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CUP 91-03C; BP/ARCO FACILITY 5792; UPDATED PRELIMINARY GEOTECHNICAL INVESTIGATION; 2023-04-07
geotechnica/ & forensic engineering Bashar Najar, P.E. NAJARS Engineering Via-email: bashar@najars.com April 7, 2023 1941-A Friendship Drive El Cajon, CA 92020 Tl::."'L (619) 258-9000 www.applied-consultants.com Subject: Updated Preliminary Geotechnical Investigation at the Subject Property Located at 1991 Palomar Airport Rd, Carlsbad, CA, 92011 Dear Mr. Najar: In accordance with your request, we have prepared this preliminary geotechnical investigation report for the subject property located at the aforementioned address. The purpose of this geotechnical investigation was to detennine various parameters of the subsurface soils needed before development of the property can begin. The proposed development is the demolition of an existing carwash building and the construction of a new single-story carwash facility with new paving to accommodate additional parking. Our work consisted of geotechnical observations, subsurface exploration, soil sampling, laboratory testing, calculations and analyses, and the preparation of this report. Location of the site, relative to general topography, streets, and landmarks, is shown on the attached Figure 1. PRELIMINARY GEOTECHNICAL INVESTIGATION CONCLUSIONS After reviewing the results of our preliminary geotechnical investigation, we conclude that there are no significant geoteclmical or geologic constraints that cannot be mitigated by proper planning, design, and the utilization of sound construction practices and in accordance with the recommendations of this report. Consequently, it is our opinion that the development of the site is feasible from a geotechnical standpoint. Remedial grading shall be performed prior to construction of the proposed development and shall consist of removal of existing loose fill soils until competent soils are encountered and the recompaction of the fi11 soils to the required grade. Contact with competent materials is expected within four feet below existing grade. The bottom of excavations shall be approved by a representative of our firm. Upon approval, the upper 6" of the base of excavation shall be scarified, and the fill soils recompacted to equal to or greater than 90% of optimum compaction to the required finish grade. The building pad shall be underlain by a minimum of three feet of recompacted fill. Driveways and parking areas shall be underlain by a minimum of one foot of recompacted fill. 1991 Palomar Airport Rd-Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 1 of36 Localized areas may require deeper removals. Minimally, the removals should extend a lateral distance of at least five feet beyond the limits of settlement sensitive structures and/or the limits of structural fill. If deeper removals are performed, where possible the removals should extend a lateral distance equal to the depth of removal beyond the improvement limits. Removal bottoms should expose competent materials in a firm and unyielding condition. The extent of removals can best be determined in the field during grading when observation and evaluation can be performed by a representative of our firm. The bottoms of the excavations shall be approved by our project geologist, engineer, or technician supervisor prior to placing fills or constructing improvements. If the subsurface materials are detennined to be unsuitable when observed, they shall be removed to below contact with competent material. We appreciate this opportunity to be of service. Should you have any questions, please call our office at (619) 258-9000. Sincerely, I 991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 2 of36 TABLE OF CONTENTS 1.0 SITE DESCRIPTION .......................................................................................................... 4 1.1 PRIOR USAGE / HISTORIC AERIAL PHOTOGRAPHS REVIEW ................................ 4 Fig. 1 Site Location ........................................................................................................................ 7 1.2 SURFACE AND GROUNDWATER .................................................................................. 8 2.0 SITE GEOLOGY ................................................................................................................. 8 2.1 Geologic Literature Review and Field Findings .............................................................. 8 Fig. 2 California Geologic Map .................................................. Error! Bookmark not defined. Fig. 3 Oceanside Geologic Map ................................................... Error! Bookmark not defined. Fig. 4 City of Carlsbad General Plan Geologic and Seismic Hazards ...... Error! Bookmark not defined. 3.0 Geologic and Geotechnical Analysis ................................................................................. 14 3.1 Slope Stability ..................................................................................................................... 14 3.2 Tectonic Setting .............................................................................................................. 14 3.3 Seismic Design Recommendations ................................................................................ 15 3.4 Geologic Hazards ........................................................................................................... 15 3.5 Geotechnical Laboratory Testing ................................................................................... 16 Table 1 : Applied Consultants' Soils Analyses Results ......................................................... 16 4.0 INFILTRATION STUDY .................................................................................................. 17 5.0 CONCLUSIONS ................................................................................................................. 19 5.1 Impact of Geologic Hazards upon Subject Property ...................................................... 19 5.2 Geotechnical Investigation Conclusions ........................................................................ 19 6.0 RECOMMENDATIONS ..................................................................................................... 20 6.1 Grading ........................................................................................................................... 20 6.2 Foundations .................................................................................................................... 22 6.3 Interior Concrete Slabs On-Grade .................................................................................. 22 6.4 Exterior Concrete Flatwork ............................................................................................ 23 6.5 Retaining Walls .............................................................................................................. 23 6.6 Sulfate exposure ............................................................................................................. 24 6. 7 Preliminary Pavement Section Recommendations ......................................................... 25 6.8 Temporary Excavation Slopes ........................................................................................ 25 6.9 Site Drainage .................................................................................................................. 26 FIGURES ...................................................................................................................................... 29 EXPLORATORY BORING LOGS .............................................................................................. 30 GENERAL EARTHWORK AND GRADING ............................................................................ 32 GUIDELINES ............................................................................................................................... 32 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 3 of 36 1.0 SITE DESCRIPTION The location of the property is at latitude 33°07'09"N and longitude 117° 16'54"W. The subject property is located in a commercial district of Carlsbad, California (Figure 1 ). The subject property is bounded to the north by Palomar Airport Road; to the south and west by Palomar Oaks Way; and to the east by Camino Vida Roble. Review of the current topographic map for the site indicates that the subject property is at approximately 177 feet with respect to the North American Vertical Datum of 1988 (NA VD 88) The subject property is a commercial property of approximately 6.8 acres located within assessor's parcel number 213-092-1700. The pad of the property is located at the north and east portions of the property, the pad is bounded to the south and west by variable slopes ranging from 4:1 to 2:1 (run: rise). The property is currently occupied by an existing gas station, a convenience store and a carwash located towards the northern portion of the property. The proposed development is the demolition of an existing carwash building and the construction of a new single-story carwash facility with new paving to accommodate additional parking. 1.1 PRIOR USAGE / HISTORIC AERIAL PHOTOGRAPHS REVIEW i) Historical Aerials As part of our study, we have reviewed historical aerial photographs of the subject property and surrounding area. We noted the following: -Before 1953, the subject property and surrounding area were an undeveloped hillside. -After 1964 but before 1982, Palomar Airport Road had been constructed. The subject property remained undeveloped. -After 1982, the subject property pad had been graded, and Camino Vida Roble had been constructed. -After 1983, a financial bank had been constructed. Palomar Oaks Way had been constructed and the properties to the south of Palomar Oaks Way had been also developed. -After 1992 but before 2009, the financial bank had been demolished and the existing gas station constructed. -After 2009, the existing carwash had been constructed at the southeast portion of the subject property pad. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 4 of 36 ii) Prior Geotechnical Reports and Grading plans We have reviewed the following public documents regarding geotechnical studies and grading activities that took place at the subject property and surrounding areas: • Geotechnical Investigation for Palomar Airport Business Park-Phase II Carlsbad, California, dated September 19, 1977, prepared by Robert Prater Associates o This report detailed the geotechnical exploration performed for the Phase II portion of the Palomar Airport Business Park. o The site plan on Figure 1 of the referenced report indicates that only one exploratory test pit was performed on the subject property (APN 213-092-1700) by a predecessor company to Robert Prater Associates (Lowney/Kaldveer Associates. No discussion or log regarding that test pit was encountered in this report. o According to the exploration from 1977, the materials encountered in the neighboring properties consisted of residual surface soils, colluvial soils and formational sedimentary soils. Formational soils were encountered from 2 feet below ground surface to 6.5 feet below ground surface. o General grading and construction recommendations were provided in this report. • Grading Plan for Carlsbad Tract No. 80-34 Palomar Airport Business Park, AS-BUILT, Drawing# 208-2A, Sheet 2 of 6, dated March 16, 1981, prepared by Herny Worley Associates. o According to this As-built grading plan, a relatively level pad was graded at the north portion of the lot. An approximately 35 feet deep canyon was located at the subject property (APN 213-092-1700). The canyon was filled as part of the grading of subject property lot. The original deepest section of the subject property (APN 213-092-1700) was located at the middle portion of the property. o The pad of the property is followed by a 2:1 fill slope towards the southwest of the pad. o The majority of the north pad lies on documented fill. Shallow fill is located at the northwest and southeast portions of the lot. o The southeast portion of the subject property was cut. o The majority of the south portion of the subject property was left undeveloped. o Drainage of the property was set to sheet flow at a 1 % gradient from north to south. o No compaction reports were found on the City of Carlsbad's online portal regarding the for the grading operations of the referenced grading plan. • Preliminary Subsurface Geotechnical Investigation and Site Characterization, ARCO Station Palomar Airport Rd and Camino Vida Roble, dated January 23, 1991, prepared by Alton Geoscience. o According to this report, five exploratory borings were mechanically augered by Alton Geoscience to a maximum depth of 39 feet below ground surface. One of these borings was augered close to the existing footprint of the carwash to a depth of 20 feet below ground surface. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 5 of 36 o Standard penetration testing was performed at approximately 5-foot intervals. Consistent relatively dense materials were encountered in the exploratory borings, particularly at B-5 that was performed close to the area of the proposed carwash. o Low expansive soils were encountered at the near surface soils of the carwash building pad. o Groundwater was encountered at 39 feet below ground surface in one of the exploratory borings. The boring was augered to the east of the existing islands. o The referenced report recommended removal and recompaction of the upper eighteen inches of the pad, extending at least five feet beyond outside edge of the building footings. • Report of Field Observation and Relative Compaction Test Results, Proposed Arco Station, Palomar Airport Road and Camino Vida Roble, dated September 9, 1992, prepared by Wyman Testing Laboratories. o According to this report, the upper eighteen inches of the gas station and canopy footprint, extending at least five feet horizontally beyond their footprints, was removed and recompacted to at least 90 percent of the maximum dry density prior to construction. • Geotechnical Investigation, ARCO 5792-Carwash Addition, 1991 Palomar Airport Road, Carlsbad, California, dated September 18, 2006, prepared by SECOR International Incorporated. o According to this report, two exploratory borings were mechanically augered by SECOR to a maximum depth of 51.5 feet below ground surface. One of these borings was augered within the existing footprint of the carwash to a depth of 21.5 feet below ground surface. o Standard penetration testing was performed at approximately 5-foot intervals. Consistent relatively medium dense to dense materials were encountered in the exploratory borings, particularly at B-1 that was performed within the area of the proposed carwash. o In-place samples were also collected using a California Modified Sampler. In- place density, moisture and consolidation testing were performed. o Low expansive soils were encountered at the near surface soils of the carwash building pad. o Moderate corrosion potential for concrete and severe corrosion potential for steel was observed in the near surface soils. o Groundwater was encountered at 37.5 feet below ground surface in one of the exploratory borings. The boring was augered to the southeast of the existing convenience store. o The referenced report recommended removal and recompaction to a minimum depth of two feet below the bottom of the building footings, extending at least five feet beyond outside edge of the building footings. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 6 of 36 Geographic Location: -:_-.-.. ',,. l 'APPLIED -••-;1! .. ·1· CONSULTANTS 1991 Palomar Airport Rd, Carlsbad, CA 92011 Site Location Map 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 7 of36 t N Fig. 1 1.2 SURFACE AND GROUNDWATER On January 11, 2022 and April 6, 2023, we performed physical reconnaissance and field work at the subject property. We mechanically excavated six test pits and hand augered two borings as part of our site reconnaissance and obtained samples within the area of the proposed development. We obtained soil samples within the vicinity of the proposed structures. According to the previous grading plans, geotechnical reports and historical aerials, the subject property was a canyon that was filled as part of a mass grading that took place after 1982. The maximum depth of fill throughout the lot is estimated at 35 feet below ground surface. Based upon the AS-BUILT Drawing# 208-2A dated March 16, 1981, and the proposed grading plans by NAJARS Engineering dated March 28, 2023, the proposed carwash and adjacent basins will be underlain by no more than 22 feet of fill soils. The subsurface materials encountered during our investigation were a yellowish brown to yellowish gray poorly graded sand with silt. No groundwater was encountered in the exploratory test pits and borings at the time of our investigation. 2.0 SITE GEOLOGY 2.1 Geologic Literature Review and Field Findings Regional Geology: We reviewed the General Geologic Map of California (Guitierrez, Bryant, Salcedo & Wills, 2010) for references concerning the regional geologic formation underlying the subject property and surrounding areas. Review of the aforementioned geologic map indicates that the underlying geologic formation at the subject property consists of Eocene Marine (E). The Eocene Marine Sedimentary Rocks are commonly defined as: Shale, sandstone, conglomerate, minor limestone; mostly well consolidated. Local Geology: We reviewed the Geologic Map of the San Diego 30' x 60' Quadrangle, California (Kennedy and Tan, 2005) for references concerning the geologic structure underlying the subject property and surrounding areas . Review of the Geologic Map of the Oceanside 30' x 60' Quadrangle indicates that the underlying geologic structure at the subject property consists of the Santiago Formation (Tsa). The Santiago Formation are described as " Named by Woodring and Popenoe (1945) for Eocene deposits of 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 8 of36 northwestern Santa Ana Mountains. There are three distinctive parts. A basal member that consists of buff and brownish-gray, massive, coarse-grained, poorly sorted arkosic sandstone and conglomerate (sandstone generally predominating). In some areas the basal member is overlain by gray and brownish-gray (salt and pepper) central member that consists of soft, medium-grained, moderately well-sorted arkosic sandstone. An upper member consists of gray, coarse-grained arkosic sandstone and grit. Throughout the formation, both vertically and laterally, there exists greenish-brown, massive claystone interbeds, tongues and lenses of often fossiliferous, lagoonal claystone and siltstone. The lower part of the Santiago Formation interfingers with the Delmar Formation and Torrey Sandstone in the Encinitas quadrangle. 2.2 Geotechnical Site Conditions We excavated the following materials in our exploratory test pits and borings: Test pit #1 (T-1): -From grade to four feet below grade a fine to medium grained, loose, yellowish brown poorly graded sand with silt (SP-SM) (Af-Artificial Fill) -From four feet below grade to five feet below grade a fine to medium grained, yellowish/ brownish light gray poorly graded sand with silt (SP-SM) (Tsa -Santiago Formation) Test pit #2 (T-2): -From grade to three feet below grade a fine to medium grained, loose, yellowish brown poorly graded sand with silt (SP-SM) (Af-Artificial Fill) -From three feet below grade to four feet below grade a fine to medium grained, yellowish/ brownish light gray silty sand (SM) (Tsa -Santiago Formation) Test pit #3 (T-3): -Topsoil was encountered from grade to one foot below grade. (Af-Artificial Fill) -From one foot below grade to three feet below grade a fine to medium grained, loose, yellowish brown poorly graded sand with silt (SP-SM)) (Af-Artificial Fill) -From three feet below grade to sixteen feet below grade a fine to medium grained, dense yellowish light gray poorly graded sand with silt (SP-SM) (Tsa -Santiago Formation) Test pit #4 (T-4): -Topsoil was encountered from grade to one foot below grade. (Af-Artificial Fill) -From one foot below grade to four feet below grade a fine to medium grained, yellowish / brownish light gray poorly graded sand with silt (SP-SM) (Af-Artificial Fill) 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 9 of36 Test pit #5 (T-5): -Topsoil was encountered from grade to one foot below grade. (Af-Artificial Fill) -From one foot below grade to four feet below grade a fine to medium grained, yellowish / brownish light gray poorly graded sand with silt (SP-SM (Af-Artificial Fill) Test pit #6 (T-6): -From grade to two feet below grade a fine to medium grained, loose, yellowish brown poorly graded sand with silt (SP-SM) (Af-Artificial Fill) -From two feet below grade to four feet below grade a fine to medium grained, yellowish/ brownish light gray silty sand (SM) (Tsa-Santiago Formation) Hand boring #1 (HB-1): -From grade to two and a half feet below grade a fine to medium grained, yellowish brown poorly graded sand with sitl (SP-SM) (Af-Artificial Fill) Hand boring #2 (HB-2): -From grade to two and a half feet below grade a fine to medium grained, yellowish brown poorly graded sand with sitl (SP-SM) (Af-Artificial Fill) 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 10 of36 ~>-... • ·\ • • p ~ ~ ~ . 1991 Palomar Airport Rd, Carlsbad, CA 92011 Stia!e, ~e. oonglamt!ra!'e, rttnorBmefitOne~ lmfttty "e oon&UJl- ~<1 Regional Geology Geologic Map of California (2010) 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 11 of36 u .... i N Fig. 2 Geographic Location: 1991 Palomar Airport Rd, Carlsbad, CA 92011 j N Santiago Formation (middle Eocene)-Named by Woodring and Popenoe ( l 945) for Eocene deposits of northwestern Santa Ana Mountains. Tl1ere are three distinctive pat1s. A basal member that consists of buff and brownish-gray. massive, coarse-grained, poorly s011ed arkosic sandstone and conglomerate (sandstone generally predominating). In some . . . . . . . . Geologic Map Oceanside Quadrangle 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 12 of 36 Fig. 3 Geographic Location SUBJECT PROPERTY 1991 Palomar Airport Rd, Carlsbad, CA 92011 Potential Liquefaction ~ Riverwash ~ Tidal flats ~ Tujunga sand, 0 to 5 percent slopes ~ Other Hazard Liquefaction Hazards Map City of Carlsbad General Plan Geologic and Seismic Hazards 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 13 of36 i N Fig. 4 3.0 Geologic and Geotechnical Analysis 3. 