES.INc. .' " tt1DDEN ME,ApOWS NORTH" KL,S 1~/10/8(j 110244 PLATE ~O. 5 ; ,- " ... - 2- -Bag 4 -'* 6- -- ...:. -,- - --.. '- .,... - -'-., -:- 2_ -, 4- - 6-I-- '-------- ----- '. , ~.~ Brown~ Moist, Loose, Clayey· Sand .~~J-----------------~""'--~-+ ~~ Dark Brown Green, Wet, Soft, Clayey Sa~d & Clay K~ ~:~~:' Rust Tan, Wet, Medium to Soft, Clayey Sand & Clay \.\·'x\ End of Boring Boring 4 Dark Brown to Drk Brown, Green, Mois,t to Wet" ~oose to Sof~_, ,. Clayey Sand & Clay End of Boring KEY -'-BLOW COUNT K = 3" O.D. Sampler, Kelly bar of drill rig drop. l' per blow. L = 3'·' O.D. Sampler" 140lb. hannner, 30" drop S = Standard Penetrometer SAMPLE TYPE . U = Undisturbed Drive Sample C =.Chunk Sample :B = Bulk S~mple SHEPARDSON E~NEEJiING ASsoCIATES. I~. HIDDEN. MEADOWS NORTIf ; CB 6/26/81 U0244 .! - 2- - 3 ~ag < ... - 4- - --- ---,- -' --_ .... - 2--: . ...:..' 4-' -6~, -f.- 8_ --- -- .. - ---- ,~~~;~ Dark Brown, Moist to Wet, Soft. Clayey Sand & Clay , ), "" "'\ ~'\~.~ !., • ~ , .' .' ~ ~ Tan Pale Gray, Moist, Medium to Soft,Clay End 'of Boring -"{ ~'j..:':;~ Medium to Dark Green, Wet to Saturated, Medium Soft tQ ~'( )'. ,1\\" Loose, Fine Clayey Sand ~ "-', -?' • '\ "C:~ ~ \ H . , .. ':; '~ '\ ":" , ,,':' ~ Tan to Rust, Wet, Medium to Loose, Clayey Sand End of Boring BLOW COUNT K = 3" O.D. Sampler, Kelly bar of drill rig drop 11 per blow. L = 3'~ O.D. Sampler, 1401b. hammer, 30" drop S = Standard Penetrometer 5HEP~DSON ENGINEEflING A,SSOCIATES, ~NC, SAMPLE TYPE 'U = Undisturbed Drive Sample C =.Chunk Sample 'B = Bulk Sample HIDDEN MEAPOWS NORTH CB 6/26/g~l 110244, PLATE NO •. 7 j , ~ BORING NO. 7 ", /. '8"~ ~E ~g H e:..> ELEVATION:,---BORING DIA.-------. ,~ t:;) ~ . ' ~,""~,~~~ ~ ,,0 OJ H, ~ H'H iii H C 0 E-I p.. rJl ~ DESCRIPTION ~ ):l~,~,tl e:..> He -Dark Brown, Wet to Saturated to -Wef, Clayey Ss.nd & Clay 2 - -Bag 4 _ - 6_ Rust Tan, Wet, Medium to Loose, Clayey Sand - 10- ------ -:- - ---,:..... ,- -- --- :! - End of Boring -, --- ---- KEY BLOW COUNT K = 3" O.D. Sampler, Kelly bar of drill rig drop, l' per blow. L -3'~ O.D. Sampler, 140lb. hammer, 30" drop S = Standard Penetrometer SAMPLE TYPE U = Undisturbed Drive Sample C =.Chunk Sample B = Bulk Sample " ' SHErAilDSON E~EEflI~ ASSOCIATES. INC. HIDDEN MEADOWS NORTH' CB 6/26/81 110244-PL.c\.TE, NO.8 2" 4 6 8 12 4 6 8 '/ 10 12 TRE~CH 1 Dark Brown Black, Humid, Medium to Loose Clayey Sand \ Brown to Dark Brown, Moist, Medium Dense Clayey Sand & Clay Tan Brmm to Buff Tan) Moist, Medium Dense Very fine Clayey Sand, BOTTOM OF TRENCH TRENCH 2 bark Brown Black to Dar"k Brown, Humid to' Moist Hedium to Loose, Clay~y Sand, &, Cl~y Buff to Tan Moist to ~vet,_ Medium' Dense, Clayey and Silty Sand 'ran to Gray to Blue Grayy Moist tc), Wet, Medium Stiff to Medium Dense, Clay '&, Silt BOTTOM OF TRENCH HIDDEl~ HEADQWS NORTa SHEPARDSON ENGINEERING ASSOCIATES. Inc. BY DATE CB Q/I0/8l ~. NO. 110244 PLATE N'),' Mi' ',.,:-, ", '}h'; 9' " .. 