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Home My WebLink AboutPA2023-0064_20230316_Geo Report dated 02-10-2023TABLE OF CONTENTS 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com Contents INTRODUCTION ............................................................................................................................................. 1 SCOPE OF WORK ........................................................................................................................................... 1 SITE LOCATION AND DESCRIPTION ............................................................................................................... 1 Vicinity Map - Figure 1 .............................................................................................................................. 2 PROJECT DESCRIPTION .................................................................................................................................. 3 REGIONAL GEOLOGIC SETTING ..................................................................................................................... 3 Regional Geologic Map - Figure 2 ............................................................................................................. 4 SUBSURFACE CONDITIONS ........................................................................................................................... 4 Earth Materials.......................................................................................................................................... 4 Groundwater ............................................................................................................................................. 5 Caving ........................................................................................................................................................ 5 Consolidation ............................................................................................................................................ 5 Expansion Potential .................................................................................................................................. 5 Water-Soluble Sulfate ............................................................................................................................... 5 GEOLOGIC HAZARDS ..................................................................................................................................... 6 Faulting/Fault Rupture .............................................................................................................................. 6 Liquefaction/Seismically Induced Settlement .......................................................................................... 6 Tsunami Potential ..................................................................................................................................... 6 Earthquake Induced Landslide Potential .................................................................................................. 6 Slope Stability ............................................................................................................................................ 6 CONCLUSIONS AND RECOMMENDATIONS ................................................................................................... 7 Site Clearing and Grading .......................................................................................................................... 7 Seismic Design ........................................................................................................................................... 8 Slope Setback ............................................................................................................................................ 8 Foundation Design .................................................................................................................................... 9 Floor Slab Design/Construction .............................................................................................................. 10 Conventional Retaining Wall Design ....................................................................................................... 10 Settlement .............................................................................................................................................. 12 Temporary Slopes ................................................................................................................................... 12 Permanent and Temporary Shoring ....................................................................................................... 12 Concrete Flatwork/Driveway .................................................................................................................. 13 TABLE OF CONTENTS 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com Spa ........................................................................................................................................................... 13 Concrete Quality ..................................................................................................................................... 14 Site Drainage ........................................................................................................................................... 14 Plan Review ............................................................................................................................................. 14 Observations and Testing ....................................................................................................................... 14 Miscellaneous Backfills ........................................................................................................................... 14 Pre-Grade/Construction Meeting ........................................................................................................... 15 GENERAL COMMENTS................................................................................................................................. 15 REFERENCES ................................................................................................................................................ 16 APPENDIX A ................................................................................................................................................. 17 FIELD INVESTIGATION ................................................................................................................................. 17 APPENDIX B ................................................................................................................................................. 19 LABORATORY PROCEDURES & TEST RESULTS ............................................................................................. 19 Moisture and Density Determination (ASTM D2216-10 & 7263-09) ...................................................... 20 Expansion Index Test (ASTM D4829-11) ................................................................................................. 