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5503-14; POINSETTIA LIFT STATION HYDRAULIC SURGE PROTECTION; UPDATE GEOTECHNICAL EVALUATION; POINSETTIA LIFT STATION IMPROVEMENTS; 2020-01-24
Update Geotechnical Evaluation Poinsettia Lift Station Improvements Carlsbad, California Kennedy Jenks 9325 Sky Park Court, Suite 200 | San Diego, California 92123 January 24, 2020 | Project No. 107544015 Geotechnical | Environmental | Construction Inspection & Testing | Forensic Engineering & Expert Witness Geophysics | Engineering Geology | Laboratory Testing | Industrial Hygiene | Occupational Safety | Air Quality | GIS Project ID: 5503-14 DWG 486-6A 5710 Ruffin Road | San Diego, California 92123 | p. 858.576.1000 | www.ninyoandmoore.com Update Geotechnical Evaluation Poinsettia Lift Station Improvements Carlsbad, California Mr. Roy Yu, PE Kennedy Jenks 9325 Sky Park Court, Suite 300 | San Diego, California 92123 January 24, 2020 | Project No. 107544015 Nissa M. Morton, PG, CEG Project Geologist William R. Morrison, PE, GE Senior Engineer Gregory T. Farrand, PG, CEG Principal Geologist NMM/WRM/GTF/RSH/atf Distribution: (1) Addressee (via e-mail) Geotechnical & Environmental Sciences Consultants Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 i CONTENTS 1 INTRODUCTION 1 2 SCOPE OF SERVICES 1 3 SITE AND PROJECT DESCRIPTION 1 4 SUBSURFACE EVALUATION AND LABORATORY TESTING 2 5 GEOLOGIC AND SUBSURFACE CONDITIONS 2 5.1 Regional Geologic Setting 2 5.2 Site Geology 3 5.2.1 Fill 3 5.2.2 Alluvium 3 5.2.3 Santiago Formation 4 5.3 Groundwater 4 6 GEOLOGIC HAZARDS 4 6.1 Faulting and Seismicity 4 6.1.1 Surface Ground Rupture 5 6.1.2 Ground Motion 5 6.2 Landsliding and Slope Stability 7 7 CONCLUSIONS 7 8 RECOMMENDATIONS 8 8.1 Earthwork 8 8.1.1 Pre-Construction Conference 8 8.1.2 Site Preparation 9 8.1.3 Remedial Grading 9 8.1.4 Temporary Excavations 9 8.1.5 Shoring and Braced Excavations 10 8.1.6 Construction Dewatering 11 8.1.7 Mitigation of Unstable Excavation Bottoms 11 8.1.8 Materials for Fill 11 8.1.9 Compacted Fill 12 8.1.10 Lateral Pressures for Thrust Blocks 13 8.1.11 Pipe Bedding and Modulus of Soil Reaction (E’) 13 8.1.12 Pipe Zone Backfill 14 Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 ii 8.1.13 Utility Trench Zone Backfill 14 8.1.14 Drainage 14 8.2 Seismic Design Parameters 15 8.3 Foundations 15 8.3.1 Mat Foundations 15 8.3.2 Lateral Resistance 16 8.3.3 Static Settlement 16 8.4 Underground Structures 16 8.5 Uplift and Special Design Considerations 17 8.6 Concrete Flatwork 17 8.7 Corrosivity 17 8.8 Concrete 18 8.9 Preliminary Pavement Recommendations 18 9 CONSTRUCTION OBSERVATION 19 10 LIMITATIONS 20 11 REFERENCES 21 TABLES 1 – 2019 California Building Code Seismic Design Criteria 15 2 – Preliminary Flexible Pavement Recommendations 19 FIGURES 1 – Site Location 2 – Boring Locations 3 – Geology 4 – Fault Locations 5 – Acceleration Response Spectra 6 – Lateral Earth Pressures for Temporary Cantilevered Shoring below Groundwater 7 – Lateral Earth Pressures for Braced Excavation Below Groundwater (Stiff Clay) 8 – Thrust Block Lateral Earth Pressure Diagram 9 – Lateral Earth Pressures for Underground Structures 10 – Uplift Resistance Diagram for Underground Structures Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 iii APPENDICES A – Boring Logs B – Laboratory Testing Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 1 1 INTRODUCTION In accordance with your authorization and our proposal dated December 6, 2019, we have performed an update to our geotechnical evaluation report prepared for the Poinsettia Lift Station located on Poinsettia Lane in Carlsbad, California (Figure 1). Our previous report dated June 10, 2015 (Ninyo & Moore, 2015) provides findings and recommendations relative to the emergency storage basin, which has since been constructed. New improvements planned for the site include a surge tank and associated piping. This report presents our previous findings, along with recommendations for the additional improvements that are planned at the site in accordance with the 2019 Californian Building Code (CBC). 2 SCOPE OF SERVICES To date, our scope of services has included the following: • Review of readily available published and in-house geotechnical literature, site plans, topographic maps, geologic maps, fault maps, and stereoscopic aerial photographs. • Performing a field reconnaissance to observe existing site conditions and to locate and mark our exploratory boring locations. • Coordinating with Underground Service Alert (USA) to clear our boring locations of potential conflicts with underground utilities prior to our subsurface exploration. • Performing a subsurface exploration that consisted of drilling, logging, and sampling of two exploratory borings for the emergency storage basin project at the existing lift station at the site (Ninyo & Moore, 2015). Bulk and relatively undisturbed drive samples of soil were collected at selected intervals from the borings and transported to our in-house geotechnical laboratory for testing. • Performing geotechnical laboratory testing on selected soil samples to evaluate soil parameters for design purposes that included in-situ dry density and moisture content, gradation, Atterberg Limits, consolidation, direct shear, R-value, and soil corrosivity. • Performing a site-specific ground response analysis in accordance with the 2019 CBC. • Compiling and analyzing the data obtained from our background review, and from our prior subsurface exploration and laboratory testing (Ninyo & Moore, 2015). • Preparing this updated report presenting our findings, conclusions, and recommendations regarding the geotechnical design and construction of the project. 3 SITE AND PROJECT DESCRIPTION The City of Carlsbad’s Poinsettia Lift Station is located on the north side of Poinsettia Lane, east of Alicante Road in Carlsbad, California (Figure 1). The site is bounded by a residential development to the north and east, Poinsettia Lane to the south, and an open natural vegetation Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 2 area to the west. The site is relatively flat and covered with asphalt concrete pavement. Two existing buildings, a pump structure, piping and other associated improvements are located at the site. The site elevation is approximately 110 feet above mean sea level (MSL). Surface drainage is generally by sheet flow to the south towards Poinsettia Lane. As discussed previously, we performed an evaluation in 2015 for the emergency storage basin at the site (Ninyo & Moore, 2015), which has since been constructed. Current improvements planned at the site include a surge tank and associated piping. The proposed improvements will be generally located in the northwest portion of the existing lift station site (Figure 2). We anticipate grading for the proposed improvements will consist of minor cuts and fills (a few feet from existing grades). 4 SUBSURFACE EVALUATION AND LABORATORY TESTING Our previous subsurface exploration was conducted on May 6, 2015 and consisted of drilling, logging, and sampling two exploratory borings. The borings were drilled to depths of up to 46.5 feet below existing grades with a truck mounted drill rig equipped with hollow stem augers. Soil samples were obtained at selected intervals from the borings. The samples were then transported to our in-house geotechnical laboratory for testing. The approximate locations of the exploratory borings are shown on Figure 2. Logs of the borings are included in Appendix A. Laboratory testing of representative soil samples included in-situ dry density and moisture content, gradation, Atterberg Limits, consolidation, direct shear, R-value, and soil corrosivity. The results of the in-situ dry density and moisture content tests are presented on the boring logs in Appendix A. The results of the other laboratory tests described above are presented in Appendix B. 5 GEOLOGIC AND SUBSURFACE CONDITIONS Our findings regarding regional and site geology and groundwater conditions are provided in the following sections. 5.1 Regional Geologic Setting The project area is situated in the western portion of the Peninsular Ranges Geomorphic Province. This geomorphic province encompasses an area that extends approximately 900 miles from the Transverse Ranges and the Los Angeles Basin south to the southern tip of Baja California (Norris and Webb, 1990; Harden, 2004). The province varies in width from approximately 30 to 100 miles and generally consists of rugged mountains underlain by Jurassic Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 3 metavolcanic and metasedimentary rocks, and Cretaceous igneous rocks of the southern California batholith. The portion of the province in western San Diego County that includes the project area generally consists of uplifted and dissected coastal plain underlain by Tertiary- and Quaternary-age sedimentary rocks, including the Santiago Formation (Figure 3). The Peninsular Ranges Province is traversed by a group of sub-parallel faults and fault zones trending roughly northwest. Several of these faults, which are shown on Figure 4, are considered active faults. The Elsinore, San Jacinto, and San Andreas faults are active fault systems located northeast of the project area and the Rose Canyon, Coronado Bank, San Diego Trough, and San Clemente faults are active faults located west of the project area. The Rose Canyon Fault Zone, the nearest active fault system, has been mapped approximately 7 miles west of the project site. Major tectonic activity associated with these faults within this regional tectonic framework consists primarily of right-lateral, strike-slip movement. Further discussion of faulting relative to the site is provided in the Faulting and Seismicity and Seismic Hazards section of this report. 5.2 Site Geology The geology of the site vicinity is shown on Figure 3. Materials encountered during our subsurface exploration included fill materials, alluvium, and materials of the Santiago Formation (Kennedy and Tan, 2008). Generalized descriptions of the earth units encountered during our field reconnaissance and subsurface exploration are provided in the subsequent sections. Additional descriptions of the subsurface units are provided on the boring logs in Appendix A. 5.2.1 Fill Fill materials were encountered in both of our borings beneath existing pavements to depths of up to 8 feet. As encountered during our subsurface exploration, the fill consists of gray, moist, very stiff, silty clay. Documentation of the placement and compaction of existing fill was not available for our review. 