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Home My WebLink AboutSP 181H; Home2 Carlsbad Suites; UPDATE GEOTECHNICAL RECONNAISSANCE; 2015-07-14'~ i f~Sii Geotechnical Exploration, Inc. SOIL AND FOUNDATION ENGINEERING • GROUNDWATER e ENGINEERING GEOLOGY 04 March 2016 Royal Hospitality Carlsbad, LLC P .0. Box· 3872 Rancho Santa· Fe, CA 92067 Attn: Mr. Koong Cho Subject: Response to City Review Comments Proposed Carlsbad Home 2 Suites 1901 Wright Place, APN 212-091-13-00 Carlsbad, California Dear Mr. Cho: Job No. 05-9085 In accordance with the request of your civil engineer, we are responding to comments/questions made by the City reviewer for the subject project. We previously performed a geotechnical investigation for a previously planned project at the site, the results of which were presented in our report titled "Report of Preliminary Geotechnical Investigation, Carlsbad Airport Center," dated April 14, 2006. In addition, we also performed an update geotechnical reconnaissance for the currently planned project, the results of which were presented in our report dated July 14, 2015. Our comments are presented below. 1. Based on the results of our previous investigation, it is our opinion that the site is not suitable for infiltration of water due to the clayey nature of the on- site soils. Further, it is our opinion that any attempt at infiltration into the potentially expansive soils would most likely result in damage to the proposed improvements. 2. With regard to the proposed BMP-4, a gravel detention facility beneath AC pavement, the gravel will consist of Caltrans Class 2 Permeable Material which will provide adequate pavement support provided th~ permeable material is compacted with a vibratory compactor in lifts not exceeding 8 Inches in thickness. 3. In design of the retaining walls for BMPs 1 and 2, the design engineer needs to consider hydrostatic forces which will develop when the basins are flooded during storm events. In addition, full passive resistance for the outboard 7420 lRADE STREET• SAN DIEGO, CA. 92121 e (858) 549·7222 e FAX: (858) 549-1604 e EMAIL: geotech@gel-sd.com I~ Proposed Carlsbad Home 2 Suites Carlsbad, California Job No. 05-9085 Page 2 walls should be reduced as needed as indicted in our 2006 investigation report. This opportunity to be of continued service is sincerely appreciated. If you have any questions, please contact our office. Reference to our Job No. 05-9085 will help to expedite a response to your inquiries. Respectfully submitted, GEOTECHNICAL EXPLORATION, INC. ~.f!i:696 Senior Geotechnical Engineer Ge technical Exploration, Inc. SOIL AND FOUNDATION ENGINEERING • GROUNDWATER • ENGINEERING GEOLOGY 14 July 2015 Royal Hospitality, LLC P.O. Box 3872 Rancho Santa Fe, CA 92067 Attn: Mr. Koong Cho Subject: Update Geotechnical Reconnaissance Proposed Carlsbad Home 2 Suites 1901 Wright Place, APN 212-091-13-00 Carlsbad, California Dear Mr. Cho: ·i ··: ' : ' ~· '"' \. Job No. 05-9085 In accordance with your request, Geotechnical Exploration, Inc. has performed an update geotechnical reconnaissance for the subject project. We previously performed a geotechnical investigation for a previous project at the site, the results of which were presented in our report titled "Report of Preliminary Geotechnical Investigation, Carlsbad Airport Center," dated April 14, 2006. Our scope of services for this update reconnaissance included review of our previous work at the site as well as the current development plan, a site reconnaissance, and the preparation of this update report addressing the applicability of the recommendations in our 2006 report to the current project as well as the presentation of revised/supplemental recommendations as warranted. Based on our review of the current project plans provided us, the currently proposed development of the site will consist of a 3-story hotel complex. Based on our site reconnaissance on July 10, 2015, the site appears to be essentially unchanged from the time of our previous investigation. Accordingly, it is our 7420 TRADE STREEfil SAN DIEGO, CA. 92121 • (858) 549-7222 <9 FAX: (858) 549-1604 e EMAIL: geotech@gei-sd.com Proposed Carlsbad Home 2 Suites Carlsbad1 California Job No. 05-9085 Page 2 opinion that the conclusions and recommendations presented in our April 14, 2006, investigation report remain applicable with the exception of updated slab vapor barrier recommendations and that the presently proposed structures will be designed in accordance with the 2013 California Building Code. Updated vapor barrier and seismic design parameters are presented below. 1. Updated Slab Vapor Barrier Recommendations: We recommend that the vapor barrier for floor slabs consist of a minimum 15-mil extruded polyolefin plastic (no recycled content or woven materials permitted). Permeance as tested before and after mandatory conditioning (ASTM E1745 Section 7.1 and sub-paragraphs 7.1.1-7.1.5) should be less than 0.01 perms (grains/square foot/hour in Hg) and comply with the ASTM E1745 Class A requirements. Installation of vapor barriers should be in accordance with ASTM E1643. The basis of design is 15-mil StegoWrap vapor barrier placed per the ~ -' ,, ' manufacturer's guidelines. Reef Industries Vapor Guard membrane has also 11 2. been shown to achieve a permeance of less than 0.01 perms. We also L' recommend that the slabs be poured directly on the vapor barrier which is , placed directly on the finished slab subgrade surface; no sand layers are utilized. Seismic Design Criteria: Site-specific seismic design criteria for the proposed structures are presented in the following table in accordance with Section 1613 of the 2013 CBC, which incorporates by reference ASCE 7-10 for seismic design. We have determined the mapped spectral acceleration values for the site, based on a latitude of 33.1209 degrees and longitude of -117.2892 degrees, utilizing a tool provided by the USGS, which provides a solution for ASCE 7-10 (Section 1613 of the 2013 CBC) utilizing digitized files ("~ ~\ L_' ,---. L__j ' ' ~-, L___, ,_ __ j . ___ ') Proposed Carlsbad Home 2 Suites Carlsbad, California Job No. 05-9085 Page 3 for the Spectral Acceleration maps. In addition, we have assigned a Site Soil Classification of Sc. TABLE I Mapped Spectral Acceleration Values and Design Parameters In addition, the 2013 CBC requires that retaining walls 6 feet or more in height be designed to resist seismic loads. For seismic design of unrestrained walls, if required, we recommend that the seismic pressure increment be taken as a fluid pressure distribution utilizing an equivalent fluid weight of 12 pcf. For restrained walls we recommend that the seismic pressure increment be taken as a fluid pressure distribution utilizing an equivalent fluid weight of 18 pcf added to the active static fluid pressure utilizing an equivalent fluid weight of 35 pcf. LIMITATIONS Our services consist of professional opinions and recommendations made in accordance with generally accepted geotechnical engineering principles and practices. This warranty is in lieu of all other warranties either expressed or implied . Proposed Carlsbad Home 2 Suites Carlsbad, California Job No. 05-9085 Page 4 This opportunity to be of service is sincerely appreciated. If you have any questions/ please contact our office. Reference to our lob No. 05-9085 will help to expedite a response to your inquiries. Respectfully submitted, GEOTECHNICAL EXPLORATION, INC. :.:H~~ Senior Geotechnical Engineer L_J r: L _ _i L_} c-' , I L_, \ _ _', REPORT OF PRELIMINARY GEOTECHNICAL . Carlsbad Airport Center SE Corner of Wright Place and Palomar Oaks Way Carlsbad, California JOB NO. 05-9085 14 April 2006 Prepared for: AKC San Diego, LLC GEOTECHNICAL EXPLORATION, INC. SOIL & FOUNDATION ENGINEERING • GROUNDWATER HAZARDOUS MATERIALS MANAGEMENT • ENGINEERING GEOLOGY 14 April 2006 AKC San Diego, LLC cjo McArdle Associates Architects 5838 Edison Place, Suite 100 Carlsbad,CA 92008 Attn: Ms. Kay Willis Subject: Gentlemen: Report of Preliminary Geotechnical Carlsbad Airport Center SE Corner of Wright Place and Palomar Oaks Way Carlsbad, California lob No. 05-9085 In accordance with your request, and our signed proposal of September 12, 2005, Geotechnical Exploration, Inc. has performed a preliminary geotechnical investigation for the subject project in Carlsbad, California. The fieldwork was performed on November 22, 2005. If the conclusions and recommendations presented in this report are incorporated into the design and construction of the proposed development, it is our opinion that the site is suitable for the project. This opportunity to be of service is sincerely appreciated. Should you have any questions concerning the following report, please do not hesitate to contact us. Reference to our Job No. 05-9085 will expedite a response to your inquiries. Respectfully submitted, GEOTECHNICAL