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HomeMy WebLinkAboutCT 01-13; LAGUNA POINT; REPORT OF GEOTECHNICAL INV LAGUNA POINT; 2001-12-17Geotechnics Incorporated 7 Principals: Anthony F. Belfast Michael P. Imbriglio W. Lee Vanderhurst REPORT OF GEOTECHNICAL INVESTIGATION LAGUNA POINT CONDOMINIUMS 539 LAGUNA DRIVE CARLSBAD, CALIFORNIA prepared for: Wave Crest Resorts II 829 Second Street, Suite A Encinitas, Califomia 92024 by GEOTECHNICS INCORPORATED ProjectNo. 0703-001-00 Document No. 1-1248 December 17,2001 9245 Activity Rd., Ste. 103 • San Diego, California 92126 Phone (858) 536-1000 • Fax (858) 536-8311 Geotechnics Incorporated December 17, 2001 Principals: Anthony F. Belfast Michael P. Imbriglio W. Lee Vanderhurst Wave Crest Resorts II 829 Second Street, Suite A Encinitas, Califomia, 92024 ProjectNo. 0703-001-00 Document No. 1-1248 Attention: Mr. Bill Canepa SUBJECT: REPORT OF GEOTECHNICAL INVESTIGATION Laguna Point Condominiums 539 Laguna Drive Carlsbad, California Dear Mr. Canepa: In accordance with your request, we have completed a geotechnical investigation for the proposed Laguna Point Condominium complex in Carlsbad, Califomia. This report presents the results of our investigation and provides recommendations regarding site preparation, earthwork constmction, and the geotechnical aspects of pavement and foundation design. Based on the results of our investigation, we consider that the proposed construction is feasible from a geotechnical standpoint. We appreciate this opportunity to provide professional services. If you have any questions or comments regarding this report or the services provided, please do not hesitate to contact us. Respectfully submitted, GEOTECHNICS INCORPORATED Anthony F. Belfast, P.E. Principal AFB/MA Distribution: (3) Addressee 9245 Activity Rd., Ste. 103 • San Diego, Califomia 92126 Phone (858) 536-1000 • Fax (858) 536-8311 REPORT OF GEOTECHNICAL INVESTIGATION LAGUNA POINT CONDOMINIUMS 539 LAGUNA DRIVE CARLSBAD, CALIFORNIA TABLE OF CONTENTS 1.0 INTRODUCTION 1 2.0 SCOPE OF SERVICES 1 3.0 SITE DESCRIPTION 2 4.0 PROPOSED CONSTRUCTION 2 5.0 GEOLOGY AND SUBSURFACE CONDITIONS 3 5.1 Santiago Formation 3 5.2 Bay Point Formation 3 5.3 Residual Soil 4 5.4 Fill 4 5.5 Groundwater 4 6.0 GEOLOGIC HAZARDS AND SEISMICITY 5 6.1 Seismicity 5 6.2 Ground Rupture 5 6.3 Liquefaction and Dynamic Settlement 6 6.4 Subsidence 6 6.5 Landslides and Lateral Spreads 6 6.6 Tsunamis, Seiches, Earthquake Induced Flooding 6 7.0 CONCLUSIONS 6 8.0 RECOMMENDATIONS 8 8.1 Plan Review 8 8.2 Grading and Excavation Observation 8 8.3 Earthwork 8 8.3.1 Site Preparation 9 8.3.2 Fill Compaction 10 8.3.3 Fill Materials 11 8.4 Temporary Excavations 11 8.5 Lateral Pressures on Shoring 12 8.6 Surface Drainage 12 8.7 Foundation Recommendations 13 8.7.1 Site Seismic Parameters 14 8.8 On-Grade Slabs 15 8.8.1 Moisture Protection for Interior Slabs 15 8.8.2 Exterior Slabs 16 Geotechnics Incorporated REPORT OF GEOTECHNICAL INVESTIGATION LAGUNA POINT CONDOMINIUMS 539 LAGUNA DRIVE CARLSBAD, CALIFORNIA TABLE OF CONTENTS (CONTINUED) 8.9 Earth Retaining Structures 16 8.10 Pavement 17 8.10.1 Asphalt Concrete 17 8.10.2 Portland Cement Concrete 18 8.11 Soil Corrosivity 18 9.0 LIMITATIONS OF INVESTIGATION 19 ILLUSTRATIONS Site Location Map Figure 1 Site Plan Figure 2 Fault Location Map Figure 3 Wall Drain Details Figure 4 Regional Seismicity Table 1 APPENDICES REFERENCES Appendix A FIELD EXPLORATION Appendix B LABORATORY TESTING Appendix C Geotechnics Incorporated REPORT OF GEOTECHNICAL INVESTIGATION LAGUNA POINT CONDOMINIUMS 539 LAGUNA DRIVE CARLSBAD, CALIFORNIA 1.0 INTRODUCTION This report presents the results of our geotechnical investigation for the proposed Laguna Point Condominium complex in Carlsbad, Califomia. We previously prepared a geotechnical report for a similar development over the westem half of the current site. That report was dated June 7,1999 (Project No. 0525-001 -00, Document No. 9-0484). The property has now been expanded to include the neighboring property to the east. Information from the previous report has been incorporated into and used in this report. The conclusions and recommendations of this report are based on our recent and previous subsurface exploration, review of our previous geotechnical report and other available geotechnical reports and plans, laboratory testing of select soil samples collected from the site, and our experience with similar soil and geologic conditions. 2.0 SCOPE OF SERVICES The purpose of our investigation was to evaluate the existing subsurface conditions at the site and provide recommendations for the geotechnical aspects of the proposed constmction. The scope of services provided for this project was described in our Proposal No. 1 -300, dated October 22,2001, Document No. 1-1209. Our scope of work included the following items: 1) Review of available site plans and geotechnical literature relevant to the project area. 2) Subsurface exploration of the eastem portion of the site using a tmck mounted, continuous flight, hollow stem drill rig. Five borings were drilled to depths of up to approximately 25 feet. Bulk and relatively undisturbed soil samples were collected for the geotechnical analysis. 3) Laboratory testing of selected soil samples in order to assess the pertinent physical characteristics of the foundation area soils. 4) Assessment of significant geologic hazards that may affect site development, including the effects of ground-shaking due to seismic events on nearby active faults. Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 2 5) Engineering analysis of field and laboratory data to provide recommendations regarding site preparation, earthwork and backfill, remedial earthwork, foundation and slab design parameters, soil bearing capacities, foundation settlement potential, retaining wall design, slope stability, concrete pavement design, and site drainage and moisture protection. 6) Preparation of a report summarizing our current and previously reported findings, conclusions and recommendations. 3.0 SITE DESCRIPTION The subject site is located on the south side of Laguna Drive between State Street and Roosevelt Street in Carlsbad, Califomia, as shown on the Site Location Map, Figure 1. The west half of the site appears to have been previously developed, however, there are no stmctures currently at the site. The west half of the site is overlain with old asphalt and concrete pavement. A retaining wall having a maximum height of about 5Y2 feet is located on the northwest comer of the site. The east half of the site is un-surfaced. Current site elevations vary from about 40 feet above mean sea level (MSL) at the northwest comer to about 42 feet MSL at the east end. An underground fuel storage tank was reportedly located on the northwest comer of the site. It is our understanding that the storage tank was removed and that an environmental report was issued at completion of the removal and associated cleanup. 4.0 PROPOSED CONSTRUCTION We understand that the proposed development will consist of two, three-story buildings with the lower at-grade level comprising a parking garage. The two buildings (designated A & B for reference purposes) will be coimected by a relatively narrow, three-story building with a lobby on the lower level. We anticipate that wood framing with conventional slabs-on-grade and shallow foundations will be used. The proposed buildings will be constructed at approximate current elevations. Asphalt and concrete paving is anticipated in the driveways and parking garages. A pool Geotechnics Incorporated 0.5 Miles Reference: Tiiomas Brothers Guide 2002. Geotechnics Incorporated SITE LOCATION MAP ProjectNo. 0703-001-00 Document No. 1-1248 FIGURE 1 Rev. 6/99 WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAQE 3 is proposed on the south side of Building B. The site layout, with the proposed constmction, is shown in relation to our exploratory borings on the Site Plan, Figure 2. 5.0 GEOLOGY AND SUBSURFACE CONDITIONS The site is located on a broad mesa within the Peninsular Ranges Geomorphic Province of Califomia. This province extends from the Los Angeles basin to the tip of Baja Califomia, and is characterized by a series of northwest trending mountain ranges separated by sub-parallel fault zones, and a coastal plain of subdued landforms. The mountain ranges are underlain primarily by Mesozoic metamorphic rocks that were intmded by plutonic rocks of the southem Califomia batholith. The coastal plain is underlain by subsequently deposited marine and nonmarine sedimentary formations. Specifically, the site is underlain by fill, residual soil. Bay Point Formation, and Santiago Formation. The approximate locations of the exploratory borings drilled for this investigation are shown on the Site Plan, Figure 2. Logs ofthe borings are provided in Appendix B. Generalized descriptions of the units observed, from oldest to youngest, are as follows: 5.1 Santiago Formation The Santiago Formation was encountered in Borings B-8, B-10, B-l 1, and B-12 at a depth of approximately 17-1/2 to 18-1/2 below ground surface. The formation typically consists of very dense, silty, fine to medium grained sandstone, and clayey sandstone with interbedded claystone. 