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HomeMy WebLinkAboutCT 76-15; Palisades Point; Soils Report; 1983-06-30ENGINEERING June 30, 1983 W.O. 386901 Mola Development 808 Adams Avenue Huntington Beach, California 92648 Subject: Preliminary Soils Engineering Investigation Tract No. 76-15 Palisades Point Carlsbad, California Gentlemen: Pursuant to your request, a Preliminary Soils Engineering Investigation was performed at the subject site. The purpose of the investigation was to determine the general engineering characteristics of the soils and bedrock materials on and underlying the site and to provide specific recommendations for the design of foundations and under- ground improvements. It is proposed to develop the site with 139 residential lots to be occupied by one and two-story wood frame structures constructed over slab on grade. The structural loads are not known at this time, but for the purpose of this report, they are assumed at the twenty (20) kip range for column loads and wall loads in the range of three (3) kips per lineal foot. Grading will be comprised of a cut and fill operation. Maximum thickness of fill will be on the order of fifty~ (50') feet. cut slopes will be up to sixty-fives (65i') feet high at a ratio of 1.5:1 (horizontal~:vertical) and fifty (50&I) feet high at 2:l. Fill slopes will be up to forty-seven (47i') feet high at a ratio of 1.5:1 and sixty (60') feet high at 2:l. 16306 South Sunk&t St.. Anaheim. Ca. 92806 (213) 652.4710 (714) 634-2092 Mola Development Page 2 W.O. 386901 SITE CONDITIONS The subject site is a vacant forty-eight (48) acre parcel of gently rolling terrain forming the east flank of a northwest trending ridge- line. Its is bound on the east by El Camino Real and existing condo- minium units, and on the north, west and south by vacant land and existing residences. Elevations within the site range from a high of 330* feet along the southwest property line to a low of 120f feet along El Camino Real producing a relief of some 210 feet. Vegetation consists of dry grass and brush and scattered small trees. FILL CONDITIONS Fill materials were encountered as described in the attached Geological Reprjrt and illustrated on the Geological Map. These materials are considered to be moderately compact at best. NATURAL CONDITIONS Natural earth materials present consist of residual soils, alluvium, terrace deposits and sedimentary bedrock. Residual soils and alluvium consist of clayey SANDS and sandy CLAYS. Terrace deposits care composed of firm, RED/BROWN, silty SANDS with occasional lenses of GRAVEL and CLAY SAND. The sedimentary bedrock is made up of two (2) units: (1) a firm, GREY/WRITE, silty and clayey SANDSTONE with (2) interbeds and lenses of GREY/GREEN silty CLAY. - Additional details ,concerning the natural earth materials are presented in the accompanying Geological Report. FIELD INVESTIGATION A field investigation was performed from May 25,-1983~ through,June 7, 1983, consisting of the excavation of fifteen (15) test pits and 1630-G South Sunkist Street Anaheim, California 92606 (714) 634-2092 (213) 652-4710 Mola Development Page 3 W.O. 386901 borings by backhoe and bucket auger drilling equipment at locations shown on the attached plan. As the test borings were advanced, the soils were visually classified by the Field Engineer. A summary of the borings is attached. Undisturbed samples for detailed testing in our laboratory were obtained by pushing or driving a sampling spoon into the material. A solid barrel-type spoon was used having an inside diameter of 2.50 inches with a tapered cutting tip at the lower end and a ball valve at the upper end. The barrel is lined with thin brass rings, each one (1") inch in length. The spoon penetrated into the soil below the depth of boring approximately twelve (12") inches. The central portion of this sample was retained for testing. All samples in their natural field condition were sealed in air-tight containers and transported to the laboratory. LABORATORY TESTING Shear tests were made with a direct shear machine of the strain control type in which the rate of strain is 0.05 inches per minute. The machine is so designed that tests may be performed ensuring a minimum of distur- bance from the field conditions. Saturated specimens were subjected to shear under various normal loads. The results of tests, based on ultimate residual values, are tabulated below: Boring Depth in Cohesion Angle of Internal No. Feet Material Lbs./Sq. Ft. Friction (Degrees) B-l B-3 TP-3 .~ TP-2 TP-4 - TP-6 TP-7 44.5 Sandstone 300 35 26:5 Sandstone 1100 35" 1110 Claystone** 150 10 (initial shear). 150 20 Silty Sandstone 250 :: ~210 Sandstone Lo: 39 310 Terrace Deposit 150 33 . ., 4.0 .Clayey Sand*** 122 400 j 3 TP-9 5.0 Sandy Clay 27 250 s :i 1630-G South Sunkist Street Anaheim, California 92806 (714) 634-2092 (213) 852-4710 Mola Development Page 4 W.O. 386901 - , Test results by Woodward-Gizienski h Associates (1973): Sandstone 300 ' 35 Claystone 600 1 25 Compacted Fill 450/ 27 *Test performed at field moisture **Re-molded to field density and re-sheared three times ***Re-molded to approximately 90% of maximum density Consolidation tests were performed on in-situ moisture and saturated specimens of typical soils. The consolidometer, like the direct shear machine, is designed to receive the specimens in the field condition. Porous stones, placed at the top of the specimens, permit the free flow of water into or from the specimens during the test. Successive load increments were applied to the top of the specimen and progressive and final load settlements under each increment were recorded to an accuracy of 0.0001 inch. The final settlements so obtained are plotted to determine the curve~s shown in Appendix C. Expansion tests were performed on typical specimens of natural soils. These tests were performed in accordance with the procedures outlined in U.B.C. Standard 29L2. Results of these tests are presented in Table II and indicate the soil and bedrock materials exhibit expansion potentials ranging from very high to low, with higher values corres- ponding to claystone bedrock and lower values to sandstone bedrock. CONCLUSIONS AND RECOMMENDATIONS - On the basis of our investigation, development of the site as proposed ': is considered feasible from,.a soils engineering standpoint provided that the recommendations stated herein are incorporated into the design of the grading plan and foundation systems and are implemented in the field. Existing trees, low vegetation and old irrigation systems shall be stripped and removed from the site. 1630-G South Sunkist Street Anaheim, California 92606 (714) 634-2092 (213) 652-4710 Mola Development Page 5 W.O. 386901 The entire grading operation shall be done in