Loading...
HomeMy WebLinkAboutCDP 16-06; BAPTIE RESIDENCE; RESPONSE TO CITY OF CARLSBAD PLAN CHECK COMMENTS; 2017-03-28, • ', EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE "I" SANTEE, CALIFORNIA 92071 (619) 258-7901 Fax 258-7902 Ken & Sandra Baptie P. 0. Box 1221 Woodinville, Washington 98072 Subject: Response to City of Carlsbad Plan Check Comments Proposed Single-Family Residence 5070 Carlsbad Boulevard Carlsbad, California 92008 CDP 16-06 March 28, 2017 Project No. 16-1126F2 Reference: "Limited Geotechnical Investigation (Revised Preliminay), Proposed Single-Family Residence, 5070 Carlsbad Boulevard, Carlsbad, California 92008, CDP 16-06", Project No. 16-1126F2, Prepared by East County Soil Consultation and Engineering, Inc., Dated December 22, 2016. Dear Mr. & Mrs. Baptie: In accordance with your request, we have prepared this report to address the City of Carlsbad Plan Check comments for the proposed single-family residence at the subject site. 1. Please find attached the geologic/ geotechnical map and cross-sections on separate plates. 2. We have reviewed the temporary shoring plans (SH-1 through SH-3) prepared by BergerABAM of San Diego, California and dated 11/22/16 for the Baptie residence. The plans were found to be in accordance with the recommendations provided in the referenced geotechnical report. In addition, the temporary lH: lV cut slope from the top of the shoring to the property lines will not have an adverse impact on the adjacent properties. If we can be of further assistance, please do not hesitate to contact our office. Mamadou Saliou Diallo, P .E. RCE 54071, GE 2704 MSD/md RECEIVED AY!~ 13 2017 RECORD copy d(c..-_fe/r/n- 1n1t1a1 Date ·- t I ' I -G i I ~ k ~ ~ * ½ ~ ~ I ' I I ' i 1~ 1--'·o" l'L-..-.w. -... ~ ~r...,T...&L,-..... ,..._..,.&>4.~\s E.c1•'TINC-J" -------4JI c:;.Nu '-LT.,,,N ... c....:r ........... ~pp~~i .. P.,:T'•---~ i,.i,_.__ ' ~o1-c• 1111•-"'-'I ,.. . ..,.. ...... ~- 9.'1"J--, ,~ 6WG! i I 1,t, t I \.;., ~ •Jll1·11·111JUIHJ-, _ _J ' , ., q1\ I ..-•. 'l' .. .::l!~o" >! ~ ~ l""ZO I EAST COUNTY SOIL CONSULTATION & ENGINEERING, INC. 10925 HARTLEY RD .. SUITE I, SANTEE. CA 92071 (619) 258-7901 Fax (619) 258-7902 ~.,.z- ~ cx;&W;e~Jey 80~1/0le ~ ~t-o/>!31VA6t-i (c,~) ):::eflf,'~~~e~ Ge°o~G/C / 6',eo~/1//Dtk-m"170 -~·#!"*CH :2dr 'UJ/7 .· /~-//2'6r2 I ~ /YP. / • ,; - i~ ~~ ~~ \ti ~ .1~/ t I ·rr-rrl77:r//mil1 ikz!@l?,,-~/7,l/l/R/!I/! . /lle!l1f'J ~1V'/r et..;~ /li4//1.:.G-~ lJjg!, . /f#i. =- CJ?L'J.Sf5-~o/\i ,4--A ~c /lf:='?t)I ~ A~ f f~)i t M~ ~slJJ ?,b EAST COUNTY SOIL CONSULTATION & ENGINEERING, INC. I 0925 HARTLEY RD .. SUITE I. SANTEE, CA 92071 (619) 258-7901 Fax (619) 258-7902 ~-~tJ/IG if t:"IZ~-4t::C17tJN 5-B ~~ /~?0/ ).a3v r ~4e4 ~ ~01~ ~',,#"1fCh1 ui ;1,t?/7 . /1-/126',Cz. I ~ 1ttJ. -z EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE "I" SANTEE, CALIFORNIA 92071 (619) 258-7901 Fax 258-7902 Ken & Sandra Baptie P. 0. Box 1221 Woodinville, Washington 98072 Subject: Limited Geotechnical Investigation (Revised Preliminary) Proposed Single-Family Residence 5070 Carlsbad Boulevard Carlsbad, California 92008 CDP 16-06 Dear Mr. & Mrs. Baptie: December 22, 2016 Project No. 16-1126F2 In accordance with your request, we have performed a limited geotechnical investigation at the subject site to discuss the geotechnical aspects of the project and provide recommendations for the proposed development. Our investigation has found that the proposed building pad is underlain by topsoil and slopewash to a maximum depth of approximately 2.5 feet below existing grade. These soils were underlain by dense terrace deposits to the explored depth of 10 feet. It is our opinion that the development of the proposed residence is geotechnically feasible provided the recommendations herein are implemented in the design and construction. Should you have any questions with regard to the contents of this report, please do not hesitate to contact our office. Mamadou Saliou Diallo, P .E. RCE 54071, GE 2704 MSD\md IlECORD COPY IniOal ' KEN & SANDRA BAPTIE/C"'ARLSBAD BOULEVARD PROJECT NO. 16-l 126F2 TABLE OF CONTENTS INTRODUCTION ............................................................................................................................................ (.3 I SCOPE OF SERVICES .................................................................................................................................... ;.3 SITE DESCRIPTION AND PROPOSED CONSTRUCTION ...................................................................... i.3 FIELD INVESTIGATION AND LABORATORY TESTING ...................................................................... (.4 GEOLOGY ......................................................................................................................................................... 