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HomeMy WebLinkAboutParcel Map 19607 Parcel 3 Soils Report - Hall ResidenceEARTH STRATA GEOTECHNICAL SERVICES Page i March 4, 2022 Project No. 214152-10A TABLE OF CONTENTS Section Page INTRODUCTION ....................................................................................................................................................1 SITE DESCRIPTION ...............................................................................................................................................1 PROPOSED DEVELOPMENT AND GRADING .................................................................................................1 FIELD EXPLORATION AND LABORATORY TESTING ......................................................................................3 Field Exploration ..............................................................................................................................................3 Laboratory Testing ..........................................................................................................................................3 FINDINGS ................................................................................................................................................................3 Regional Geology ..............................................................................................................................................3 Local Geology ....................................................................................................................................................4 Faulting ..............................................................................................................................................................6 Landslides ..........................................................................................................................................................6 CONCLUSIONS AND RECOMMENDATIONS .......................................................................................................6 General ...............................................................................................................................................................6 Earthwork ..........................................................................................................................................................7 Earthwork and Grading ..............................................................................................................................7 Clearing and Grubbing ................................................................................................................................7 Excavation Characteristics .........................................................................................................................7 Groundwater .................................................................................................................................................7 Ground Preparation for Fill Areas ............................................................................................................7 Oversize Rock ...............................................................................................................................................8 Compacted Fill Placement ..........................................................................................................................8 Import Earth Materials ...............................................................................................................................8 Cut/Fill Transitions .....................................................................................................................................9 Cut Areas ......................................................................................................................................................10 Shrinkage, Bulking and Subsidence .......................................................................................................10 Geotechnical Observations ......................................................................................................................10 Post Grading Considerations .......................................................................................................................10 Slope Landscaping and Maintenance .....................................................................................................10 Site Drainage ...............................................................................................................................................11 Utility Trenches ..........................................................................................................................................11 SEISMIC DESIGN CONSIDERATIONS ................................................................................................................11 Ground Motions ..............................................................................................................................................11 Secondary Seismic Hazards .........................................................................................................................12 Liquefaction and Lateral Spreading ...........................................................................................................13 General .............................................................................................................................................................13 Allowable Bearing Values .............................................................................................................................13 Settlement........................................................................................................................................................13 Lateral Resistance ..........................................................................................................................................14 Structural Setbacks and Building Clearance ............................................................................................14 Foundation Observations .............................................................................................................................15 Expansive Soil Considerations ....................................................................................................................16 Very Low Expansion Potential (Expansion Index of 20 or Less) ......................................................16 Footings. .......................................................................................................................................................16 Building Floor Slabs ...................................................................................................................................16 EARTH STRATA GEOTECHNICAL SERVICES Page ii March 4, 2022 Project No. 214152-10A RETAINING WALLS .............................................................................................................................................18 Active and At-Rest Earth Pressures ............................................................................................................18 Subdrain System .............................................................................................................................................18 Temporary Excavations ................................................................................................................................19 Retaining Wall Backfill .................................................................................................................................19 CONCRETE FLATWORK .....................................................................................................................................19 Thickness and Joint Spacing ........................................................................................................................19 Subgrade Preparation ...................................................................................................................................19 SLOPE STABILITY ...............................................................................................................................................20 Deep Seated Stability .....................................................................................................................................20 Surficial Stability ............................................................................................................................................20 Slope Stability Results ...................................................................................................................................21 GRADING PLAN REVIEW AND CONSTRUCTION SERVICES .........................................................................21 REPORT LIMITATIONS ......................................................................................................................................22 Attachments: Figure 1 – Vicinity Map (Page 2) Figure 2 – Regional Geologic Map (Page 5) APPENDIX A – References (Rear of Text) APPENDIX B – Exploratory Logs (Rear of Text) APPENDIX C – Laboratory Procedures and Test Results (Rear of Text) APPENDIX D – Seismicity (Rear of Text). APPENDIX E – Slope Stability Analysis (Rear of Text). APPENDIX F – General Earthwork and Grading Specifications (Rear of Text) Plate 1 – Geotechnical Map (Rear of Text) EARTH STRATA GEOTECHNICAL SERVICES 1 March 4, 2022 Project Number 214152-10A INTRODUCTION Earth Strata Geotechnical Services is pleased to present our preliminary geotechnical interpretive report for the proposed development. The purpose of this study was to evaluate the nature, distribution, engineering properties, and geologic strata underlying the site with respect to the proposed development, and then provide preliminary grading and foundation design recommendations based on the plans you provided. The general location of the subject property is indicated on the Vicinity Map, Figure 1. The plans you provided were used as the base map to show geologic conditions within