EXPLORATION, INC. Wm. D. Hespelef,' G.E. 396 . Senior Geotechnical Engineer 7420TRADE STREET • SAN DIEGO, CA 92121 • (858) 549-7222 • FAX: (858) 549-1604 • E-MAIL: geotech@lxpres.com \__) ~__i ~ --i ',, TABLE OF CONTENTS PAGE I. PROJECT SUMMARY AND SCOPE OF SERVICES 1 II. SITE DESCRIPTION 2 III. FIELD INVESTIGATION 3 IV. SOIL DESCRIPTION 4 ~--_j v GROUNDWATER 9 VI. SEISMIC CONSIDERATIONS 10 VII. LABORATORY TESTS AND SOIL INFORMATION 14 VIII. CONCLUSION AND RECOMMENDATIONS 16 IX. GRADING NOTES 24 X. LIMITATIONS 25 FIGURES I. Vicinity Map II. Site Plan III. 1990 As-Built Grading Plan Excerpt IVa-I. Exploratory Boring Logs Va-c Laboratory Data APPENDICES A. Unified Soil Classification System REPORT OF PRELIMINARY GEOTECHNICAL Carlsbad Airport Center SE Corner of Wright Place and Palomar Oaks Way Carlsbad, California lob No. 05-9085 The following report presents the findings and recommendations of Geotechnical Exploration, Inc. for the subject project (for project location see Figure No. I). I. PROJECT SUMMARY AND SCOPE OF SERVICES It is our understanding, based on a recently received grading plan provided by McArdle Associates Architects titled "Carlsbad Airport Center," that the subject development will consist of 6 one and two-story office buildings and associated paved parking and drives (for Site Plan, refer to Figure No. II). Based on our review of the grading plan, grading at the site will generally consist of cuts and fills of up to about 4 feet deep to attain the desired finish grades. In addition, restrained retaining/building walls up to about 10 feet high will be constructed for buildings D and E and unrestrained site retaining walls up to about 8 feet high will be constructed along the eastern portion of the northern property boundary and along the entire eastern boundary. The scope of work performed for this investigation included review of the proposed grading and development plans (see Figure No. II), research at the City of Carlsbad regarding previous grading at the site, a site reconnaissance and subsurface exploration program, laboratory testing, geotechnical engineering analysis of the field and laboratory data, and the preparation of this report. The data obtained and the analyses performed were for the purpose of providing design and construction criteria for the project earthwork, building foundations, slab-on-grade floors, retaining walls, and pavements. n , __ j ( __ .1 _, l Carlsbad Airport Center Carlsbad, California II. SITE DESCRIPTION Job No. 05-9085 Page 2 The site is a rectangular-shaped parcel with a plan area of about 3.85 acres. In general, the area of the proposed structures is a relatively flat, previously graded lot, sloping down toward the south, with ground surface elevations varying from about +171 MSL at the northwest corner to about + 161 at the southeast corner. The site is bounded by an existing cut and fill slope along the eastern property boundary that descends from the adjacent property, existing cut and fill slopes along the southerly boundary that descend to Palomar Airport Road, and an existing cut slope along the westerly boundary descending to Palomar Oaks Way. Surface vegetation on the graded pad in general consists of a light growth of low weeds. The slopes surrounding the site are heavily landscaped with groundcover, shrubs and trees. From our research at the City of Carlsbad we obtained a copy of an as-built grading plan by Rick Engineering Company titled "Grading Plans for C.T. 81-46 Unit No. 1, Carlsbad, California, Sheet 5 of 11" dated January 22, 1990, that pertains to the previous grading at the site (Lot 12). In addition, we obtained a copy of an as-built geotechnical report by Moore & Taber that pertains to the site, dated February 25, 1987. Based on our review of the as-built information, the previous grading of the site consisted mostly of cuts into formational material. The southeast portion of the site, however, received fills up to about 20 feet deep. In addition, the southern portion of the slope along the eastern boundary of the site, which descends from the developed property to the east, is comprised of existing fill soils. The eastern portion of the slope along the southern boundary, which descends to Palomar Airport Road, is also comprised of existing fill soils. An excerpt from the as-built grading plan showing Lot 12 is presented on Figure No. III. Carlsbad Airport Center Carlsbad, California III. FIELD INVESTIGATION Job No. 05-9085 Page 3 The field investigation consisted of a surface reconnaissance and a subsurface exploration program utilizing a truck-mounted, continuous-flight auger drill rig. Twelve exploratory borings were drilled across the site on November 22, 2005, to depths of 3.5 to 20 feet. The soils encountered in the borings were continuously logged in the field by our representative and described in accordance with the Unified Soil Classification System (Refer to Appendix A). The approximate locations of the borings are shown on Figure No. II. Representative samples were obtained from the exploratory borings at selected depths appropriate to the investigation. All samples were returned to our laboratory for evaluation and testing. Standard penetration resistance blow counts were obtained by driving a 2-inch O.D. split spoon sampler with a 140-pound hammer dropping through a 30-inch free fall. The sampler was driven a maximum of 18 inches and the number of blows for each 6-inch interval was recorded. The blows per foot indicated on the boring logs represent the accumulated number of blows that were required to drive the last 12 inches or portion thereof. Samples contained in liners were recovered by driving a 3.0-inch O.D. California sampler 18 inches into the soil using a 140-pound hammer. Boring logs have been prepared on the basis of our observations and laboratory test results. Logs of the borings are attached as Figure No. IV. The following chart provides an in-house correlation between the number of blows and the relative density of the soil for the Standard Penetration Test and the 3-inch sampler. L __ } .!._.J \ ___ ) ~ ---} Carlsbad Airport Center Carlsbad, California DENSITY SOIL DESIGNATION Sand and ·Very loose Nonplastic Silt Loose Medium Dense Very Dense Clay and Very soft Plastic Silt Soft Firm Stiff Very stiff Hard Very Hard 2-INCH O.D. SAMPLER BLOWS/FOOT 0-4 5-10 11-30 31-50 Over 50 0-2 3-4 5-8 9-15 16-30 31-60 Over 60 IV. SOIL DESCRIPTION Job No. 05-9085 Page 4 3-INCH O.D. SAMPLER BLOWS/FOOT 0-7 8-20 21-53 54-98 Over 98 0-2 3-4 5-9 10-18 19-45 46-90 Over 90 Existing fill soils consisting of medium dense silty and clayey sands and stiff sandy clays were encountered in Borings 1 through 6 to depths of 6 to 20 feet. In Borings 1, 3, 5, and 6, the fill soils were underlain by medium dense to dense, natural silty sands of the Del Mar Formation at depths of 6 to 17.5 feet. In Borings 7 through 10 and 12, very stiff to hard natural silty clays of the Del Mar Formation were encountered from the ground surface to depths of 2.0 to 3.5 feet. In Boring 10 and 12, the clays were underlain by very dense silty sands. Very dense formational silty sands were encountered in Boring 11 from the ground surface to the depth explored. Based on the boring results and our laboratory testing, the existing fill soils encountered in the borings appear to be in a less than uniformly well compacted condition. Based on our laboratory testing, the clayey sand existing fill soils and formational clays encountered have a high potential for expansion. The boring logs and related information depict subsurface conditions only at the specific locations shown on the site plan and on the particular date designated on ca·rlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 5 the logs. Subsurface conditions at other locations may differ from conditions occurring at these boring locations. Also, the passage of time may result in changes in the subsurface conditions due to environmental changes. V. GROUNDWATER No groundwater was encountered during the course of our field investigation and we do not anticipate significant groundwater problems to develop in the future if the property is developed as proposed and proper drainage is maintained. It should be kept in mind, however, that any required grading operations may change surface drainage patterns and/or reduce permeabilities due to the densification of compacted soils. Such changes of surface and subsurface hydrologic conditions, plus irrigation of landscaping or significant increases in rainfall, may result in the appearance of surface or near-surface water at locations where none existed previously. The appearance of such water is expected to be localized and cosmetic in nature, if good positive drainage is implemented, as recommended in this report, during and at the completion of construction. On properties such as the subject site