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HomeMy WebLinkAboutEIA 12-01; Vancouver Street HDD Sewer EIA Appendix F; _N/AAPPENDIX F GEOTECHNICAL EVALUATION Geotecnnical <ind Enwronmenfai Sciences Consuitants GEOTECHNICAL EVALUATION VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA PREPARED FOR: Dudek & Associates 605 3"* Street Encinitas, Califomia 92024 PREPARED BY: Ninyo & Moore Geotechnical and Environmental Sciences Consultants 5710 Ruffin Road San Diego, Califomia 92123 August 27, 2010 ProjectNo. 106858001 ^710 Ruffin (toad • San Diego, Caiiioinia 92123 • Phone (8581 5/6-1000 • Fax (858) 576-9600 i Jieqc- • irvine • LO'Anqe!e% • ftai-'Cno Ci.ramong.j • t;a<i<-,'id • "xin .franosco • Sarwrr.entii eoiecnnicdl ond Environmental Sciences Consultants August 27, 2010 ProjectNo. 106858001 Mr. Jerod Coleman Dudek & Associates 605 3'" Street Encinitas, California 92024 Subject: Geotechnical Evaluation Vancouver Lift Station Abandonment and HDD Sewer Extension Carlsbad, California Dear Mr. Coleman: In accordance with our proposal dated May 12, 2010, and your authorization, Ninyo & Moore is pleased to submit this geotechnical evaluation report for the Vancouver Lift Station Abandonment and Horizontal Directional Drilling (HDD) Sewer Extension project in Carlsbad, Califomia. This report presents our findings, conclusions, and geotechnical recommendations for the project. We appreciate the opportunity to be of service on this project. Sincerely, NINY0\& MOORE Jeffrey T. Kent, P.E., GE. Senior Project Engineer TMG/JTK/JG/kh Distribution: (1) Addressee ihsl No. 2817 athan Goodmacher, C.E.G. 2136 / Mknager/Principal Geologist 57i0 Ruffin Road • San Diego. California 92123 • Phone (858) 5/6-1000 • Pax (858) 576-9600 San f Jiego • lr>/ine • Lo- Angeles • Rancno Cucainonga • Oakland Us Vegas • Fhoenw • Tuaori • Rescon Valley • Denver San Ftanci.'sco • SacrBmemo Ei Raso • Houston Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carlsbad, Califomia Project No. 106858001 TABLE OF CONTENTS Page 1. INTRODUCTION 1 2. SCOPE OF SERVICES 1 3. SITE AND PROJECT DESCRIPTION 2 4. SUBSURFACE EXPLORATION AND LABORATORY TESTING 2 5. GEOLOGY AND SUBSURFACE CONDITIONS 3 5.1. Regional Geology 3 5.2. Site Geology 3 5.2.1. Fill 4 5.2.2. Santiago Formation 4 5.3. Groundwater Conditions 4 5.4. Landsliding 5 6. FAULTING AND SEISMICITY 5 6.1. Strong Ground Motion 5 6.2. Ground Surface Rupture 6 6.3. Liquefaction and Seismically Induced Settlement 6 7. CONCLUSIONS 6 8. RECOMMENDATIONS 7 8.1. Earthwork 7 8.1.1. Pre-Constmction Conference 7 8.1.2. Site Preparation 7 8.1.3. Excavation Characteristics 8 8.1.4. Temporary Excavations and Shoring 8 8.1.5. Excavation Bottom Stability 9 8.1.6. Constraction Dewatering 10 8.1.7. Pipe Bedding and Modulus of Soil Reaction (E') 10 8.1.8. Trench Zone Backfill Materials 11 8.1.9. Fill Placement and Compaction 11 8.2. Lateral Pressures for Thmst Blocks 11 8.3. Seismic Design Parameters 12 8.4. Pavement Reconstmction 12 8.5. Instmmentation and Documentation 12 8.5.1. Documentation of Existing Conditions 13 8.5.2. Lateral Movement of Shoring Support System 13 8.5.3. Ground Surface Settlement 13 8.6. Soil Corrosivity 14 8.7. Concrete 14 8.8. Constmction Observation and Testing 15 9. LIMITATIONS 15 10. REFERENCES 17 imr is Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carlsbad, Cahfomia Project No. 106858001 Table Table 1 - Seismic Design Factors 12 Figures Figure 1 - Site Location Map Figure 2 - Boring Location Map Figure 3 - Fault Location Map Figure 4 - Geologic Cross Section Figure 5 - Lateral Earth Pressures for Braced Excavation Figure 6 - Thmst Block Lateral Earth Pressure Diagram Appendices Appendix A - Boring Logs Appendix B - Geotechnical Laboratory Testing llJfiS.'iSOIJI R.doc Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carlsbad, Califomia Project No. 106858001 1. INTRODUCTION This report presents the results of our geotechnical evaluation for the proposed Vancouver Lift Station Abandonment and Horizontal Directional Drilling (HDD) Sewer Extension project in Carlsbad, Califomia (Figure 1). The purpose of this study was to evaluate the geotechnical con- ditions along the proposed sewer line alignment and to provide geotechnical design recommendations for the project. 2. SCOPE OF SERVICES The scope of services for this study included the following: • Reviewing readily available background information such as stereoscopic aerial photographs and topographic and geologic maps. • Performing a geologic recoimaissance of the site to observe the existing conditions and to mark out boring locations. • Preparing and submitting a boring permit application to the County of San Diego Depart- ment of Environmental Health (DEH). • Acquiring a Right-of-Way permit from the City of Carlsbad for the subsurface evaluations on city property. • Notifying underground Service Alert (USA) and coordinating with undergroimd utility loca- tors to clear the boring locations. • Performing a subsurface exploration consisting of the excavating, logging, and sampling of four exploratory borings with a tmck-mounted drill rig. Relatively undisturbed drive, stan- dard penetration test (SPT), and bulk samples were obtained at selected intervals from within the borings. • Performing geotechnical laboratory testing of representative soil samples to evaluate in-situ moisture content and dry density, particle-size gradation, shear strength, and soil corrosivity (pH, resistivity, and sulfate and chloride contents). • Preparing this report presenting our findings, conclusions, and recommendations regarding the geotechnical design aspects of the project. 106858001 R.doc Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carlsbad, Califomia ProjectNo. 106858001 3. SITE AND PROJECT DESCRIPTION The new pipeline ahgnment will extend fi-om the eastem terminus of Via de Canto, pass through a por- tion of the Carlsbad Village Drive Habitat Conservation Area, and proceeds through Larwin Park to Vancouver Street (Figure 2). The project area is generally surrounded by single- and multi-family resi- dences. Site elevations range fi-om approximately 175 to 215 feet above mean sea level (MSL). The proposed project will involve the abandonment of the existing Vancouver Street sewer lift station and the installation of approximately 1,460 lineal feet of new sewer pipeline. Due to site restrictions, we understand that HDD constmction methods will be used to install the majority of the new pipeline. However, conventional cut and cover methods will be used for portions ofthe alignment. Although the design of the pipeline is still in the conceptual phase, we understand that due to site topography, the new pipeline may be installed at depths up to approximately 60 feet below the ground surface. 4. SUBSURFACE EXPLORATION AND LABORATORY TESTING Our subsurface exploration was conducted on July 21 and July 22, 2010. The boring locations were based on available project plans and the locations of existing improvements (Figure 2). Our subsur- face exploration consisted of the drilling, logging, and sampling of four small-diameter exploratory borings (B-1 through B-4). The borings were drilled to depths up to approximately 61 feet using tmck-moimted and limited-access drill rigs. The purpose of our borings was to observe and sample the imderlying earth materials. Relatively undisturbed in-place and bulk samples were obtained from within the borings. The samples were transported to our in-house geotechnical laboratory for testing. Logs of the borings are included in Appendix A. Laboratory testing was performed on representative soil samples collected during our subsurface exploration. The geotechnical testing included an evaluation of in-situ moisture content and dry density, particle-size gradation, shear strength, and soil corrosivity (pH, resistivity, and sulfate and chloride contents). The in-situ moisture content and dry density test results are presented at the cor- responding sample depths on the boring logs in Appendix A. The resuhs of the other laboratory tests are presented in Appendix B. |i)6S.