the subject site, see Geotechnical Map, Plate 1. SITE DESCRIPTION The subject property is located north of Lolita Road in the City of Temecula, Riverside County, California. The approximate location of the site is shown on the Vicinity Map, Figure 1. The subject property is comprised of an undeveloped parcel of land. Topographic relief at the subject property is relatively moderate with the terrain being generally sloping. Elevations at the site range from approximately 1184 to 1250 feet above mean sea level (msl), for a difference of about 66± feet across the entire site. Drainage within the subject property generally flows to the south. The site is currently bordered by residential development to the north, east, and west as well as Lolita Road to the south. Most of the vegetation on the site consists of moderate amounts of annual weeds/grasses, along with native vegetation in the northwestern portion of the subject site. PROPOSED DEVELOPMENT AND GRADING The proposed residential development is expected to consist of a concrete, wood or steel framed one- and/or two-story structure utilizing slab on grade construction with associated drives, landscape areas, and utilities. The current development plans include one (1) building positioned on the site. The plans provided by you were utilized in our exploration and form the base for our Geotechnical Map, Plate 1. Current plans call for 1.5:1 (h:v) cut slopes up to 27 feet high and 1.5:1 (h:v) fill slopes up to 17 feet high. N PROPOSED SINGLE FAMILY RESIDENCE 214152-10A VICINITY MAP FEB 2022 FIGURE 1 SEE BAR SCALE Geotechnical, Environmental and Materials Testing Consultants www.ESGSINC.com (951) 397-8315 Earth Strata Geotechnical Services, Inc. 214152-10A APPROXIMATE SITE LOCATION EARTH STRATA GEOTECHNICAL SERVICES 3 March 4, 2022 Project Number 214152-10A FIELD EXPLORATION AND LABORATORY TESTING Field Exploration Subsurface exploration within the subject site was performed on February 7, 2022 for the exploratory excavations. A hand auger was utilized to excavate three (3) borings to a maximum depth of 5 feet. An underground utilities clearance was obtained from Underground Service Alert of Southern California, prior to the subsurface exploration. Earth materials encountered during exploration were classified and logged in general accordance with the Standard Practice for Description and Identification of Soils (Visual-Manual Procedure) of ASTM D 2488. Upon completion of laboratory testing, exploratory logs and sample descriptions may have been reconciled to reflect laboratory test results with regard to ASTM D 2487. Associated with the subsurface exploration was the collection of bulk (disturbed) samples and relatively undisturbed samples of earth materials for laboratory testing and analysis. The relatively undisturbed samples were obtained with a 3 inch outside diameter modified California split-spoon sampler lined with 1-inch-high brass rings. The central portions of the driven samples were placed in sealed containers and transported to our laboratory for testing and analysis. The approximate exploratory locations are shown on Plate 1 and descriptive logs are presented in Appendix B. Laboratory Testing Maximum dry density/optimum moisture content, expansion potential, pH, resistivity, sulfate content, chloride content, and in-situ density/moisture content were determined for selected undisturbed and bulk samples of earth materials, considered representative of those encountered. An evaluation of the test data is reflected throughout the Conclusions and Recommendations section of this report. A brief description of laboratory test criteria and summaries of test data are presented in Appendix C. FINDINGS Regional Geology Regionally, the site is located in the Peninsular Ranges Geomorphic Province of California. The Peninsular Ranges are characterized by northwest trending steep mountain ranges separated by sediment filled elongated valleys. The dominant structural geologic features reflect the northwest trend of the province. Associated with and subparallel to the San Andreas Fault are the San Jacinto Fault, Newport-Inglewood, and the Whittier-Elsinore Fault. The Santa Ana Mountains abut the west side of the Elsinore Fault while the Perris Block forms the other side of the fault zone to the east. The Perris Block is bounded to the east by the San Jacinto Fault. The northern perimeter of the Los Angeles basin forms part of a northerly dipping blind thrust fault at the boundary between the Peninsular Ranges Province and the Transverse Range Province. The mountainous regions within the Peninsular Ranges Province are comprised of Pre-Cretaceous, metasedimentary, and metavolcanic rocks along with Cretaceous plutonic rocks of the Southern California Batholith. The low lying areas are primarily comprised of Tertiary and Quaternary non-marine alluvial sediments consisting of alluvial deposits, sandstones, claystones, siltstones, conglomerates, and occasional EARTH STRATA GEOTECHNICAL SERVICES 4 March 4, 2022 Project Number 214152-10A volcanic units. A map illustrating the regional geology is presented on the Regional Geologic Map, Figure 2. Local Geology The earth materials on the site are primarily comprised of topsoil and sedimentary bedrock. A general description of the dominant earth materials observed on the site is provided below: · Topsoil (no map symbol): Residual topsoil, encountered in the upper foot, blankets the site and underlying Pauba Formation. These materials were noted to be generally light brown to grayish brown, silty sand which were in a moist and loose state. · Quaternary Pauba Formation (map symbol Qps): Pauba Formation bedrock was generally encountered below the topsoil to the full depth of our exploration. These materials primarily consisted of grayish brown, reddish brown, and light gray fine to coarse grained sandstone with varying amounts of silt and clay. These materials were generally noted to be in a slightly moist to moist and soft to moderately hard state. Typically, the upper 1 to 3 feet of this unit is slightly more weathered and breaks down to silty or clayey sands. N REFERNCES: Kennedy, M.P., Tan, S.S., Bovard, K.R., Alvarez, R.M., Watson, M.J., and Gutierrez, C.I., 2007, Geologic map of the Oceanside 30x60-minute quadrangle, California, California Geological Survey, Regional Geologic Map No. 2, 1:100,000. PROPOSED SINGLE FAMILY RESIDENCE 214152-10A REGIONAL GEOLOGIC MAP FEB 2022 FIGURE 2 SCALE 1:36,112 LEGEND Qps - Quaternary Pauba Formation Geotechnical, Environmental and Materials Testing Consultants www.ESGSINC.com (951) 397-8315 Earth Strata Geotechnical Services, Inc. 214152-10A - APPROXIMATE SITE LOCATION EARTH STRATA GEOTECHNICAL SERVICES 6 March 4, 2022 Project Number 214152-10A Faulting The project is located in a seismically active region and as a result, significant ground shaking will likely impact the site within the design life of the proposed project. The geologic structure of the entire southern California area is dominated by northwest-trending faults associated with the San Andreas Fault system, which accommodates for most of the right lateral movement associated with the relative motion between the Pacific and North American tectonic plates. Known active faults within this system include the Newport-Inglewood, Whittier-Elsinore, San Jacinto and San Andreas Faults. No active faults are known to project through the site and the site is not located within an Alquist-Priolo Earthquake Fault Zone, established by the State of California to restrict the construction of new habitable structures across identifiable traces of known active faults. An active fault is defined by the State of California as having surface displacement within the past 11,000 years or during the Holocene geologic time period. Based on our mapping of the subject site, review of current and historical aerial imagery, lack of lineaments indicative of active faulting, and the data compiled during the preparation of this report, it is our interpretation that the potential for surface rupture to adversely impact the proposed structures is very low to remote. Based on our review of regional geologic maps and applicable computer programs (USGS Seismic Design Maps, Caltrans ARS online, and USGS Earthquake Hazard Programs), the Elsinore Fault with an approximate source to site distance of 5.79 kilometers is the closest known active fault anticipated to produce the highest ground accelerations, with an anticipated maximum modal magnitude of 7.7. A list of faults as well as a list of significant historical seismic events within a 100km radius of the subject site are included in Appendix D. Landslides Landslide debris was not observed during our subsurface exploration and no ancient landslides are known to exist on the site. No landslides are known to exist, or have been mapped, in the vicinity of the site. Geologic mapping of the site conducted during our investigation, and review of aerial imagery of the site, reveal no geomorphic expressions indicative of landsliding. CONCLUSIONS AND RECOMMENDATIONS General From geotechnical and engineering geologic points of view, the subject property is considered suitable for the proposed development, provided the following conclusions and recommendations are incorporated into the plans and are implemented during construction. EARTH STRATA GEOTECHNICAL SERVICES 7 March 4, 2022 Project Number 214152-10A Earthwork Earthwork and Grading The provisions of the 2019 California Building Code (CBC), including the General Earthwork and Grading Specifications in the last Appendix of this report, should be applied to all earthwork and grading operations, as well as in accordance with all applicable grading codes and requirements of the appropriate reviewing agency. Unless specifically revised or amended herein, grading operations should also be performed in accordance with applicable provisions of our General Earthwork and Grading Specifications within the last appendix of this report. Clearing and Grubbing Vegetation including trees, grasses, weeds, brush, shrubs, or any other debris should be stripped from the areas to be graded and properly disposed of offsite. In addition, laborers should be utilized to remove any roots, branches, or other deleterious materials during grading