GEOTECHNICAL EVALUATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY, AND CHULA VISTA, CALIFORNIA

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1 GEOTECHNICAL EVALUATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY, AND CHULA VISTA, CALIFORNIA PREPARED FOR: Kimley-Horn and Associates, Inc. 401 B Street San Diego, California PREPARED BY: Ninyo & Moore Geotechnical and Environmental Sciences Consultants 5710 Ruffin Road San Diego, California March 3, 2011 Project No

2 March 3, 2011 Project No Mr. Anthony Podegracz, P.E. Kimley-Horn and Associates, Inc. 401 B Street San Diego, California Subject: Geotechnical Evaluation Blue LRT Station Improvements San Diego, National City, and Chula Vista, California Dear Mr. Podegracz: In accordance with your request and authorization, we have performed a geotechnical evaluation for the Blue Line LRT Station Improvements project in San Diego, National City, and Chula Vista, California. The purpose of this evaluation was to provide recommendations regarding the geotechnical aspects for design and construction of the project. This report presents our findings, conclusions, and recommendations for the proposed project. We appreciate the opportunity to be of service on this project. Respectfully submitted, NINYO & MOORE Chet E. Robinson, P.E., G.E. Senior Project Engineer Soumitra Guha, Ph.D., G.E. Principal Engineer Jonathan Goodmacher, C.E.G. Manager/Principal Geologist CER/SG/JG/gg Distribution: (1) Addressee (via ) (1) Mr. Mark Bishop; Kimley-Horn and Associates, Inc. (via )

3 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No TABLE OF CONTENTS Page 1. INTRODUCTION SCOPE OF SERVICES PROJECT DESCRIPTION AND PROPOSED IMPROVEMENTS SUBSURFACE EXPLORATION AND LABORATORY TESTING GEOLOGY AND SUBSURFACE CONDITIONS Regional Geologic Setting Site Geology Fill Alluvium Old Paralic Deposits Groundwater CONCLUSIONS RECOMMENDATIONS Earthwork and Site Preparation Site Preparation Remedial Grading Temporary Excavations Compacted Fill Fill Soils Slopes Slabs-on-Grade Shelter Foundations Seismic Design Parameters Retaining Walls Soldier Pile and Lagging Walls Track Reconstruction Pavements Soil Corrosivity Concrete Site Drainage Construction Observation and Testing LIMITATIONS REFERENCES R Blue Line.doc i

4 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Tables Table 1 Planned Improvements along the Blue Line...2 Table 2 GPS Locations of Borings...3 Table 3 Depth to Groundwater as Encountered During Drilling...6 Table 4 Recommended CIDH Pier Depths for Shelter Foundations...12 Table 5 Recommended Parameters for Brom s Method...13 Table 6 Seismic Design Factors: Barrio Logan to Bayfront/E Street Stations...14 Table 7 Seismic Design Factors: H Street to Beyer Boulevard Stations...14 Table 8 R-Value Test Results...20 Figures Figure 1 Project Location Figure 2A Boring Locations - Barrio Logan Station Figure 2B Boring Locations - Pacific Fleet Station Figure 2C Boring Locations - 8th Street Station Figure 2D Boring Locations - 24th Street Station Figure 2E Boring Locations - Bayfront/E Street Station Figure 2F Boring Locations - H Street Station Figure 2G Boring Locations - Palomar Street Station Figure 2H Boring Locations - Palm Avenue Station Figure 2I Boring Locations - Iris Avenue Station Figure 2J Boring Locations - Beyer Boulevard Station Figure 3 Lateral Earth Pressures for Yielding Retaining Walls Figure 4 Lateral Earth Pressures for Restrained Retaining Walls Figure 5 Retaining Wall Drainage Detail Figure 6 Lateral Earth Pressures for Soldier Pile Walls Appendices Appendix A Boring Logs Appendix B Laboratory Testing Appendix C Input Parameters for Lateral Pile Capacity Analysis Appendix D Kimley-Horn Review Comments R Blue Line.doc ii