accordance with the attached "Specifications for Grading." All loose alluvial and fill material shall be removed from the proposed fill areas. The bottoms of all excavations shall be inspected by the Project Soil Engineer and Geologist prior to the placement of any fill. Any import fill material to the site shall not have an expansion index greater than twenty (20), and shall be tested by our laboratory. All grading and/or foundation plans shall be reviewed by the Soil Engineer. SLOPE STABILITY Based on the stability analyses contained in Appendix A, the following maximum slope heights are recommended: Material Slope Ratio Maximum Height Surficial Stability Fill Slope 1.5:1 35 ok Cut Slopes ,:: Terrace Deposits Sandstone 2:l 60 ok 1.5:l 30 Low 2:l 65 Low l-5:1 65 ok 2:l 65 ok Claystone 1.5:1 10 Low 2:l 15 Low I: Surficial stability conditions should be re-evaluated at the time of grading, since loose sands or clay in cut slopes could degrade stability, ~: and fill slopes composed primarily of sand will likely be subject to surficial erosion. Slopes exhibiting low surficial stability should be planted as soon as grading is completed, and it may be prudent to consider the use of 1630-G South Sunk&t Street Anaheim, California 92806 (714).634-2092 Mola Development Page 6 W.O. 386901 hydromulchorother means to encourage plant growth and retard slope erosion. The above slope heights have been determined for the maximum heights proposed by the current grading plan , ,and where these slopes exceed a factor of safety of 1.5 and 1.1 for static and pseudostatic cases, respectively, lower slope heights are indicated. Local geologic structure, and the presence of claystone bodies in cuts, may require stabilization; such measures shall be evaluated at the time of . grading. On the basis of the Geologist's report and stability calculations, it has been determined that the proposed 1.5:1 sixty-five (65*') foot high buttress/cut slope at the rear of Lots 100 through 109 does not exhibit a suitable factor of safety against deep seated failure. This slope should be constructed at a ratio of 2:l or flatter. A retaining or crib wall may be used at the toe of the slope, in order to prevent reduction in lot sizes. Plans for any such retaining structures should be reviewed by this office prior to construction. Proposed fill slopes over thirty-five (35') feet in height should be flattened from 1.5:1 to 2:l. Additional recommendations regarding slope stability are contained inkhe attached Geological Report. FOUNDATIONS The proposed structures shall be supported by isolated and continuous spread footings placed a minimum depth of twelve (12") inches below -.- lowest adjacent finish grade utilizing a recommended safe bearing value of 2600 pounds per square foot and 2100 pounds per square foot', respect- ively. This value is for dead plus live load and may be increased by one-third (l/3) for total including seismic and wind loads where allowed by code. Increases in bearing capacity for increases in footing dimensions are tabulated below: 1630-G South Sunkist Street Anaheim, California 92606 (714) 634-2092 Mola Development Page 7 Minimum IYF!s Depth (inches) W.O. 386901 Continuous 12 12 2100 314 109 4100 Isolated 12 12 2600 314 105 4100 Minimum Width (inches) Bearing Value Maximum Depth Width (psf) (psf ft)(psf/ft) Due to varying expansive conditions, minimum embedments will vary in accordance with the attached "Expansive Soil Recommendations." Footings which span from native material to compacted fill shall be reinforced.with a minimum of one (1) #5 bar top and bottom to control potential differential movement. Reinforcing bars shall extend a minimum of ten (10') feet on either side of transition line. Footings placed on or adjacent to slopes shall.have a minimum horizontal distance of five (5') feet from the edge of the footings to the face of the slope. LATERAL DESIGN Lateral restraint at the base of footings and on slabs may be assumed to be the product of the dead load and a coefficient of friction of 0.35. Passive pressure on the face of footings may also be used to resist lateral forces. A passive pressure of zero at the surface of finished grade, increasing at the rate of 240 pounds per square foot of depth to a maximum value of 2400 pounds per square foot may be used for natural soil and compacted fill at this site. If passive pressure and friction are combined when evaluating the lateral resistance, the value of the passive pressure should be limited to two-thirds (2/3) of the values given above. EXPANSIVE SOILS - Results of expansion tests indicate that the near surface soils have a very low to very'high expansion potential (refer to Table I). Expansive soil recommendations in ApPendix.C shall:be.con$idered fin design of foundations and slabs for buildings lying within the respective soil types. A lot by lot testing at the completion of grading will be made to determine the expansion potential. 1630-G South Sunkist Street Anaheim, California 92806 (714) 634-2092 (213) 852-4710 Mola Development Page 8 W.O. 386901 Positive drainage away from the foundations shall be maintained. CUT/FILL LOTS On pads where a transition from cut to fill occurs within the planned building area, the natural material should be undercut to, a depth of thirty (30") inches below finished grade and replaced as compacted fill to develop a more uniform condition of support for the buildings affected. This requirement may be waived at the discretion of the Soil Engineer if field tests show the natural material to be satis- factorily compacted ~(85% minimum relative compaction) within the specified depth. After completing the undercut, the exposed surface material should be scarified to a minimum depth of six (6") inches, brought to approximate optimum moisture content and compacted to at least ninety (90%) percent of maximum density in preparation to receive fill. As an alternative to undercutting transition pads, it would be acceptable to deepen footings in shallow fill areas so that the entire foundation system would rest on natural material. GRADING REQUIREMENTS It is recommended that site grading be carried out in accordance with the "Specifications for Grading" in Appendex B. Additional requirements may be recormnended by the Soil Engineer in the course of work, depending upon conditions exposed during grading. SETTLEMENT The maximum anticipated total settlement is on the order of done-half (l/2") inch. Differential settlements are expected to be'less than one-fourth (l/4) inch, measured between adjacentstructural elements. * SUBSIDENCE AND SHRINKAGE 4 Subsidence over the site is anticipated to be on the order of 0.20 feet. Shrinkage of reworked materials should be in the~range of fifteen (15%) percent. 