-i8001 Rdoc 7 Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carlsbad, Cahfomia ProjectNo. 106858001 5. GEOLOGY AND SUBSURFACE CONDITIONS Our findings regarding regional geology, site geology, groundwater conditions, and landsliding are presented in the following sections. S.L Regional Geology The project study area is situated in the westem portion of the Peninsular Ranges geomorphic province of southem Califomia. This geomoiphic province encompasses an area that extends 125 miles, from the Transverse Ranges and the Los Angeles Basin, south to the Mexican border, and beyond another 775 miles to the tip of Baja Cahfomia (Norris and Webb, 1990; Harden, 1998). The geomorphic province varies in width from 30 to 100 miles, which is characterized by northwest trending mountain ranges separated by sub-paraUel fault zones. In general, the Penin- sular Ranges are underlain by Jurassic-age metavolcaiuc and metasedimentary rocks and by Cretaceous-age igneous rocks of the southem Califomia batholith. The westenmiost portion of the province in San Diego County, in which the project area is situated, generally consists of Upper Cretaceous-, Tertiary-, and Quatemary-age sedimentary rocks. The Peninsular Ranges are traversed by several major active faults (Figure 3). The Whittier- Elsinore, San Jacinto, and the San Andreas faults are major active fault systems located northeast of the site and the Rose Canyon, Coronado Bank, San Diego Trough, and San Clemente faults are active faults located to the west-southwest. Major tectonic activity associated with these and other faults within this regional tectonic framework is dominantly right-lateral strike-slip movement. These faults, as well as other faults in the region, have the potential for generating strong ground motions at the project site. 5.2. Site Geology Geologic units encountered during our subsurface evaluation include artificial fill and mate- rials of the Tertiary-aged Santiago Formation. The following sections provide descriptions of the materials encountered during our subsurface exploration. Additional descriptions are 106858001 R.doc Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Cahfomia Project No. 106858001 presented on the boring logs in Appendix A. A geologic cross section of the materials en- countered is presented on Figure 4. 5.2.L Fill Fill materials were encountered in our borings either at the ground surface or underlying the existing pavement section and extending to depths up to approximately 8 feet. As encountered, the material generally consisted of various shades of brown, damp to moist, loose to medium dense, clayey to silty sand. Scattered gravel and cobbles were encountered in the fill materials. 5.2.2. Santiago Formation Materials of the Tertiary-aged Santiago Formation were encountered below the fill ex- tending to the depths explored. As encountered, these materials generally consisted of various shades of gray and brown, damp to wet, weakly to strongly cemented, silty sand- stone interbedded with moderately to sfrongly indurated clayey siltstone. Difficult drilling conditions and auger refiisal were encountered within tiie materials of the Santiago For- mation due to concretions or zones of sfrongly cemented materials. 5.3. Groundwater Conditions Groundwater was not encountered during our subsurface exploration. However, seepage was encountered in our boring B-4 at a depth of approximately 7 feet. Additionally, existing util- ity trench lines may act as conduits for perched water conditions. Due to the site topography, nearby areas of landscaping, and the potential presence for existing utility trench lines, zones of seepage should be anticipated. Fluctuations in the groundwater level and perched condi- tions may occur due to variations in ground surface topography, subsurface geologic conditions and stracture, rainfall, irrigation, tidal fluctuations, and other factors. I06S5S0OI R.doc A Minow • Moo'Cte Vancouver Lift Station Abandoimient and HDD Sewer Extension August 27, 2010 Carisbad, Cahfomia Project No. 106858001 5.4. Landsliding Based on our review of referenced geologic maps, literature, topographic maps, and stereo- scopic aerial photographs, no landslides or indications of deep-seated landsliding were noted underlying the project site. However, areas of landslides and slope instability have been mapped (Keimedy and Tan, 2007) to the west and northeast ofthe site. 6. FAULTING AND SEISMICITY The subject site is not located within a State of Califomia Earthquake Fault Zone (formerly known as an Alquist-Priolo Special Stadies Zone; Hart and Bryant, 1997). However, the site is located in a seismically active area, as is the majority of southem Califomia, and the potential for strong ground motion in the project area is considered significant during the design life of the proposed stmcture. Figure 3 shows the approximate site location relative to the major faults in the region. The active offshore segment of the Newport-Inglewood and Rose Canyon faults are located approximately 7 miles west-southwest of the site. In general, hazards associated with seismic activity include strong ground motion, ground sur- face mpture, liquefaction, and seismically induced settlement. These hazards are discussed in the following sections. 6.1. Strong Ground Motion The 2007 Califomia Building Code (CBC) recommends that the design of stmctures be based on the horizontal peak ground acceleration (PGA) having a 2 percent probability of exceedance in 50 years which is defined as the Maxunum Considered Earthquake (MCE). The statistical re- tum period for PGAMCE is approximately 2,475 years. The probabilistic PGAMCE for the site was calculated as 0.48 g using the United States Geological Survey (USGS) (USGS, 2010) ground motion calculator (web-based). The design PGA was estimated to be 0.32 g using the USGS ground motion calculator These estimates of ground motion do not include near-source factors that may be applicable to the design of stmctures on site. 106858001 R.doc sT Vancouver Lift Station Abandonment and HDD Sewer Extension August 27,2010 Carisbad, Califomia ProjectNo. 106858001 6.2. Ground Surface Rupture Ground surface mpture due to active faulting is not considered a design issue due to the ab- sence of any known active faults underlying the site. However, lurching or cracking of the ground surface as a result of nearby seismic events is possible. 6.3. Liquefaction and Seismically Induced Settlement Liquefaction of cohesionless soils can be caused by sfrong vibratory motion due to earth- quakes. Research and historical data indicate that loose granular soils and non-plastic silts that are saturated by a relatively shallow groundwater table are susceptible to liquefaction. Based on the relatively dense nature of the underlying earth materials and the absence of a shallow groundwater table, it is our opinion that the potential for liquefaction and seismi- cally induced settlement to occur at the site is not a design consideration. 