4 Geologic Setting .................................................................................................................................. ;.4 Site Stratigraphy .................................................................................................................................. ~.4 i SEISMICITY .................................................................................................................................................... j •• 5 Regional Seismicity ............................................................................................................................. / .. 5 Seismic Analysis ................................................................................................................................ .; .. 5 2013 CBC Seismic Design Criteria .................................................................................................... ; .. 6 Geologic Hazard Assessment. ............................................................................................................. : .. 6 GEOTECllNICAL EVALUATION ............................................................................................................... : .. 7 Compressible Soils ............................................................................................................................. ( 7 Expansive Soils ................................................................................................................................... ! .. 7 Groundwater ....................................................................................................................................... ) .. 8 CONCLUSIONS AND RECOMMENDATIONS ......................................................................................... ; .. 8 CLEARING AND GRUBBING ...................................................................................................................... J .. 8 I FOUNDATIONS AND SLABS ..................................................................................................................... , .. 8 SETTLENIENT ................................................................................................................................................ ) .. 9 PRESATURATION OF SLAB SUBGRADE ................................................................................................ i..9 RETAINING WALLS ........................................................................................................................................ 9 TEMPORARY SLOPES ................................................................................................................................. 1 I 0 TRENCH BACKFILL ...................................................................................................................................... 10 DRAINAGE ..................................................................................................................................................... ; 10 I FOUNDATION PLAN REVIEW ................................................................................................................... ; 11 LIMIT A TIO NS OF INVESTIGATION ........................................................................................................ ; 11 ADDITIONAL SERVICES ........................................................................................................................... l 12 PLATES Plate 1-Location of Exploratory Boreholes Plate 2 -Summary Sheet (Exploration Boreholes and Boring) Plate 3 -USCS Soil Classification Chart PAGE L-1, LABORATORY TEST RESULTS ............................................................................................. 1.14 REFERENCES ................................................................................................................................................ ,. 