5.2.2 Alluvium Alluvium was encountered in our borings beneath the fill and was observed to extend to depths of up to 29 feet. As encountered in our exploratory borings, the alluvium generally consists of various shades of gray and brown, moist to wet, very stiff to hard, silty clay, sandy clay, and fat clay. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 4 5.2.3 Santiago Formation Materials of the Tertiary-age Santiago Formation were encountered in both of our borings underlying the alluvium and were observed to the total depths explored of up to 46½ feet. As encountered, the Santiago Formation generally consists of various shades of gray to brown, wet, weakly to moderately cemented silty sandstone and moderately indurated sandy siltstone. 5.3 Groundwater Groundwater was encountered during our subsurface exploration in our boring B-1 at a depth of approximately 22 feet and in our boring B-2 at a depth of approximately 12 feet. Relatively high moisture contents measured within samples obtained from depths shallower than the observed groundwater surface indicate that the static groundwater surface could be at depths on the order of 5 feet or less. Fluctuations in the groundwater level and perched conditions typically occur due to variations in precipitation, ground surface topography, subsurface stratification, irrigation, and other factors. 6 GEOLOGIC HAZARDS In general, hazards associated with seismic activity include strong ground motion, ground surface rupture, and liquefaction. These considerations and other geologic hazards such as landsliding are discussed in the following sections. 6.1 Faulting and Seismicity The project area is considered to be seismically active. Based on our review of the referenced geologic maps as well as on our site reconnaissance, the subject site is not underlain by known active or potentially active faults (i.e., faults that exhibit evidence of ground displacement in the last 11,000 years and 2,000,000 years, respectively). However, the site is located in a seismically active area, as is the majority of southern California, and the potential for strong ground motion is considered significant during the design life of the proposed structure. The nearest known active fault is the Rose Canyon Fault, located approximately 7 miles west of the site (Figure 4). In general, hazards associated with seismic activity include ground surface rupture, strong ground motion, liquefaction, and seismically induced settlement. A brief description of these hazards and the potential for their occurrences on site are discussed below. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 5 6.1.1 Surface Ground Rupture There are no known active faults crossing the subject site, and the potential for ground rupture due to faulting is considered low. The potential for surface ground cracking related to shaking from distant events is also considered low. 6.1.2 Ground Motion As previously discussed, materials encountered in our borings included fill, alluvium, and materials of the Santiago Formation. Based on the subsurface data disclosed by our exploratory borings (Appendix A), along with our previous experience at the site, the site is considered Seismic Site Class D. The 2019 CBC specifies that the Risk-Targeted, Maximum Considered Earthquake (MCER) ground motion response accelerations be used to evaluate seismic loads for design of buildings and other structures. Per the 2019 CBC, a site-specific ground motion hazard analysis shall be performed for structures on Site Class D with a mapped MCER, 5 percent damped, spectral response acceleration parameter at a period of 1 second (S1) greater than or equal to 0.2g in accordance with Sections 21.2 and 21.3 of the American Society of Civil Engineers (ASCE) Publication 7-16 for the Minimum Design Loads and Associated Criteria for Building and Other Structures. We calculated that the S1 for the site is equal to 0.35g using the 2019 Structural Engineers Association of California [SEAOC]/Office of Statewide Health Planning and Development [OSHPD] seismic design tool (web-based); therefore, a site-specific ground motion hazard analysis was performed for the project site. The site-specific ground motion hazard analysis consisted of the review of available seismologic information for nearby faults and performance of probabilistic seismic hazard analysis (PSHA) and deterministic seismic hazard analysis (DSHA) to develop acceleration response spectrum (ARS) curves corresponding to the MCER for 5 percent damping. Prior to the site-specific ground motion hazard analysis, we obtained the mapped seismic ground motion values and developed the general MCER response spectrum for 5 percent damping in accordance with Section 11.4 of ASCE 7-16. The average shear wave velocity (VS) for the upper 30 meters of soil (VS30) is mapped to be 515 meters per second (m/s) (Wills and Clahan, 2006) and the depths to VS = 1,000 m/s and VS = 2,500 m/s are assumed to be 40 meters and 210 meters, respectively (Southern California Earthquake Center [SCEC] Community Velocity Model Version 11.9.0 Basin Depth). These values were evaluated using the Open Seismic Hazard Analysis software developed by USGS and SCEC (2019). However, based on the standard penetration test blow counts obtained during our Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 6 subsurface exploration, along with published correlations between standard penetration test blow counts and VS30 values (Brandenberg, et al, 2010), a Vs30 value of 310 m/s was used for our site-specific analysis. The 2014 new generation attenuation (NGA) West-2 relationships were used to evaluate the site-specific ground motions. The NGA relationships that we used for developing the probabilistic and deterministic response spectra are by Chiou and Youngs (2014), Campbell and Bozorgnia (2014), Boore, Stewart, Seyhan, and Atkinson (2014), and Abrahamson, Silva, and Kamai (2014). The Open Seismic Hazard Analysis software developed by USGS and SCEC (2019) was used for performing the PSHA. The Calculation of Weighted Average 2014 NGA Models spreadsheet by the Pacific Earthquake Engineering Research Center (PEER) was used for performing the DSHA (Seyhan, 2014). PSHA was performed for earthquake hazards having a 2 percent chance of being exceeded in 50 years multiplied by the risk coefficients per ASCE 7-16. The maximum rotated components of ground motions were considered in PSHA with 5 percent damping. For the DSHA, we analyzed accelerations from characteristic earthquakes on active faults within the region using the California Department of Transportation (Caltrans) ARS (Caltrans, 2019) seismic design tool (web-based) and the hazard curves and deaggregation plots at the site using the USGS Unified Hazard Tool application (USGS, 2019b). A magnitude 7.0 seismic event on the Rose Canyon fault with a rupture distance of 11.34 kilometers from the site was evaluated to be the controlling earthquake. Hence, the deterministic seismic hazard analysis was performed for the site using this event and corrections were made to the spectral accelerations for the 84th percentile of the maximum rotated component of ground motion with 5 percent damping. The site-specific MCER response spectrum was taken as the lesser of the spectral response acceleration at any period from the PSHA and DSHA, and the site-specific general response spectrum was determined by taking two-thirds of the MCER response spectrum with some conditions in accordance with Section 21.3 of ASCE 7-16. Figure 6 presents the site-specific MCER response spectrum and the site-specific design response spectrum. The general mapped design response spectrum calculated in accordance with Section 11.4 of ASCE 7-16 is also presented on Figure 6 for comparison. The site-specific spectral response acceleration parameters, consistent with the 2019 CBC, are provided in Section 11.2 for the evaluation of seismic loads on buildings and other structures. The site-specific Maximum Considered Earthquake Geometric Mean (MCEG) peak ground acceleration (PGAM) was calculated as 0.513g. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 7 6.1.3 Liquefaction and Seismically Induced Settlement Liquefaction is the phenomenon in which loosely deposited granular soils with silt and clay contents of less than approximately 35 percent and non-plastic silts located below the water table undergo rapid loss of shear strength when subjected to strong earthquake- induced ground shaking. Ground shaking of sufficient duration results in the loss of grain- to-grain contact due to a rapid rise in pore water pressure, and causes the soil to behave as a fluid for a short period of time. Liquefaction is known generally to occur in saturated or near-saturated cohesionless soils at depths shallower than 50 feet below the ground surface. Factors known to influence liquefaction potential include composition and thickness of soil layers, grain size, relative density, groundwater level, degree of saturation, and both intensity and duration of ground shaking. As noted above in Section 5.2.2 and in our exploratory borings (Appendix A), the encountered portions of the alluvium were observed to generally consist of silty clay, sandy clay, and fat clay. Based on guidelines outlined by Bray and Sancio (2006), we conclude that the alluvium is not susceptible to liquefaction or seismic induced settlement, due to its clayey nature. 6.2 Landsliding and Slope Stability No landslides or indications of deep-seated landslides were noted underlying the project site during our field exploration (Ninyo & Moore, 2015) or our review of available geologic literature and topographic maps. 7 CONCLUSIONS Based on our review of the referenced background data, geologic field reconnaissance, subsurface exploration, and laboratory testing, it is our opinion that construction of the proposed project is feasible from a geotechnical standpoint. Geotechnical considerations include the following: • The project site is generally underlain by fill materials, alluvium, and the Santiago Formation. The existing fill soils are not considered suitable for structural support of the proposed improvements in their current condition. • Groundwater was encountered during our subsurface exploration at a depth of approximately 12 feet below the ground surface. The relatively high moisture contents measured in samples obtained from depths shallower than the observed groundwater surface suggest that the static groundwater level could be at a depth of 5 feet or less. Groundwater will be a constraint during construction and the contractor should anticipate dewatering prior to the excavation for the proposed surge tank and its associated improvements. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 8 • Wet materials were encountered in our exploratory borings. Therefore, unstable excavation bottoms and caving soils should be anticipated. The contractor should anticipate and be prepared to address these conditions. • Wet soils encountered on the site will require additional handling prior to their being reused as fill. • Based on the results of our exploratory borings and our experience with similar soils, it is our opinion that the on-site fill and alluvial materials can be excavated using heavy duty earthmoving equipment in good working condition. • The results of our subsurface evaluation indicate that the alluvial soils that underlie the site are not susceptible to liquefaction or seismically induced settlement. • We anticipate that the new surge tank will be constructed on mat foundations. The mat foundation can be expected to tolerate estimated total and differential settlements, as well as buoyant/uplift forces, provided they are designed in accordance with the recommendations contained herein. • Based on the results of our soil corrosivity tests and Caltrans (2018) criteria, the on-site soils would be classified as corrosive. As such, we recommend that a corrosion engineer be consulted for further evaluation of these soils. 8 RECOMMENDATIONS The following sections include our geotechnical recommendations for the proposed improvements. These recommendations are based on our evaluation of the site geotechnical conditions and our understanding of the planned construction, including anticipated foundation loads. The proposed site improvements should be constructed in accordance with the requirements of applicable governing agencies. 8.1 Earthwork In general, earthwork should be performed in accordance with the recommendations presented in this report. Ninyo & Moore should be contacted for questions regarding the recommendations or guidelines presented herein. 8.1.1 Pre-Construction Conference We recommend that a pre-construction conference be held. The City of Carlsbad and/or their representative, the governing agencies’ representatives, the civil engineer, the architect, Ninyo & Moore, and the contractor should be in attendance to discuss the work plan and project schedule and earthwork requirements. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 9 8.1.2 Site Preparation Prior to performing excavations or other earthwork, the site should be cleared of existing fill soils, debris, vegetation, and loose or otherwise unsuitable soils. Obstructions that extend below the finished grade (such as tree stumps or buried structures) should be removed and the resulting holes filled with compacted soil. Materials generated from the clearing operations should be removed from the project site and disposed of at a legal disposal site. 8.1.3 Remedial Grading Due to the lack of literature documenting the placement and compaction of existing fills, we recommend that the existing fill soils be removed and replaced with compacted fill in those areas of the site where slabs-on-grade and shallow foundations are planned. Based on the results of our subsurface exploration, we anticipate that the depths of these removals could extend 8 feet or more below the existing ground surface. In general, remedial grading should extend 5 feet or more beyond the outer edge of the structure footprint, as practical. Ninyo & Moore should observe the excavations prior to filling to evaluate the need for deeper removals. Deeper removals may be needed at specific locations if loose, compressible, or otherwise unsuitable materials are exposed during grading. The removals should be replaced with compacted fill in accordance with this report. Excavations for the surge tank, associated piping, and other underground improvements are anticipated to expose soft and wet materials after dewatering. Therefore, we recommend that the excavation be overexcavated a depth of approximately 2 feet below the proposed subgrade elevation. The overexcavated material should be replaced with compacted fill in accordance with Sections 8.1.8 and 8.1.9 to a depth of approximately 1 foot below subgrade elevation, unless unstable conditions are encountered. We recommend that a 1-foot-thick crushed rock or lean concrete base course be placed at the bottom of the excavation (i.e., on top of the compacted fill) prior to construction of the foundation to provide a working surface. 8.1.4 Temporary Excavations We recommend that trenches and excavations be designed and constructed in accordance with Occupational Safety and Health Administration (OSHA) regulations. These regulations provide sloping and shoring design parameters for trenches and other excavations up to 20 feet deep based on the soil types encountered. Excavations over 20 feet deep should be Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 10 designed by the Contractor’s engineer based on site-specific geotechnical analyses. For planning purposes, we recommend that the following OSHA soil classifications be used: Fill Type C Alluvium, Santiago Formation Type B Upon making the excavations, the soil/rock classifications and excavation performance should be evaluated in the field by Ninyo & Moore in accordance with OSHA regulations. Temporary excavations should be constructed in accordance with OSHA recommendations. For trench or other excavations, OSHA requirements regarding personnel safety should be met by using appropriate shoring (including trench boxes) or by laying back the slopes no steeper than 1.5:1 (horizontal to vertical) in fill and 1:1 in Alluvium and Santiago Formation. Temporary excavations that encounter seepage may need shoring or may be stabilized by placing sandbags or gravel along the base of the seepage zone. Excavations encountering seepage should be evaluated on a case-by-case basis. Wet soils may be subject to pumping under heavy equipment loads. On-site safety of personnel is the responsibility of the contractor. 8.1.5 Shoring and Braced Excavations We anticipate that shoring systems will be installed for the site excavations. Shoring systems will be constructed through fill and alluvial materials. The shoring system should be designed using the lateral earth pressures shown on Figure 6 for cantilevered shoring and Figure 7 for braced shoring. The recommended design pressures are based on the assumptions that the shoring system is constructed without raising the ground surface elevation behind the shoring, that there are no surcharge loads, such as soil stockpiles and construction materials, that no loads act above a 1:1 plane extending up and back from the base of the sheet pile system, and that the shored excavations do not extend deeper than 20 feet. The contractor should include the effect of any surcharge loads on the lateral pressures against the sheet pile wall. Settlement of the ground surface may occur behind the shoring wall during excavation. The amount of settlement depends heavily on the type of shoring system, the shoring contractor’s workmanship, and soil conditions. We recommend that structures/improvements in the vicinity of the planned shoring installation be reviewed with regard to foundation support and tolerance to settlement. To reduce the potential for distress to adjacent improvements, we recommend that the shoring system be designed to reduce the ground settlement behind the shoring system to ½-inch or less. Possible causes Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 11 of settlement that should be addressed include settlement during shoring installation, excavations, construction vibrations, dewatering, and removal of the support system. The contractor should retain a qualified and experienced engineer to design the shoring system, evaluate the adequacy of these parameters and provide modifications for the design. Shoring plans should be reviewed by the design engineer. We recommend that the contractor take appropriate measures to protect workers. OSHA requirements pertaining to worker safety should be observed. 8.1.6 Construction Dewatering During our subsurface exploration, groundwater was encountered at approximately 12 feet bgs in close proximity of the proposed lift station location. Results of our laboratory testing suggest that the static groundwater level could be at depths of 5 feet or less. As previously discussed, fluctuations in the groundwater levels may occur at the site. Dewatering measures during excavation operations (including those for the lift station and associated vaults and utility trenches) should be prepared by the contractor’s engineer and reviewed by the design engineer. Considerations for construction dewatering should include anticipated drawdown, piping of soils, volume of pumping, potential for settlement, and groundwater discharge. As such, it may be prudent to photo-document structures and settlement sensitive improvements that are adjacent to the area of proposed construction prior to dewatering. Disposal of groundwater should be performed in accordance with guidelines of the Regional Water Quality Control Board (RWQCB). 8.1.7 Mitigation of Unstable Excavation Bottoms We anticipate that some of the bottoms of the excavations will be below the groundwater and will be unstable. In general, unstable bottom conditions may be mitigated by overexcavating the excavation bottom to suitable depths (as evaluated in the field by Ninyo & Moore’s representative) and replacing with gravel wrapped with a geosynthetic filter fabric. Specific recommendations for stabilizing excavation bottoms should be based on evaluation in the field by Ninyo & Moore at the time of construction. 