1 Slope Stability Cross-Section A-A' was prepared to assess the slope stability of the subject site. The location of the cross section is shown on our geotechnical map and represents the most critical slope conditions at the site. Gross stability was evaluated using the computer program GEO5. Our analyses included both rotation and block-glide failure models to generate failure surfaces within the area of the proposed carwash towards the descending slope. The results of our analyses indicate the majority of the slope below the subject site has a minimum factor of safety of 1.5 for static conditions, and greater than 1.1 for seismic calculations. For seismic loading Kh = 0.17 The soil shear strength parameters used in the stability analyses are listed below. These parameters are composite values derived from our current work, and our experience with similar projects in the San Diego County area. These shear values are considered representative of the soils underlying the subject site. Material Description Phi Angle (degrees) Unit Weight Cohesion (psf) Artificial Fill (Documented) 30 111 250 Santiago Formation 31.5 113 150 3.2 Tectonic Setting Southern California, including the City of Carlsbad and surrounding areas, is in an area of late Tertiary to Quaternary-aged fault zones (Kennedy 1975) which strike generally to the northwest. Some of these fault zones are known to be active according to the California Geological Survey. "Active" faults are ones which have had faulting activity within the Holocene Epoch, or the last 11,700 years. The area's most prominent and active faults are those within the Newport- Inglewood-Rose Canyon Fault Zone. Active faults within this fault zone present the most immediate seismic hazards to San Diego and environs. Other Fault zones including the Elsinore fault zone lie in eastern and northern San Diego county. Fault rupture hazard would affect a property if an active fault trace or traces traverse the property. The subject property is not within an Alquist-Priolo Earthquake Fault Zone (Special Studies Zone). The site is about 7.6 miles northeast of faults within the active Newport-Inglewood-Rose Canyon Fault Zone (offshore Oceanside section) with a maximum moment magnitude of 6.9, and 26 miles southwest of the Julian section of the active Elsinore Fault Zone with a maximum moment magnitude of 7 .1. Even though direct ground rupture from faulting directly underneath the subject property is not likely, the property will be subjected to considerable ground acceleration and shaking from an earthquake event along nearby faults. The intensity of ground shaking is dependent on distance from faults, earthquake magnitude and duration, and seismic characteristics of foundation soils and bedrock. According to the USGS Seismic Design Maps based on ASCE/SEI 7-16, the most probable peak ground acceleration for the subject property is 0.438g. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 14 of36 3.3 Seismic Design Recommendations The proposed development shall be designed in accordance with seismic considerations contained in the 2022 California Building Code (2022 CBC), American Society of Civil Engineers (ASCE) Standard 7-16: Minimum Design Loads for Buildings and other Structures and City of Carlsbad requirements. Based on the 2022 CBC and ASCE 7-16, the following parameters may be considered for design: Seismic Importance Factor (I): Occupancy Category: Site Class: Spectral Response Coefficient (Ss) Spectral Response Coefficient (S 1) 3.4 Geologic Hazards 1.0 (ASCE 7-16) II (2022 CBC) D (2022 CBC) 1.001g (ASCE 7 Hazard Tool) 0.364g (ASCE 7 Hazard Tool) The Geologic Map of the Oceanside 30' x 60' Quadrangle, California does not indicate any near landslides or mapped faults under the property. Additionally, no visible evidence of gross earth movement was seen during the site inspection and field work conducted at the subject property. Based on our site inspection and the slope stability analysis performed for the subject property it is our engineering opinion that the potential for failure in landslide and earth movement is low. The City of Carlsbad Geology General Plan -Chapter 6.4: Geologic and Seismic Hazards does not indicate that the subject property is located in a liquefaction area. Liquefaction of cohesionless soils can be caused by strong cyclic accelerations resulting from nearby earthquakes. Research and historical data indicate that loose, granular materials saturated by a near-surface groundwater table are most susceptible to liquefaction. The subsurface materials underlying the subject property do not possess density or saturation characteristics which would make them vulnerable to liquefaction during large seismic events. The potential flooding risk is low provided adequate surface drainage measures are implemented. According to FEMA National Flood Hazard Layer maps, (06073C1033H, 12/20/19), the property is not within a zone at risk by surface water flooding. Minor surficial soil movement due to soil creep and bioturbation is present on virtually all slopes. No visible evidence of gross slope instability was noted during the site inspection and field work conducted at the subject property and surrounding area. The potential landslide risk at the subject property is negligible. No substantial variations in moisture content of the fill soils were noted compared to subsurface explorations from prior years. The in-place samples obtained during our field investigation indicated that the existing fill is at approximately 85% of saturation. Settlement of the existing fill may increase as moisture increases. It is unlikely that the saturation of the fill will substantially increase. However, it is our opinion that a ½ inch of fill settlement shall be considered in addition to the settlement anticipated for the foundation loads. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 15 of 36 Settlement resulting from the anticipated foundation loads should be minimal provided that the recommendations included in this report are considered in design and construction. The total settlement is estimated to be less than one inch when using the recommended bearing pressures. Differential settlement is estimated to be one-half of the total settlement. Provided that our geotechnical recommendations included in this report are followed, it is our professional opinion that the proposed grading and construction will not measurably destabilize nor impact adjacent properties and improvements. 3.5 Geotechnical Laboratory Testing The purpose of collecting relatively undisturbed and bulk soil samples is to determine physical characteristics of subsurface materials through laboratory testing. The soil samples were analyzed for the following: Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates -ASTM C136 Optimum Moisture Content and Maximum Density -ASTM D1557 Direct Normal Shear Resistance Value -ASTM D3080 Expansion Index -ASTM D4829 The following table (Table 1) is a compilation of our soils analyses results from the sample collected within the area of the proposed development. Table 1: Applied Consultants' Soils Analyses Results M.C. Cu Cc uses Dry Relative Optimum Optimum Direct Shear Expansion Density Density Moisture Density Index Sample Phi Cohesion ID (%) (pct) (%) (%) (pct) (angle) (psf) EI HB-1@ 57.48 18.6 --SP-SM 108.35 Medium 14.5 116 30 250 35 (Low) 1.5'-2.5' Dense HB-2@ 47.04 17.5 - -SP-SM 104.17 Medium -- - --1.5'-2.5' Dense T-3@ 12.8 2 1.3 SP-SM - --- - - -15'-16' T-4@ 15.6 3 1.3 SP-SM ---- ---4'-5' T-4@ 18 2 1.0 SP-SM ------4'-5' T-6@ 12.2 SP-SM 112.95 68.01 10 123 32 150 5(Very 3'-4' --Dense Low) pcf -pounds per cubic foot psf -pounds per square foot 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 16 of 36 4.0 INFILTRATION STUDY 4. 1 Site Evaluation As part of our study, we reviewed the State of California, State Water Resources Control Board Geotracker system. There are no active cleanup sites or contaminated sites within a 1000 feet radius of the subject property. There are no "Brown fields" adjacent to the subject property. Groundwater was not encountered during our investigation. Based on our field investigation and the review of available published groundwater data and historical information, groundwater is not expected to be within ten feet below grade of the proposed development. According to the County of San Diego Hydrology Manual -Soil Hydrologic Group. The County of San Diego Hydrology Manual categorizes the soils at the subject property as Hydrologic Group D. The Hydrologic Group D is characterized as "Soils have very slow infiltration rate when thoroughly wetted; chiefly clays that have a high shrink-swell potential, soils that have a high permanent water table, soils that have a claypan or clay layer at or near the surface, or soils that are shallow over nearly impervious material. Rate of water transmission is very slow." 4.2 Infiltration Test Results We performed an Open Pit Falling Head Test at the subject property on January 11, 2022 and January 12, 2022 in conformance with the City of Carlsbad BMP Design Manual. The test pits were excavated to four feet below grade. Test pits #4 and #5 were used to determine the infiltration rate at the subject property. As part of the Design Phase, we performed an "Open Pit Falling Head Test" for measurement of the infiltration rate. The test pits from our planning test was expanded to the dimensions of two feet wide by six feet long. The open Pit Falling Head Test is performed by: "To perform this test, a hole is excavated at least 2 feet wide by 4 feet long (larger is preferred) and to a depth of at least 12 inches. The bottom of the hole should be approximately at the depth of the proposed infiltrating surface of the BMP. The hole is pre-soaked by filling it with water at least a foot above the soil to be tested and leaving it at least 4 hours (or overnight if clays are present). After presoaking, the hole is refilled to a depth of 12 inches and allow it to drain for one hour (2 hours for slower soils), measuring the rate at which the water level drops. The test is then repeated until successive trials yield a result with less than 10 percent change." 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 17 of 36 On January 12, 2022, we performed the Open Pit Falling Head Test in Test pits #4 and #5. The following data was obtained: Time interval (hrs) Test pit 0.0 1.0 2.0 3.0 4.0 5.0 Water 12" 11.0" / 11.75 11.75" 11.5" 11.25" T-4 level 12" @48"b.e.g t.H O" 1.0" 0.25" 0.25" 0.25" 0.25" Refill Water 12" ll"/12" 11.5" / ll"/12" 11.5'' 11' T-5 level 12" @48"b.e.g t.H O" 1.0" 0.5 1.0" 0.5" 0.5" Refill Refill The infiltration rate reached at the end of the tests on both pits was 0.5 in/hr and 0.25 in/hr on T-4 and T-5 respectively. In regards to lateral infiltration, the Porchet Correction was applied for the final hour of infiltration. In a rectangular pit the correction is: / = ilH·Abotto!!:__ ; where: ~H = change in depth (0.5'' and 0.25"); ~t = change in time (1 M·(Abottom +Awall) hr); Abottom: area of the bottom of the pit (2 ft x 6 ft= 12 ft2), and Awall is the average area of the pit's walls, using as a depth the average water depth during the time interval ( 11. 5" and 11. 7 5" / 15.33 ft2 and 15.67 ft2). The corrected average infiltration is: (0.5 in · 12 ft2) / 1hr (12 ft2 + 15.33 ft2) = 0.22 in/hr for T-2 & (0.25 in· 12 ft2) I 1hr (12 ft2 + 15.67 ft2) = 0.11 in/hr for T-6 Corrected average infiltration/ 2 = 0.16 in/hr The design infiltration rate is= corrected average infiltration/ F.S. (Table D.2-3) = 0.16 in/hr/ 3.5 = 0.05 in/hr 4.3 Infiltration Study Conclusions We performed planning phase infiltration testing as part of our study and a design infiltration rate of 0.05 inches/hour was obtained. However, based upon the location of the proposed infiltration BMPs and infiltration restrictions set forth on the City of Carlsbad BMP Design Manual, infiltration of any volume is considered to be restricted within the area of the proposed basins. We recommend that no infiltration be used for this project. If bioretention areas are to be used, all bioretention areas shall have solid concrete bases and/or impermeable liners to prohibit storm water soil infiltration. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page I 8 of 36 5.0 CONCLUSIONS 5. 