2 ,4 / 6 8 10 12 , TRENCH 3 Dark Brown to Black, Humid to Mois,t. Medium Loose to Medium Dense, Clayey Sand Buff to Very Light Tan, to Gray; Moist to VIet Hedium Dense, Clayey & Silty Sand BOTTOM OF TRENCH TRENCH 4 Dark Brown Black, Humi'd to Moist ,~ledium to Loose, Clayey & Silty Sand Brown Moist to Wet, Medium Dense Clayey Hand· Light Tan Mois't to Wet, Medium Dens'e Silty Sand Buff to Gray Moist, Hedium to Dense Silty Clayey Sand BOTTOM OF T~ENClt 1) HIDDEN'MEADOWS NORTH ", 16 2 .' ,-" , SliEPARDSON ENGINEERING ASSOCIATES, Inc. BY , . DATE 6/10/81 CB' NO .. 110244 PLATE NO. . 10 ' " " ' -, -... , ;'1 , . ", . . " .l."::..::.". ",='='=-::--==-__ =":::::":'. __ • ..:..:.-_ ... _ 2 .'. 4 6 TRENCH 5 Very Dark Brown, H~id to Wet, Medium Loose to Medium Stiff Clayey Sand & Clay D r190.4 , Buff to Light Tan " Moist to Wet, l>fedium Lopse, 9'Z.~,9t . Clayey Sand ,...,..---,.-.-::-, ...... -- ,M ·.20.,,~: Bright Buff Tan, Moist to Wet, Medium Dense: Silty Sand' 8 Light Gray, Moist, Medium Stiff, Clay & Silt lO __ ~~~ __ ~ ______________________________ ~_ 2 4 6 8 10 Very Light Tan, Moist to We.'t, Medium Dense Silt Sand BOTTOM OF TRENCH TRENCH 6 Dark Brown Black, Iiumid to Moist, Medium Loose, Clayey Sand Light Tan to Gray Tan, Moist " Medium Stiff Very Fine Silty Claystone, Fractured Gray to Buff Moist, Medium Stiff Claystone Fractured Sandy --~~~~--~----------------------------------~- BOTTOM OF TRENCH SE. HXDDEN MEADOWS NORTH, SHEPARDSON ENGINEERING ASSOCIATES, Inc. BY CB DATE 6/io/81 ",' NO. 110244 , :?tATE NO', ll: .-'i'_ , , " ('; , ,-/ 2 4 6 8 10 '" 4 6 8 10 E " TRENCH 7 Very Dark Brown, Humid to Wet, Hedium Loose to Hedium Dense, Clayey Sand 99'.6 t, Light Tan to Buff;. Hoist, Medium Dense, Very Fine Clayey Silty Sand Gray Moist, MediUm Stiff~ Fine Silty C~aystone Grads into Clayey Siltstone Buff Tan, Hoist tq Wet, }1edium Dense, SHty Salid Light Gray, Hoist to Wet, Hedium Den.se, Poorly Graded Clean Sand BOTTOM OF TRENCH TRENCH 8 Very Dark Brown to Bro,wo" Humid to Moist, Medium Loose, to Medium Dense~ Clayey,Sarid: Brown to Gray, Moist to Wet, Medi~ Delise to '92.8,· Stiff, Sandy Clay to Clayey Sand '~~.4 Buff Tan' Moist to Wet Medium Dense Silty Sand, BOTTON OF TRENCH HIDDEN MEADOWS NORTH;, z,t, 16: . .7 22,2' SHEPARJ?SON ENGINEERING ASSOCIATES, Inc. CB, 1 110244' PLATE NO. ;t-2, , I " .'" ' ; -..., ";""'.--'t,.!...:'(.:~' _. ~ -o;:.."",-~=------=.,..~~--._ "., ~--=-==-;.-=:--=-_::..-.:..,,--: .. _._~, _-~-G:"~~"',"~.4'_~\":;. __ ...... :: __ ~-=-_.=..:::;.-~-::-. ____ ,,~.=_::6..:::=".~.::.~~_.,~' __ ~ ... ........ ~1 >. ? \ TRENCH g. 1M " '. 