1630-G South Sunkist Street Anaheim, California 92806 (714) 634-2092 Mola Development Page 9 W.O. 386901 PAVEMENT STRUCTURAL SECTIONS Representative samples of subgrade materials should be obtained after the roadways have been rough-graded and tested to establish R-values for use in calculating suitable pavement structural sections for the various areas. UTILITY LINE BACKFILLS It is recommended that backfills placed below and within five (5') feet of buildings, below asphalt concrete pavement and portland cement concrete flatwork, and within ten (10') feet of any slope, be compacted to at least ninety (90%) percent of maximum density. Backfills placed in other areas to be landscaped need only to be compacted to eighty-five (85%) percent of maximum density. All backfills require testing at two (2') foot vertical intervals during placement. On-site sandy materials are considered excellent for use in utility line backfills; however, finer-grained materials may be difficult to compact. As an alternative to compacting the backfills, trenches could be backfilled with a sand-cement slurry containing at least five (5%) percent cement per cubic yard. In this case, field density testing will be waived by this office; however, batch plant tickets and periodic inspection during placement may be required. If the slurry method is selected, eighteen (18") inches of compacted, fine-grained site material should be provided in areas to be landscaped to minimize water infiltration and to promote plant growth. CAVING Caving did not occur in any of the borings drilled for this investigation and is not expected to be of significant concernduring grading and construction operations. The regulations of Cal/OSHA should be observed during performance of all work. FLOOR SLABS Slabs on grade should be designed according to recommendations for medium expansive conditions, as shown in Appendix.C. r_Care should-be 1630-G South Sunkist Street Anaheim, California 92806 (714) 634-2092 (213) 852-4710 Mola Development Page 10 W.O. 386901 exercised to ensure that reinforcing mesh is placed in the center of the slab. The soil should be kept moist prior to casting the slab. However, if the soils at grade become disturbed during construction, they should be brought to approximately optimum moisture content and be rolled to a firm, unyielding condition prior to placing concrete. In areas where a moisture sensitive floorcovering will be used, a vapor barrier consisting of a plastic film (6 mil polyvinyl chloride or equivalent) should be used. Since the vapor barrier will prevent moisture from draining from fresh concrete, a better concrete finish can usually be obtained if at least two (2") inches of sand is spread over the vapor barrier prior to placement of concrete. IN-GRADING TESTING AND INSPECTION Periodic site inspections by our Soil Engineer and/or Geologist during grading and foundation construction will be necessary to verify the soil and geological conditions encountered during the course of this investigation. Further recommendations may be required if conditions other than anticipated are encountered. In addition, continuous testing during placement of fill will be necessary in order to verify that adequate compaction is being achieved. GENERAL INFORMATION This report presents recommendations pertaining to the subject site based on the assumption that the subsurface conditions do not deviate appreciably from those disclosed by our exploratory excavations. Our recommendations are based on the technical information gathered, our understanding of the proposed construction, and our experience in the geotechnical field. We do not guarantee the performance of the project, only that our engineering work and judgements meet the standard of care of our ~profession at this time. In view of the general conditions in the area, the possibility of i different local soil conditions cannot be discounted. Any deviations 1630-G South Sunkist Street Anaheim, California 92806 (714) 634-2092 Mola Development Page 11 W.O. 386901 or unexpected conditions observed during construction should be brought to the attention ofthe Geotechnical Engineer. In this way, any required supplemental recommendations can be made with a minimum of delay to the project. If the proposed construction will differ from our present understanding of the project, the existing information and possibly new factors may have to be evaluated. Any design changes and the finished plans should be reviewed by the Geotechnical Consultant. Of particular importance would be extending development to new areas, changes in structural loading conditions, postponed development for more than a year, or changes in ownership. This report is issued with the understanding that it is the respon- sibility of the owner, or of his representative, to ensure that the information and recommendations contained here are called to the attention of the Architects and Engineers for the project and incor- porated into the plans and that the necessary steps are taken to see that the Contractors and Subcontractors carry out such recommendations in the field. This report is subject to review by the controlling authorities for this project. We appreciate this opportunity to be of service~to you. Respectfully submitted: ACTION ENGINEERING CONSULTANTS &PP& BRUCE A. PACKARD RCE 13801 VICE PRESIDENT - ENGINEERING Gw:RA:ss -GEOLOGIST STAFF ENGINEER ‘4, j 1630-G South Sunkist Street Anaheim, California 92806 (714) 634-2092 Mola Development W.O. 386901 APPENDIX A Slope Stability Calculations ‘- 1630-G South Sunkist Street Anaheim, California 92806 (714) 634-2092 SLOPE STAB/L/T,Y : fg to / .SLOR3- GEOMETHC DATA f I ,627 I -2zo I x.5 I 495 . ‘ I , SLICE CHQ9D # ANGLE e'C 22 z5 19.0 31.0 .4 8.0 - . -id&r.,) ._ 5 s 4.o ,625 22.5 .56.0 - lZ.7 -35 l0.b 24.3 .E NUMBER +k f b.CU?S D.0775 CIOBN a0363 0. l/lJ 0.1425 0.1325 3 0.0588 .D.lSB _ ml75 . a?350 ^ 4 0.0800 0.2m5 03088 0.3700 ., .‘. ~~_ .~ _~ .‘~ .. .~ . i 1 t J :j t i 1 1 (I , . -5 <: $ .T SLOPE S7ZWffTY ANALEX . . 192 lo / ,SL OPE RAT/O - Cl,’ .’ ff= 35 55ET . & D./h KCF . . .,,&= .fN-t+ ~:; ; QA?.c+~FN Yu~+ T ,. -.c= 0;400’ KS?= ]. & 22, Jjwees’ .;: -7AN &. 0; 464’ ’ ., ‘1 _.. 1.. _~~ ,1 SLOPE S7’XBUi~Y ANALYSIS . ’ 19~ to / SLOPE RAT/O - c,f, ?&me by**+ : so ‘EET, . ;: 0.126 KCf RSEUDOSTAZ’C~ MODlFlCA?-,lON : ..Fj= F..+pG SfR =,&C+zfN ~tm$ ~~ ~j,= .&‘t7Fj :; : ‘-c= d*/SO. USF 1, )’ ;.. : :-‘,@ ~5 33 ‘Deprees ‘~ ,.sd.l g _. .7AN $& 0.65” .~ .: .,~ A sind 1 SLlCE - ,-fdXH’= ---.----- -- 3 . Fj/tyffZ= A Cosd i!CLE * , If.?!TL t- =2 C.‘KL r 43 C!RCLC &4 ‘A 0.0087 .Q0054 .-.004/ --.024/ 0.0313 00409 0.0587 010763 _ --O/33 B 0.0352 0.0362 O.O233 0. mgl _ o/o52 O.f55R O2/7/ 1 Pa \ 0.0495 0.0734 lo-0852 0.0536 .