5.2 Bay Point Formation The Quatemary aged Bay Point Formation underlies the entire site at depth and was encountered in most of the borings at depths varying between about 2 to 12 feet. The Bay Point Formation was observed to consist of sand, clayey sand and sandy clay. The sand varied between silty (SM) and poorly graded (SP), orangish brown, yellow brown, and gray in color, fine to coarse grained, and medium dense to very dense. Some ofthe sands had low to moderate cementation. The clayey sand (SC) was orangish brown, medium to coarse Geotechnics Incorporated LAGUNA DRIVE r \ 'f^^ C^. >'\ 4 K \ \ SCALE: 1" = 40' EXPLANATION Indicates boring number and approximate location Reference: LagunaPt-9-21-01Site-for-eng.dwg, provided by McGee Behun Architects, 2001. o CO CN 001-0 1-124 URE CO O o h-z Ll. o c d z E o O o o Q Q_ GL LU CO WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 4 grained, and dense to very dense. A layer of fat sandy clay (CH) was observed in one of our borings. The sandy clay was olive gray with a high plasticity, and was observed to be firm. 5.3 Residual Soil Residual soil was encountered in all of the new borings on the east half ofthe site and at four of our borings below the old asphalt concrete and gravel at the west half of the site. The residual soil consists of brown to dark brown silty and poorly graded sand (SM and SP). The sand is fine to medium grained, and loose to very dense. 5.4 Fill Fill soils were encountered in several of the borings on the west side of the site (B-2, B-4, B-7, and B-8). The fill soils consist of clayey sand and sand and extended to a depth of about 17 feet below existing grade. The sand and clayey sand are brown to orangish brown, fine to medium grained, and dense. Some gravel and cobbles were encountered in our borings. The fill soils appear to be derived from the underground tank removal activities as well as previous undocumented fill activities. Black staining was observed in some of the fill materials, and hydrocarbon odor was observed in Boring B-8. The odor was observed after completion of the boring, prior to backfill. 5.5 Groundwater Groundwater was encountered in Borings B-3, B-8, and B-10 at a depth of about 17'/2 to 20 feet below existing grade. The groundwater is likely perched above the contact between the Bay Point and Santiago Formations. Changes in rainfall, irrigation, site drainage or leaks in a utility line could cause the groundwater level to fluctuate. It should be recognized that excessive irrigation on the project site could also result in increases to the existing perched groundwater at some future date. Since the prediction of the location of such conditions is not possible, they are typically mitigated if and when they occur. Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO. 1-1248 DECEMBER 17, 2001 PAGE 5 6.0 GEOLOGIC HAZARDS AND SEISMICITY The subject site is not located within an area previously known for significant geologic hazards. Evidence of past soil failures, landslides, or active faulting on the site was not encountered. The geologic hazard that would most likely affect the site is ground shaking due to earthquakes on regional active faults. Existing and potential geologic hazards at the site are as follows: 6.1 Seismicity Based on the computer program TOPO! (Wildflower Productions, 1997), the subject site is located at an approximate latitude of 33.16° north, and an approximate longitude of 117.35° west. The computer program EQFAULT (Blake, 1998) was used to estimate peak horizontal accelerations from regional faults. The nearest known active fault is the Newport-Inglewood Offshore Fault located approximately 4.5 miles (7.3 km) west of the site. Table 1 presents a summary of the Regional Seismicity of faults within a 62 mile (100 km) radius of the site. The Fault Location Map, Figure 3, shows the general location of the site in relation to active and potentially active faults in southem Califomia. The program FRISKSP (Blake, 1998) was used to perform a probabilistic analysis of seismicity at the subject site based on the characteristic earthquake distribution of Youngs and Coppersmith (1985) and an attenuation relationship for Rock/Stiff Soil (Idriss, 1994). Based on the results of the probabilistic analysis, the Design Basis Earthquake produces a ground acceleration of 0.32g (10 percent probability of being exceeded in a 50-year period; 475 year retum period). 6.2 Ground Rupture Ground mpture is the result of movement on an active fault reaching the surface. There are no known surface expressions of active faults underlying the site or projecting toward the site. In our opinion, the probability of surface rupture due to faulting beneath the site is considered low. However, lurching and ground cracking are a possibility as a result of a significant seismic event on a nearby active fault. Geotechnics Incorporated DISTANCE MAX. CRED.* MAX. CRED.* ESTIMATED ESTIMATED ESTIMATED FAULT' TO SITE DETERMINISTIC MOMENT FAULT AREA-* SHEAR MOD.'' SLIP RATE"* [KM] PGA^ MAGNITUDE^ [CM^] [DYNE/CM''] [MM/YEAR] Newport-Inglewood (Offshore) 7 0.41 7.1 1.60E+13 3.30E+11 1.20 Rose Canyon 7 0.40 7.0 1.13E+13 3.30E+11 1.50 Coronado Banks-Agua Bianca 33 0.18 7.5 5.78E+13 3.30E+11 3.00 Elsinore 39 0.15 7.5 3.00E+13 3.30E+11 5.00 La Nacion^ 41 0.10 6.5 4.76E+12 3.30E+11 0.05 San Diego Trough-Bahia Sol. 49 0.12 7.5 3.00E+13 3.30E+11 2.00 Catalina Escarpment 56 0.08 7.0 2.55E+13 3.30E+11 1.00 Palos Verdes Hills 65 0.08 7.2 1.30E+13 3.30E+11 3.00 Compton-Los Alamitos 71 0.19 7.2 1.11E+13 3.60E+11 1.40 Chino 73 0.07 7.0 5.95E+12 3.30E+11 1.00 San Jacinto (Casa Loma-Clark) 76 0.05 7.0 1.50E+13 3.30E+11 12.00 Whittier - North Elsinore 80 0.05 7.1 8.15E+12 3.30E+11 3.00 San Jac. (Hot Springs-Buck Ridge) 81 0.05 7.5 1.53E+13 3.30E+11 10.00 San Jacinto (Coyote Creek) 83 0.05 7.0 6.00E+12 3.30E+11 4.00 San Clemente-San Isidro 88 0.09 8.0 6.00E+13 3.30E+11 4.00 San Gorgonio-Banning 96 0.07 7.5 1.53E+13 3.30E+11 10.00 1. Fault activity determined by Blake (1998), CDMG (1992), Wesnousky (1986), and Jennings (1975). 2. Peak horizontal ground accelerations from Idriss (1994) for Rock or Stiff Soil Sites for the Maximum Credible Earthquake. 3. Magnitudes determined from Blake (1998), OSHPD (1995), Mualchin and Jones (1992), Wesnousky (1986) and Anderson (1984). 4. Estimated fault area, shear modulus, and slip rate after fault data for EQFAULT and FRISKSP, Blake (1998). 5. The La Nacion is considered to be "Potentially Active", and does not apply to noncritical structures. 6. The Maximum Credible Earthquake is defined as the maximum earthquake that appears capable of occurring under the known tectonic framework. Geotechnics Incorporated REGIONAL SEISMICITY Project No. 0703-001-00 Document No. 1-1248 TABLE 1 0 10 20 30 40 50 60 SCALE Modified from Anderson, Rockwell, Agnew, 1989 Geotechnics Incorporated FAULT LOCATION MAP Project No. 0703-001-00 Document No. 1-1248 FIGURE 3 \Drafting\CorelDraw\Fault Rev. 10/00 WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 pAQE 6 6.3 Liquefaction and Dynamic Settlement Liquefiable soil typically consists of cohesionless sands and silts that are loose to medium dense, and saturated. To liquefy, these soils must be subjected to ground shaking of sufficient magnitude and duration. The soil profile at the developed site will consist of medium dense to dense materials. Considering the dense nature ofthe soil at the developed site, and the absence of a shallow groundwater level, we consider that the potential for liquefaction to occur is negligible. 6.4 Subsidence The subject site is not located within an area known for fluid extraction (oil, gas, or water), nor is the area knovra for past cases of subsidence due to fluid removal. It is our opinion that subsidence due to the extraction of fluids is remote. 6.5 Landslides and Lateral Spreads The site or other landslides to occur at the site is remote. 