2 4 ,'. - :6 E Darlt Bt:oWn.:to· -B~own.;: 'Hois.t; :"H~4·tuni:.to Loose' Clayey: Sand' &"(;1aY>., ~,~, ':;., -r",;. (1;9it~ 0 Light Tan, ,'.Humid<toi'l..fois t ,: :~1ed.i.umDto&llQoiiez Y .. Silty'·Aa§ly~y::San~ .:.'m:!. . Pal~ .Brue::;Green:~io:;·B~o~;'=to",:Pale:~Gi:e~n ,:td/-Bll1i-,,£'2: Tan;:::Ho:i1st, .,fvB,(jii~:=SHi1f9·-:-,elay & Silt ' .\. i '< :. • ' • ,.1, ~ BOTTOM OF TRENCn ...... ~~. '::.' >.1 TRENCH. 10 ~~¥t: ~~ 1?l~~~ tai":lit~wr;~' RUnii'd: ~tAO~ :~t~at:;~ .. ~::. -.~-. "~: .. :~ ; 'l1~~14,Jll: 4~:q,&-.~~ to: .. Medium:. D~s5,.; C,1':a;y:ay.. Sand{ and', eTay'" , . '-~, . ' . / :\:0:9:'13 Buf-1:< Tan, Ho'is.t,: .(HEkii'ilixl~, D'eIis~ ~ ~ ':tl''t~yet>~'~na, t.1 , '" ._.tl._>."; '4:":~;:"T",;' \-:J~'~--~J".-:'~::.:.: .• !-;~" ~.~n:: ... ~~. ,',. .' .. ' BOTTOM OF TRENCH' ." , .. ~. . !v .' HIDDEN MEADOWS NORTU SHEP~RDSON ENGINEERING ASSOCIATES, Inc. BY-,DATE CB NO. 110'244 ~ --' .. ~.~,-.-""-.'! 26,11 " , , :~~ , < ,'.', fJ OIRECT SHEAR liS)" RESULTS ,", " . • • ~~.~ 0 .~, ~~.~~: ',' '~~~~'"$ "':' ~. ,!~~----... , ..... --.=.=.~.=~~-~._~,_=~.,,~=.'~.: .. , .• ~===,....=== .. _-.. ~,_',', -;--:4-··._ • Angle of ,COhesion SAMPLE: OESer? IPTION Internal IOte,.c~pt . fhc~I~('· ) (pst) B1 @ -21 Gray & Orange Clayey Silt-Silty Clqy <> 3-7 '400 , B1 .,@ -36 Gray & Orange Clayey' Silt~Sil,ty Clay 31 359' .. B2 @ -6 Light Gray & Qrange Clayey Silt 39 500 B2, @ -16 Light Gray & Orange Clayey Silt 4'0 35() .' . l ., MAXIMUM DENSITY a OPTIMUM MOISTURE CONTENT ASTM METHOD. Maximum Optimum SAMPLE 'DESCnlPTION Density (pd), Moisture Contcryt ..c.!.~ Bl @-6 to',-7' Gray & Orange Clayey Silt 112.5 15.3, Bt @-14to-15 Gray & Orange, Silt 105'.6 17.3 at @-22to-23 Gray & Orange Silty Clay . 1-99. j , 18,.5 B1' .. @-1' to -2 Brown Sandy Clay 1-14.0 ' :' 14.2 .. EXPANSION TEST RESULTS .. SAMPLE Bl @ B1 @ Bl @ B1 @ 'B,l @ 141 to 151 -36' ;...1' to."-2' -6 ' to ~71 1-22' 'to -23 ... 1"' CONDITiON REMOLD PNDISTURBED REMOLD REMOLD REMOLD INITIAL M.C (ele) 6.8 6.0 6.1 6 2 ' .n 0 ' ' INITIAL OENSITy(~f) 11-1.3 123.5 118.8 116.1 116.5 " .. -, . FINAL M.C. (.,.) 32.1 30.5 29.7 ... 24 .• 4' 30.2 . .. Nom.~AL srne:ss (~f.) 150 150 150 150 " 150. ' . - e.XPANSION ,e/.) 8.5 14.9 14.7 4.4 12.4 .. !. . ' .. , ~E~ .. .. -1/5/81. ' . IW KLS DATE , " JO ..... '110244' ! PJ;,ATE NO.14 SHEPARDSON ENGlNEElUNG ASSOCIATES. Imi , SAMPLE DESCRIPTION Angl~ of CohltSIOn, Internal InterG~pt friction ( • ) (pst) T5 @ 4.5 to: 5. ( Buff to Light Tan Clayey Sand ,1, 22. 450 T6 @ 3.5 to 4.0 Gr~y Tan Silty Clay 32: 350 TS @ 6.5 to 7,5'Brown to Gray Sandy Clay ~ Clayey San~ 22 600 ' . ,. .' , , " MAXIMUM DENSITY a OPTIMUM MOISTURE CONTt:NT ASTM METHOD SAMPLE DESCRIPTION tr2 @ 7 to 8 Tan to Gray Silty Clay rr6, @ 3.5 to 4.0 Gray"Tan Silty Clay EXPANSION TEST RESULTS . SAMPLE T 2 @ ·1 '7 to 8' T 5 @ T 7 @ 3.0 to 4 ~o· ~ '1.0 to 1.5 CONDITION Remold' Undisturbed Undisturbed IN,ITIAL' M. C ( oJ.) 6.7 5.3 5.9- INITIAL OE'NSITY(pct) 9S.S 100.4 99.6 FINAL M.e. (0'.) 