& 00645 0.1221 02009 0.3041 .D 0.0276 0.0985 0./38/ 0.1534 0.0236 OOt?87 O/90/ 03367 I-. ,;f,, - 0.0844 0. f944 - 0.0625 012236 .F - 7 : O.0860 - - 0.0487 ,Zf&tfz] O/2/0 : IO.2135 ,0.3249 '(0.4490 -Z~;/l”‘]lO/885 ] 03569 j06660 (I.2065 . em_ -_ ‘1. .~LWfE sT;QE)IttTY AAfAf ?fSf.S ‘. . . /!44 I'o I SLOPE RAT/O - .U,J’an-&fon~ .~ .._. psNDoSTAT/C MOD/F/CAT~~N f 2Ef& =sc+=ffl .fUR# ., ,.‘.fNy.fN-afT :~ : :’ .:;~ ’ . . ~ -;:,,c 3 ,.300 .KS f ~’ .‘I ’ -: I :#‘s .&Degees ; ~. ., *.-f d/ g : TAN j,$t~ ~di700’ ; 1 . . .: 0.0495 0.0734 0.0832 0.0536 00645 O.J2.?J o.a?oog 0.304J 110.0.??6 ~~ogtYs oJ381 10./534 . - 110.0276 b.0985 1OJ381 10./534 J (IO.0236 100&?7 ho/ !o.z - L ~Z 10.0844 : f 11 --- 1 - , .--~. - 1 ,>-T;; ,l - z~~j/ &HZ O-J210 . jO.ZJ33 jO.3249 M4Y” .~ ,, ,zFN-,/&‘]j 0. J665 1~3569 70.6680 1 J-2065 r/G IN,Ksl II 6’1.3 1 /d&2. .I ~227*t% , --.-- -. xFN /x&=s~ 11 9&G, 6 1 /LA 9 “I A-..~‘. . . _ :.. _ ~., ..z.. . ..-. _ -.,-. :~ .~ ,. :_ - ,-.L LA ‘i ;; ‘.: .~ .- ~. ,,I. <.;.,;-,, -_ ,~ _:’ ,. -:: ..~ ..i: _ ~, .SfOPE SZ.I./L/TY ANA~~SB . ’ /pz to / SLOPES RAT/Q - ti, ~c’o~~fo~e ff= /o EET f?SEUDOSTATlC‘~ MOD/F/CAT/ON & d//zb KCF ffl= fT+ ff f,, ri’A = LC+=fN tffn$ ., -,~f,*= .fN-fffT I d;/50 .KSf 1, “mf ~~ ., 2o &Tees ~: ‘JAfl &= 0.4m. 03569 Ct66BO J.2065 =frmfKMSJ 1~5 2#L rf# <K/I%) 2.3 e3 _ -. ., 1: _. ; ._.,.. ~._.L . .._ ~~-~ _ _ ‘~ . . ., i, ‘- ,,.~, .- -i- .* -. ,. ,.~~.._ ~. _...,. . . ..~ .! i . . i ,~ ;f ! 9 i :f i ,I i a : 1 i i I SLOPE STALVLITY 2 to / SLOPZS-GEOiUETiVC -DATA .38.5, - ,+?8.0 .: ..~:&5e3 1 L :i. --. ~.. :’ ~,~,75 r:; ‘.:‘3Jo ‘~~ -:Jp.o “.- ‘~: I-.;’ 5.0 .. Z37.0 3ZO S85 0.0760 . .- - -‘. .. c).1775 ‘S. if94 i- 0.3050 ~03lDO ZlNBO 7 0.4638 0.5325 0.458 8 0.1838 . Sf OPE SirAB/L/TY ANALKXS 2, to / SL OPE RAT/O -~ K/l ,‘H= LO’ m P!.EUDL~STA?~C A40D1'RCm~ofl & h/z0 KCf f;a=,FT+ ifN .zLfR=Lc+xF~ mi # F’j’= FN -~f-~ I SL/CE ! .~ /;CXH’= .A sjnti -f,/~~~~~~o~~-‘y--- CfRCL E * I CIRCLE r.? tl.%.LE =3 ~24 0.0072 O.Oi20 --.0/6.7 0.0368. 0.0600 0.0859 B ‘~’ 0.0342 00363 0.0139, 0.0805 0.14 55 0.2271 c_ 0.0473 0.0833 0.0917 0.0595 0.1567 02909 .D -. .- 0.0852 0.1688 0.0837 0.2600 ClRCL E ‘=l -. 0518 0. t//o -.~0573 0.3250 .0.0404 0.4620 0. /821 0~ 5034 .f 1 = 0./087~ 0.2761 0.0850 0.3664 .F ‘, - - - .’ . OJ567 ; - - t jX.fj/d,yp 110.0887 IO.2068 IO.3664 ZF/;;/buP 0.7762 0.4459 0.9489 t. 8608 t fi WPS) 38.3 sr.3 csf.3 236.0 YO%9 SOT,.9 .:__: ..z_, ,.~_ Z..1.~ ._ i,l 2 ‘~-y:--.y I ,~. : ‘. i 1 . . :r ; i .: z : .: 1 -s ; ‘; ,: Sf OPE STAB/L/TY ANALKXS 2. to / SL OPE .’ RATIO - co< ,&-& &pa,+ & & .$= ‘*;,zo PSEUDOS TA7-X MOD~~CAT/ON KCf fig --.Fid AFN I-fR=&+=fN lOti + .’ fN’= FN -0Fj = d,.60 KSF ~; I, 33 ;Desrees .7=&g .’ -~rdN #= (j#&S .,~ -‘/RCL E * I CIRCL E *.? ,%QcL E -3 CIRCLE “4 A 0.0072 0.0020 --O/67 -. 0518 0.0368. 0.0600 0.0859 O.///O 0.0342 00363 0.0139~ -.0573 0.0805 0./455 0.2271 0.3250 II ClffCL E * I CIRCLE *.? CMCL E -3 CIRCLE “4 0020 -. O/67 -. 0518 ,, Y.UJPO. , ~0600 0.0859 O.///O 0363 0.0139~ -.0573 ,, v. VOUJ , u/455 0.2271 0.3250 c. 0.0473 0.0833 0.0917 .0.0404 .. 0.0595 0./567 02909 0.4S20 .B 0.0852 0.1688 0.182/ - 0.0837 0.2600 0.5034 .f: = 1 0.1087. 0.2761 0.0850 0.3664 - -. O-/567 - 0.0960 #X7/&f?= 0.0887 0.2068 0.3664 0.5462 Sf OPE STAB/L/TY ANALYS/S .2, jo / ~.SLOPE RATIO C&t’, &-‘&e H= -5-d & PSEUDOSTA7i'C MODiffCA7/ON - 1(= it;/20 iCF F--e =, F7+ oFN xFR=Lc+=fN fh 4 fN*= fN -fffT CT 6’~=0 KSf ,, $JJ =.. ;.y Pegrees n~=DI/g. ~-7dN # = 0,700 I ,“_. -- ,. ‘: ,; .-.e. ,;,, , f.:.~’ .:. ; 1 : : -I‘.~, .: ., I _, ., ,~ ,..._.-. ~~ .~ y;-I_-- ‘- -: _--_ :l_L.i, - ~.. . ,? _ ,.., . ..Z..~. ._:i,. :.~ _ ~~...~. : ,;. :. 4 Sf ICE : t=/#H.? s 1 Fu tKll?T) I+* tK1PS.l %” <KlPS) 1 Fj-LXH’= .A sjnti --- ------------ fN/JH2= Acooscx .. CIRCLE * I CIRCLE ‘=2 tJ.VZL E =.3 CIRCLE =4 0.0072 0.01920 --O/6.7 -. 0518 / 0.0368. 0.0600 0.0859 O./i/O 0.0342 00363 0.0139, -.0573 0.0805 OJ455 0.227/ 0.3250 0.0473 0.0833 0.09f 7 .0.0404 0.0595 O-/567 02909 0.4620 - 0.0852 0./688 O-/82/ - 0.0837 0.2600 0.5034 - - 0. iO87, 0.2761 - - 0.0850 0.3664 - -.‘, 0.1567. - - - 0.0960 _ 0.0887 0.2068 0.3664 IO.5462 3.7762 IO.4 459’ IO.9489 1 i. 8608 X.6 1 62.6 i /0%9 1 163.4 SLOPE STALVLITY ANALKSXS 2, to / SLOPE RAT/O ~9, f/bydk 6 m .;=y PSEUDOS.TA77C MOD,!ffCA7/ON O#iZO KCF ‘, oft.= FT-b & xfj? =&+=fN h (d .fN’=fN -of7 = di/so KSf . .j,,^~. . __~ ‘. - _ . “. ,.’ :..*\, ~.. ;.; ., !.< -.. ~.,._ ._ -,.L..-:: . . . ,. . .- __ __.-. .~_.._ : ..~~. ,. .~,~ t- -.~- .._ -.--.~- _ ~.~,.~ I -,L.. ‘. ~’ :E .-t fff.1 ~. 1 F, Yk7PS i! :: , .: _ .j’, +: ’ ._ ; I SlJRFlCIAL SLOPE STABILYTY /5.‘/ S/,,,J . . . Path Saturation ~To FailYrb Path Sufficient Permeability To Establish Water Flow Pw = Water Pressure Head u- Pore Water Pressure ~4~s -.Saturated.Soil Unit Weight ,. > .-?JY - Unit Weight of Soil.Water ,, .'~. ,, . ~~=k?CtoS?#c ~' 'a - w*G? tos2& . 3 f* ~= Ai!(wI-w" ) ~ ~ 'f,S.- 21 (Ws -W, ) cos2& tan 6 + 2 F +F sin 2cC (2$(4)(/2&l-L?) eos’ 34 760 35 + 2(300) &clg#one~ = m3 (4) -= 854 474 /.8 sic, 68 o,< CA-ys&e : (2 lf4)f/zg- 62) cas~34 A2m 20 + 2hO3 432 :.- = cl?/ &, /3g (4) sir L8 474 ..~ .~~, (I )(4K/28 -i2) cosp 34 & 22 -+ 2l9ao) 947 .c// ** .., ~_ /?B (43 s;cr tiq = - = 2.0 O.K. 474 ‘JURFICIAL SLOPE STABILYTY s?:/ %,,Qs . Slope Surface- ,zines ’ .’ Path Saturation'To Failore Path Sufficient Permeability To Establish water Flow P' = Water .Pressure'Head u- Pore Water Pressure ~~4s =.Saturated.Soil Unit Weight z.. :,+.-Unit Weight of Soil Water ..&# ~--a? cask al - W&i? cos24c 2’; 2:; 3 ‘yJ.~..a; d ; + : I --w, ‘~ f.S.= 23 (ws -w,) cos20c tan pl+ 2 C +? sin 2rC %d97&7e I (2 )(4)(/&?8-62) Em226 -ke 35 f 2/3&j) (4)4&J = 899 4P 52 -,- 403 2.2 .; ox. ,j C/a Q)f4)(/2&&!) cd~6 67 20 * 2fi50) 3f0l7e = >' 7 ,,,;. "~ /z/4) A& 52 ~~. ~-~I = ~~;:/#//J 4 IT/L: (2’)14 )(l537& ).cm2.&i 7$+‘5”~t -d460)'=' 972 1. '~ -= 34 . -. ,:. !?B~.(P 1 ai;, 52 .,i :R,~. 