6.6 Tsunamis, Seiches, Earthquake Induced Flooding ...V. oite topography is relatively flat. The graded site will not contain bluffs, steep slopes, or other topographic features susceptible to landslides. Accordingly, the potential for Due to the site's elevation above sea level (approximately 40 feet), the potential for tsimamis to impact the site is considered remote. There are no dams located upstream ofthe site and the site is not located within a FEMA flood plain. Accordingly, we consider the potential for earthquake-induced flooding to be low. 7.0 CONCLUSIONS Based on the results ofthis investigation, it is our opinion that the proposed constmction is feasible from a geotechnical standpoint provided the following recommendations and appropriate Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 7 constmction practices are followed. Geotechnical design and constmction considerations include the following: There are no known active faults underlying the proj ect site. Potential seismic hazards at the site will likely be associated with ground shaking from seismic events along regional active faults. The nearest knovra active fault is the Newport Inglewood Offshore Fault located approximately 4.5 miles (7.3 km) west of the site. This hazard is typically mitigated through design in accordance with the Uniform Building Code. The existing undocumented fill materials below the west end of the proposed Building A footprint are not suitable to support loads from fill or structures. We recommend that these materials be removed, and replaced as compacted fill. After recompaction of the fill materials, a transition from medium dense fill to very dense formational materials will be present below the Building A footprint. Transitions below building foundations and slabs are not recommended due to the potential for adverse differential settlement. In order to reduce this potential, we recommend that an undercut should be completed below the east side of the Building A pad. • The variation in the consistency of the existing residual soil below the proposed Building B pad is such that adverse differential settlement may occur if the building foundations are set on this material. In order to decrease the potential of differential settlement, residual soil within 4 feet of the underside ofbuilding foundations should be removed and recompacted. The on-site fill, residual soil, and formational materials are, in general, suitable for re-use in compacted fills. Any trash, demolition debris, or organic material encountered is considered unsuitable for re-use in compacted fills. Clays having an Expansion Index greater than 50 are not suitable for placement within the upper 5 feet of finished grade. Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO. 1-1248 DECEMBER 17,2001 PAGE 8 8.0 RECOMMENDATIONS The remainder of this report presents recommendations regarding earthwork construction for the proposed improvements, as well as geotechnical recommendations for the design of the proposed pavement and stmctures. These recommendations are based on empirical and analytical methods typical ofthe standard-of-practice in southern Califomia. If these recommendations appear not to address a specific feature of the project, please contact our office for additions or revisions to the recommendations. 8.1 Plan Review It is recommended that foundation and grading plans be reviewed by Geotechnics Incorporated prior to plan finalization. Significant changes in the proposed constmction from the preliminary information used for this investigation may require additional geotechnical evaluation. 8.2 Grading and Excavation Observation Foundation excavations and site grading should be observed by a qualified geotechnical consultant. During grading, Geotechnics Incorporated should provide observation and testing services continuously. Such observations are considered essential to identify field conditions that differ from those anticipated from the geotechnical investigation, to adjust designs to actual field conditions, and to determine that the grading is accomplished in general accordance with the geotechnical recommendations. Geotechnics Incorporated should perform sufficient testing of fill during grading to support a professional opinion as to compliance with compaction recommendations. 8.3 Earthwork Earthwork is anticipated to include excavation and recompaction of up to approximately 17- 1/2 feet of fill and residual soils, excavations for foundations, temporary excavations for underground utilities, and placement of fill and backfill. Grading and earthwork should be conducted in accordance with the applicable local grading ordinances, and the 1997 Uniform Building Code. The following recommendations are provided regarding specific aspects of Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 pAGE 9 the proposed earthwork construction. These recommendations should be considered subject to revision based on field conditions observed by the geotechnical consultant during grading. 8.3.1 Site Preparation General site preparation should include clearing and gmbbing, removal of existing asphalt, concrete foundations or other improvements from areas that will be subjected to structural or fill loads. Clearing and grubbing should consist of the removal of vegetation including brush, grass, weeds, wood, stumps, trees, tree roots, and otherwise deleterious materials from areas to be graded. Unsuitable materials include vegetation, trash, constmction debris, topsoil, rocks more than 6 inches in greatest dimension, contaminated soils, soils subject to bio-degradation, or other undesirable materials. Building A To reduce the potential for differential settlement beneath the pad at Building A, we recommend that the existing undocumented fill materials at the west end of the building be removed and replaced as compacted fill, and that an undercut of 8 feet below the remaining Building A footprint should be completed. If desired, the undercut below the eastem one-third of Building A could be reduced to 4 feet. The recommended undercut depth is the depth below the underside of footing. Based on our investigation, the maximum thickness of undocumented fill is approximately 17'/2 feet. The base of the over-excavation in the undocumented fill area should extend horizontally at least five feet beyond the building perimeter, and formational soils should be exposed at the base of the over-excavation. The excavation of the undocumented fill and the 8 foot undercut should be replaced with fill material consisting ofapproved on-site or imported soil with an expansion index less than 50. feet beyond the proposed building area. The lateral extent of the remedial excavations should be determined during grading based on observations made by the geotechnical consultant. Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 10 As an altemative to recompacting the fill below Building A, the building could be supported on piers and footings founded in formational materials. This option is discussed further in Section 8.7. Building B and Lobby To reduce the potential for differential settlement beneath the pad at Building B, and the attached lobby, we recommend that the upper 4 feet of existing residual soil below the underside of foundations be excavated and replaced as compacted fill. The zone of excavation and recompaction should extend horizontally at least five feet beyond the building perimeter. Parking/Driveway Areas To provide a relatively uniform bearing surface for the parking and driveway areas, we recommend that the upper 2 feet of existing residual soil below the underside of the pavement section be excavated and replaced as compacted fill. 8.3.2 Fill Compaction All fill and backfill should be placed at slightly above optimum moisture content using equipment that is capable of producing a uniformly compacted product throughout the entire fill lift. Fill materials at less than optimum moisture should have water added and the fill mixed to result in material that is uniformly above optimum moisture content. Fill materials that are too wet should be aerated or mixed with drier material to achieve uniformly moisture-conditioned soil. The fill and backfill should be placed in horizontal lifts at a thickness appropriate for the equipment spreading, mixing, and compacting the material, but generally should not exceed 8 inches in loose thickness. In general, the minimum relative compaction recommended for fill and backfill is 90 percent of maximum dry density based on ASTM D1557 guidelines. The upper one foot of subgrade in asphalt parking and driveway areas should be compacted to at least 95 percent of maximum dry density just prior to constructing the pavement section. Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 11 8.3.3 Fill Materials In general, the on-site materials may be used in fills, with the exceptions noted below. Deleterious materials, rocks more than 6 inches in greatest dimension, and contaminated soils should not be used. Soils having an Expansion Index of greater than 50 should not be placed within the upper 4 feet of finish building subgrade or within the upper 2 feet of finish hardscape subgrade. Soils with an Expansion Index of greater than 20 should not be used as wall backfill. Imported fill sources (if required) should be observed prior to hauling onto the site to determine their suitability for use. Representative samples of imported materials and on-site soils should be tested to evaluate their engineering properties for the planned use. During grading operations, soil types other than those evaluated in the geotechnical report may be encountered by the contractor. The Geotechnics Incorporated should be notified to evaluate the suitability of these soils for use as fill and as finish grade soils. 