34.8 29,6 23~7 NonMAL STnESS (p~f) 166 l6~ 150 . E.XPANSION (.J.) 18.0 14;9 15;0 .. '. .., . I<LS . , T 8 @ Maximum Op\li"num Density' (pen Moistur~ '. Con~Q!f1t(OI.i 11:3':5 B 2 @ ' 4.5 to 5.0' 2.0 to' 3.0 -, . , . ' Undis turbed Remold· 5.2 6';2 , ' 9Z.S 119.4 " . 31,& .29.7, " 150 150 8A 1..7 Ol,TE ·6./29/81' '." , " - J08 NO. 110244 ,SHEPARDSON ENGINEERING ASSOCIATES. Inc: ~,_....i.' ______ ..... -------~-... PLAT,E NO. 1.5 \ I j .... w·~ 10--.. .3g -. --- I I· , I '" .. ~ ~.3..!Z~ ~ -- I I I Welded Wire Mesh as recommended in report (TyP) BY -, SHEPARDSON ENGINEERING ASSOClATES.ID~. JOB NO. Var iou~ .'. W 5-'/D--, - \lCf'2 .~ca -- ;. . 1 : I . i DATE. F • ',' ~rn~ M1d~AL- . aHh , 1'y~ y.~4' ~ , ~~ a,f>~ l.o~~ .. ~AW"~ IN-1~ ~'~1c.A11~ .,~~ 'N~ .S=A\ ~-. . . SHEPARDSON ENGINEERING ASSOCIATES., Inc. ~, r , . u" ~OfUd'tO ~14t", ,f?I.v. ff~ ~ ~ -, - APPENDIX A, PAGE 1 JOB NO. 110244 Gf;NERAL . INTENT RECOMMENDED GRADING SPECIFICATIONS GENERAL PROVISIONS DATE 7/13/€H· The intent of these specifications is to establish procedures fot' clearing and compacting fill soil to the lines and grades shown on the· accepted plans. The. recommendations contained in ,the preliminary. s.oil investi- gation report and/or the attached Special Provisions 'are a part of the Recommended Grading Specifications and shall supersede the' provisions contciined hereinafter in the case of coriflict. INSPECTIO~ AND TESTING A qualified soil engineer shall" be employed to inspect and test' the earthwork in accordance with these sp~cifications. It will be necessary that the soil engineer or his representative provide adequate .inspection so' that he may state his opinion that the work was:. ()r w~s not accomplished . as specified. It shall be the responsibility of the con- t~actor ·to assist the engineer and to keep him appraised of work schedules, changes and new information and d~ta so that he may . document the basis for his opinion. , If, .. in the. opinion' of the soil engineer,' substandard. . conditions are'" encountered '(such as questionable soil, poor moisture content, inadequate. . ... :. compaction, adverse weather, etc.), he, win recommend, that it be' . corrected or recommend rejection of the work. . Soil tests used to determine the degree of compaction will be performed in accordance with the following American Society for' Testing an<l Materials test methods: Maximum Density & Optimum Moisture Content: A.S.T.M.P.;.1557..:.10 Density of Soil In-Place: A.S.T.M.D-1556:-64 -PREPARATION OF AREAS TO RECEIVE FILL . All vegetation, brush and debris shall be removed" piled and burtlec;!" or 