1 Impact of Geologic Hazards upon Subject Property Based upon our field work and historical research results, we conclude the following: • Ground Shaking is a likely hazard to the site. Seismic activity on any active and potentially active faults will cause ground movement at the subject property that will be proportional to the magnitude and distance of seismic event. Ground movement at the subject property would be moderated by the distance from the epicenter of the seismic event. It is expected that the structure will have to endure this to some degree. • Landslide & Earth Movement. No visible evidence of earth movement was seen during the site inspection and field work conducted at the subject property. While topography and geology of the subject property are susceptible to earth movement, the risk is low for failure in landslide or earth movement. • Liquefaction. The soils characteristics at the subject property are not conducive to failure in liquefaction. It is our professional opinion that the potential for soil liquefaction at the subject site is low. • Flooding. Given the topography of the site and according to FEMA flood hazard maps, flooding is not considered a hazard. 5.2 Geotechnical Investigation Conclusions After reviewing the results of our preliminary geotechnical investigation, we conclude that there are no significant geotechnical or geologic constraints that cannot be mitigated by proper planning, design, and the utilization of sound construction practices and in accordance with the recommendations of this report. Consequently, it is our opinion that the development of the site is feasible from a geotechnical standpoint. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 19 of 36 6.0 RECOMMENDATIONS 6.1 Grading a. General All earthworks shall comply with the grading requirements of the City of Carlsbad except where specifically superseded in this section. Prior to grading a representative of Applied Consultants should be present to discuss the current conditions of the site, grading guidelines and schedule of the earthwork to be completed. b. Grubbing / Clearing Grading should begin with the removal of all structures and improvements as well as all vegetation. These materials should be hauled off the site to a suitable location. c. Site preparation Remedial grading shall be performed prior to construction of the proposed development and shall consist of removal of existing loose fill soils until competent soils are encountered and the recompaction of the fill soils to the required grade. Contact with competent materials is expected within four feet below existing grade. The bottom of excavations shall be approved by a representative of our firm . Upon approval, the upper 6" of the base of excavation shall be scarified, and the fill soils recompacted to equal to or greater than 90% of optimum compaction to the required finish grade. The building pad shall be underlain by a minimum of three feet of recompacted fill. Driveways and parking areas shall be underlain by a minimum of one foot of recompacted fill. Localized areas may require deeper removals. Minimally, the removals should extend a lateral distance of at least five feet beyond the limits of settlement sensitive structures and/or the limits of structural fill. If deeper removals are performed, where possible the removals should extend a lateral distance equal to the depth of removal beyond the improvement limits. Removal bottoms should expose competent materials in a firm and unyielding condition. The extent of removals can best be determined in the field during grading when observation and evaluation can be performed by a representative of our firm. The bottoms of the excavations shall be approved by our project geologist, engineer, or technician supervisor prior to placing fills or constructing improvements. If the subsurface materials are determined to be unsuitable when observed, they shall be removed to below contact with competent material. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 20 of 36 c. Fill Material The materials onsite may be used as compacted fill. If it is necessary to import an engineered fill material. The engineered fill shall be a non-expansive soil and approved by the geotechnical consultant. All fill material must be compacted uniformly to 90% of the maximum dry density (ASTM D1557). Oversized material defined as rock, or other irreducible material, with a maximum dimension of greater than 4 inches, shall not be used as fill material. d. Processing of Fill Areas Prior to placing any new fill soils or constructing any new improvements in areas that have been cleaned out to receive fill, the exposed soils shall be scarified to a depth of six inches, moisture conditioned, and compacted to at least 90 percent relative compaction. In areas to support fill slopes, keys shall be cut into the competent formational material. The base keys shall be at least twelve feet wide and be sloped back into the hillside at least two percent. The keys shall extend at least two feet into the competent materials. No other special ground preparation is anticipated at this time. e. Compaction and Method of Filling All structural fill placed at the site shall be compacted to a relative compaction of at least 90% of its maximum dry density as determined by ASTM Laboratory Test D1557. Fills shall be placed at or slightly above optimum moisture content, in lifts six inches thick, with each lift compacted by mechanical means. Fills shall consist of approved earth material, free of trash or debris, roots, vegetation, or other materials determined to be unsuitable by our soil technicians or project geologist. Fill material shall be free of rocks or lumps of soil in excess of 4 inches in maximum dimension. Utility trenches backfill within five feet of the proposed structures and beneath all pavements and concrete flatwork shall be compacted to a minimum of 90 percent of its maximum dry density The upper twelve inches of subgrade beneath paved areas shall be compacted to 95 percent of the material's maximum dry density. This compaction shall be obtained by the paving just prior to placing the aggregate base material and shall not be part of the mass grading requirements or operation. f. Grading Observation It is necessary for a soils engineer, or their representative, to be present and test the compaction during the basic grading operations and placement of fill material. The engineer will be able to confirm the conditions stated in this report and verify that the grading operations are in compliance with all plans and specifications. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 21 of36 6.2 Foundations a. General Where foundations are to be located ten feet and further away from the top of slopes, standard design may take place in conformance with the recommended soil bearing value. In situations where foundations, footings, walls, etcetera, are located closer than ten feet from the top of slope they shall be deepened so that the bottom edge of the footing is seven feet horizontally from daylight in the slope. b. Minimum dimensions Minimum width Minimum depth* (inches) (inches) 1-story structure 15 18 * Depth below the lowest grade. Embedment into competent soils. **Foundation reinforcement shall be designed by the structural engineer. Minimum 3" of concrete coverage for steel reinforcement. c. Bearing Capacity An allowable soil bearing capacity of 1,500 pounds per square foot may be used in the design of these foundations. 6.3 Interior Concrete Slabs On-Grade a. Floor Slab If any new interior floor slabs are used for this project, they should be no less than 4" in thickness (actual). For one-story or greater structures slab reinforcement should consist of #3 rebar placed at 18" on center. All slab reinforcement should rest on concrete chairs or a suitable substitute. b. Moisture Protection The areas covered by the interior floor slab should be covered with a 10 mil Visqueen moisture barrier. The moisture barrier should rest on two inches of sand and be overlain by two inches of clean sand. 1991 Palomar Airport Rd - U p d a t e d Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 22 of 36 6.4 Exterior Concrete Flatwork Concrete flatwork shall be a minimum of 4 inches thick and be reinforced with a minimum of #3 rebar spaced at no more than 18 inches on center. Thickened edges shall be provided adjacent to perimeter slabs and landscape areas and shall be a minimum of 8 inches thick. Controls joints shall be constructed at no more than 10 feet apart in both directions. For sidewalks, control joints shall be provided spaced at no more 6 feet. The control joints shall be sawed, grooved or formed and shall be extended into the slab to a depth of one fourth of the slab thickness. 6.5 Retaining Walls a. General Where foundations are to be located seven feet and further away from the top of slopes, standard design may take place in conformance with the recommended soil bearing value. In situations where foundations, footings, walls, etcetera, are located closer than seven feet from the top of slope they shall be deepened so that the bottom edge of the footing is 7 feet horizontally from daylight in the slope. The retaining wall foundations shall be embedded to a minimum of eighteen inches into competent native soils or into recompacted soils to greater than 90% of optimum compaction. b. Design Parameters The following values shall be used for the design of the earth retaining structures for the subject property: Equivalent Fluid Pressure Level Backfill 2: 1 Sloping Backfill Active Pressure 45 pcf 65 pcf At-rest Pressure* 65 pcf 85 pcf Passive Pressure 350 pcf 350 pcf (Level toe) Passive Pressure 150 pcf 150 pcf (2:1 Descending Slope) -Unit weight of soil = 126 pcf -Kh = 0.17, Seismic loading (For walls retaining more than 6 feet) -Strength Level Seismic force factor (Fp/Wp) = 0.2 -Coefficient of friction of soil to concrete = 0.35 -Allowable Bearing Pressure= 1,500 psf 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 23 of 36 * The retaining wall sections adjacent to retaining wall comers shall be designed to withstand At-rest pressures for an equivalent horizontal distance of H (height of wall) ** The structural designer shall consider surcharge loads from adjacent structures or vehicular loads into the retaining wall design where applicable. c. Retaining Wall Subsurface Drainage All retaining walls shall have a subsurface drainage system behind them to prevent buildup of hydrostatic pressures. Conventional concrete or CMU retaining walls shall be backfilled with clean sand and gravel. The immediate twelve inches behind the retaining walls shall be backfilled with¾" gravel protected with filter fabric. A minimum 4" perforated Schedule 40 PVC or ABS drainpipe shall be installed at bottom of wall. The drainpipe shall positively slope where water can be removed by pumping or gravity. Backfill beyond the gravel drain should consist of clean granular material compacted to greater than 90% of relative compaction. While all backfills should be compacted to the required compaction, extra care should be taken when working close to walls to prevent excessive pressure buildup. Prefabricated drainage composites such as Miradrain 6200, or equivalent, shall be used for shotcrete retaining walls constructed against temporary shoring. d. Allowable horizontal deflection Retaining walls designed with the recommended parameters included in this report are expected to have a maximum horizontal deflection of 1 % of the retained height. 6.6 Sulfate exposure No testing for soluble sulfate concentrations had been performed by our company for the subject property soils. However, previous reports indicated that moderate corrosion potential for concrete and severe corrosion potential for steel was observed in the near surface soils. The concrete used for the proposed development shall consist of Type V, HS cement with a Minimum Design Compressive Strength re = 4,500psi and a Maximum Water- Cementitious material ratio by mass of 0.45. We recommend that a competent corrosion expert be retained to evaluate the corrosion potential of the site for the proposed improvements, to recommend further testing as required, and to provide specific corrosion mitigation methods for the appropriate project. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 24 of 36 6. 7 Preliminary Pavement Section Recommendations Based on the R-value test results and the referenced traffic indexes, the following preliminary pavement section was obtained in conformance with Caltrans Standard Flexible Pavement Design, Modified Portland Cement Association (PCA) Design and the County of San Diego Public Work Standards: Asphalt Pavement Portland Cement Sample R-Value Traffic Index Concrete Pavement Section Section 5.0 4.0" AC over 8.0" 6.5" PPC over 2" T-2 @0'-1' 21 (Parking/ Class 2 Aggregate Class 2 Aggregate Dispensing stations) Base Base 8.5 6.0" AC over 10.0" 8" PPC over 2" Class T-2 @0'-1' 21 (Drive Aisle -Class 2 Aggregate 2 Aggregate Base Tanker Trucks) Base The upper 12 inches of the subgrade soils and the aggregate base shall be compacted to a minimum of 95 percent relative compaction (ASTM D1557) and shall be in conformance with the Standard Specifications for Public Works Construction. The concrete pavement shall consist of 560-C-3250 concrete with a minimum module of rupture (MOR) of 600. Saw-cut weakened-plane joints shall be provided at about 15-foot on center both ways and at re-entrant comers. The placement slabs should be saw-cut as soon as practical, but no more than 24 hours after the placement of the concrete. The depth of the joint should be ¼ of the pavement thickness and its width should not exceed 0.02- feet. Reinforcing steel is not necessary unless it is desired to increase the joint spacing recommended above. Control and isolation joints shall be sealed with elastomeric joint seal. Prior to commencement of the pavement works, additional R-value tests shall be performed on the soils that will underlie the new pavement sections for geotechnical consultant's approval. 6.8 Temporary Excavation Slopes Temporary excavation slopes in the existing subsurface soils and or bedrock may be made vertical for cuts less than four (4) feet and where no existing structures are located within seven feet or within the 45-degree zone of influence pressure from adjacent structures. Additionally, a combination of a 1 :1 cut slope with vertical cut less than 4' is acceptable; provided that the given condition is inspected immediately by the geotechnical engineer of record to verify that the soils present verify our logs. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 25 of 36 For deeper cuts, temporary excavation slopes shall be made no steeper than 1: 1 (horizontal to vertical). In areas where soils with little or no binder ( cohesion) are encountered, shoring or flatter excavation slopes shall be made. Attention is directed to the fact that while cavmg was not encountered in the test excavations, it is possible that a trench or excavation could react in an altogether different manner. All excavations shall be made in accordance with the governing regulations of the State of California Division of Industrial Safety. These recommended temporary slopes do not preclude local raveling and sloughing. If temporary excavation slopes do not comply with the above, a temporary shoring system shall be designed and installed to withstand surcharge from adjacent structures in addition to the active and passive pressures generated by the vertical cut. 6.9 Site Drainage (a) Surface grades adjacent to buildings should be designed and constructed to direct and facilitate drainage away from structures to approved drainage facilities. Recommended minimum grade in unpaved soil areas around buildings and asphalt- paved areas is 5 percent, and in concrete paved areas is 2 percent. Accumulation of water around buildings should be avoided. Concentrations of surface run-off should be collected and drained to suitable discharge outlets. (b) Approved drainage patterns should be installed and maintained throughout the life of structures. The building and surface drainage facilities should not be altered without the prior review and approval of the Project Civil Engineer. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 26 of 36 7.0 REVIEW, OBSERVATIONS, AND TESTING (a) The final foundation/grading plans should be provided to our office for review in order to evaluate the acceptability of the recommendations presented herein, and provide additional recommendations, as appropriate. (b) All construction activities during grading and foundation excavations should be continuously monitored and observed by the Geotechnical Engineer, Engineering Geologist of Record, or their representative. ( c) All grading and foundation excavations on-site should be observed and tested as required, by a representative of the Geotechnical Engineer and or Engineering Geologist to verify conformance with the intent of the geotechnical/geological recommendations provided herein and to evaluate the acceptability of these recommendations for the actual site conditions. CONSTRUCTION INSPECTION AND LIMITATIONS The recommendations contained within this report are based upon our field investigation. The interpolated subsurface conditions should be checked during construction by a representative of Applied Consultants. We recommend that all grading operations be observed by a representative of this firm. The recommendations contained within this report are based upon our field study, laboratory analyses, and our understanding of the proposed construction. If any soil conditions are encountered differing from those assumed in this report, we should be immediately notified so that we can review the situation and make supplementary recommendations. Additionally, if the scope of proposed work changes from that described in this report, we should be notified. This report has been prepared in accordance with generally accepted soil and foundation engineering practices within the greater San Diego area. Professional judgments contained herein are based upon our evaluation of the technical information gathered, our understanding of the proposed work, and our general experience in the geotechnical field. Our engineering work and judgments rendered meet current professional standards. We do not guarantee the performance of the project in any respect. We do not direct the contractor's operations and we cannot be responsible for the safety of field personnel on the site; therefore, the safety of field personnel during construction is the responsibility of the contractor. The contractor shall notify the owner if he considers any of the recommended actions contained herein to be unsafe. It is a pleasure to be of service to you. Should any questions arise, please contact our office at 619- 258 -9000. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 27 of 36 REFERENCES 1. American Society of Civil Engineers/Structural Engineering Institute (ASCE/SEI) Standard 7-16. 2. Bearing Capacity for Shallow Foundations -T. William Lambe & Robert V. Whitman, "Soil Mechanics", John Wiley & Sons, 1969. 3. California Building Code (CBC 2022), 2022 4. California Mines and Geology Division (DMG), 1974, "Maximum Credible Rock Acceleration From Earthquakes in California", Roger W. Greensfelder. 5. California Department of Conservation, Division of Mines and Geology (CDMG), 1987. "CSMIP Strong-Motion Records from the Whittier, California Earthquake of 1 October, 1987", OMS Report 87-05. 6. Federal Emergency Management Agency, 2019. National Flood Hazard Layer viewer. 7. Geology of the Oceanside 30' x 60', California Division of Mines and Geology, Michael P. Kennedy and Siang S. Tan, 2007. 8. 2008 USGS National Seismic Hazards Maps -Fault parameters http://earthquake.usgs.gov/hazards/ 9. USGS Seismic Design Maps for Engineers -Buildings Pre 2009 -Java Ground Motion Parameter Calculator http://earthquake.usgs.gov/hazards/designmaps/javacalc.php 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 28 of 36 FIGURES 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 29 of 36 / LEGEND: Af-Artificial Fill (Documented) Tsa -Santiago Formation \ T-1 EXPLORATORY TEST PITS/ ~ BORINGS LOCATION \ ' -----·-_-:_.7 ---·- REFERENCE: This figure was prepared from the AS-BUILT, Drawing # 208-2A by Herny Worley Associates and from the field investigation performed by APPLIED CONSULTANTS. -APPLIED CONSULTANTS FIGURE A: GEOLOGIC/GEOTECHNICAL MAP (ORIGINAL PAD;\ 1991 PALOMAR AIRPORT RD " Date : 4/7 /23 Drawn by: JL VG .,,.,._,,__pology ........... CARLSBAD, CALIFORNIA 9201 1 1 ~ SCALE: 1 "= 100' LEGEND: Af -Artificial Fill (Documented) Tsa -Santiago Formation T-1 EXPLORATORY TEST PITS/ \ BORINGS LOCATION . -..... ,. APPROXIMATE LIMITS OF REMEDIAL GRADING ·-·-I .... ............... , --..., __ /- S:. •::.,1 ,.;'.; ~. \': , ,.;,-i.-; -::-.. ...:,.., -::~,.r - --. PALOMAR OAKS WAY -----·--- REFERENCE:_THIS MAP WAS PREPARED FROM A GRADING PLAN PREPARED BY NAJARS ENGINEERING FROM THE FIELD INVESTIGATION PERFORMED BY APPLIED CONSULTANTS. -APPLlED CONSULTANTS FIGURE A: GEOLOGIC/GEOTECHNICAL MAP (EXISTING) Date : 4/7 /23 Drawn by: JL VG _....,.,,_........, . ...,,...... 1991 PALOMAR AIRPORT RD, CARLSBAD, CALIFORNIA 92011 SCALE: 1 "= 100' A' PROPOSED BASIN (E) GRADE HB-2 -------- ---PROPOSED ------CARWASH ~ Af ------ REMEDIAL GRADING PER GEOTECHNICAL REPORT ------------ A --- 215-- 210-- 205-- 200-- 195-- 190-- 185-- 180-- 175-- 170-- 165-- 160-- 155-- - ----------~ GRADE PRIOR TO MASS GRADING PER Drawing # 208-2A ----- ? REFERENCE: This Figure was prepared from a grading plan prepared by NAJARS Engineering from the field investigation performed by applied consultants. -APPLIED CONSULTANTS fllWlron,,,,.,,tol ~ 4-w,g!,-ing ------------------? ---------- ? SCALE: HORIZ. 1" = 1 0' VERT. 1" = 10' --------- ? FIGURE C: GEOLOGIC CROSS SECTION A-A' 1991 PALOMAR AIRPORT RD, CARLSBAD, CALIFORNIA 92011 ? LEGEND: EXISTING GRADE Af ARTIFICIAL FILL (DOCUMENTED) Tsa SANTIAGO FORMATION [·'••-.·,] PROPOSED ENGINEERED FILL Date : 4/7 /23 Drawn by : JLVG ASCE. M1911CAN SIICIETYOf CVI. ENGINl!IIS Address: 1991 Palomar Airport Rd Carlsbad, California 92011 https://asce 7hazardtool .online/ ASCE 7 Hazards Report Standard: ASCE/SEI 7-16 Risk Category: Ill Soil Class: D -Stiff Soil Page 1 of 4 Elevation: 177.82 ft (NAVO 88) Latitude: 33.1 1905 Longitude: -117.281939 Thu Jan 13 2022 ASCE. AMIRICAN SOCIETY IJ CML ENGINEERS Seismic Site Soil Class: D -Stiff Soil Results: Ss : 1.001 So1 : N/A S1 0.364 TL : 8 Fa : 1.1 PGA : 0.438 Fv : N/A PGA M: 0.509 SMs 1.101 FPGA 1.162 SM1 N/A 18 : 1.25 Sos 0.734 Cv : 1.3 Ground motion hazard analysis may be required. See ASCE/SEI 7-16 Section 11.4.8. Data Accessed: Thu Jan 13 2022 Date Source: usGs Sejsmjc Design Maps https://asce7hazardtool .online/ Page 2 of 4 Thu Jan 13 2022 ASCE. AMERICAN SOCIElY OF a.'11. EIIGINEBIS Flood Results: Flood Zone Categorization: X (unshaded) Base Flood Elevation: Data Source: Date Accessed: FIRM Panel: Insurance Study Note: https://asce7hazardtool.online/ FEMA National Flood Hazard Layer -Effective Flood Hazard Layer for US, where modernized /https://msc.fema.qov/portal/search} Thu Jan 13 2022 If available, download FIRM panel here Download FEMA Flood Insurance Study for this area ~ Page 3 of4 Thu Jan 13 2022 ASCE. AMERICAN SOCIETY OF CM. ENW,IE!llS 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. VVhile 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. https://asce7hazardtool.online/ Page4 of4 Thu Jan 13 2022 Appendix D: Geotechnical Engineer Analysis . C This section is only applicable if the analysis of infiltration restrictions is performed by a licensed engineer practicing in geotechnical engineering. The SWQ.MP Preparer and Geotechnical Engineer must work collaboratively to identify any infiltration restrictions identified in Table D.1-1 below. Upon completion of this section, the Geotechnical Engineer must characterize each DMA as Restricted or Unrestricted for infiltration and provide adequate support/discussion