5 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No INTRODUCTION In accordance with your request and authorization, Ninyo & Moore has performed a geotechnical evaluation for the Blue Line Light Rail Transit (LRT) Station Improvements project, in San Diego, National City, and Chula Vista, California (Figure 1). This report presents data from our background, field, and laboratory evaluations, provides conclusions regarding the geotechnical conditions at the sites, and provides geotechnical recommendations for the design and construction of the project. During drilling at the Harborside station, potentially contaminated materials were encountered. The borings were abandoned. A separate geotechnical evaluation will be conducted at a later date. Recommendations for the Harborside station are not included in this report. Incorporated into this report are responses to review comments received from Kimley-Horn following review of a draft version of this report. The Kimley-Horn review comments form is included in Appendix D of this report. 2. SCOPE OF SERVICES Our scope of services included the following: Review background information including readily available geotechnical reports, geologic maps, utility maps, stereoscopic aerial photographs, documents provided by Kimley-Horn and Associates, Inc. (Kimley-Horn), and in-house data. Perform a field reconnaissance of each station to observe and document current conditions. Coordinate with Metropolitan Transit System (MTS) and Kimley-Horn to identify suitable locations for our subsurface explorations. Obtain a Right of Entry permit from MTS. Obtain boring permits, as required, from the County of San Diego Department of Environmental Health (DEH). Notify Underground Service Alert of the subsurface exploration and retain a private utility locator to clear proposed boring locations of potential conflicts with underground utilities. Core the concrete platform slabs to allow drilling of exploratory borings R Blue Line.doc 1

6 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Log and sample 24 exploratory borings using limited-access drill rigs and manual methods. Obtain and transport bulk and relatively undisturbed samples from the borings to our inhouse geotechnical laboratory for analysis. Perform geotechnical laboratory testing on selected samples from the exploratory borings. Compile and perform an engineering analysis of the data obtained. Prepare this report presenting our findings and conclusions regarding geotechnical conditions at each of the stations, and providing geotechnical recommendations regarding the proposed construction. 3. PROJECT DESCRIPTION AND PROPOSED IMPROVEMENTS The project is composed of 11 LRT stations along the current Blue Line route. The stations in this evaluation included the Barrio Logan, Harborside, Pacific Fleet, 8th Street, 24th Street, Bayfront/E Street, H Street, Palomar Street, Palm Avenue, Iris Avenue, and Beyer Boulevard LRT stations. The locations are active trolley stations. They generally consist of concrete slabs or asphalt pavements abutting the tracks for the loading and unloading of passengers. Other improvements include underground utilities, retaining walls, tree wells, and shelters. The station platforms are generally flat. We understand that the proposed improvements to the platforms will include the construction of new shelters supported on cast-in-drilled-hole (CIDH) foundations and raising of the platforms to allow direct access into new trolley cars. Additional station improvements will include the construction of new retaining walls and re-paving of selected parking lots. A summary of the improvements at the various stations is provided in Table 1. Table 1 Planned Improvements along the Blue Line LRT Station Raise Platforms New Shelters Retaining Walls Pavements Barrio Logan X X Harborside X X X Pacific Fleet X X X 8th Street X X X 24th Street X X X Bayfront/E Street X X X R Blue Line.doc 2

7 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No LRT Station Table 1 Planned Improvements along the Blue Line Raise Platforms New Shelters Retaining Walls Pavements H Street X X X X Palomar Street X X X X Palm Avenue X X X Iris Avenue X X X Beyer Boulevard X X X X 4. SUBSURFACE EXPLORATION AND LABORATORY TESTING Our subsurface exploration consisted of the excavation, logging, and sampling of 24 smalldiameter borings. 26 borings (B-1 through B-26) were designated to be drilled for this project; however, borings B-3 and B-4 at the Harborside station were deleted due to environmental issues. To maintain consistency with permits, the originally designated numbering was retained. The borings were drilled to depths of up to approximately 16½ feet below the existing ground surface, with limited-access drill rigs and manual methods. The borings were advanced through the existing concrete slabs or asphalt pavements using a concrete coring machine with a diamond tip core barrel. Relatively undisturbed, modified split-barrel drive samples and bulk soil samples were obtained from the borings. The samples were transported to our in-house geotechnical laboratory for testing. The excavations were backfilled in general accordance with the San Diego County DEH standards. Logs of the borings are included in Appendix A. The approximate locations of the borings are shown on Figures 2A through 2J. The locations of the borings were recorded with a Trimble GeoXH 2005 Series GPS receiver. The latitude and longitude of the borings are presented in Table 2. Table 2 GPS Locations of Borings Station Boring Latitude Longitude Barrio Logan Station B Barrio Logan Station B Pacific Fleet Station B Pacific Fleet Station B th Street Station B th Street Station B th Street Station B th Street Station B R Blue Line.doc 3

