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Home My WebLink About; Costa Real Municipal Water District Expansion; Soils Report; 1987-03-30- WESTERN SOIL AND FOUNDATION ENGINEERING, INC. - PHONE 74c3553 423 HALE AVENUE AREA CODE e,* ESCONOIOO. CAIIFOF1NIA 9202.5 - - March 30, 1987 COSTA REAL MUNICIPAL WATER DISTRICT - 5950 EL Camino Real Carlsbad, CA 92008 - Attention: WILLIAM E. BLAKESLEY Re: OUR PROJECT NO. 86-93 - Headquarters Expansion Project C.R.M.W.D. Project No. 86-107 5950 El Camino Real - Carlabad, California Subject: ADDENDUM NO. 1 TO OUR RePORT OF PRELIMINARY SOIL INVESTIGATION - Mr. Blakesley: This report presents the results of our Addendum No. 1 to our Report of - Reliminary Soil Investigation, dated January 30, 1987. Addendum No. 1 consisted of three additional test pits in the vicinity of the rectangular -~ shaped proposed and future buildings situated parallel and near the western property line. The test pit locations are shown on Plate Number 1A - The new test pit numbers are T-9, T-10, and T-11. (Plate numbers 11, 12, and 13, respectively.) - The soil in the vicinity of the three new test pits consisted of loose to - medium dense, very moist to wet, brown clayey sand and sandy clay to depths ranging from 1 to 3% feet below existing ground surface. - - ENGINEERING DEf’T. LIBRARY CiZyof Cartsbad 2075 Las Palmas Drive caflsbd CA 92009-4859 - - Underlying the sandy clay and clayey sand was medium hard to very hard, moist, light brown to orange siltstone to at least the depths investigated (7 to 9% feet). The siltstone became difficult to excavate with a 580 C backhoe at depths ranging - from 7 to 9b feet below existing ground surface. - A sir inch thick layer of very dense quartsite was encountered in test pit number T-10 at a depth of 5 feet. - Free groundwater was not encountered in any of the test pits and no seeps - were observed. For reconnnendations and conclusions, refer to the Report of Preliminary Soil - Investigation, pages 3 through 6, inclusive. - Test pits T-9 through T-11 were made on February 19, 1987. -. The depths of removal at each test pit location are shown on Table lA, attached. - In our Preliminary Soil Investigation report, foundation and slab-on-grade recommendations were made. Considering the very high expansive soils, two alternatives to these recommendations are given as follows: - - - - .- First, selective grading may be used in order to keep the expansive soils from being placed in the upper four feet of the building pads. Then the near surface soils may be tested to determine their potential expansion. Foundation and slab recommendations may be made based on test results obtained. Footing and slab requirements may be reduced accordingly. A second alternative would be to import non- expansive soil (expansion potential of 4 percent or less) and place into the upper 4 feet of WESTERN SOIL AND FOUNDATION ENGINEERING, INC. .- - - building pads within the perimeter of 5 feet beyond the building perimeters, The building perimeter would include all concrete slabs - and walks. _ The upper two feet of parking areas may be treated similarly in order to increase the Resistance “R” Value of the near surface soils and thusly decrease the structural pavement section. - If you have any questions after reviewing the findings and recosssendations contained - in the attached report, please do not hesitate to contact this office. This opportunity to be of professional service is sincerely appreciated. - Very truly yours, WRSTFRN SOIL AND FOUNDATION ENGINEERING, INC. -~ -@F- - DENNIS E. ZIMMRMAR RCE 26676 DEZ:ch - Attachments: Table 1, Test Pit Logs Distribution: (8) Addressee WESTERN SOIL AND FOUNDATION ENGINEERING, INC. - - - - - - - .- g E 3 1 . . 2 . 3:: . 4. . 5. I 6. . 7- m 8- - 9- m LO- - e A i 3 T I : - - - - - 1 .j $! 3j 4 I i - - TV&CR NuuJcc T-9 8hfJtfD8 298 DESCUIPTI# Brown Clayey Sand/sandy clay k Light Brown Siltstone Orangish Brown Siltstone Brown Ironstained Siltstone Quartzite Brown Ironstained Siltstone Difficult Digging with 580 C Backhoe at 9'-0" Bottom of Test Pit at 9'-6" Wet Moist Moist Moist Dry Moist -- ,oose :ed. .ard ,ard ry Ha 3-y ,ard g& 2; e*Y ense -- i ~;~4,9~f;y,E:pcpsion SUBSURFACI! lX?LORAtlON LOG Reject NA.'8i-i07 LOO@- BT: DZ DATJ mooeD: v,,o,g, I JOJ NUYIRR: 86-93 I Plate No. 11 - - -. - - - - - - - - - - Y s E : . 1. . 2. 3. . 4. m 5 - I 6, s 7, w B- i : - - - - - T&3 WUWtl T-10 ncv~tfm 301 DESCRIPTI# ~“over 4” Base ram clayey Sand/ andy Clay ,ight Brown and #range Layered and esicated Siltstone rang&h brown iltstone suartzite rangish Brown iltstone &tom of Test Pit at 7’-6” Wet Very rioist Floiit Dry Xoist LOOSC 4ed. $ard zz iea3 Ez $ard Jery iard c’ 5 8. t: .! z m .a 8 - f: Z!: :: e SUBSURfACE tX?LORAtlON LOG LOOOCO l T: DZ OAT1 maa~w/l9/07 ~001 muu818: 86-93 Plate No, 12 l- 2-. 