operations. Earth Strata Geotechnical Services should be notified at the appropriate times to provide observation and testing services during Clearing and Grubbing operations. Any buried structures or unanticipated conditions should be brought to our immediate attention. Excavation Characteristics Based on the results of our exploration and experience with similar projects in similar settings, the near surface earth materials, will be readily excavated with conventional earth moving equipment. Groundwater Groundwater was not observed during our subsurface exploration. Local well data indicates groundwater at depths greater than 100 feet below ground surface. It should be noted that localized groundwater could be encountered during grading due to the limited number of exploratory locations or other factors. Ground Preparation for Fill Areas For each area to receive compacted fill, the removal of low density, compressible earth materials, such as topsoil and upper alluvial materials should continue until firm competent sedimentary bedrock is encountered. Removal excavations are subject to verification by the project engineer, geologist or their representative. Prior to placing compacted fills, the exposed bottom in each removal area should be scarified to a depth of 6 inches or more, watered or air dried as necessary to achieve near optimum moisture conditions and then compacted to a minimum of 90 percent of the maximum dry density determined by ASTM D 1557. The intent of remedial grading is to diminish the potential for hydro-consolidation, slope instability, and/or settlement. Remedial grading should extend beyond the perimeter of the proposed structures a horizontal distance equal to the depth of excavation or a minimum of 5 feet, whichever is greater. For cursory purposes the anticipated removal depths are shown on the enclosed EARTH STRATA GEOTECHNICAL SERVICES 8 March 4, 2022 Project Number 214152-10A Geotechnical Map, Plate 1. In general, the anticipated removal depths should vary from 5 to 7 feet below existing grade. Wet Removals Wet alluvial materials will probably not be encountered within the low lying areas of the site. If removals of wet alluvial materials are required, special grading equipment and procedures can greatly reduce overall costs. Careful planning by an experienced grading contractor can reduce the need for special equipment, such as swamp cats, draglines, excavators, pumps, and top loading earthmovers. Possible solutions may include the placement of imported angular rock and/or geotextile ground reinforcement. More specific recommendations can be provided based on the actual conditions encountered. Drying or mixing of wet materials with dry materials will be needed to bring the wet materials to near optimum moisture prior to placing wet materials into compacted fills. Oversize Rock Oversize rock is not expected to be encountered during grading. Oversize rock that is encountered (i.e., rock exceeding a maximum dimension of 12 inches) should be disposed of offsite or stockpiled onsite and crushed for future use. The disposal of oversize rock is discussed in greater detail in General Earthwork and Grading Specifications within the last appendix of this report. Compacted Fill Placement Compacted fill materials should be placed in 6 to 8 inch maximum (uncompacted) lifts, watered or air dried as necessary to achieve uniform near optimum moisture content and then compacted to a minimum of 90 percent of the maximum dry density determined by ASTM D 1557. Import Earth Materials Should import earth materials be needed to achieve final design grades, all potential import materials should be free of deleterious/oversize materials, non-expansive, and approved by the project geotechnical consultant prior to delivery onsite. Fill Slopes Current plans call for fill slopes up to 17 feet high with inclinations of 1.5:1 (h:v). Keyways are required at the toe of all fill slopes higher than 5 feet and steeper than 5:1 (h:v). Keyways should be a minimum of 10 feet wide and 2 feet into competent earth materials, as measured on the downhill side. In order to establish keyway removals, backcuts should be cut no steeper than 1:1 or as recommended by the geotechnical engineer or engineering geologist. Compacted fill should be benched into competent earth materials. EARTH STRATA GEOTECHNICAL SERVICES 9 March 4, 2022 Project Number 214152-10A Cut Slopes Current plans call for cut slopes into sedimentary bedrock up to 27 feet high with inclinations of 1.5:1 (h:v). Due to the variability of the sedimentary bedrock, cut slopes in this unit may need to be replaced with a stabilization fill. Cut slopes should be observed by the engineering geologist or his representative during grading, but are anticipated to be stable. Stabilization Fills Stabilization fills may be required for cut slopes in the sedimentary bedrock, pending the results our slope stability analysis. Our engineering geologist or his representative should be called to evaluate all slopes during grading. In the event that unfavorable geologic conditions are encountered, recommendations for stabilization fills or flatter slopes may be provided. Fill Over Cut Slopes The fill portion of fill over cut slopes should not be constructed until the cut portion of the slope has been cut to finish grade. The earth materials and geologic structure exposed along the cut slope should be evaluated with regard to suitability for compacted fills or foundations and for stability. If the cut materials are determined to be competent, then the construction of the keyway and subdrain system may commence or additional remedial recommendations will be provided. Cut/Fill Transitions Cut/fill transitions should be eliminated from all building areas where the depth of fill placed within the “fill” portion exceeds proposed footing depths. This is to diminish distress to structures resulting from excessive differential settlement. The entire foundation of each structure should be founded on a uniform bearing material. This should be accomplished by overexcavating the “cut” portion and replacing the excavated materials as properly compacted fill. Refer to the following table for recommended depths of overexcavation. DEPTH OF FILL (“fill” portion) DEPTH OF OVEREXCAVATION (“cut” portion) Up to 5 feet Equal Depth 5 to 10 feet 5 feet Greater than 10 feet One-half the thickness of fill placed on the “fill” portion (10 feet maximum) Overexcavation of the “cut” portion should extend beyond the building perimeter a horizontal distance equal to the depth of overexcavation or a minimum of 5 feet, whichever is greater. EARTH STRATA GEOTECHNICAL SERVICES 10 March 4, 2022 Project Number 214152-10A Cut Areas In cut areas, an area a minimum of 5 feet beyond the footprint of the proposed structures should overexcavated until; competent bottoms are achieved; to a minimum 3 feet below the proposed foundations; or per the Overexcavation Table above; (whichever is greater) and replaced with compacted fill. Final determination of areas that require overexcavation should be determined in the field by a representative of Earth Strata Geotechnical Services. Shrinkage, Bulking and Subsidence Volumetric changes in earth material quantities will occur when poorly consolidated earth materials are replaced with properly compacted fill. Estimates of the percent shrinkage/bulking factors for the various geologic units observed on the subject property are based on in-place densities and on the estimated average percent of relative compaction achieved during grading. GEOLOGIC UNIT SHRINKAGE (%) Alluvium 10 to 15 Bedrock 0 to 5 (Bulking) Subsidence from scarification and recompaction of exposed bottom surfaces is expected to be negligible to approximately 0.01 foot. The estimates of shrinkage/bulking and subsidence are intended as an aid for project engineers in determining earthwork quantities. Since many variables can affect the accuracy of these estimates, they should be used with caution and contingency plans should be in place for balancing the project. Geotechnical Observations Clearing operations, removal of unsuitable materials, and general grading procedures should be observed by the project geotechnical consultant or his representative. No compacted fill should be placed without observations by the geotechnical consultant or his representative to verify the adequacy of the removals. The project geotechnical consultant or his representative should be present to observe grading operations and to check that minimum compaction requirements and proper lift thicknesses are being met, as well as to verify compliance with the other recommendations presented herein. Post Grading Considerations Slope Landscaping and Maintenance Adequate slope and building pad drainage is essential for the long term performance of the subject site. The gross stability of graded slopes should not be adversely affected, provided all drainage provisions are properly constructed and maintained. Engineered slopes should be landscaped with deep rooted, drought tolerant maintenance free plant species, as recommended by the project landscape architect. EARTH STRATA GEOTECHNICAL SERVICES 11 March 4, 2022 Project Number 214152-10A Site Drainage Control of site drainage is important for the performance of the proposed project. Roof gutters are recommended for the proposed structures. Pad and roof drainage should be collected and transferred to driveways, adjacent streets, storm-drain facilities, or other locations approved by the building official in non-erosive drainage devices. Drainage should not be allowed to pond on the pad or against any foundation or retaining wall. Drainage should not be allowed to flow uncontrolled over any descending slope. Planters located within retaining wall backfill should be sealed to prevent moisture intrusion into the backfill. Planters located next to structures should be sealed to the depth of the footings. Drainage control devices require periodic cleaning, testing and maintenance to remain effective. At a minimum, pad drainage should be designed at the minimum gradients required by the CBC. To divert water away from foundations, the ground surface adjacent to foundations should also be graded at the minimum gradients required per the CBC. Utility Trenches All