in the geotechnical report. A DMA is considered restricted when one or more restrictions exist which cannot be reg,sonably resolved through site design changes. Table D.1-1: Considerations for Geotechnical Analysis of Infiltration Restrictions BMP is within 100' of Industml Activities Lack.iog Source Control BMP is within 100' of Well/Groundwater Basin BMP is within 50' of tic Tanks/Leach Fields BMP is within 10' ofSttuctures/Tanks/Walls BMP is within 10' of Sewer Utilities BMP is within 1 o• of Groundwater Table BMP is within Hydric Soils BMP is within Highly liquefu.ble Soils and has Connectivity to Structures BMP is within 1.5 Times the Height of Adjacent Steep Slopes P-25%) County Staff has Assigned ''Restricted" In.filtration Category BMP is within Predominantly Type D Soil BMP is within 10' of Property Line BMP is within Fill Depths of 2!5' (Existing or Proposed) BMP is within 10' of Underground Utilities BMP is within 250' of Ephancral Stte2tn Other (Provide detailed gcotechnical support) Based on examination of the best available information, □ I have,not identified any restrictions above. Unrestricted. Based on examination of the best available infonnation, I have identified one or more restrictions above. Restricted Table D.1-1 is divided into Mandatory Considerations and Optional Considerations. Mandatory D-1 Sept. 2021 Appendix D: Geotechnical Engineer Analysis Considerations include clements that may pose a significant risk to human health and safety and must always be evaluated. Optional Considerations include elements that are not necessarily associated with human health and safety, so analysis is not mandated through this guidance document. All clements presented in this table are subject to the discretion of the Geotechnical Engineer if adequate supporting infonnation is provided. Applicants must evaluate infiltration restrictions through use of the best available data. A list of resources available for evaluation is provided in Section B.2 D.2 ( This section is otll.y applicable if the determination of design infiltration rates is performed by a licensed engineer practicing in geotechnical engineering. The guidance in this section identifies methods for identifying observed infiltration rates, corrected infiltration rates, safety factors, and design infiltration rates for use in structural BMP design. Upon completion of this section, the Geotechnical Engineer must recommend a design infiltration rate for each DMA and provide adequate support/ discussion in the geotechnical report. Table D.2-1: Elements for Detetmination of Design Infiltration Rates Item Value l :nit Initial Infiltration Rate o.?,1S Identify per Section D.2.1 in/ht Corrected Infiltration Rate Identify per Section D.2.2 0 . \b in/hr Safety Factor ~-S unitlcss Identify per Section D.23 Design Infiltration Rate o.os in/hr Corrected Infiltration Rate + Safety Factor D-2 Sept. 2021 Consideration Suitability Assessment (A) Design (B) Appendix D: Geotechnical Engineer Analysis Table D.2-3: Detetmination of Safety Factor Assigned Factor Product (p) Weight (w) Value (v) p =wxv Infiltration Testing Method 0.25 O,t; O Soil Texture Class 0.25 Refer to 0 ,:/-~ Soil Variability 0.25 TableD.2-4 (),'2~ Depth to G1:oundwater/Obsttuction 0.25 D, 2..5 Suitability Assessment Safety F2ctor, SA = I:p \ .1-s Pretreatment 0.50 l Resiliency 0.25 Refer to 0,SO TableD.2-4 Compaction 0.25 o.~ Design Safety Factor, SB = l:p 2 ,e () Safety Factor, S = SA x Sa ~-5 (Must be always greater trum or equal to 2) The geotechnical engineer should reference Table D.2-4 below in order to determine appropriate factor values for use in the table above. The values in the table below are subjective in nature and the gcotcchnical engineer may use professional discretion in how the points arc assigned. D-12 Sept. 2021 EXPLORATORY TEST PITS/ BORING LOGS 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 30 of 36 Project Name: PALOMAR AIRPORT ROAD CAR WASH Date: 1/11/2022 Address: 1991 PALOMAR AIRPORT RD Logged By: JLVG CARLSBAD2 CA Reviewed By: BJL Location: NW OF PROPOSED CARWASH (EL. 204} Footing Thickness (in.): Excavation Method: BACKHOE Depth to Water (ft): NA TestPit/TestBoringlD: T-1 Sa;{1JleT~: BULK Caving: NONE To Der ft): 5.0 Denth ofFootine:: hlA Depth Sample Discrete Bulk Lithology & Footing (FT) Soil Description Sample Sample Details i' rrype ID MC% Interval Interva ~ !Grade 1 -1 --Poorly graded sand w/ Silt (SP-SM): - 2 -fine to medium grained, loose, Artificial Fill 2- yellowish brown poorly graded sand -with silt. (Docwnented) - 3 -3 --- 4 ,_ Transition to denser material 4-SP-SM): fine to medium grained, T-1 ~ -yellowish brownish light gray SP-SM 4'-5' Tsa -Santiago Formation - 5 5 --END OF TEST PIT@ 5 FT - 6 -6- ,_ - 7 -7--- 8 -8- ,_ - 9 -9_ -- IO ,_ 10- ,_ - 11 -11--- 12 -12- ,_ - 13 -13--- 14 -14- ,_ - 15 ,_ 15--- 16 -16- ,_ - 17 ,_ 17- ,_ - 18 -18- ,_ - 19 -19- -APPLIED TEST PIT LOG: T-1 DATE: 1/11/2022 1991 PALOMAR AIRPORT RD Drawn By: JLVG CONSULTANTS CARLSBAD, CA ~ ..... .-~ Project Name: PALO MAR AIRPORT ROAD CARWASH Date: 1/11/2022 Address: 1991 PALOMAR AIRPORT RD Logged By: JLVG CARLSBAD. CA Reviewed By: ~TT Location: SW OF PROPOSED CARWASH (EL. 204) Footing Thickness (in.): Excavation Method· BACKHOE Depth to Water (ft): NA Test Pit/Test Boring ID: T-2 S81:leT~: BULK Caving: NONE To Den ft): 4.0 Denth of F ootin~: NA Depth Sample Discrete Bulk Lithology & Footing (FT) Soil Description Sample Sample Details i' Type II) ID MC% Interval Interval b Grade Poorly S!]ded sand w/ Silt {SP-SM): 1 -fine to medium grained, loose, 1 --yellowish brown poorly graded sand Artificial Fill - 2 -with silt. (Documented) 2- -- 3 -Transition to denser material - ---- -3 -SP-SM): fine to mediwn grained, T-2 ~ -yellowish brownish light gray SP-SM 3'-4' Tsa -Santiago Formation - 4 4- ..___ END OF TEST PIT@ 4 FT - 5 ..___ 5- ..___ - 6 -6--- 7 ..___ 7--- 8 -8--- 9 -9_ -- 10 -10--- 11 -11--- 12 -12--- 13 ..___ 13--- 14 -14- ----- 15 ----15--- 16 -16- -- 17 -17- -- 18 -18- -- 19 -19- -APPLIED TEST PIT LOG: T-2 DATE: 1/11/2022 1991 PALOMARAIRPORTRD Drawn By: JL VG CONSULTANTS CARLSBAD, CA --·- Project Name: PALOMAR AIRPORT ROAD CARWASH Date: 1/11/2022 Address: 1991 PALOMARAIRPORTRD Logged By: JLVG CARLSBAD2 CA Reviewed By: BJL Location: WEST OF PROPOSED BASIN (EL. 198) Footing Thickness (in.): Excavation Method: BACKHOE Depth to Water (ft): NA Test Pit/Test Boring ID: T-3 S~leT~: BULK Caving: NQNE To Deti ft): 16 Depth ofFootiw?;: NA Depth Sample Discrete Bulle Lithology & Footing (FT) Soil Description Sample Sample Details i Type ID MC% Interval Interval !::, Grade ITOJ2SOil 1 -1 -Poorli graded sand w/ Silt (SP-SM): Artificial Fill --fine to medium grained, loose, 2 -yellowish brown poorly graded sand (Documented) 2- T-3 ~ -with silt. 2'-3' -Transition to denser material 3 -- - - -3--- 4 -4--- 5 -5--- 6 -Poorly W<Uled sand w/ Silt 6--(SP-SM): fine to medium grained, - 7 -dense, yellowish light gray poorly Tsa -Santiago Formation 7-graded sand with silt. -- 8 -8--- 9 -Tsa -Santiago Formation 9_ -- 10 -10--- 11 -11--- 12 -12--- 13 -13--- 14 -14--- 15 -15- T-3 12.8 ~ --15'-16' 16 16--END OF TEST PlT@ 16 FT - 17 -17--- 18 -18--- 19 -19- -APPIJED TEST PIT LOG: T-3 DATE: 1/11/2022 1991 PALOMAR AIRPORT RD Drawn By: JL VG CONSULTANTS CARLSBAD, CA ...,__.,...., .. ......., Project Name: PALOMAR AIRPORT ROAD CARWASH Date: 1/11/2022 Address: 1991 PALOMAR AIRPORT RD Logged By: JLVG CARLSBAD1 CA Reviewed By: RTT Location: SOUTH OF PROPOSED BASIN {EL. 199) Footing Thickness (in.): Excavation Method: BACK.HOE Depth to Water (ft): NA Test Pit/Test Boring ID: T-4 S~leT~e: BULK Caving: NONE To Dep (ft): 4 Depth of Footing: NA Depth Sample Discrete Bulle Lithology & Footing (FT) Soil Description Sample ".C' Sample Details Cl) Type ID Cl) MC% Interval Interval !=, Grade Toosoil l ,__ 1 - ,__ - 2 -Poorl:i ~ded sand w/ Silt 2-{SP-SM): fine to medium grained, Artificial Fill -loose, yellowish brown poorly (Documented) - 3 -graded sand with silt. 3- T-4 ~ ,__ 3'-4' 15.6 - 4 4--END OF TEST PIT@ 4 FT - 5 ,__ 5- ,__ - 6 -6--- 7 I-7--- 8 -8--- 9 ,__ 9_ -- 10 -10--- 11 -11--- 12 -12- -- 13 -13- -- 14 -14- -- 15 -15 --- 16 I--16- I--- 17 -17- I--- 18 -18- I--- 19 -19- -APPIJED TEST PIT LOG: T-4 DATE: 1/11/2022 1991 PALOMAR AIRPORT RD Drawn By: JL VG CONSULTANTS CARLSBAD, CA __ ._,,, Project Name: PALOMAR AIRPORT ROAD CARWASH Date: 1/11/2022 Address: 1991 PALOMAR AIRPORT RD Logged By: JLVG CARLSBAD2 CA Reviewed By: BJL Location: SOUTH OF PROPOSED BASIN (EL. 200} Footing Thickness (in.): Excavation Method· BACKHOE Depth to Water (ft): l\fA Test Pit/Test Boring ID: T-5 S~leT~: BULK Caving: NONE To Der ft): 4 Deoth of Footing: N:8 Depth Sample Discrete Bulle Lithology & Footing (FT) Soil Description Sample Sample Details j Type ID MC% Interval Interval f:!, Grade Tonsoil 1 -1 --- 2 -Poorly graded sand w/ Silt 2-(SP-SM): fine to medium grained, Artificial Fill -yellowish brownish light gray (Documented) - 3 -poorly graded sand with silt. 3 -T-5 ~ -3'-4' 18 - 4 4--END OF TEST PIT@ 4 FT - 5 -5--- 6 -6 --- 7 -7 --- 8 -8--- 9 -9_ -- 10 --10--- 11 -11--- 12 --12--- 13 -13- ,-- 14 -14--- 15 -15--- 16 -16--- 17 -17--- 18 -18--- 19 -19- -APPLIED TEST PIT LOG: T-5 DATE: 1/1 1/2022 1991 PALOMAR AIRPORT RD Drawn By: JL VG CONSULTANTS CARLSBAD, CA --·- Project Name: PALOMAR AIRPORT ROAD CAR WASH Date: 1/11/2022 Address: 1991 PALOMARAIRPORTRD Logged By: JLVG CARLSBAD1 CA Reviewed By: ~ rr Location: EAST OF PROPOSED CARWASH (EL. 205) Footing Thickness (in.): Excavation Method· BACKHOE Depth to Water (ft): NA Test Pit/fest Boring ID: T-6 S~le~e: DISCRETE/ BULK Caving: NONE To De (ft): 4 Denth of Footing: NA Depth Sample Discrete Bulle Lithology & Footing (FT) Soil Description Sample c-Sample Details 0 Type ID 0 MC% Interval Interval E=, Grade 1 -Poorly graded sand w/ Silt {SP-SM): Artificial Fill 1--fine to medium grained, loose, (Documented) -yellowish brown SP-SM 2 -2--Poorly graded sand w/ Silt {SP-SM): - 3 -fine to medium grained, yellowish 3- brownish light gray SP-SM T-6 12.2 ~ ~ Tsa -Santiago Formation --3'-4' 4 4--END OF TEST PIT@ 4 FT yd=l 12.95 pcf - 5 -Dr=68.01% 5--Dense - 6 -6--- 7 -7--- 8 -8--- 9 -9_ -- 10 -10--- 11 -11--- 12 -12--- 13 -13--- 14 -14--- 15 -15--- 16 -16--- 17 -17--- 18 -18--- 19 -19- -APPLlED TEST PIT LOG: T-6 DATE: 1/11/2022 1991 PALOMAR AIRPORT RD Drawn By: JLVG CONSULTANTS CARLSBAD, CA ......,...,....,,.~ Project Name: PALO MAR AIRPORT ROAD CAR WASH Date: 4/6/2023 Address: 1991 PALOMAR AIRPORT RD Logged By: JLVG CARLSBAD2 CA Reviewed By: JED Location: DESCENDING SLOPE (EL. 197} Footing Thickness (in.): Excavation Method: HAND AUGER Depth to Water (ft): NA Test Pit/fest Boring ID: HB-1 sa:yle ~: DISCRETE/ BULK Caving: NONE To De ft): 1 Deoth of Footing: NA Depth Sample Discrete Bulk Lithology & Footing (FT) Soil Description Sample Sample Details i' Type ID G) MC% Interval Interval ft, Grade 1 -Poorly w.uled sand w/ Silt (SP-SM): Artificial Fill 1--fine to medium grained, medium (Documented) - 2 1--dense, yellowish brown poorly ---2- graded sand with silt. HB-1 18.6 ~ ~ Tsa -Santiago Formation -2'-3' - 3 3--END OF BORING@ 3 FT yd=108.35 pcf - 4 1--Dr=57.48% 4--Medium Dense - 5 -5--- 6 -6 - 1--- 7 -7--- 8 -8- 1--- 9 -9_ -- 10 1--10--- 11 -11- -- 12 -12- -- 13 -13- -- 14 -14- -- 15 -15- -- 16 -16- -- 17 -17- -- 18 -18- 1--- 19 -19- -APPLIED BORING LOG: HB-1 DATE: 4/6/2023 1991 PALOMAR AIRPORT RD Drawn By: JL VG CONSULTANTS CARLSBAD, CA _____,,.....,, ... ___.. Project Name: PALOMAR AIRPORT ROAD CARW ASH Date: ---'"'"4f ___ 6/=2=02=3 ____________ _ Address: 1991 PALOMAR AIRPORT RD Logged By:_--=JL=-'-V-=G---_________ _ CARLSBAD, CA Reviewed By:__..JE ... D...._ __________ _ Location: DESCENDING SLOPE (EL. 187) Footing Thickness (in.): Test Pit/Test Boring ID: HB-2 Depth (FT) Soil Description Excavation Method· HAND AUGER Depth to Water (ft): _ ____._,N.._.A.