where dense, low permeability soils and/or formational materials exist at shallow depths/ even normal landscape irrigation practices or periods of extended rainfall can result in shallow "perched" water conditions. The perching (shallow depth) accumulation of water on a low permeability surface can result in areas of persistent wetting and drowning of lawns, plants and trees. Resolution of such conditions, should they occur, may require site-specific design and construction of subdrain and shallow "wick" drain dewatering systems. n r----, \ J t _) '_j Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 6 It must be understood that unless discovered during initial site exploration or encountered during site grading operations, it is extremely difficult to predict if or where perched or true groundwater conditions may appear in the future. When site fill or formational soils are fine-grained and of low permeability, water problems may not become apparent for extended periods of time. Water conditions, where suspected or encountered during construction, should be evaluated and remedied by the project civil and geotechnical consultants. The project developer and homeowner, however, must realize that post-construction appearances of groundwater may have to be dealt with on a site-specific basis. VI. SEISMIC CONSIDERATIONS The San Diego area, as most of California, is located in a seismically active region. The San Diego area has been referred to as the eastern edge of the Southern California Continental Borderland, an extension of the Peninsular Ranges Geomorphic Province. The borderland is part of a broad tectonic boundary between the North American and Pacific Plates. The plate boundary is dominated by a complex system of active major strike-slip (right lateral)1 northwest-trending faults extending from the San Andreas Fault about 70 miles east, to the San Clemente Fault/ about 50 miles west of the San Diego metropolitan area. Based on a review of some available published information, including the County of San Diego Faults and Epicenters Map, there are no faults known to pass through the site. The prominent fault zones generally considered having the most potential for earthquake damage in the vicinity of the site are the active Rose Canyon Fault Zone mapped approximately 4 miles west-southwest of the site1 and the active Elsinore and San Jacinto Fault zones, mapped approximately 40 and 63 miles northeast of the site, respectively. Carlsbad Airport Center Carlsbad1 California Job No. 05-9085 Page 7 Although research on earthquake prediction has greatly increased in recent years, geologists and seismologists have not yet reached the point where they can predict when and where an -earthquake will occur. Nevertheless! on the basis of current technology, it is reasonable to assume that the proposed buildings may be subject to the effects of at least one moderate to major earthquake during their design lives. During such an earthquake, the danger from fault offset through the site is remoter but relatively strong ground shaking is likely to occur. Strong ground shaking not only can cause structures to shake, but it also has the potential for including other phenomena that can indirectly cause substantial ground movements or other hazards resulting in damage to structures. These phenomena include seismically induced waves such as tsunamis and seiches, inundation due to dam or embankment failure, soil liquefaction, landsliding, lateral spreading, differential compaction and ground cracking. Available information indicates that the location of and geotechnical conditions at the site are not conducive to any of these phenomena. VII. LABORATORY TESTS AND SOIL INFORMATION Laboratory tests were performed on disturbed and relatively undisturbed soil samples in order to evaluate their index, strength, expansion, compactness, and compressibility properties. The following tests were conducted on the sampled soils: ' ' \_ ___ .: L) l __ ; L _ _~ \. i ·~. ' '--j ca·rlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 8 1. Laboratory Compaction Characteristics (ASTM D1557-98 2. Density Tests (from relatively undisturbed boring samples) 3. Determination of Percentage of Particles Smaller than No. 200 Sieve (ASTM D 1140-97) 4. Direct Shear Test (ASTM D 3080-98) 5. Expansion Index (ASTM D 4829-95) Laboratory compaction tests establish the laboratory maximum dry density and optimum moisture content of the tested soils. This test was used to aid in evaluating the existing fill soils at the site, as well as the anticipated properties of new structural fills. Laboratory density tests on samples of the existing fills encountered were performed to aid in evaluating the compactness of the existing fills encountered in the borings. The particle size smaller than a No. 200 sieve analysis aids in classifying the tested soils in accordance with the Unified Soil Classification System and provide qualitative information related to engineering characteristics such as expansion potential, permeability, and shear strength. Laboratory direct shear tests aid in evaluating the strength properties of the on-site soils. The expansion potential of soils is determined, when necessary, utilizing the Standard Test Method for Expansion Index of Soils (ASTM D 4829-95). In accordance with the Standard, potentially expansive soils are classified as follows; Carlsbad Airport Center Carlsbad, California EXPANSION INDEX 0 to 20 21 to 50 51 to 90 91 to 130 Above 130 Job No. 05-9085 Page 9 POTENTIAL EXPANSION Very low Low Medium Hiqh Very hiqh Based on the test results, the clayey sand existing fill soils and clay formational materials possess a high expansion potential, with measured expansion index values of 97 and 1011 respectively. The laboratory test results are shown on the borings logs and on Figure Nos. Va-c . VIII. CONCLUSIONS AND RECOMMENDATIONS The following conclusions and recommendations are based on the field investigation conducted by our firm, our laboratory test results, and our experience with similar soils and formational materials. The primary features of concern at the site are the less than uniformly well-compacted condition of the existing fill soils at the site and the high expansion potential of the clayey existing fill soils and the natural, formational clays. In order to preclude the possibility of excessive settlement damage to the proposed buildings it will be necessary to remove and recompact any existing fill soils that are present in building areas. In order to minimize possible damage to the structures resulting from swelling and shrinkage of the potentially expansive on-site materials, the buildings must be supported on footings that extend deeper than would normally be recommended and the building floor slabs, as well as exterior slabs, should be supported on a layer of low-expansion potential imported fill material. Grading and foundation recommendations are presented in the following sections. l_; I\ :~ _) LJ r-1 _;,. --_, : __ _j I_) ~ --] Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 10 The opinions, conclusions and recommendations presented in this report are contingent upon Geotechnical Exploration, Inc. being retained to review the final plans and specifications as they are developed and to observe the site earthwork and installation of foundations. A. Preparation of Soils for Site Development 1. Clearing and Stripping: The area of the site to be graded should be cleared of any miscellaneous trash or debris that may be present at the time of construction and stripped of all vegetation. The cleared and stripped materials should be properly disposed of off-site. 2. Treatment of Existing Fill Soils: In order to provide suitable support for the proposed buildings, we recommend that any existing fill soils in the new building areas be removed and recompacted. The recompaction work should consist of (a) removing all existing fill soils down to undisturbed formational materials within and 10 feet beyond the building limits; (b) scarifying, moisture conditioning, and compacting the exposed subgrade soils; and (c) replacing the fill materials as compacted structural fill. The areal extent and depth required to remove the fill soils should be determined by our representatives during the excavation work based on their examination of the soils being exposed. Any unsuitable materials (such as oversize rubble and/or organic matter) should be selectively removed as directed by our representative and disposed of off-site. 3. Subgrade Preparation: After the site has been cleared, stripped, and the required excavations made, the exposed subgrade soils in those areas-to receive fill, building improvements and/or pavements should be scarified to a depth of 6 inches1 moisture conditioned1 and compacted to the requirements Carlsbad Airport Center Carlsbad1 California Job No. 05-9085 Page 11 of Recommendation No. 61 "Compaction." Potentially expansive clayey soils with an Expansion Index greater than 401 that are exposed at the finished subgrade level. in cut areas where buildings and/or exterior slabs-on-grade are to be constructed, should be removed and replaced with compacted low- expansion potential (Expansion Index of 20 to 40) fill so as to provide an 18-inch minimum thickness of low-expansion potential soil at the subgrade level. The depth and areal extent of the required removals should be determined by our representative at the time of construction based on an examination of the soils exposed. 