15 2 KEN & SANDRA BAPTIEICARLSBADBOULEVARD PROJECT NO.16-1126F2 INTRODUCTION This is to present the findings and conclusions of a limited geotechnical investigation jfor a proposed two-story, single-family residence over a partial basement to be located at 5070 Cai!lsbad I Boulevard, in the City of Carlsbad, California. · The objectives of the investigation were to evaluate the existing soils conditions and prpvide recommendations for the proposed development. SCOPE OF SERVICES The following services were provided during this investigation: 0 Site reconnaissance and review of published geologic, seismological and geotechnical r~ports and maps pertinent to the project area · 0 Subsurface exploration consisting of three (3) boreholes within the limits of the propose</i area of development. The boreholes were logged by our Staff Geologist. ' 0 Collection of representative soil samples at selected depths. The obtained samples were ~ealed in moisture-resistant containers and transported to the laboratory for subsequent analysis.! I 0 Laboratory testing of samples representative of the types of soils encountered during the field investigation 0 Geologic and engineering analysis of the field and laboratory data, which provided the[basis for our conclusions and recommendations · 0 Production of this report, which summarizes the results of the above analysis and presents our findings and recommendations for the proposed development SITE DESCRIPTION AND PROPOSED CONSTRUCTION i The subject site is a rectangular-shaped residential lot located on the east side of C~sbad Boulevard, in the City of Carlsbad, California. The property, which encompass an arta of approximately 6,600 square feet (11 0' X 60') is vacant with an approximately 8-foot high cut slope descending to Carlsbad Boulevard. The building pad slopes gently to the west. Vegetation consisted of grass and a few trees. Site boundaries include Carlsbad Boulevard to the wes~ and similar residential developments to the remaining directions. The preliminary plans prepared by Wright Design of Carlsbad, California indicate the proJ!,osed construction will include a single-family residence. The structure will be two-story, wood-framed over a partial basement and founded on continuous footings with slab-on-grade floors. 3 KEN & SANDRA BAPTIEICARLSBADBOULEVARD PROJECT NO. 16-1126F2 FIELD INVESTIGATION AND LABORATORY TESTING I I On January 14, 2016, three (3) boreholes were excavated to a maximum depth of approximat~ly 10 feet below existing grade with a hand auger. The approximate locations of the boreholes are s),.own on the attached Plate No. 1, entitled "Location of Exploratory Boreholes". A continuous log bf the soils encountered was recorded at the time of excavation and is shown on Plate No. 2 entitled "Summary Sheet". The soils were visually and texturally classified according to the l filed identification procedures set forth on Plate No. 3 entitled "USCS Soil Classification". 1 Following the field exploration, laboratory testing was performed to evaluate the pertinent engineering properties of the foundation materials. The laboratory-testing program included moisture and density, particle size analysis and expansion index tests. These tests were perftjrmed in general accordance with ASTM standards and other accepted methods. Page L-1 and Plate ~o. 2 provide a summary of the laboratory test results. • GEOLOGY Geologic Setting I The subject site is located within the southern portion of what is known as the Peninsular Ranges Geomorphic Province of California. The geologic map pertaining to the area (Reference l'fo. 4) indicates that the site is underlain by Pleistocene marine terrace deposits (Qt). Site Stratigraphy I I The subsurface descriptions provided are interpreted from conditions exposed during the! field investigation and/or inferred from the geologic literature. Detailed descriptions of the subs*1-face materials encountered during the field investigation are presented on the exploration logs proviqed on Plate No. 2. The following paragraphs provide general descriptions of the encountered soil types: Topsoil i Topsoil is the surficial soil material that mantles the ground, usually containing roots and other ofganic materials, which supports vegetation. Topsoil was observed in all boreholes with a thickn~ss of approximately 12 to 18 inches. It consisted of dark brown, silty sand that was moist, loose and porous in consistency with some organics (roots and rootlets). Slopewash (Qsw) Slopewash was encountered under the topsoil with a thickness of approximately 12 inches. It consisted of light brown, silty sand that was dry to moist and loose in consistency. 