403 .:,~~.d,k: Mola Development W.O. 386901 APPENDIX B GRADING SPECIFICATIONS 1630-G South Sunkist Street Anaheim, California 92606 (714) 634-2092 (213) 652-4710 SPECIFICATIONS FOR GRADING SITE CLEARING The existing loose fill soils (see Logs of Boring for Depth) shall be excavated to competent native ground. Prior to the placement of any fill soils, the exposed surface shall be scarified, cleansed of debris and recompacted to 90% of the Laboratory Standard under the direction of the Soils Engineer in accordance with the following "Specifications for Compacted Fill". PREPARATION After the foundation for the fill has been cleared, plowed or scarified, it shall be disced or bladed until it is uniform and free from large clods, brought to a proper moisture content and compacted to not less than 90% of the maximum dry density in accordance with ASTM:D-1557-70 (5 layers - 25 blows per layer; 10 lb. hammer - 18 inch drop; 4 inch diameter mold). MATERIALS On-site materials may be used for the fill if cleansed of debris, or fill materials shall consist of materials approved by the Soils Engineer and may be obtained from any other approved source. The materials used should be free of vegetable matter and other deleterious substances and shall not contain rocks or lumps greater than six (6) inches in maximum dimension. PLACING, SPREADING AND COMPACTING FILL MATERIALS A. Is. C. The selected fill materials shall be placed in layers which, when compacted, shall not exceed six (6) inches in thickness. Each layer shall be spread evenly and shall be thoroughly mixed during the spreading to ensure uniformity of material and moisture of each layer. Where the moisture content of the fill material is below the limits specified by the Soils Engineer, water shall be added until the moisture content is as required to assure thorough bonding and compaction. Where the moisture content of the fill material is above the _. , ^ _ limits specified by the Soils Engineer, the fill materials shall be aerated by blading or other satisfactory methods until the moisture content is as specified. D. After each layer has been placed, mixed and spread evenly, it shall be thoroughly compacted to not less than 90% of the maximum dry density in accordance with ASTM:D-1557-70 (5 layers, 25 blows per layer; 4 inch diameter meld; 10 lb. hammer - 18 inch drop) or other density tests which will attain equivalent results. Compaction shall be by sheepsfoot roller, multi-wheel pneumatic tire roller or other types of acceptable rollers. Rollers shall be of such design that they will be able to compact the fill material to the specified density. Rolling shall be accomplished while the fill material is at the specified moisture content. Rolling of each layer shall be continuous over its entire area and the roller shall make sufficient trips to ensure that the desired density has been obtained. The final surface of the lot areas to receive slabs-on-grade should be rolled to a dense smooth surface. E. Field density tests shall be made by the Soils Engineer of the compaction of each layer of fill. Density tests shall be made at intervals not to exceed two (2) feet of fill height provided all layers are tested. Where the sheepsfoot rollers are used, the soil may be disturbed to a depth of several inches and density readings shall be taken in the compacted material below the disturbed surface. When these readings indicate the density of any fill or portion thereof is below the required 90% density, the particular layer or portion shall be reworked until the required density has been obtained. F. The grading specifications should be a part of the project specifications. G. The Soils Engineer shall review the grading plan prior to grading. INSPECTION The Soils Engineer shall provide supervision of the site clearing and grading operation so that he can verify that the grading was done in accordance with the accepted plans and specifications. -2- ~. < SEASONAL LIMITATIONS No fill material shall be placed, spread or rolled during unfavorable weather conditions. When work is interrupted by heavy rains, fill operations shall not be resumed until the field tests by the Soils Engineer indicate the moisture content and density of the fill are as previously specified. -3- Mola Development W.O. 386901 APPENDIX C Foundation Criteria, Expansion and Consolidation Test Results 1630-G South Sunkist Street Anaheim, California 92606 (714) 634-2092 (213) 652-4710 EXPANSIVE SOIL RECOMMENDATIONS W.O. Expansion Index Very Low O-20 LOW 2!-50 Medium 51-90 m 91-130 z_ Footing Width I '1 story II See Body I 2 story of Report ii:: I 12” I 12” 15" 15" Exterior Footing Oept See Body of Report ]2”.. 18” 18” 18” 18” _ 18” f I 12” 12” 12” 18” 12” 12” 18” 18” I "ooting Reinforcement Not Required 2 #4 bars 2 #5 bars 4 #4 bars ' 1 top 1 top 2 top 1 top 1 bottom 2 bottom _.-_ --- Slab Thickness 4” Nom, 4” Nom. 4” Nom. 4" Actual 'lab Reinforcement Not required 6 ” x6 ” 6”xb” #3 bars on 18" #lO/iilO #6/#6 . center both way Moisture Barrier (2) 6 mil visqueen 6 mil 6 mil 6 mil 1” sand visqueen 1” visqueen 1” visqueen 1" sand sand sand - Garage Reinforcement Grade Beam - Garage Entrance I 6”x6” #lQ/#lO 4 No; ;;z;ireBd or l/4 slab 1 Fgl;;exeg,,Floating FB;lexeg,,Floating I/ 1 (3) #lO/#lO #6/#6 Not Required Not Required Same as adj. Same as adj. ext. footing ext. footing * Subgrade Presaturation Not Required Not Required 4” coarse 4” ‘coarse sand (4) sand (4) 1, [ Not Required Above opt. m/c 110% of optimum 120% of optimum to depth of footing (No ;;;t;;gdepth of n/c fo depth of testing) footing Note: (1) (2) (3) (4) The surrounding areas sould be graded so as to ensure drainage away from the building. Concrete floor slab in areas to be covered with moisture sensitive coverings shall be constructed over a 6 mil plastic membrane. Properly lapped, sealed and protected with sand. The plastic should be Quartering of slab should be accomplished by.the use of pre-molded expansion joint material and not by saw cutting. One (1") inch of sand over moisture barrier may be included in this four (4") inch total. A- ACTION Mola Development W-0. 386901 TABLE I Test Pit Depth in Expansion Expansion No. Feet Material Index ~Potential 1 3 2 3 3 11 7 4 '9 5 Terrace Deposit 0 Very Low Sandstone 4 Very Low Claystone 165 Very High Existing Fill 104 High Alluvium 43 Low 1630-G South Sunkist Street Anaheim, California 92606 (714) 634-2092 (213) 652-4710 BORING NQ 8 DEPTH 5’ CONSOLIDATION -PRESSURE CURVE NORMAL LOAD IN KIPS PER SQUARE FOOT PLATE: PREPARED FOR Mola Development APPENDIX D Boring Logs and Site Plan W.O. 386901 1630-G South Sunkist Street Anaheim, California 92606 (714) 634-2092 (213) 652-4710 OJECT ~OLOGICAL :SCRtPTlON jpsoil xrace :posit SUMMARY SHEE-I Mola Developmenl - 4.2 - - 3t Y 3 .t; E - 2- X 4- 6- 8- O- 2 - 4- ENGINEERING CLAssIFrcATIoNrnssc~rPT~ou RED/BROWN, slightly silty, fine to coarse SAND, loose RED/BROWN, slightly silty, fine to coarse SAND, noderately compact, moist End @ 15' Vo Groundwater Encountered go Caving Occurred .BORING No. 1 ‘5. LVRFACEELE”. y+j’ ..~ -~~‘~ f :~ ,-.. &~.Backhoe ~44OLEDlA ',!4"-~. ~: LOCGEOBYJO~~ Klimuszko " -108 NO. .DATE 3869 5125 I83 ifi30-G South Sunkint Street Anaheim Calilcmia 92806 (714) 634-2092 (213) 852-4710 i ’ ,I .I t i ,$ ; .,. ‘: .y I N C: 0 R F 0 R A T !j: D axle No. D-105kJOl July 13, MC&3 Dcvel.opslent 606 Adnms Avenue Huntington Each, California %--‘w.m.- _..--' Attentioa: Mr. Chris Christy SlJbjeCt: CARLSBz~D TIt4CT 76-15, UXIT XCS; 1, 2 CARLSBU, CALL"ORNIA TR&'iS'.lT'PTAi . _i_ _ It is our understending that amther geotechnical consultant has been I-ctained by your firn ta provide an updated.geotachnicel investigation and to perforn testing and observation services dzring grading operations o:, the project. Siac2 6eocon, Incorporated uil: not be inwIved ir< the pscpnrction of the up<nted report or in provl.dini; test+:: an< obsarvrtio.. c /> e,rj.s '! _. d,.,r:ir,- g":i~1;~:,;< .;;::;dLLx3, WC z!Ut,‘ cl..c:,.iiill ally j..