4. Low Expansion Potential Imported Fill Laver: Because of the high expansion potential of the clayey, on-site, near-surface soils, we recommend that building floor slabs and exterior slabs-on-grade be supported on an 18-inch minimum thickness of low-expansion potential (Expansion Index of 20 to 40 per ASTM 04829-98) imported soil. In cut areas, this will require that the clayey soils be undercut and replaced with an 18-inch thickness of compacted low-expansion potential fill. Similarly, in fill areas the upper 18 inches of the finish subgrade soils should be a compacted low-expansion potential soil. The low-expansion potential soil layer should extend a minimum of 5 feet beyond the perimeter limits of the proposed building areas and all exterior slabs-on-grade. 5. Material for Fill: All existing on-site soils with an organic content of less than 3 percent by volume are, in general, suitable for use as fill except where a low-expansion potential layer is required. Imported fill materia~ should be a low-expansion potential (Expansion Index of 20 to 40 per ASTM 04829-,98)1 granular soil with a plasticity index of 12 or less. In addition, imported· fill materials should not contain rocks or lumps more than 3 inches in greatest dimension, not more than 15 percent larger than 1 inch, and no more than LJ (__) ! _I L) r-. I -_j <- ' __ i Ca"rlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 12 6. 25 percent of the fill should be larger than Y4-inch. All materials for use as fill should be approved by our representative prior to filling. Fill Compaction: All structural fill should be compacted to a minimum degree of compaction of 90 percent based upon ASTM 01557-98. The upper 6 inches of subgrade soil beneath pavements should be scarified, moisture conditioned, and compacted to a minimum degree of compaction of 95 percent just prior to placement of the aggregate base layer. Fill material should be spread and compacted in uniform horizontal lifts not exceeding 8 inches in uncompacted thickness. Before compaction begins, the fill should be brought to a water content that will permit proper compaction by either: (1) aerating the fill if it is too wet, or (2) moistening the fill with water if it is too dry. All on-site clayey soils should be compacted at a moisture content at least 2 percent above the laboratory optimum. The required moisture content should be maintained until the placement of capping material or pavement base is completed. Each lift should be thoroughly mixed before compaction to ensure a uniform distribution of moisture. 7. Permanent Slopes: We recommend that any required permanent cut and fill slopes be constructed to an inclination no steeper than 2 to 1 (horizontal to vertical). The project plans and specifications should contain all necessary design features and construction requirements to prevent erosion of the on- site soils both during and after construction. Slopes and other exposed ground surfaces should be appropriately planted with a protective ground cover. Fill slopes should be constructed to assure that the recommended minimum degree of compaction is attained out to the finished slope face. This may be accomplished by "backrolling" with a sheepsfoot roller or other suitable Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 13 8. equipment as the fill is raised. Placement of fill near the tops of slopes should be carried out in such a manner as to assure that loose, uncompacted soils are not sloughed over the tops and allowed to accumulate on the slope face. Temporarv Slopes: Based on our subsurface investigation work, laboratory test results, and engineering analysis, temporary cut-slopes for construction of the proposed retaining walls should be safe against mass instability at an inclination of 1 (horizontal) to 1 (vertical). Temporary slopes along the east property boundary, however, should not start closer than 5 feet horizontally from the existing retaining wall on the adjacent property. In addition, some localized sloughing or ravelling of the soils exposed on the slopes may occur. Since the stability of temporary construction slopes will depend largely on the contractor's activities and safety precautions (storage and equipment loadings near the tops of cut-slopes, surface drainage provisions, etc.) it should be the contractor's responsibility to establish and maintain all temporary construction slopes at a safe inclination appropriate to his methods of operation. 9. Trench and Retaining Wall Backfill: All backfill soils placed in utility trenches or behind retaining walls should be compacted to a minimum degree of compaction of 90 percent. Backfill material should be placed in lift thicknesses appropriate to the type of compaction equipment utilized and compacted to a minimum degree of 90 percent by mechanical means. In pavement areas, that portion of the trench backfill within the pavement section should conform to the material and compaction requirements of the adjacent pavement section. In addition, the integrity of the low-expansion potential fill layer should be maintained in utility trench backfills within building and exterior slab areas. Around perimeter footings, trench backfill L_i u l_ j L .. i l_~j !i !l I ' ~--~ Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 14 beneath the level of the low-expansion fill layer should consist of on-site clayey materials in order to minimize the potential for migration of water below the perimeter footings at the trench locations. Our experience has shown that even shallow, narrow trenches, such as for irrigation and electrical lines, that are not properly compacted can result in problems, particularly with respect to shallow ground water accumulation and migration. 10. Surface Drainage: Positive surface gradients should be provided adjacent to the buildings, and roof gutters and downspouts should be installed so as to direct water away from foundations and slabs toward suitable discharge facilities. Ponding of surface water should not be allowed anywhere on the site. Appropriate erosion control measures should be taken at all times during and after construction to prevent surface runoff waters from entering footing excavations or ponding on finished building pad areas. B. Design Parameters for Proposed Foundations 11. Footings: We recommend that the proposed office buildings be supported on conventional, individual-spread and/or continuous footing foundations bearing on undisturbed formational material and/or well compacted fill material. All footings should be founded at least 24 inches below the lowest adjacent finished grade or 6 inches below the bottom of the low-expansion potential cap, whichever is lower. Footings located adjacent to the tops· of slopes should be extended sufficiently deep so as to provide at least 10 feet of horizontal cover or 1¥2 times the width of the footing, whichever is Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 15 greater, between the slope face and outside edge of the footing at the footing bearing level. Footings located adjacent to utility trenches should have their bearing surfaces situated below an imaginary 1.5 to 1 plane projected upward from the bottom edge of the adjacent utility trench. At the recommended depths, footings may be designed for allowable bearing pressures of 3,000 pounds per square foot (psf) for combined dead and live loads and 4,000 psf for all loads, including wind or seismic. The footings should, however, have a minimum width of 12 inches. All continuous footings should contain top and bottom reinforcement to provide structural continuity and to permit spanning of local irregularities. We recommend that a minimum of two No. 5 top and two No. 5 bottom reinforcing bars be provided in the footings. A minimum clearance of 3 inches should be maintained between steel reinforcement and the bottom or sides of the footing. In order for us to offer an opinion as to whether the footings are founded on soils of sufficient load bearing capacity, it is essential that our representative inspect the footing excavations prior to the placement of reinforcing steel or concrete. NOTE: The project Civil/Structural Engineer should review all reinforcing schedules. The reinforcing minimums recommended herein are not to be construed as structural designs, but merely as minimum reinforcement to reduce the potential for cracking and separations. 