__ __ Sample Type: DISCRETE/ BULK Caving: _____ .._N .... O..,.NE....__ Total Deoth (ft): 3 Depth ofFootin~: NA Sample Discrete Bulle Lithology & Footing irype ID Sample Sample Details MC% Interval Interval 'i !::'., Grade-+-------------1---+---+--+---+--+---------+-- l -Poorly graded sand w/ Silt (SP-SM): -fine to medium grained, medium 2 -dense, yellowish brown poorly -graded sand with silt. --HB-2 2'-3' Artificial Fill (Documented) - 17.5 Tsa -Santiago Fonnation 3 1---i-----------llllf--+---l------i-.ii ......... llat ~ ~ -END OF BORING@ 3 FT 4 - - 5 - - 6 --7 --8 - 1-- 9 --10- 11 1---12--13i---14--15--16--17--18- 19- -APPLIED CONSULTANTS ---- BORING LOG: HB-2 1991 PALOMAR AIRPORT RD CARLSBAD, CA yd=104.17 pcf Dr=47.04% Medium Dense DATE: 4/6/2023 Drawn By: JL VG l -- 2- - 3 - - 4- - 5-- 6-- 7- - 8- -9_ - 10- 11- - 12- - 13- - 14- - 15- - 16- - 17- - 18- - 19- SLOPE STABILITY ANALYSIS 1991 Palomar Airport Rd - Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 31 of 36 Applied Consultants JLVG 1991 Palomar Airport Rd Slope Stability Analysis Slope stability analysis Input data Project Date: 4/11/2023 Settings USA -Safety factor Stability analysis Verification methodology: Safety factors (ASD) Earthquake analysis : Standard Safety factors Permanent design situation Safety factor : SFs = Safety factors Seismic design situation Safety factor : SF5 = Interface 1.50 (-] 1.00 [-] No. Interface location Coordinates of interface points [ft] 2 3 X 56.72 57.38 0.00 39.05 56.72 57.38 62.05 70.98 78.28 85.62 91.13 95.28 100.39 107.09 121 .21 26.27 27.77 z 25.68 24.00 26.07 25.77 25.68 24.00 26.18 23.00 20.00 17.00 14.00 11.00 8.00 5.00 2.00 26.07 25.40 X 56.72 26.27 49.60 56.72 61.38 62.05 72.90 81.57 87.67 92.60 96.71 102.31 109.19 26.27 27.77 z X 26.18 57.38 26.07 27.77 25.56 55.22 25.00 56.72 24.00 61.38 25.38 68.95 22.00 75.02 19.00 83.61 15.98 89.63 13.00 93.98 10.00 98.63 7.00 105.10 4.00 116.31 24.07 27.77 26.07 [GEO5 -Stopa Stability (32 bit) I version 5.2022.45.0 I hardware key 11398121 Applied Consultants I Copyright© 2022 Fine spol. s r.o. All Rights Reserved I wwv1.finesoftware.eu] (Gintegro. LLC [ 201.204.9560[ info@gintegm.oomj www gintegro.com] z 26.18 26.07 25.68 24.00 26.18 24.00 21.00 18.00 15.00 12.00 9.00 6.00 3.00 24.07 -~vrutD ~ Applied Consultants JLVG No. Interface location 4 5 6 7 8 Soil parameters -effective stress state No. Name 1 Artificial Fill 2 Santiago Formation 3 Water X 55.22 56.72 56.72 58.52 56.72 57.38 61.38 0.00 67.10 105.23 121.21 1991 Palomar Airport Rd Slope Stability Analysis Coordinates of interface points [ft] z 25.68 24.00 23.68 18.89 23.68 23.68 19.52 18.06 10.00 4.00 -0.12 Pattern X 55.22 56.72 62.05 57.38 57.38 61.38 33.52 79.61 115.09 z 23.68 19.52 18.89 23.68 19.52 24.00 14.00 8.00 2.00 30.00 31.50 0.00 X 56.72 56.72 62.05 57.38 58.52 48.86 88.87 120.27 Cef psf] 250.0 150.0 0.0 z 23.68 18.86 25.38 24.00 19.52 12.00 6.00 0.00 V [pct] 11 1.0 113.0 62.4 2 [GEO5 -Slope Stabilily (32 bit) I version 5.2022.45.0 I hardware key 11398 / 2 I Applied Consultants [Copyright© 2022 Fine spot. s r.o. All Righ1s Reserved I www.finesoftware.eu] [Ginlegro_ LLC 1201.204.95601info@gintegro.com1www.gintegro.com] Applied Consultants JLVG Soil parameters -uplift No. 1 Artificial Fill 2 Santiago Formation 3 Water Soil parameters Artificial Fill Unit weight : Stress-state : Angle of internal friction : Cohesion of soil : Saturated unit weight : Santiago Formation Unit weight : Stress-state : Angle of internal friction : Cohesion of soil : Saturated unit weight : Water Unit weight: Stress-state : Angle of internal friction : Cohesion of soil : Saturated unit weight : Rigid Bodies Name y = 111.0 pcf effective </>et= 30.00 ° Cef = Ysat = 250.0 psf 125.0 pcf y = 113.0 pcf effective cpef = 31 .50 ° Cef = 150.0 psf Ysat = 125.0 pcf y = 62.4 pcf effective cpef = 0.00 ° Cef = Ysat = o.o psf 62.4 pcf No. Name 1 Foundation 2 Retaining Wall Vsat 125.0 62.4 1991 Palomar A irport Rd Slope Stability Analysis Vs n Sample V [pct] 150.0 r: ~-·-· [·. ·, ! <'.\ ... " " 150.0 ,, .-1 l J • Cl-~. A ~_•.; 3 [GEOS • Slope Stability (32 bil) I version 5.2022.45.0 I hardware key 11398 / 2 I Applied Consultants I Copynght © 2022 Fine spol. s r.o. All Rights Reserved I www.finesoflware.eu] JGintegro. LLC 1201.204. 95601 info@gintegro.com1www.gintegro.com) Applied Consultants JLVG 1991 Palomar Airport Rd Slope Stability Analysis Assigning and surfaces No. 1 2 3 4 5 6 7 Surface position Coordinates of surface points [ft] Assigned X 26.27 27.77 26.27 56.72 57.38 56.72 55.22 56.72 z 24.07 25.40 26.07 25.00 24.00 26.18 23.68 24.00 X 27.77 27.77 56.72 57.38 56.72 56.72 56.72 z soil 24.07 F d 1. 26_07 oun a 10n 24•00 R t • • W II 26_18 e ammg a 25.68 --- 23.68 F d t· 25.00 oun a 10n - . ·----·----··----·--·· 56.72 57.38 56.72 57.38 61.38 57.38 61.38 57.38 56.72 25.68 23.68 24.00 19.52 19.52 24.00 19.52 19.52 23.68 55.22 57.38 56.72 58.52 61.38 57.38 58.52 57.38 56.72 25.68 "' ~ --24•00 R t • • W II 23_68 e a1rnng a 19•52 R t • -W II 23_68 e a1rnng a 19.52 "' A 56.72 18.86 58.52 18.89 i I>, ~ ' <J < .,,., ~ ~ 62.05 18.89 62.05 25.38 "- 62.05 26.18 61 .38 26.18 61 .38 24.00 33.52 14.00 48.86 12•00 Art'f· • I F"II 67.10 10.00 79.61 8_00 11c1a 1 88.87 6.00 105.23 4.00 115.09 2.00 120.27 0.00 121.21 -0.12 121.21 2.00 116.31 3.00 109.19 4.00 107.09 5.00 105.10 6.00 102.31 7.00 100.39 8.00 98.63 9.00 96.71 10.00 (GE05 -Slope Stability (32 bit) I version 5.2022.45.0 I hardware key 11398I2 f Applied Consultants I Copyright 0 2022 Fine spol. s r.o. All Rights Reserved I www.finesof1ware.eu) [Ginlegro, LLC 1201 .204.95601 info@gintegro.comJ 1vww.gintegro.com] ' (> -.:. 4 Applied Consultants JLVG No. Surface position 8 Surcharge No. Type 1 strip 2 strip 3 strip Surcharges No. 1 Foundation 2 Foundation 3 Basin Water Water type: No water Tensile crack Tensile crack not input. Type of action permanent permanent permanent Location z [ft] z= 24.00 z = 23.50 z= 18.80 1991 Palomar Airport Rd Slope Stability Analysis Coordinates of surface points [ft] Assigned X z X z soil 95.28 11.00 93,98 12.00 92,60 13.00 91.13 14.00 89.63 15.00 87.67 15.98 85.62 17.00 83.61 18.00 81 ,57 19.00 78.28 20.00 75.02 21.00 72.90 22.00 70.98 23.00 68.95 24.00 62.05 25.38 62.05 18.89 58.52 18.89 56.72 18.86 56.72 19.52 56.72 23.68 55.22 23.68 55.22 25.68 49.60 25.56 39.05 25.77 27.77 26.07 27.77 25.40 27.77 24.07 26.27 24.07 26.27 26.07 0.00 26.07 0.00 18.06 . - 120.27 0.00 115.09 2.00 S . F . 105.23 4.00 88,87 6_00 antIago ormatIon 79.61 8.00 67,10 10.00 48.86 12.00 33.52 14.00 0.00 18.06 0.00 -15.12 121.21 -15.12 121.21 -0.12 Origin Length Width Slope Magnitude X [ft] I [ft] b [ft] a[°] q, q1, f, q2,z unit F,x x= I= 2.00 0.00 2000.0 lbf/ft2 26.00 x = I = 2.00 0,00 2000.0 lbf/ft2 55.00 x= I= 5.50 0.00 2000.0 lbf/ft2 56.60 Name 5 [GEO5 -Slope Stability (32 bit) I version 5.2022.45.0 I hardware key 11398 / 2 I Applied Consultants I Copyright © 2022 Fine spol s r.o. All Rights Reserved I www.finesoftware.eu] [Gintegro, LLC 1201.204.95601 info@gintegro.com(www.glntagro.com] Applied Consultants JLVG Earthquake Horizontal seismic coefficient : Kh = 0.1700 Vertical seismic coefficient : Kv = 0.1700 Settings of the stage of construction Design situation : permanent Results (Stage of construction 1) Analysis 1 (stage 1) Circular slip surface Slip surface parameters I x= 85.80 . [ft] Center: i-~ -Angles: ' -· z= 80.80 [ft] . --1 ----Radius : R= 69.85 [ft] Analvsis of the slip surface without ootimization. Slope stability verification (Bishop) Sum of active forces : Fa= 20898.7 lbf/ft Sum of passive forces : Fp = 37778.0 lbf/ft Sliding moment: Ma= 1459776.8 lbfft/ft Resisting moment : Mp = 2638796.6 lbfft/ft Factor of safety= 1.81 > 1.50 SI •• Analysis 2 (stage 1) Circular slip surface Slip surface parameters Center: x = 96.43 [ft] Angles : z= 52.94 [ft] Analysis of the slip surface without optimization. i r --L_ 1991 Palomar Airport Rd Slope Stability Analysis a1 = -37.92 [0 ] . a2 =· 7.26 [0] a1 = -50.84 [0 J a2 = 2.38 [0 J 6 (GEO5. Slope Stability (32 bit) I version 5.2022.45.0 I hardware key 1139812 I Applied Consultants I Copyright© 2022 Fine spol. s r.o. All Rights Reserved I www.finesoftware.eu) (Gintegro, LLC I 201.204. 95601 info@gintegro.comJwviw.gin\egro.com] Applied Consultants JLVG Slip surface parameters Radius: R= 43.78 [ft] I Analysis of the slip surface without optimization. Slope stability verification (Bishop) Sum of active forces : Fa= 8754.2 lbf/ft Sum of passive forces : Fp = 18132.6 lbf/ft 1991 Palomar Airport Rd Slope Stability Analysis ___ Sliding moment : Ma = 383256.8 lbfft/ft ___________________________ _ Resisting moment: M~ = 793846.7 lbfft/ft Factor of safety= 2.07 > 1.50 s • Sta e -anal sis : 1 -2 [GE05 -Slope Stabllrty (32 bit) I version 5.2022.45.D I hardware key 11398 / 2 I Applied Consullanls I Copyright© 2022 Fine spol. s r.o. All Rights Reserved I www.ftnesoftware.eu] [Gintegro, LLC 1201.204 95601 info@gintegro.com1 www.gintegro.oorn] 7 Applied Consultants JLVG Input data (Stage of construction 2) Assigning and surfaces No. Surface position 2 3 4 5 6 1991 Palomar Airport Rd Slope Stability Analysis Coordinates of surface points [ft] Assigned X z X z soil 26.27 24.07 27.77 24.07 Foundation 27.77 25.40 27.77 26.07 -~--·- 26.27 26.07 56.72 25.00 56.72 24•00 R t • • W II 57.38 24.00 57.38 26_ 18 e aInmg a 56.72 26.18 56.72 25.68 r I /- "' l!. -I 55.22 23.68 56.72 23.68 56.72 24.00 56.72 25.00 Foundation 56.72 25.68 55.22 25.68 t <; 1 <! .d .,,,__,___e_ 57.38 23.68 57.38 24.00 R • • W II 56.72 24.00 56.72 23_68 etammg a ,:, '\ t '\ ' ( < 57.38 19.52 58.52 19.52 61.38 19.52 61.38 24_00 Water 57.38 24.00 57.38 23.68 61.38 19.52 58.52 19.52 R . . W II 57.38 19.52 57.38 23_68 etaImng a 56.72 23.68 56.72 19.52 ' <:. <:, 56.72 18.86 58.52 18.89 ~p .. ,1 ,'> n ,.,. 62.05 18.89 62.05 25.38 , t· ... , , ___ :: ":- 62.05 26.18 61.38 26.18 61 .38 24.00 8 (GEO5 -Slope Stability (32 bil) I version 5.2022.45.0 I hardware key 11398 / 2 I Applied Consultants I Copyright© 2022 Fine spol. s r.o. All Rights Reserved I www.finesoftware.eu( (Ginlegro. LLC 1201.204 95601 info@ginlegro.com1 VM'W.gintegro com] Applied Consultants JLVG No. Surface position 7 8 Surcharge Surcharge No. Type Type of new change action 1 No No strip permanent 2 No No strip permanent 3 No No strip permanent Surcharges No. 1 Foundation 2 Foundation 1991 Palomar Airport Rd Slope Stability Analysis Coordinates of surface points [ft] Assigned X z X z soil 33.52 14.00 48.86 12•00 Art·t· • I F·11 67.10 10.00 79.61 8_00 11c1a 1 88.87 6.00 105.23 4.00 115.09 2.00 120.27 0.00 l. 121.21 -0.12 121.21 2.00 116.31 3.00 109.19 4.00 107.09 5.00 105.10 6.00 102.31 7.00 100.39 8.00 98.63 9.00 96.71 10.00 95.28 11.00 93.98 12.00 92.60 13.00 91.13 14.00 89.63 15.00 87.67 15.98 85.62 17.00 83.61 18.00 81.57 19.00 78.28 20.00 75.02 21.00 72.90 22.00 70.98 23.00 68.95 24.00 62.05 25.38 62.05 18.89 58.52 18.89 56.72 18.86 56.72 19.52 56.72 23.68 55.22 23.68 55.22 25.68 49.60 25.56 39.05 25.77 27.77 26.07 27.77 25.40 ' 27.77 24.07 26.27 24.07 26.27 26.07 0.00 26.07 0.00 18.06 120.27 0.00 115.09 2.00 S t· F t· 105.23 4.00 88.87 6_00 an 1ago orma 10n 79.61 8.00 67.10 10.00 48.86 12.00 33.52 14.00 0.00 18.06 0.00 -15.12 121.21 -15.12 121.21 -0.12 Location Origin Length Width Slope Magnitude q, q1, z {ft] X [ft] I [ft] b [ft] a[°] Q2,z unit f, F,x z= x= 0.00 2000.0 lbf/ft2 24.00 26.00 I= 2.00 z= x= 0.00 2000.0 lbf/ft2 23.50 55.00 I = 2.00 z= x= 0.00 2000.0 lbf/ft2 18.80 56.60 I = 5.50 Name 9 [GEOS -Slape Stability (32 bit) I version 5.2022.45.0 I hardware key 11398 /2 I Applied Consultants I Copyright© 2022 Fine spol. s r.o. All Rights Reserved I wv,w.finesoftware.eu] [Gintegro, LLC I 201.204.9560Iinfo@gintegro.comI1w.w.ginlegro.com] Applied Consultants -~JAmltJI J LVG ~ No. 3 Basin Water Water type : No water Tensile crack