8 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Table 2 GPS Locations of Borings Station Boring Latitude Longitude 24th Street Station B Bayfront/E Street Station B Bayfront/E Street Station B H Street Station B H Street Station B H Street Station B Palomar Street Station B Palomar Street Station B Palm Avenue Station B Palm Avenue Station B Iris Avenue Station B Iris Avenue Station B Beyer Boulevard Station B Beyer Boulevard Station B Beyer Boulevard Station B Beyer Boulevard Station B Geotechnical laboratory testing of representative soil samples obtained during our subsurface exploration included in-situ moisture content and dry density, gradation, Atterberg limits, direct shear, expansion index, corrosivity, and R-value. The laboratory tests were performed in our inhouse laboratory. The results of the in-situ moisture content and dry density tests are shown at the corresponding sample depths on the boring logs in Appendix A. The results of the other laboratory tests performed are presented in Appendix B. 5. GEOLOGY AND SUBSURFACE CONDITIONS Our findings regarding regional and site geology, and groundwater conditions are provided in the following sections Regional Geologic Setting The project is situated in the western San Diego County section 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 (Harden, 1998; Norris and Webb, 1990). The province varies in width from approximately 30 to 100 miles. In general, the province consists of rugged R Blue Line.doc 4

9 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No mountains underlain by Jurassic metavolcanic and metasedimentary rocks, and Cretaceous igneous rocks of the southern California batholith. The portion of the province in San Diego County that includes the project area consists generally of uplifted and dissected Eocene-age and Quaternary-age sedimentary rocks. The Peninsular Ranges Province is traversed by a group of sub-parallel faults and fault zones trending roughly northwest. Several of these faults are considered active faults. The Elsinore, San Jacinto, and San Andreas faults are active fault systems located northeast of the project area and the Coronado Bank, San Diego Trough, San Clemente, and Rose Canyon faults are active faults located west of the project area. Major tectonic activity associated with these and other faults within this regional tectonic framework consists primarily of right-lateral, strike-slip movement Site Geology Earth units encountered during our subsurface evaluation included fill, alluvium, and old paralic deposits. Additional descriptions of the earth units encountered are provided on the boring logs in Appendix A, and generalized descriptions are provided in the subsequent sections Fill Fill materials were encountered in our exploratory borings to depths of up to approximately 14 feet below the existing ground surface. Depending on the station, the fill material generally consisted of damp to wet, loose to dense, silty sand, silty gravel, clayey sand, sandy silt, and firm to very stiff, sandy clay and silty clay, with fine to coarse gravel and cobbles. Scattered debris and roots were encountered in the fill Alluvium Alluvium was encountered beneath the fill at the Pacific Fleet, 24th Street, and H Street stations and extended to the bottom of the borings. The alluvium material generally consisted of brown, reddish brown, and dark brown, damp to saturated, medium dense R Blue Line.doc 5

10 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No to very dense, silty sand, clayey sand, and very stiff to hard, sandy clay, silty clay with fine to coarse gravel and cobbles Old Paralic Deposits Old paralic deposits were encountered beneath the fill at the Barrio Logan, 8th Street, Bayfront/E Street, Palomar Street, Palm Avenue, Iris Avenue, and Beyer Boulevard stations and extended to the bottom of the borings. As encountered, the old paralic deposits generally consisted of brown, grayish brown, and reddish brown, damp to wet, medium dense to very dense, silty sand, clayey sand, and very stiff to hard, sandy clay, with gravel and cobbles Groundwater Groundwater was encountered in the borings during drilling at the Pacific Fleet and 8th Street stations at approximately mean sea level (MSL). We emphasize that groundwater levels are expected to fluctuate due to seasonal variations and prolonged climatic conditions. Accordingly, higher groundwater levels should be anticipated during construction. For design and construction purposes, the anticipated groundwater conditions at each station are listed in Table 3. The information is based on data provided by the Geotracker website (Geotracker, 2011) and the moisture contents of analyzed samples, Station Table 3 Depth to Groundwater as Encountered During Drilling Approximate Elevation of Platform (feet above MSL) Measured Depth to Groundwater During Drilling (feet) Recommended Design Elevation of Groundwater During Construction (feet above MSL) Barrio Logan Station 25 Not Encountered 19 Pacific Fleet Station th Street Station th Street Station 24 Not Encountered Not Anticipated Bayfront/E Street Station 35 Not Encountered Not Anticipated H Street Station 25 Not Encountered 15 Palomar Street Station 50 Not Encountered 40 Palm Avenue Station 45 Not Encountered Not Anticipated Iris Avenue Station 75 Not Encountered Not Anticipated Beyer Boulevard 105 Not Encountered Not Anticipated R Blue Line.doc 6