3- 4- 5- 6- 7-- 8- e e t - - - t’ka WLe T-11 mvrtml 300 DESCRIPfI# fr”AC over 4” Base rowrt Sandy Clay/ ’ layey Sand lrangish Brown lesicated Siltstone lrangish Brown ,iltstone &tom Of Test Pit At 7 * -0” ‘ery [oist iois t loist Zoft lard/ Loose to Me Jense Med iu Hard Hard Very Hard t f : &’ 8 SUBSURfACI EXPLORATION LOG - - -. - TABLE 1A BEQIJIBED DEPTH OF REMOVAL TEST PIT NUMBER T-9 T-10 T-11 DEPTH OF REMOVAL AT THIS LOCATION (FEET) 3 5 5 SOIL AND FOUNDATlON ENGINEERING, INC. _~ - - -~ -- - - - - - - - WESTERN SOIL AND FOWNDATlON ENGINEERING, INC. PHONE 746-3553 423 HALE A”ENV.5 ARE.4 CODE 619 ESCONDIDO. CALIFORWIIA 920.25 January 30, 1987 COSTA REAL MUNICIPAL WATER DISTRICT 5950 El Camino Real Carlsbad, CA 92008 Attention: WILLIAM E. BLAKFSLEY BE: Job No. 86-93 Headquarters Expansion Project C.R.M.W.D. Project No. 86-107 5950 El,Camino Real Carlsbad, California 92008 SUBJECT: Report Of Preliminary Soil Investigation Mr. Blakesley: In accordance with your request, we have completed a preliminary soils investigation for the proposed project. We are presenting, herewith, our findings and recommend- ations. The findings of this study indicate that the site is suitable for the proposed development provided the special site preparation and foundation reconrmendations presented in the attached report are complied with. If you have any questions after reviewing the findings and recormnendations contained in the attached report, please do not hesitate to contact this office. This opportunity to be of professional service is sincerely appreciated. Very truly yours, WESTERN SOIL AND FOUNDATION ENGINEERING, INC. DEZ: ji Attachments - Distribution: Addressees (8) TABLE OF CONTENTS - -~ - - - - - - - - Introduction and Project Description Project Scope Findings Site Description Groundwater Recommendations and Conclusions Site Preparation Field Explorations Laboratory Testing Limitations Table I Plate Number 1 Plate Number 2 Plate Number 3-10 Plate Number 11 APPENDIX Existing Fill Imported Fill Surface Drainage Earthwork Cut and Fill Slopes Rippability General Transition Areas Lateral Resistance Retaining Walls Footing Observations Asphaltic Concrete Pavement PAGE 1 1 2 2 3 3 3 3 3 4 4 4 4 4 4 5 5 6 6 ATTACHMENTS Removal Depths Plot Plan Unified Soil Classification Chart Trench Logs Laboratory Test Results Grading Specifications and Recommendations WESTERN SOIL AND FOUNDATlON ENGINffRlNG, INC. .- - -- - PRELIMINARY SOIL INVESTIGATION HEADQUARTERS EXPANSION PROJECT C.R.M.W.D. PROJECT NO. 86-107 5950 EL CAMINO REAL CARLSBAD, CALIFORNIA 92008 - - Prepared For: COSTA REAL MUNICIPAL WATER DISTRICT 5950 EL CAMINO REAL CARLSBAD,CA 92008 JOB NO. 86-93 JANUARY 30, 1987 - WESTERN SOIL AND FOUNDATION ENGINEERING, INC. - - -~ -~ -. - - - -. _. - - - PRELIMINARY SOIL INVESTIGATION HEADQUARTERS EXPANSION PROJECT C.R.M.W.D. PROJECT NO. 86-107 5950 EL CAMINO REAL CARLSBAD, CALIFORNIA, 92008 INTRODUCTION AND PROJECT DESCRIPTION This report presents the results of our preliminary soils investigation for the proposed Headquarters Expansion Project. It is our understanding that the proposed construction will consist of three new structures. All are proposed to be of masonry construction. Building A is to be a lOO’x150’ warehouse located in the southeast quadrant of the site. It is suspected that this site may be in the uncontrolled fill area. Building B is a 4O’xlOO’ shop building located in the northeast quadrant; and Building C is a 7,500 sq. ft. addition extending easterly from the existing administration building. Other site improvements yet unplanned may include a vehicle fueling facility, paved parking and work areas, storm drains and street improvements on the service road along the easterly boundary. The site configuration and test pit locations are shown on Plate Number 1. PROJECT SCOPE This investigation consisted of a surface reconnaissance, subsurface explorations, obtaining representative samples, laboratory testing, analysis of the field and laboratory data, and preparation of this report. Specifically, the intent of this analysis was to: a) Explore the subsurface conditions to the depths influenced by the proposed construction, WESTERN SOI1 AND FOUNDATION ENGINEERING, INC. -l- .- - - - -~ - - - - - - b) Evaluate, by laboratory tests, the pertinent engineering properties of the various strata which will influence the development, in- cluding their bearing capacities, expansive characteristics, and settlement potential, c) Develop soil engineering criteria for site grading, d) Determine potential construction difficulties and provide recormnendations concerning these problems, and e) Recommend an appropriate foundation system for the type of structures anticipated and develop soil engineering design criteria for the recommended foundation design. FINDINGS The property is irregular in shape. The site is a 6.5 acre parcel lying along the east side of El Camino Real approximately one quarter mile north of Palomar Airport Road. The westerly portion of the property is currently occupied by the District’s administrative office, a metal maintenance and operations building, a temporary trailer housing the engineering department and a paved parking lot. The easterly portion is undeveloped and is used as a pipe and materials storage area. The site