8.4 Temporary Excavations Temporary excavations may be made during excavation of fill materials and during constmction of underground utilities. Such excavations are expected to be generally stable provided they are properly laid back or shored. Temporary excavations up to 3 feet may be vertical. Temporary excavations up to 20 feet deep should be laid back no steeper than 1:1 (horizontaLvertical), or shored, prior to allowing workers to enter. Based on the site plan provided to us and our investigation, temporary excavation slopes required for removal and recompaction of fill may extend beyond the property lines. If this is the case, permission to encroach beyond the property line should be obtained. Temporary excavations that encounter seepage or other potentially adverse conditions should be evaluated by the geotechnical consultant during grading. Remedial measures may include shoring or reducing slope inclinations. Groundwater was encountered during drilling and is anticipated at the base of the deepest excavation for the recompaction of the fill. The bottom should be dewatered sufficiently to provide a stable working surface. Cmshed rock or lean concrete may be placed to provide a working surface. Water which accumulates in the base ofthe excavation may be removed by the use of sumps. Filter fabric should be placed over Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 pAQE 12 the top of the cmshed gravel to prevent finer fill material from migrating into the voids which may result in ground settlement. All excavations should conform with Cal-OSHA guidelines, and workmen should be protected from unstable excavation walls or falling objects in accordance with Cal-OSHA requirements. 8.5 Lateral Pressures on Shoring For temporary excavations that will be shored, but not braced with tiebacks or struts, we recommend using a triangular pressure distribution for calculating earth pressures. Shoring design may be based on an equivalent fluid pressure of 35 lbs/ft^ for granular materials, plus any groundwater pressures encountered in the excavation and any surcharge loads resulting from loads placed above the excavation and within a 1:1 plane extending upward from the base ofthe excavation (estimated safety factor of 1). Should surcharge loads be anticipated, or braced shoring be used, Geotechnics Incorporated should be contacted to provide additional design parameters. 8.6 Surface Drainage Foundation and slab performance depends greatly on how well the runoff waters drain from the site. This is true both during constmction and over the entire life ofthe stmcture. The ground surface around stmctures should be graded so that water flows away from the stmctures without ponding. The surface gradient needed to achieve this depends on the prevailing landscape. In general, we recommend that pavement and lawn areas within 5 feet of buildings or pavement slabs slope away at gradients of at least 2 percent. Densely vegetated areas should have minimum gradients of at least 5 percent away from buildings in the first 5 feet. Densely vegetated areas are considered those in which the planting type and spacing are such that the flow of water is impeded. Planters should be built so that water from them will not seep into the foundation, slab, or pavement areas. Roof drainage should be channeled by pipe to storm drains, discharged to paved areas draining offsite, or discharged at least 10 feet from building lines in landscaped areas. Site irrigation should be limited to the minimum necessary to sustain landscaping plants. Should excessive irrigation, surface water intmsion, water line breaks, or unusually Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 13 high rainfall occur, saturated zones or "perched" groundwater may develop in the underlying soils. 8.7 Foundation Recommendations These recommendations are considered generally consistent with methods typically used in southem Califomia. Other altematives may be available. The foundation recommendations contained herein should not be considered to preclude more restrictive criteria of goveming agencies or the stmctural engineer. Foundation dimensions and reinforcement values provided herein are minimum criteria based on geotechnical concems and should not be considered a structural design. The design of the foundation system should be performed by the project structural engineer, incorporating the geotechnical parameters described in the following sections. The following design parameters assume that the foundations will consist of continuous or spread footings bearing entirely on compacted fill material having a low expansion potential (Expansion Index of 50 or less). A one-third increase in the allowable bearing pressure may be used for short-term wind or seismic loads. Allowable Soil Bearing: 2,000 psf Minimum Footing Width: 18 inches Minimum Footing Depth: 24 inches below lowest adjacent soil grade. Minimum Reinforcement: Two No. 4 bars at both top and bottom in continuous footings. Anticipated Settlement: 1-inch total, and y4-inch differential settlement over 40 feet. Lateral loads may be resisted by frictional resistance and by the passive resistance ofthe compacted fill materials. A coefficient of friction of 0.35 may be used between the bottom of footings and the compacted fill materials. The passive resistance may be assumed to be equal to the pressure developed by a fluid with a density of 350 lbs/ft^ for the portion of vertical foundation members embedded into compacted fill A one-third increase in the Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 14 passive values may be used for wind or seismic loads. The passive resistance of the materials may be combined with the frictional resistance without reduction in evaluating the total lateral resistance. Deep Foundation Option - Building A As an altemative to removing and recompacting the fill below Building A, the building could be supported on piers and footings founded on formational material. Driven piles may not be suitable due to the presence of very dense layers with the fill. In areas where the depth to formational material is relatively shallow (B-l, B-3, B-5, and B-6), The minimum foundation depth should extend at least 4 feet into the formational unit due to the presence of less dense layers within the upper several feet of the Bay Point Formation. The allowable bearing pressure for foundations in formational material is 3,000 psf With this option, we recommend that the upper 3 feet of the subgrade below the parking slab should be recompacted. Cracking in the parking slab may occur as a result of settlement of the undocumented fill. To reduce the potential for slab cracking, the control joint spacing could be reduced to 5 feet, and/or the slab could be reinforced. If this option is used, there is a potential for relatively abrupt movement at the location where the lobby joins Building A. Differential movements could be in the range of approximately one-half inch at this area. The structural design of the building should allow for these anticipated movements. Because of the potential for differential movements, we consider that the recompaction option discussed previously is the preferred method. We should be contacted to provide additional design parameters for the pier foundations if this is the chosen option. 8.7.1 Site Seismic Parameters The following seismic parameters, based on the 1997 Uniform Building Code, may be used for design of the proposed stmctures: Seismic Zone Factor, Z: 0.4 Seismic Source Type: B Soil Proflle Type: S^. Seismic Coefficients, C„: O AN^ C- 0.56K. Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 pAGE 15 Near-Source Factors, N^: 1.0 N- 1.1 8.8 On-Grade Slabs Slabs should be designed for the anticipated loading. If an elastic design is used, a modulus of subgrade reaction of 200 lbs/in^ may be used. Slab thickness and reinforcement should be designed by the project stmctural engineer and should conform to the requirements ofthe 1997 UBC. We recommend that building slabs be at least 5 inches in thickness and be reinforced with at least No. 3 bars placed on chairs and spaced 18 inches on center, each way at slab mid-height. 8.8.1 Moisture Protection for Interior Slabs Concrete slabs constmcted on soil ultimately cause the moisture content to rise in the underlying soil. This results from continued capillary rise and the termination of normal evapo-transpiration. Because normal concrete is permeable, the moisture will eventually penetrate the slab. Excessive moisture may cause mildewed carpets, lifting or discoloration of floor tile, or similar problems. To decrease the likelihood of problems related to damp slabs, suitable moisture protection measures should be used where moisture sensitive floor coverings or other factors warrant. A commonly used moisture protection in southem Califomia consists of about 2 inches of clean sand covered by 10-mil polyethylene plastic sheeting. In addition, 2 inches of clean sand are placed over the plastic to decrease concrete curing problems associated with placing concrete directly on an impenneable membrane. It has been our experience that such systems will transmit from approximately 6 to 12 pounds of moisture per 1000 square feet per day. This may be excessive for some applications, particularly for wood flooring or sheet vinyl, vinyl tiles, or carpeting with impermeable backing that use water soluble adhesives. For example, moisture sensitive floor coverings such as vinyl may develop discoloration or adhesive degradation due to excessive moisture transmission. Wood flooring may swell and dome if exposed to excessive moisture transmission. In such cases, the architect Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 16 should specify an appropriate moisture barrier based on the allowable moisture transmission rate for the flooring to be used. 8.8.2 Exterior Slabs Exterior slabs should be at least 4 inches thick and should be reinforced with at least 6-inch by 6-inch, W2.9 by W2.9 welded wire fabric placed at slab mid-height. Crack control joints should be used on all exterior slabs, with a maximum spacing of 5-foot centers each way for sidewalks and 10-foot centers each way for slabs. Differential movement between sidewalks and curbs or structures may be decreased by doweling the slab into the curb and/or structure. 