~.3.i~:lliij- .;T,;;r t;:<: perfoxance of the subject site. your new geotechnical consultant should provide written dncunentation to you and the City of Carlsbad indicating that, as the geotechnical consultant for the project, they arc satisfied with existing geotechnical recoamendations 0; have provided new recomendations, and that they wilYi assume all getitechnical engineering responsibility for the project. Wee also recodnend that they review and sign the project grading plans ;is t,he prcject grotcck.r;ical consultant. Please contact us :ii you have questions or if we can be of further service. very truly yours, I (1) addressee JFJ,: 1-m (1) \~,?I, Dell and Associ.atcs, kxorporated Attn: Hr. Bob Licver (1) City of Carlsbnd t3 ')$30 L)OWvI)V URIVE a SAX l)lliCO. CA1,IFORNlA ‘l21Zh 0 I'llON (iI‘?) Hi;-?h30 PRELIMINARY SOILS ENGINEERING INVESTIGATION TRACT No. 76-15 PALISADES POINT CARLSBAD, CALIFORNIA CONDUCTED FOR: MOLA 'DEVELOPMENT 808 ADAMS AVENUE HUNTINGTON.BEACH, CALIFORNIA 92648 -,~ W.O. 386901 JUNE 30, 1983 1630-G South Sunkist Street Anaheim, California 92806 (714) 634-2092 LOJECT EOLOGICAL ESCRWTION Bedrock SUMMARY SHEET Mola Develoument - - 1.4 - ,* z g P - I ! - i - j _ ENGINEERING CL~.SSIFICATIONIDESCR,~~,o~ ZREY/WHITE, silty, clayey SANDSTONE, dense, with lenses of GREENISH/GREY silty CLAYSTONE 3nd@lO' io Groundwater Encountered 10 Caving Occurred *ORtNG ND. 2 ~~~: /l.._ ,~- E&P. Backhoe -‘WOLE DIA. 24” . . LDGGEDBY John Xlimuszko JOB NO. ,D&TE SHEET OF 3869 5l35l8-3 7 17 <R’lLC Smtth S;lmkirl Strert Anaheim California 92606 (7141634-2092 [213~652-4710 / ! i 3 .,, ;. / E L ;OJECT edrock SUMMARY SHEET Mola Devw 18. - ,: ; 5; Ll 51 ;i - - 1.9 - x : 7 z z !&w&iet Wrest Anaheim California 92606 17141634-2092 1213) 652-4710 Anaheim California 92606 17141 634-2092 1213) 652-4710 - . 2- 4- 6. 8- o- 2 - 4 - 6' : =‘i 8: oE E3 3i i, - : - - ENGINEERING CCA.SSIF~CAT;TON~DESCRIPT~MJ GREY/WHITE, silty, 'clayey SANDSTONE, dense, moist, interbedded with hard, BROWN, silty CLAYSTONE lenses GREENISH/BROWN, silty CLAYSTONE, hard End @ 16' No Groundwater Encountered No kavitig Occurred .~~ -NORtNGNo. 3 ~' ._ "- ~, OURFACEELEV.~ --2gb ~; ‘,.-: ’ :..~ ‘.;,~‘,;; XO~IP. Backhoe, ~.*DLE DtA ~24" ~, LOGGEDBY' John Klimug%ko i f 3 .( i , 1 1 ‘_ ,i .’ ,. fz- I! PROJECT :OLOGICAL :SCRIPTtON ropsoil bedrock - 17.. a - !.( KEY/TAN, silty, sandy LAY. moist REY/WHITE, silty, clayey ANDSTONE, dense . 2- 4- 5- 3' I- ZOWN, silty CLAYSTONE, 3rd nd @ 10' J Groundwater Encountered 3 Caving Occurred I. - 31 t;; p’] - aORtNG No. 4 .~ " ~~.j., SURFACE ELEV. ,.~ ~.._ ~.~ roti~p. Backhoe -WOL~DIA ?4" : ='i 3: Di ;i -a 3i T ADGGEDBY JK '~ ._ .~ . ^ . ^. 1 .--L..- .--*I,-._:_ n”enc IV. a\ c-4 r)nn* ,O.O\ OC~-“74rl SUMMARY SHEET Mola Developmel - - - ENGINEERING CLASSIFICATIONIDESCRtPTlON ARK BROWN, sandy CLAY, Dist, loose d i .I 1 :i 3 . i , PR OJECT ,OLOGICAL ~SCRlPTlON .lluvium . SUMMARY SHEET ENGINEERING CLASS~F~CAT~ON~DESCR,PT,ON LED/BROWN, silty SAND 2- ED/BROWN, silty, clayey ;AND, ~moist, moderately :ompact, interbedded with iandy CUT 6- .2‘ LED/BROWN. slightly gravelly SAND, dense, .4- To Groundwater Encountered To~Caving Occurred - - - - aORtNG No. .5 SURFACE ELEV. ._~. .~ _~ SObtP. Backhoe :~-+tDLE DlA,24” ‘- LDGGEOW JK.' ', :I-'. - - - = ~fiRn-P. Srwtih S~mkict Street Anaheifn California 92606 17141 634-2092 I2131 652-4710 . {OJECT EG‘OGICAL ESCRIPT,ON Topsoil ierrace Deposit SUMMARY SHEET Mola Development - 09. - 1.l - *- s 3 cn s - 2 4 6 8 ,4 ,6 + E ; x - ENGINEERING CLASSIFICATIDNIDESCR~PT~ON ELLOWJBROWN, silty SAND, oose, slightly moist ED/BROWN to TAN, slightly ilty, fine to coarse SAND End @ 161 No Groundwater Encountered No Caving Occurred : %ORlNG NO. 6 ,~ ~“1. _:. SURFACE ELCV. - s&p. Backhoe ~~',O, &-2i"' ~‘ ~' : LOGGEOSY JK '1.' OJECT IOLOGICAL iSCRIPT,ON 511 “- I’, SUMMARY SHEET Mola DeveloDment .,- -7 W! $1 2; g: - , - z B $ 4 E ENGINEERING CLASSIFICATIONIDESCRlPTlON ff,o BROrJN, silty SAND, GREY/BROWN, clayey SAND, moderately compact, moist GREY, sandy CLAY, moist, extremely compact End @ 10' No Groundwater Encountered No Caving Occurred %ORlNG NO. 7~ _~.Y. .EURFACE ELEV. : 1 *,,bIP Backhoe +,oLED,A'~2$~' IOGGEO’SY JR '. '- ,:,,-- v .c*n s. c-.-L P....L:^. PIW^^, hd..h ~~sh,~i, a7rm ,714, fiRA-7nQ7 171R\ RS7-A710 ‘, , I 1 .I ; :; .-; I . . , L g :OJECT EOLOGICAL ESCRlPTlON Alluvium .’ 2,. ,. ..’ _.,. ,~ .,, SUMMARY SHEET Mola Development 15. - - 5: 5:: is “8 - 0. - 3f w P 2 E P - , - z B E 4 2 z f - 2‘ 4- 6- 8' O- ENGINEERING CLASS1FlCAlIONIDESCRIPTION ARK BROWN, silty SAND, ith roots, moderately oose ROWN, silty SAND, moist ED/BROWN, sandy CLAY/ layey SAND, moist, ntremely d&se nd @ 11' 3 Groundwater Encountered o Caving Occurred BORING No.. 8 s, sURF*CEELEV. :. ~.. .~~. :.- : :L_. E&P. Backhoe -llaO~E~~A 2~41' LOGGEOBY JK -, ': re*n e c....b* P..“b:-* PI...“, h-him ~~tihi~ a7anfi ,714, MA-7l-lP7 171RI RS7-A710 ,. ” ,~/ 1 :a 1 ‘? i fT L F PF 3OJECT EOLOGICAL NESCR~PT~ON 'opsoil .l'luvium SUMMARY SHEET Mola Developlgent - - , - t ~Z 0 F s t z - 2 4 6 8 - - % ij f Q 5 - ENGINEERING CLASSlFlCATlONtOESCRlPT,ON 3ROWN, silty SAND, loose, ky organics 3ROWN, silty SAND, noderately compact IARK BROWN/GREY, sandy XAY, moist, hard lense @ 5' YELLOW/BROWN, clayey SAND, iense, moist End @ 14' !Io Groundwater Encountered go Caving Occurred %ORlNG (3s. 9 _. SURFACE ELEV. .~ EO~IP. Backhoe MOLE DIA 24” ABGGEOBY JK‘ 1 ‘,~I 4 j ‘. ., Y .r*n P PI.&. E..^L:“. P.-w., bn..hnim twifrvnh a7mx~ ,714, K4A-7n~7 f7iRI AS7d71r.l . IOJECT EDLOGICAL ESCRlPTlON lluvium SUMMARY SHEET Mola Development . - 2 4 6 8 ENGINEERING CLASSIFICATlONIDESCRlPTlON ROWN, sandy CLAY, moist, 2derately loose ED/BROWN, silty, fine to 3arse SAND, mixed with layey SAND, moist nd@9' o Groundwater. Encountered o Caving Occurred %ORING No. 10 ~.. ‘Y,.~, SURFACE ELEV.. : _ y : eo,j,p~~ Backhoe ..;AoLE D,A-?%" '- LOGGED BY ,JK '~ . . . :I ,: *P?LP. Sns*h S~mkict Strmmt Anaheim Mifnrnia 92806 17141634-2092 12131852-4710 ,4 i 1 ! ,:t .$ . . 8 ;OJECT EOLOGICAL ESCRlFTlON illuvium SUMMARY SHEET X.1 2 4 6 ENGINEERING CLASSIFICATIONDESCRIFT~ON BROWN, silty SAND, moist YELLOW/BROWN, silty SAND, noderately compact and noist BROWN, sandy CLAY, moist, compact YELLOW/BROWN, clayey SAND, very compact End @ 11' No Groundwater Encountered No Caving Occurred SORING No. 11 ~~~ -' SURFACE ELEV. ‘: ZCIUIP: Backhoe ;nOLEk24” lOGGE0 BY JK -' '=I im-i-s Smtth !amkiet stw.?t Anahnim~ California 92806 1714) 634-2092 12131 852-4710 ! i p ,.I f ‘J! 3 . or, I PROJECT iEOL0GlCA.L lESCRlPTlON Soil Washed Downstream &om Earth Dam . .