7. CONCLUSIONS Based on our field reconnaissance, subsurface exploration and laboratory testing, it is our opin- ion that there are no known geotechnical or geologic constraints that would preclude constmction of the proposed pipeline facility provided that the geotechnical and geologic rec- ommendations discussed in this report are considered, and the appropriate evaluation, design, and constraction criteria are followed. The geotechnical design and constmction considerations are described in the following sections. • The site is generally underlain by fill and materials of the Santiago Formation. • The on-site fill materials should be generally excavatable with conventional heavy-duty earth moving constmction equipment in generally good condition. However, difficult drill- ing conditions, including auger refusal, were encountered during the drilling of our exploratory borings. Accordingly, difficult excavating or drilling conditions should be an- ticipated due to concretions or strongly cemented zones within the Santiago Formation. • Although groundwater was not encountered, seepage was encountered at a depth of approxi- mately 7 feet m Boring B-4. The contractor should be prepared to address issues assodated with seepage such excavation stability and presence of wet soils. 106858001 R.doc Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carlsbad, Califomia Project No. 106858001 • Materials derived from on-site excavations are generally considered suitable for reuse as back- fill provided they meet the recommendations for trench backfill material presented in the following sections. • Based on the results of our soil corrosivity tests presented in the foUowing sections and Calfrans corrosion guidelines (2003), the site is classified as corrosive. 8. RECOMMENDATIONS The following sections present our geotechnical recommendations for the proposed project. If the proposed constmction is changed from that discussed in this report, Ninyo & Moore should be contacted for additional recommendations. S.L 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 recommenda- tions or guidelines presented herein. 8.1.L Pre-Construction Conference We recommend that a pre-constmction conference be held. The owner and/or their rep- resentative, the goveming agencies' representatives, the civil engineer, Ninyo & Moore, and the contractor should be in attendance to discuss the work plan, project schedule, earthwork, and shoring requirements. 8.1.2. Site Preparation Prior to performing site excavations, the site should be cleared of vegetation, surface obstmctions, mbble and debris, abandoned utilities and foundations, and other deleteri- ous materials. Existing utilities within the project limits, if any, should be re-routed or protected from damage by constmction activities. Obstmctions that extend below finish grade, if any, should be removed and the resulting holes filled with compacted soils. Materials generated from the clearing operations should be removed from the project site and disposed of at a legal dumpsite. 106858001 R.doc -7 Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Cahfomia Project No. 106858001 8.L3. Excavation Characteristics Our evaluation of the excavation characteristics of the on-site materials is based on the results of our exploratory borings, our site observations, and our experience with similar materials. Difficult drilling conditions and auger refusal were encountered during the performance of our borings. Due to the potential presence of concretions and sfrongly cemented zones within the Santiago Formation, difficulty for the performance of exca- vations and drilling operations should be anticipated. 8.1.4. Temporary Excavations and Shoring For temporary excavations, we recommend that the foUowing Occupational Safety and Health Administration (OSHA) soil classifications be used: Fill Type C Santiago Formation Type B Upon making the excavations, the soil classifications and excavation performance should be evaluated in the field by the geotechnical consultant in accordance with the OSHA regu- lations. Temporary excavations should be consfructed in accordance with OSHA recommendations. For trench or other excavations, OSHA requfrements regarding person- nel safety should be met using appropriate shoring (including french boxes) or by laying back the slopes to no steeper than 1.5:1 (horizontal: vertical) in fill and 1:1 in materials of the Santiago Formation. Temporary excavations that encounter seepage may be shored or stabilized by placing sandbags or gravel along the base of tiie seepage zone. Excavations encountering seepage should be evaluated on a case-by-case basis. On-site safety of per- sonnel is the responsibility ofthe contractor In areas with limited space for constmction where temporary excavations may not be laid back at the recommended slope inclination, a shoring system with bracing may be incor- porated to stabilize the excavation sidewaUs during constmction. The shoring system should be designed using the magnitude and distribution of lateral earth pressures pre- sented on Figure 5. The recommended design earth pressures are based on the in Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Califomia Project No. 106858001 assumptions that (a) the shoring system is constracted without raising the ground surface elevation behind the shoring, (b) fhat there are no surcharge loads, such as soil stockpiles, constmction materials, constmction equipment, or vehicular traffic, and (c) that no loads act above a 1:1 plane extending up and back from the base of the shoring system. For shoring subjected to the above-mentioned surcharge loads, the confractor should include the effect of these loads on lateral earth pressures acting on the shoring wall. Settlement of the ground surface may occur behind the shoring wall during excavation. The amount of settlement depends on the type of shoring system, the quality of confrac- tor's workmanship, and soil conditions. Settlement may cause distress to adjacent stmctures, if present. To reduce the potential for disfress to adjacent stmctures, we rec- ommend that the shoring system be designed to limit the ground settlement behind the shoring to Yi inch or less. Possible causes of settlement that should be addressed include vibration during installation of the sheet piling, excavation for constmction, constmction vibrations, dewatering, and removal of the support system. We recommend that the poten- tial settlement distress be evaluated carefully by the confractor prior to constmction. The contractor should retain a quahfied and experienced engineer to design the shoring sys- tem. The shoring parameters presented in this report are preliminary design criteria, and the confractor should evaluate the adequacy of these parameters and make appropriate modifi- cations for thefr design. We recommend that the confractor take appropriate measures to protect workers. OSHA requfrements pertaining to worker safety should be observed. We further recommend that the constmction methods provided herein be carefuUy evaluated by a qualified specialty contractor prior to commencement of the constmction. 