20 Water-Soluble Sulfate Test (EPA 300.0) .................................................................................................. 20 Compaction Test (ASTM D1557-12ɛ1) ..................................................................................................... 20 Consolidation Tests (ASTM D2435/D2435 M-11) ................................................................................... 20 Direct Shear (ASTM D3080/D3080 M-11) ............................................................................................... 20 SAMPLE STORAGE ....................................................................................................................................... 21 APPENDIX C ................................................................................................................................................. 22 SEISMIC DATA AND RESPONSE SPECTRUM ................................................................................................ 22 APPENDIX D ................................................................................................................................................. 23 SLOPE STABILITY ANALYSES ........................................................................................................................ 23 FIGURE NAME LOCATION Plate A-1a Geotechnical Map Appendix A Plate A-1b Cross Section Appendix A Plates A-2 and A-3 Boring Logs Appendix A Plate A-4 Unified Soil Classification Symbols/Descriptions Appendix A Plate B-1 Consolidation Curve Appendix B Plates B-2 and B-3 Direct Shear Diagrams Appendix B OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 1 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com INTRODUCTION This report presents the results of a geotechnical investigation of the subject construction areas. The purposes of the investigation were to: 1) determine the type and condition of the earth materials underlying the site; 2) establish static physical and limited chemical properties of the materials; 3) determine groundwater conditions; and 4) provide recommendations for design and construction of the foundation and floor slab for the proposed first, second, and third-story additions including garage to the existing three-story single family residence and soil parameters for the new rear-yard spa and attendant improvements. SCOPE OF WORK The scope of work for this geotechnical investigation consisted of the following: Review of published regional geologic maps and reports (See References). A field exploration was conducted on January 13, 2023 which consisted of excavating, sampling, and logging two small-diameter exploratory borings (B-1 through B-2) to depths of up to 5 feet. In addition surface geologic mapping of exposed bedrock on the property was performed. The field exploration is described in detail in Appendix A. Selected samples were tested in HGEI’s AMRL Accredited Geotechnical Laboratory to develop data necessary for analysis of subsurface conditions and used in preparation of this report. A description of the geotechnical laboratory testing conducted for the samples collected from the site and presentation of the results are found in the Laboratory Procedures & Test Results in Appendix B. HGEI conducted engineering analysis, constructed figures, and prepared this report depicting the findings and conclusions of the investigation. SITE LOCATION AND DESCRIPTION The site is located at 2607 Ocean Blvd, Corona Del Mar, CA as shown on the Vicinity Map, Figure 1, which follows. There is currently a three-story single-family residence on the terraced lot that was reportedly constructed in 1947 (Zillow). The parcel is located along the northeast side of the entrance channel to Newport Harbor and is built into the generally southwesterly descending coastal bluff. The property is bordered to the southwest by Way Lane, to the northeast by Fernleaf Ramp and Ocean Blvd., and the east and west by similar single family residences on terraced bluff-face lots. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 2 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com The sloping property ascends approximately 40 vertical feet at variable gradients of 2:1 (horizontal:vertical) to nearly vertical (beneath the crawl-space below the existing deck) from Way Lane to Fernleaf Ramp above. Grade changes are accommodated by building and yard retaining walls and slopes. A relatively level path traverses the slope above the existing residence. The yard is landscaped with dense brush and scattered trees. A review of the City of Newport Beach Community Development files revealed no geotechnical documents pertaining to the original grading and development of the property. Vicinity Map - Figure 1 OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 3 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com PROJECT DESCRIPTION The remodel comprises the additions of a 424 SF garage and 23 SF entry to the first floor which is at Way Lane level, 337 SF to the second floor and 682 SF to the third floor. In addition new decks are proposed including a roof-top deck and a new rear-yard spa north of the house. Spa plans were not available at the time this report was prepared. Grading involves excavating into the hillside to create a level pad for construction of the three- story addition. It appears that significant cuts will be necessary. The foundation will likely consist of continuous perimeter footings with both slab on grade and raised wood floors as well as retaining walls which may be constructed as permanent shoring walls or conventional retaining walls. Building loads were not available during preparation of this report, as such, we have assumed a maximum bearing wall loads of 2,000 pounds per lineal foot. If the actual design loads significantly exceed the assumed value they should be provided to the geotechnical engineer for further analysis and review of potential settlement. Associated improvements include a new driveway and hardscape/landscape areas. REGIONAL GEOLOGIC SETTING The subject site is situated along the northwesterly portion of the Peninsular Ranges Geomorphic Province of Southern California near the Pacific Ocean. The Peninsular Ranges Geomorphic Province is characterized by elongated northwest to southeast trending ridges and valleys subparallel to faults branching from the San Andreas Fault. Published maps (Reference 4) have been used to identify the geologic units underlying the property. As shown in Figure 2, these maps indicate that the property is underlain by bedrock of the Monterey Formation of Miocene geologic age which is overlain by old paralic deposits (Qop) of late to middle Pleistocene geologic age. Paralic deposits are inter-fingered marine and continental sediments deposited on the landward side of the coast, commonly in an estuary environment. Bedrock exposed in outcrops during our investigation is comprised of weathered and thinly bedded cemented siltstone, shale and chert that is heavily and tightly folded. Geologic structure in outcrops was observed to be highly variable, due to folding, with some areas exhibiting over- turning of beds. There are no records of landslides mapped on or near the property. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 4 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com Regional Geologic Map - Figure 2 Qop – Old Paralic Deposits (late to middle Pleistocene) - Silt, sand and cobbles. Interfingered strandline, beach, estuarine, and colluvial deposits. Tm – Monterey Formation (Miocene) - Marine Siltstone and Sandstone; Siliceous and diatomaceous (Miocene) SUBSURFACE CONDITIONS Earth Materials Subsurface conditions encountered during this investigation are described in more detail in Appendix A. The subsurface exploration locations and surface geologic conditions are indicated on Plate A-1a and Cross Section A-A’ (Plate A-1b) was drawn to show the subsurface conditions. Logs of the borings are presented on Plates A-2 through A-3 and show the site to be immediately underlain by shallow old paralic deposits near the upper portion of the site and bedrock below. SITE OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 5 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com Topsoil/Old Paralic Deposits (Qop) was observed mantling the upper portion of the lot and is comprised of brown and light orange/white fine to medium grained silty sand and sand that is damp to moist and loose and has significant roots. The soil materials were generally less than 5 feet deep. Bedrock comprised of the Monterey Formation (Tm) was observed on the surface in the lower portions of the lot and beneath the upper soils at a maximum depth of approximately 5 feet in B-2. Bedrock is comprised of white/light orange thinly bedded and cemented siltstone, shale and chert that is heavily and tightly folded and is damp and very hard. Geologic structure in outcrops was observed to be highly variable, due to folding, with some areas exhibiting over- turning of beds. Due to the well indurated nature of the materials, the bedrock could not be penetrated with the hand excavating equipment used. Groundwater Groundwater was not encountered in any borings at the time of recent exploration and is not expected to adversely affect the proposed development under normal conditions in the future. Historic groundwater depth in the area is reported to be in excess of 10 feet (Reference 1). Caving Caving of the exploratory borings did not occur. Due to the presence of relatively shallow dense bedrock, caving is not expected to be a major concern during construction. The regulations of Cal/OSHA should be complied with during performance of all underground construction. Consolidation A sample of soil was loaded in increments from 400 to 6400 pounds per square foot (psf) at its overburden pressure and was saturated to determine its hydro-collapse or expansion potential. The sample (B-2 @ 2.5’) exhibited minor hydro-collapse potential. Expansion Potential Based on the results of laboratory testing (Table 1, Appendix B) the Expansion Index for the typical near-surface material is 1. The 2022 California Building Code (Section 1803.5.3) categorizes this material as being non- expansive and therefore no special design is required. Water-Soluble Sulfate A soil sample was delivered to a state approved analytical laboratory for testing to evaluate water-soluble sulfate content. Based on the results of laboratory testing (Table 2, Appendix B) an exposure category of S0 is indicated (ACI 318-19, Table 19.3.1.1). OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 6 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com GEOLOGIC HAZARDS Faulting/Fault Rupture The site is in a portion of California that is seismically active and anticipated to be subjected to strong ground motions by earthquakes generated by active faults in the area. The site is not within a presently designated earthquake fault zone as established by the Alquist-Priolo Fault Zoning Act (References 2 and 3). The site is situated approximately 2.7 km away from the nearest fault (Newport-Inglewood Offshore) and the likelihood of surface rupture occurring at the site is considered low. Liquefaction/Seismically Induced Settlement The site is not located in a potential liquefaction hazard zone as shown on the State of California Earthquake Zones of Required Investigation, Newport Beach Quadrangle Sheet (References 2 and 3). Therefore, a liquefaction/dry sand settlement assessment was not conducted. Tsunami Potential The likelihood of the site being affected by a tsunami during a seismic event is a possibility according to CGS Information Warehouse, Tsunami Hazard Area Map Application (Reference 3). The application indicates that the site is within the mapped hazard area of tsunami inundation. This is due to the close proximity to the coastline and relatively low elevation of the site. Emergency alerts should be heeded and possible evacuation routes assessed ahead of time. Earthquake Induced Landslide Potential As shown on the State of California Earthquake Zones of Required Investigation, Newport Beach Quadrangle Sheet (References 2 and 3), the property is located within a potential earthquake induced landslide zone. Refer to slope stability during a seismic event below. Slope Stability Cross Section A-A’ (Plate A-1b) was drawn to show the subsurface conditions. As depicted on A-A’, the proposed addition will be located in an overall 40-foot high slope. The stability of the slope was evaluated using GStabl7.0 computer program. The slope was evaluated along Section A-A’ for the proposed geometry for the southwesterly facing slope. The proposed retaining walls were modeled as vertical cuts with concrete walls and evaluated using circular analysis modes under both static and seismic (pseudo-static) loading conditions. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 7 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com A pseudo-static coefficient of 0.235g was selected based on keq (Reference 6, Page 29) with a displacement of 15 cm and shear strength parameters for the soils were determined based on the results of direct shear testing. Shear strength parameters for bedrock were informed by CGS published parameters (Reference 1) and experience in the area. The analyses results in a static factor of safety of 1.525 and a seismic factor of safety of 1.129. These values exceed City minimums of 1.5 and 1.0, for static and pseudo-static, respectively. The analyses and associated output are presented in Appendix D. CONCLUSIONS AND RECOMMENDATIONS Based on conditions encountered/established during this investigation, it is our conclusion that construction of the currently planned addition and miscellaneous improvements are feasible from a geotechnical engineering standpoint provided the recommendations which follow are implemented during design and construction of the project. Following our evaluation of conditions encountered in the field exploration and the analyses of laboratory test data, the following recommendations for grading and developing the site are being provided. The following recommendations reflect our best assessment of project conditions and requirements based on analysis and evaluation of results reported herein. Anticipated conditions and these recommendations are subject to confirmation during grading and/or construction. Additional recommendations may be provided during the course of work if warranted by conditions encountered. The grading and foundation plans should be reviewed by the geotechnical engineer and any necessary recommendations provided in a review letter. Site Clearing and Grading It is anticipated that grading will primarily involve cutting into the hillside to create a level pad. The underlying bedrock materials will be suitable to support the proposed addition and spa. Prior to grading, any existing vegetation and debris resulting from removal of the prior retaining walls and deck should be stripped and disposed of offsite according to the city’s requirements. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 8 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com It should be anticipated that the cuts required to achieve proposed grades will be very difficult to excavate due to the well indurated materials on-site. Appropriate excavating equipment should be utilized. Shoring will also be necessary. If any fill is required, the exposed bedrock should be scarified 12 inches deep, moisture conditioned to its optimum moisture content, and compacted to a minimum relative compaction of 90% based on the results of compaction tests performed in accordance with ASTM Test Method D1557-12ɛ1. Fill material should be spread in thin, loose lifts (approximately 6” thick), and moisture conditioned and compacted as indicated above. Additional compaction tests should be performed as necessary for proper control during grading and to confirm the data in Table 3 of Appendix B. If imported soil is required it should be approved by the geotechnical engineer for expansion and sulfate qualities prior to being transported to the project site. Final acceptance of any imported soil will be based on observation and/or testing of soil actually delivered to the site. It is recommended that grading operations be monitored by a representative of this office in order to confirm compliance with these recommendations and, in turn, the foundation design recommendations which follow. Seismic Design The provisions of Chapter 16, Section 1613, of the 2022 California Building Code and the Structural Engineer Associates of California guidelines are considered appropriate for design of the project. Earthquake factors were determined using the ASCE and Structural Engineers of California data base websites and Chapter 16 requirements and are presented in Appendix C. Slope Setback Structural setbacks from the ascending slope should conform to the 2022 California Building Code Setback Details Sections 1808.7.1-1808.7.3 which stipulates a setback of H/2 (where H is the height of the slope) but not to exceed 15 feet for the residence. Based on preliminary plans, it appears that the ascending slope above the top of the structural retaining wall is approximately 10 feet high. This would require a 5-foot slope setback. The current plans indicate a minimum setback of 5 feet for the proposed addition from the toe of the ascending slope and therefore this setback is being met. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 9 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com Structural setbacks from the descending slope should conform to the 2022 California Building Code Setback Details Sections 1808.7.1-1808.7.3 which stipulates a setback of H/3 (where H is the height of the slope) but not to exceed 40 feet. The outer 3 feet of the slope which is prone to erosion and raveling should be excluded from the setback zone. The setback is measured from the bottom of the foundation to the face of the slope. Based on preliminary plans, it appears that the descending slope below the westerly portion of the proposed addition, which is not underlain by ground-floor garage, is approximately 20 feet in height. This would be an approximate 10-foot setback (7 feet plus 3 feet for erosion), measured from the bottom of the foundation to the face of the slope. With a 1:1 slope in this area, deepened foundation elements on the order of approximately 10 feet will be needed to achieve the recommended 20-foot setback. Foundation Design The following recommendations are based on our anticipation that bedrock will be exposed at foundation grades and that the foundation will be entirely founded on bedrock. New conventional footings embedded into approved bedrock may be used. Footings with a minimum width of 18 inches and plan dimension depth of 24 inches for three-story (measured from the lowest adjacent finish grade) may be designed using an allowable, net, dead load plus live load soil bearing pressure up to 2,000 pounds per square foot (psf). The allowable soil bearing pressure can be increased by 250 psf for each additional foot of width or depth to a maximum allowable bearing capacity of 3,000 psf if deemed necessary by the structural engineer. A one-third increase in bearing may be assumed for short duration wind or seismic loading in combination with vertical loads. The garage door and other large openings should be provided with a continuous footing across the opening matching the minimum footing dimensions above. The foundation for the portions of the new structure which are not underlain by the ground- floor garage and require deepened foundation elements to achieve slope setback may require short piers up to approximately 10 feet deep. Pier footings at least 18 inches diameter which will be founded in bedrock may be designed using an allowable, net, dead load plus live load soil bearing pressure of up to 5,000 pounds per square foot and an allowable 250 pounds per square foot for skin friction. A one-third increase in bearing may be assumed for short duration wind or seismic loading in combination with vertical loads. The piers should be connected by a series of grade beams. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 10 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com For the purposes of resisting lateral forces, an allowable passive soil pressure of 250 pounds per square foot per foot of depth may be used in design. An allowable coefficient of friction of 0.35 may be used for concrete placed on approved bedrock materials. These values may be combined without reduction. An appropriate safety factor must be applied. It is recommended that continuous footings be reinforced with at least two No. 4 bar, top and bottom. Reinforcement of pier or pad footings should be determined by the structural engineer. Where new foundation elements (slab and footing) abut existing foundation elements, the new foundations should be doweled into the existing foundations. Dowel size, spacing, embedment, and adhesion materials (grout, epoxy) are deferred to the foundation designer. It is recommended that the foundation excavations be examined and, if necessary, tested by a representative of the geotechnical engineer to confirm anticipated conditions and/or provide additional recommendations should they be necessary. Floor Slab Design/Construction It is recommended that the floor slab be a nominal 