12. Seismic Design Criteria: Site-specific seismic design criteria to calculate the base shear needed for the design of the proposed structures are presented in the following table. The design criteria was obtained from the California Building Code (2001 edition) and is based on the distance to the closest '1_1 ~--., LJ L_f i __ J ,_j l..l l.! l_) \' \__I I--~ I ___ , Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 16 active fault and soil profile classification. The nearest active fault zone is mapped approximately 4 miles to the southwest of the project site. Parameter Value Reference Seismic Zone Factor, Z 0.40 Table 16-I Soil Profile Type Sc Table 16-J Seismic Coefficient, Ca 0.40Na Table 16-Q Seismic Coefficient, Cv 0.56Nv Table 16-R Near-Source Factor, Na 1.0 Table 16-S Near-Source Factor, Nv 1.2 Table 16-T Seismic Source Type B Table 16-U 13. Lateral Loads: Lateral load resistance for the structures supported on footing foundations may be developed in friction between the foundation bottoms and the supporting subgrade. An allowable friction coefficient of 0.30 is considered applicable. An additional allowable passive resistance equal to an equivalent fluid weight of 250 pounds per cubic foot (pcf) acting against the foundations may be used in design provided the footings are poured neat against the adjacent undisturbed formational materials or compacted fill soils. These lateral resistance values assume a level surface in front of the footing for a minimum distance of three times the embedment depth of the footing and any shear keys. For ground surfaces sloping down from footings at an inclination of 2 horizontal to 1 vertical, the allowable passive resistance should be reduced to 60 pcf. For variations between a level surface and 2 to 1 slopes in front of footings1 passive resistance values may be interpolated. 14. Settlement: Settlements under building loads are expected to be within tolerable limits for the proposed structures. For footings designed. in accordance with the recommendations presented in the preceding paragraphs, we anticipate that total settlements should not exceed 1 inch Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 17 and that post-construction differential settlements should be less than V2-inch in 25 feet. 15. Retaining Walls: Retaining walls must be designed to resist lateral earth pressures and any additional lateral pressures caused by surcharge loads on the adjoining retained surface. We recommend that unrestrained (cantilever) walls with level backfill be designed for an equivalent fluid pressure of 40 pounds per cubic foot (pcf). Unrestrained walls with 2 to 1 sloping backfill should be designed for a fluid pressure of 52 pcf. We recommend that restrained walls (i.e., the proposed walls supporting buildings or any walls with angle points that restrain them from rotation) with level backfill be designed for an equivalent fluid pressure of 40 pcf plus an additional uniform lateral pressure of 10H pounds per square foot where H is equal to the height of backfill above the top of the wall footing in feet. Restrained walls with 2 to 1 sloping backfill should be designed for an equivalent fluid pressure of 52 pcf plus an additional uniform lateral pressure of 13H pounds per square foot. Wherever walls 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 the case of unrestrained walls and one-half the anticipated surcharge pressure in the case of restrained walls. The preceding design pressures assume that the walls are backfilled with the clayey on-site soils and that there is sufficient drainage behind the walls to prevent the build-up of hydrostatic pressures from surface water infiltration. We recommend that drainage be provided by a composite drainage material such as Miradrain 6000/6200 and QuickDrain or equivalent. No gravel or perforated pipe is used with the Miradrain/QuickDrain system. The drainage material should terminate 12 inches below the finish surface where the surface is covered by slabs or 18 inches below the finish surface in landscape ,--, I_, I~ i_ ;, ~~-, r-', ~l ·~ J ' -' Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 18 areas. If the walls are backfilled with low expansion potential imported materials (Expansion Index less than 40) within a 1 to 1 zone behind the walls, the preceding values may be reduced to 35 pcf and 35 pcf plus 8H uniform for level backfills, and 45 pcf and 45 pcf plus 10H uniform for 2 to 1 sloping backfills. Backfill placed behind the walls should be compacted to a minimum degree of compaction of 90 percent using light compaction equipment. If heavy equipment is used, the walls should be appropriately temporarily braced. Retaining walls should be supported on footing foundations designed in accordance with the recommendations presented previously under Recommendation No. 11, "Footings". Lateral load resistance for the walls can be developed in accordance with the recommendations presented under Recommendation No. 13 "Lateral Loads" C. Concrete Slab-on-grade Criteria 16. Minimum Floor Slab Thickness and Reinforcement: Based on our experience, we have found that, for various reasons, floor slabs occasionally crack, causing brittle surfaces such as ceramic tiles to become damaged. Therefore, we recommend that all slabs-on-grade contain at least a minimum amount of reinforcing steel to reduce the separation of cracks, should they occur. Interior floor slabs should be a minimum of 5 inches actual thickness and be reinforced with No. 4 bars on 18-inch centers, both ways, placed at midheight in the slab. 17. Concrete Isolation Joints: We recommend the project Civil/Structural Engineer incorporate isolation joints and sawcuts to at least one-fourth the Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 19 thickness of the slab in any floor designs. The joints and cuts, if properly placed, should reduce the potential for and help control floor slab cracking. We recommend that concrete shrinkage joints be spaced no farther than approximately 20 feet apart, and also at re-entrant corners. However, due to a number of reasons (such as base preparation, construction techniques, curing procedures, and normal shrinkage of concrete), some cracking of slabs can be expected. 18. Slab Moisture Emission: Soil moisture vapor can result in damage to moisture-sensitive floors, some floor sealers, or sensitive equipment in direct contact with the floor, in addition to mold and staining on slabs, walls and carpets. The common practice in Southern California is to place vapor retarders made of PVC, or of polyethylene. PVC retarders are made in thickness ranging from 10-to 60-mil. Polyethylene retarders, called visqueen, range from 5-to 10-mil in thickness. The thicker the plastic, the stronger the resistance will be against puncturing. Although polyethylene (visqueen) products are commonly used, products designed specifically as vapor retarders possess higher tensile strength and are more specifically designed for and intended to retard moisture transmission into concrete slabs. The use of such products is highly recommended. 18.1 Vapor retarder joints must be lapped and sealed with mastic or. the manufacturer's recommended tape. To provide protection of the moisture retarder1 a layer of at least 2 inches of clean sand (minimum Sand Equivalent value of 50) on top and 2 inches at the bottom should l_] ' L ... J l __ j L .i L' I L~ L_l l __ j , _ _j •: _ _'; ~-I \_ __ j Carlsbad Airport Center Carlsbadr California also be provided. Job No. 05-9085 Page 20 The bottom clean sand layer may be omitted provided the low expansion capping material is free of any gravel which could damage the membrane. The clean sand layer(s) may be counted as part of the recommended low-expansion potential layer (see Recommendation No. 4). No heavy equipment, stakes or other puncturing instruments should be used on top of the liner before or during concrete placement. In actual practicer stakes are often driven through the retarder material, equipment is dragged or rolled across the retarder! overlapping or jointing is not properly implemented1 etc. All these construction deficiencies reduce the retarder's effectiveness. 18.2 The vapor retarders are not waterproof. They are intended to help prevent or reduce vapor transmission and capillary migration through the soil into the pores of concrete slabs. Waterproofing systems must supplement vapor retarders if full waterproofing is desired. The owner should be consulted to determine the specific level of protection required. 