8.1.5. Excavation Bottom Stability In general, we anticipate that the bottom of the pipeline frenches wdl remain stable and provide suitable support to the proposed utility lines. However, excavations that extend near or below the water table and/or seepage conditions (if encountered) may be unstable. In general, unstable bottom conditions may warrant overexcavation and replacement with 106S5S00I R.doc Vancouver Lift Station Abandonment and HDD Sewer Extension August 27,2010 Carisbad, Cahfomia Project No. 106858001 gravel. However, recommendations for stabilizing excavation bottoms should be based on evaluation in the field by the geotechnical consultant at the time of constmction. 8.1.6. Construction Dewatering Seepage conditions were encountered in Boring B-4 at a depth of 7 feet. Dewatering measures during excavation operations should be prepared by the contractor's engineer and reviewed by the design engineer Considerations for constmction dewatering should include anticipated drawdown, piping of soils, volume of pumping, potential for settle- ment, and groundwater discharge. Disposal of groundwater should be performed in accordance with guidelines of the Regional Water Quality Control Board (RWQCB). 8.1.7. Pipe Bedding and Modulus of Soil Reaction (E') We recommend that the new pipelines (pipes), where constmcted in open excavations, be supported on 6 or more inches of granular bedding material. 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 pipe bedding should conform to the specifications presented for pipe zone backfill materials. Pipe bedding and pipe zone backfill should have a Sand Equivalent (SE) of 30 or greater, and be placed around the sides and top of the pipe. In addition, the pipe zone backfiU should extend 1 foot or more above the top of the pipe. The modulus of soil reaction {£') is used to characterize the stiffiiess of soil backfill placed at the sides of buried flexible pipes for the purpose of evaluating deflection caused by the weight ofthe backfUl 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 about 5 feet when backfilled with granular soil compacted to a relative compaction of 90 percent as evaluated by the American Society for Testing and Materials (ASTM) D 1557. A sod re- action modulus of 1,800 psi may be used for trenches deeper than 5 feet. 106858001 R.doc ,fl»^ Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carlsbad, Califomia ProjectNo. 106858001 8.1.8. Trench Zone Backfill Materials In general, on-site soils with an organic content of less than approximately 3 percent by vol- ume (or 1 percent by weight) are suitable for use as trench zone backfill. For the purpose of this report, the trench zone is considered to extend from 1 foot above the top of the pipe to the top of the trench. The backfill material should not generally contain rocks or lumps greater than approximately 3 inches, and particles not more than approximately 30 percent larger than % inch. Larger chunks, if generated during excavation, may be broken into ac- ceptably sized pieces or disposed of offsite. Imported fill material, if needed for the project, should generally be granular soils with a very low to low expansion potential. Import mate- rials should also be non-corrosive in accordance with the Calfrans (2003) corrosion guidelines. Materials for use as backfill should be evaluated by Ninyo & Moore's represen- tative prior to fiUing or importing. 8.1.9. Fill Placement and Compaction Fill and trench backfill should be compacted by mechanical methods in uniform horizontal lifts to a relative compaction of 90 percent as evaluated by the latest edition of ASTM D 1557. The upper 12 inches of sfreet subgrade and aggregate base beneath pave- ment areas should be compacted to a relative compaction of 95 percent. FiU and trench backfill sods should be placed at or above the laboratory optimum moisture content as evaluated by the latest edition of ASTM D 1557. The optimum lift tiiickness of fiU wdl de- pend on the type of compaction equipment used, but generally should not exceed 8 inches in loose thickness. Successive lifts should be freated in a like manner until the desfred fin- ished grades are achieved. Special care should be taken to avoid pipe damage when compacting trench backfill above the pipe. 8.2. Lateral Pressures for Thrust Blocks Thmst restraint for buried pipelines may be achieved by transferring the thrust force to the soil outside the pipe through a thmst block. Thmst blocks may be designed using the magni- tude and distribution of passive lateral earth pressures presented on Figure 6. Thmst blocks 105858001 R.doc 1 | Vancouver Lift Station Abandonment and HDD Sewer Extension Carlsbad, Califomia August 27, 2010 ProjectNo. 106858001 should be backfilled with granular backfill material and compacted following the recom- mendations presented in this report. 8.3. Seismic Design Parameters The proposed improvements should be designed in accordance with the requirements of goveming jurisdictions and applicable building codes. Table 1 presents the seismic design parameters for the site, according to the 2007 CBC and mapped spectral acceleration pa- rameters (USGS, 2010). Table 1 - Seismic Design Factors Factors Values Site Class C Site Coefficient, Eg 1.000 Site Coefficient, Fv 1.348 Mapped Short Period Spectral Acceleration, Ss 1.191g Mapped One-Second Period Spectral Acceleration, 0.452g Short Period Spectral Acceleration Adjusted For Site Class, SMS 1.191g One-Second Period Spectral Acceleration Adjusted For Site Class, SMI 0.609g Design Short Period Spectral Acceleration, SDS 0.794g Design One-Second Period Spectral Acceleration, SDI 0.406g 8.4. Pavement Reconstruction Trenching within the street rights-of-way will result in the replacement of pavements for the project. In general, pavement repair should conform to the material and compaction re- quirements of the adjacent pavement section. Aggregate base material and asphalt concrete should be compacted to 95 percent. Actual pavement reconstmction should conform to the requirements of the appropriate goveming agency. 8.5. Instrumentation and Documentation Consideration should be given to implementing documentation and instmmentation programs to evaluate design assumptions, existing conditions, and to monitor movements, levels and defor- mations during constmction. The monitoring programs may include the use of seismographs, groundwater monitoring wells, inclinometers, convergence points and an array of surface confrol 106S5S001 R.doc 12 /^3f^- Mauri c Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Cahfomia Project No. 106858001 points. The resulting data should be reviewed and evaluated by the geotechnical consultant. These programs should be in-place or conducted prior to the start of constraction. 8.5.1. Documentation of Existing Conditions We recommend a pre-constmction survey be performed on residences and stractures within approximately 50 feet of proposed trench excavations. The surveys should in- clude photo-documenting existing cracks, and measuring crack widths and vertical separations, if applicable. Consideration may be given to videotaping the survey. In ad- dition, interviews with property owners should be conducted to provide knowledge of the age and type of the buildings as well as maintenance history and utility problems. 8.5.2. Lateral Movement of Shoring Support System We recommend that inclinometers or survey points be established behind excavations located in areas where stractures are located above a 1:1 plane projected from the bot- tom of proposed excavations. We recommend that an evaluation of the final project plans be performed to see if other stractures or sensitive site improvements are located within close proximity of proposed excavations. The inclinometers or survey points should be monitored and evaluated daily during excavation activities to provide an ad- vanced waming system of potential problems. 