4 inches thick, reinforced with No. 4 bars at 18 inches on center, each way. A moisture vapor retarder installed in accordance with the manufacturer’s instructions should be provided for living areas. We would recommend that 2 inches of clean sand be placed over a minimum 10 mil visqueen vapor barrier underlain by 4 inches of coarse sand or gravel to comply with the requirements of CALGREEN. HGEI does not practice in the field of moisture vapor transmission evaluation/mitigation and recommends that a qualified consultant be engaged to evaluate the general and specific moisture vapor transmission paths and provide recommendations for mitigation of potential adverse impact of moisture vapor transmission. It is cautioned that any slab areas to receive ceramic tile or other rigid, crack-sensitive floor covering must be designed and constructed to minimize hairline cracking. Extra reinforcing steel and careful control of concrete slump to minimize shrinkage is recommended. Conventional Retaining Wall Design Retaining wall footings should be underlain by bedrock and be bottomed at least 24 inches below the lowest adjacent grade. An allowable, net, soil bearing pressure of 2,000 pounds per square foot may be used for footings at least 24 inches wide and bottomed at the OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 11 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com recommended minimum depth. This value may be increased 250 pounds per square foot for each additional foot of width up to a maximum value of 3,000 pounds per square foot. A one- third increase in bearing may be assumed when considering transient loads due to wind pressure or seismic forces in combination with vertical loads. Passive resistance below a depth of two foot may be determined using an allowable passive pressure taken as an equivalent fluid density of 250 pounds per square foot per foot of depth. A friction coefficient of 0.35 may be used. These values may be combined without reduction. Due to typical construction methods and sequence on similar projects, we anticipate that retaining walls will be backfilled with gravel. Where walls are free to rotate, they may be designed using an active lateral earth pressure of 30 pounds per square foot per foot of depth for level backfill and 45 pounds per square foot per foot of depth for (2H:1V) sloping backfill. For the design of retaining walls that are restrained from rotating, the 2022 Building Code (Section 1610.11) requires that the walls be designed for the at-rest pressure which in this case is 45 pounds per square foot per foot of depth for the level condition and 65 pounds per square foot per foot of depth for 2:1 sloped backfill. The 2022 California Building Code (Section 1803.5.12) requires that earthquake forces be included in design of the retaining wall should the retained height equal or exceed 6 feet. In this regard, it is recommended that a dynamic increment of active force equal to 38 pcf acting as an inverted triangle be added to the static pressure. The retained height is measured from the bottom of the footing to the finished soil grade at the rear face of the wall. Retaining walls should be waterproofed if the possibility of efflorescence developing on the exposed faces is unacceptable. Subdrains consisting of a 4-inch-diameter, perforated, schedule 40 PVC pipe surrounded with one cubic foot/foot of drain rock wrapped in geofabric should be provided for the walls. The location of the subdrain outlet should be determined by the civil engineer. Other specialty wall drains (subdrains) can be used in lieu of the pipe and gravel with the approval of the geotechnical engineer. Approved wall backfill materials should be placed in thin lifts, moisture conditioned to near- optimum moisture content and mechanically compacted to at least 90% of the maximum density determined by ASTM Test Method D1557. Continuous benches at least one foot wide should be cut into the existing soil during backfilling to interlock the materials. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 12 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com Settlement Building foundation settlement (total and differential) should not exceed ½ inch and ¼ inch respectively provided footings are founded in bedrock. The horizontal distance over which differential settlement could occur is 20 feet. Relatively minor settlement of the addition relative to the existing residence, most of which is expected to be complete by the end of construction, should be anticipated and may result in minor cosmetic damage to the existing structure. Temporary Slopes Temporary slopes may be cut 5-foot vertical at the toe with the remainder above laid back at a 1:1 gradient. As there does not appear to be adequate room to follow these guidelines, we anticipate that shoring will be necessary. Temporary cuts should be monitored during grading/construction by a representative of this office in order to confirm these recommendations. Permanent and Temporary Shoring It is anticipated that shoring will be required for the excavation which is adjacent to the existing residence. At this time, no plans have been shared that would indicate whether the project will utilize permanent or temporary shoring; parameters for both are provided herein. For cantilevered shoring supporting Monterey Formation bedrock a triangular stress distribution of lateral earth pressure may be used. It may be assumed that the retained soils with a level surface behind the cantilevered shoring will exert an equivalent active fluid pressure of 30 pcf. In the event that male/reentrant corners are present the equivalent at rest fluid pressure at those locations should be 45 pcf. Cantilevered shoring will deflect as the excavation is made. Deflections can vary from 0.3% to 1% which, based on the maximum excavated depth. The proximity to the adjacent existing structure will determine whether this is acceptable. The impact of excavations on the existing adjacent structure will need to be addressed by the shoring and structural engineers. Soldier piles/Cast-in-Drilled-Hole (CIDH) Piers should be embedded a minimum of 10-feet below the bottom of the planned excavation into approved bedrock materials. For the design of Soldier Piles/CIDS Piers, the allowable passive bearing pressure below the level of the excavation may be assumed to be 250 psf/ft of depth up to a maximum of 3,000 psf. Where piles/piers are spaced a minimum 3-diameters on-center, the passive pressure may be applied OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 13 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com over twice the pile/pier diameter. We expect that temporary piles will be filled with lean cement/sand slurry (1- 1/2 to 2 sack mix). Continuous lagging or plates will be required between soldier piles. The piles/piers should be designed for the full anticipated lateral earth pressure including the effect of any surcharge. However, the pressure on the lagging will be lower due to arching. We recommend that the lagging be designed for the recommended earth pressure but limited to a maximum value of 400 psf. The pressure