11 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No CONCLUSIONS Based on the results of our geotechnical evaluation, it is our opinion that the proposed project is feasible from a geotechnical standpoint, provided that the following recommendations are incorporated into the design and construction of the project. Geotechnical considerations include the following: Depending on location, the stations are underlain by fill, alluvium, and old paralic deposits. The fill is generally not considered suitable in its current state for support of the proposed improvements. Where slabs are removed, remedial grading should be performed to remove loose fill soils and replace them with compacted fill. Excavations in soil layers should be generally feasible with heavy earthmoving equipment in good working order. Debris, gravel, and cobble layers were encountered at several stations, which will present difficult drilling and excavating conditions. Heavy ripping or rock excavation techniques should be anticipated for the site excavations at those locations and coring should be anticipated during installation of the shelter foundations. We anticipate that the earth materials generated from the excavations in soil layers should be generally suitable for use as compacted fill, unless impacted by environmental contamination. Excavations into cobbly soils may generate oversize materials that may not be suitable for use as backfill. Some of the site soils have little cohesion. These materials may be prone to caving in drilled holes and the contractor should anticipate the need to mitigate caving during construction. Deep foundations are planned for the shelters, and consequently groundwater is a design and construction consideration. Our measurements during drilling and evaluation of the moisture contents obtained from the borings indicate that the groundwater will likely be encountered in the excavations for the drilled piers at the Barrio Logan, Pacific Fleet, 8th Street, H Street, and Palomar Street stations. 7. RECOMMENDATIONS Based on our understanding of the project, the following recommendations are provided for the design and construction of the station platforms, retaining walls, shelters, and parking lots. The proposed site improvements should be constructed in accordance with the requirements of the applicable governing agencies. The analyses were conducted based on engineering parameters obtained from our subsurface exploration and geotechnical laboratory testing as well as our professional experience R Blue Line.doc 7

12 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Earthwork and Site Preparation For the various stations, earthwork is anticipated to consist of excavation for pier foundations, and subgrade preparation for the new concrete slabs. Earthwork should be performed in accordance with the requirements of applicable governing agencies and the recommendations presented in the following sections Site Preparation Site preparation should begin with the removal of existing improvements, deleterious matter, tree roots, and other vegetation in areas to receive new concrete slabs. Demolition debris and other unsuitable material generated from on-site operations should be removed off the property. This includes rocks or debris greater than approximately 4 inches in diameter. Underground utilities located within the proposed limits of the construction should be removed or abandoned, capped off or relocated so as not to interfere with earthwork operations Remedial Grading To create a uniform bearing surface for the new slabs, we recommend that the existing fill soils be overexcavated to provide a 2-foot thick zone of compacted fill below the planned grades. To create a uniform bearing surface for parking lot pavements, we recommend that the existing fill soils be overexcavated to provide an 18-inch thick zone of compacted fill below the planned subgrades. The extent and depths of removals should be evaluated by Ninyo & Moore s representative in the field based on the materials exposed. Additional remedial grading may be required depending on the exposed materials. The contractor should take precautionary measures not to damage the existing improvements Temporary Excavations The subsurface soils should generally be excavatable by standard, heavy-duty earthmoving equipment, however, construction debris, cobbles, and hard rock layers were encountered which will be difficult to excavate and require heavy ripping or rock breaking equipment and coring equipment for the shelter foundations R Blue Line.doc 8