Tensile crack not input. Earthquake Horizontal seismic coefficient : Kh = 0.1700 Vertical seismic coefficient : Kv = 0.1700 Settings of the stage of construction Design situation : seismic Results (Stage of construction 2) Analysis 1 (stage 2) Circular slip surface Name Slip surface parameters I x= 85.80 [ft] Center : Angles: z= 80.80 [ft] Radius: I R= 69.85 rftl I Analysis of the slip surface without optimization. Slope stability verification (Bishop) Sum of active forces: Fa= 20898.7 lbf/ft Sum of passive forces: Fp = 37778.0 lbf/ft Sliding moment: Ma= 1459776.8 lbfft/ft Resisting moment : Mp= 2638796.6 lbfft/ft Factor of safety= 1.81 > 1.00 Slope stability ACCEPT ABLE I > 1991 Palomar Airport Rd Slope Stability Analysis a1 = -37.92 1°I a2 = 7.26 [°) 10 [GEO5 . Slope Stability (32 bit) I version 5.2022.45.0 I hardware key 11398 / 2 I Applied Consultants J Copynghl © 2022 Fine spal s r.o. All Rights Reserved I www finesaftware.eu] [Ginlegro, LLC 1201.204.95601 info@gintegro.comJ www.ginlegro.comJ Applied Consultants JLVG Name : Seismic Slo Analysis 2 (stage 2) Circular slip surface Slip surface parameters I x= 96.43 [ft] Center: f . --Angles : I z= 52.94 : [ft] Radius: R= 43.78, [ft] Analvsis of the slip surface without optimization. Slope stability verification (Bishop) Sum of active forces : Fa= 8754.2 lbf/ft Sum of passive forces : Fp = 18132.6 lbf/ft Sliding moment: Ma= 383256.8 lbfft/ft Resisting moment : Mp = 793846.7 lbfft/ft Factor of safety= 2.07 > 1.00 Slo e stab iii ACCEPT ABLE t ; 1991 Palomar Airport Rd Slope Stability Analysis 01 = -50.84 : [0] ·-- 02 = 2.38 [°] Sta e -anal sis : 2 -2 11 [GEO5 -Slope Stability (32 bit) I version 5.2022.45.0 I hardware key 11398 / 2 I Applied Consultants I Copyright <ti 2022 Fine spol. s r.o. All Rights Reserved I www.finesoftware.eu) [Gintegro, LLC 1201.204.95601 info@ginlegro coml www.gintegro.com) GENERAL EARTHWORK AND GRADING GUIDELINES 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 32 of 36 GENERAL EARTHWORK AND GRADING GUIDELINES I. EARTHWORK OBSERVATION AND TESTING Prior to commencement of grading, a qualified geotechnical consultant should be employed for the purpose of observing earthwork procedures and testing the fills and cut slopes for conformance with the recommendations of the geotechnical report and these specifications. The consultant is to provide adequate testing and observation so that he may determine that the work was accomplished as specified. It should be the responsibility of the contractor to assist the consultant and keep him apprised of work schedules and changes so that the consultant may schedule his personnel accordingly. The contractor is to provide adequate equipment and methods to accomplish the work in accordance with applicable grading codes or agency ordinances, these specifications, and the approved grading plans. If in the opinion of the consultant, unsatisfactory conditions are resulting in a quality of work less than required in these specifications, the consultant may reject the work and recommend that construction be stopped until the conditions are rectified. Maximum dry density tests used to determine the degree of compaction should be performed in accordance with the American Society for Testing and Materials Test Method ASTM: D 1557. II. PREPARATION OF AREAS TO BE FILLED 1. Clearing and Grubbing: All brush, vegetation, and debris shall be removed and properly disposed of. The Geotechnical Consultant shall evaluate the extent of removal of these items depending on site conditions. Fill material shall not contain more than 1 percent of organic material by volume. No fill should contain more than 5 percent organic matter. No fill shall contain hazardous materials or asphalt pavement. If asphalt pavement is removed, it should be disposed of at an appropriate location. Concrete fragments which are free of reinforcing steel may be placed in the fills. 2. Processing: the existing ground which is evaluated to be satisfactory for support of fill shall be scarified to a minimum depth of 6 inches. Existing ground which is not satisfactory shall be over-excavated as specified in the following section. Scarification shall continue until the soils are broken down and free of large clay lumps or clods and until the working surface is reasonably uniform and free of uneven features which would inhibit uniform compaction. 3. Overexcavation: Soft, dry, spongy, saturated or otherwise unsuitable ground, extending to such a depth that surface processing cannot adequately improve the condition, shall be over-excavated down to firm ground as approved by the consultant. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 33 of36 4. Moisture Conditioning: Over-excavated and processed soils shall be watered, dried-back, blended, and/or mixed, as necessary to attain a uniform moisture content approximately 2 percent over optimum. 5. Recompaction: Over-excavated and processed soils which have been properly mixed and moisture-conditioned shall be compacted to a minimum relative compaction of 90 percent according to ASTM: D1557. 6. Benching: Where fills are to be placed on ground with slopes steeper than 5: 1 (horizontal to vertical units), the ground shall be benched. The lowest bench shall be: a minimum of 15 feet wide, at least 2 feet deep with a minimum 2% slope into the fill bank for horizontal stability, expose firm materials, and be approved by the consultant. Other benches shall excavate into firm material for a minimum width of 4 feet. Ground sloping flatter than 5: 1 shall be benched or otherwise over-excavated when considered necessary by the consultant. 7. Approval: All areas to receive fill, including processed areas, removal areas, and toe-of-fill benches shall be approved by the consultant prior to fill placement. III. FILL MATERIAL 1. General: Material to be placed as fill shall be free of organic matter and other deleterious substances, and shall be approved by the consultant. Soils of poor gradation, expansion, or strength characteristics shall be placed in areas designated by the consultant or mixed with other soils until suitable to serve as satisfactory fill material. 2. Oversize: Oversize material defined as rock, or other irreducible material, with a maximum dimension of greater than 12 inches, shall not be buried or placed in fill unless the location, materials, and disposal methods are specifically approved by the consultant. Oversize disposal operations shall be such that nesting of oversized material does not occur, and such that the oversized material is completed surrounded by compacted or densified fill. Oversize material shall not be placed within the range of future utilities or underground construction, unless specifically approved by the consultant. 3. Import: If import fill is necessary for grading, the import material shall be approved by the geotechnical consultant. IV. FILL PLACEMENT AND COMPACTION 1. Fill Lifts: Approved fill material shall be placed in areas prepared to receive fill in near-horizontal layers not exceeding 6 to 8 inches in compacted thickness. The consultant may approve thicker lifts if testing indicates that the grading procedures are such that adequate compaction is being achieved with lifts of greater thickness. Each layer shall be spread evenly and shall be thoroughly mixed during spreading to attain uniformity of material and moisture in each layer. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JLVG/BMH 4/7/2023 Page 34 of36 2. Fill Moisture: Fill layers at a moisture content less than optimum shall be watered and mixed, and wet fill layers shall be aerated by scarification or blended with drier materials. Moisture conditioning and mixing of fill layers shall continue until the fill material is at a uniform moisture content at or near two percent over optimum. 3. Compaction of Fill: After each layer has been evenly spread, moisture conditioned and mixed, it shall be uniformly compacted to not less than 90 percent of maximum dry density in accordance with ASTM: D1557. Compaction equipment shall be adequately sized and either specifically designed for soil compaction or of proven reliability, to efficiently achieve the specified degree of compaction. 4. Fill Slopes: Compacting of slopes shall be accomplished, in addition to normal compaction procedures, by backrolling of slopes with sheepsfoot rollers at frequent intervals of 2 to 3 feet in fill elevation gain, or by other methods producing satisfactory results. At the completion of grading, the relative compaction of the slope out to the slope face shall be at least 90 percent. 5. Compaction Testing: Field tests to check the fill moisture and degree of compaction will be performed by the consultant. The location and frequency of tests shall be at the consultant's discretion. In general, the tests shall be taken at an interval not exceeding 2 feet in vertical rise and/or every 1000 cubic yards of embankment. V. SUBDRAIN INSTALLATION Subdrain systems, if required, shall be installed in approved ground to conform to the approximate alignment and details shown on the plans or shown herein. The subdrain location or materials should not be changed or modified without the approval of the consultant. The consultant, however, may recommend and upon approval, direct changes in subdrain line, grade or material. All subdrains shall be surveyed for line and grade after installation and sufficient time allowed for surveys, prior to commencement of filling over the subdrains. VI. EXCAVATIONS Excavations and cut slopes shall be examined during grading. If directed by the consultant, further excavation or overexcavation and refilling of cut areas shall be performed, and/or remedial grading of cut slopes performed. Where fill-over-cut slopes are to be graded, unless otherwise approved, the cut portion of the slope shall be made and approved by the consultant prior to placement of the fill portion of the slope. Excavations may require the consultant to produce an alternate sloping plan if the excavation VII. TRENCH BACKFILL 1. The Contractor shall follow all OSHA and CAL/OSHA requirements for maintaining safety of trench excavations. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/712023 Page 35 of 36 2. The bedding and backfill of utility trenches should be done with the applicable provisions of Standard Specifications of Public Works Construction. Bedding material should have a sand equivalent of (SE >30). Bedding should be placed 1 foot above the top of pipe. All backfill should be compacted to 90 percent from 1 foot above the pipe to the surface. 3. The geotechnical consultant should test the trench backfill for relative compaction. At least one test should be performed for every 300 feet of trench and every two feet of trench fill. 4. The lift thickness of the trench backfill shall not exceed what is allowed in the Specifications of Public Works Construction unless the contractor can demonstrate that the fill can be compacted by an alternative means to the minimum relative compaction. 5. All work associated with trenches, excavations and shoring must conform to the local regulatory requirements, State of California Division oflndustrial Safety Codes, and Federal OSHA requirements. VIII. FOUNDATIONS NEAR TOP OF SLOPES Where foundations, footings, walls and other similar proposed structures are to be located seven feet and further away from the top of slopes, standard design may take place in conformance with the recommended soil bearing value. In situations where foundations, footings, walls, et cetera, are located closer than seven feet from the top of slope they shall be deepened so that the bottom edge of the footing is 7 feet horizontally from daylight in the slope. 1991 Palomar Airport Rd -Updated Preliminary Geotechnical Investigation JL VG/BMH 4/7/2023 Page 36 of 36