19. Exterior Slab Reinforcement: As a minimum for protection of on-site improvements, we recommend that all exterior pedestrian concrete slabs be founded on properly compacted, low-expansion potential fill soils as stated previously in Recommendation No. 4. The slabs should be 4 inches thick and reinforced with No. 4 bars at 24-inch centers, both waysr at the center of the slab, and contain adequate isolation and control joints. The performance of on-site improvements can be greatly affected by soil base preparation and the quality of construction. It is therefore important that all improvements are properly designed and constructed for the existing soil conditions. The improvements should not be built on loose soils or fills placed without our observation and testing. Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 21 For exterior slabs with the minimum shrinkage reinforcement, control joints should be placed at spaces no farther than 15 feet apart or the width of the slab, whichever is less, and also at re-entrant corners. Control joints in exterior slabs should be sealed with elastomeric joint sealant. The sealant should be inspected every 6 months and be properly maintained. D. Slope Performance 20. Slope Top/Face Performance: The soils that occur in close proximity to the top or face of even properly compacted fill or dense natural ground cut slopes often possess poor lateral stability. The degree of lateral and vertical deformation depends on the inherent expansion and strength characteristics of the soil types comprising the slope, slope steepness and height, loosening of slope face soils by burrowing rodents, and irrigation and vegetation maintenance practices, as well as the quality of compaction of fill soils. Structures and other improvements could suffer damage due to these soil movement factors if not properly designed to accommodate or withstand such movement. 21. Slope Top Structure Performance: Rigid improvements such as top-of-slope walls (with the exception of the planned restrained building walls), columns, decorative planters, concrete flatwork, and other similar types of improvements can be expected to display varying degrees of separation typical of improvements constructed at the top of a slope. The separations result primarily from slope top lateral and vertical soil deformation processes. These separations often occur regardless of being underlain by cut or fill slope material. Proximity to a slope top is often the primary factor affecting the degree of separations occurring. u ,, \_,_ __ _] LJ I L __ J ' ' L_-' ,---1 '___ -~ j Ca'rlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 22 Typical and to-be-expected separations can range from minimal to up to 1 inch or greater in width. In order to minimize the effect of slope-top lateral soil deformation, we recommend that the top-of-slope improvements be designed with flexible connections and joints in rigid structures so that the separations do not result in visually apparent cracking damage and/or can be cosmetically dressed as part of the ongoing property maintenance. These flexible connections may include "slip joints" in wrought iron fencing, evenly spaced vertical joints in block walls or fences, control joints with flexible caulking in exterior flatwork improvements, etc. E. Pavements 22. Concrete Pavement: We recommend that concrete pavements subject only to automobile and light truck traffic be 6 inches thick and be supported directly on properly prepared on-site subgrade soils. Concrete pavement for areas subject to occasional heavy truck traffic1 such as trash trucks, should have a minimum thickness of 8 inches. The upper 8 inches of the subgrade below the slab should be compacted to a minimum degree of compaction of 95 percent just prior to paving. The concrete should conform to Section 201 of The Standard Specifications for Public Works Construction, 1994 Edition, for Class 560-C-3250. In order to control shrinkage cracking1 we recommend that saw-cut1 weakened-plane joints be provided at about 15-foot centers both ways. The pavement slabs should be saw-cut no more than 24 hours after the placement of the concrete. The depth of the joint should be one-quarter of the slab thickness and its width should not exceed 0.02-feet. Reinforcing steel is not necessary unless it is desired to increase the joint spacing recommended above. Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 23 23. Asphalt Concrete Pavements: It is our understanding that the City's Standards require a minimum Traffic Index of 4.5 for the design of the structural section for parking lots and automobile driveways with a minimum of 3 inches of asphalt concrete. For truck routes subject to occasional heavy trucks (such as trash, fire, and delivery trucks) with a Traffic Index of 5Y2 , the minimum section required by the City is 4 inches of asphalt concrete on 6 inches of aggregate base. Based on our experience with materials similar to those on site, and the City of Carlsbad minimum traffic index of 4.5 for automobile drives and parking stalls and 5.5 for truck drives, we anticipate that pavement sections for the development should consist of 3 inches of asphalt concrete on ?Y2 inches of aggregate base for parking stalls and automobile traffic channels and 4 inches on 9 inches for pavements subject to up to 8 heavy trucks per week. Final pavement section recommendations should be based on R-value (Resistance) tests performed on bulk samples of the soils that are exposed at the finished subgrade elevations across the site at the completion of the mass grading operations. Asphalt concrete should consist of Type III-C2-AR-4000 conforming to the Standard Specifications for Public Works Construction, 2000 Edition (Standard Specifications), Section 400-4 and be placed in accordance with Section 302-5. Aggregate base should conform to the requirements for Crushed Aggregate Base or Crushed Miscellaneous Base in Section 200-2 of the Standard Specifications. The upper 6 inches of the pavement subgrade soil as well as the aggregate base layer should be compacted to a minimum degree of compaction of 95 percent. Preparation of the subgrade and placement of the asphalt concrete and base materials should be performed under the observation of our representative. ' ' L__, r' L] '· -~j ~ _j Carlsbad Airport Center Carlsbad, California F. General Recommendations Job No. 05-9085 Page 24 24. Project Start Up Notification: In order to minimize any work delays during site development, this firm should be contacted 24 hours prior to any need for observation of footing excavations or field density testing of compacted fill soils. If possible, placement of formwork and steel reinforcement in footing excavations should not occur prior to observing the excavations; in the event that our observations reveal the need for deepening or redesigning foundation structures at any locations, any formwork or steel reinforcement in the affected footing excavation areas would have to be removed prior to correction of the observed problem (i.e.1 deepening the footing excavation, recompacting soil in the bottom of the excavation, etc.) IX. GRADING NOTES Geotechnical Exploration, Inc. recommends that we be retained to verify the actual soil conditions revealed during site grading work and footing excavation to be as anticipated in this "Report of Preliminary Geotechnical Investigation" for the project. In addition, the compaction of any fill soils placed during site grading work must be observed and tested by the soil engineer. It is the responsibility of the grading contractor to comply with the requirements on the grading plans and the local grading ordinance. All retaining wall and trench backfill should be properly compacted. Geotechnical Exploration, Inc. will assume no liability for damage occurring due to improperly or uncompacted backfill placed without our observations and testing. Cadsbad Airport Center Carlsbad, California X. LIMITATIONS Job No. 05-9085 Page 25 Our conclusions and recommendations have been based on available data obtained from our field investigation and laboratory analysis, as well as our experience with similar soils and formational materials located in this area of Carlsbad. Of necessity/ we must assume a certain degree of continuity between exploratory excavations. It is, therefore, necessary that all observations, conclusions, and recommendations be verified at the time grading operations begin or when footing excavations are placed. In the event discrepancies are noted1 additional recommendations may be issued/ if required. The work performed and recommendations presented herein are the result of an investigation and analysis that meet the contemporary standard of care in our profession within the City of San Diego. No warranty is provided. This report should be considered valid for a period of two (2) years, and is subject to review by our firm following that time. If significant modifications are made to the building plans, especially with respect to the height and location