utility trench backfill should be compacted at near optimum moisture to a minimum of 90 percent of the maximum dry density determined by ASTM D 1557. For utility trench backfill within pavement areas the upper 6 inches of subgrade materials should be compacted to 95 percent of the maximum dry density determined by ASTM D 1557. This includes within the street right-of-ways, utility easements, under footings, sidewalks, driveways and building floor slabs, as well as within or adjacent to any slopes. Backfill should be placed in approximately 6 to 8 inch maximum loose lifts and then mechanically compacted with a hydro-hammer, rolling with a sheepsfoot, pneumatic tampers, or similar equipment. The utility trenches should be tested by the project geotechnical engineer or their representative to verify minimum compaction requirements are obtained. In order to minimize the penetration of moisture below building slabs, all utility trenches should be backfilled with compacted fill, lean concrete or concrete slurry where they undercut the perimeter foundation. Utility trenches that are proposed parallel to any building footings (interior and/or exterior trenches), should not be located within a 1:1 (h:v) plane projected downward from the outside bottom edge of the footing. SEISMIC DESIGN CONSIDERATIONS Ground Motions Structures are required to be designed and constructed to resist the effects of seismic ground motions as provided in the 2019 California Building Code Section 1613. The design is dependent on the site class, occupancy category I, II, III, or IV, mapped spectral accelerations for short periods (Ss), and mapped spectral acceleration for a 1-second period (S1). In order for structural design to comply with the 2019 CBC, the USGS “US Seismic Design Maps” online tool was used to compile spectral accelerations for the subject property based on data and maps jointly compiled by the United States Geological Survey (USGS) and the California Geological Survey (CGS). The EARTH STRATA GEOTECHNICAL SERVICES 12 March 4, 2022 Project Number 214152-10A data found in the following table is based on the Maximum Considered Earthquake (MCE) with 5% damped ground motions having a 2% probability of being exceeded in 50 years (2,475 year return period). The seismic design coefficients were determined by a combination of the site class, mapped spectral accelerations, and occupancy category. The following seismic design coefficients should be implemented during design of the proposed structures. Summaries of the Seismic Hazard Deaggregation graphs and test data are presented in Appendix D. 2019 CBC FACTOR (ASCE 7-16) Site Location Latitude: 33.409342˚ (North) Longitude: -117.125631˚(West) Site Class D-default Mapped Spectral Accelerations for short periods, Ss 1.364 g Mapped Spectral Accelerations for 1-Second Period, S1 0.498 g Maximum Considered Earthquake Spectral Response Acceleration for Short Periods, Sms 1.637 g Maximum Considered Earthquake Spectral Response Acceleration for 1-Second Period, Sm1 Null-See Section 11.4.8* Design Spectral Response Acceleration for Short Periods, SDS 1.092 g Design Spectral Response Acceleration for 1-Second Period, SD1 Null-See Section 11.4.8* Seismic Design Category D Importance Factor Based on Occupancy Category II *2019 CBC We performed the probabilistic seismic hazard assessment for the site in accordance with the 2019 CBC, Section 1803.5.11 and 1803.5.12. The probabilistic seismic hazard maps and data files were jointly prepared by the United States Geological Survey (USGS) and the California Geological Survey (CGS) and can be found at the CGS Probabilistic Seismic Hazards Mapping Ground Motion Page. Actual ground shaking intensities at the site may be substantially higher or lower based on complex variables such as the near source directivity effects, depth and consistency of earth materials, topography, geologic structure, direction of fault rupture, and seismic wave reflection, refraction, and attenuation rates. The mean peak ground acceleration was calculated to be 0.727g. Secondary Seismic Hazards Secondary effects of seismic shaking considered as potential hazards include several types of ground failure as well as induced flooding. Different types of ground failure, which could occur as a consequence of severe ground shaking at the site, include landslides, ground lurching, shallow ground rupture, and liquefaction/lateral spreading. The probability of occurrence of each type of ground failure depends on the severity of the earthquake, distance from faults, topography, the state of subsurface earth materials, groundwater conditions, and other factors. Based on our experience, subsurface exploration, and laboratory testing, all of the above secondary effects of seismic activity are considered unlikely. Seismically induced flooding is normally a consequence of a tsunami (seismic sea wave), a seiche (i.e., a wave-like oscillation of surface water in an enclosed basin that may be initiated by a strong earthquake) or failure of a major reservoir or retention system up gradient of the site. Since the site is at an elevation of EARTH STRATA GEOTECHNICAL SERVICES 13 March 4, 2022 Project Number 214152-10A more than 1200 feet above mean sea level and is located more than 20 miles inland from the nearest coastline of the Pacific Ocean, the potential for seismically induced flooding due to a tsunami is considered nonexistent. Since no enclosed bodies of water lie adjacent to or up gradient of the site, the likelihood for induced flooding due to a dam failure or a seiche overcoming the dam’s freeboard is considered nonexistent. Liquefaction and Lateral Spreading Liquefaction occurs as a result of a substantial loss of shear strength or shearing resistance in loose, saturated, cohesionless earth materials subjected to earthquake induced ground shaking. Potential impacts from liquefaction include loss of bearing capacity, liquefaction related settlement, lateral movements, and surface manifestation such as sand boils. Seismically induced settlement occurs when loose sandy soils become denser when subjected to shaking during an earthquake. The three factors determining whether a site is likely to be subject to liquefaction include seismic shaking, type and consistency of earth materials, and groundwater level. The proposed structures will be supported by compacted fill and competent sedimentary bedrock, with no shallow groundwater. As such, the potential for earthquake induced liquefaction and lateral spreading beneath the proposed structures is considered very low to remote due to the recommended compacted fill, relatively low groundwater level, and the dense nature of the deeper onsite earth materials. TENTATIVE FOUNDATION DESIGN RECOMMENDATIONS General Provided grading is performed in accordance with the recommendations of this report, shallow foundations are considered feasible for support of the proposed structures. Tentative foundation recommendations are provided herein and graphic presentations of relevant recommendations may also be included on the enclosed map. Allowable Bearing Values An allowable bearing value of 2,000 pounds per square foot (psf) is recommended for design of 24-inch square pad footings and 12-inch-wide continuous footings founded at a minimum depth of 12 inches below the lowest adjacent final grade. This value may be increased by 20 percent for each additional 1-foot of width and/or depth to a maximum value of 2,500 psf. Recommended allowable bearing values include both dead and frequently applied live loads and may be increased by one third when designing for short duration wind or seismic forces. Settlement Based on the settlement characteristics of the earth materials that underlie the building sites and the anticipated loading, we estimate that the maximum total settlement of the footings will be less than approximately ¾ inch. Differential settlement is expected to be about ½ inch over a horizontal distance of approximately 20 feet, for an angular distortion ratio of 1:480. It is anticipated that the majority of the settlement will occur during construction or shortly after the initial application of loading. EARTH STRATA GEOTECHNICAL SERVICES 14 March 4, 2022 Project Number 214152-10A The above settlement estimates are based on the assumption that the grading and construction are performed in accordance with the recommendations presented in this report and that the project geotechnical consultant will observe or test the earth material conditions in the footing excavations. Lateral Resistance Passive earth pressure of 250 psf per foot of depth to a maximum value of 2,500 psf may be used to establish lateral bearing resistance for footings. For areas covered with hardscape, passive earth pressure may be taken from the surface. For areas without hardscape, the upper 12 inches of the soil profile must be neglected when calculating passive earth pressure. A coefficient of friction of 0.36 times the dead load forces may be used between concrete and the supporting earth materials to determine lateral sliding resistance. The above values may be increased by one-third when designing for short duration wind or seismic forces. When combining passive and friction for lateral resistance, the passive component should be reduced by one third. In no case shall the lateral sliding resistance exceed one-half the dead load for clay, sandy clay, sandy silty clay, silty clay, and clayey silt. The above lateral resistance values are based on footings for an entire structure being placed directly against compacted fill. Structural Setbacks and Building Clearance Structural setbacks are required per the 2019 California Building Code (CBC). Additional structural setbacks are not required due to geologic or geotechnical conditions within the site. Improvements constructed in close proximity to natural or properly engineered and compacted slopes can, over time, be affected by natural processes including gravity forces, weathering, and long term secondary settlement. As a result, the CBC requires that buildings and structures be setback or footings deepened to resist the influence of these processes. For structures that are planned near ascending and descending slopes, the footings should be embedded to satisfy the requirements presented in