'otherwise disposed of. After. clearing, the natural grotllld' shall be.' scarified to a depth of six inches, brought to the proper. moistu:r;;e. content, compacted and tested for the minimum density specified .in the. Special Provisions of the recommendations contained in' the prelimInary soi~ iilvesti~ a tion report. When the slope of the natural ground receIVIng fill exceeds 20 percent (5 hori.zontalunits to 1 vertical unit)., the original ground shall be stepped or benched. Benches shall be cut to a firm' competent soil condition. .. "1 / fi ~,I :-.' , \l'i ~~~-====-,_.J:,...~-:-:-~,=-.~=':.. .. :~-.~ ....... -..:. ~_.::=:.-:; ...:~..:..=:_~::: ___ --:=::-....:.."'-::.: ..;..~~=. APPENDIX A, PAGE 2 JOB NO. 110244 DATE ---------7/13/81 The lower bench shall be at least ten feet wide and. all other 'benches 'at least six feet wide. The horizontal port~on of each benc;:h shall be compacted prior to receiving fill as specified hereinbefore for' compacted natural ground. Ground slopes flatter than 20 percent shall be benched when considered necessary by the soil engineer. FILL MATERIAL Material placed in the fin shall be approved by the soil engineer a:~d shall be free of vegetable matter an.d other deleterious substances. Granular soil shall contain sufficient fine materials to fill the voids. The definition and disposition of oversized rocks, expansiye and/or detrimental soils are covered in the Special Provisions. Expansive soils, soils of poor. gradation or strength characteristics, ma'y be thoroughly mixe,d with other soils, to provide satisfactory fill materials but only with the explicit consent of the soil engineer. ' PLACING AND COMPACTION OF FILL Approved fill material shall be placed in areas px:epared to receive fill in layers not to exceed six inches in compacted thickness. Each layer shall have a uniform moisture content in the range that will allow the compaction ,effort to be efficiently applied to a'chieve the specHied degree of compaction. Each layer shall be uniformly compacted to' a mInImum specified density with adequately 'sized equipment, ,either speCifically designed for soil compaction or of proven reliability! The minimum degree of compaction to be achieved is specified: ip either the Special Provisions or, the recommendations cont~ined in the prelirqina-ry' soil investigation report. 'j " SEASON LIMITS Fill shall not be placed during unfavorable weather· conditions'. When work is interupted by heavy rains, filling operations shall Aot be resumed until ,the proper moisture content and density of the fill ha~ ,been ,achieved. Damage resulting from weather shall be repaired ,before acceptance of work. ·UNFORESEEN CONDITIONS In the event that 'conditions are encountered during th~' site prepar~tioll and construction that were not 'encountered d4ring the preliminary soil ~nvestiga:tion, SHEPARDSON ENGINEERING ASSOCIATES" INC. should, q~' notified immediately to permit evaluation and' submittal of alternative recommendations as required. We s.hould also be notified of any signHi- cant chang~s in the proposed site grading. ,:' :', : ' .. ," APPENDIX" B JOB NO. .