4 KEN & SANDRA BAPTJEI CARLSBAD BOULEVARD PROJECT NO. 16-J 126F2 Marine Terrace Deposits (Qt) Marine terrace deposits were observed below the topsoil layer. They generally consisted of rek!dish brown, silty sand that was moist and medium dense to dense in consistency. · SEISMICITY Regional Seismicity Generally, Seismicity within California can be attributed to the regional tectonic movement tW<ing place along the San Andreas Fault Zone, which includes the San Andreas Fault and most Po/allel and subparallel faults within the state. The portion of southern California where the subject $ite is located is considered seismically active. Seismic hazards are attributed to groundshaking ! from earthquake events along nearby or more distant Quaternary faults. The primary factqrs in evaluating the effect an earthquake has on a site are the magnitude of the event, the distance I from the epicenter to the site and the near surface soil profile. · According to the Fault-Rupture Hazard Zones Act of 1994 (revised Alquist-Priolo Special S~dies Zones Act), quaternary faults have been classified as "active" faults, which show apparent stpiace rupture during the last 11,000 years (i.e., Holocene time). "Potentially-active" faults are those raults with evidence of displacing Quaternary sediments between 11,000 to 16,000 years old. Seismic Analysis Based on our evaluation, the closest known "active" fault is the Rose Canyon Fault located approximately 4 miles (6.5 kilometers) to the east. The Rose Canyon Fault is the design fault of the project due to the predicted credible fault magnitude and ground acceleration. The Seismicity of the site was evaluated utilizing the 2008 National Seismic Hazard Maps fror.1 the USGS website and Seed and Idriss methods for active Quaternary faults within the re&ional vicinity. The site may be subjected to a Maximum Probable Earthquake of 6.9 Magnitude ~long the Rose Canyon fault, with a corresponding Peak Ground Acceleration of 0.45g. The max,mum Probable Earthquake is defined as the maximum earthquake that is considered likely to pccur within a 100-year time period. · The effective ground acceleration at the site is associated with the part of significant ground motion, which contains repetitive strong-energy shaking, and which may produce Struftural deformation. As such, the effective or "free field" ground acceleration is referred to ~s the Repeatable High Ground Acceleration (RHGA). It has been determined by Ploessel and Slpsson (1974) that the RHGA is approximately equal to 65 percent of the Peak Ground Accelerati4n for earthquakes occurring within 20 miles of a site. Based on the above, the calculated Cnpdible RHGA at the site is 0.29g. 5 KEN & SANDRA BAPTIEICARLSBAD BOUL EVARD PROJECT NO. I 6-1 126F2 2013 CBC Seismic Design Criteria A review of the active fault maps pertaining to the site indicates the location of the Rose Canyon Fault Zone approximately 6.5 km to the east. Ground shaking from this fault or one of the major active faults in the region is the most likely happening to affect the site. With respect to this hazard, the site is comparable to others in the general area. The proposed residential structure should be designed in accordance with seismic design requirements of the 2013 California Building Code or the Structural Engineers Association of California using the following seismic ~esign parameters: PARAMETER . VALUE 2013 CBC and ASCE 7 REFERENCES Site Class D Table 20.3-1/ ASCE 7, Chapter 20 Mapped Spectral Acceleration For Short Periods, 1.173g Figure 1613.3.1(1) Ss Mapped Spectral Acceleration For a I-Second 0.451g Figure 1613.3 .1(2) Period, S1 Site Coefficient, Fa 1.031 Table 1613.3.3(1) Site Coefficient, f v 1.549 Table 1613.3.3(2) Adjusted Max. Considered Earthquake Spectral 1.209g Equation 16-37 Response Acceleration for Short Periods, SMs Adjusted Max. Considered Earthquake Spectral 0.699g Equation 16-38 Response Acceleration for I-Second Period, SM t 5 Percent Damped Design Spectral Response 0.806g Equation 16-39 Acceleration for Short Periods, Sos I 5 Percent Damped Design Spectral Response 0.466g Equation 16-40 Acceleration for I -Second Period, SDI Geologic Hazard Assessment Ground Rupture Ground rupture due to active faulting is not considered likely due to the absence of known fault traces within the vicinity of the project; however, this possibility cannot be completely ruled out. The unlikely hazard of ground rupture should not preclude consideration of "flexible" design for on-site utility lines and connections. Liquefaction Liquefaction involves the substantial loss of shear strength in saturated soils, usually sandy soils with a loose consistency when subjected to eruthquake shaking. Based on the consistency of the underlying terrace deposits, it is our opinion that the potential for liquefaction is very low. 6 KEN & SANDRA BAPTIEI CARLSBAD BOULEVARD PROJECT NO. 16-1126F2 Landsliding There is no indication that landslides or unstable slope conditions exist on or adjacent to the ptoject site. There are no obvious geologic hazards related to landsliding to the proposed developmJnt or adjacent properties. : Tsunamis and Seiches The site is not subject to inundation by tsunamis due to its elevation. The site is also not subj~ct to I seiches (waves in confined bodies of water). 