the CBC, Section 1808.7 as illustrated in the following Foundation Clearances from Slopes diagram. EARTH STRATA GEOTECHNICAL SERVICES 15 March 4, 2022 Project Number 214152-10A FOUNDATION CLEARANCES FROM SLOPES When determining the required clearance from ascending slopes with a retaining wall at the toe, the height of the slope shall be measured from the top of the wall to the top of the slope. Foundation Observations In accordance with the 2019 CBC and prior to the placement of forms, concrete, or steel, all foundation excavations should be observed by the geologist, engineer, or his representative to verify that they have been excavated into competent bearing materials. The excavations should be per the approved plans, moistened, cleaned of all loose materials, trimmed neat, level, and square. Any moisture softened earth materials should be removed prior to steel or concrete placement. Earth materials from foundation excavations should not be placed in slab on grade areas unless the materials are tested for expansion potential and compacted to a minimum of 90 percent of the maximum dry density. EARTH STRATA GEOTECHNICAL SERVICES 16 March 4, 2022 Project Number 214152-10A Expansive Soil Considerations Preliminary laboratory test results indicate onsite earth materials exhibit an expansion potential of VERY LOW as classified in accordance with 2019 CBC Section 1803.5.3 and ASTM D 4829. Additional, testing for expansive soil conditions should be conducted upon completion of rough grading. The following recommendations should be considered the very minimum requirements, for the earth materials tested. It is common practice for the project architect or structural engineer to require additional slab thickness, footing sizes, and/or reinforcement. Very Low Expansion Potential (Expansion Index of 20 or Less) Our laboratory test results indicate that the earth materials onsite exhibit a VERY LOW expansion potential as classified in accordance with 2019 CBC Section 1803.5.3 and ASTM D 4829. Since the onsite earth materials exhibit expansion indices of 20 or less, the design of slab on ground foundations is exempt from the procedures outlined in Section 1808.6.1 or 1808.6.2. Footings ·Exterior continuous footings may be founded at the minimum depths below the lowest adjacent final grade (i.e. 12-inch minimum depth for one-story, 18-inch minimum depth for two-story, and 24-inch minimum depth for three-story construction). Interior continuous footings for one- , two-, and three-story construction may be founded at a minimum depth of 12 inches below the lowest adjacent final grade. All continuous footings should have a minimum width of 12, 15, and 18 inches, for one-, two-, and three-story structures, respectively per Table 1809.7 of the 2019 CBC, and should be reinforced with a minimum of two (2) No. 4 bars, one (1) top and one (1) bottom. ·Exterior pad footings intended to support roof overhangs, such as second story decks, patio covers and similar construction should be a minimum of 24 inches square and founded at a minimum depth of 18 inches below the lowest adjacent final grade. No special reinforcement of the pad footings will be required. Building Floor Slabs ·Building floor slabs should be a minimum of 4 inches thick and reinforced with a minimum of No. 3 bars spaced a maximum of 24 inches on center, each way. All floor slab reinforcement should be supported on concrete chairs or bricks to ensure the desired placement at mid-depth. ·Interior floor slabs, within moisture sensitive areas, should be underlain by a minimum 10-mil thick moisture/vapor barrier to help reduce the upward migration of moisture from the underlying earth materials. The moisture/vapor barrier used should meet the performance standards of an ASTM E 1745 Class A material, and be properly installed in accordance with ACI publication 318. It is the responsibility of the contractor to ensure that the moisture/vapor barriers are free of openings, rips, or punctures prior to placing concrete. As an option for additional moisture reduction, higher strength concrete, such as a minimum 28-day compressive strength of 5,000 pounds per square inch (psi) may be used. Ultimately, the design EARTH STRATA GEOTECHNICAL SERVICES 17 March 4, 2022 Project Number 214152-10A of the moisture/vapor barrier system and recommendations for concrete placement and curing are the purview of the foundation engineer, taking into consideration the project requirements provided by the architect and owner. ·Garage floor slabs should be a minimum of 4 inches thick and should be reinforced in a similar manner as living area floor slabs. Garage floor slabs should be placed separately from adjacent wall footings with a positive separation maintained with ⅜ inch minimum felt expansion joint materials and quartered with weakened plane joints. A 12-inch-wide turn down founded at the same depth as adjacent footings should be provided across garage entrances. The turn down should be reinforced with a minimum of two (2) No. 4 bars, one (1) top and one (1) bottom. ·The subgrade earth materials below all floor slabs should be pre-watered to promote uniform curing of the concrete and minimize the development of shrinkage cracks, prior to placing concrete. The pre-watering should be verified by Earth Strata Geotechnical Services during construction. Corrosivity Corrosion is defined by the National Association of Corrosion Engineers (NACE) as “a deterioration of a substance or its properties because of a reaction with its environment.” From a geotechnical viewpoint, the “substances” are the reinforced concrete foundations or buried metallic elements (not surrounded by concrete) and the “environment” is the prevailing earth materials in contact with them. Many factors can contribute to corrosivity, including the presence of chlorides, sulfates, salts, organic materials, different oxygen levels, poor drainage, different soil types, and moisture content. It is not considered practical or realistic to test for all of the factors which may contribute to corrosivity. The potential for concrete exposure to chlorides is based upon the recognized Caltrans reference standard “Bridge Design Specifications”, under Subsection 8.22.1 of that document, Caltrans has determined that “Corrosive water or soil contains more than 500 parts per million (ppm) of chlorides”. Based on limited preliminary laboratory testing, the onsite earth materials have chloride contents less than 500 ppm. As such, specific requirements resulting from elevated chloride contents are not required. Specific guidelines for concrete mix design are provided in 2019 CBC Section 1904.1 and ACI 318, Section 4.3 Table 4.3.1 when the soluble sulfate content of earth materials exceeds 0.1 percent by weight. Based on limited preliminary laboratory testing, the onsite earth materials are classified in accordance with Table 4.3.1 as having a negligible sulfate exposure condition. Therefore, structural concrete in contact with onsite earth materials should utilize Type I or II. Based on our laboratory testing of resistivity, the onsite earth materials in contact with buried steel should be considered mildly corrosive. Additionally, pH values below 5.6 and above 9.1 are recognized as being corrosive to many common metallic components. The pH values for the earth materials tested were lower than 9.1 and higher than 5.6. The preliminary test results for corrosivity are based on limited samples, and the initiation of grading may blend various earth materials together. This blending or imported material could alter and increase the detrimental properties of the onsite earth materials. Accordingly, additional testing for chlorides and EARTH STRATA GEOTECHNICAL SERVICES 18 March 4, 2022 Project Number 214152-10A sulfates along with testing for pH and resistivity should be performed upon completion of grading. Laboratory test results are presented in Appendix C. RETAINING WALLS Active and At-Rest Earth Pressures Foundations may be designed in accordance with the recommendations provided in the Tentative Foundation Design Recommendation section of this report. The following table provides the minimum recommended equivalent fluid pressures for design of retaining walls a maximum of 8 feet high. The active earth pressure should be used for design of unrestrained retaining walls, which are free to tilt slightly. The at-rest earth pressure should be used for design of retaining walls that are restrained at the top, such as basement walls, curved walls with no joints, or walls restrained at corners. For curved walls, active pressure may be used if tilting is acceptable and construction joints are provided at each angle point and at a minimum of 15 foot intervals along the curved segments. MINIMUM STATIC EQUIVALENT FLUID PRESSURES (pcf) PRESSURE TYPE BACKSLOPE CONDITION LEVEL 2:1 (h:v) Active Earth Pressure 40 60 At-Rest Earth Pressure 63 95 The retaining wall parameters provided do not account for hydrostatic pressure behind the retaining walls. Therefore, the subdrain system is a very important part of the design. All retaining walls should be designed to resist surcharge loads imposed by other nearby walls, structures, or vehicles should be added to the above earth pressures, if the additional loads are being applied within a 1.5:1 (h:v) plane projected up from the heel of the retaining wall footing. As a way of minimizing surcharge loads and the settlement potential of nearby buildings, the footings for the building can be deepened below the 1.5:1 (h:v)plane projected up from the heel of the retaining wall footing. Upon request and under a separate scope of work, more detailed analyses can be performed to address equivalent fluid pressures with regard to stepped retaining walls, actual retaining wall heights, actual backfill inclinations, specific backfill materials, higher retaining walls requiring earthquake design motions, etc. Subdrain System We recommend a perforated pipe and gravel subdrain system be provided behind all proposed retaining walls to prevent the buildup of hydrostatic pressure behind the proposed retaining walls. The perforated pipe should consist of 4-inch minimum diameter Schedule 40 PVC or ABS SDR-35, placed with the perforations facing down. The pipe should be surrounded by 1 cubic foot