8.9 Earth Retaining Structures For cantilever retaining walls backfilled with granular soils, where the backfill is level or nearly level, an active earth pressure approximated by an equivalent fluid pressure of 35 lbs/ft^ may be used. The active pressure should be used for walls free to yield at the top at least 0.2 percent ofthe wall height. Where the earth slopes upwards at 2:1, an equivalent fluid pressure of 50 lbs/ft^ should be used. For walls restrained so that such movement is not permitted, an equivalent fluid pressure of 55 lbs/ft^ should be used, based on at-rest soil conditions with level backfill. In addition to the recommended earth pressure, walls adjacent to vehicular traffic should be designed to resist a uniform lateral pressure of 100 lbs/ft^ acting as a result of an assumed 300 lbs/ft^ surcharge behind the wall. Ifthe traffic is kept back at least 10 feet from the walls, the traffic surcharge may be neglected. Lateral loads on retaining walls may be resisted by friction and by the passive resistance of the supporting soils in front of the wall. For retaining walls, a coefficient of friction of 0.35 may be used between the bottom of footings and the compacted fill. The passive resistance of compacted fill may be assumed to be equal to the pressure developed by a fluid with a density of 350 lbs/ft^ for the portion of vertical foundation members embedded into compacted fill. The above pressures assume no hydrostatic pressures, which will increase the lateral pressures on the wall. Geotechnics Incorporated should be contacted for additional Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17, 2001 PAGE 17 recommendations if hydrostatic pressures are applicable. Walls should contain an adequate subdrain to reduce hydrostatic forces. Wall drain details are presented in Wall Drain Details, Figure 4. Backfilling retaining walls with expansive soils can increase lateral pressures well beyond the active or at-rest pressures indicated above. We recommend that retaining walls be backfilled with free draining, cohesionless soil having an Expansion Index of 20 or less. In general, most ofthe on-site soils observed during our investigation with the exception of the clayey sand and sandy fat clay are considered suitable for use as wall backfill materials. The backfill area should include the zone defined by a 1:1 plane, sloping upward from the heel ofthe wall. Retaining wall backfill should be compacted to at least 90 percent relative compaction, based on ASTM D1557. Backfill should not be placed until walls have achieved adequate structural strength. Heavy compaction equipment which could cause distress to walls should not be used. 8.10 Pavement Prior to paving the site, the exposed pavement subgrade should be scarified 12 inches, brought to approximately optimum moisture, and compacted. Aggregate base and the upper 12 inches of subgrade soil should be compacted to at least 95 percent ofthe maximum dry density, determined in general accordance with ASTM D1557. Aggregate base materials should conform with Class 2 aggregate base as defined in Section 26 ofthe latest edition of the Caltrans Standard Specifications. Altematively, base material may consist of crushed aggregate base as defined in Section 200-2.2 of the latest edition of the Standard Specifications for Public Works Constmction, ''Greenbook.'" Asphalt concrete should conform to Section 203-6 of the "Greenbook," and should be compacted to at least 95 percent of the Hveem unit weight. 8.10.1 Asphalt Concrete The paving sections for driveways and parking lots were established using the design criteria of Caltrans Topic 608.4. A Traffic Index (T.I.) of 5.0 was assumed for automobile parking and driveways. R-Value testing performed on a selected sample ofthe on-site soil indicates an R-Value of 61. Based on the criteria stated above, the Geotechnics Incorporated DAMP-PROOFING OR WATER- PROOFING AS REQUIRED ROCK AND FABRIC ALTERNATIVE MINUS 3/4-INCH CRUSHED ROCK ENVELOPED IN FILTER FABRIC (MIRAFI 140NL, SUPAC 4NP, OR APPROVED SIMILAR) 12-INCH MINIMUM 4-INCH DIAM. PVC PERFORATED PIPE DAMP-PROOFING OR WATER- PROOFING AS REQUIRED GEOCOMPOSITE PANEL DRAIN 1 CU. FT PER LINEAR FOOT OF MINUS 3/4-INCH CRUSHED ROCK ENVELOPED IN FILTER FABRIC 4-INCH DIAM. PVC PERFORATED PIPE PANEL DRAIN ALTERNATIVE WEEP-HOLE ALTERNATIVE NOTES 1) Perforated pipe should outlet through a solid pipe to a free gravity outfall. Perforated pipe and outlet pipe should have a fall of at least 1%. 2) As an alternative to the perforated pipe and outlet, weep-holes may be constructed. Weep-holes should be at least 2 inches in diameter, spaced no greater than 8 feet, and be located just above grade at the bottom of wall. 3) Filter fabric should consist of Mirafi 140N, Supac 5NP, Amoco 4599, or similar approved fabric. Filter fabric should be overlapped at least 6-inches. 4) Geocomposite panel drain should consist of Miradrain 6000, J-DRain 400, Supac DS-15, or approved similar product. 5) Drain installation should be observed by the geotechnical consultant prior to backfllling. Geotechnics Incorporated WALL DRAIN DETAILS ProjectNo. 0703-001-00 Document No. 1-1248 FIGURE 4 \Drafting\CorelDraw\Walldrn Rev. 6/99 y^^^^K,^ " PROJECT NO. 0703-001-00 ?7oS,^'?°°'^''^'^'^^ DOCUMENT NO. 1-1248 DECEMBER 17, 2001 PAGE 18 pavement section should consist of 3 inches of asphalt concrete over 4 inches of aggregate base. 8.10.2 Portland Cement Concrete Concrete pavement design was conducted in accordance with the simplified design procedure ofthe Portland Cement Association. This methodology is based on a 20 year design life. For design, it was assumed that aggregate interlock joints will be used for load transfer across control joints. Furthermore, the portland cement concrete was assumed to have a minimum 28 day flexural strength of 600 psi. A "medium" subgrade support (corresponding to a modulus of subgrade reaction between 130 to 170 pci) was assumed for design purposes. Based on these assumptions, we recommend that the pavement section consist of 5.5 inches of Portland cement concrete over native subgrade. Crack control joints should be placed on at least 10 foot centers, each way. Concentrated truck traffic areas, such as trash tmck apron, should be reinforced with at least number 4 bars on 18-inch centers, each way. 8.11 Soil Corrosivity Select soil samples were tested for water-soluble sulfate content in general accordance with ASTM test method D 516. The test results are reported in Appendix C in terms ofthe percentage by weight of the water soluble sulfate in the soil. The stmctural engineer for the project may use these test results in conjunction with Table 19-A-4 ofthe 1997 UBC in order to specify a suitable cement type, water cement ratio, and minimum compressive strength for concrete used on site which will be in direct contact with soil, including all foundations and slabs. The sulfate content test results presented in Appendix C represent the existing soil conditions at the site. Additional testing of the finish grade materials should be performed to evaluate the final as-graded condition of the site. It should be noted that soluble sulfate in the irrigation or wash water supply, and/or the use of fertilizer may cause the sulfate content in the surficial soils to increase significantly with time. This may result in a higher sulfate exposure than that indicated by the test results reported herein. Studies have shown that the use of improved cements in the concrete, and a low water-cement ratio will increase the resistance of the concrete to sulfate exposure. Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO. 1-1248 DECEMBER 17, 2001 PAGE 19 Select soil samples were tested for pH and resistivity in general accordance with Caltrans Test Method 643. Based on the resistivity test results, the on-site materials appear to be moderately corrosive to corrosive to ferrous metals. We recommend a Corrosion Engineer be retained to provide recommendations for the project. Select samples were tested for chloride content in general accordance with the Standard Method for Evaluation of Waste Water Test SMEWW4500CrC, which is conducted in general conformance with EPA Test Method 375.4. The test results are reported in Appendix C in terms of the percentage by weight of the chloride in the soil. Based on the chloride contents of the tested samples, the test results indicate that the corrosion potential of metals exposed to the on-site soils is negligible. 