8.5.3. Ground Surface Settlement We also recommend an array of ground survey points be installed along the utility line alignment to monitor settlement. The survey points should be installed as close as prac- tical to the excavation and incrementally away from the excavation. We recommend that the contractor be responsible for maintaining the total settlement beneath adjacent buildings to less than Vi inch. If settlements reach 14 inch, we recommend that a review ofthe contractor's methods be performed and appropriate changes be made, if needed. Consideration can be given to placing survey monitoring points on nearby stracmres to monitor the performance of the stmctures. In this way, a record of the performance of 106858001 R.doc Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Cahfomia Project No. 106858001 the stracture will be maintained and available. This information, in conjunction with pre-constraction surveys, is helpful in reducing potential claims and expediting and lim- iting settlement of legitimate claims. 8.6. Soil Corrosivity The corrosion potential of the site soils was evaluated based on laboratory testing of a repre- sentative sample obtained from our exploratory borings. Laboratory testing was performed to evaluate pH, electrical resistivity, chloride and sulfate content. The laboratory test results are presented in Appendix B. The pH of the tested samples was approximately 7.9, the electrical resistivity ranged from approximately 550 to 600 ohm-centimeters (ohm-cm), the chloride content ranged from ap- proximately 360 to 460 parts per million (ppm), and the sulfate content ranged from approximately 0.058 to 0.061 percent (i.e., 580 to 610 ppm). Based on the laboratory test re- sults and Caltrans (2003) corrosion criteria, the project site is classified as a corrosive site. According to Caltrans (2003) corrosion criteria, site is considered corrosive if the earth ma- terials have more than 500 ppm chlorides, more than 0.20 percent sulfates (i.e., 2,000 ppm), a pH of 5.5 or less or an electrical resistivity of less than 1,000 ohm-cm. 8.7. Concrete Concrete in contact with soil or water that contains high concentrations of water-soluble sul- fates can be subject to premamre chemical and/or physical deterioration. As stated above, the soil samples tested in this evaluation indicated a water-soluble sulfate content that ranged from approximately 0.058 to 0.061 percent by weight (i.e., 580 to 610 ppm). Accord- ing to the American Concrete Institute (ACI) 318-05, the potential for sulfate attack is moderate for water-soluble sulfate contents between 0.10 and 0.20 percent by weight (i.e., 100 to 200 ppm) in soils. Therefore, the site soils are considered negligible for sulfate attack. Although significant sulfate content was not indicated, we recommend that Type V cement 106S5S001 R.doc 1 A Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Cahfomia Project No. 106858001 should be used for concrete constraction with a water-cement ratio no higher than 0.45 by weight for normal weight aggregate concrete. 8.8. Construction Observation and Testing During constraction operations, we recommend that Ninyo & Moore perform observation and testing services. These services should be performed to evaluate exposed subgrade con- ditions, including the extent and depth of overexcavation, the suitability of proposed borrow materials for use as fill, and placement and testing of fill soils compaction. If a geotechnical consultant other than Ninyo & Moore is selected to perform observation and testing services for the project, we request that the selected consultant provide a letter to the owner, with a copy to Ninyo & Moore, indicating that they fully understand our recommendations, and that they are in agreement with the recommendations contained in this report. Constraction of proposed improvements should be performed by qualified subcontractors using appropri- ate techniques and constraction materials. 9. 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 pre- sented 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 constmction. Uncertainties relative to subsurface conditions can be reduced through addi- tional subsurface exploration. Additional subsurface evaluation will be performed upon request. Please also note that our evaluation was limited to assessment of the geotechnical aspects of the project, and did not include evaluation of stmcmral issues, environmental concems, or the pres- ence of hazardous materials. 106S5S001 Rdoc 1 c Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Cahfomia Project No. 106858001 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 thefr geotechnical consultant per- form 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 govemment ac- tion 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, conclu- sions, and/or recommendations of this report by parties other than the client is undertaken at said parties' sole risk. Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Califomia Project No. 106858001 10. REFERENCES American Concrete Institute (ACI), 2005, ACI 318-05 Building Code Requirements for Strac- tural Concrete and Commentary. Anderson, J.G., Rockwell, T.K., and Agnew, D.C, 1989, Past and Possible Future Earthquakes of Significance to the San Diego Region: Earthquake Engineering Research Institute (EERI), Earthquake Spectra, Volume 5, No. 2. Blake, TF, 2001, FRISKSP (Version 4.00) A Computer Program for tiie Probabihstic Estunation of Peak Acceleration and Uniform Hazard Specfra Using 3-D Fauhs as Earthquake Sources. Califomia Building Standards Commission, 2007, Califomia Building Code, Title 24, Part 2, Volumes 1 and 2: dated June. Cahfomia Department of Transportation (Caltrans), 2003, Corrosion Guidelmes (Version 1.0), Divi- sion of Engineering and Testing Services, Corrosion Technology Branch: dated September. Cahfomia Geological Survey, 1998, Maps of Known Active Fault Near-Source Zones in Califor- nia and Adjacent Portions of Nevada: dated Febmary. Califomia Geological Survey, 1999, Seismic Shaking Hazard Maps of Cahfomia: Map Sheet 48. Cao, T., Biyant, W. A., Rowshandel, B., Branum, D., and Willis, C. J., 2003, The Revised 2002 Cahfomia Probabilistic Seismic Hazards Maps: Califomia Geological Survey: dated June. County of San Diego, 2010, SanGIS, World Wide Web, http://www.sangis.org/SangisInteractive. Geotracker website, 2010, www, geotracker com. Harden, D.R., 1998, Cahfomia Geology: Prentice Hall, Inc. Hart, E.W., and Bryant, W.A., 1997, Fault-Ruptore Hazard Zones in Califomia, Alquist-Priolo Earthquake Fault Zoning Act with Index to Earthquake Fault Zone Maps: Califomia De- partment of Conservation, Division of Mines and Geology, Special Publication 42. Hartley, J.D., and Duncan, J.M., 1987, E' and Its Variation with Depth: American Society of Civil Engineers (ASCE), Joumal of Transportation Engineering, Vol. 113, No. 5: dated September Jennings, C.W, and Bryant, W.A., 2010, Fauh Activity Map of Cahfomia: Califomia Geological Sur- vey, Califomia Geologic Data Map Series: Map No. 6, Scale 1:750,000. Kennedy, M.P., and Tan, S.S., 1996, Geologic Maps of the Northwestem Part of San Diego County, Cahfomia, Open-File Report 96-02. Kennedy, M.P. and Tan, S.S., 2007, Geologic Map of tiie Oceanside 30' x 60' (Quadrangle, Cahfomia, Cahfomia Geological Survey, Regional Map Series, 1:100,000 Scale, Map No. 2. Ninyo & Moore, In-house proprietary information. 