of any proposed structures1 this report must be presented to us for immediate review and possible revision. It is the responsibility of the owner and/or developer to ensure that the recommendations summarized in this report are carried out in the field operations and that our recommendations for design of this project are incorporated in the structural plans. We should be retained to review the project plans once they are available1 to see that our recommendations are adequately incorporated in, the plans. I ~ , L,_, t__j \ ___ j \___) \ __ j L~ \_ 1 l j \_ __ _/ ,, L_,_! Carlsbad Airport Center Carlsbad, California Job No. 05-9085 Page 26 This firm does not practice or consult in the field of safety engineering. We do not direct the contractor's operations, and we cannot be responsible for the safety of personnel other than· our own on the site; the safety of others is the responsibility of the contractor. The contractor should notify the owner if any of the recommended actions presented herein are considered to be unsafe. The firm of Geotechnical Exploration, Inc. shall not be held responsible for changes to the physical condition of the property, such as addition of fill soils or changing drainage patterns, which occur subsequent to issuance of this report and the changes are made without our observations, testing, and approval. Once again, should any questions arise concerning this report, please feel free to contact the undersigned. Reference to our Job No. 05-9085 will expedite a reply to your inquiries. Respectfully submitted, GEOTECHNICAL EXPLORATION, INC. VICINITY MAP Thomas Bros. Guide San Diego County pg. 1127 Carlsbad Airport Center Wright Place and Palomar Oaks Way Carlsbad, CA. Figure No.I Job No. 05-9085 I I . REFERENCE: This Plot Pion was prepared from on existing electronically tran sferred CAD file provided by the client I and from on-site field reconnaissance perform ed by GEl. .l NOTE: This Plot Plan is not to be used for legal purposes. Locations and dimensions ore approxi- mate. Actual property dimensions and locations of utilities may be obtained from the Approved Building Pions or the "As-Built" Grading Plans. ~' ,, '\, 05-9085-pl ,, '\, '\ \, -......... -............ ......... ('J ~-......... .... ~ -}-..?:: OQ, -J"< ~ " -......... _ .' Legend / ,./ t 2 Cut-RII contact from Sheet 5 of As-Built grading plan for "C.T. 81-46 Unit N0.1. Airport Business Center-Carlsbad'' by Rick Engineering Company, dated 1/22/90 INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING I I I I I I I I I I I I I I I I I I &i I I I I ~t I ' ' I I I I I I i i i i I I I I I I I I I I ' I I I I ' I , I I I I I I I I I I I I ~ <.'J!8'&.!"'""!5a {I) SCALE: 111 = 60' (approximate) ' I I i ' I I I I I I I I I I i i I I i i I I I I I I I I I I I I I I I I I I I I I I I I I I I I SITE PLAN Carlsbad Airport Center Wright Place and Palomar Osks Way Carlsbad, CA. Figure No. II Job No. 05-9085 Geotechnical Exploration, Inc. Apri/2006 I Carlsbad Airport Center Wright Place and Palomar Oaks Way Carlsbad, CA. Excerpt from As-Built Grading Plan by Rick Engineering Company titled "Grading Plans for C.T. 81-46 Unit No. l , Carlsbad, California, Sheet 5 of l l " dated Jan 22, 1990. Figure No. Ill Job No. 05-9085 EQUIPY:NT DIMENSION & TYPE OF EXCAVATION DATE LOGGED Truck-mounted Auger Drill Rig 8-lnch diameter boring 11-22-05 SURFACE ELEVATION GROUNDWATER/ SEEPAGE DEPTH LOGGED BY :t 161' Mean Sea Level Not Encountered WOH FIELD DESCRIPTION ~ AND t:. ii:'U ~ ~'6" t: CLASS! FICA TION w oa ::i~ :i.e wo: ~~ ~ (.)i= ~i= j~ ::5~ :5w ii:!!l -(/) ~0 ~if) x:z w 0~ ~l!:l 0 -~ -0 -49% passing #200 sieve. 7.0 12.5 120.0 2 : -material appears dry and chunky in drive sample. 11.9 103.2 86 41 3" 13.1 99.9 83 4 I -38% passing #200 sieve. 11.7 91.7 76 41 3" 6 I -material appears dry and chunky in drive 12.4 101.0 84 sample. 8 I FILL (Qaf) 10 I 15.9 103.6 86 32 3" 16.4 103.0 86 12 I 14 101.4 85 41 3" 16 98.2 82 107.8 18 JOB NAME I .Y WATER TABLE Carlsbad Center cgJ LOOSE BAG SAMPLE SITE LOCATION [II IN-PLACE SAMPLE Carlsbad, CA • MODIFIED CALIFORNIA SAMPLE JOB NUMBER REVIEWED BY LDRIWDH lOG No . ~ FIELD DENSITY TEST 06-9086 B-1 FIGURE NUM3ER ~ STANDARD PENETRATION TEST IVa I I I I I ! ; ~ ~I ~ "' a! tS ~ :$ (!) g z 0 I= ~ 0 -' 0.. ~ EQUIPMENT DIMENSION & TYPE OF EXCAVATION DATE LOGGED Truck-mounted Auger Drill Rig 8-inch diameter boring 11-22-05 SURFACE ELEVATION GROUI'lJWATERI SEEPAGE DEPn-t LOGGED BY :t 162' Mean Sea Level Not Encountered WDH FIELD DESCRIPTION ~ ~ AND ~ ~:a 0 ~:a ~ ~ CLASSIFICATION ci z t: II[ t: w ::d~ + 0 0 _J li wcr: w~ ::::;;>->-0 _j <n Cil I 0 DESCRIPTION At-Ll REMARKS uj 0::> ~<n ::>::> ::>f-!:::::;; z.g f-:'5~ ::::;;f-::::!E-z f-m u -en -en ~'15 <z ~ ~z Eb ::::;; (Grain size, Density, Moisture, Color) uj a.o a. as f--~as o=> >-&~ w* c.. 0 ~ _.o Cl en ::i ~::::;; ~Cl :::<:CJ Cl-~(.) <DO ~~ -SANDY CLAY Stiff. Moist. Light brown. ICL -8 B FILL (Qat) 2 -~~ i.X -56% passing #200 sieve. 16.3 96.2 80 32 3" --55% passing #200 sieve. 17.9 97.5 81 4 -~ -I SILTY -SAND, fine-=9raTntid-:--M-edium----rsr~f dense. Moist. Light brown. 6-~ -34% passing #200 sieve. 16.5 102.8 86 30 3" ~ -~ FILL (Qat) ~ 8-~ ~ -~ 10-"CIAYEYSANQ-filie:Qriililed.-MedlUin---rsc -dense. Moist. Light brown. 17.9 103.5 86 26 3" 12-FILL (Qat) ~ -§ 14 IV 11.0 122.0 97 s -~-43% passing #200 sieve. 16-21 .1 88.2 73 27 3" -~ 18 -g -~ m~ 20 ~ 16 2" -Bottom@ 20' 22- y JOB NAME WATER TABLE Carlsbad Airport Center ~ LOOSE BAG SAMPLE SITE LOCATION [I] IN-PLACE SAMPLE Carlsbad, CA • JOB NUMBER REVIEWED BY LOG No . MODIFIED CALIFORNIA SAMPLE LDRJWDH II] 05-9085 a&--B-2 FIELD DENSITY TEST FIGURE NUMBER FJ!ploratlon, me. ~ STANDARD PENETRATION TEST IVb ~ iii ii. C! /EQUIPMENT DIMENSION & TYPE OF EXCAVATION Truck-mounted Auger Drill Rig 8-inch diameter boring SURFACE ELEVATION GROUNDWATER/ SEEPAGE DEPTH :!: 162' Mean Sea level Not Encountered FIELD DESCRIPTION AND ti CLASSIFICATION I DESCRIPTION At-1> REw.RKS ..... fu 0 2 FILL (Qaf) 4 6 8 10 12 DEL MAR FORMATION (Td) 14 16 Bottom@ 16' ~ ~'a UJ UJO:: UJ>-~~ ~~ a.. en a..z ,(5 0 UJ ~::::E ~0 17.8 106.9 17.3 100.9 15.9 110.0 DATE LOGGED 11-22.05 LOGGED BY WDH ~ 1E ~~ UJ c::i + ' ~ ::EO:: ?5r: r:q :::>:::> __J :z'~ ..... ~ti) ~(I) u;::::E s:z h:o ~ru ru't5 it.z o=> i'ti8 ..JO O::::E ::::EO 0~ <DO 88 36 3" 84 35 3" 45 3" 67 2" lr ~L---~--~~------------------------------------~~--~----~--~--~~~----~--~~ <( 0 i ~ ~ g z i ~ .Y ~ [II • ~ ~ WATER TABLE LOOSE BAG SAMPLE IN-PLACE SAMPLE MODIFIED CALIFORNIA SAMPLE FIElD DENSITY TEST STANDARD PENETRATION TEST JOB NAME Carlsbad Airport Center SITE LOCATION Carlsbad, CA JOB NUMBER REVIEWED BY LDR/WDH LOG No. 05-9085 :;&= ... B-3 AGURE NUMBER IVc ~ I I I I I ------------- EQUIF't.£NT DIMENSION & TYPE OF EXCAVATION Truck-mounted Auger Drill Rig 8-lnch diameter boring SURFACE 8.£VATION GROUNrM'ATER/ SEEPAGE DEPTH :t 164' Mean Sea Level Not Encountered ~ ~ [!] FIELD DESCRIPTION AND CLASSIFICA TlON some of gray-brown claystone. Medium dense. Moist. Light brown. ALL(Qaf) -39% passing #200 sieve. -black soil in sampler tip. -rultings from 11' to 14' were black with organics; very strong organic odor. -some gray clay (CH) chunks in sample. Bottom@ 20' JOB NAME WATER TABLE Carlsbad LOOSE BAG SAMPLE SITE LOCATION IN-PLACE SAMPLE Cartsbad,CA ~ ~:i w w~ ~~ ui= :5!!2 ~CI) t~ :Zifi -0 20.7 103.2 20.2 99.4 18.5 107.7 20.6 103.5 Center !MTELOGGED 11·22..05 LOGGED BY WDH ~ ~'[ :;~ :;- =>i= 3~ ;;!a xrn ~~ ~~ • MODIFIED CALIFORNIA SAMPLE JOB NUMBER REVIEWED BY LDRIWDH 0 FIELD DENSITY TEST 05-9085 FIGURE NUMBER ~ STANDARD PENETRATION TEST IVd ~ 85 31 3" 83 26 3" 90 35 3" 86 39 3" 21 2" LOG No . B-4 EQUifVENT Dlt.ENSION & TYPE OF EXCAVATION DATE LOGGED Truck-mounted Auger Drtll Rig 8-lnch diameter bortng 11-22-05 SURFACE ELEVATION GROUNDWATER/ SEEPAGE DEPTH LOGGED BY ::t 165' Mean Sea Level Not Encountered WDH FIELD DESCRIPTION ~ AND ~ ~E ~ ~E t: CLASSIFICATION w ;:,:~ ci + . ~i wa: ~~ ~~ ~c:! ....i ~ oi= ~~ ~-~~ ~!!2 ~en ~!!2 -~ -(I) ~'!5 zffi ~!I x:z: ~8 0~ ~i ~~ w~ _.o c -C o-mo FILL (Qaf) 1 I 2 -30% passing #200 sieve. 9.5 100.1 83 40 3R I 3 4 I 5 I 49 3" I 6 7 Bottom @ 6.5' 8 y WATER TABLE JOBNAA£ carts bad Center [81 LOOSE BAG SAMPLE SITE LOCATION I [I] IN-PLACE SAMPLE Carlsbad, CA • MODIFIED CALIFORNIA SAMPLE JOBNUt.eER REVIEWED BY LDRIWDH LOG No. [!] FIELD DENSITY TEST 05-9086 B-5 I FIGURE NUt.IIER ~ STANDARD PENETRATION TEST IVe EQUI~NT DIMENSION & TYPE OF EXCAVATION Truck-mounted Auger Drill Rig 8-inch diameter boring SURFACE ELEVATION GROUNDWATER/ SEEPAGE DEPTli :t 165' Mean Sea Level Not Encountered t: :X: ~ FIELD DESCRIPTION AND CLASSIFICATION ----~~~jg~~--------CLAY. .:>un. VVet. Ught brown. ~ i'i:'D w o.e, wa: ~~ :s~ ~(I) ~0 q.:z zw -:::IE _c 23.4 96.6 Y. ~ [I) FILL (Qaf) -becomes very stiff. gray Dense. Very moist Ught brown. DEL MAR FORMA TlON (Td) Bottom 20' WATER TABLE JOB NAME Carlsbad LOOSE BAG SAMPLE SITE LOCATION IN-PLACE SAMPLE Carlsbad,CA Center DATE LOGGED 11-22-05 LOGGED BY WDH ~ i'i:'D ::d~ Oc.. ::::;:~ ~~ ::l~ ::Ern 1=-~~ a..O o::::E • MODIFIED CALIFORNIA SAMPLE JOB NUMBER REVIEWED BY LDRIWDH m FIELD DENSITY TEST 05-9085 FIGURENU~R ~ STANDARD PENETRATION TEST IVf ~ 29 3" 24 3" 21 2" 23 2" 81 2" LOG No . B-6 EQUIPJ.