• "~.~.,~~-..................... ",-".' "~"I' .. 110244, DA t E 7/13/81 I RECOMMENDED GRADING SPECIFICATION$ , SPECIAL PROVISIONS The minim~ degree of cOmt~ction to be obtained in compacting, natural ground, in the compacted fi 1 and in the compacted b,ackfiU, shall be, 90 percent. , Detrim~ntally expansive soil fs defined as soil which will swell more than 3' percent against a pres!:?ure of 150 pounds per' square foot fr.om a condition of 90 percent of maximum dry density and optiml,lm m()istuJ;e content to saturation. , Oversize fill material is defined as rocks or lumps' over six' inches in ,diameter. At least 40 pe'rcent of the fill soil shall pass through a #4-u.S. Standarcl Sieve. ;.>,' , -.~- ' .. ' .' -.', ' SOIL DESCRIPTION GROUP SYMBOL TYPICAL NAMES ,COARSE GRAINED -More than half of material is larger than No, 200 sieve size. GRA VELS -More than half of coarse fraction , is larger than No. 4 sieve size but smaller than 3". ' , CLEAN GRAVELS GRA VELS WITH FINES (Appreci'able amount of fines) SANDS -More than half of coarse fraction is smaller than No. 4 sieve size. CLEAN SANDS SANDS WITH FINES (Appreciable amount. of fines) FINE GRAINED More than half of material is smaller than No. 200 sieve size. SIL TS AND CLAYS (Liquid Limit less than 50) SIL TS &: CLAYS (Liquid Limit greater than 50) HIGHL Y ORGANIC SOILS GW GP GM Well graded gravels, gravel-san4 mixture~, little or no tines~ Poorly grq,ded gravels', graver sand mixtures,Uttle. or no f~hes. Silty gravels, poorly' graded gravel':' sand~si1t mixtures. . GC Clayey gravels; poorly graded gravel ... ·· . sand, clay mixtures.. . SW SP SM Well graded sand, gravelly sands, little or no fines. Poorly graded sands, graveily sands, little. or rio fines~ Silty sands~ poo,rly'grad~d sandanc;f silt :', mixtures.' , . ',' . SC Clayey sands, poorly graded sand and: clay mixtures. ML Inorganic . silts and very fine sands,. rock flour, sandy, silt qr' clayey-silt-: sand mixtures with slight plasticity. CL Inorganic clays of low to medium.' ': plasticity, gravelly clays, sandy clays, ~ silty clays, leah clays. ," PL Organic: silts ahdorgani<i:' silty ~lays <if low plasticity • MH . Inorganic , silts, miGaceous, or diatomaceous fine sandy or siltY'soils, . elastic silts. . . CH Inorganic, clays of' high plastiCity, fat clays. OH OrganiC' ciays of.· inedi~m to' high: plasticity~" . PT' Peat and other highly organic soi1s~