slopes generally easterly at a grade of about five percent. The site varies in elevation from about 311 feet above M.S.L. in the northwest corner to about 270 feet above M.S.L. in the southeast corner. The site is covered with loose fill soils with trash, that range in depth from 1 to 12 feet below existing grade at the locations investigated. These soils are composed of fine to coarse sands and silty clays. The fill soil is under- lain by colluvial soils to depths below existing grade of 1 to 14 feet. These WESTERN SOIL AND FOUNDATlON ENGINEERING, INC. -2- - soils consist of silty clays and clayey silts. These colluvial soils are soft to stiff and very moist to wet. The colluvial soils are underlain by formational soils consisting of very moist, hard to very hard siltstone. The silty clays and clayey silts of the fills and colluvial soils are in the very high expansive range. These soils require special consideration as dis- cussed later in this report. .-~ . ..- .~. _-. -. - - - GROUNDWATER : Free groundwater was not encountered in any of the exploratory trenches and no surface seeps were observed. It must be noted, however, that fluctuations in the level of groundwater may occur which may not have been evident at the time of our field investigation. One exception is perched water at a depth of three feet in test pit Number T-5. RBCOEMENDATIONS AND CONCLUSIONS SITE PREPARATION EXISTING FILL: We recommend that any existing fill, topsoil, alluvium, colluvium, and low density soil be removed to firm natural ground from beneath proposed fill pad areas, parking and driveway areas, slabs or sidewalks so that struct- ures will be supported on firm material. This soil may be replaced, if desired, as a properly controlled fill densified to at least 90% relative compaction. All deleterious materials, trash and oversized debris encountered in this fill should be removed and legally disposed of off-site. Based on the findings of this study, it appears that the maximum depth of removal and recompaction of the native soils will be on the order of 15 feet. The actual depths of removal will vary from 3 to 15 feet. The actual depth of removal at each test pit location is shown on Table I, attached. The horizontal limits of these recommendations should include the area within the perimeter of 15 feet beyond the exterior of any buildings, pavements, walks or other improve- ments. All areas to receive asphaltic or Portland cement concrete pavements, slabs or sidewalks should be treated similarly. IMPORTED FILL: Imported fill, if required at this site, should be examined by WESTERN SOIL AND FOUNDATION ENGINEERING, INC. -3- -. -- -~ - - - ._ - - SOIL AND FOUNDATION ENGINEERING, INC. - our office to determine their suitability prior to importing these materials. SURFACE DRAINAGE : Surface drainage should be directed away from the structures and ponding of water should not be allowed adjacent to their foundations. EARTRWORR: All earthwork and grading contemplated for site preparation should be accomplished in accordance with the attached Recommended Grading Specifi- cations and Special Provisions. All special site preparation recommendations presented in the sections above will supersede those in the standard Recommended Grading Specifications. All embankments, structural fill, and fill should be compacted to a minimum of 90%. Utility trench backfill should be compacted to a minimum of 90% of its maximum dry density. The maximum dry density of each soil type should be determined in accordance with A.S.T.M. Test Method 1557-78, Method A or C. CUT AND FILL SLOPES: We recommend that cut and fill slopes be constructed with a slope ratio of 2.O:l.O (horiaontal:vertical) or flatter, to a maximum height of 20 feet. Slopes should be planted as soon as feasible after grading. Slope erosion including sloughing, rilling, and slumping of surficial soils may be anticipated if the slopes are left unplanted for a long period of time, especially during rainy seasons. Erosion control and drainage devices should be installed in compliance with the requirements of the controlling agencies. RIPPASILITY: All soil material exposed in the test pits (trenches) can be excavated by conventional means. FOUNDATIONS: Considering the expansive soils in the very high range, the structures should be supported on continuous footings bearin, in compacted on-site soil material at a minimum depth of 24 inches. Footings may be designed for an allowable dead plus live load bearing value of 1500 pounds per square foot. These values may be increased by one-third for short-term loads, including wind or seismic. Footings should have a minimum width of 12 inches. Due to WESTERN -4- - _- - - - - - -~ - - - - - - the very highly expansive soils, all continuous ,footings should contain at least four #5 reanforcing bars, two top and two bottom. Settlements under building loads are expected to be within tolerable limits for the proposed structures. Concrete slabs-on-grade may be supported on compacted soil material. Due to the highly expansive soils, five