per foot of ¾- or 1½ inch open graded gravel wrapped in filter fabric. The filter fabric should consist of Mirafi 140N or equivalent to prevent infiltration of fines and subsequent clogging of the subdrain system. EARTH STRATA GEOTECHNICAL SERVICES 19 March 4, 2022 Project Number 214152-10A In lieu of a perforated pipe and gravel subdrain system, weep holes or open vertical masonry joints may be provided in the lowest row of block exposed to the air to prevent the buildup of hydrostatic pressure behind the proposed retaining walls. Weep holes should be a minimum of 3 inches in diameter and provided at intervals at least every 6 feet along the wall. Open vertical masonry joints should be provided at a minimum of 32 inch intervals. A continuous gravel fill, a minimum of 1 cubic foot per foot, should be placed behind the weep holes or open masonry joints. The gravel should be wrapped in filter fabric consisting of Mirafi 140N or equivalent. The retaining walls should be adequately coated on the backfilled side of the walls with a proven waterproofing compound by an experienced professional to inhibit infiltration of moisture through the walls. Temporary Excavations All excavations should be made in accordance with Cal-OSHA requirements. Earth Strata Geotechnical Services is not responsible for job site safety. Retaining Wall Backfill Retaining wall backfill materials should be approved by the geotechnical engineer or his representative prior to placement as compacted fill. Retaining wall backfill should be placed in lifts no greater than 6 to 8 inches, watered or air dried as necessary to achieve near optimum moisture contents. All retaining wall backfill should be compacted to a minimum of 90 percent of the maximum dry density as determined by ASTM D 1557. Retaining wall backfill should be capped with a paved surface drain. CONCRETE FLATWORK Thickness and Joint Spacing Concrete sidewalks and patio type slabs should be at least 3½ inches thick and provided with construction or expansion joints every 6 feet or less, to reduce the potential for excessive cracking. Concrete driveway slabs should be at least 4 inches thick and provided with construction or expansion joints every 10 feet or less. Subgrade Preparation In order to reduce the potential for unsightly cracking, subgrade earth materials underlying concrete flatwork should be compacted at near optimum moisture to a minimum of 90 percent of the maximum dry density determined by ASTM D 1557 and then moistened to optimum or slightly above optimum moisture content. This moisture should extend to a depth of 12 inches below subgrade and be maintained prior to placement of concrete. Pre-watering of the earth materials prior to placing concrete will promote uniform curing of the concrete and minimize the development of shrinkage cracks. The project geotechnical engineer or his representative should verify the density and moisture content of the earth materials and the depth of moisture penetration prior to placing concrete. EARTH STRATA GEOTECHNICAL SERVICES 20 March 4, 2022 Project Number 214152-10A Cracking within concrete flatwork is often a result of factors such as the use of too high a water to cement ratio and/or inadequate steps taken to prevent moisture loss during the curing of the concrete. Concrete distress can be reduced by proper concrete mix design and proper placement and curing of the concrete. Minor cracking within concrete flatwork is normal and should be expected. SLOPE STABILITY Significance of Slope Stability Analyses Limit equilibrium analyses of slope stability only provide a general indication of the relative stability of a slope. The applicability is highly dependent on the ability of its simplified analytical methodology and the chosen generalized assumptions of soil properties and slope geometry, to accurately model complex geologic conditions that exist in the field. However, in spite of the limitations, limit equilibrium slope stability analyses can be used to provide insight into the relative need for and benefit of slope stabilization measures. Deep Seated Stability Deep seated stability of fill slopes with heights greater than 30 feet or cut slopes steeper than 2:1, were evaluated using Slope/W, a computer application of the Morgenstern Price Method of analysis. Based on our current understanding of the project, slopes on the subject property include 1.5:1 (h:v) cut slopes up to 27 feet high and 1.5:1 (h:v) fill slopes up to 17 feet high are proposed. The factor of safety of the slopes was evaluated under both static and pseudostatic loading conditions. Per local code requirements, the minimum acceptable factor of safety was taken as 1.5 for static loading and 1.1 for pseudostatic loading. The pseudostatic analysis includes the effects of static loads combined with horizontal inertial force acting out of slope and through the center of gravity of the potential sliding mass. A minimum dynamic horizontal force equal to 0.24 times gravity was applied. Surficial Stability The surficial stability of near surface earth materials can be calculated using an infinite slope with seepage occurring parallel to the slope face. In the analysis, the vertical depth of saturation is a minimum of 4 feet, and per local code requirements, the minimum acceptable factor of safety for surficial stability is 1.5 for static loading conditions. Our calculations indicate that the proposed 1.5:1 (h:v) compacted fill slopes without Geogrid will require additional secondary stabilization methods such as netting, spray-on binder, wood or plastic lumber, earth anchors, or soil nails for long-term surficial stability. Slopes should be planted and maintained with drought resistant vegetation to assist with surficial erosion and stability. For cut slopes into bedrock, the surficial earth materials are removed when the cut slopes are constructed. Therefore, the parallel seepage model for calculating surficial stability is not applicable for cut slopes, as the surficial materials have been removed. EARTH STRATA GEOTECHNICAL SERVICES 21 March 4, 2022 Project Number 214152-10A Slope Stability Results The slope stability analyses performed for the sections analyzed on this project indicate that the static factors of safety for potential deep seated slip surfaces are above 1.5 for static and 1.1 for dynamic conditions. The slope stability results are presented in the table below and calculation sheets are presented within the appendices of this report. CALCULATED FACTORS OF SAFETY SLOPE TYPE HEIGHT (ft) STATIC PSEUDOSTATIC Cross Section A-A’ Compacted Fill Slope 17 1.732 1.202 Cross Section B-B’ Cut Slope 27 1.818 1.208 Structural fill slopes orientations of 1.5:1 (h:v) require that Geogrid 5XT, or equivalent, be placed every three vertical feet of compacted fill placed extending from the slope face along near-horizontal planes (2% dip into slope) a distance of half the height of the slope from the toe of slope up to three feet below finish grade, or 1-foot minimum below bottom of footings. An Earth Strata Geotechnical Services geologist should evaluate all slopes in the field during grading and construction. If unfavorable geological conditions are observed or encountered, then stabilization fills or flatter slopes may be required. Any stabilization fills should be constructed per the recommendations herein. All fill slope construction should be properly keyed and benched into competent earth materials. GRADING PLAN REVIEW AND CONSTRUCTION SERVICES This report has been prepared for the exclusive use of Bruno Nascimento and their authorized representative. It likely does not contain sufficient information for other parties or other uses. Earth Strata Geotechnical Services should be engaged to review the final design plans and specifications prior to construction. This is to verify that the recommendations contained in this report have been properly incorporated into the project plans and specifications. Should Earth Strata Geotechnical Services not be accorded the opportunity to review the project plans and specifications, we are not responsibility for misinterpretation of our recommendations. We recommend that Earth Strata Geotechnical Services be retained to provide geologic and geotechnical engineering services during grading and foundation excavation phases of the work. In order to allow for design changes in the event that the subsurface conditions differ from those anticipated prior to construction. Earth Strata Geotechnical Services should review any changes in the project and modify and approve in writing the conclusions and recommendations of this report. This report and the drawings contained within are intended for design input purposes only and are not intended to act as construction drawings or specifications. In the event that conditions encountered during grading or construction operations EARTH STRATA GEOTECHNICAL SERVICES 22 March 4, 2022 Project Number 214152-10A appear to be different than those indicated in this report, this office should be notified immediately, as revisions may be required. REPORT LIMITATIONS Our services were performed using the degree of care and skill ordinarily exercised, under similar circumstances, by reputable soils engineers and geologists, practicing at the time and location this report was prepared. No other warranty, expressed or implied, is made as to the conclusions and professional advice included in this report. Earth materials vary in type, strength, and other geotechnical properties between points of observation and exploration. Groundwater and moisture conditions can also vary due to natural processes or the works of man on this or adjacent properties. As a result, we do not and cannot have complete knowledge of the subsurface conditions beneath the subject property. No practical study can completely eliminate uncertainty with regard to the anticipated geotechnical conditions in connection with a subject property. The conclusions and recommendations within this report are based upon the findings at the points of observation and are subject to confirmation by Earth Strata Geotechnical Services based on the conditions revealed during grading and construction. This report was prepared with the understanding that it is the responsibility of the owner or their representative, to