13 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No For temporary excavations, we recommend that Occupational Safety and Health Administration (OSHA) Type C soil classification be used. Upon making the excavations, the soil classifications and excavation performance should be evaluated in the field by the contractor in accordance with the OSHA and California Division of Occupational Safety and Health (Cal-OSHA) regulations. Temporary excavations should be constructed in accordance with OSHA and Cal-OSHA recommendations. For trench or other excavations, OSHA and Cal-OSHA requirements regarding personnel safety should be met using appropriate shoring (including trench boxes) or by laying back the slopes to a slope ratio no steeper than 1.5:1 (horizontal to vertical). Excavations encountering groundwater or seepage should be evaluated on a case-by-case basis. On-site safety of personnel is the responsibility of the contractor 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 8 inches and watered or dried, as needed, to achieve moisture contents near the laboratory optimum. The scarified materials should then be compacted to 90 percent of their modified Proctor density as evaluated in accordance with American Society for Testing and Materials (ASTM) test method D The evaluation of compaction by Ninyo & Moore should not be considered to preclude any requirements for observation or approval by governing agencies. 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 should be placed in horizontal lifts of approximately 8 inches in loose thickness. Prior to compaction, each lift should be watered or dried as needed to achieve a moisture content generally near the laboratory optimum, mixed, and then compacted by mechanical methods to 95 percent of its modified Proctor density as evaluated by R Blue Line.doc 9

14 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No ASTM D Successive lifts should be treated in a like manner until the desired finished grades are achieved Fill Soils The soils encountered at the project site should be generally suitable for reuse as fill or backfill provided they are free of organic material, contaminated material, clay lumps, and rocks or debris greater than 4 inches in diameter. Cobbles or rock chunks, if generated during excavation, may be broken into acceptably sized pieces or disposed of off site. Based on the field exploration, the potential for expansive conditions of on-site soils was evaluated to be generally low. However, pockets of expansive materials (expansion index greater than 50) may be encountered. We recommend that expansive materials, if encountered, be removed from the site. Potential fill soil imported to the site should consist of granular material with a low potential for expansion as evaluated by ASTM D 4829 and a low corrosivity potential. Ninyo & Moore should evaluate materials before importation. Fill and backfill should be compacted to the density recommended herein, and moisture conditioned to a moisture content which is near optimum as evaluated by ASTM D Lift thickness for fill and backfill will depend on the type of compaction equipment used, but fill should generally be placed in lifts not exceeding 8 inches in loose thickness. Earthwork, including removals and recompaction, should be observed by Ninyo & Moore to assess conformance with the recommendations contained in the geotechnical report Slopes Permanent cut slopes should not be steeper than 2:1 (horizontal to vertical). Ninyo & Moore should observe cut slopes during excavation. If excavations for cut slopes expose loose, cohesionless, or otherwise unsuitable materials, overexcavation of the unsuitable material and replacement with a compacted stabilization fill should be evaluated and may be recommended by Ninyo & Moore R Blue Line.doc 10

15 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Permanent fill slopes should not be steeper than 2:1 (horizontal to vertical). Slopes in excess of 20 feet high are not anticipated but should be evaluated on an individual basis should they be needed. When placing fill on slopes steeper than 5:1 (horizontal to vertical), topsoil and other materials deemed unsuitable should be removed. Near-horizontal keys and near-vertical benches should be excavated into firm fill material. Keying and benching requirements should be evaluated by Ninyo & Moore during construction based on the extent of the new fill slopes. Compacted fill slopes should be overbuilt and cut back to grade, exposing firm compacted fill. The actual amount of overbuilding may vary as field conditions dictate. Care should be taken by the contractor to provide mechanical compaction as close to the outer edge of the overbuilt slope surface as practical. Positive drainage should be established away from the top of slope. This may be accomplished using a berm and pad gradient of 2 percent or steeper at the top-of-slope areas. Site runoff should not be permitted to flow over the tops of slopes Slabs-on-Grade The new concrete slabs should be 5 inches thick and reinforced with No. 3 steel reinforcing bars placed at 24 inches on center, both ways or as detailed by the project structural engineer. A design modulus of subgrade reaction of 160 pounds per cubic inch (pci) may be used for design of the concrete slabs-on-grade. The reinforcement should be located in the middle one-third of the slab height. We recommend that chairs be utilized to aid in the proper placement of the reinforcement. We recommend that the new slab be connected to the existing slabs with epoxy dowels. Expansion joints and crack control joints should be constructed as detailed by the project structural engineer. Drainage considerations should be incorporated into the new slabs R Blue Line.doc 11