“. .~I .,~~.., SUMMARY SHEET Mola Development . I & :, : ‘3 ;a - - - x Au El t 3 - - . 2 4 6 ENGINEERING TAN, fine to medium SAND, loose, moist - RED/BROWN, fine to coarse SAND, moderately loose, moist End@9' No Groundwater Encounterei Caving from l'-6' - BORING No. 12 . . . LURFACE ELEV. _, _.:: ; EO~IP~ B&&hoe- -+IoL~o#& .24" LOGGED BY '~JK~ : '--~; ,,;,““- 1630-G South Sunkist Street Anaheim, Califwnia 92606 (714) 634-2092 (213) 852-4710 OJECT :OLOGlCAL :SCRIPTlON ,lluvium ,... ;.., ., ,~~?, .,1 .‘~. _. SUMMARY SHEET 16. 13. 24 15 18 - 1. 6. 8. L3< .5. - - - -, t ic .,2 i ,’ - 2- 4- 6- 8- LO- LZ- 14: 16' 18. 20. !2- ,4- !6- !8- 30- 32- 34. 36. - L u Y .z E P, 0 - ENGINEERING CLASSIFICATIONR)ESCRIPTION lROWN, silty SAND, slightly loist, porous aDDISH/BROWN, silty, slightly clayey SAND, noist, slightly compact Lenses of GRAVEL @ 10" jome cobbles (2" to 3" in iiameter), and GRAVEL @ !2' Zlayey @ 29' Clayey SAND below 32' eORlNG No. ..~.‘~I,.. “- ~,.- ~-. .EURFAtEELEV. lti:- ~~ Bucket .' EObtP. Auger :%lOLEDlA 38” ‘. LOGGED BY .JR Y ,,'i / c ,' : ,. 4 4T L EOLOGKAL ESCRlPTlON bedrock ,I -. ., ,_ .~. ~, SUMMARY SHEET Mola Development 5.: .3.t E w 2 E P - ,.z z 0 2 5 2 2 38 110 $2 54 c ‘Y : ; : r - - - : g II ‘ $E E2 SE - ENGINEERING CLASSIFICATIONIDESCRlPTlON :REY/WHITE, silty, clayey lANDSTONE, dense : .” ‘~~ ; ;RE;(BROWN CLAYSTONE, dens :nd @ 44’ lo Groundwater Encountered lo Caving Occurred _ ~., -.. .‘~’ SORING No. 1 EVRFACE ElEV. -~ 16 2 ‘.~ I Bucket fou'P' Auger. iHOLE D,A 18” _' LOGGEDBY JK .f ox 1 1 c j I f : . . IJECT 3LOGlCAL ECRIPTION lluvium edrock SUMMARY SHEET . Mola Development ~.. ” 1 i : * i I 6 87 0' 2- 4- 6- 8- :0- - ‘ I .4 , , ~1 . , / ENGlNEERlNG CLASSIFICATIONIDESCRlPTlDN ROWN, clayey SAND, / lightly moist, porou8, .oist @ 2' ARK BROWN, silty, s&dy LAY, moist, compact :REY/BROWN, clayey ANDSTONE MITE, slightly silty lANDSTONE, dense, slightly loist ;nd @ 20’ ;c: ~~. :‘. -’ lo GroundwaterEncountered lo Caving Occurred SORING No. 2 ~,~ ~,~.~ T,: -.-~- z -SURFACE ELEV. 1.86; 0' Bucket xobtP. Auger r+(OLEDIA .~lg" .iOGGEDBY JK -$q-Y$g -~ ‘, s: :‘I : 1 ,‘i :{ * ‘: i ,’ i iz 1 - IOJECT EDLDG~CAL ESCRlPTlGN 3edrock SUMMARY SHEET 14.1 2. 6‘ 8' 10. 12. 14' 16- 18. 20. 22. 24. 26. 28‘ 30. 32. 34 .,a - , =‘i 0,; gij Y! 3; Y ENCtNEERING CLASSIFICATIONmESCAIPTION :REY/WHITE. silty. clavev. iine.to co&-se SGDSTOkE-,. loist, dense :AN, silty, fine to medium XiDSTONE, moist, dense :REY/WHITE, silty, clayey, rine to coarse SANDSTONE CAN, silty, fine to mediurr UNDSTONE, dense XEY/WHITE, ~silty, clayey SANDSTONE, moist, dense End @ 35' qo Groundwater Encountered yo Caving Occurred. ~:' . . ~BDRlNGNo. 3 ~-~.~- ;-I ;‘.^~; SURFACE ELEV. Bucket ,. ' :'~ L&P. Auger “+N,LEDIA. 18”~ : LOGGEDBY JK : JOB ND. DATE SHEET 3869 617183 40c4 Mola Development APPENDIX E Geological Report W..O.' 386901 1630-G South Sunk&t Street Anaheim, California 92606 (714) 634-2092 (213) 652-4710 Baseline Consultants Inc. 15307 MINNESOTA AVE. SOILS ENGINEERING-ENGMERING GEOLOGY PARAMOUNT, CALI F. 90723 (213) 633-8152 July 6, 1983 Your Job No. 3869 Project No. 1109-053 Action Engineering Consultants 1630-G South Sunkist Street Anaheim, California 92806 Attention: Mr. Bruce Packard Subject Reference: Engineering Geology Investigation Tentative Tract No. 76-15 El Camino Real, Tamarack Avenue Carlsbad, California Owner : Mola Development Engineer: Van Dell and Associates, Inc. Soil Engineer: Action Engineering Consultants Gentlemen: This report describes an investigation of the engineering geologic conditions at the site of a proposed sixty (?) acre residential development, located west of El Camino Real and northerly of Tamarack Avenue in Carlsbad, California. The purpose of this investigation was to determine the surficial and subsurficial geologic conditions as they would relate to the proposed development, and to delineate the character and limits of possible geologic hazards, if found to be present. In addition, comments concerning the seismicity of the site were elicited, as well as recommendations to mitigate possible hazards requested. Project No. 1109-053 Action/Mola/Carlsbad -2- To this end, portions of four days were spent in the field, mapping exposed features, and noting physical characteristics of the landforms deemed pertinent. We were provided a 40 scale topographic-preliminary grading plan, upon which we have plotted our field data (see Plates 2a, 2b, 2c, and 2d). Geologic cross sections based upon this map, and the geologic conditions encountered, are presented on Plates 3a. 3b. 3c, 3d, 3e, 3f, 3g, and 3h. TERRAIN CONDITIONS The subject property encompasses remnants of an old, eroded mesa, and the steep side slopes of the mesa, which lead down to El Camino Real along the eastern property line. Substantial housing developments bound the property to the north, south, and west, and vacant, open ground exists to the east, across El Camino Real. Plate 1, Vicinity Map, depicts the location of the site in relation to general topography, streets, and land- marks. The natural topographic features of portions of the tract, especially the southern portion, have been substantially modified by past grading which has created cut slopes, fill slopes, fill masses, roadways, and an extensive series of debris basins in the southernmost canyon 'above the existing terminus of Tamarack Avenue. In addition, it appears that substantial filling has taken place in the areas of proposed Lot Nos. 69 through 76. Project No. 1109-053 Action/Mola/Carlsbad -3- EARTH MATERIALS 1. Artificial Fill (Map Symbol Af) Artificial fill was observed on two pad areas, just inside the tract boundary near Skyline Drive , on the slopes below Neblinda Drive, in the southern canyon area, in the flat zone easterly of Palisades Drive, and in small, isolated dump areas of the tract. In most cases, the fill appeared only moderately compact at best, and very loose at worst. Severe erosion has taken place in the fill deposits from uncontrolled drainage, over the years since placement. 