8.1.8 Materials for Fill Onsite or import soils with an organic content of less than approximately 3 percent by volume (or 1 percent by weight) are considered suitable for reuse as fill. Fill material should generally not contain rocks or lumps over approximately 3 inches, and generally not more Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 12 than approximately 30 percent larger than ¾-inch. Utility trench backfill material should not contain rocks or lumps over approximately 3 inches in general. Soils classified as silts or clays should not be used for backfill in the pipe zone. Larger chunks, if generated during excavation, may be broken into acceptably sized pieces or disposed of off site. Imported fill materials should generally be granular soils with very low to low expansion potential (i.e., an expansion index of 50 or less as evaluated by ASTM D 4829). Import material should also be non-corrosive in accordance with the Caltrans (2018) corrosion guidelines. Based on the Caltrans (2018) corrosion criteria, a project site is classified as corrosive if one or more of the following conditions exist for the representative soil samples retrieved from the site: chloride concentration of 500 ppm or greater, soluble sulfate concentration of 1,500 ppm or greater, electrical resistivity of 1,100 ohm-centimeters or less, and a pH of 5.5 or less. Materials for use as fill should be evaluated by Ninyo & Moore’s representative prior to filling or importing. We recommend that materials proposed for use as import fill be evaluated from a contractor’s stockpile rather than in-place materials. 8.1.9 Compacted Fill Prior to placement of compacted fill, the contractor should request an evaluation of the exposed ground surface by Ninyo & Moore. Unless otherwise recommended, the exposed ground surface should then be scarified to a depth of approximately 6 inches and watered or dried, as needed, to achieve moisture contents generally at or slightly above the optimum moisture content. The scarified materials should then be moisture conditioned to generally above the laboratory optimum moisture content and compacted to a relative compaction of 90 percent as evaluated in accordance with ASTM D 1557. The evaluation of compaction by the geotechnical consultant should not be considered to preclude any requirements for observation or approval by governing agencies. It is the contractor's responsibility to notify this office and the appropriate governing agency when project areas are ready for observation, and to provide reasonable time for that review. Fill materials should be moisture conditioned (watered or dried) to generally at or slightly above the laboratory optimum moisture content prior to placement. The optimum moisture content will vary with material type and other factors. Moisture conditioning of fill soils should be generally consistent within the soil mass. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 13 Prior to placement of additional compacted fill material following a delay in the grading operations, the exposed surface of previously compacted fill should be prepared to receive fill. Preparation may include scarification, moisture conditioning, and recompaction. Compacted fill placed should be placed in horizontal lifts of approximately 8 inches in loose thickness. Prior to compaction, each lift placed within the proposed equipment pad area should be watered or dried as needed to achieve a moisture content generally above the laboratory optimum, mixed, and then compacted by mechanical methods to a relative compaction of 95 percent as evaluated by ASTM D 1557. Fill placed in other areas of the site should be compacted by mechanical methods to a relative compaction of 90 percent as evaluated by ASTM D 1557. Successive lifts should be treated in a like manner until the desired finished grades are achieved. 8.1.10 Lateral Pressures for Thrust Blocks Thrust restraint for buried pipelines may be achieved by transferring the thrust force to the soil outside the pipe through a thrust block. Thrust blocks may be designed using the lateral passive earth pressures presented on Figure 8. Thrust blocks should be backfilled with granular backfill material, and compacted in accordance with recommendations presented in this report. 8.1.11 Pipe Bedding and Modulus of Soil Reaction (E’) We recommend that new pipelines, where constructed in open excavations, be supported on 6 or more inches of granular bedding material overlying prepared subgrade in accordance with the recommendations presented in Section 8.1.3. Granular pipe bedding should be provided to distribute vertical loads around the pipe. Bedding material and compaction requirements should be in accordance with this report. Pipe bedding typically consists of graded aggregate with a coefficient of uniformity of three or greater. The modulus of soil reaction (E’) is used to characterize the stiffness of soil backfill placed at the sides of buried flexible pipes for the purpose of evaluating deflection caused by the weight of the backfill over the pipe (Hartley and Duncan, 1987). A soil reaction modulus of 1,200 pounds per square inch (psi) may be used for an excavation depth of up to approximately 5 feet when backfilled with granular soil compacted to a relative compaction of 90 percent as evaluated by the ASTM D 1557. A soil reaction modulus of 1,800 psi may be used for trenches deeper than 5 feet. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 14 If on site clayey soils are utilized for pipe backfill, a soil reaction modulus of 1,000 psi may be used for an excavation depth of up to approximately 5 feet. A soil reaction modulus of 1,400 psi may be used for trenches deeper than 5 feet that are backfilled with on site clayey soils. 8.1.12 Pipe Zone Backfill The pipe zone backfill should be placed on top of the pipe bedding material and extend to 1 foot or more above the top of the pipe in accordance with the recent edition of the Standard Specifications for Public Works Construction (“Greenbook”). Pipe zone backfill should have a Sand Equivalent (SE) of 30 or greater, and be placed around the sides and top of the pipe. Special care should be taken not to allow voids beneath and around the pipe. Compaction of the pipe zone backfill should proceed up both sides of the pipe. It has been our experience that the voids within a crushed rock material are sufficiently large to allow fines to migrate into the voids, thereby creating the potential for sinkholes and depressions to develop at the ground surface. If open-graded gravel is utilized as pipe zone backfill, this material should be wrapped with a geosynthetic filter fabric. 8.1.13 Utility Trench Zone Backfill Based on our subsurface evaluation, the on-site earth materials should be generally suitable for re-use as trench backfill provided they are free of organic material, clay lumps, debris, and rocks greater than approximately 3 inches in diameter. Fill should be moisture- conditioned to generally above the laboratory optimum. Trench backfill should be compacted to 90 percent of its modified Proctor density as evaluated by ASTM D 1557 except for the upper 12 inches of the backfill in pavement or flatwork areas that should be compacted to 95 percent of its modified Proctor density as evaluated by ASTM D 1557. Lift thickness for backfill will depend on the type of compaction equipment utilized, but fill should generally be placed in lifts not exceeding 8 inches in loose thickness. Special care should be exercised to avoid damaging the pipe during compaction of the backfill. 8.1.14 Drainage Proper surface drainage is imperative for satisfactory site performance. Positive drainage should be provided and maintained to direct surface water away from the new improvements. Positive drainage is defined as a slope of 2 percent or more over a distance of 5 feet away from the foundations and tops of slopes. Runoff should then be directed by Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 15 the use of swales or pipes into a collective drainage system. Surface waters should not be allowed to pond adjacent to footings or pavements. 8.2 Seismic Design Parameters Design of the proposed improvements should be performed in accordance with the requirements of governing jurisdictions and applicable building codes. Table 1 presents the site- specific spectral response acceleration parameters in accordance with the CBC (2019) guidelines. Table 1 – 2019 California Building Code Seismic Design Criteria Site Coefficients and Spectral Response Acceleration Parameters Values Site Class D Mapped Spectral Response Acceleration at 0.2-second Period, Ss 0.959g Mapped Spectral Response Acceleration at 1.0-second Period, S1 0.350g Site-Specific Spectral Response Acceleration at 0.2-second Period, SMS 1.117g Site-Specific Spectral Response Acceleration at 1.0-second Period, SM1 0.700g Site-Specific Design Spectral Response Acceleration at 0.2-second Period, SDS 0.744g Site-Specific Design Spectral Response Acceleration at 1.0-second Period, SD1 0.467g Site-Specific Maximum Considered Earthquake Geometric Mean (MCEG) Peak Ground Acceleration, PGAM 0.513g 8.3 Foundations Based on our understanding of the project, we are providing the following mat foundation recommendations for the surge tank. Foundations should be designed in accordance with structural considerations and the following recommendations. In addition, requirements of the appropriate governing jurisdictions and applicable building codes should be considered in the design of the structures. 8.3.1 Mat Foundations An allowable bearing pressure of 1,000 pounds per square foot (psf) may be assumed for mat foundations bearing on crushed rock/lean concrete base layer underlain by competent alluvium or engineered fill, in accordance with Section 8.1.3. This allowable bearing capacity may be increased by one-third when considering loads of a short duration such as wind or seismic forces. Thickness and reinforcement of the mat foundation should be in accordance with the recommendations of the project structural engineer. Mat foundations typically experience some deflection due to loads placed on the mat and the reaction of the soils underlying the mat. A design coefficient of subgrade reaction, Kv1, of 125 pounds per cubic inch may be used for evaluating such deflections at the subject sites. This value is based on a unit square-foot area and should be adjusted for the planned Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 16 mat size. The coefficient of subgrade reaction Kb for a mat of specific width may be evaluated using the following equation: Kb = Kv1[(b+1)/2b]2 where b is the width of the foundation in feet. 8.3.2 Lateral Resistance For resistance of footings to lateral loads, we recommend an allowable passive pressure that can be evaluated in accordance with the following equation: Pp = 63D + 800psf Where, D is the footing embedment in feet The above value assumes that the ground is horizontal for a distance of 10 feet, or three times the height generating the passive pressure, whichever is greater. We recommend that the upper 1 foot of soil not protected by pavement or a concrete slab be neglected when calculating passive resistance. For frictional resistance to lateral loads, we recommend a coefficient of friction of 0.20 be used between soil and concrete. The allowable lateral resistance can be taken as the sum of the frictional resistance and passive resistance provided the passive resistance does not exceed one-half of the total allowable resistance. The passive resistance values may be increased by one-third when considering loads of short duration such as wind or seismic forces. 