106858001 R.doc l 7 Vancouver Lift Station Abandonment and HDD Sewer Extension August 27,2010 Carisbad, Cahfomia Project No. 106858001 Ninyo & Moore, 2010, Proposal for Geotechnical Evaluation, Proposed Sewer Line from Van- couver Street to Via de Canto, Carlsbad, Cahfomia, Proposal No. P-8844: dated May 12. Norris, R.M., and Webb, R.W., 1990, Geology of Califomia, Second Edition: John WUey & Sons, Inc. Public Works Standards, Inc., 2009, "Greenbook," Standard Specifications for Public Works Constmction. Tan, S.S., and Giffen, D.G, 1995, Landslide Hazards in the Northem Part of the San Diego Met- ropolitan Area, San Diego County, Califomia, Califomia Division of Mines and Geology, Landslide Hazard Identification map No. 35, Open File Report 95-04, Scale 1:24.000. Treiman, J.A., 1984, The Rose Canyon Fault Zone, A Review and Analysis: Califomia Geologi- cal Survey. Treiman, J.A., 1993, The Rose Canyon Fault Zone, Southem Califomia: Califomia Geological Survey, Open FUe Report 93-02. United States Department of the Interior, Bureau of Reclamation, 1989, Engineering Geology Field Manual. United States Geological Survey (USGS), 1968 (Photorevised 1975), San Luis Rey Quadrangle- Califomia, San Diego County, 7.5 Minute Series (Topographic): Scale 1" = 2,000'. United States Geological Survey/Califomia Geological Survey, 2002 (Revised April 2003), Probabilistic Seismic Hazards Assessment (PSHA) Model, World Wide Web, http://www.consrv.ca.gov/CGS/rghm/pshamap/pshamain.html. United States Geological Survey, 2010, Ground Motion Parameter Calculator v. 5.0.9, World Wide Web, http://earthquake.usgs.gov/research/hazmaps/design/. AERIAL PHOTOGRAPHS Source Date Flight Numbers Scale USDA April 11, 1953 AXN-8M 103 and 104 1:24,000 1O6S5S00I R.doc I o HmmsrA SOURCE: 2008 Thomas Guide for San Diego County, Streel Guide and Directory: Map ©Rand McNally R.L,07-S-129 APPROXIMATE SCALE N NOTE: ALL DIRECTIOIMS. DIMENSIONS AND LOCATIONS ARE APPROXltulATE 2,400 4,800 FEET SITE LOCATION MAP FIGURE 1 PROJECT NO DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE 1 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE 1 ^ B-4 TD=15.5' BORING, TD = TOTAL DEPTH IN FEET PROPOSED SEWER ALIGNMENT/ A A' I I I GEOLOGIC CROSS SECTION (14) (STATION NUMBER) SOURCE Alignment - Dudek, 2010: Aerial Imagery - Pliolo Date: January 2009. ESRI. i-cubed, USDAFSA, USGS, AEX, GeoEye, Gelmapping Aerogrid, IGR N NOTE: ALL DIRECTIONS, DllvlENSIONS AND LOCATIONS ARE APPROXIMATE A APPROXIMATE SCALE 140 280 FEET BORING LOCATION MAP FIGURE 2 PROJECT NO. DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE 2 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE 2 N A ^\=c:- :-*\ '"^''"-^s^---..*-! SAN ^'k^ ^"^'y - •^ousandi^. - ^,,.a.Vo^i^^^*ynine Palms >-<:, , : Palmdale ^©aks V.' ir_''*At)isux;p^i; •A\°^ •Riverside^" Lp.s-Angeles f'Beach,»'->i • Santa?6V'~*^ temecula BAHN S%fi Bernardino <^(ii4ntK Palm-. Springs H: An'a-, jifvinej \ ^Clemente levari Wr~^ Riverside Coujity^; - - Desert %%^©feanside / San tlif^QO Courtti^ ~| Impertar CoL/nty Escondido ' / O. • p .San ... P A -G./ F / C O CEA N :0 • "J^,' ' T f- Chula Visia USA: MEXICO LEGEND CALIFORNIA FAULT ACTIVITY HISTORICALLY ACTIVE HOLOCENE ACTIVE LATE QUATERNARY (POTENTIALLY ACTIVE) QUATERNARY (POTENTIALLY ACTIVE) STATE/COUNTY BOUNDARY SOURCE: Fault Activity Map of Califomia. 2010, Jennings. C.W.. and Bryant, W.A., California Geological Survey APPROXIMATE SCALE 30 60 MILES NOTES: ALL DlRECTiONS. DIMENSIONS AND LOCATIONS ARE APPROXIMATE FAULT LOCATION MAP FIGURE 3 PROJECT NO. DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE 3 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE 3 250- 200 • o h-< > UJ 100 • 250 Qaf/Topsoil B-3 (PROJECTED 110') EXISTING GROUND SURFACE \ Qaf/Topsoil _L 82/11" (SPT) 50/4- (SPT) TD=60.8' Tsa 4+00 5+00 6+00 7+00 -250 -200 i 5 •150 > UJ _j UJ -100 150- -3 EXISTING GROUND SURFACE B-2 (PROJECTED 50') Tsa • • 79 (SPT) 50/5- (SPT) 50/4" (SPT) 50/4-50/6" 60/6-50/3" Qaf/Topsoil L_ EDGE OF PARKING LOT I EDGE OF VANCOUVER B-1 STREET (PROJECTED 5') A' .Jl • 49 • 50/1" TD=25.6' TD=50.8' Tsa r250 •200 (MS z o 1- -150 < > Ul _i LU -100 7+00 8+00 9+00 10+00 11+00 12+00 13+00 14+00 14+56 LEGEND B-4 1 APPROXIMATE LOCATION OF EXPLORATORY BORING 4- 50/5-SAMPLE BLOW COUNT PER INCREMENT OF DEPTH TD = 15.5' TD=TOTAL DEPTH IN FEET Qaf FILL Tsa SANTIAGO FORMATION 7 GEOLOGIC CONTACT, QUERIED WHERE QUESTIONABLE NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE APPROXIMATE SCALE 0 100 200 FEET SOURCE: DUDEK, 2010, ALIGNMENT FOH VANCOUVER UFT STATION; DATED JULY 27. GEOLOGIC CROSS SECTION FIGURE 4 PROJECT NO. DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, GALIFORNIA FIGURE 4 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, GALIFORNIA FIGURE 4 1) Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carisbad, Califomia Project No. 106858001 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 borings. The samples were bagged and transported to the laboratory for testing. The Standard Penetration Test tSPT) Sampler Disturbed drive samples of earth materials were obtained by means of a Standard Penetra- tion Test sampler The sampler is composed of a split barrel with an extemal diameter of 2 inches and an unlined intemal diameter of 1-3/8 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 pene- tration. 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 methods. 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 sam- pled. The samples were removed from the sample barrel in the brass rings, sealed, and transported to the laboratory for testing. 1068.^8001 R.doc 8 u. i UJ a: O cr o W z UJ Q Q Z o ii o BORING LOG EXPLANATION SHEET I 1 10- xx/xx 9 SL Bulk sample. Modified split-barrel drive sampler. No recovery with modified split-barrel drive sampler. Sample retained by others. Standard Penetration Test (SPT). No recovery with a SPT. Shelby tube sample. Distance pushed in inches/length of sample recovered in inches. No recovery with Shelby tube sampler. Continuous Push Sample. Seepage. Groundwater encountered during drilling. Groundwater measured after drilling. 15 SM ALLUVIUM: Solid line denotes unit change. Dashed line denotes niaterial change. Attitudes: Strike/Dip b: Bedding c: Contact j: Joint f: Fracture F; Fault cs: Clay Seam s: Shear bss: Basal Slide Surface sf: Shear Fracture sz: Shear Zone sbs: Sheared Bedding Surface The total depth line is a solid line that is drawn at the bottom of the boring. BORING LOG EXPLANATION OF BORING LOG SYMBOLS PROJECT NO. DATE Rev. 01/03 FIGURE U.S.C.S. METHOD OF SOIL CLASSIFICATION MAJOR DIVISIONS SYMBOL TYPICAL NAMES 1/3 -4 O t/3 P M i o I ta (/) < O o o o o (N d Z A GRAVELS (More than 1/2 of coarse fraction > No. 4 sieve size) • GM SANDS (More than 1/2 of coarse fraction <No. 4 sieve size) GW GP GC SW SP SM SC Well graded gravels or gravel-sand mixtures, little or no fines Poorly graded gravels or gravel-sand mixtures, little or no fines Silty gravels, gravel-sand-silt mixtures Clayey gravels, gravel-sand-clay mixtures Well graded sands or gravelly sands, little or no fines Poorly graded sands or gravelly sands, little or no fines Silty sands, sand-silt mixtures Clayey sands, sand-clay mixtures -J O c/3 Q < OS a I •S o z ^ V SILTS & CLAYS Liquid Limit <50 ML Inorganic silts and very fine sands, rock flour, silty or clayey fine sands or clayey silts with CL Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean OL SILTS & CLAVS Liquid Limit >50 Organic silts and