inches of clean washed concrete sand should be placed beneath the slab. Slab reinforcing should be provided in accordance with the anticipated use of and loadings on the slabs. As a minimum, due to the highly expansive soils, the slabs should be reinforced with #A bars at 15 inches on center both ways located at mid-height of concrete slab. The slab should be a minimum of five inches thick. In areas where moisture-sensitive floor coverings are to be utilized and in other areas where floor dampness would be undesirable, we recommend consideration be given to providing an impermeable membrane beneath the slabs. The membrane should be covered with 2 inches of sand to protect it during construction and to allow the concrete to cure properly. The sand should be lightly moistened just prior to placing the concrete. Care should be taken not to puncture the visqueen. All joints (laps) in the visqueen should be a minimum of 6 inches in width and sealed with an approved sealer. TRANSITION AREAS : Foundations supported partially on cut and partially on fill are not recamnended. The tendency of cut and fill soils to compress differ- ently can frequently result in unequal structural support and subsequent crack- ing to portions of the structure. Therefore, in transition areas, we recommend that the entire cut area be overexcavated and replaced with soils compacted to a minimum of 90%. This overexcavation or undercutting should be carried to a depth of 3 feet below finish subgrade. LATERAL RESISTANCE: Resistance to lateral loads may be provided by friction at the base of the footing and by passive pressure against the adjacent soil. For concrete footings on compacted soil a coefficient of friction of 0.30 may be used. An allowable passive uniform pressure of 250 pounds per square foot WESTERN SOIL AND FOUNDATION ENGINEERING, INC. -5- per foot of depth acting against the foundations may be used in design. - - - -. - - - - - - - If footings are proposed adjacent to slope areas, we recommend that the footings be deepened to provide a minimum horizontal distance from the outer edge of footings to the adjacent slope face of one-half the height of the slope. The minimum and maximum distances should be 8 and 12 feet, respectively. RETAINING WALLS: Retaining walls must be designed to resist lateral earth pressures and any additional lateral loads caused by surcharge loads. We recommend unrestrained walls be designed for an equivalent fluid pressure of 35 pounds per cubic foot (pcf) where backfill is level. We recommend restrained walls be designed for an equivalent fluid pressure of 35 pcf plus an additional uniform lateral pressure of 6~ pounds per square foot where H=the height of backfill above the top of the wall footing in feet. Wherever wall will be subjected to surcharge loads, they should also be designed for an additional uniform lateral pressure equal to one-third the anticipated surcharge pressure in case of unrestrained walls, and one-half the anticipated surcharge in the case of restraining walls. The preceding design pressures assume there is sufficient drainage behind the walls to prevent the build-up of hydrostatic pressures from surface water in- filtration. Adeqnate drainage may be provided by means of weep holes with per- meable material installed behind the walls or by means of a system of subdrains. Backfill placed behind the walls should be cuspacted to a minimum degree of compaction of 90% using light compaction equipment. If heavy equipment is used, the walls should be appropriately temporarily braced. FOOTING OBSERVATIONS: All footing excavations should be reviewed by the Soils Engineer prior to placing reinforcing steel and concrete. ASPBALTIC CONCRETE PAVEMENT. The asphaltic concrete pavement section should be designed by our office. During the earthwork operations, we should sample the subgrade soil material, perform R-Value tests, and design the pavement section accordingly. WESTERN SOIL AND FOUNDATION ENGINEERING, INC. -6- .- _- - -- - - - - - - - - FIELD EXPLORATIONS gillbe ghbniarface explorations were made at the locations indicated on the acEahPd PI&e Number 1 on January 6, 1987. These explorations consisted of trcnch+s dmg by means of a blackhoe. The field work was-conducted under the obsar&iOP Of our geology and soil engineering personnel. ‘l& explortiions were carefully logged when made. These logs are presented on the followimg Plate Numbers 3 through 10. The soils are described in accord- aDce with tfhe Unified Soils Classification System as illustrated on the attached eimplified chart on Plate Number 2. In addition, a verbal textural description, the wet color, the apparent moisture and the density or consistency are presented. The density of granular material is 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 hard. Samples of typical and representative soils were obtained and returned to the laboratory for testing. LABORATORY TESTING Laboratory tests were performed in accordance with the generally accepted American Society for Testing and Materials (A.S.T.M.) test