8.3.3 Static Settlement We estimate that the proposed structures, designed and constructed as recommended herein, will undergo total settlement on the order of 1 inch. Differential settlement on the order of ½ inch over a horizontal span of 30 feet should be expected. 8.4 Underground Structures Underground structures may be designed for lateral pressures represented by the pressure diagram on Figure 9. For preliminary design purposes, we recommend that the groundwater level be assumed at an elevation of 96 MSL for evaluation of lateral pressures and calculating the factor of safety against uplift. It is recommended that the exterior of underground walls, and Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 17 horizontal and vertical construction joints be waterproofed, as indicated by the project civil engineer and/or architect. For pipe wall penetrations into the lift station, vaults, and other structures, standard “water-tight” penetration design should be utilized. To reduce the potential for relative pipe to wall differential settlement, which could cause pipe shearing, we recommend that a pipe joint be located close to the exterior of the wall. The type of joint should be such that minor relative movement can be accommodated without distress. 8.5 Uplift and Special Design Considerations We recommend that the underground structures be designed to resist hydrostatic uplift in accordance with Figure 9. Alternative design measures for resisting the anticipated uplift pressure could include installation of vertical anchors, increasing mass by constructing a thicker concrete mat foundation, or extending the foundation a selected distance outside the exterior walls of the lift station/vaults (flanges). The resistance to uplift may then be taken as the sum of the weight of the structure and the weight of the soil wedge within the zone of influence of the flanges shown on Figure 10. 8.6 Concrete Flatwork Exterior concrete flatwork should be 4 inches in thickness and should be reinforced with No. 3 reinforcing bars placed at 24 inches on-center both ways. No vapor retarder is needed for exterior flatwork. To reduce the potential manifestation of distress to exterior concrete flatwork due to movement of the underlying soil, we recommend that such flatwork be installed with crack-control joints at appropriate spacing as designed by the structural engineer. The subgrade soils should be scarified to a depth of 8 inches, moisture conditioned to generally above the laboratory optimum moisture content, and compacted to 90 percent of its modified Proctor density as evaluated by ASTM D 1557. Positive drainage should be established and maintained adjacent to flatwork. 8.7 Corrosivity Laboratory testing was performed on a representative sample of the near-surface soil to evaluate soil pH, electrical resistivity, water-soluble chloride content, and water-soluble sulfate content. The soil pH and electrical resistivity tests were performed in general accordance with California Test Method (CT) 643. Chloride content tests were performed in general accordance with CT 422. Sulfate testing was performed in general accordance with CT 417. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 18 The soil pH was measured to be 7.8 and the electrical resistivity was measured to be approximately 450 ohm-centimeters (ohm-cm). The chloride content of the samples was measured to be approximately 210 ppm. The sulfate content of the tested samples was noted to be 0.094 percent (940 ppm). Based on the laboratory test results and California Department of Transportation (2018) corrosion criteria, the soils at the project site are classified as corrosive, which is defined as having earth materials with more than 500 ppm chlorides, more than 0.15 percent sulfates (i.e., 1,500 ppm), a pH of less than 5.5, and/or an electrical resistivity of less than 1,100 ohm-cm. 8.8 Concrete Concrete in contact with soil or water that contains high concentrations of water-soluble sulfates can be subject to premature chemical and/or physical deterioration. As noted, the soil sample tested in this evaluation indicated a water-soluble sulfate content of 0.094 percent by weight (i.e., about 940 ppm). Based on the American Concrete Institute (ACI) 318 criteria, the potential for sulfate attack is negligible for soils with sulfate contents ranging from about 0.0 percent to 0.10 percent by weight (i.e. 0 to 1,000 ppm). However, due to the potential variability of site soils, and the presence of groundwater, consideration should be given to using Type V or Type II/V cement and concrete with a water-cement ratio no higher than 0.45 by weight for normal weight aggregate concrete and a 28-day compressive strength of 4,500 pounds per square inch (psi) or more for the project. We further recommend that concrete cover over reinforcing steel for slabs-on-grade and foundations be in accordance with CBC 1907.7. The structural engineer should be consulted for additional concrete specifications. 8.9 Preliminary Pavement Recommendations For preliminary design purposes, we have assumed traffic index (TI) values of 5, 6, and 7 for our initial evaluation of pavement structural sections at the site. If traffic loads are different from those assumed herein, the pavement design should be re-evaluated. Actual pavement recommendations should be based on R-value tests performed on bulk samples of the soils exposed at the finished subgrade elevations once grading operations have been performed. Based on the results of our previous laboratory testing and experience with the on-site soils, we have used a design R-value of 9 for the preliminary design of flexible pavements at the project site. As noted above, actual pavement recommendations should be based on R-value tests performed on bulk samples of the soils exposed at the finished subgrade elevations following grading operations. We recommend that the geotechnical consultant re-evaluate the pavement design at the time of construction. The recommended preliminary pavement sections are as follows: Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 19 Table 2 – Preliminary Flexible Pavement Recommendations Traffic Index Design R-Value Asphalt Concrete (in) Class 2 Aggregate Base (in) 5 9 3.0 9.0 6 9 3.0 13.0 7 9 4.0 14.5 We recommend that the upper 12 inches of the subgrade, and aggregate base materials be compacted to a relative compaction of 95 percent relative density as evaluated by the current version of ASTM D 1557. If traffic loads are different from those assumed, the pavement design should be re-evaluated. Where rigid pavement sections are proposed, we recommend a 6-inch thickness of Portland cement concrete underlain by 4 inches of compacted aggregate base. We recommend that the Portland cement concrete have a 600 pounds per square inch (psi) flexural strength and that it be reinforced with No. 3 bars that are placed 18 inches on center (both ways). The rigid pavement and aggregate base should be placed on compacted subgrade that is prepared in accordance with the recommendations presented above. 9 CONSTRUCTION OBSERVATION The recommendations provided in this report are based on our understanding of the proposed project and on our evaluation of the data collected based on subsurface conditions disclosed by widely spaced exploratory excavations. It is imperative that the interpolated subsurface conditions be checked by a qualified person during construction. Observation of foundation excavations and observation and testing of compacted fill and backfill should be performed by a qualified person during construction. In addition, the project plans and specifications should be reviewed to check for conformance with the recommendations of this report prior to construction. It should be noted that, upon review of these documents, some recommendations presented in this report might be revised or modified. During construction we recommend that the duties of the geotechnical consultant include, but not be limited to: • Observing excavation bottoms and the placement and compaction of fill, including trench backfill. • Evaluating imported materials prior to their use as fill, if used. • Performing field tests to evaluate fill compaction. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 20 • Providing continuous observations during earthwork operations to evaluate the presence and activity level of exposed faults. • Observing foundation excavations for bearing materials and cleaning prior to placement of reinforcing steel or concrete. 10 LIMITATIONS The field evaluation, laboratory testing, and geotechnical analyses presented in this geotechnical report have been conducted in general accordance with current practice and the standard of care exercised by geotechnical consultants performing similar tasks in the project area. No warranty, expressed or implied, is made regarding the conclusions, recommendations, and opinions presented in this report. There is no evaluation detailed enough to reveal every subsurface condition. Variations may exist and conditions not observed or described in this report may be encountered during construction. Uncertainties relative to subsurface conditions can be reduced through additional subsurface exploration. Additional subsurface evaluation will be performed upon request. This document is intended to be used only in its entirety. No portion of the document, by itself, is designed to completely represent any aspect of the project described herein. Ninyo & Moore should be contacted if the reader requires additional information or has questions regarding the content, interpretations presented, or completeness of this document. This report is intended for design purposes only. It does not provide sufficient data to prepare an accurate bid by contractors. It is suggested that the bidders and their geotechnical consultant perform an independent evaluation of the subsurface conditions in the project areas. The independent evaluations may include, but not be limited to, review of other geotechnical reports prepared for the adjacent areas, site reconnaissance, and additional exploration and laboratory testing. Our conclusions, recommendations, and opinions are based on an analysis of the observed site conditions. If geotechnical conditions different from those described in this report are encountered, our office should be notified, and additional recommendations, if warranted, will be provided upon request. It should be understood that the conditions of a site could change with time as a result of natural processes or the activities of man at the subject site or nearby sites. In addition, changes to the applicable laws, regulations, codes, and standards of practice may occur due to government action or the broadening of knowledge. The findings of this report may, therefore, be invalidated over time, in part or in whole, by changes over which Ninyo & Moore has no control. This report is intended exclusively for use by the client. Any use or reuse of the findings, conclusions, and/or recommendations of this report by parties other than the client is undertaken at said parties’ sole risk. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 21 11 REFERENCES Abrahamson, N.A., Silva, W.J., and Kamai, R., 2014, Summary of the ASK 14 ground motion relation for active crustal regions, Earthquake Spectra Volume 30, pp. 1025-1055. American Concrete Institute (ACI), 2019, ACI 318 Building Code Requirements for Structural Concrete and Commentary. American Society of Civil Engineers (ASCE), 2017, Minimum Design Loads for Buildings and Other Structures, ASCE 7-16. Atik, Linda L., and Sitar, N., 2010, Seismic Earth Pressures on Cantilever Retaining Structures, ASCE Journal of Geotechnical and Geoenvironmental Engineering, Vol. 136, No. 10, October 1. Boore, D.M., Stewart, J.P., Seyhan, E., and Atkinson, G.M., 2014, NGA-West2 Equations for Predicting PGA, PGV, and 5% Damped PSA for Shallow Crustal Earthquakes, Earthquake Spectra, Vol. 30, No. 3, pp. 1057-1085: dated August. Bray, J.D., and Sancio, R.B., 2006, Assessment of the Liquefaction Susceptibility of Fine Grained Soils: American Society of Civil Engineers, Journal of the Geotechnical and Geoenvironmental Engineering, v. 132, n. 9, p. 1165-1177. Brandenberg, S.J., Bellana, N., and Shantz, T., (2010), Shear Wave Velocity as Function of SPT Penetration Resistance and Vertical Effective Stress at California Bridge Sites, Soil Dynamics and Earthquake Engineering, 30, pp. 1026-1035 Building News, 2018, “Greenbook”, Standard Specification for Public Works Construction: BNI Publications. Building Seismic Safety Council, 2009, National Earthquake Hazards Reduction Program (NEHRP) Recommended Seismic Provisions for New Buildings and Other Structures (FEMA P-750). California Building Standards Commission, 2019, California Building Code (CBC): California Code of Regulations, Title 24, Part 2, Volumes 1 and 2. California Department of Transportation (Caltrans), 2018, Corrosion Guidelines (Version 3.0), Division of Engineering and Testing Services, Corrosion Technology Branch: dated March. California Department of Transportation (Caltrans), 2020, ARS Online Web Tool, version 2.3.09, http://dap3.dot.ca.gov/ARS_Online/. California Geological Survey, State of California, 2008, Guidelines for Evaluating and Mitigating Seismic Hazards in California, CDMG Special Publication 117A. Campbell, K.W., and Bozorgnia, Y., 2014, NGA-West2 Ground Motion Model for the Average Horizontal Components of PGA, PGV, and 5% Damped Linear Acceleration Response Spectra, Earthquake Spectra, Vol. 30, No. 3, pp. 1087-1115: dated August. Chiou, B. S.-J., and Youngs, R.R., 2014, Update of the Chiou and Youngs NGA Model for the Average Horizontal Component of Peak Ground Motion and Response Spectra, Earthquake Spectra, August 2014, Vol. 30, No. 3: dated August. Geotracker, 2020, www.geotracker.waterboards.ca.gov: accessed in January. Google Inc., 2020, www.googleearth.com: accessed in January. Harden, D.R., 2004, California Geology 2nd Edition: Prentice Hall, Inc. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 22 Hart, E.W., and Bryant, W.A., 2007, Fault-Rupture Hazard Zones in California, Alquist-Priolo Earthquake Fault Zoning Act with Index to Earthquake Fault Zone Maps: California Department of Conservation, Division of Mines and Geology, Special Publication 42, with Supplement 1 added in 2012, Supplement 2 added in 2014, Supplement 3 added in 2015, and Supplement 4 added in 2016. Hartley, J.D., and Duncan, J.M., 1987, E’ and Its Variation with Depth: American Society of Civil Engineers (ASCE), Journal of Transportation Engineering, Vol. 113, No. 5: dated September. Jennings, C.W., 2010, Fault Activity Map of California and Adjacent Areas: California Geological Survey, California Geological Map Series, Map No. 6. Kennedy, M.P., and Tan, S. S., 2008 Geologic Map of the Oceanside 30’ X 60’ Quadrangle, California Regional Geologic Map Series, Scale 1:100,000. Ninyo & Moore, 2006, Geotechnical Evaluation, Alga Norte Community Park, Carlsbad, California, Project No. 104600002: dated June 14. Ninyo & Moore, 2015, Geotechnical Evaluation, Emergency Storage Basin, Poinsettia Lift Station, Carlsbad, California, Project No. 10754409: dated June 10. Ninyo & Moore, 2019, Proposal for Update Geotechnical Evaluation, Poinsettia Lift Station, Carlsbad, California: dated December 6. Norris, R.M. and Webb, R.W., 1990, Geology of California, Second Edition: John Wiley & Sons, Inc. OpenSHA and the University of Southern California, 2010, Hazard Curve Application, Version 1.3.2. Seyhan, E, 2014, Weighted Average 2014 NGA West-2 GMPE, Pacific Earthquake Engineering Research Center. Southern California Earthquake Data Center, 2005, SCEC Community Velocity Model, Version 11.9.0. Structural Engineering Association of California (SEAOC), Office of Statewide Health Planning and Development (OSHPD), 2020, U.S. Seismic Design Maps website, https://seismicmaps.org/: accessed in January. Tan, S. S., 1995, Landslide Hazards in the Northern Part of the San Diego Metropolitan Area, San Diego County, California, California Division of Mines and Geology Open-File Report 95-04, scale 1:24,000. United States Department of Agriculture (USDA), 1953, Flight AXN-8M, Numbers 19 and 20, Scale 1:20,000: dated April 11. United States Geological Survey (USGS), 2018 Topographic Map, 7.5-minute Encinitas Quadrangle, San Diego County, California United States Geological Survey (USGS), 2019a, 2008 National Seismic Hazard Maps – Fault Parameters Database, World Wide Web, https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/query_main.cfm. United States Geological Survey (USGS) and Southern California Earthquake Center (SCEC), 2019b, Open Seismic Hazard Analysis, http://www.opensha.org/. United States Geological Survey, 2019c, Unified Hazard Tool; https://earthquake.usgs.gov/hazards/interactive/. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 23 United States Geological Survey, 2019d, Slope Based Vs30 Map Viewer; https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id=8ac19bc334f747e486550f32837578e1. Wills, C.J., and Clahan, L.B., 2006, Developing a Map of Geologically Defined Site-Condition Categories for California, Bulletin of the Seismological Society of America, v. 96, no. 4A, p. 1483–1501. Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 Appendix A Photographic Documentation FIGURES SITE "!o 0 1,500 3,000 FEET MAP INDEX San DiegoCounty 1_107544015_SL.mxd 1/13/2020 AOBNOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE. | SOURCE: ESRI WORLD TOPO, 2017 SITE LOCATIONFIGURE 1 107544015 | 1/20 POINSETTIA LIFT STATIONCARLSBAD, CALIFORNIA Las 1mas D1 N1c:o6<J <2 ~ 11 c" i!:! lS.SIJ Rd d Ave Jfrmmer C' Oriol Cl c Q Geotechnical & Environmental Sciences Consultants AIJ Nort rk Do woo Rd Pb1n _tt,c, Ebm.nta,-., ....,~ .B ~ ~ iii J;I C: ,p Es u r,onsr @A @A B-2 TD=35.5 B-1 TD=46.5 GEODE LANE LEGEND BORINGTD=TOTAL DEPTH IN FEET@AB-2 TD=35.5 POINSETTIA LANE 2_107544015_BL.mxd 1/23/2020 AOBNOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE. | SOURCE: AERIAL IMAGERY - ©2015 PICTOMETRY INTERNATIONAL CORP. BORING LOCATIONS POINSETTIA LIFT STATIONCARLSBAD, CALIFORNIA 107544015 | 1/20 FIGURE 2 0 60 120 FEET!o " APPROXIMATE LOCATIONOF PROPOSED SURGE TANK Geotechnical & Environmental Sciences Consultants !! SITE "MzuLEGEND REFERENCE: KENNEDY, M.P. AND TAN, S.S., CALIFORNIA GEOLOGICALSURVEY, 2008, GEOLOGIC MAP OF THE SAN DIEGO30' X 60' QUADRANGLE, CALIFORNIA 3_107544015_G.mxd 1/13/2020 AOBGEOLOGY FIGURE 3 !o 0 2,000 4,000 FEET 107544015 | 1/20 POINSETTIA LIFT STATIONCARLSBAD, CALIFORNIA 70 10 33 Young alluvial flood-plain deposits (Holocene and late Pleistocene) Very old paralic deposits, undivided (middle to early Pleistocene) 1a,op1e>11 I Units 10-11 Santiago Formation (middle Eocene) Metasedimentary and metavolcanic rocks, undivided (Mesozoic) _1__.!:L_ Fault -Solid where accurately located; dashed where approximately located; dotted where concealed. U = upthrown block, D = downthrown block. Arrow and number indicate direction and angle of dip of fault plane. D Landslide - Arrows indicate principal direction of movement. Queried where existence is questionable. Strike and dip of beds Geotechnical & Environmental Sciences Consultants M E X I C OUSAP a c i f i c O c e a n NEVADA CALIFORNIA SAN JACINTO ELSINORE I M P E RIA L WHITTIER NE W PORT-INGLEWOOD C O R O N A D O B A N K S A N D IE G O T R O U G H SAN CLEMENTE S A N T A C RUZ-SANTACATALINARIDGE P A L O S VERDES OF F S H O R E Z O N E OF D E F O R M A T I O N G ARLOCKCLEARWATE RS A N GABRIEL SIERRAMADRE BANNING MISSION CREEK BLAC K W ATE RHARPER LOCKHART LEN W O O D CAMPROCK CALIC O LUDLOW PI S GAHBULLION M O U N T AIN JOH NSO N VALLEY EMERSON P IN T O M O UNTAINMANIX MIRAGEVALLEY NORTHHELENDALE FRONTAL CHINO S A N J OS ECUCAMON GA MALIBU COA ST S A N T A MONICA SANCAYETANO SANTASUSANASANTAROSA N O R T H R ID G E CHA RN O CK S A W P ITCAN Y O N SUPERSTITION HILLS R O S E C A NYONPINEMOUNTAIN W HITEW O LFSAN A N D R E A S F A U L T Z O N EPLEITOWHEELER POSOCREEK BLUE CUT SALTON CREEK SA N A N D R E A S F A U L T Z O N E COYOTE CREEK CLARK GLEN IVY EARTHQUAKE VALLEY ELMORERANCHLAGUNA SALADA BRAW LEY S E I SM I C ZONE San Bernardino County Kern County Riverside County San Diego County Imperial County Los Angeles County Inyo CountyTulare County Ventura County Orange County CALIFORNIA HOLOCENE ACTIVE CALIFORNIA FAULT ACTIVITY HISTORICALLY ACTIVE LATE QUATERNARY (POTENTIALLY ACTIVE)STATE/COUNTY BOUNDARY QUATERNARY (POTENTIALLY ACTIVE) SOURCE: U.S. GEOLOGICAL SURVEY AND CALIFORNIA GEOLOGICAL SURVEY, 2006,QUATERNARY FAULT AND FOLD DATABASE FOR THE UNITED STATES. SITE "4_107544015_FL.mxd 1/13/2020 AOBNOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE. FAULT LOCATIONS FIGURE 4 !o 0 30 60 MILES LEGEND ! 