16 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Shelter Foundations The following recommendations provide design criteria for the proposed foundations for the new shelters. Foundations for the shelters 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. Depending on the location, the stations are underlain by fill and native soils consisting of alluvium and old paralic deposits. Due to the variable depth and consistency of the on-site fills, we recommend that the shelter foundations be supported on native alluvial soils or old paralic deposits rather than on fill. We anticipate that CIDH concrete piers will be used for support of the proposed, new shelters. Conceptual drawings of the piers are provided in the project plans by Kimley-Horn (Kimley-Horn, 2010). The various stations are generally underlain by fill over alluvium or old paralic deposits. We recommend that the shelter foundations be embedded 2 feet or more into native soils (i.e., alluvium or old paralic deposits). The recommended pier foundation depths are summarized in Table 4. The piers may be designed using an allowable end bearing capacity of 2,000 pounds per square foot (psf). The weight of the pier may be neglected when evaluating the end bearing. LRT Station Table 4 Recommended CIDH Pier Depths for Shelter Foundations Bearing Material Deepest Observed Depth of Fill (feet) Recommended Pier Length* (feet) Barrio Logan Old Paralic Deposits Pacific Fleet Alluvium th Street Old Paralic Deposits th Street Alluvium Bayfront/E Street Old Paralic Deposits H Street Alluvium Palomar Street Old Paralic Deposits Palm Avenue Old Paralic Deposits Iris Avenue Old Paralic Deposits Beyer Boulevard Old Paralic Deposits Note: *Pier foundation length to provide recommended embedment into bearing soils. Lateral capacity may control actual pier design. Depth of bearing material should be evaluated by Ninyo & Moore during construction R Blue Line.doc 12

17 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No We understand that the lateral capacity of the piles will be evaluated by Kimley-Horn using lateral pile analysis software, Brom s method, or Section of the 2007 California Building Code (CBC). Input parameters for lateral pile analyses are presented in Appendix C. For evaluating the lateral capacity of piles using Brom s method, the parameters in Table 5 may be used in design of the foundations. For evaluating the lateral capacity of piles using Section of the 2007 CBC, an allowable lateral soil bearing pressure (i.e., passive) of 750 psf per foot of depth may be used. LRT Station Table 5 Recommended Parameters for Brom s Method Unit Weight of Soil Internal Friction Angle of Soil (degrees) Passive Soil Pressure (psf per foot of depth)* Barrio Logan (0 to 5.5 ) 32 (5.5 and below) 750 Pacific Fleet th Street (0 to 10 ) 30 (10 and below) th Street Bayfront/E Street (0 to 4 ) 30 (4 and below) 750 H Street (0 to 8 ) 30 (8 and below) 750 Palomar Street Palm Avenue (0 to 1 ) 32 (1 and below) 750 Iris Avenue (0 to 4 ) 30 (4 and below) 750 Beyer Boulevard (0 to 11 ) 30 (11 and below) 750 Note: *The passive soil pressure may be used up to a value of 7,500 psf. Concrete debris, loose soils, cobbles, boulders, and hard rock encountered in the excavations will present difficult drilling conditions. Some of the site soils have little cohesion and caving of drilled holes should be anticipated. The contractor should plan for the difficult drilling conditions and may consider the use of casing or similar techniques to mitigate these conditions Seismic Design Parameters The proposed improvements should be designed in accordance with the requirements of governing jurisdictions and applicable building codes. Tables 6 and 7 present the seismic de R Blue Line.doc 13

18 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No sign parameters for the site in accordance with CBC (2007) guidelines and mapped spectral acceleration parameters (USGS, 2011). Table 6 Seismic Design Factors: Barrio Logan to Bayfront/E Street Stations Factors Barrio Pacific 8th 24th Bayfront/ Logan Fleet Street Street E Street Site Class D D D D D Site Coefficient, F a Site Coefficient, F v Mapped Short Period Spectral Acceleration, S S Mapped One-Second Period Spectral Acceleration, S Period Spectral Acceleration Adjusted For Site Class, S MS One-Second Period Spectral Acceleration Adjusted, S M Design Short Period Spectral Acceleration, S DS Design One-Second Period Spectral Acceleration, S D Long-period Transition Period (ASCE 7, Figure 22-15) Table 7 Seismic Design Factors: H Street to Beyer Boulevard Stations Factors H Street Palomar Palm Iris Beyer Street Avenue Avenue Boulevard Site Class D D D D D Site Coefficient, F a Site Coefficient, F v Mapped Short Period Spectral Acceleration, S S Mapped One-Second Period Spectral Acceleration, S Period Spectral Acceleration Adjusted For Site Class, S MS One-Second Period Spectral Acceleration Adjusted, S M Design Short Period Spectral Acceleration, S DS Design One-Second Period Spectral Acceleration, S D Long-period Transition Period (ASCE 7, Figure 22-15) R Blue Line.doc 14