ensure that the conclusions and recommendations contained herein are brought to the attention of the other project consultants and are incorporated into the plans and specifications. The owners’ contractor should properly implement the conclusions and recommendations during grading and construction, and notify the owner if they consider any of the recommendations presented herein to be unsafe or unsuitable. APPENDIX A REFERENCES APPENDIX A References California Building Standards Commission, 2019, 2019 California Building Code, California Code of Regulations Title 24, Part 2, Volume 2 of 2, Based on 2018 International Building Code. California Corrosion Guidelines DeLorme, 2004, (www.delorme.com) Topo USA®. Hart, Earl W. and Bryant, William A., 1997, Fault Rupture Hazard Zones in California, CDMG Special Publication 42, revised 2003. Kennedy, M.P., et all, 2005, Geologic Map of the Oceanside 30' x 60' Quadrangle, California, U.S. Geological Survey, Department of Earth Sciences, University of California, Riverside. National Association of Corrosion Engineers, 1984, Corrosion Basics An Introduction, page 191. Per A.B. Chance® Recommendations, 2003 Southern California Earthquake Center (SCEC), 1999, Recommended Procedures for Implementation of DMG Special Publication 117, Guidelines for Analyzing and Mitigating Liquefaction Hazards in California, March. APPENDIX B EXPLORATORY LOGS Project Name: Lolita Road Logged By: HR Type of Rig: Hand Auger Drop (in): 18 Hole Diameter (in): 3 Hole Location: See Geotechnical Map 42184 Remington Avenue, Temecula, CA 92590 Geotechnical Boring Log B-1 Date: February 7, 2022 M o i s t u r e ( % ) C l a s s i f i c a t i o n Sy m b o l 0 Page: 1 of 1 Project Number: 214152-10A Drilling Company: ESGS Drive Weight (lbs): 10 Top of Hole Elevation (ft): See Map D e p t h ( f t ) B l o w C o u n t P e r Fo o t S a m p l e D e p t h D r y D e n s i t y ( p c f ) 2 88.5 7.5 SW 3.5 N/A N/A 5 10 15 20 25 30 MATERIAL DESCRIPTION Well graded sand, slightly moist, moderatey hard, fine grained, light gray to silty SAND Sandstone; light grayish brown, moist, soft, fine to coarse sand, breaks down Quaternary Pauba Formation (Qps) No Groundwater Total Depth 5 feet Project Name: Lolita Road Logged By: HR Type of Rig: Hand Auger Drop (in): 18 Hole Diameter (in): 3 Hole Location: See Geotechnical Map Geotechnical Boring Log B-2 Date: February 7, 2022 Page: 1 of 1 Project Number: 214152-10A Drilling Company: ESGS Drive Weight (lbs): 10 Top of Hole Elevation (ft): See Map D e p t h ( f t ) B l o w C o u n t P e r Fo o t S a m p l e D e p t h D r y D e n s i t y ( p c f ) M o i s t u r e ( % ) C l a s s i f i c a t i o n Sy m b o l 0 0-5 1.5 93.5 10.6 SM Silty SAND, light brown, slightly moist, loose, fine to coarse sand, organics MATERIAL DESCRIPTION Topsoil Quaternary Pauba Formation (Qps) 3 115.5 13.6 Clayey Sandstone; dark brown, moist, moderately hard, 4.5 103.4 12.0 fine to coarse sand with gravel, breaks down to silty SAND with clay5Total Depth 5 feet No Groundwater 10 15 20 25 42184 Remington Avenue, Temecula, CA 92590 30 Project Name: Lolita Road Logged By: HR Type of Rig: Hand Auger Drop (in): 18 Hole Diameter (in): 3 Hole Location: See Geotechnical Map Geotechnical Boring Log B-3 Date: February 7, 2022 Page: 1 of 1 Project Number: 214152-10A Drilling Company: ESGS Drive Weight (lbs): 10 Top of Hole Elevation (ft): See Map D e p t h ( f t ) B l o w C o u n t P e r Fo o t S a m p l e D e p t h D r y D e n s i t y ( p c f ) M o i s t u r e ( % ) C l a s s i f i c a t i o n Sy m b o l MATERIAL DESCRIPTION 0 Topsoil SM Silty SAND, light brown, slightly moist, loose, fine to coarse sand, organics Quaternary Pauba Formation (Qps) fine to coarse sand Sandstone; reddish brown, slightly moist, moderately hard, 5 Total Depth 4 feet No Groundwater 10 15 20 25 42184 Remington Avenue, Temecula, CA 92590 30 APPENDIX C LABORATORY PROCEDURES AND TEST RESULTS APPENDIX C Laboratory Procedures and Test Results Laboratory testing provided quantitative and qualitative data involving the relevant engineering properties of the representative earth materials selected for testing. The representative samples were tested in general accordance with American Society for Testing and Materials (ASTM) procedures and/or California Test Methods (CTM). Soil Classification: Earth materials encountered during exploration were classified and logged in general accordance with the Standard Practice for Description and Identification of Soils (Visual-Manual Procedure) of ASTM D 2488. Upon completion of laboratory testing, exploratory logs and sample descriptions were reconciled to reflect laboratory test results with regard to ASTM D 2487. Maximum Density Tests: The maximum dry density and optimum moisture content of representative samples were determined using the guidelines of ASTM D 1557. The test results are presented in the table below. SAMPLE NUMBER MATERIAL DESCRIPTION MAXIMUM DRY DENSITY (pcf) OPTIMUM MOISTURE CONTENT (%) B-1 @ 0-4 feet Silty SAND 128.5 8.0 Direct Shear: Direct shear tests were performed on representative remolded and/or undisturbed samples using the guidelines of ASTM D 3080. The test results are presented in the table below and/or on the Direct Shear Plots on Sheet(s) S-*1. SAMPLE LOCATION MATERIAL DESCRIPTION FRICTION ANGLE (degrees) APPARENT COHESION (psf) B-1 @ 3.5 feet SAND with Silt 35 166 B-2 @ 0 to 5 feet Silty SAND 38 63 *Remolded to 90 percent of the maximum dry density. Expansion Index: The expansion potential of representative samples was evaluated using the guidelines of ASTM D 4829. The test results are presented in the table below. SAMPLE NUMBER MATERIAL DESCRIPTION EXPANSION INDEX EXPANSION POTENTIAL B-1 @ 0-4 feet Silty SAND 4 Very Low Minimum Resistivity and pH Tests: Minimum resistivity and pH Tests of select samples were performed using the guidelines of CTM 643. The test results are presented in the table below. SAMPLE NUMBER MATERIAL DESCRIPTION pH MINIMUM RESISTIVITY (ohm-cm) B-1 @ 0-4 feet Silty SAND 6.7 2900 Soluble Sulfate: The soluble sulfate content of select samples was determined using the guidelines of CTM 417. The test results are presented in the table below. SAMPLE NUMBER MATERIAL DESCRIPTION SULFATE CONTENT (% by weight) SULFATE EXPOSURE B-1 @ 0-4 feet Silty SAND 0.001 Negligible Chloride Content: Chloride content of select samples was determined using the guidelines of CTM 422. The test results are presented in the table below. SAMPLE NUMBER MATERIAL DESCRIPTION CHLORIDE CONTENT (ppm) B-1 @ 0-4 feet Silty SAND 50 APPENDIX D SEISMICITY 1/12/22, 9:06 AM U.S. Seismic Design Maps https://seismicmaps.org 1/2 Latitude, Longitude: 33.409342, -117.125631 Date 1/12/2022, 9:04:44 AM Design Code Reference Document ASCE7-16 Risk Category II Site Class D - Default (See Section 11.4.3) Type Value Description SS 1.364 MCER ground motion. (for 0.2 second period) S1 0.498 MCER ground motion. (for 1.0s period) SMS 1.637 Site-modified spectral acceleration value SM1 null -See Section 11.4.8 Site-modified spectral acceleration value SDS 1.092 Numeric seismic design value at 0.2 second SA SD1 null -See Section 11.4.8 Numeric seismic design value at 1.0 second SA Type Value Description SDC null -See Section 11.4.8 Seismic design category Fa 1.2 Site amplification factor at 0.2 second Fv null -See Section 11.4.8 Site amplification factor at 1.0 second PGA 0.606 MCEG peak ground acceleration FPGA 1.2 Site amplification factor at PGA PGAM 0.727 Site modified peak ground acceleration TL 8 Long-period transition period in seconds SsRT 1.364 Probabilistic risk-targeted ground motion. (0.2 second) SsUH 1.52 Factored uniform-hazard (2% probability of exceedance in 50 years) spectral acceleration SsD 1.838 Factored deterministic acceleration value. (0.2 second) S1RT 0.498 Probabilistic risk-targeted ground motion. (1.0 second) S1UH 0.551 Factored uniform-hazard (2% probability of exceedance in 50 years) spectral acceleration. S1D 0.718 Factored deterministic acceleration value. (1.0 second) PGAd 0.777 Factored deterministic acceleration value. (Peak Ground Acceleration) CRS 0.898 Mapped value of the risk coefficient at short periods CR1 0.905 Mapped value of the risk coefficient at a period of 1 s 1/12/22, 9:06 AM U.S. Seismic Design Maps https://seismicmaps.org 2/2 DISCLAIMER While the information presented on this website is believed to be correct, SEAOC /OSHPD and its sponsors and contributors assume no responsibility or liability for its accuracy. The material presented in this web application should not be used or relied upon for any specific application without competent examination and verification of its accuracy, suitability and applicability by engineers or other licensed professionals. SEAOC / OSHPD do not intend that the use of this information replace the sound judgment of such competent professionals, having experience and knowledge in the field of practice, nor to substitute for the standard of care required of such professionals in interpreting and applying the results of the seismic data provided by this website. Users of the information from this website assume all liability arising from such use. Use of the output of this website does not imply approval by the governing building code bodies responsible for building code approval and interpretation for the building site described by latitude/longitude location in the search results of this website. 