1 GEOTECHNICAL EVALUATION Based on our investigation and evaluation of the collected information, we conclude that the proiposed construction is feasible from a geotechnical standpoint provided the recommendations provided q.erein will be properly implemented during structural development. · In order to provide a uniform support for the proposed structure, footings should be excavated into the dense terrace deposits. The new foundations may consist of reinforced continuous and/ or spread footings with reinforced slabs. Recommendations and criteria for foundation design are provided in the Foundation and Slab recommendations section of this report. ] Compressible Soils Our field observations and testing indicate low compressibility within the dense terrace deposits, which underlie the site. However, loose topsoil and slopewash were encountered to a maximum ~epth of approximately 2.5 feet below surface grades. These soils are compressible. Due to the potenti~ for soil compression upon loading, remedial grading of these soils, including overexcavatiori and recompaction will be required unless footings are extended to the dense terrace deposits. Following implementation of the recommendations presented herein, the potential for; soil compression resulting from the new development has been estimated to be low. The low-settl~ment assessment assumes a well-planned and maintained site drainage system. Expansive Soils An expansion index test was performed on a representative sample of the terrace deposits to determine volumetric change characteristics with change in moisture content. An expansion index of 5 was obtained which indicate a very low expansion potential for the foundation soils. 7 KEN & SANDRA BAPTIEICARLSBAD BOULEVARD PROJECT NO. 16-1126F2 Groundwater Static groundwater was not encountered to the depths of the boreholes. The subject site is lopated at an elevation of approximately 55 feet above Mean Sea Level. We do not expect groundwajter to affect the proposed construction. Recommendations to prevent or mitigate the effects ofi poor surface drainage are presented in the Drainage section of this report. CONCLUSIONS AND RECOMMENDATIONS The following conclusions and recommendations are based upon the analysis of the dat1 and information obtained from our soil investigation. This includes site reconnaissance; i field investigation; laboratory testing and our general knowledge of the soils native to the site. The $ite is suitable for the proposed residential development provided the recommendations set fort~ are implemented during construction. · CLEARING AND GRUBBING The area of the proposed construction should be cleared of vegetation and deleterious materials. Vegetation and debris from the clearing operation should be properly disposed of off-site. The area should be thoroughly inspected for any possible buried objects, which need to be rerouted or re~oved prior to construction. All holes, trenches, or pockets left by the removal of these objects shotjld be properly backfilled with compacted fill materials. · Our field investigation indicates that dense terrace deposits underlie the site at shallow depths. These soils will be adequate for the support of the proposed structure without detrimental settlement. However, for slab. support in the main floor area, we recommend overexcavatiof and recompaction of the upper 2 feet of subgrade. Foundation excavations should be observed b1Y our representative to verify competent bearing soils. FOUNDATIONS AND SLABS a. Continuous and spread footings are suitable for use and should extend to a minimum depth pf 24 inches below the lowest adjacent grade for the proposed two-story structure over basei;nent. Continuous footings should be at least 18 inches in width and reinforced with a minimum of four #4 steel bars; two bars placed near the top of the footings and the other two bars placed ne¥ the bottom of the footings. Continuous footings for the main floor may be 18-inch deep and 1 ~-inch wide and reinforced as above. Isolated or spread footings should have a minimum width of 24 inches. Their reinforcement should consist of a minimum of #4 bars spaced 12 inches on ¢enter (each way) and placed horizontally near the bottom. The minimum reinforcement recommen4ed is based on soil characteristics and is not intended to supersede the structural engineer requirements. b. Interior concrete floor slabs should be a minimum 4 inches thick. Reinforcement should c~nsist of #3 bars placed at 16 inches on center each way within the middle third of the slabs by supp~rting