£NT DIMENSION & TYPE OF EXCAVATION Truck-mounted Auger Drill Rig 8-lnch diameter boring SURFACE ELEVATION GROUNCM'ATER/ SEEPAGE DEPTH :t 164' Mean Sea Level Not Encountered FIELD DESCRIPTION AND l ~'D t: CLASSIFICATION ~~ o,a. i ~i; _, ~ E 0 DESCRIPTION N¥J REMARKS :5~ ! :5cn (Grail size, Densly, Molstl.n, Cdor) q.-~ifi ~~ 0 -0 ~}~ SILTY CLAY. y~ stiff. MOiSt Ught brown and CH -gray, interbedded. -t~~ DEL MAR FORMATION (Td) ~ - 1- -~ ~ -~~ - 2-~1~ -~~ -~ -~~i' -84% passing #200 sieve. 24.9 3-~ - - 4- -Bottom @ 3.5' - - 5 - - I - - 6- ~ - ! - ~ - ~ q Y. WATER TABLE JOB NAME ~ Carlsbad Ali t"'•1 Center ~ LOOSE BAG SAMPLE SITE LOCATION i [!] IN-PLACE SAMPLE Cartsbad, CA ~ • MODIFIED CALIFORNIA SAMPLE JOB NUt.I!ER REVIEWED BY I ~ FIELD DENSITY TEST 05-9085 ·~~ FIGURE NUMBER , ........ ~ STANDARD PENETRATION TEST IVg ~ DATE LOGGED 11-22-05 LOGGED BY WDH ~ ~'D ::i~ Ca. ::IE~ ~i; ~~ ~-;~ ~~ LDRIWDH -,nc. ~ a-+ ' ~ i;o __j ·o ffi~ zw ~z ~~ o=> 0~ _,o wo CDO 28 LOG No . B-7 III 2" I I I I I EQUimENT DIMENSION & TYPE OF EXCAVATION DATE LOGGED Truck-mounted Auger Drill Rig 8-inch diameter boring 11-22-05 SURFACE ELEVATION GROUNJ:MIATERI SEEPAGE DEPTH LOGGED BY ± 167' Mean Sea Level Not Encountered WDH FIELD DESCRIPTION ~ AND ~ ir'ff ~ ~'[ CLASS I FICA liON .....,. It c:i t: ~~ o,e ::::.;:;~ 0 + • 0~ ~~ ::::.;:;~ ~q _. ~ u) ::lj:! ;:)~ .J ==~ ~f3 t 0 DESCRIPTION AND REMARKS ~~ z~ ~ ~ ~ ~~ ::::EU) ;!ffi U)::::E !!5 (Grain size, Dendy, Moisllle, Color) ~0 ~-zl; <z o=> w U) ~w 0~ io W;a~! ~8 ~8 ~~ 0 =:; _;:E -0 o~ ~ SILTY CLAY. Hard. Dry to moist Ught brown ICH -with yellow-brown seams/fractures. -~ DEL MAR FORMATION (Td) -~ 1- -~ - - 2-~~ I 53 2" - -I -I 3 -~~ -~~:· - 4- -Bottom@ 3.5' - - 5 - - - - 6- - - - .Y. WATER TABLE JOB NAME Cartsbad Airport Center ~ LOOSE BAG SAMPLE SITE LOCATION m IN-PLACE SAMPLE Cartsbad, CA • MODIFIED CALIFORNIA SAMPLE JOB NUMBER REVIEWED BY LDRIWDH lOG No. ~ FIELD DENSITY TEST 05-9085 ~-B-8 FIGURE NUMBER Ellploratton. w. ~ STANDARD PENETRATION TEST IVh EQUIPMENT DIMENSION & TYPE OF EXCAVATION DATE LOGGED Truck-mounted Auger Drill Rig 8-lnch diameter boring 11-22-05 SURFACE ELEVATION GROUNDWATER/ SEEPAGE DEPTH LOGGED BY :1: 169' Mean Sea level Not Encountered WDH FIELD DESCRIPTION AND ~ ~~ ~ ~'D CLASSIFICATION li w ~~ C,s, .... wa:: ~~ ~~ § 0 ~ DESCRIPllON AND REMARKS uj (.)~ ~(I) ! !I ti :5cn :5cn -!!l (Grain size, Densly, Moistln, Color) u:! ~-a..:z ~~ x:z Ei; (":j ~~ t~ ~~ :::::0 I SILTY CLAY. Very stiff. Moist. Ught brown and ICH -gray. -~: DEL MAR FORMATION (Td) -~~ 1-~ -I -I - 2- - -~I I -~ffi 3-~ -~ - 4 - -Bottom @ 3.5' - - 5- - ~ - - b 6-(!) ..J ~ - 0 w (!) - 2 ~ ti: 0 ... - .Y WATER TABLE JOB NAME Carlsbad Airport Center [81 LOOSE BAG SAMPLE SITE LOCATION m IN-PLACE SAMPLE Carlsbad, CA • MODIFIED CALIFORNIA SAMPLE JOBNU~ER REVIEWED BY LDRIWDH 0 FIELD DENSITY TEST 06-9085 aa-FIGURE NUMBER lbploratlon, Inc. ~ STANDARD PENETRATION TEST lVI ~ ci ~i + . ~ci _j :Z~ ffi~ §8 o :::::o c~ .... o CD (.) 27 LOG No . B-9 ~ ci 0~ ~ffi !In (":j~ 2" I I I I I I I I ~ ~ ~ § ~ li t i ~ § I / EQUIPt.ENT DIMENSION & TYPE OF EXCAVATION Truck-mounted Auger Drill Rig 8-lnch diameter boring SURFACE aEVATlON GROUNDWATER/ SEEPAGE DEPTH :t 171' Mean Sea Level Not Encountered FIELD DESCRIPTION AND CLASSIFICATION ~ Iii! DESCRIPTlON AND REMARKS ~ 1 ~ (Grain size, Oensly, Molsl1.re, Color) _ J~~ SILTY CLAY. Very Sfiff. Moist Gray. -J~~ DEL MAR FORMA110N (Td) -~~~~ 1-:'ir- -IX =~~~ 2=~~:1 -~} 3 -1: ~ Si[fi-s"A"NQfine:QraTneciveiYder.se-:---lsM -i:l: ~ Moist. Gray. \ DEL MAR FORMATION (Td) /'r- - 4 - -Bottom @ 3.5' - - 5 - - - - 6 - - - - JOB NAME ~ w~ Oj: ~"' ~-ad~ ~'ff ~ o.e, ::::!:~ ~~ =>j: :50 ::::!:U) ~z t=-zw ~0 -0 0::::!: .Y WATER TABLE Carlsbad ;.:, t'V' ~ Center ~ LOOSE BAG SAMPLE SITE LOCATION IIl IN-PLACE SAMPLE Carlsbad, CA • MODIFIED CALIFORNIA SAMPLE JOB NUMBER REVIEWED BY 0 FIELD DENSITY TEST 05.S086 .41P'".41~. FIGURE NUMBER ~ ... ~ ..... ~ STANDARD PENETRATION TEST IV) -~ DATE LOGGED 11-22-05 LOGGED BY WDH .-. ~ ~'ff ~ ~ Ill CD. ci z ~ ::::e-~q + • 0 :::>~ -~ Ci5 :!liffi ffi~ Zen z ;::!z ~z § o::::::> ic ~8 _,o 0~ mo 101 67 2" LDRIWDH LOG No . .-Inc. B-10 EQUJPP.£NT Dlt.eiSION & TYPE OF EXCAVATION Truck-mounted Auger Drtll Rig 8-inch diameter boring SURFACE ELEVATION GROUNDWATER/ SEEPAGE DEPllf :t 189' Mean Sea Level Not Encountered FIELD DESCRIPTION AND ~ ~'ts t.: CLASSIFICATION w oa i i wa: ~?= ~ 0::> :I: DESCRIPTION AND REMARKS li: ~t; ~U) (Gialn size, Densly, Molst\Je, Colo~ 'T-Q.ifi w ~~ to 0 t SILTY SANQTne:.grained. Very dense. Dry. SM -Light brown. -DEL MAR FORMATION (Td) - 1- - - - 2- - - - 3- - - 4- -Bottom @ 3.5' - - 5- - ~ - - ~ 6- - I - - i: ~ .Y WATER TABLE JOB NAME ~ Carlsbad A1rpon Center ~ LOOSE BAG SAMPLE SITE LOCATION i IT] IN-PLACE SAMPLE Carlsbad, CA § • MODIFIED CALIFORNIA SAMPLE JOBNJMBER REVIEWED BY ! 0 FIELD DENSITY TEST 05-9085 ......... FIGURE NUWER .. ~,., ... ~ STANDARD PENElRATION TEST IVk ~ DATE LOGGED 11-22-05 LOGGED BY WDH ~ ~'ts ::d~ Ca. :::!:- ~i=! =>?= :!:en -en ~~ li:o 0~ LDRIWDH Inc. ~ i! + '. ~ ...J :Z 0 ~!Z §§ o=> ...JO CDU 84 lOG No . B-11 """ li 2" I I I I I EQUIPMENT DI~SJON & TYPE OF EXCAVATION DA.TE LOGGED Truck-mounted Auger DrUI Rig 8-lnch diameter boring 11-22-05 SURFACE B.EVATJON GROUNDWATER/ SEEPAGE DEPTH LOGGED BY :t 168' Mean Sea Level Not Encountered WDH FIELD DESCRIPTION ~ AND ~ i!i:'g: ~ ~'R CLASSIFICATION ..,. ~ q t: ~~ c~ ::l<~ ::l<~ c + ' 0~ _, ~ uj ~~ ~i2 :::::>~ ~q J ~ffi ~ 0 DESCRIPTION AKl REMARKS :s~ zg 3:!z !i ~ 0 ~ffi ::l<(f) ~~ "'::E a..:z: (Gnin size, Oensly, Moisttre, Cdo~ <4 ~-~-i~ z'D ~i:5 0~ ~~ ~ ~~ WOJ!! _,o c :::::> _!i to o~ w 0 alO ~){ SILTY CLAY. Stiff. Moist Brown. ICH - -~~ DEL MAR FORMATJON (Td) - 1-~ - -~ -['}{ 2 11 I --------------------------1-sl;,f SILTY SAND. fine-grained. Very dense. Moist. -Ught brown. -DEL MAR FORMATJON (Td) -75 2" 3- - - 4- -Bottom @ 3.5' - - 5- - - - ~ w 6- - - - .Y WATER TABLE JOB NAME Carlsbad Airport Center 181 LOOSE BAG SAMPLE SITE LOCA TJON [I] IN-PLACE SAMPLE Cartsbad, CA • MODIFIED CALIFORNIA SAMPLE JOB NUMBER REVIEWED BY LOG No. LDRIWDH [!] FIELD DENSITY TEST 05-SOBS :;;=---=-B-12 FIGURE NUMBER ~ STANDARD PENETRATION TEST M 0 c.. ~ u; z w 0 >-et: 0 CD Q 135 1\ \ \ \ \ \ ' 130 '\ ~ 1\ I\ \ \ 1\ \ \ 125 1\ \ \ \ Source of Material s-1@1.0· \ \ Light gray-brown CLAYEY \ \ Description of Material 120 \ SAND (SC} ~ ~ 1\ \ Test Method ASTM 01557 Method A "' \ \ ,. ~· [\ I '[\ \ 115 .. ~ ~ I ~ '"' ~ ~\ 1\ TEST RESULTS ' \~ \ ~ Maximum Dry Density 120.0 PCF 110 \ Optimum Water Content 12.5 o/o \ 1\ 1\ \ \ \ \ \ 1\ A TTERBERG LIMITS 105 \ \ ,----· \'f\ ~\ LL PL PI ---- \ ' 100 \ \. 1\ \ Curves of 100% Saturation '\ ' 1\ for Specific Gravity Equal to: -..;..: \. \ 2.80 95 I'\ ' \ i\. 2.70 1\ \. i\ ' 2.60 \ \ '\ 90 '\ ~ 1\ \ ' \. 1'-\ ~ 85 '\. ' 1\ ' \. ' \. ~ \. '\ 80 " 1"- ' 1\ 1\ 75 " 0 5 10 15 20 25 30 35 40 45 WATER CONTENT, % 4(;-4&-11 Geotechnical MOISTURE-DENSITY RELATIONSHIP Exploration, Inc. Figure Number: Va ..>. --"""= ~ Job Name: Carlsbad Airport Center ~:~~ ~ Site Location: Carlsbad, CA Job Number: 05-9085 I I I I I I I I I I I I 135 [\""'\ i\ \ 1\ i\ -, 130 1\ f\ \ \ \ 1\ ' \ 125 \ ~' Source of Material B-2@ 14.0' ~~ A~\ Description of Material light brown CLAYEY SAND 120 {SC} 'I 1\ \ Test Method ASTM 01557 Method A II 1\ l\ 1\ I ll 1\ 115 '-\ 1\ I' \ \ 1\ TEST RESULTS 1\' \ 1\ Maximum Dry Density 122.0 PCF 110 1\ ~ \ \ Optimum Water Content 11.0% 'ti \ c. 1\ ~ \ (/) 105 1\1\ A TTERBERG liMITS z w \ 0 & 1\ \ _!:!:_ PL PI 0 \ t\ ---- \ ' 100 \ [\ 1\ \ Curves of 100% Saturation [\' '\ 1\ for Specific Gravity Equal to: \ \ 1\. 2.80 95 1\' \ ~ 2.70 1\. l\. !'\ ' 2.60 l\. ' 90 \. 1\ 1\. ' f\ ""' 1\. i'\ "' \ I'\. ~ ~ 85 '\ 1\ '" " ..... 0 Cl 1\. \ -' D.. ' 1\ 1;'i I" ', __ j 0 w 80 1"'.. C!l ~ too.. i"\. n: Cl "\, ~ !'.... f'\. 0 =R= !'-. '\ D.. g; 1\. -.;;; 75 r" ; ___ ; 0 5 10 15 20 25 30 35 40 45 WATER CONTENT,% 41;4&11 Geotechnical MOISTURE-DENSITY RELATIONSHIP Exploration, Inc. Figure Number: Vb ~~~ Job Name: Carlsbad Airport Center ~ f/ Site Location: Carlsbad, CA Job Number: 05-9085 5,000 4,000 3,000 / '0 v c. :i" 1-/ (!) z w a:: 1-(/) a:: ~ <( w J: (/) 2,000 ~ / / 1,000 v L; 0 0 1,000 2,000 3,000 4,000 5,000 l_i "' NORMAL PRESSURE, psf ~ >::: "' >-0 :J 0.. ~ Specimen Identification Classification t. MC% c • @ • B-2@ 14.0' light brown CLAYEY SAND (SC) 897 25 (!) .., "-(!) r-', ,_: <!: 0 "-DC <{ a :i ".l <!: i5 "' "' 4Jr4eii Geotechnical DIRECT SHEAR TEST 0 "' <!: iii Figure Number: Vc ::t: Exploration, Inc. rn ~ ...3,. ....-=1~ Job Name: Carlsbad Airport Center :::%:~~ Site Location: Carlsbad, CA a ~ rn Job Number: 05-9085 =>