distribution of the lagging may be assumed to be semi-circular, where the pressure at the soldier pile is 0 and the pressure at the center is 400 psf. Concrete Flatwork/Driveway Miscellaneous flatwork should be a nominal 4 inches thick, reinforced at mid-depth with No 4 bars at 18-inches on center each way and provided with adequate control joints. Low slump concrete should be used for all flatwork to further minimize cracking. The driveway thickness should be 5 inches if constructed of concrete. It should be noted that due to normal concrete shrinkage some minor cracking of the concrete flatwork may occur. Additional reinforcement beyond that recommended herein and careful control of concrete slump would be beneficial in reducing such cracking. Also, it is very important that all control joints be caulked and properly maintained to inhibit infiltration of surface water into the soil and thereby minimize expansion. Spa It is recommended that the new spa be supported entirely on bedrock. Excavation for the spa, including the placement of drains, outlets, pipes, as well as other various utility installations, should be performed under the observation of our firm in order to verify that the conditions exposed in the excavation and backfills are consistent with design assumptions. Due to the indicated low expansion potential the spa shell supporting level ground should be designed for an equivalent fluid pressure of 60 psf/ft when empty. The equivalent fluid pressure was based on the at rest pressure which was calculated as KO =1-sin (Ф) which is 1-sin (30°) = 0.50. Therefore the EFP =0.50x 120= 60.0 psf/ft. Surcharge loads, if any, should be incorporated by the designer. A hydrostatic pressure relief value should be provided due to the relatively impervious subgrade material. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 14 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com Final spa plans should be forwarded to our office for review prior to construction. Revised recommendations based on the final spa location and configuration may be warranted. Concrete Quality A negligible amount of water-soluble sulfate is indicated for the prevalent surface material and special sulfate-resistant concrete will not be required on this project. The exposure class (ACI 318-19, Table 19.3.1.1) is S0. Based on this test result concrete may contain Type II cement per Section 1904.2 of the 2022 CBC and ACI 318-19, Table 19.3.2.1. Site Drainage The 2022 CBC Section 1804.4 requires that the minimum drainage for the ground around the perimeter of a building should be 5% away from the foundation for a distance of 10 feet. Impervious surfaces within 10 feet of the building foundation shall be sloped a minimum of 2%. In no case should the surface waters be allowed to flow over the slope surfaces in an uncontrolled manner. Plan Review It is recommended that final project plans, details and specifications be submitted to this office for geotechnical review for compliance with the findings and recommendations of this report. Additional recommendations can then be provided if necessary. Observations and Testing Grading, foundation construction, and trench backfills should be observed and tested by members of our staff so that anticipated soil conditions can be confirmed and the recommendations contained herein validated. If deemed necessary, as a result of changed conditions, supplemental recommendations may then be provided. Results of those observations and tests should be provided in the final report which should include a statement by the geotechnical engineer concerning the adequacy of the completed work. Miscellaneous Backfills Backfill for structural excavations and utility trenches associated with this project should consist of site material (the use of imported sand is not recommended) that must be adequately compacted to preclude detrimental settlement. It is recommended, therefore, that backfills placed below the building foundation and to a distance of five feet outside thereof, and/or below concrete flatwork, be placed in appropriate lifts, moisture conditioned and mechanically compacted to at least 90 percent of maximum dry density. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 15 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com Pre-Grade/Construction Meeting A pre-grade/construction meeting attended by the owner or his authorized representative, members of the design team, grading contractor, city/county inspector, and a representative from HGEI at the site to review the findings and recommendations of this report and project plans and specifications prior to starting work on the project. GENERAL COMMENTS The services provided under the purview of this report have been performed in accordance with generally accepted geotechnical engineering principals and standards of practice in this area. The comments and recommendations presented are professional opinions based on observations and our best estimation of project conditions and requirements as indicated by presently available information and data. No further warranty, express or implied, is intended by issuance of this report. The investigation did not include: 1) detailed study of geologic and seismic conditions; 2) assessment of the liquefaction potential (site is not in a mapped zone); or 3) sampling, field measurements or laboratory tests for the presence of any toxic/hazardous substances in the earth materials at the site. However, this does not imply that the site is subject to any unusual geologic, seismic or environmental hazard. Any unanticipated condition encountered in the course of grading and/or construction should be brought to the attention of the geotechnical engineer for evaluation prior to proceeding with the work. This report has been developed for the sole use of the client and/or clients authorized representative. These conclusions and recommendations should be verified by a qualified geotechnical engineer based in part upon additional subsurface information obtained during grading and/or foundation construction. No part of the report should be taken out of context, nor utilized without full knowledge and awareness of its intent. This report is issued on the condition that HGEI will be retained to observe the grading and foundation construction. If another firm provides this service that firm must review and accept this report, or provide alternate recommendations, and assume responsibility for the project. This report will be valid for a period of one year form date of issue and will then require updating. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 16 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com REFERENCES 1. California Department of Conservation, Division of Mines and Geology, 1997, Seismic Hazard Zone Report for the Anaheim and Newport Beach 7.5 Minute Quadrangle, Orange County, California, Seismic Hazard Zone Report 03. 2. California Department of Conservation, California Geological Survey, State of California, Earthquake Zones of Required Investigation, Newport Beach 7.5 Minute Quadrangle, Earthquake Fault Zones (July 1, 1986), Seismic Hazard Zones, (April 17, 1997 and April 15, 1998), Scale 1:24,000. 