methods or suggested procedures. Test results are shown on Plate Number 11. WESTERN SO/l AND FOUNDATION ENGINEERING, INC. -7- - - - - - The rccomendatioaa praaantcd in thie report are coatingcat upoa our review of final plana aad l pacificatioaa. The soil l agiaaar should raviav and verify the compliance of tha find plaa vith thir report and with Chapter 70 of the Uniform BuildinS Code. It is rcc-nded that Uaatern Soil and Foundation Engineering, IIZC.) be retained to provide continuous roil engineering l arvicea during the earthwork operations. This is to obaerva compliaace with the design ctincapta, specifications or recomendationr and to allow design changes in the event that subsurface conditions differ from those anticipated prior to start of construction. The recommendations and opinions expressed in this report reflect our best estimate of the project requirements based on an evaluation of the rubsurface soil conditions encountered at the subsurface ex- ploration locations and the assumption that the soil conditions do not deviate appreciably from those encountered. It should be recog- nised that the performance of the foundations and/or cut and fill slopes may be influenced by undisclosed or unforeseen variations in the soil conditions that may occur in the intermediate sad unexplored areaa. Any unusual conditions not covered in thia report that may be encountered turing site development should be brought to the attention of the soils engineer so that he may make modifications if necessary. Thib office should be adviaad of any changes in the project scope so that it may be determined if the ret-ndationr contained herein are appropriate. This should be verified in writing or modified by a vritten addendum. The findings of this report are valid as of this date. Changer in the condition of a property can, however, occur vith the passage of time, whether they be due to natural processes or the work of mm WESTERN SO/l AND FOUNDAllON ENGINEERING, INC. -B- _- - - - - - 01) this or adjacanc propartier. IO addition, changer ia the State- of-the-&t and/or Government Coder may occur. Due to ruch changer, the findinga of the report may be invalidated wholly or in part by changer bayond our control. Therefore, this report should not ba relied upon after a period of one year without a review by ua veri- fying the ruitability of the coaclurioar and reccnmnendationa. We will be rerpouaibla for our data, interpretationa, and recow mendationa, but #hall not be rerponribla for the interpretationa by othcra of the information daveloped. Our earvicar conrirt of pro- farrioaal conrultation and obrervatioo only, and no warranty of any kind whatsoever, exprerr or implied,’ ir made or intended in con- nection with the work performed or to be performad by UI, or by our propoeal for consulting or other rervicer, or by our furnishing of oral or written reportr or finding*. It ia the rerponribility of the Client or the Client’r representa- tive to enrurc that the information and recomendationr contained herein are brought to the attention of the eugineer and architect for the project and incorporated into the project’e planr and rpeci- ficationr, It ir further hir rerponribility to take the necersary measures to enmre that the contractor and hir subcontractors carry out ruch recommendationa during construction. WESTERN SO/l AND FOUNDATION ENGINEERING, INC. -‘,.- ATTACHMENTS WESTERN SOIL AND FOUNDATION ENGINEERING, INC. - - - - - - - - - - - - - - - - - SEE BACK POCKET FOR PLATE I WESTERN SOIL AND FOUNDATION ENGINEERING, INC. - - - - - - - - - - TABLE I REQUIRED DEPTH OF REMOVAL Test Pit NO. T-l T-2 T-3 T-4 T-5 T-6 T-l T-8 Depth of Removal at This Location (Feet) 6 6 6 9 3 15 7 10 WESTERN SOIL AND FOUNDATION ENGINEERING, INC. -. - - -. - -~ -~ - . EUBSURIACX gIPLORATIOU LeC37.M) UNIPBD SOIL CLASSIPICATLOU CURT SOIL DESCUPTICM GROUPSYMSOL mP1cALKAm8 I. CUNSE GRAINND, Norc alan helf of mtcriel ir Jerger then Wo. 200 ricve size. GRAVNLS CLSEAN GRAmLs More then helf of couee frection ir luger than No. 4 eievc l ixe but meller then 3” GRA~LsIiITEFINEs -(Apprecieble mount of finer) SANDS CLEAN SANDS sthen half of coerce frection ie mellor then No. 4 aiave rize. SANDSWITEIFINES (Apprecieble emunt of finer) II. FINE GRAINED, More then helf of meteriel ir smeller then No. 200 crieve #ire. SILTS AND CLAYS Liquid Limit leee then 50 SILTY AND CUYS Liquid Limit greater than 50 BIGELY ORGANIC SOILS ta CP GN GC SW SP 811 SC CL OL ml CN 08 PT Well greded grevelr, grAvel- rend mixturee, little or no finesr. Poorly peded grevelr, grevcl- sad mixture*, little or no finer. Silty grevele, poorly gredcd grovel-aend-rilt nixturer. Clayey gravel*, poorly greded grevel-rend, cley mixturer. Well greded sand, grevelly send@, little or no finer. Poorly graded oande, gravelly randr, little or no finer. Silty eanda, poorly graded mad end rilt mixtures. Clayey eende, poorly greded sand end cley mixturer. Inorganic riltr end very fine rendr, rock flour, rendy rilt or cleyey-rilt-rend mixtures with slight plert- icity. Inorgenic cleyr of low to medium plerticity, grevelly cleyyr, rendy cleyr, l ilty cleyr, lcen cleye. Orgenic rilty and organic silty cleyr of lov plerticity Inorgmic l iltye, miceceous or dietomeceour fine randy or l ilty’eoilr, el4rtic riltr; Inorgenic cleyr of high plrrticity, fet Organic cleyr of medium to high plerticity. Peet end other highly orgenic roilr WESTERN SOIL AND FOUNDATION ENGINEERING, INC. PLATE NUMBER 2 T : t’ : f ; s 1 . 