2. Residual Soils A mantle of residual soil has developed over the natural materials of the area, which consist primarily of one to three feet of loose, porous, silty and clayey, fine sand. 3. Alluvium (Map Symbol Qal) The central, eastern, and southeastern portions of the property within the drainage areas are underlain by alluvial soils, consisting of primarily clayey sands and sandy clays. In general, the uppermost six to nine feet of the alluvium is considered soft to loose and porous in nature. Estimated maximum thickness of the alluvium is forty-five feet. Project No. 1109-053 Action/Mola/Carlsbad -4- 4. Terrace Deposits (Map Symbol Qt) Mantling remnants of the mesa along the westernad northern parts of the tract, are terrace deposits consisting of moderately compact to dense, red-brown, silty sands, with occasional lenses of clayey sand and small gravel. Maximum thickness of this unit is estimated to be Sixty feet. 5. Bedrock (Map Symbol Tss) Underlying the entire hillside area , and outcropping in numerous exposures, are Tertiary Marine Sediments consisting of white to tan-gray, silty and clayey sandstone, containing minor interbeds, lenses, and pockets of green-gray, silty clay. The uppermost zones of the bedrock, that is, those which directly underlie the Terrace Deposits, are whitish gray, friable, silty sands, which, when eroded, develop into "badlands“ topography. The more clayey portions of the unit which underlie the lower parts of the tract are exposed on the easterly trending ridges , and develop a thicker, more cohesive soil cover. In all cases, the bedrock was found to be very compact to dense, and quite friable. Bedrock Structure Bedding attitudes in the bedrock were very rare, however, obscure indications point to a west-dipping homocline, with an apparent dip of five to seven degrees. Project No. 1109-053 Action/Mola/Carlsbad -5- A small, discontinuous, non-active fault was noted near the southern property line, which has caused local variation in the overall regional dip near the fault. SEISMICITY Active faults'are believed to be absent from the property, and the closest known active faulting would be associated with the Elsinore Fault, located about 20 miles easterly of the site. Because of this, the only seismic consideration deemed appropriate would be that of ground shaking generated by a distant fault. This movement should be no more severe than that to be experienced by the currently developed, nearby residential areas. MASS MOVEMENT No landslides, soil slumps, mudflows, or other indications of instability were apparent in the natural materials on the property. The majority of the existing fill materials, however, are considered marginally stable and subject to severe erosion under concentrated run-off. GROUNDWATER Groundwater is believed to be below any zone that could effect the proposed development. Project No. 1109-053 Action/Mola/Carlsbad CONCLUSIONS AND RPCONMENDATIONS -6- Favorable Conditions 1. The vast majority of the on-site materials, excluding any debris- laden fills, are satisfactory for use in the proposed fills. 2. The earth materials on the property can readily be excavated by heavy duty earthmoving equipment. 3. No landslides, or signs of mass movement , are present on the property. 4. Active faults are not known to be present on or beneath the site, or in the immediate vicinity. 5. Bedrock is considered more than adequate to support structural loads. 6. Bedrock attitudes appear favoarable positioned for continual gross stability. 7. Groundwater is not anticipated to be a problem. Generally Unfavorable Conditions 1. The existing on-site fills are not considered suitable in their present state for the proper support of new fill, or structures, and should be removed in advance of the planned grading. Suitability for reuse should be determined by the soils engineer. 2. The alluvial materials within the drainage areas and in the small tributary canyons are quite soft, and probably unsuitable to support fill or structural loads in their present state. Project No. 1109-053 Action/Mola/Carlsbad -7- 3. Most of the near surface materials in the lower portions of the tract appear to be moderately to highly expansive. 4. Surchared cut slopes (fill over cut) will require special considera- tion in design. 5. The on-site materials are highly susceptible to severe erosion under concentrated flow, especially the upper units of the bedrock and the Terrace Deposits. 6. Buttressing and/or stabilization will probably be necessary on those cut slopes which expose the clayey portions of the bedrock, especially those that expose the clay near the planned toes of slope. Such special grading designs will, of necessity, have to be developed as grading progresses, and during on-going geologic examination. For purposes of this report, however, the following lots x expose such conditions; Lot Nos. 4 through 23, 53 through 56, 63 through 66, 90 through 92, 99 through 109, and 130 and 131. General Conclusions Based upon our field observations, and our geologic interpretation of the conditions encountered, it is the opinion of the writer that development of the property, as contemplated, is feasible from the engineering geology viewpoint, provided that; the recommendations of this report are followed, that good engineering practices are adhered to, and that the designs and recommendations are properly implemented. Project No. 1109-053 Action/Mola/Carlsbad -a- Recommendations 1. 2. 3. 4. 5. Disposition of the fill masses should be under the direction and supervision of the soils engineer. Foundation systems should be embedded in the firm, natural materials, and/or compacted fill, the bearing pressures and associated criteria of which shall be determined by the soils engineer. Unretained cuts in the Terrace Deposits or bedrock shall be no steeper than 26 degrees (2:l). unless stability analyses by the soils engineer demonstrate that steeper slopes will be stable, and no permanent, unsupported slopes in the alluvium shall be made. Where footings are to be constructed on or near a slope, it is recommended that the bottom outside edge of such footings be a minimum of five feet from the slope face. All roof and pad drainage should be conducted to the planned paved streets, and/or storm drains. Remarks It is anticipated that the subsurface conditions will not vary significantly from those observed. However, should unexpected conditions arise during grading, this office shall be notified so that we may be in a position to change or modify the recommendations. We reserve the right to review final grading plans prior to actual construction to verify compliance with the recommendations. Project No. 1109-053 Action/Mola/Carlsbad -9- This investigation was made in accordance with generally accepted engineering geology procedures, and within the limits prescribed by the client. No other warranty, expressed or implied, is made as to the professional advice included in this report. Respectfully submitted, BASELINE CONSULTANTS, INC. RPC/ac Distribution: (8) Action Engineering APPENDIX A Af - Qal - Qt - Tss - 0 Y- /- /(, .’ / - I Artificial Fill Alluvium Deposits Terrace Deposits Sandstone Bedrock Strike and Dip Geologic Contact Buried Geologic Contact Fault Geologic Cross Section Carlsbad, California BASELINE CONSULTANTS !. ‘s VICINITY MPD . .- ..-.. . ._.. . . i \ Engineering Geology Investigation Carlsbad Tract 76-15 Carlsbad, California t 1 JOB No-llog-053 ) PLATE 1 c BASELINE CONSULTANTS 1