the steel on chairs or concrete blocks "dobies". The slabs should be underlain by 2 inches of iclean sand over a 10-mil visqueen moisture barrier. The effect of concrete shrinkage will result in qracks in virtually all-concrete slabs. To reduce the extent of shrinkage, the concrete should be placed at a 8 KEN & SANDRA BAPTJE/ CARLSBAD BOULEVARD PROJECT NO. 16-l 126F2 maximum of 4-inch slump. The minimum steel recommended is not intended to prevent shri~age cracks. Actual slab thickness and reinforcement may be designed by the project structural en~ineer using a coefficient of subgrade reaction of 250 pci. : c. Where moisture sensitive floor coverings are anticipated over the slabs, the 10-mil plastic moisture barrier should be underlain by a capillary break at least 2 inches thick, consisti~g of coarse sand, gravel or crushed rock not exceeding 3/4 inch in size with no more than 5 p~rcent passing the #200 sieve. 1 d. An allowable soil bearing value of 2,000 pounds per square foot may be used for the desi~ of continuous and spread footings at least 12 inches wide and founded a minimum of 12 inche$ into the dense terrace deposits as recommended in the 2013 California Building Code, Table 1806.2. ! This value may be increased by 400 psf for each additional foot of depth or width to a maximum yalue Of 6,000 lb/ft2. I i e. Lateral resistance to horizontal movement may be provided by the soil passive pressure anid the friction of concrete to soil. An allowable passive pressure of 250 pounds per square foot pd foot of depth may be used. A coefficient of friction of 0.35 is recommended. The soils passive pressure as well as the bearing value may be increased by 1/3 for wind and seismic loading. ' SETTLEMENT Since footings for the proposed structure are anticipated to be supported by the dense tfirrace deposits, total and differential settlement should be within acceptable limits. PRESATURATION OF SLAB SUBGRADE Because of the granular characteristics of the subgrade soils, presoaking of subgrade pripr to concrete pour is not required. However, subgrade soils in areas receiving concrete should be watered prior to concrete placement to mitigate any drying shrinkage, which may occur follqwing foundation excavation. RETAINING WALLS Cantilevered retaining walls should be designed for an "active" lateral earth pressure of 35 psf/ft (35 pcf EFP) for approved granular backfill and level backfill conditions. Cantilever walls subj¢ct to uniform surcharge loads should be designed for an additional uniform lateral pressure equal toi one- third (1/3) the anticipated surcharge pressure. 1 Restrained walls such as basement walls should be designed utilizing an "at-rest" earth pressure pf 60 psf/ft (60 pcf EFP) for approved granular and level backfill. Restrained walls subject to uniform surcharge loads should be designed for an additional uniform lateral pressure equal to one-halfi(l/2) the anticipated surcharge. For earthquake motions, additional lateral pressures of 26 and 39 pcf (EFP) may be applied for non restrained and restrained conditions respectively using an inverted triangular distribution if requir¢d. 9 KEN & SANDRA BAPTIEICARLSBAD BOULEVARD PROJECT NO. 16-l 126F2 Soil design criteria, such as bearing capacity, passive earth pressure and sliding resistanye as recommended under the Foundation and Slab recommendations section, may be incorporated into the retaining wall design. · Footings should be reinforced as recommended by the structural engineer and appropriate I back drainage provided to avoid excessive hydrostatic wall pressures. As a minimum we recomm~nd a fabric-wrapped crushed rock and perforated pipe system. At least 2 cubic feet per linear foot o:ff free- drainage crushed rock should be provided. · The remaining wall backfill should consist of approved granular material. This fill material should be compacted to a minimum relative compaction of 90 percent as determined by ASTM D11557 test method. Flooding or jetting of backfill should not be permitted. Granular backfill sho~ld be capped with 18 inches (minimum) of relatively impervious fill to seal the backfill and p*vent saturation. It should be noted that the use of heavy compaction equipment in close proximjty to retaining structures can result in wall pressures exceeding design values and corresponding] wall movement greater than that associated with active or at-rest conditions. In this regard, the contractor should take appropriate precautions during the backfill placement. ' TEMPORARY SLOPES For the excavation of the basement, foundations and utility trenches, temporary vertical cut~ to a maximum height of 4 feet may