3. California Department of Conservation, California Geological Survey, Earthquake Zone App, https://maps.conservation.ca.gov/cgs/EQZApp/, Tsunami Hazard Area Map App, https://maps.conservation.ca.gov/cgs/informationwarehouse/index.html?map=ts_evacu ation. 4. USGS, 2004, Morton, D.M., Bovard, Kelly R., and Alvarez, Rachel M., 2004, Preliminary Digital Geologic Map of the Santa Ana 30’x 60’ Quadrangle, Southern California, version 2.0: U.S. Geological Survey Open-File Report 99-0172. 5. ASCE 7 Hazard Tool, https://asce7hazardtool.online/, February 9, 2023. 6. Blake, Thomas F., 2000, FRISKSP (Version 4.00), EQFAULT and EQSEARCH (Version 3.00), Computer Programs for calculating the site to fault distances, Deterministic peak horizontal ground accelerations for a Maximum Magnitude Earthquake, and historic seismicity for an area from selected known faults in the southern California region (Rev. 2000). 7. USGS Unified Hazard Deaggregation Tool , https://earthquake.usgs.gov/hazards/interactive/#, dated February 3, 2023. 8. International Code Council (ICC), 2022, California Building Code, California Code of Regulations, Title 24, Part 2, Volume 2 of 2. 9. Daniel Martinez Architect, Ocean Blvd. Residence, 2607 Ocean Blvd., Corona Del Mar, CA, Sheets A1.0, A2.0, A3.0, A4.0, A5.0, A6.0, A6.1, A7.0, A7.1, A7.2, and A7.3, dated 03/22/2022. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 17 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com APPENDIX A FIELD INVESTIGATION OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 18 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com HGEI conducted a field investigation of the subject site on January 13, 2023 consisting of drilling, logging and sampling two exploratory borings with a 4-inch-diameter hand auger to a maximum depth of 5.0 feet. The subsurface exploration locations are indicated on Plate A-1a and the logs of the borings are presented on Plates A-2 through A-3. The descriptions represent the prevalent soil types and slightly different material types may be present within the major groupings. Also, the transition from one soil type or condition to another may be gradual rather than abrupt as implied and differing conditions may exist in unexplored areas. Unified Soil Classification System Classification Criteria/Symbols are presented on Plate A-4. A representative of the geotechnical engineer observed the field work, collected samples for transportation to our geotechnical laboratory, and prepared field logs by visual/tactile examination of the materials. Core samples were obtained at discreet intervals using a modified California split-spoon sampler loaded with 2.42” I.D. x 1”-long, thin-wall, brass rings. Bulk samples of the materials were also collected. Samples were placed in plastic bags immediately upon removal from the sampler to conserve moisture and labeled for identification. The borings were backfilled with excavated soils immediately upon completion of sampling. N49°24'40"W 5 5 . 1 5 ' FERNLEAF RAMP PATIO (N) EXISTING NATURAL GRADE TO REMAIN EXISTING BLDG ENV MIDDLE LVLDECK O'HG (N) EXISTING DECK & CATWALKTO BE REMOVED, (DASHED) EXISTING CMU WALL TO REMAIN NEW CONC DRIVE TO SINGLE CAR GARAGE EXISTING BLDG FOOTPRINT NEW CONC DRIVETO (E) 2 CAR GARAGE FLAT ROOF SKY SPA ROOF DECK FLAT ROOF N29°22'52" W 4 9 . 6 6 ' WAY LA N E FL A T R O O F SK Y N5 0 ° 1 1 ' 1 9 " E 5 3 . 3 7 ' D A H L I A A V E N U E N4 0 ° 3 5 ' 1 2 " E 3 5 . 6 1 ' B-1 B-2 Qop Tm N 5 3 E 12 N 8 1 W 22 N 67 W 9 N 2 0 W 11 N 0 2 W 56 N 0 4 W 36 A A' Tm DRAWN BY: SBM CHECKED BY: ALS REVISIONS: DATE: 02/10/2023 Dr a w i n g N a m e : Pr o j e c t : Ad d r e s s : 2 6 0 7 O c e a n B l v d , C o r o n a D e l M a r , C A 9 2 6 2 5 HG E I P r o j e c t N o . : 2 2 - 0 1 - 4 5 0 3 Oc e a n B l v d A d d i t i o n Ge o t e c h n i c a l I n v e s t i g a t i o n GE O T E C H N I C A L M A P \\ H G E I - P C \ E N G I N E E R I N G \ A C T I V E P R O J E C T F I L E S \ 4 5 0 0 \ 4 5 0 3 2 6 0 7 O C E A N B L V D . , C O R O N A D E L M A R , C A \ A U T O C A D \ G E O T E C H N I C A L M A P . D W G Legend Qop Tm Old Paralic Deposits Monterey Formation Bedrock (Circled Where Buried) Approximate Boring Location Approximate Geologic Contact Cross Section Location Bedding Attitudes N Drawing Scale: 1" = 10' Plate A-1a TOPSOIL:SILTY SAND (SM), dark brown, moist, loose, abundant roots, fine to medium grained.BEDROCK (Tm):@ 6" CHERT, white, damp, very hard, heavily folded and undulating, fractured within oxidation, conchoidal fractures MATERIAL DESCRIPTION % Wa t e r C o n t e n t lb / c u f t . Dr y U n i t W e i g h t , Bl o w C o u n t s 0 El e v a t i o n , f e e t De p t h , f e e t Sa m p l e N o . Sa m p l e r G r a p h i c s Sy m b o l / U S C S Re c o v e r y % Project: Job No.: Location: Coordinates: Surface Elev.: Top of Casing Elev.: Drilling Method: Sampling Method: Completion Depth: Date Boring Started: Date Boring Completed: Logged By: Drilling Contractor: Remarks: The stratification lines represent approximateboundaries. The transition may be gradual. OCEAN BLVD, LLC 22-01-4503 2607 Ocean Blvd., Corona Del Mar, CA Grade N/A Hand Auger Rings 0.51/13/231/13/23JBHGEI No groundwater. No caving. PLATE A-2 LOG OF BORING B-1 ngineering, Inc.EchnicaleotGtonarrinH 12 12 106 11518/8" TOPSOIL:SILTY SAND (SM), dark brown, moist, loose, abundant roots, fine to medium grained OLD PARALIC DEPOSITS (Qop):SAND (SP), white/light orange, dry, loose, medium grained, well sorted BEDROCK (Tm): CHERT, white, damp, very hard, heavily folded and undulating, fracturedwith oxidation, conchoidal fractures MATERIAL DESCRIPTION % Wa t e r C o n t e n t lb / c u f t . Dr y U n i t W e i g h t , Bl o w C o u n t s 0 5 El e v a t i o n , f e e t De p t h , f e e t Sa m p l e N o . Sa m p l e r G r a p h i c s Sy m b o l / U S C S Re c o v e r y % Project: Job No.: Location: Coordinates: Surface Elev.: Top of Casing Elev.: Drilling Method: Sampling Method: Completion Depth: Date Boring Started: Date Boring Completed: Logged By: Drilling Contractor: Remarks: The stratification lines represent approximateboundaries. The transition may be gradual. OCEAN BLVD, LLC 22-01-4503 2607 Ocean Blvd., Corona Del Mar, CA Grade N/A Hand Auger Rings 5.01/13/231/13/23JBHGEI No groundwater. No caving. PLATE A-3 LOG OF BORING B-2 ngineering, Inc.EchnicaleotGtonarrinH 1590 NORTH BRIAN STREET, ORANGE, CA. 92867 SOIL CLASSIFICATION CHART USCS CHECKED BY: MVDDRAWN BY: BBC T: (714) 637-3093 F: (714) 637-3096 HGEI Project No.:17-01-3590 PLATE B-9JUNE 22, 2017 OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 19 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com APPENDIX B LABORATORY PROCEDURES & TEST RESULTS OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 20 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com The samples collected during the field investigation were examined and classified by the geotechnical engineer/engineering geologist in the laboratory using the visual/tactile method (ASTM D2487-11 & D2488-17) and selected samples were assigned laboratory testing. Tests were performed in