107544015 | 1/20 POINSETTIA LIFT STATIONCARLSBAD, CALIFORNIA -=-.,,._ ' . --~ ' " ... --==-~ -..,. '\ \ '\. '1-~, ' ~-~»,,,._ ~~ \ ', ~--.. ,~,) JVin9o&JV\Oore Geotechnical & Environmental Sciences Consultants ---- -- SDS =gSD1 =g SMS =gSM1 =g g NOTES: 1 exceedance in 50 years in the maximum direction using the Chiou & Youngs (2014), Campbell & Bozorgnia (2014), Boore et al. (2014), and Abrahamson et al. (201 attenuation relationships and the risk coefficients. 2 The deterministic ground motion spectral response accelerations are for the 84th percentile of the geometric mean values in the maximum direction using the Chiou Youngs (2014), Campbell & Bozorgnia (2014), Boore et al. (2014), and Abrahamson et al. (2014) attenuation relationships for deep soil sites considering a Mw 7.0 e on the Rose Canyon Fault fault zone located 11.34 kilometers from the site. It conforms with the lower bound limit per ASCE 7-16 Section 21.2.2. 3 The Site-Specific MCER Response Spectrum is the lesser of spectral ordinates of deterministic and probabilistic accelerations at each period per ASCE 7-16 Section 21.2.3. The Site-Specific Design Response Spectrum conforms with lower bound limit per ASCE 7-16 Section 21.3. 4 The Mapped Design MCER Response Spectrum is computed from mapped spectral ordinates modified for Site Class D (stiff soil profile) per ASCE 7-16 Section 11. It is presented for the sake of comparison. 0.827 0.093 7.500 0.062 0.400 0.784 0.250 0.823 10.000 0.0370.300 0.724 0.571 0.467 0.311 2.000 4.000 0.233 0.156 0.117 3.000 0.536 0.633 0.748 0.801 0.500 0.750 1.000 1.500 5.000 0.075 0.100 0.150 0.200 0.339 0.341 0.358 0.422 0.010 0.020 0.030 0.050 PERIOD (seconds) SITE-SPECIFIC DESIGN RESPONSE SPECTRUM Sa (g) SITE-SPECIFIC MCER RESPONSE SPECTRUM Sa (g) PERIOD (seconds) SITE-SPECIFIC DESIGN RESPONSE SPECTRUM Sa (g) 0.836 0.632 0.384 The probabilistic ground motion spectral response accelerations are based on the risk-targeted Maximum Considered Earthquake (MCE R) having a 2% 1.235 1.241 1.176 SITE-SPECIFIC MCER RESPONSE SPECTRUM Sa (g) 0.508 0.511 0.537 0.633 0.804 1.087 0.744 0.262 0.156 0.108 0.082 0.046 0.029 0.950 1.121 1.201 0.467 1.117 0.700 PGAM =0.513 0.0 0.5 1.0 1.5 012345678910SPECTRAL ACCELERATION, Sa (g)PERIOD, T (seconds) Mapped Design MCE Response Spectrum Site-Specific Design Response Spectrum Site-Specific MCE Response SpectrumR R FIGURE 5 ACCELERATION RESPONSE SPECTRA POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 | 1/20 Site-Specific Response ASCE 7-16_Risk Category III -------· ,, I \ ' \ I I ' I ' ' r \ I \ ·~ I \ I \ ' \ \ \ ~ '--------·--r-----... ------------ Gaotacmlcal & Envlronm1ntal S~l11nce1 Consultanb pP D H Pa NOTES: ACTIVE LATERAL EARTH PRESSURE, P P = 50 H psf; 1. 4. P = 63 D + 800 psf PASSIVE LATERAL EARTH PRESSURE, P 6.H, h AND D ARE IN FEET a a p p SHORING Ps 2. s sP = 120 psf CONSTRUCTION TRAFFIC INDUCED SURCHARGE PRESSURE, P GROUNDWATER TABLE7. + 2 Pa1 + wP h 1 P = a2 HYDROSTATIC PRESSURE, P 3. P =62.4 (H - h) psf w w SURCHARGES FROM EXCAVATED SOIL OR CONSTRUCTION5. MATERIALS ARE NOT INCLUDED 1aP + 25 (H - h) psf FIGURE 66_107544015_D-CSBG.DWG AOBPOINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 I 1/20 Geotechnical & Environmental Sciences Consultants LATERAL EARTH PRESSURES FOR TEMPORARY CANTILEVERED SHORING BELOW GROUNDWATER P D H Pa + NOTES: APPARENT LATERAL EARTH PRESSURE, P P = 50 H psf; 1. CONSTRUCTION TRAFFIC INDUCED SURCHARGE PRESSURE, P P = 120 psf 2. 3. SURCHARGES FROM EXCAVATED SOIL OR5. CONSTRUCTION MATERIALS ARE NOT INCLUDED H/4 H/4 6. s a s a s SHORING BRACES Pp 2 + Pw h 7. 4. w wP =62.4 (H - h) psf HYDROSTATIC PRESSURE, P GROUNDWATER TABLE p p H, h AND D ARE IN FEET PASSIVE LATERAL EARTH PRESSURE, P P = 63 D + 800 psf 1 P = 25 H psfa2 1aP Geotechnical & Environmental Sciences Consultants7_107544015_D-LEP_SC.DWG AOBPOINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 I 1/20 LATERAL EARTH PRESSURES FOR BRACED EXCAVATION (STIFF CLAY) FIGURE 7 NOTES: GROUNDWATER BELOW BLOCK GROUNDWATER ABOVE BLOCK2. 1. P = 62.5p(D -d )2 2 lb/ft THRUST BLOCK d (VARIES) P Pp p D (VARIES) 3.ASSUMES BACKFILL IS CLAYEY MATERIAL 4.ASSUMES THRUST BLOCK IS ADJACENT TO COMPETENT MATERIAL 1 Pp2 pP = ( D - d )[ 62.4h + 31.3 ( D+d )+800] GROUNDWATER TABLE6. D, d AND h ARE IN FEET5. h lb/ft 800 (D -d) lb/ft+ Geotechnical & Environmental Sciences Consultants8_107544015_D-TB.DWG AOBPOINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 I 1/20 THRUST BLOCK LATERAL EARTH PRESSURE DIAGRAM FIGURE 8 NOTES: 1. GROUNDWATER TABLE 5. OR NEARBY STRUCTURES ARE NOT INCLUDED SURCHARGE PRESSURES CAUSED BY VEHICLES 3. 2 h h H UPLIFT PRESSURE 1 P DYNAMIC H/3+ WATER PRESSURE PRESSURESTATIC PRESSURE RESULTANT DYNAMIC LATERAL EARTH PRESSURE IS BASED ON A PEAK GROUND ACCELERATION OF 0.51g 6.H, h AND h ARE IN FEET12 E WP 02P UP P 01 01APPARENT LATERAL EARTH PRESSURES, P AND P02 P = 102 h psf011 1P = 102 h + 51 h psf022 2. wP = 62.4 h psf2 WATER PRESSURE, Pw 7. 4. P = 62.4 h psf2u uUPLIFT PRESSURE, P EP = 31 H psf Geotechnical & Environmental Sciences Consultants9_107544015_D-LEP_US.DWG AOBPOINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 I 1/20 LATERAL EARTH PRESSURES FOR UNDERGROUND STRUCTURES FIGURE 9 NOTES: 1. = 125 pcf ABOVE GROUNDWATER TABLE UNIT WEIGHT OF SOILS, OR = 62.6 pcf BELOW GROUNDWATER TABLE SOIL WEDGE A Z P 20° h1 2h H RESISTANCE TO UPLIFT = WEIGHT OF STRUCTURE + WEIGHT OF SOIL WEDGE A UPLIFT PRESSURE, P2. 2 b b 3.H, Z, h AND h ARE IN FEET 1 2 4.GROUNDWATER TABLE u P = 62.4 h psf u u Geotechnical & Environmental Sciences Consultants10_107544015_D-UR.DWG AOBPOINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 I 1/20 UPLIFT RESISTANCE DIAGRAM FOR UNDERGROUND STRUCTURES FIGURE 10 Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 APPENDIX A Boring Logs Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 APPENDIX A BORING LOGS Field Procedure for the Collection of Disturbed Samples Disturbed soil samples were obtained in the field using the following methods. Bulk Samples Bulk samples of representative earth materials were obtained from the exploratory excavations. The samples were bagged and transported to the laboratory for testing. The Standard Penetration Test (SPT) Sampler Disturbed drive samples of earth materials were obtained by means of a Standard Penetration Test sampler. The sampler is composed of a split barrel with an external diameter of 2 inches and an unlined internal diameter of 1⅜ inches. The sampler was driven into the ground 12 to 18 inches with a 140-pound hammer free-falling from a height of 30 inches in general accordance with ASTM D 1586. The blow counts were recorded for every 6 inches of penetration; the blow counts reported on the logs are those for the last 12 inches of penetration. Soil samples were observed and removed from the sampler, bagged, sealed and transported to the laboratory for testing. Field Procedure for the Collection of Relatively Undisturbed Samples Relatively undisturbed soil samples were obtained in the field using the following method. The Modified Split-Barrel Drive Sampler The sampler, with an external diameter of 3.0 inches, was lined with 1-inch long, thin brass rings with inside diameters of approximately 2.4 inches. The sample barrel was driven into the ground with the weight of a hammer of the drill rig in general accordance with ASTM D 3550. The driving weight was permitted to fall freely. The approximate length of the fall, the weight of the hammer, and the number of blows per foot of driving are presented on the boring logs as an index to the relative resistance of the materials sampled. The samples were removed from the sample barrel in the brass rings, sealed, and transported to the laboratory for testing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feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.BORING LOG EXPLANATION SHEET BORING LOG 20 IBORJNG lOG EXIPlJ'l\NAl!ON SH[E[El Geotechnical & Environmental Sciences Consultants 0 10 20 30 40 21 25 32 29 27 57 95 22.5 21.8 19.2 21.9 25.1 14.2 17.8 100.8 102.9 105.6 101.9 98.1 118.1 111.6 GM CL CL CH ASPHALT CONCRETE: Approximately 4 inches thick. AGGREGATE BASE: Brown, moist, dense, silty GRAVEL with sand; approximately 26 inches thick. FILL: Gray, moist, very stiff, silty CLAY. ALLUVIUM: Brown, moist, very stiff, silty CLAY. Gray. Light brown to light gray; hard; sand and scattered gravel; carbon staining. Wet. Light gray to greenish gray, wet, hard, fat CLAY. SANTIAGO FORMATION: Light brown, wet, weakly cemented, silty fine-grained SANDSTONE. Light brown, wet, moderately indurated, fine sandy SILTSTONE. FIGURE A- 1 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 |1/20DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION DATE DRILLED 5/06/15 BORING NO.B-1 GROUND ELEVATION 110' ± (MSL)SHEET 1 OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip)DROP 30" SAMPLED BY BTM LOGGED BY BTM REVIEWED BY GTF 2 Geotcchnical & Environmental Sciences Consultants 40 50 60 70 80 88/11" 50/4" 19.0 29.1 107.2 101.9 SANTIAGO FORMATION: (Continued) Light gray, wet, moderately indurated, fine sandy SILTSTONE. @ Approximately 40': Harder drilling. Total Depth = 46.5 feet. Groundwater encountered at approximately 35 feet during drilling and approximately 22 feet after drilling. Backfilled with approximately 16 cubic feet of bentonite grout and black-dyed concrete cap shortly after drilling on 5/06/15. Note: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 2 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 |1/20DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION DATE DRILLED 5/06/15 BORING NO.B-1 GROUND ELEVATION 110' ± (MSL)SHEET 2 OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip)DROP 30" SAMPLED BY BTM LOGGED BY BTM REVIEWED BY GTF 2 Geotcchnical & Environmental Sciences Consultants 0 10 20 30 40 23 29 30 30 26 50/5" 62 19.4 19.1 20.1 21.9 21.8 20.4 20.6 108.0 107.4 106.0 105.0 101.8 105.9 GM CL CL ASPHALT CONCRETE: Approximately 4 inches thick. AGGREGATE BASE: Brown, moist, dense, silty GRAVEL with sand; approximately 26 inches thick. FILL: Gray, moist, very