be constructed in natural soils. Any temporary cuts beyond the above height constraints should be shored or further laid back following a 1: 1 (horizontal to vertical) !slope ratio. OSHA guidelines for trench excavation safety should be implemented during constructionJ Based on the consistency of the bedrock material and setbacks to adjacent residences, it i~ our opinion that the proposed development will not have an adverse effect on the off-site frontag~ area and adjacent properties provided temporary slopes are excavated in accordance with OSHA guidelines. TRENCH BACKFILL Excavations for utility lines, which extend under structural areas should be properly backfilled and compacted. Utilities should be bedded and backfilled with clean sand or approved granular s~il to a depth of at least one foot over the pipe. This backfill should be uniformly watereq and compacted to a firm condition for pipe support. The remainder of the backfill should be op-site soils or non-expansive imported soils, which should be placed in thin lifts, moisture-conditf oned and compacted to at least 90% relative compaction. · DRAINAGE Adequate measures should be undertaken after the structure and other improvements are in ])lace, such that the drainage water within the site and adjacent properties is directed away frorp the foundations, footings, floor slabs and the tops of slopes via rain gutters, downspouts, surface srVales and subsurface drains towards the natural drainage for this area. A minimum gradient of 2 percent I is recommended in hardscape areas. In earth areas, a minimum gradient of 5 percent away frofll the I 10 KEN & SANDRA BAPTIEICARLSBAD BOULEVARD PROJECT NO.16-1126F2 structure for a distance of at least 10 feet should be provided. If this requirement cannot be m~t due to site limitations, drainage can be done through a swale in accordance with Section 1804.3 Qf the 2013 California Building Code. Earth swales should have a minimum gradient of 2 pefcent. Drainage should be directed to approved drainage facilities. Proper surface and subs¥ace drainage will be required to minimize the potential of water seeking the level of the bearing! soils under the foundations, footings and floor slabs, which may otherwise result in undermining and differential settlement of the structure and other improvements. FOUNDATION PLAN REVIEW Our firm should review the foundation plans during the design phase to assure conformance with the intent of this report. During construction, foundation excavations should be observed by our representative prior to the placement of forms, reinforcement or concrete for conformance wi~h the plans and specifications. · LIMITATIONS OF INVESTIGATION Our investigation was performed using the skill and degree of care ordinarily exercised, under sibiilar circumstances, by reputable soils engineers and geologists practicing in this or similar localitie~. No other warranty, expressed or implied, is made as to the conclusions and professional advice inclucj.ed in this report. This report is prepared for the sole use of our client and may not be assigned to ~thers without the written consent of the client and ECSC&E, Inc. · The samples collected and used for testing, and the observations made, are believed representati~e of site conditions; however, soil and geologic conditions can vary significantly between explo~ation trenches, boreholes and surface exposures. As in most major projects, conditions reveal~d by construction excavations may vary with preliminary findings. If this occurs, the changed condjtions must be evaluated by a representative of ECSC&E and designs adjusted as required or alt~mate designs recommended. This report is issued with the understanding that it is the responsibility of the owner, or of his representative to ensure that the information and recommendations contained herein are brought to the attention of the project architect and engineer. Appropriate recommendations should be incorptjrated into the structural plans. The necessary steps should be taken to see that the contractor and subcontractors carry out such recommendations in the field. The findings of this report are valid as of this present date. However, changes in the condition$ of a property can occur with the passage of time, whether they are due to natural processes or the wotks of man on this or adjacent properties. In addition, changes in applicable or appropriate standard~ may occur from legislation or the broadening of knowledge. Accordingly, the findings of this repo~ may be invalidated wholly or partially by changes outside of our control. Therefore, this report is subjFct to review and should be updated after a period of two years. 