general accordance with latest ASTM standards. The following is a description of the laboratory testing and presents the results which are incorporated in the previous sections of the report. Moisture and Density Determination (ASTM D2216-10 & 7263-09) Field Moisture contents were determined for all samples. The core samples were trimmed and weighed and the dry densities of the material calculated. Moisture and dry density data are presented on the boring logs in Appendix A. Expansion Index Test (ASTM D4829-11) An expansion index test was conducted on a sample considered representative of the site material to establish data on which to base recommendations for design. The test result is presented in Table 1. Water-Soluble Sulfate Test (EPA 300.0) In order to determine the proper cement type for the site, the amount of water-soluble sulfate present in a selected sample of the surface material was determined. The test result is presented in Table 2. Compaction Test (ASTM D1557-12ɛ1) The maximum dry density unit weight and optimum moisture content was established for typical surface/near-surface soil for use in evaluation of existing conditions and initial use during grading. Test results are presented in Table 3. Consolidation Tests (ASTM D2435/D2435 M-11) A consolidation test was performed on an undisturbed sample to determine the magnitude and rate of consolidation of the soil when subjected to incrementally applied controlled-stress loading. A graph of the test results is presented on Plate B-1. Direct Shear (ASTM D3080/D3080 M-11) Direct shear tests were performed on on undisturbed and remolded specimens to determine the static strength of the soil/bedrock. The tests were performed at increased moisture contents and at various confining pressures using a displacement rate of 0.0012 in./min. to establish peak and ultimate strength parameters under adverse conditions of moisture. The shear test results (graphs) are presented on Plates B-2 through B-3. OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 21 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com TABLE 1 Expansion Index Test Results (ASTM D4829-11) Sample Id. Moisture Content (%) Dry Unit Weight (pcf) Calculated Expansion Index Expansion Potential Initial Final Initial Final B-2 @ .5’-5’ 9.9 17.2 109.1 108.9 1 Very Low TABLE 2 Water-Soluble Sulfate Sample ID Water-Soluble Sulfate (%) B-2 @ .5’-5’ 0.0014 TABLE 3 Compaction Test Results (ASTM D1557-12ɛ1) Sample ID Maximum Dry Density, pcf Optimum Moisture Content, % B-2 @ .5’-5’ 121.0 11.0 SAMPLE STORAGE Soil samples presently stored in our laboratory will be discarded 30 days after the date of this report unless this office receives a written request to retain the samples for a longer period. Note that prolonged storage will result in sample degradation and may render them unsuitable for testing. 0-0-0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0100 1,000 10,000 S TRA IN % STRESS, psf CONSOLIDATION TEST 10 15 Specimen Identification Classification DD MC% B-2 2.5 SILTY SAND (SM), (Peak) PROJECT JOB NO. DATE OCEAN BLVD, LLC - 2607 Ocean Blvd., Corona Del Mar, CA 22-01-4503 2/2/23 PLATE B-1ngineering, Inc.EchnicaleotGtonarrinH 0 200 400 600 800 1,000 1,200 1,400 0 500 1,000 1,500 2,000 2,500 S HE AR STR ENG TH ps f NORMAL PRESSURE, psf SHEAR TEST DIAGRAM 106 12 Specimen Identification Classification DD MC% B-2 B-2 0.5 0.5 SAND (SP), (Peak) (Ultimate) PROJECT JOB NO. DATE OCEAN BLVD, LLC - 2607 Ocean Blvd., Corona Del Mar, CA 22-01-4503 2/2/23 PLATE B-2ngineering, Inc.EchnicaleotGtonarrinH 0 200 400 600 800 1,000 1,200 1,400 1,600 0 500 1,000 1,500 2,000 2,500 S HE AR STR ENG TH ps f NORMAL PRESSURE, psf SHEAR TEST DIAGRAM 110 14 Specimen Identification Classification DD MC% B-2 B-2 2.5 2.5 SILTY SAND (SM), (Peak) (Ultimate) PROJECT JOB NO. DATE OCEAN BLVD, LLC - 2607 Ocean Blvd., Corona Del Mar, CA 22-01-4503 2/2/23 PLATE B-3ngineering, Inc.EchnicaleotGtonarrinH OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 22 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com APPENDIX C SEISMIC DATA AND RESPONSE SPECTRUM ASCE 7 Hazards Report Address: 2607 Ocean Blvd Corona Del Mar, California 92625 Standard:ASCE/SEI 7-16 Latitude:33.59747 Risk Category:III Longitude:-117.87825 Soil Class:C - Very Dense Soil and Soft Rock Elevation:64.08 ft (NAVD 88) Page 1 of 3https://asce7hazardtool.online/Thu Feb 09 2023 SS : 1.364 S1 : 0.484 Fa : 1.2 Fv : 1.5 SMS : 1.636 SM1 : 0.725 SDS : 1.091 SD1 : 0.484 TL : 8 PGA : 0.596 PGA M : 0.715 FPGA : 1.2 Ie : 1.25 Cv : 1.173 Seismic Design Category: C - Very Dense Soil and Soft Rock D Design Response Spectrum S (g) vs T(s)a MCE Response SpectrumR S (g) vs T(s)a Design Vertical Response Spectrum S (g) vs T(s)a MCE Vertical Response SpectrumR S (g) vs T(s)a Seismic Site Soil Class: Results: Data Accessed: Thu Feb 09 2023 Date Source: USGS Seismic Design Maps based on ASCE/SEI 7-16 and ASCE/SEI 7-16 Table 1.5-2. Additional data for site-specific ground motion procedures in accordance with ASCE/SEI 7-16 Ch. 21 are available from USGS. Page 2 of 3https://asce7hazardtool.online/Thu Feb 09 2023 The ASCE 7 Hazard Tool is provided for your convenience, for informational purposes only, and is provided “as is” and without warranties of any kind. The location data included herein has been obtained from information developed, produced, and maintained by third party providers; or has been extrapolated from maps incorporated in the ASCE 7 standard. While ASCE has made every effort to use data obtained from reliable sources or methodologies, ASCE does not make any representations or warranties as to the accuracy, completeness, reliability, currency, or quality of any data provided herein. Any third-party links provided by this Tool should not be construed as an endorsement, affiliation, relationship, or sponsorship of such third-party content by or from ASCE. ASCE does not intend, nor should anyone interpret, the results provided by this Tool to replace the sound judgment of a competent professional, having knowledge and experience in the appropriate field(s) of practice, nor to substitute for the standard of care required of such professionals in interpreting and applying the contents of this Tool or the ASCE 7 standard. In using this Tool, you expressly assume all risks associated with your use. Under no circumstances shall ASCE or its officers, directors, employees, members, affiliates, or agents be liable to you or any other person for any direct, indirect, special, incidental, or consequential damages arising from or related to your use of, or reliance on, the Tool or any information obtained therein. To the fullest extent permitted by law, you agree to release and hold harmless ASCE from any and all liability of any nature arising out of or resulting from any use of data provided by the ASCE 7 Hazard Tool. Page 3 of 3https://asce7hazardtool.online/Thu Feb 09 2023 OCEAN BLVD, LLC HGEI Project No: 22-01-4503 February 10, 2023 Page 23 1590 N. Brian Street, Orange, CA 92867-3406 FAX (714) 637-3096 PHONE (714) 637-3093 Please visit our website at www.harringtongeotechnical.com APPENDIX D SLOPE STABILITY ANALYSES