1-- 2- CK BA 3- 4-- 5-- BAG 6' 7- 8- 9- lo- IL-CK L2- - , ,i ii :j , i SP - CL - L/I - L - T&NCRNVURER T-l Eltvrtltn 301.0 DESCRIPTIDR Light Brown Fine to Coar Very Sand (Fill1 Moist Brown Silty Clay Gray-Orange Silty Clay t Very Clayey Silt Moist Gray Siltstone With Iron Very Staining Moist Sttom of Trench Kcavated With Case 580 ickhoe CK=Chunk Samples BAG=Loose Bulk Sample E : :1 i : :: Very Moist +g: Z-i -=I z;: ::I 0’ Loose Soft to Mediuu Stiff Stiff Hard But Fract- ured ecomir =Y .ard : f 3; bS 0’ 95.8 100.: 25.7 91.6 .04.8 22.0 I- s - a- *= . . gi 0 25.0 z :s Ff :f: :; z 34.3 . . SUBSURFACE EXPLORATION LOG HEADQUARTERS EXPANSION PROJECT C.R.M.W.D. PROJ. No. 86-107 Lotam w: "eG* DATE LL)OatD: 1-6-87 ,0, I(uy,Im:86-93 Plate No. 3 . - T t ‘z r : : - . 1' . 2. 3- 4- 5- - 6' m 7- m 8- - 9- m lo- : : 3 1 LA - - / .i :I :: , , L - L - L - L - - TRENCH NUMBER T-2 Eltvrtion 300.5 DESCRlPTIOW ;ray Silty Clay With Roe (Fill) slack to Dark Gray Silty kganic Clay brownish-Gray Silty Clay 3rown Silty Clay (Colluvium) :ray Siltstone With Iron Stain (Formation) 3ottom of Trench excavated With Case 580 3ackhoe BAG=Loose Bulk Samples r : : i l s r i l 1 wet Jet iJet Very bioist Very Moist -8 -0’ Y’ Soft to ?tediun Stiff Mediun Stiff Mediun Stiff Mediun Stiff Hard .m ; ZY! ;:g; a-1 xi ri; :-! ! _ 107.1 106.: u* e- 2: . I zg = 0 v 23.4 21.2 UpAnQUARTERS EXPANSION PROJECT - - c.K.M.W.D. PROJ. No. 86-107 SUBSURFACE EXPLORATION LOG boo@- l T’: “.G. DATE LC)OOED: ,mhwR7 -01 wy1m86-93 Plate No. 4 r T-3 Y r : T&CH NUMBER : 5 : : i 3 :!! EtWJttOll 297.5 f :: xs 0 ; . l * : : : a DESCRIPTIDN - SP Light Brown F-C Sand ‘cry Loose - (Fill bist 1- SP Brown Very Silty Fine Sal Moist Loose CL Orange-Brown Silty Clay ‘cry Soft 91.3 ' BAG loist to Medium Stiff 3- _. (Colluvium) &-- -BAG a ale Yellow Clayey Silt ‘cry o.ft to 90.4 loist .edium 5-- ,tiff a rown-Gray Siltstone With ‘cry .ard - nterbedded Lenses of Gra: Ioist Fract- 6- ine Sandstone With Iron red) taining 7- 8- 9- lO- 11- lz?- (Formation) &tom of Trench lery 'cry foist Lard BAG-Loose Bulk Samples - L 24.2 28.2 HEADQUARTERS EXPANSION PROJECT SUBSURFACE EXPLORATION 100 C.R.M.W.D. PROJ. No. 86-107 LOQDCD BT: ".G. DATK LDQQcD:,-~-*, I 1,0, wuurrr+36-93 1 Plate No. 5 TREiCH NLMBER T-4 Elcvrtton 294.0 : - * F . f ; E a a : : 2- BA 3- 4-- 5- 6- 7- 9- Lo- ll- 12- - Jft tc odium riff P :: Ef - u iz = 8 :: ., ’ t: :: l . 2;; . l a DESCRIPTIDN Olive Brown Silty Clay Very With Fragments of Silt- Moist stone and Chunks of Asph. to alt wet (Fill) ark Gray Clay Wiih Decom. wing Organics (Colluvium) 'e t -5 St . . - c :x : CL - :Ljo; 87.0 25.0 .04.0 25.0 rown-Gray Silty Clay Wit1 inor Organic Material 'et 0 cl-y oist :dium riff (Colluvium) ray Siltstone With Iron taining.Bi-Valve Impress- on IL I cry .oist wd try lrd (Formation) (Formation) Bottom of Trench urn of Trench Very Slow Digging With Slow Digging With Case 580 Backhoe 580 Backhoe 1 BAG=Loose Bulk Samples -Loose Bulk Samples HEADQUARTERS EXPANSION PROJECT C.R.M.W.D. PROJ. No. 86-107 . SUBSURFACE EXPLORATION LOG Looam BT: "*G* DA11 L008ED:l-6-87 ! JOB nt~~~cn: 86-93 plate No. 6 . 1. . 2’ . 3- 4- . 5. . 6’ - P a 8- - : ,z ;i ‘i : a b -r r&x NWB&R T-5 ,t* 2 l f: 8c ts#- i t -2 ttcvrtlon 303.5 YI 2s b’ -Is i : f- 2;: t DZ c 8 ta' \ OW . . -8 :,‘a ; ** x z;: = 0 DESCRIPTIDR VC 1 2 v Dark Brown Silty Fine ro very Loose Coarse Sand (Fill: Moist L Gray Siltstone Very Hard (Fragmented) Moist . - 4:: zz tz :E a :- Perched Water at 3' Less Fragmented at .4' (Formation) - ottom of Trench ?ry Slow Digging With ase 580 Backhoe ety ard SUBSURFACE EXPLORATION LOG RallON LOG HEADQUARTERS EXPANSION PROJECT C.R.M.W.D. PROJ. No. 86-107 LOOOKD BY': "*G. DATE LDoow1-6-87 OATL ~~00~1-6-87 a, IIuy,~n: 86-93 Plate NO. 7 . 7 , 2- 3- 4- 5- 6' 7- 8' P lo- LP- BAG 1r 6 -SK I4 Etevrtlon 293.0 DESCRIPTIOll SM Brown very Silty Fine to Medium Sand With Many Chunks of Asphalt up to 18" and Concrete up to 4-5 feet. Minor Amounts of Wood (Sides Caving) (Fill) .------------ iron Silty Fine to Mediu and 'ragments of Clay Pipe, .arge Blocks of Concrete, ;ome Asphaltic Concrete md Wood - (Fill) ark Brown Clayey Silt (Colluvium) rownish Gray Fragmented iltstone & : m : :: ti a 1 Moist 10086 s-e oist . - - Bose rY ist dium iff rY ist ,d HEADQUARTERS EXPANSION PROJECT tihALq”AK’MKS EXi SUBSURFACE EXPLORATION LOG C.R.M.W.D. PROJ. No. 86-107 C.R.M.W.D. PROJ. No. 86-107 LoOOm BT: ".G. D4tC LOOOLD: l-,5&37 *, muyIEII: 86-93 Plate No. 8 : TRENCH NUMBER T-6 7 : *i; s;o : z 5 : f I- I s (Continued) u!! ;x- f :: L Elevation :: fY3 l a; I: 2% 293.0 ;g -- c :: SE z=; Uf 0. .I 3 2; 2 : 5 ..a :o’ .I g;‘; l -L 0’; : : I _. l a l 0= 2 ‘JO =:: 0’ =o =a u DESCRIPTIOR ; " 15 :: ML Brownish Gray Fragmented very Hard Siltstone Moist 16 1 Bottom of Trench Backhoe.Fully Extended 18 Excavated With Case 580 Backhoe - . CK=Chunk Samples BAGsLoose Bulk Sample HEADQUARTERS EXPANSION PROJECT SUBSURFACE EXPLORATION LOG C.R.M.W.D. PROJ. No. 86-107 LOOQCO ay:V.G. 01~s Loaoefxl-6-87 JO. WUYBI?