organic silty clays of low plasticity MH Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts CH Inorganic clays of high plasticity, fat clays OH Organic clays of medium to high plasticity, organic silty clays, organic silts HIGHLY ORGANIC SOILS Pt Peat and other highly organic soils GRAIN SIZE CHART CLASSIFICATION RANGE OF GRAIN SIZE CLASSIFICATION U.S. Standard Sieve Size Grain Size in Millimeters BOULDERS Above 12" Above 305 COBBLES 12"to 3" 305 to 76.2 GRAVEL Coarse Fine 3" to No. 4 3" to 3/4" 3/4" to No. 4 76.2 to 4.76 76.2 to 19.1 19.1 to 4.76 SAND Coarse Medium Fine No. 4 to No. 200 No. 4 to No. 10 No. 10 to No. 40 No. 40 to No. 200 4.76 to 0.075 4.76 to 2.00 2.00 to 0.420 0.420 to 0.075 SILT & CLAY Below No. 200 Below 0.075 PLASTICITY CHART ^ 50 • s ^ 40 . i z CH ^ 50 • s ^ 40 . i z nciTY CL !,OH CL- IV L / M L&OL 1 ) 10 2 0 3 0 4 0 50 6 0 70 8 0 90 100 LIQl lD LIMIT(LL), % U.S.C.S. METHOD OF SOIL CLASSIFICATION uses Soil Ciassit'icatioii Updated No\ 2(104 o o u. 1 CQ U- o Q. RE TY w 1-z « UJ o Q 5 DRY < CO yd fcc/3 CO _: r o DATE DRILLED 7/21/10 BORING NO. B-1 GROUND ELEVATION 206' ± (MSL) SHEET 1 OF IVIETHOD OF DRILLING 6" Diameter Hollow Stem Auger (CME-75) (Baja Exploration) DRIVE WEIGHT 140 lbs. (Auto-Trip Hammer) DROP 30" SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION 31 ASPHALT CONCRETE: 10.7 119.4 SM v^pproximately 6 inches thick. SC BASE MATERIAL: pray, damp to moist, loose to medium dnese, silty fine SAND; some fine to coarse gravel; race clay; approximately 3 inches thick. FILL: Light yellowish brown, damp to moist, medium dense, clayey SAND. 10 I 50/6" 15~- 50/6" JUl. 13.9 115.4 14 1 113.8 SANTIAGO FORMATION: Very light grayish brown, damp to moist, weakly to moderately cemented, silty fine- grained SANDSTONE interbedded with moderately indurated clayey SILTSTONE. Grayish brown. BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CAUFORNIA PROJECT NO. 106858001 DATE 8/10 FIGURE A-1 CO UJ _1 a. < CO Q. UJ Q o O u. i UJ DC z> h-» o o CL UJ a >• a: Q O m S > CO z g 5 CO yd CO (O _: CO ^ O DATE DRILLED 7/21/10 BORING NO. GROUND ELEVATION 206'± (MSL) SHEET OF IVIETHOD OF DRILLING 6" Diameter Hollow Stem Auger (CME-75) (Baja Exploration) DRIVE WEIGHT 140 lbs. (Auto-Trip Hammer) DROP 30" SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION 49 13.0 115.4 SANTIAGO FORMATION: (Confinued) Grayish brown, damp to moist, weakly to moderately cemented, silty fine-grained SANDSTONE interbedded moderately indurated with clayey SILTSTONE; trace coarse sand to fine gravel. 25- 50/1" Total Depth = 25.6 feet. Groundwater not encountered during drilling. Backfilled with approximately 5 cubic feet of bentonite grout and patched with asphalt concrete shortly after drilling on 7/21/10. Note: Groundwater, though not encountered at the time of drilling, may rise to a higher level due to seasonal variations in precipitation and several other factors as discussed in the report. 30- 35 - 40 BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA PROJECTNO. 106858001 DATE 8/10 FIGURE A-2 CO UJ < CO CL UJ o o o u. i o UJ a: H CO O o CL CO z UJ Q >-a: a z O I- . < CO CO o DATE DRILLED 7/22/10 BORING NO. B-2 GROUND ELEVATION 207' ± (MSL) SHEET 1 OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (Limited Access Rig, CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip Hammer) DROP 30;; SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION 10 15- _2Q_ SM FILL; Light grayish brown, damp to moist, loose, silty fine SAND; few fine to coarse gravel; contains roots in upper 6 inches. Light yellowish brown; medium dense. Dark brown; loose; silty fine to medium sand. 79 SANTIAGO FORMATION: Light grayish brown, damp, weakly cemented, silty fine-grained SANDSTONE. "GrayTsliT)rown, damp, weakly to moderately cemented, siltyTine-grained SANDSTONE interbedded with moderately indurated clayey SILTSTONE. ill I BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA PROJECT NO. I068580Q1 DATE 8/10 FIGURE A-3 X I-CL UJ Q I-O o LL CO O UJ a: CO o o CL UJ Q >-a: a z O CO o DATE DRILLED 7/22/10 BORING NO. B-2 GROUND ELEVATION 207' ± (MSL) SHEET OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (Limited Access Rig, CME-7S) (Baja) DRIVE WEIGHT 140 lbs, (Auto-Trip Hammer) DROP 30;; SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION "TIT 50/5" 25 30 50/4" I 50/4" -AH SANTIAGO FORMATION: (Continued) Grayish brown, damp, weakly to moderately cemented, silty fine-grained SANDSTONE interbedded with moderately indurated clayey SILTSTONE. 108.2 Light gray, damp, wea0y to strongly cemented, sUty fine-grained SANDSTONE. BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA PROJECTNO. 106858001 DATE 8/10 FIGURE A-4 X I- CL UJ Q O O UJ cc D F-W o 5 U-o D- CO z ill > DC a z O I- , < CO yd r o DATE DRILLED 7/22/10 BORING NO, B-2 GROUND ELEVATION 207' ± (MSL) SHEET OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (Limited Access Rig, CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip Hammer) DROP 30;; SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION ~W 50/6" 9.0 104.7 45 50/6" 8.7 104.1 50- 50/3" 19.2 96.8 SANTIAGO FORMATION: (Continued) Light gray, damp, weakly to strongly cemented, silty fine-grained SANDSTONE. Gray and grayish brown, damp, weakly to strongly cementedTsHty fme-grained" SANDSTONE interbedded with strongly indurated clayey SILTSTONE. Moist. Total Depth"= SO.STeet. Groundwater not encountered during drilling. Backfilled with approximately 17.7 cubic feet of bentonite grout shortly after drilling on 7/22/10. Note: Groundwater, though not encountered at the time of drilling, may rise to a higher level due to seasonal variations in precipitafion and several other factors as discussed in the report. 55- 60 BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA PROJECTNO, 106858001 DATE 8/10 FIGURE A-5 CO Ul _1 CL 5 < CO X I-CL O o o _l CQ 10 46 15- cc w O o Q. CO z UJ D >-OC o z g ^« CO ^ o SM DATE DRILLED 7/21/10-7/22/10 BORING NO. B-3 GROUND ELEVATION 210'± (MSL) SHEET 1 OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (Limited Access Rig, CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip Hammer) DROP 30" SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION FILL: Light grayish brown, damp, loose, silty fine SAND; trace medium to coarse sand; trace \clay; scattered fine to coarse gravel and cobbles. SANTIAGO FORMATION: Light grayish brovm, damp, weakly cemented, silty fine-grained SANDSTONE interbedded with moderately indurated clayey SILTSTONE. BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA PROJECT NO. 106858001 DATE 8/10 FIGURE A-6 CO UJ _J CL < CO o O CL UJ Q UJ a: I- co o u. o CL UJ Q >-cc a jM4 z g I- , < CO yd CO -3 o DATE DRILLED 7/21/10-7/22/10 BORING NO, B-3 GROUND ELEVATION 210'±(MSL) SHEET OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (Limited Access Rig, CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip Hammer) DROP 30;; SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION 50/6" 25 r 50/5" 30- 35- SANTIAGO FORMATION: (Continued) Light grayish brown, damp, weakly to strongly cemented, silty fine-grained SANDSTONE interbedded with strongly indurated clayey SILTSTONE. Refusal at 35 feet. Moved over 10 feet and re-drilled with 8" Hollow Stem Auger Limited Access Rig (CME-75) on 7/22/10. BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA PROJECTNO. 