11 KEN & SANDRA BAPTIEI CARLSBAD BOULEVARD PROJECT NO. 16-J 126F2 ADDITIONAL SERVICES The review of plans and specifications, field observations and testing under our direction are integral parts of the recommendations made in this report. If East County Soil Consultation and Enginehing, Inc. is not retained for these services, the client agrees to assume our responsibility for any pot~ntial claims that may arise during construction. Observation and testing are additional services, whitjh are provided by our firm, and should be budgeted within the cost of development. · Plates No. 1 through 3, Page L-1 and References are parts of this report. 12 .. ·~ I . I At1 f ~ I ii · I ~ 1----' G.~yJ 41- ~ -& .. ,. _, l~/LLJ.._ f:T71,,17""v ;T!!_ ~~ ~-~-1/-. --J ~ / ' /P.!>/!J, //,'€/Q5 /~ . L: . . ,.;~ ( . e~'1'.l lf!Z =!!r) 'f ./.i,i, hieit~,~ l(t. Al'll'-ty~~ C£o:>'57-7Ez:::170N' A-,1 r /;"" .. ~ ;i'-:5tJ; ¢if ~ , r-----1 J I ~ t ~ f(l I ) I~ ~:!1~· . l~~/k ?I" t=f;i"o --:~ ,£ ~ }OES{u;?!~ ~ ~PD /Ir~~ C.£,CJ55,-~77t?/II tJ-/5 ~ jJ/-;,r~I ~-~ ~ ..... T ..aL .,-.... ~._.... .... .. :_-c~:-r:,.-: ...... 1..:r :>II ......... ~~:i" .... T.--...c_r r #. · . ' • <; ... ~ R •XI ,h/!H-/ . \Il-q," .'I.I .,, I I·--. l I ' . fP==Ff' ••.: . ~ I ~~•1•·-...:..I I~... . ""''-- ~ ~ \) , __ 1_0• ~ ~ ...,,1_c• 111-.. ... _., ,-."f .•. ~. ~ • :/=Y.:FWl?AT!J~f c:L),fel/Pl,6. t;5t1/ ~~I/ {rt ~ l:db5!75 -------. ---·-·---·-·-------··- EAST COUNTY SOIL CONSULTATION & ENGINEERING, INC. 10925 HAR1LEY RD., SUITE I. SANTEE. CA 92071 ~C / ~/VIC'A£ ~~ ,., ~ ~ /1&2t)' ~ r ~~ ~£ ,Mq/E£t ~·~ ~z. ~6 "vr/Y(J, /l-//Z6F2-P4'r7E KO-/ DEPTH Surface 1.0' 1.5 2.0' 2.5' 3.0' 3.5' 5.0' KEN & SANDRA BAPTIEI CARLSBAD BOULEVARD PROJECT NO. l 6-l l 26F2 PLATENO.2 SUMMARY SHEET BOREHOLE NO. 1 SOIL DESCRIPTION TOPSOIL dark brown, moist, loose, porous, silty sand with rootlets " " " " " " SLOPEW ASH (Qsw) light brown, dry to moist, loose, silty sand " " " " " TERRACE DEPOSITS (Qt) reddish brown, moist, medium dense, silty sand becomes dense " " " " " bottom of borehole, no caving, no groundwater borehole backfilled 1/14/16 " y ---------------------------------------------- DEPTH Surface 1.5 2.5' 3.0' 5.0' DEPTH Surface 1.5 2.5' 3.0' 10.0' BOREHOLE NO. 2 SOIL DESCRIPTION TOPSOIL dark brown, moist, loose, porous, silty sand with rootlets SLOPEWASH (Qsw) light brown, moist, loose, silty sand TERRACE DEPOSITS (Qt) reddish brown, moist, medium dense, silty sand becomes dense bottom of borehole, no caving, no groundwater borehole backfilled 1/14/16 y 111.3 122.2 -------------------------- BOREHOLE NO. 3 SOIL DESCRIPTION TOPSOIL dark brown, moist, loose, porous, silty sand with rootlets SLOPEWASH (Qsw) light brown, moist, loose, silty sand TERRACE DEPOSITS (Qt) reddish brown, moist, medium dense, silty sand becomes dense bottom of borehole, no caving, no groundwater borehole backfilled 1/14/16 y --------------------------------------------------------------------------- Y = DRY DENSITY IN PCF M = MOISTURE CONTENT JN % 13 M 8.4 4.8 4.2 M 7.2 5.3 M ... . . • INITIAL MOISTURE CONTENT(¾) 8.8 l" 1/2" 3/8" #4 #8 #16 #30 #50 #100 #200 uses KEN & SANDRA BAPTIEICA RLSBAD BOULEVARD PROJECT NO.16-1126F2 PAGE L-1 LABORATORY TEST RESULTS EXPANSION INDEX TEST {ASTM D4829) SATURATED MOISTURE CONTENT{¾) 15.9 INITIAL DRY DENSITY EXPANSION {PCF) INDEX 110.1 5 PARTICLE SIZE ANALYSIS (ASTM D422) Percent Passing BH-1@ 1.0' To soil 100 99 99 91 44 20 13 SM 14 Percent Passing BH-1@2.0' Slo wash 100 91 41 20 14 SM LOCATION BH-1 @ 3.5' Percent Passing Bl{-1@3.5' Ten-ace . 100 93 44 19 13 SM ,· .. .. •• KEN & SANDRA BAPTIEICARLSBADBOULEVARDPROJECTNO. /6-J/26F2 REFERENCES I. "2013 California Building Code, California Code of Regulations, Title 24, Part 2, Volume 2 of 2", Published by International Code Council. 2. "Geologic Map of the San Diego 30' x 60' Quadrangle, California", by Michael P. Kennedy and Siang S. Tan, 2008. 3. "Geotechnical and Foundation Engineering: Design and Construction", by Robert W. Day, 1999. 4. "Geologic ,N,'laps.; ,of the,1Northwestern Part of San Diego County, California", Department of Conservation, Division o/Mines and Geology, by Siang S. Tan and Michael P. Kennedy, 1996. 5. "Bearing Capacity of Soils, Technical Engineering and Design Guides as Adapted from the US Army Corps of Engineers, No. 7", Published by ASCE Press, 1994. 6. "Foundations and Earth Structures, Design Manual 7 .2", by Department of Navy Naval Facilities Engineering Command, May 1982, Revalidated by Change 1 September 1986. 7. "Ground Motions and Soil Liquefaction during Earthquakes", by H.B. Seed and 1.M. Idriss, 1982. 15