9.0 LIMITATIONS OF INVESTIGATION This report has been prepared for the exclusive use of Wave Crest Resorts II for specific application to the proposed Laguna Point Condominiums. The recommendations provided in this report are based on our understanding of the described project information and on our interpretation of the data collected during the subsurface exploration. The recommendations apply only to the specific project described in this report. In the event that any changes in the nature, design, or location of the facilities are plarmed from those described herein, the conclusions and recommendations contained in this report should not be considered valid unless the changes are reviewed and conclusions of this report modified or verified in writing by Geotechnics Incorporated. Geotechnics Incorporated is not responsible for any claims, damages, or liability associated with interpretation of subsurface data or reuse of the subsurface data or engineering analyses without the express written authorization of Geotechnics Incorporated. This investigation was performed using the degree of care and skill ordinarily exercised, under similar circumstances, by reputable geotechnical consultants practicing in this or similar localities. No other warranty, express or implied, is made as to the conclusions and professional opinions included in this report. The analyses and recommendations contained in this report are based on the data obtained from the referenced subsurface explorations. The samples taken and used for testing and the observations Geotechnics Incorporated WAVE CREST RESORTS II PROJECT NO. 0703-001-00 LAGUNA POINT CONDOMINIUMS DOCUMENT NO 1-1248 DECEMBER 17,2001 PAGE 20 made are believed representative of the locations sampled; however, borings indicate subsurface conditions only at the specific locations and times, and only to the depths penetrated. They do not necessarily reflect strata variations that may exist between such locations. Soil and geologic conditions can vary significantly between field explorations. The validity of the recommendations is based in part on assumptions about the stratigraphy made by the geotechnical engineer. Such assumptions may be confirmed only during construction operations. In many projects, conditions revealed by excavation may be at variance with preliminary findings. If this occurs, the changed conditions must be evaluated by Geotechnics Incorporated and additional recommendations made, if warranted. This report is issued with the understanding that it is the responsibility of Wave Crest Resorts II or of the designated representative, to ensure that the information and recommendations contained herein are brought to the attention of the design consultants for the project and incorporated into the plans, and the necessary steps are taken to see that the contractors carry out such recommendations in the field. Changes in the condition of a property can occur with the passage of time, whether due to natural processes or the work of man on this or adjacent properties. In addition, changes in applicable or appropriate standards of practice may occur from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of three years. During site preparation and foundation constmction, Geotechnics Incorporated should observe slab on-grade subgrades, and utility trench backfill to check compaction. The engineer should observe subgrade preparation beneath areas to be recompacted and observe and test fill compaction as required. The engineer should also observe building-foundation excavations to verify the presence of a firm bearing surface. Geotechnics Incorporated WAVE CREST RESORTS II LAGUNA POINT CONDOMINIUMS DECEMBER 17, 2001 PROJECT NO. 0703-001-00 DOCUMENT NO. 1-1248 PAGE 21 Geotechnics Incorporated should be retained to observe earthwork construction to help confirm that our assumptions and recommendations are valid or to modify them accordingly. Geotechnics Incorporated cannot assume responsibility or liability for the adequacy of recommendations if we do not observe construction. GEOTECHNICS INCORPORATED Maurice Amendolagine Project Engineer Anthony F. Belfast, P.E. 40333 Principal W. Lee Vanderhurst, C.E.G. 1125 Principal [<3t/ w. LEE \<5; VANDERHURST W>.^ No. 1125 CERTIFIED ENGINEERINO GEOLOGIST Geotechnics Incorporated APPENDIX A REFERENCES American Society for Testing and Materials, 1999, Annual Book of ASTM Standards, Section 4, Construction, Volumes 04.08 and 04.09, Soil and Rock; Geosynthetics: ASTM, Philadelphia, PA. Blake, T.F. (1998). EQFAULT, EQRISK, and FRISKSP: Computer Programs for the Estimation of Peak Horizontal Acceleration From Southem Califomia Historical Earthquakes. Califomia Division of Mines and Geology (1998). Maps of Known Active Fault Near-Source Zones in Califomia and Adjacent Portions of Nevada, Second Printing, Febmary. Geotechnics Incorporated (1999). Report of Geotechnical Investigation, Park Laguna Condominiums, Carlsbad, Califomia, ProjectNo. 0525-001-00, Document No. 9-0484, June 7, 1999. Geotechnics Incorporated (2001). Proposal for Geotechnical Services, Revised Geotechnical Investigation, Laguna Point Condominiums, Carlsbad, CA, Proposal No. 1-300, Document No. 1-209, October 22, 2001. Intemational Conference of Building Officials, 1997, Uniform Building Code (with California 1998 Amendments). Youngs, R.R. and Coppersmith, K.J. (1985). Implications of Fault Slip Rates and Earthquake Recurrence Models to Probabilistic Seismic Hazard Estimates, Bulletin ofthe Seismological Society of America, vol. 75, no. 4, pp. 939-964. Geotechnics Incorporated APPENDIX B FIELD EXPLORATION Our field explorations consisted of drilling 13 exploratory borings with a truck-mounted, 8-inch diameter hollow stem-auger drill rig. Our field exploration was performed on May 20, 1999, and November 6, 2001. The borings were advanced to a maximum depth of approximately 25-1/2 feet below existing grade. The approximate boring locations are shown on the Site Plan, Figure 2. Logs describing the subsurface conditions encountered are presented on Figures B-l through B-13. Standard penetration tests (SPTs) were performed in the borings. The number of blows (N value) is indicated on the boring logs. The SPTs were performed in general accordance with the ASTM Designation Dl 586 test method. The sampler used was a standard split-barrel sampler with an inside diameter of 1-3/8 inches and an outside diameter of 2 inches as described in the test method. The hammer used to drive the SPT sampler was a 140-pound hammer, and a drop of about 30 inches was used. The soil from the split spoon sample was collected in a sample bag for laboratory testing. Relatively undisturbed samples were also collected using a Califomia (CAL) sampler. The CAL sampler is a ring-lined tube with an inside diameter of 2-3/8 inches and an outside diameter of 3 inches. The ring samples were sealed in plastic bags, placed in rigid plastic containers, labeled, and retumed to the laboratory for testing. The number of blows needed to drive the CAL samplers 12 inches is shovra on the log. The CAL sampler was driven with the hammer described above. Bulk samples were also obtained at selected intervals. The approximate locations of the bulk and drive samples are indicated on the logs with shading. Boring locations were established in the field by taping distances from landmarks shovra on the referenced plans. The locations shovra should not be considered more accurate than is implied by the method of measurement used. The lines designating the interface between soil units on the boring logs are determined by interpolation and are therefore approximations. The transition between the materials may be abrupt or gradual. Further, soil conditions at locations between the borings may be substantially different from those at the specific locations explored. It should be recognized that the passage of time can result in changes in the soil conditions reported in our logs. Geotechnics Incorporated LOG OF EXPLORATION BORING NO. 1 Logged by: CW Date Drilled: 5/20/99 Method of Drilling: 8"-Diameter Hollow Stem Auger Elevation: 41' MSL c H U. Ul _i n UJ _l iZ° u DEPTH (P-BLOWS PEF DRIVE SAMI BULK SAMF DENSITY (P( MOISTURE 1 DESCRIPTION LAB TESTS Old asphalt concrete and gravel. — 1 RESIDUAL SOIL: Sand (SP). dark brown, fine moist, lnn.se tn mfiHiiim rifinsp — 2 BAY POINT FORMATION: Sand (SP) with silt, oranaish hrnwn tn gray — 3 10 CAL 116 8.3 medium, moist, medium dense. — 3 Layer of Fat sandy clay (CH), olive gray, moist, firm. — 4 — 5 — 6 Very dense. — 7 57 SPT — 8 o — y — 10 Orangish gray, friable. Gradation — 11 36 CAL — 12 — 13 Total depth: 12 feet — 13 No groundwater encountered — 14 No caving — 14 Backfilled: 5/20/99 — 15 — 16 — 17 — 18 — 19 — 20 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-1 Logged by: CW LOG OF EXPLORATION BORING NO. 2 8"-Diameter Hollow Stem Auger Date Drilled: 5/20/99 Elevation: 41' MSL DEPTH (FT) BLOWS PER FT DRIVE SAMPLE BULK SAMPLE DENSITY (PCF) MOISTURE (%) DESCRIPTION LAB TESTS Old asphalt concrete and gravel. — 2 FILL: Clavev sand to sand (SC-SP). oranaish brown, medium, moist, dense. — 2 Gravels and cobbles at 1 to IVi feet. — 3 — 4 32 SPT — 5 Consol. — 6 44 CAL 117 11.0 Black stains with hydrocarbon odor. — 7 — 8 Debris, plastic. — 9 — 10 — 11 30 SPT — 12 — 13 — 14 — 15 — 16 51 CAL 120 12.3 — 17 — 18 Refusal at 17 feet. — 17 — 18 Total depth: 17 feet — 17 — 18 No groundwater encountered — 19 No caving — 19 Backfilled: 5/20/99 — 20 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-2 Logged Method by: CW of Drilling: LOG OF EXPLORATION BORING NO. 3 8"-Dlameter Hollow Stem Auger Date Drilled: 5/20/99 Elevation: 42' MSL Q. UJ Q DESCRIPTION LAB TESTS - 8 - 9 • 10 - 11 • 12 • 13 • 14 15 16 17 18 19 20 Old asphalt concrete and gravel. RESIDUAL SOIL: Sand (SP), brown, medium, moist, loose to medium dense. some asphalt. 