~~: 86-93 Plate No. 8 (Cont.1 I Y 5 I f ; r ! a : 1' 2' CK 3- 4- 5- 6'- 7 8- 9- o-- I- z- 1 i’ :I I , IM z- L- - L - ~-- T&tiCkl HUHBER T-7 Elrv&n DEScRIPTIon lrown Silty Sand (Fill lellow Brown Sandy CJaye ;ilt (Fill)' )ark Brown Clayey Silt (Colluvium) 'ale Yellow Clayey Silt ;ray Siltstone With Lens ,t? Fine Sandstone and :ron Staining (Formation) Ittom of Trench :cavated With Case 580 xkhoe CK=Chunk Samples Moist ILoose Very i?aiG Moist Dense Ve?Zy Moist Very Moist Very Moist Stiff 3rd lut :agme. :ed ird :o !ry rd : f *: 0 I r! x i! ::: - - zt zz ‘0’ u HEADQUARTERS EXPANSION PROJECT SUBSURFACE EXPLORATION LOG C.R.M.W.D. PROJ. No. 86-107 LoaacD Dr: "eG- DATE LoOaiD: l-6-87 -, muyIgm: 86-93 Plate No. 9 -_ -- - - - - -- - - - - -, - - - - - 5 t 8 : f ; 2 8 0 1 l-r- 2- 3- 4- 5’ 6’ 7- 8-- P- lo- ll- lF- - z TiEtiCH NIMBER T-8 $ i fltvr~ion 0. 'f f 0 DESCRIPTIDN ML, Pale Yellow Clayey Silt (Fill) SM Dark Brown Silty Fine Sam With Large Chunks of Asphalt up to 2 feet (Fill) CL Brown Silty Clay (Colluvium) ML Pale Orange-Yellow Clayey Silt Mz, Yellow-Gray Siltstone Weathered and Fragmented :: :f a. t6 * 8 lery loist foist e=Y oist e=y oist S-=Y oist of 2nLtb [edium lense 80088 0 :edium ense tiff aft to odium tiff 3rd - - - HEADQUARTERS EXPANSION PROJECT SUBSURFACE EXPLORATION LOG C.R.M.W.D.PROJ. No. 86-107 LOQOCD BY: V.G. DAYC LC)OOCD: l-6-87 I JO1 MUYICR: 86-93‘ [Plate No. 10 - LABORATORY TEST RESULTS - -. - -. - - ..- - - Maximum Density/Optimum Moisture Sample No. Location Maximum Density (PCf) optimum Moisture (Percent) A T-l @ 2.0' 113.7 16.0 B T-l @ 5.5' 109.5 16.3 C T-2 @ 2.0' 116.5 14.8 Direct Shear* Sample Location Cohesion Angle of Internal Friction Number (PCf) (Degrees) A T-l @ 2.0' 740 11 *Sample remolded to 90% of maximum dry density at optimum moisture content, Samples saturated prior to testing. Expansion Test Percent Expansion Potential Expansion Index Expansion Sample No. Location Per UBC C T-2 @ 2.0' 14.4 144 Very High - WESTEl?N SO/l AND FOUNDATION ENGINEERING, INC. PLATE NUMBER 11 WESTE/?N SO/l AND FOUNDATION ENGINEERING, /NC. WESTERN SO/L AND FOUNDATION ENGINEERING, INC. -. l WQNL ,.exes3 4x3 HALE bMN”C . *Lltr CODE 810 ItscDNDIDO. cALIFMNI* msa2s - SF?RXFICATIONS ?OR CONSTWCTIoIl OP COWl’llOLLED FILLS -. CLNERAL DESCBIPTIOW: %e coertruction of controlled fillr l bell consist of adequate prelrminery roil invcrtigetionr, end clearing, removal of exirting l tructurem end foundetionr , preparerion of lend to be filled, cxcevation of earth end rock frw. cut area, compaction end control of the fill, end l ll other wrk neccrrery to complete the grading of the filled l rea to conform mth the loner, grader, end eloper l m ahown on the l ccepted plane. CLBARINC AND PBEPARATION OF ASEAS TO BE PILLED: Tel All fill control projectr ahell have e preliminery aoil inveotigetion or l via+ examination, depending upon the nature of the job, by l qualified roil engineer prior to grading. - _. ._. _. - (b) All timber, treea, brush, vegetation, end other rubbish rhell be removed, piled end burned, or otherwise disposed of to leeve the prepared l ree with l finirhed l ppcereocc free from unsightly debrir. (c) Any soft, wampy or otherwire unruiteble l rear, #hall be corrected by dreinege gr remove1 of comprerrible materiel, or both, to the depthr iodiceted on the plenr or es directed by the roil engineer. (d) The nature1 ground which ir determined to be retirfectory for the rupport of the filled ground rhell then be ploued or rcerified to l depth of et leert rix incher (6”) or deeper l a rpecified by the roil engineer, end until the eur- fete ir free from rut*, h\rmnocke, or other uneven feeturer which would tend to prevent uniform compaction by the equipment to be wed. (c) Uo fill l hell be pieced until the prepared native ground he@ been l pprwed by the roil engineer, (f) Nhere fillr are ude on the hillrider vith eloper greeter thee 5 (horizontell to 1 (verticel), borirontel bencher rhell be cut into firm undisturbed nature1 ground to prwide leterel end verticel rtability. The initial bench et the toe of tbe fill rhall be et leert 10 feet in width on firm undirturbcd natural ground et the elevation of the toe #take. The roil engineer #hell determine the vidth end frequency of rllnrcceeding benchcr which will very with the roil condition* md the rteeperr of elope. (g) After the neturel grouod her been prepered, it rhell be brought to the proper moirture content and cmpected to oot lerr then 90% of muilur denrity, A.S.T.U. Dl557-64T. -~ - - _- - (h) Expansive roils may require rpecial compaction rpecificrtions aa directed in the preliminary roil invertigation by the roil engineer. (i) The cut portion@ of building padr in which rock-like material exista mey