19 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Retaining Walls We understand that retaining walls are proposed at the Harborside, Pacific Fleet, H Street, Palomar Street, and Beyer Boulevard stations. For the design of retaining walls that are not restrained against movement by rigid corners or structural connections, an active pressure represented by an equivalent fluid unit weight of 40 pounds per cubic foot (pcf) may be used. Restrained walls (non-yielding) may be designed for an at-rest pressure represented by an equivalent fluid unit weight of 60 pcf. These pressures assume low-expansive, level backfill and free draining conditions. Yielding and restrained walls retaining sloping backfill inclined at 2:1 (horizontal to vertical) may be designed using equivalent fluid weights of 64 pcf and 90 pcf, respectively. Wall friction was not considered in our evaluation. Surcharge pressures caused by vehicles or nearby structures are not included. The recommended lateral earth pressure values and considerations applicable for the subject project are summarized on Figures 3 and 4. We understand that the retaining walls do not exceed 12 feet in height, so seismic lateral earth pressures are not required for design of the walls. A drain should be provided behind the retaining wall, and the drain should be connected to an appropriate outlet. Drainage design should incorporate free-draining backfill materials and perforated drains as depicted on Figure 5. The retaining walls may be supported on continuous footings founded in compacted fill, alluvium, or old paralic deposits. The foundations may be designed using an allowable bearing capacity of 2,500 psf. This allowable bearing capacity may be increased by one third when considering loads of a short duration such as wind or seismic forces. Footings should be founded 18 inches below the lowest adjacent grade. Continuous footings should have a width of 18 inches or as detailed by the project structural engineer. For resistance of footings to lateral loads, we recommend an allowable passive pressure of 300 psf per foot of depth be used up to 3,000 psf. This 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. Passive pressures may R Blue Line.doc 15

20 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No be considered after the wall has moved a horizontal distance equal to multiplied by the height of the wall. The passive resistance should be reduced to a value of 240 psf per foot of depth up to 2,400 psf if the wall is only allowed to move a horizontal distance equal to multiplied by the height of the wall. We understand that at the Beyer Boulevard station, a retaining wall is planned within the slope along the southwest side of the platform. The new retaining wall will be constructed along the top of the 2:1 (horizontal to vertical) slope, approximately 12 feet horizontally from an existing retaining wall to the southwest. The foundation for the wall should be deepened to meet the setback requirements of Figure of the 2007 CBC. To resist lateral loads, the passive resistance should be reduced to an allowable passive pressure of 150 psf per foot of depth up to 1,500 psf. For frictional resistance to lateral loads, we recommend that a coefficient of friction of 0.35 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. For retaining walls 4 feet in height or less, we estimate that the proposed foundations, designed and constructed as recommended, will undergo total settlement on the order of 1/2 inch. Differential settlement on the order of 1/4 inch over a horizontal span of 40 feet should be expected. For retaining walls taller than 4 feet, we estimate that the proposed foundations, designed and constructed as recommended, will undergo total settlement on the order of 1 inch. Differential settlement on the order of 1/2 inch over a horizontal span of 40 feet should be expected. Settlements will generally be elastic and should occur relatively quickly Soldier Pile and Lagging Walls We understand that a soldier-pile-and lagging wall will be constructed along the northwest side of the new platform at the Beyer Boulevard station. The soldier-pile-and-lagging walls will consist of wood soldier piles placed in 18-inch-diameter drilled holes with wood lag R Blue Line.doc 16