14 SPT 48 CAL 33 SPT 52 SPT BAY POINT FORMATION: Sand (SP), orangish brown, medium, moist, dense. 121 10.7 Clayey sand (SC), orangish brown, medium to coarse, moist, dense. Sand to clayey sand (SP-SC), orangish brown, medium to coarse, moist, very dense. Cobbles. V pH, Sulfate Resistivity Direct Shear Total depth: 18 feet Boring hole open for VA hours, water level measured at 17 feet No caving Backfilled: 5/20/99 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-3 LOG OF EXPLORATION BORING NO. 4 Logged by: CW Date Drilled: 5/20/99 Method of Drilling: 8"-Diameter Hollow Stem Auger Elevation 42' MSL DEPTH (FT) BLOWS PER FT ORIVE SAMPLE BULK SAMPLE DENSITY (PCF) MOISTURE (%) DESCRIPTION LAB TESTS 6" Old asphalt concrete. — 1 FILL: Clayey sand (SC), brown to orangish brown, fine to medium, moist, Expansion — 2 — 3 — 4 dense, gravels and cobbles. Index — 2 — 3 — 4 74 CAL 126 9.4 — 5 —_ Q — 7 — 8 30 SPT — 9 Dark brown. — 10 — 10 Gradation — 11 36 CAL BAY POINT FORMATION: Sand fSP^ with silt, liaht tn meriium nranrjish — 11 brown, fine, moist, dense, friable. — 12 — 13 — 14 — 15 Sand (SP), light gray to orangish gray, coarse, moist, very dense, some — 15 cobbles. — 16 53 SPT — 17 — 18 Total depth: 17 feet — 18 No groundwater encountered — 19 No caving — 19 Backfilled: 5/20/99 — 20 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-4 Logged by: CW Method of Drilling: LOG OF EXPLORATION BORING NO. 5 Date Drilled: 5/20/99 8"-Diameter Hollow Stem Auger Elevation: 43' MSL DEPTH (FT) BLOWS PER FT DRIVE SAMPLE BULK SAMPLE DENSITY (PCF) MOISTURE (%) DESCRIPTION LAB TESTS 4" Old asphalt concrete. — 1 RESIDUAL SOIL: Sand (SP). dark oranaish brown, fine, moist, medium dense. — 2 — 3 18 CAL 111 5.2 BAY POINT FORMATION: Sand (SP). oranaish brown, fine to medium, moist — 4 medium dense. — 5 — 6 — 7 28 SPT — 8 q — 10 Sand (SP) with silt, orangish brown, fine to medium, moist, dense. — 11 67 CAL 118 5.5 — 12 — 13 — 14 — 12 — 13 — 14 Total depth: 12 feet No groundwater encountered No caving Backfilled: 5/20/99 — 15 — 16 — 17 — 18 — 19 — 20 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-5 LOG OF EXPLORATION BORING NO. 6 Logged by: CW Date Drilled 5/20/99 Method of Drilling: 8"-Diameter Hollow Stem Auger Elevation: 42' MSL DEPTH (FT) BLOWS PER FT DRIVE SAMPLE BULK SAMPLE DENSITY (PCF) MOISTURE (%) DESCRIPTION LAB TESTS 4" Old asphalt concrete over 4" base. — 1 RESIDUAL SOIL: Sand (SP). dark brown, fine, moist, medium dense. — 2 — 3 BAY POINT FORMATION: Sand (SP). dark oranaish brown, fine, moi.st — 5 medium dense. — 6 — 7 17 SPT — 8 — 9 — 10 Orangish gray to orangish brown. — 11 45 CAL 108 5.8 — 12 — 13 — 12 — 13 Total depth: 12 feet — 12 — 13 No groundwater encountered — 14 No caving — 14 Backfilled: 5/20/99 — 15 — 16 — 17 — 18 — 19 — 20 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-6 LOG OF EXPLORATION BORING NO. 7 Logged by: CW Date Drilled: 5/20/99 Method of Drilling: 8"-Diameter Hollow Stem Auger Elevation: 41'MSL DEPTH (FT) BLOWS PER FT DRIVE SAMPLE BULK SAMPLE DENSITY (PCF) MOISTURE (%) DESCRIPTION LAB TESTS — 2 — 3 FILL: Clayey sand to sand (SC-SP), brown, fine to medium, moist, medium — 2 — 3 dense, abundant gravels and cobbles. — 4 — 5 — 6 — 7 Olive green to grayish brown. — 8 — 9 — 10 — 11 — 12 — 13 Refusal at 12 feet. — 12 — 13 Total depth: 12 feet — 12 — 13 No groundwater encountered — 14 No caving — 14 Backfilled: 5/20/99 — 15 — 16 — 17 — 18 — 19 — 20 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-7 Logged by: CW Method of Drilling: LOG OF EXPLORATION BORING NO. 8 Date Drilled: 5/20/99 8"-Diameter Hollow Stem Auger Elevation: 41' MSL DEPTH (FT) BLOWS PER FT DRIVE SAMPLE BULK SAMPLE DENSITY (PCF) MOISTURE (%) DESCRIPTION LAB TESTS — 2 — 3 FILL: Sand to clavev sand (SP-SC). oranaish brown, fine to medium, moi.st, dense. Abundent gravels and cobbles. — 4 — 5 Olive to grayish brown. — 6 — 7 Asphalt pieces. — 8 — Q — y 10 — 11 Debris, plastic. — 12 — 13 — 12 — 13 BAY POINT FORMATION: Sand (SP). liaht vellowish brown, fine, moist. — 12 — 13 dense. — 14 — 15 — 16 — 17 — 18 SANTIAGO FORMATION: Sand (SP). liaht arav with olive tint, coarse, moist. — 18 very dense. — 19 90 48/6" SPT / Total depth: 20 feet / Groundwater encounterd at 1 TA feet / No caving Backfilled: 5/20/99 Hydrocarbon odor obsen/ed in boring after drilling completed PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-8 LOG OF EXPLORATION BORING NO. 9 Logged by: MA Date Drilled: 11/6/01 Method of Drilling: 8-inch diameter hollow-stem auger Elevation: +/- 43' MSL P UL X I-a Ul o oc tii a. tn I -I OQ u. O t tn z Ul Q Ul CL tn O s DESCRIPTION LAB TESTS 1 - 2 - 3 - 4 - 5 6 7 8 - 9 - 10 - 11 - 12 - 13 - 14 15 16 - 17 - 18 - 19 - 20 21 22 23 24 25 28 21 23 22 SPT SPT SPT SPT RESIDUAL SOIL: Silty sand (SM), brown, fine to medium, medium dense, moist R-Value BAY POINT FORMATION: Silty sand (SIVI), orange-brown, fine to medium, medium dense, moist medium dense Poorly graded sand (SP), tan to orange-brown, fine to coarse, moist Total Deptti: 16-1/2 feet No Groundwater Backfilled: 11/6/01 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-9 LOG OF EXPLORATION BORING NO. 10 Logged by: MA Date Drilled: 11/6/01 Method of Drilling: 8-inch diameter hollow-stem auger Elevation: +/- 43' MSL cc til a. tn I -I CO CJ Q. CO z Ul Q Ul OC D 1-CO o S DESCRIPTION LAB TESTS - 1 - 2 - 3 - 4 - 5 - 6 7 - 8 - 9 - 10 - 11 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 20 21 22 23 24 25 SPT 36 SPT 23 CAL 49 SPT 25 SPT 47 CAL 87 RESIDUAL SOIL: Silty sand (SM), brown, fine to medium, dense trace caliche, weak cementation, dry medium dense Sulfate pH Resistivity Ctiloride 108 7.0 BAY POINT FORMATION: Silty sand (SIVI), yellow-brown to orange, fine to coarse, dense, weak to moderate cementation, moist Poorly graded sand (SP), medium dense, moist V Groundwater at 20 feet SANTIAGO FORMATION: Clayey sandstone (SC), ligtit grey, dense, wet Atterberg Total Depth: 25-1/2 feet Groundwater: 20 feet Backfilled: 11/6/01 Clayey sand (SC), light grey, dense, wet Gradation PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-10 LOG OF EXPLORATION BORING NO. 11 Logged by: MA Date Drilled: 11/6/01 Method of Drilling: 8-inch diameter hollow-stem auger Elevation: +/- 43' MSL oc til a. CO I _i oo o a. CO z UJ Q UJ CC 3 I- co O E DESCRIPTION LAB TESTS - 1 2 - 3 - 4 5 f- 6 7 - 8 - 9 - 10 - 11 - 12 - 13 14 15 - 16 - 17 - 18 19 20 21 22 23 24 25 SPT 21 SPT 15 SPT 21 SPT 27 SPT 80+ RESIDUAL SOIL: Silty sand (SM), brown, fine to medium, dense trace gravel, moist medium dense Gradation BAY POINT FORMATION: Silty sand (SM), yellow-brown to orange, fine to medium, medium dense, trace gravel, moist Well graded sand (SW), fine to coarse, trace gravel, medium dense, moist Gobbles at 17 feet SANTIAGO FORMATION: Clayey sandstone (SC), light grey, very dense, moist to wet, trace gravel and caliche Total Depth: 21-1/2 feet No Groundwater Backfilled: 11/6/01 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-11 LOG OF EXPLORATION BORING NO. 12 Logged by: MA Date Drilled: 11/6/01 Method of Drilling: 8-inch diameter hollow-stem auger Elevation: +/- 43* MSL P IL X H 0. UJ cc til a. in I _i ffi CO z UJ Q UJ cc 3 1-co O S DESCRIPTION LAB TESTS 1 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 10 11 h 12 13 14 - 15 - 16 17 18 - 19 - 20 - 21 - 22 - 23 - 24 - 25 SPT 57 SPT 28 SPT 20 SPT 39 SPT 69 RESIDUAL SOIL: Silty sand (SM), brown, fine to medium, dense trace clay, weak cementation, dry medium dense, dry to moist Sulfate pH Resistivity Chloride BAY POINT FORMATION: Poorly graded sand (SP), yellow-brown to orange. fine to medium, medium dense, moist Well graded sand (SW), fine to coarse, trace gravel and caliche, medium dense, moist Cobbles at 17 feet SANTIAGO FORMATION: Clayey sandstone (SC), light grey, very dense. moist to wet, trace gravel and caliche Total Depth: 21-1/2 feet No Groundwater Backfilled: 11/6/01 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-12 Logged by: MA Method of Drilling: LOG OF EXPLORATION BORING NO. 13 Date Drilled: 11/6/01 8-inch diameter hollow-stem auger Elevation: +/- 43' MSL DEPTH (FT) BLOWS PER FT DRIVE SAMPLE BULK SAMPLE DENSITY (PCF) MOISTURE (%) DESCRIPTION LAB TESTS - 1 - 2 _ "J SPT RESIDUAL SOIL: Siltv sand fSMV brown fine tn mfirlinm rionco o - 4 19 trace clay, weak cementation, dry - 5 - 6 16 'm' medium dense, dry to moist - 7 - 8 - 9 - 10 - 11 SPT BAY POINT FORMATION: Pooriv arader) sand (RP\ ypllnw-hrnwn tn nrango - 11 18 fine to medium, medium dense, moist - 12 - 13 - 14 - 15 - 16 27 SPT Well graded sand (SW), fine to coarse, trace gravel and caliche, medium dense, moist - 17 - 18 - 19 - 20 - 21 - 22 - 23 - 24 - 25 PROJECT NO. 0703-001-00 GEOTECHNICS INCORPORATED FIGURE B-13 APPENDIX C LABORATORY TESTING Selected samples of soils encountered during the investigation were tested using generally accepted testing standards. The soils selected for testing are believed to be generally representative of the materials encountered during