require excrvation end recompaction for density canprtibility with the fill xa directed by the roil engineer. NATERLALS : The fill roilr shall coneirt of select materiels graded l o that at leaat 40 percent of the material p&area the No. 4 sieve. The material may be obtained frw the excavation, l borrow pit, or by mixing roils from one or more #ourcen. The material wed #hall be free fran vegetrble matter, end other del- eteriour rubrtancer, and rhall not contain rockr or lw~pe greater then 6 inches in diameter. If excessive vegetrtion, rockr, or l oile with unacceptable physical charecteristics l re encountered, these materiala Ihall be dirpored of in vaate area8 designated on the plans or l # directed by the roil engineer. If roil0 l re encountered during the grading operation vhich were not reported in the preliminary *oil investigation, further testing will be required to l rcertein their engineering propertier. Any rpeciel treatment recommended in the prelim- inary or subcequent roil reports not,cwered herein #hall become en addendum to these rpecificationr. No material of a perishable, spongy, or otherwise unstable nature rhsll be used in the fills. PLACING. SPREADING AND COMPACTING FILL-MATERIAL: ‘2e) The @elected fill materiel rhall be placed in layerr uhich #hall not exceed l ix incher (6”) when compected. Each layer shell be spread evenly cud rhall be thoroughly blede-mixed during the rpreading to ineuremiifonuity of materiil;and moisture in each layer. (b) When the moisture content of the fill material ie below that specified by the ooil engineer, wter @hall be added until the moisture content is oear optimum es determined by the roil engineer to eaaure thorough bonding during the can- patting procere. (c) When the moisture content of the fill material is above that specified by the coil engineer, the fill material shall be aerated by blading and scarifying, or other ratisfactory method@ until the moisture content is near optimum AS determined by the Ioils engineer. (d) After eech layer has been placed, mixed and rpreod evenly, it shall be thoroughly compacted to not less than the rpecified maximum density in accord- l nce with A.S.T.H. Dl557-64T. Compaction shall be by means of tamping or cheep*- foot rollers, multiple-vheel pneumatic-tired rollers, or other types of rollers. Rollers shell be of such design that they will be able to compact the fill to the rpecified density. Rolling of each layer shall be continuous over its entire srea and the roller shall make sufficient passes to obtain the desired density. The entire area to be filled shall be compacted to the specified density. WESTERN SOIL AND FOUNDATION ENGINEERING, INC. -2- -. - .,- - - - - _- - .- (e) ,lill rloper l bell be compectrd by weoe of rbccprfoot rollrrr or otbu l uiteble cquipmeut. Cmpectiog operetiooe l hell be cootioued until the elopes ue l teble but not too denre for pleotiog cod until there ir no l pprecieble m&t of loore roil oo the eloper. Campectiog of the l lopee l hell be l ccampliehed by beckrolliog the l lopee in iocrerotr of 5 to 5 feet in l levetieo seio or by other metbode produeiog l etiefectory rerultr. (f) yield deoeity tentm l hell be rde by the mail eogioeer for approximately l ech foot in l levetioo seio l fter compectioo, but oat to exceed two feet io vertieel beight betveeo temtm. The locetioo of the temtm in plan elm11 be #paced to give the beet poreible coverage end l hell be teken no farther then 100 feet epert. Tertr l hell be tekeo oo coroer eod terrece 100 for eech two feet in l levetioo gein. The roil l ogioeer mey t&e l dditiooel teetr u conridered neceeruy to check oo the uoiformity of compectioo. Mere l heepefoot rollerr UC wed, the teeta mhelr’be tekeo in the cwpmcted uteriel below the dirturbed rurfece. ,lso dditiooel Ieyerr of fill l hell be rpreed until the field deoeity tertr iodicete thet the rpecified density her been obtained. (0) The fill operetioo l hell be cootioued io rix inch (6”) compacted Ieyerr, em rpecified l bove, until the fill her been brought to the fioiihed eloper cod greder l e l bouo oo tbe l ccepted pleor. mPERvIsIoN: Supervirioo by the coil eogioeer l hell be mede during the filliog cod campectiog operetiooe eo that he ceo certify that the fill vea made in ucord- eoce 6th l ccepted rpecificetioom. The rpecificetioor sod roil tertiog of rubprede, subbeee, md beee meterielr for roede, or other public property l hell be done in l ccordeoce with l pecificetiooe of the govecoiog l geocy. BE&SOUL LIMITS: Uo fill uteriel l hell be pieced, rprcad, or rolled during uufevoreble weether cooditiooe. Theo the uork ir interrupted by hemy rein, grediog l hell oot be rerumd uotil field temta by the roil l ogioeer iodicete thet the moirture cooteot cod deority of the fill l re l e previourly rpecified. Io the eveot thet, in the opioioo of the-engineer, l oile ooeetirfectory l e foundetioo uteriel ue l ocouotered, they #hell oot be incorporated io the grediog end dieporitioo vi11 be aede et the eogioeer’e dircretioo. WESTERN SO/L AND FOUNDATlON ENGINEERING, INC. -E