stiff, silty CLAY. ALLUVIUM: Gray to brown, moist, hard, sandy CLAY. Wet. Greenish gray to light brown. Gray; very stiff. SANTIAGO FORMATION: Greenish gray to light brown, wet, moderately cemented, silty fine-grained SANDSTONE. @ 30': Very hard drilling. Greenish gray to light brown, wet, moderately indurated, fine sandy SILTSTONE. Total Depth = 35.5 feet Groundwater encountered at approximately 12 feet after drilling. Backfilled with approximately 12 cubic feet of bentonite grout and black-dyed concrete cap shortly after drilling on 5/06/15. Note: Groundwater may rise to a level higher than that measured in borehole due to FIGURE A- 3 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 |1/20DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION DATE DRILLED 5/06/15 BORING NO.B-2 GROUND ELEVATION 110' ± (MSL)SHEET 1 OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip)DROP 30" SAMPLED BY BTM LOGGED BY BTM REVIEWED BY GTF 2 Geotcchnical & Environmental Sciences Consultants 40 50 60 70 80 seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 4 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA 107544015 |1/20DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION DATE DRILLED 5/06/15 BORING NO.B-2 GROUND ELEVATION 110' ± (MSL)SHEET 2 OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip)DROP 30" SAMPLED BY BTM LOGGED BY BTM REVIEWED BY GTF 2 Geotcchnical & Environmental Sciences Consultants Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 3. Description 3. Description 3. Description APPENDIX B Laboratory Testing Ninyo & Moore | Poinsettia Lift Station, Carlsbad, California | 107544015 | January 24, 2020 APPENDIX B LABORATORY TESTING Classification Soils were visually and texturally classified in accordance with the Unified Soil Classification System (USCS) in general accordance with ASTM D 2488. Soil classifications are indicated on the logs of the exploratory borings in Appendix A. In-Place Moisture and Density Tests The moisture content and dry density of relatively undisturbed samples obtained from the exploratory borings were evaluated in general accordance with ASTM D 2937. The test results are presented on the logs of the exploratory borings in Appendix A. Gradation Analysis Gradation analysis tests were performed on selected representative soil samples in general accordance with ASTM D 422. The grain-size distribution curves are shown on Figures B-1 through B-4. The test results were utilized in evaluating the soil classifications in accordance with the USCS. Atterberg Limits Tests were performed on selected representative fine-grained soil samples to evaluate the liquid limit, plastic limit, and plasticity index in general accordance with ASTM D 4318. These test results were utilized to evaluate the soil classification in accordance with the Unified Soil Classification System (USCS). The test results and classifications are shown on Figure B-5. Consolidation Tests Consolidation tests were performed on a selected relatively undisturbed soil sample in general accordance with ASTM D 2435. The sample was inundated during testing to represent adverse field conditions. The percent of consolidation for each load cycle was recorded as a ratio of the amount of vertical compression to the original height of the sample. The results of the test are summarized on Figure B-6. Direct Shear Tests One direct shear test was performed on a sample in general accordance with ASTM D 3080 to evaluate the shear strength characteristics of the selected material. The sample was inundated during shearing to represent adverse field conditions. The test results are shown on Figure B-7. R-Value The resistance value, or R-value, for site soils was evaluated in general accordance with California Test (CT) 301. Samples were prepared and evaluated for exudation pressure and expansion pressure. The equilibrium R-value is reported as the lesser or more conservative of the two calculated results. The test results are shown on Figure B-8. Soil Corrosivity Tests Soil pH, and electrical resistivity tests were performed on a representative sample in general accordance with CT 643. The chloride content of the selected sample was evaluated in general accordance with CT 422. The sulfate content of the selected sample was evaluated in general accordance with CT 417. The test results are presented on Figure B-9. . I 107544015 SIEVE B-1 @ 10.0-11.5.xls Coarse Fine Coarse Medium SILT CLAY 3" 2"¾"½" ⅜"4 8 30 50 PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422 107544015 1/20 B-1 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA Fine Sample Location 100 D10 16 200 GRAVEL SAND FINES Symbol Plasticity Index Plastic Limit Liquid Limit 1½" 1" Depth (ft)D30 B-1 10.0-11.5 47 20 27 Cu -- USCS -- D60 CL------74 Passing No. 200 (%) Cc 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 0.00010.0010.010.1110100PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS U.S. STANDARD SIEVE NUMBERS HYDROMETER GRADATION TEST RESULTS PROJECT NO.DATE FIGURE I I I I I I I I -.... ·o. r---1""1~ " ~ " ~. I • I I I I I I I I I I I I I l(ln90&/(t.Oo~e 107544015 SIEVE B-1 @ 25.0-26.5.xls Coarse Fine Coarse Medium SILT CLAY 3" 2"¾"½" ⅜"4 8 30 50 PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422 -- D60 CH------80 Passing No. 200 (%) Cc Fine Sample Location 100 D10 16 B-1 25.0-26.5 56 24 32 GRAVEL SAND FINES Symbol Plasticity Index Plastic Limit Liquid Limit 1½" 1" Depth (ft)D30 200 107544015 1/20 B-2 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA Cu -- USCS 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 0.00010.0010.010.1110100PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS U.S. STANDARD SIEVE NUMBERS HYDROMETER GRADATION TEST RESULTS PROJECT NO.DATE FIGURE I I I I I I I I -~ ~r--N ~r-.. ~ ~ .. I • I I I I I I I I I I I I I l(ln90&/(t.Oo~e 107544015 SIEVE B-2 @ 5.0-6.5.xls Coarse Fine Coarse Medium SILT CLAY 3" 2"¾"½" ⅜"4 8 30 50 PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422 107544015 1/20 B-3 POINSETTIA LIFT STATION CALSBAD, CALIFORNIA Fine Sample Location 100 D10 16 200 GRAVEL SAND FINES Symbol Plasticity Index Plastic Limit Liquid Limit 1½" 1" Depth (ft)D30 B-2 5.0-6.5 38 17 21 Cu -- USCS -- D60 CL------59 Passing No. 200 (%) Cc 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 0.00010.0010.010.1110100PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS U.S. STANDARD SIEVE NUMBERS HYDROMETER GRADATION TEST RESULTS PROJECT NO.DATE FIGURE I I I I I I I I -~ l T -.. ~ ~ .. r-.... ~~ '\ N !\, • I • I I I I I I I I I I I I I l(ln90&/(t.Oo~e 107544015 SIEVE B-2 @ 15.0-16.5.xls Coarse Fine Coarse Medium SILT CLAY 3" 2"¾"½" ⅜"4 8 30 50 PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422 107544015 1/20 B-4 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA Fine Sample Location 100 D10 16 200 GRAVEL SAND FINES Symbol Plasticity Index Plastic Limit Liquid Limit 1½" 1" Depth (ft)D30 B-2 15.0-16.5 38 17 21 Cu -- USCS -- D60 CL------69 Passing No. 200 (%) Cc 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 0.00010.0010.010.1110100PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS U.S. STANDARD SIEVE NUMBERS HYDROMETER GRADATION TEST RESULTS PROJECT NO.DATE FIGURE I I I I I I I I -.,. ~ ... ... t'-,. r-... I'-N '\ ~ • I • I I I I I I I I I I I I I l(ln90&/(t.Oo~e 107544015 ATTERBERG Page 1.xls LOCATION NP - INDICATES NON-PLASTIC PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 4318 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA CL 21 CL 2117 17 CL CH CL CL CL CH No. 40 Sieve) SYMBOL 10.0-11.5 2747 (FT) DEPTH 20B-1 CLASSIFICATION 32 15.0-16.5 5.0-6.5 56 38 38 25.0-26.5 24B-1 B-2 B-2 INDEX, PI LIQUID PLASTIC PLASTICITY LIMIT, LL 107544015 1/20 B-5 USCS USCS (Entire Sample)(Fraction Finer ThanLIMIT, PL CH or OH CL or OL MH or OH ML or OLCL -ML 0 10 20 30 40 50 60 0 10 20 30 40 50 60 70 80 90 100PLASTICITY INDEX, PI LIQUID LIMIT, LL ATTERBERG LIMITS TEST RESULTS PROJECT NO.DATE FIGURE • ■ 0 / ~/ / / / / / V ■ / • / • ~ / / / / ,/ / / I / Jfin9o&l(toore 107544015 CONSOLIDATION B-2 @ 25.0-26.5.xls Seating Cycle Sample Location B-2 Loading Prior to Inundation Depth (ft.)25.0-26.5 Loading After Inundation Soil Type CL Rebound Cycle PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 2435 107544015 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA B-61/20 -4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 0.1 1.0 10.0 100.0 CONSOLIDATION IN PERCENT OF SAMPLE THICKNESS (%) EXPANSION (%)STRESS IN KIPS PER SQUARE FOOT CONSOLIDATION TEST RESULTS PROJECT NO.DATE FIGURE II. ....... ....... ,,._ --........ "'-"'-·~ "'-1L ........ ' ' ........ r--'-.... .... ........ " ........ ' ', '\. 1, '\. ' ' '\ ' ..... I'\ '"-'-" ' ' ' \ ' I\ ' \ ' \ \ ' ' \. \ ' ' . \ ' \ '\' ~. - -------• "' _ _..,__ JYln90&1V\oore 107544015 SHEAR B-1 @ 15.0-16.5.xls X 1/20 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA Ultimate15.0-16.5B-1 B-7 PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 3080 CLAY 107544015 Cohesion, c (psf) Friction Angle, φ (degrees)Soil Type CL12 12 390 CL Description Symbol Sample Location 410 Depth (ft) Shear Strength 15.0-16.5CLAYB-1 Peak 0 1000 2000 3000 4000 5000 0 1000 2000 3000 4000 5000SHEAR STRESS (PSF)NORMAL STRESS (PSF) DIRECT SHEAR TEST RESULTS PROJECT NO.DATE FIGURE -~ --..--- L-.-.-"" --0 ---____. .---,-,,,-------- • .... --- JYln9o&JYt.Oo~e 107544015 R-VALUE Page 1.xls PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 2844/CT 301 SAMPLE LOCATION SAMPLE DEPTH (FT)SOIL TYPE R-VALUE 3.0-8.0B-2 9CLAY (CL) B-8 1/20107544015 POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA R-VALUE TEST RESULTS PROJECT NO.DATE FIGURE 107544015 CORROSIVITY Page 1.xls 1 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 643 2 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 417 3 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 422 940 0.094 1/20 B-9POINSETTIA LIFT STATION CARLSBAD, CALIFORNIA B-1 3.0-8.0 7.8 CHLORIDE CONTENT 3 (ppm) pH 1SAMPLE DEPTH (FT) SAMPLE LOCATION (Ohm-cm) RESISTIVITY 1 SULFATE CONTENT 2 (%)(ppm) 210450 107544015 CORROSIVITY TEST RESULTS PROJECT NO. DATE FIGUREl(ln9o&J>f.Oo~e Ninyo & Moore | 1339 Temple Hills Drive, Laguna Beach, California | 209769001 R | April 3, 2017 5710 Ruffin Road | San Diego, California 92123 | p. 858.576.1000 SAN DIEGO | IRVINE | LOS ANGELES | FONTANA | OAKLAND | SAN FRANCISCO | SACRAMENTO SAN JOSE | PHOENIX | TUCSON | PRESCOTT | LAS VEGAS | DENVER | BROOMFIELD | HOUSTON www.ninyoandmoore.com Geotechnical & Environmental Sciences Consultants