the investigation at the site; however, variations may occur in the soils at the site, and the materials tested may not be representative of the materials encountered during construction. A brief description of the tests performed follows: Laboratory testing was conducted in a marmer consistent with that level of care and skill ordinarily exercised by members of the profession currently practicing under similar conditions and in the same locality. No other warranty, expressed or implied, is made as to the correctness or serviceability of the test results or the conclusions derived from these tests. Where a specific laboratory test method has been referenced, such as ASTM, Caltrans, or AASHTO, the reference applies only to the specified laboratory test method and not to associated referenced test method(s) or practices, and the test method referenced has been used only as a guidance document for the general performance of the test and not as a "Test Standard." Classification: Soils were classified visually according to the Unified Soil Classification System as established by the American Society of Civil Engineers. The resultant soil classifications are shown on the boring logs in Appendix B. Sulfate Content: To assess the potential for reactivity with below grade concrete, selected soil samples were tested for water-soluble sulfate content. The water-soluble sulfate was extracted under vacuum from the soil using a 10:1 (water to dry soil) dilution ratio. The extracted solution was then tested for water-soluble sulfate in general accordance with ASTM test method D 516. The results are presented on Figure C-1. pH and Resistivity: To assess the potential for reactivity with buried metal pipe and below grade ferrous materials, selected soil samples were tested for pH and resistivity in general accordance with the laboratory procedures outlined in Caltrans test method 643. The results are shovra on Figure C-1. Chloride Content: Selected soil samples were evaluated for chloride content in general accordance with the Standard Method for Evaluation of Waste Water Test SMEWW4500CL-C, which is conducted in general conformance with EPA Test Method 375.4. The results are presented on Figure C-1. Maximum Density/Optimum Moisture: The maximum dry density and optimum moisture content of a selected soil sample was estimated in general accordance with the laboratory procedures outlined in ASTM test method D 1557, modified Proctor. The test results are summarized in Figure C-2. Geotechnics Incorporated APPENDIX C LABORATORY TESTING (continued) Atterberg Limits; The liquid limit, plastic limit, and plasticity index of a selected fine-grained soil samples was estimated in general accordance with the laboratory procedures outlined in ASTM test method D 4318. The results are given in Figures C-2. Expansion Index: The expansion potential of a selected soil sample was characterized by using ASTM test method D 4829 as a guideline. Figure C-2 provides a summary of the test results. R-Value: To assess the potential strength of the on-site soils as pavement subgrade materials, R- Value testing was performed on a selected bulk sample of the near-surface materials in general accordance with ASTM test method D 2844. The results are presented in Figure C-2. Particle Size Analvsis: Particle size analyses were performed in general accordance with the laboratory procedures outlined in ASTM test method D 422. The results are summarized in Figures C-3, C-4, C-5, and C-6. Consolidation: A selected, relatively undisturbed soil sample was evaluated for one-dimensional consolidation properties in general accordance with ASTM test method D 2435. The test results are summarized in Figures C-7. Direct Shear: The shear strength of a selected soil sample was assessed through direct shear testing performed in general accordance with the laboratory procedures outlined in ASTM test method D 3080. The results are summarized in Figure C-8. Geotechnics Incorporated pH, RESISTIVITY, SULFATE, AND CHLORIDE SAMPLE WATER-SOLUBLE SULFATE CONTENT (% of Dry Soil Weight) (ASTM D 516) pH (CALTRANS 643) RESISTIVITY (ohm-cm) (CALTRANS 643) WATER-SOLUBLE CHLORIDE CONTENT (% of Dry Soil Weight) (SMEWW4500CLC) B-3 @ 2' - 3' 0.009 8.4 1256 Not Tested B-W@ r-4' 0.002 8.5 2860 0.0034 B-12 @ 5' 0.01 9.1 2511 0.0048 Soil Resistivity in ohm-cm General Degree of Corrosivity to Ferrous Metal 0 to 1,000 Very Corrosive 1,000 to 2,000 Corrosive 2,000 to 5,000 Moderately Corrosive 5,000 to 10,000 Mildly Corrosive Greaterthan 10,000 Slightly Corrosive Water Soluble Chloride (Cl) Content in % of Dry Soil Weight General Degree of Corrosivity to Metal over 0.15 % Severely Corrosive 0.15% to 0.03% Corrosive 0.03 % to 0.00 % Negligible Water Soluble Sulfate (SOJ Content in % of Dry Soil Weight General Degree of Reactivity with Concrete over 2.00 % Very Severely Reactive 2.00 % to 0.2 % Severely Reactive 0.20% to 0.10% Moderately Reactive 0.10% to 0.00% Negligible Reference Table 19-A-4, 1997 Uniform Building Code Geotechnics Incorporated LABORATORY TEST RESULTS ProjectNo. 0703-001-00 Document No. 1-1248 FIGURE C-1 MAXIMUM DENSITY/OPTIMUM MOISTURE CONTENT (ASTM D1557) SAMPLE DESCRIPTION MAXIMUM DENSITY (pcf) OPTIMUM MOISTURE (%) B-5 @ r-4' Yellow-Brown silty SAND (SM) 133 7-1/2 ATTERBERG LIMITS (ASTM D 4318) SAMPLE LIQUID LIMIT (%) PLASTIC LIMIT (%) PLASTICITY INDEX (%) SOIL CLASSIFICATION B-10 (g 20' 43 22 21 CL R-VALUE (ASTM D2844) SAMPLE DESCRIPTION R-VALUE B-4 @ 0' - 3' Red-Brown clayey SAND (SC) 61 EXPANSION INDEX (ASTM D4829) SAMPLE DESCRIPTION EXPANSION INDEX B-4 @ 1'-3' Orange-Brown clayey SAND (SC) 17 UBC TABLE 18-I-B, CLASSIFICATION OF EXPANSIVE SOIL EXPANSION INDEX POTENTIAL EXPANSION 0-20 Very Low 21-50 Low 51-90 Medium 91-130 High Above 130 Very High Geotechnics Incorporated LABORATORY TEST RESULTS Project No. 0703-001-00 Document No. 1-1248 FIGURE C-2 '5 >» .a V c c o o 0) 0. 1-1/2" 3/4" 3/8" #4 U.S. Standard Sieve #8 #16 #30 #50 #100 #200 Hydrometer 0.01 0.001 Grain Size in Millimeters COARSE FINE COARSE MEDIUM FINE SILT AND CLAY GRAVEL SAND SILT AND CLAY SAMPLE UNIFIED SOIL CLASSIFICATION: SP DESCRIPTION: BAY POINT FORMATION: Sand (SP) with silt ATTERBERG LIMITS EXPLORATION NUMBER: B-1 SAMPLE DEPTH: 10' UNIFIED SOIL CLASSIFICATION: SP DESCRIPTION: BAY POINT FORMATION: Sand (SP) with silt UQUID LIMIT PLASTIC LIMIT PLASTICITY INDEX UQUID LIMIT PLASTIC LIMIT PLASTICITY INDEX ^^^^^ G eotechnics Project No. 0703-001-00 i^HI^B^^^n corp or ated SOIL CLASSIFICATION Document NO. 1-1248 FIGURE C-3 rev. 3-98 3" 1-1/2" 3/4" 3/8" #4 U.S. Standard Sieve #8 #16 #30 #50 #100 #200 100 90 80 70 60 50 40 30 20 10 0 Hydrometer « >. .o I— o c c « a. 100 10 0.1 0.01 0.001 Grain Size in Millimeters COARSE FINE COARSE MEDIUM FINE SILT AND CLAY GRAVEL SAND SILT AND CLAY SAMPLE EXPLORATION NUMBER: B-4 SAMPLE DEPTH: 10' UNIFIED SOIL CLASSIFICATION: SP DESCRIPTION: BAY POINT FORMATION: Sand (SP) with silt ATTERBERG UMITS LIQUID LIMIT PLASTIC LIMIT PLASTICITY INDEX Geotechnics Incorporated SOIL CLASSIFICATION Project NO. 0703-001-00 Document No. 1-1248 FIGURE C-4 rev. 3-98 3" 1-1/2" 3/4" 3/8" #4 U.S. Standard Sieve #8 #16 #30 #50 #100 #200 Hydrometer 0.01 0.001 Grain Size in Millimeters COARSE FINE COARSE MEDIUM FINE SILT AND CLAY GRAVEL SAND SILT AND CLAY SAMPLE EXPLORATION NUMBER: B-10 SAMPLE DEPTH: 25' UNIFIED SOIL CLASSIFICATION: DESCRIPTION: Clayey Sand SC ATTERBERG LIMITS UQUID UMIT PLASTIC LIMIT PLASTICITY INDEX Geotechnics Incorporated SOIL CLASSIFICATION Project No. 0703-001-00 Document No. 1-1248 FIGURE C-5 rev. 3-98 100 90 80 70 - 60 .c O) °5 5 50 >. n 1-1/2" 3/4" 3/8" #4 U.S. Standard Sieve #8 #16 #30 #50 #100 #200 Hydrometer c 40 S 30 0) CL 20 10 0 100 10 0.1 0.01 0.001 Grain Size in Millimeters COARSE FINE COARSE MEDIUM FINE SILT AND CLAY GRAVEL SAND SILT AND CLAY SAMPLE EXPLORATION NUMBER: B-11 SAMPLE DEPTH: 5' UNIFIED SOIL CLASSIFICATION: DESCRIPTION: Silty Sand SM ATTERBERG UMITS UQUID LIMIT PLASTIC LIMIT PLASTICITY INDEX Geotechnics Incorporated SOIL CLASSIFICATION ProjectNo. 0703-001-00 Document No. 1-1248 FIGURE C-6 rev. 3-98 0.00% 1.00% 2.00% c s Ui c » u V 3.00% 4.00% 5.00% 10.0 100.0 1000.0 10000.0 B2@ 5' INITIAL FINAL 1.0000 0.9757 116.6 119.5 2.70 2.70 0.45 0.41 11.0 13.9 66.7 91.6 Stress [psf] Water added to sample after consolidation under a load of 1,973 psf. SAMPLE HEIGHT [IN] DRY DENSITY [PCF] SPECIFIC GRAVITY VOID RATIO WATER CONTENT [%] DEGREE OF SATURATION [%] Geotechnics Incorporated Consolidation Test Results Laguna Point Condominiums Wave Crest Resorts II Project No. 0703-001-00 Document No. 1-1284 FIGURE C-7 8.0 10.0 12.0 STRAIN [%] 14.0 16.0 18.0 20.0 u. (0 Q. (O V) Ul H Ui < Ul X Ui 5000 4500 4000 3500 3000 2500 2000 1500 1000 500 0 - - • ULTIMATE SHEAR: BPEAK SHEAR: - • • -1 - < -I 1 ! i - A > 1 1 1 , 1 1 1 —1—\ 1 1 1 1 1 , 1 i 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 NORMAL STRESS [PSF] SAMPLE: B3@5' PEAK ULTIMATE BAY POINT FORMAITON: Sand (SP) *• 47° 40 ° C 0 PSF 0 PSF IN-SITU AS-TESTED STRAIN RATE: 0.0100 IN/MIN Yd 120.5 PCF 120.5 PCF (Sample was consolidated and drained) Wc 10.7 % 16.8 % Geotechnics Incorporated DIRECT SHEAR TEST RESULTS Laguna Point Condominiums Wave Crest Resorts II Project No. 0703-001-00 Document No. 1-1248 FIGURE C-8