106858001 DATE 8/10 FIGURE A-7 CO UJ _J a < CO X H CL UJ a o o u. UJ cc CO o u. CJ CL CO z UJ a > cc Q o CQ > CO z g H . < CO Od t CO CO CO -> DATE DRILLED 7/21/10-7./22/10 BORING NO. B-3 GROUND ELEVATION 210'±(MSL) SHEET OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (Umited Access Rig, CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip Hammer) DROP 30;; SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION TIT 45- 50 f 82/11" 55- SANTIAGO FORMATION: (Continued) Grayish brown, damp, weakly to strongly cemented, silty fine-grained SANDSTONE interbedded with strongly indurated clayey SILTSTONE. BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA PROJECT NO. 106858001 DATE 8/10 FIGURE A-8 CO UJ Q. S X t-Q. UJ Q h-O o UJ U_ CC CO o iSli —J O CD o a w z UJ D >- Q g t- . < CO yd o DATE DRILLED 7/21/10-7/22.'! 0 BORING NO B-3 GROUND ELEVATION 210'±(MSL) SHEET OF METHOD OF DRILLING 8" Diameter Hollow Stem Auger (Limited Access Rig, CME-75) (Baja) DRIVE WEIGHT 140 lbs. (Auto-Trip Hammer) DROP 30" SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION "ST 50/4" 65 - 70- 75- S ANTI AGO FORMATION: (Continued) Grayish brown, damp, weakly to strongly cemented, silty fine-grained SANDSTONE ^interbedded with strongly indurated clayey SILTSTONE. First Attempt Totai Depth = 35 feet. Groundwater not encountered during drilling Backfilled with approximately 6.9 cubic feet of bentonite grout shortly after drilling on 7/ 21/10. Second Attempt Total Depth = 60.8 feet. Groundwater not encountered during drilling. Backfilled with approximately 21.2 cubic feet of bentonite grout shortly after drilling on 7/22/10. Note: Groundwater, though not encountered at the time of drilling, may rise to a higher level due to seasonal variations in precipitation and several other factors as discussed in the report. BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION C.iiRLSBAD, CALIFORNIA PROJECT NO. 106858001 DATE 8/10 FIGURE .A-9 o o S CO UJ cc h- CO o u. o CL CO z UJ Q >-CC a z g ^ CO yd CO ^ 5 o DATE DRILLED imno BORING NO, B-4 GROUND ELEVATION 176'±(MSL) SHEET 1 OF 1 METHOD OF DRILLING 8" Diameter Hollow Stem Auger (Limited Access Rig. CME-75) (Baja) DRIVE WEIGHT 140 lbs, (Auto-Trip Hammer) DROP 30;; SAMPLED BY MJB LOGGED BY MJB REVIEWED BY DESCRIPTION/INTERPRETATION SM FILL: Light brown, damp to moist, medium dense, silty fine SAND; trace clay. 10 I 15 -2a 50/5" 12.0 77.0 9 50/6" 15.1 117.9 SANTIAGO FORMATION: Light grayish brown, damp, weakly cemented, clayey fine- to medium-grained SANDSTONE. Seepage^ ^ _ Light Drown, wet, weaRly to moderately indurateff, clayey SILTSTONE; tracellne sancT; weathered zone. "Grayish brown, moist, weakly cemented^ fine sandy SILTSTONE, Total Depth = 15.5 feet Groundwater not encountered during drilling. Seepage encountered at 7 feet. Backfilled with approximately 3 cubic feet of bentonite grout and patched with asphalt concrete shortly after drilling on 7/21/10. Note: Groundwater, though not encountered at the time of drilling, may rise to a higher level due to seasonal variations in precipitation and several other factors as discussed in the report. BORING LOG VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXT ENSION CARLSBAD, CALIFORNIA PROJECTNO. 106858001 DATE 8/iO FIGURE A-10 Vancouver Lift Station Abandonment and HDD Sewer Extension August 27, 2010 Carlsbad, Califomia ProjectNo. 106858001 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 ex- ploratory excavations 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 Analvsis Gradation analysis tests were performed on selected representative soil samples in general accor- dance with ASTM D 422. The grain-size distribution curves are shown on Figures B-1 and B-2. These test results were utilized in evaluating the soil classifications in accordance with the Uni- fied Soil Classification System (USCS). Direct Shear Tests Direct shear tests were performed on relatively undisturbed samples in general accordance with ASTM D 3080 to evaluate the shear strength characteristics of selected materials. The samples were inundated during shearing to represent adverse field conditions. The results are shown on Figures B-3 and B-4. Soil Corrosivity Tests Soil pH, and resistivity tests were performed on representative samples in general accordance with Califomia Test (CT) 643. The soluble sulfate and chloride content of selected samples were evaluated in general accordance with CT 417 and CT 422, respectively. The test results are pre- sented on Figure B-5. I06S5SO0I R.doc GRAVEL SAND FINES Coarse Fine Coarse Medium Fine Silt Clay U.S. STANDARD SIEVE NUMBERS M/r 1" 3/4" 1/2" 3/8" 4 8 16 30 50 100 200 HYDROMETER 100 90 80 1- 70 I O ^ 60 >-m S 50 z LL ^ 40 UJ CJ a: u> 30 20 10 0 GRAIN SIZE IN MILLIMETERS Symbol Hole No. Depth (ft) Liquid Limit Plastic Limit Plasticity Index Dio D30 Deo Cc Passing No, 200 (%) U.S.C.S • B-1 1.0-5.0 --------23 SC PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422 GRADATION TEST RESULTS FIGURE B-1 PROJECT NO, DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-1 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-1 loeasaool SIB/EI B-I Q I.OSO XIS GRAVEL SAND FINES Coarse Fine Coarse Medium Fine Silt Clay U.S. STANDARD SIEVE NUMBERS 3" 1-1/2" 1" 3/4" 1/2' 3/8" 4 8 16 30 50 100 200 HYDROMETER 1 i 1 i 1 1 1 1 1 1 1 L i . 1 1 1 1 \, 1 1 1 1 L i . 1 1 1 1 1 \ 1 1 1 1 1 1 1 1 1 I 1 j 1 1 1 i 1 1 1 1 1 i 1 1 1 1 1 1 1 1 GRAIN SIZE IN MILLIMETERS Symbol Hole No. Depth (ft) Liquid Limit Plastic Umit Plasticity Index Dio D30 Deo Cu Cc Passing No. 200 (%) U.S.C.S • B-4 0,0-5.0 -------45 SM PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422 GRADATION TEST RESULTS FIGURE B-2 PROJECT NO. DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-2 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-2 106658001 SIEVE1 B-4 (g 0.0-5,0-Xls 4000 3000 iL. CO a CO CO Lii DC I-CO IT I CO 2000 1000 0 0 1000 i ' i • 2000 3000 NORMAL STRESS (PSF) 400'0 Description Symbol Sample Location Depth (ft) Shear Strength Cohesion, c (psf) Friction Angle, ^ (degrees) Soil Type Clayey SAND B-1 5.0-6.5 Peak 1,120 22 SC Clayey SAND B-1 5.0-6.5 Peak 1,120 22 SC Clayey SAND - -X - -B-1 5.0-6.5 Ultimate 1,120 21 SC PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 3080 DIRECT SHEAR TEST RESULTS FIGURE B-3 PROJECT NO. DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-3 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-3 106858001 SHEAR B-1 @ 5 0-6 5 xls 4000 3000 LL CO CO CO UJ I-co VC < LU X CO 2000 1000 1000 2000 3000 NORMAL STRESS (PSF) 4000 Description Symbol Sample Location Depth (ft) Shear Strength Cohesion, c (psf) Friction Angle, <j) (degrees) Soil Type Clayey SANDSTONE B-4 5,0-5.4 Peak 270 29 Formation Clayey SANDSTONE B-4 5,0-5.4 Peak 270 29 Formation Clayey SANDSTONE - -X - -B-4 5,0-5.4 Ultimate 270 27 Formation PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 3080 DIRECT SHEAR TEST RESULTS FIGURE B-4 PROJECT NO, DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-4 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-4 106858001 SHEAR B-1 Ig 5.0-5 4 xls SAMPLE LOCATION SAMPLE DEPTH (FT) RESISTIVITY ' (Ohm-cm) SULFATE CONTENT' (ppm) (%) CHLORIDE CONTENT' (ppm) B-1 B-4 20.0-21.5 0.0-5.0 7.9 7.9 550 600 610 580 0.061 0.058 360 460 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 643 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 417 PERFORMED IN GENEFIAL ACCORDANCE WITH CALIFORNIA TEST METHOD 422 CORROSIVITY TEST RESULTS FIGURE B-5 PROJECT NO. DATE VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-5 106858001 8/10 VANCOUVER LIFT STATION ABANDONMENT AND HDD SEWER EXTENSION CARLSBAD, CALIFORNIA FIGURE B-5 106858001 CORROSIVITY Page 1.xts