1/12/22, 9:05 AM This is a an example title https://arsonline.dot.ca.gov/output1-6.php 1/2 ARS Online V3.0.2 Using the tool: Specify latitude and longitude in decimal degrees in the input boxes below. Alternatively, Google Maps can be used to find the site location. Specify the time- averaged shear-wave velocity in the upper 30m (Vs30) in the input box. After submitting the data, the USGS 2014 hazard data for a 975-year return period will be reported along with adjustment factors required by Caltrans Seismic Design Criteria (SDC) V2.0. Latitude: 33.409342 Longitude: -117.125631 Vs30 (m/s): 270 Submit Caltrans Design Spectrum (5% damping) Period(s)Sa2008(g)Sa2014(g)Basin2008 Basin2014 Near Fault Amp Design Sa2008(g) Design Sa2014(g) PGA 0.49 0.5 1 1 1 0.49 0.5 0.10 0.85 0.86 1 1 1 0.85 0.86 0.20 1.06 1.15 1 1 1 1.06 1.15 0.30 1.05 1.24 1 1 1 1.05 1.24 0.50 0.93 1.12 1 1 1 0.93 1.12 0.75 0.78 0.88 1 1 1.04 0.81 0.91 1.0 0.64 0.7 1 1 1.07 0.69 0.75 2.0 0.36 0.36 1 1 1.07 0.39 0.38 3.0 0.24 0.23 1 1 1.07 0.26 0.25 4.0 0.17 0.16 1 1 1.07 0.19 0.18 5.0 0.14 0.12 1 1 1.07 0.15 0.13 Copy table Deaggregation (based on 2014 hazard) mean magnitude (for PGA)6.69 mean site-source distance (km, for Sa at 1s)21.4 1/12/22, 9:05 AM This is a an example title https://arsonline.dot.ca.gov/output1-6.php 2/2 Option: recalculate Near Fault amplification with user specified distance Site-source distance (km): 21.4 Update 1/12/22, 9:06 AM Latest Earthquakes https://earthquake.usgs.gov/earthquakes/map/?extent=-88.51252,-270&extent=88.49415,630&range=search&timeZone=utc&search=%7B"name":"Se…1/1 + − 5000 km 3000 mi Unavailable Leaet | Esri, HERE, Garmin, © OpenStreetMap contributors, and the GIS user commu… USGS Earthquakes Earthquakes loading… Only List Earthquakes Shown on Map Magnitude Format Newest First Sort 7km SSE of Big Bear City, CA 1992-06-28 15:05:30 (UTC)3.6 km6.3 17km NNE of Thousand Pal… 1992-04-23 04:50:23 (UTC)11.6 km6.1 6km SSW of Morongo Valley, … 1986-07-08 09:20:44 (UTC)9.5 km6.0 5km NNE of Ocotillo Wells, CA 1968-04-09 02:28:58 (UTC)10.0 km6.6 12km W of Salton City, CA 1954-03-19 09:54:27 (UTC)6.0 km6.4 16km E of Desert Hot Spring… 1948-12-04 23:43:16 (UTC)6.0 km6.0 16km WSW of Oasis, CA 1937-03-25 16:49:02 (UTC)6.0 km6.0 Long Beach, California Earth… 1933-03-11 01:54:09 (UTC)6.0 km6.4 2 km W of Hemet, California 1918-04-21 22:32:25 (UTC)6.8 Near San Jacinto, California 1899-12-25 12:25:00 (UTC)6.7    Earthquakes Loaded CLOSE 1/12/22, 9:05 AM 2008 National Seismic Hazard Maps - Source Parameters https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/query_results.cfm 1/5 2008 National Seismic Hazard Maps - Source Parameters New Search Distance in Kilometers Name State Pref Slip Rate (mm/yr) Dip (degrees) Dip Dir Slip Sense Rupture Top (km) Rupture Bottom (km) Length (km) 5.79 Elsinore;T+J+CM CA n/a 85 NE strike slip 0 16 169 5.79 Elsinore;T+J CA n/a 86 NE strike slip 0 17 127 5.79 Elsinore;T CA 5 90 V strike slip 0 14 52 5.79 Elsinore;GI+T+J+CM CA n/a 86 NE strike slip 0 16 195 5.79 Elsinore;W+GI+T+J+CM CA n/a 84 NE strike slip 0 16 241 5.79 Elsinore;W+GI+T+J CA n/a 84 NE strike slip 0 16 199 5.79 Elsinore;W+GI+T CA n/a 84 NE strike slip 0 14 124 5.79 Elsinore;GI+T CA 5 90 V strike slip 0 14 78 5.79 Elsinore;GI+T+J CA n/a 86 NE strike slip 0 17 153 13.24 Elsinore;J CA 3 84 NE strike slip 0 19 75 13.24 Elsinore;J+CM CA 3 84 NE strike slip 0 17 118 27.82 Elsinore;W+GI CA n/a 81 NE strike slip 0 14 83 27.82 Elsinore;GI CA 5 90 V strike slip 0 13 37 39.70 Newport-Inglewood (Oshore)CA 1.5 90 V strike slip 0 10 66 39.70 Newport Inglewood Connected alt 2 CA 1.3 90 V strike slip 0 11 208 39.70 Newport Inglewood Connected alt 1 CA 1.3 89 strike slip 0 11 208 40.99 San Jacinto;SBV+SJV+A CA n/a 90 V strike slip 0 16 134 U.S. Geological Survey - Earthquake Hazards Program 1/12/22, 9:05 AM 2008 National Seismic Hazard Maps - Source Parameters https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/query_results.cfm 2/5 40.99 San Jacinto;A CA 9 90 V strike slip 0 17 71 40.99 San Jacinto;A+CC+B+SM CA n/a 90 V strike slip 0.1 15 178 40.99 San Jacinto;A+CC+B CA n/a 90 V strike slip 0.1 15 152 40.99 San Jacinto;A+CC CA n/a 90 V strike slip 0 16 118 40.99 San Jacinto;A+C CA n/a 90 V strike slip 0 17 118 40.99 San Jacinto;SJV+A+CC+B+SM CA n/a 90 V strike slip 0.1 15 196 40.99 San Jacinto;SJV+A+CC+B CA n/a 90 V strike slip 0.1 15 170 40.99 San Jacinto;SBV+SJV+A+CC+B CA n/a 90 V strike slip 0.1 15 215 40.99 San Jacinto;SBV+SJV+A+CC CA n/a 90 V strike slip 0 16 181 40.99 San Jacinto;SBV+SJV+A+C CA n/a 90 V strike slip 0 17 181 40.99 San Jacinto;SJV+A+CC CA n/a 90 V strike slip 0 16 136 40.99 San Jacinto;SJV+A+C CA n/a 90 V strike slip 0 17 136 40.99 San Jacinto;SJV+A CA n/a 90 V strike slip 0 17 89 40.99 San Jacinto;SBV+SJV+A+CC+B+SM CA n/a 90 V strike slip 0.1 15 241 42.25 Rose Canyon CA 1.5 90 V strike slip 0 8 70 43.58 San Jacinto;SJV CA 18 90 V strike slip 0 16 43 43.58 San Jacinto;SBV+SJV CA n/a 90 V strike slip 0 16 88 54.50 San Jacinto;CC CA 4 90 V strike slip 0 16 43 54.50 San Jacinto;CC+B CA n/a 90 V strike slip 0.2 14 77 54.50 San Jacinto;CC+B+SM CA n/a 90 V strike slip 0.2 14 103 55.12 San Joaquin Hills CA 0.5 23 SW thrust 2 13 27 56.24 Earthquake Valley CA 2 90 V strike slip 0 19 20 1/12/22, 9:05 AM 2008 National Seismic Hazard Maps - Source Parameters https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/query_results.cfm 3/5 57.55 San Jacinto;C CA 14 90 V strike slip 0 17 47 61.58 Chino, alt 2 CA 1 65 SW strike slip 0 14 29 63.48 Elsinore;W CA 2.5 75 NE strike slip 0 14 46 65.80 Chino, alt 1 CA 1 50 SW strike slip 0 9 24 66.81 S. San Andreas;BG CA n/a 58 strike slip 0 13 56 66.81 S. San Andreas;NSB+SSB+BG+CO CA n/a 79 strike slip 0.2 12 206 66.81 S. San Andreas;SSB+BG CA n/a 71 strike slip 0 13 101 66.81 S. San Andreas;CH+CC+BB+NM+SM+NSB+SSB+BG+CO CA n/a 86 strike slip 0.1 13 512 66.81 S. San Andreas;BG+CO CA n/a 72 strike slip 0.3 12 125 66.81 S. San Andreas;CC+BB+NM+SM+NSB+SSB+BG CA n/a 85 strike slip 0 14 380 66.81 S. San Andreas;CC+BB+NM+SM+NSB+SSB+BG+CO CA n/a 86 strike slip 0.1 13 449 66.81 S. San Andreas;CH+CC+BB+NM+SM+NSB+SSB+BG CA n/a 86 strike slip 0 14 442 66.81 S. San Andreas;NM+SM+NSB+SSB+BG CA n/a 83 strike slip 0 14 271 66.81 S. San Andreas;NM+SM+NSB+SSB+BG+CO CA n/a 84 strike slip 0.1 13 340 66.81 S. San Andreas;NSB+SSB+BG CA n/a 75 strike slip 0 14 136 66.81 S. San Andreas;PK+CH+CC+BB+NM+SM+NSB+SSB+BG CA n/a 86 strike slip 0.1 13 479 66.81 S. San Andreas;PK+CH+CC+BB+NM+SM+NSB+SSB+BG+CO CA n/a 86 strike slip 0.1 13 548 66.81 S. San Andreas;SM+NSB+SSB+BG CA n/a 81 strike slip 0 13 234 66.81 S. San Andreas;SM+NSB+SSB+BG+CO CA n/a 83 strike slip 0.1 13 303 66.81 S. San Andreas;SSB+BG+CO CA n/a 77 strike slip 0.2 12 170 66.81 S. San Andreas;BB+NM+SM+NSB+SSB+BG CA n/a 84 strike slip 0 14 321 1/12/22, 9:05 AM 2008 National Seismic Hazard Maps - Source Parameters https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/query_results.cfm 4/5 66.81 S. San Andreas;BB+NM+SM+NSB+SSB+BG+CO CA n/a 85 strike slip 0.1 13 390 67.22 S. San Andreas;CH+CC+BB+NM+SM+NSB+SSB CA n/a 90 V strike slip 0 14 384 67.22 S. San Andreas;SM+NSB+SSB CA n/a 90 V strike slip 0 13 176 67.22 S. San Andreas;NM+SM+NSB+SSB CA n/a 90 V strike slip 0 13 213 67.22 S. San Andreas;PK+CH+CC+BB+NM+SM+NSB+SSB CA n/a 90 V strike slip 0.1 13 421 67.22 S. San Andreas;NSB+SSB CA n/a 90 V strike slip 0 13 79 67.22 S. San Andreas;CC+BB+NM+SM+NSB+SSB CA n/a 90 V strike slip 0 14 322 67.22 S. San Andreas;BB+NM+SM+NSB+SSB CA n/a 90 V strike slip 0 14 263 67.22 S. San Andreas;SSB CA 16 90 V strike slip 0 13 43 67.42 Coronado Bank CA 3 90 V strike slip 0 9 186 67.42 Palos Verdes Connected CA 3 90 V strike slip 0 10 285 68.21 San Jacinto;SBV CA 6 90 V strike slip 0 16 45 75.13 Palos Verdes CA 3 90 V strike slip 0 14 99 78.49 Newport-Inglewood, alt 1 CA 1 88 strike slip 0 15 65 80.82 Pinto Mtn CA 2.5 90 V strike slip 0 16 74 82.66 S. San Andreas;CH+CC+BB+NM+SM+NSB CA n/a 90 V strike slip 0 14 341 82.66 S. San Andreas;NSB CA 22 90 V strike slip 0 13 35 82.66 S. San Andreas;CC+BB+NM+SM+NSB CA n/a 90 V strike slip 0 14 279 82.66 S. San Andreas;PK+CH+CC+BB+NM+SM+NSB CA n/a 90 V strike slip 0.1 13 377 82.66 S. San Andreas;NM+SM+NSB CA n/a 90 V strike slip 0 13 170 82.66 S. San Andreas;BB+NM+SM+NSB CA n/a 90 V strike slip 0 14 220 82.66 S. San Andreas;SM+NSB CA n/a 90 V strike 0 13 133 1/12/22, 9:05 AM 2008 National Seismic Hazard Maps - Source Parameters https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/query_results.cfm 5/5 slip 87.63 Puente Hills (Coyote Hills)CA 0.7 26 N thrust 2.8 15 17 87.88 Elsinore;CM CA 3 82 NE strike slip 0 13 39 88.55 San Jacinto;B+SM CA n/a 90 V strike slip 0.4 12 61 88.55 San Jacinto;B CA 4 90 V strike slip 0.7 13 34 89.64 Burnt Mtn CA 0.6 67 W strike slip 0 16 21 90.08 Cucamonga CA 5 45 N thrust 0 8 28 91.74 S. San Andreas;CO CA 20 90 V strike slip 0.6 11 69 93.61 San Jose CA 0.5 74 NW strike slip 0 15 20 94.92 Eureka Peak CA 0.6 90 V strike slip 0 15 19 96.75 Cleghorn CA 3 90 V strike slip 0 16 25 97.55 Sierra Madre Connected CA 2 51 reverse 0 14 76 97.55 Sierra Madre CA 2 53 N reverse 0 14 57 APPENDIX E SLOPE STABILITY ANALYSIS Pauba Formation Compacted Fill Slope 214152-10 Lolita Road SFR Cross Section A-A' Proposed Pad Area Distance 0 20 40 60 80 100 120 140 160 1,150 1,170 1,190 1,210 El e v a t i o n 1,150 1,170 1,190 1,210 1.732 Pauba Formation Compacted Fill Slope 214152-10 Lolita Road SFR Cross Section A-A' Static Analysis Factor of Safety = 1.732 Proposed Pad Area Distance 0 20 40 60 80 100 120 140 160 1,150 1,170 1,190 1,210 El e v a t i o n 1,150 1,170 1,190 1,210 1.202 Pauba Formation Compacted Fill Slope 214152-10 Lolita Road SFR Cross Section A-A' Pseudo Static Analysis Factor of Safety = 1.202 Proposed Pad Area Distance 0 20 40 60 80 100 120 140 160 1,150 1,170 1,190 1,210 El e v a t i o n 1,150 1,170 1,190 1,210 1.818 Pauba Formation Proposed Cut Slope Proposed Pad Area 214152-10 Lolita Road SFR Cross Section B-B' Static Analysis Factor of Safety = 1.818 Distance 0 20 40 60 80 100 120 140 160 180 1,180 1,200 1,220 1,240 El e v a t i o n 1,180 1,200 1,220 1,240 1.208 Pauba Formation Proposed Cut Slope Proposed Pad Area 214152-10 Lolita Road SFR Cross Section B-B' Pseudo Static Analysis Factor of Safety = 1.208 Distance 0 20 40 60 80 100 120 140 160 180 1,180 1,200 1,220 1,240 El e v a t i o n 1,180 1,200 1,220 1,240 APPENDIX F GENERAL EARTHWORK AND GRADING SPECIFICATIONS B-2 T.D. = 5' NO G.W. B-1 T.D. = 5' NO G.W. B-3 T.D. = 4' NO G.W. Qps 5-7' B ' B A ' A LEGEND Locations are Approximate Geologic Units Symbols -Recommended Removal Depths -Boring Location Including Total Depth and Depth to Groundwater 5-7' B-3 T.D. = 4' NO G.W. -Limits of Report Qps -Quaternary Pauba Formation -Cross Section LocationBB' PROJECT CLIENT PROJECT NO. SCALE DATE DRAWN BY DWG XREFS REVISION PLATE PROPOSED SINGLE FAMILY RESIDENCE MR. BRUO NASCIMENTO 214152-10A FEBRUARY 2022 1" = 40' 1 OF 1 GEOTECHNICAL MAP LOCATED NORTH OF LOLITA ROAD CITY OF TEMECULA, RIVERSIDE COUNTY, CALIFORNIA APN 945-140-010 JDG Geotechnical, Environmental and Materials Testing Consultants www.ESGSINC.com (951) 397-8315 Earth Strata Geotechnical Services, Inc. 0 20 40 80 SCALE: 1" = 40' NO R T H