21 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No ging, or steel H-piles (W 12x53) placed in 24-inch diameter drilled holes with wood or concrete lagging. Wood piles and lagging should be appropriately treated to reduce the potential for deterioration. Concrete lagging should be specified with consideration for the corrosive or deleterious nature of the on-site soil materials. Use of non-corrosive wall backfill material may reduce the potential for sulfate attack on concrete. Soldier-pile-and-lagging walls may be designed for yielding conditions wherein the wall rotates away from the retained soil and the at-rest earth pressures are reduced to active pressures. The movement of the top of the wall to develop active pressures should be about 1/10 of 1 percent of the wall height. Soldier-pile-and-lagging walls should be designed for the active and passive earth pressures presented on Figure 6. Once the depth of embedment and point of rotation are selected to meet static and moment equilibrium at the tip (base) of the soldier pile, the depth of embedment should be increased by 20 to 40 percent for an approximate factor of safety of 1.5 to 2.0, respectively. Soldier piles may be designed for an allowable side friction of 16L pounds per square foot to resist vertical loads where L is the pile embedment length in feet. The soldier piles may be considered to have an effective width (with respect to earth pressures) of 3B, where B is the diameter of the pier, provided that the center-to-center spacing of the soldier piles is equivalent to 3B or wider. An effective pier width equivalent to the pier spacing may be assumed where the center-to-center spacing is less than 3B. On level ground, lagging should be continued to 1 foot below grade at the bottom of the wall. On sloping ground, the lagging should be continued to 1 foot below the point where there is 5 feet of lateral clearance between the wall and the slope face. Passive pressure should be neglected above the bottom of the lagging. The vertical distance from the bottom of the lagging to the grade of the retained soil should be used as the wall height for design purposes. Should granular backfill be used to fill gaps between the cut and the wall, measures should be taken to reduce potential for erosion and loss of the retained soil. Filter fabric (Mirafi 140NC or equivalent) should be placed against the backside of the cut to separate the granu R Blue Line.doc 17

22 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No lar backfill. To reduce discoloration and corrosion attack due to seepage through the wall facing, sealant may be placed between lagging members. Drainage design should incorporate free-draining backfill materials and perforated drains as depicted on Figure 5. Soldier piles should be installed close to the planned location. The soldier piles should not be out of plumb by more than 5 percent over the length of the pile. Furthermore, the top of the pile should be within 3 inches of the design location. Cast-in-drilled-hole soldier piles should be drilled to the specified depth, and the shaft bottom should be cleaned of loose material prior to placing concrete. Excavations may not remain stable for a significant length of time. The contractor should be prepared to use temporary casing or drilling fluid to inhibit the shaft excavation from collapsing. Standing water should be removed from the pier excavation or the concrete should be delivered to the bottom of the excavation, below the water surface, by tremie pipe. Casing, if used, should be removed from the excavation as the concrete is placed. Concrete should be placed in a manner that reduces the potential for segregation of the components. The drilled hole above the placed concrete may need to be backfilled with lean concrete to stabilize the hole while the excavation proceeds and lagging is installed. Ninyo & Moore should be permitted to observe the drilling and construction of the soldier piles to check that the embedment criteria are satisfied, the materials encountered match the design assumptions, and that the appropriate construction procedures were followed. The contractor should take precautionary measures not to damage adjacent structures during construction of the retaining walls. Monitoring of structures on the site and on adjoining properties should be performed before, during, and after construction of the retaining walls. If significant movement is observed, the construction should be re-evaluated to reduce the potential for movement Track Reconstruction We understand that the Blue Line LRT Station Improvements project includes reconstruction of the track structural section at each of the stations. We understand that the existing rail lines and ballast will be removed and replaced with new tracks, ties, ballast, and subballast R Blue Line.doc 18

23 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Once the existing ballast and subballast are removed, the contractor should request an evaluation of the exposed ground surface by Ninyo & Moore. Loose or soft soils should be removed, and the exposed subgrade should be moisture conditioned to near its optimum moisture content and compacted to 95 percent of its modified Proctor density as evaluated by ASTM D1557. The evaluation and compaction of the subgrade is needed to mitigate loose materials that may exist beneath the tracks or have been disturbed during removal of the ballast. To expedite the remedial grading of loose materials beneath the tracks, a geogrid, such as a Tensar BX 1100 or equivalent, may be used to stabilize the subgrade before placing ballast rock. Use of the geogrid should be evaluated on a case-by-case basis as the subgrade is exposed. While loose conditions may occur at each of the stations, the probability for encountering a yielding subgrade is higher at the 8th Street station where the borings encountered loose sands, the 24th Street, Bayfront/E Street, and H Street stations where the subgrade material is primarily clayey in nature, and the Palomar Street station where debris was encountered in the existing fill. If the existing ballast is thicker than the planned excavations, the remaining ballast rock may be left in place as the subgrade for the new tracks. Loose material should be removed, and the exposed subgrade should be compacted to a dense, unyielding state. To separate the subgrade soils from the open ballast, the ballast should be underlain by a nonwoven geotextile fabric (such as a Mirafi S1600 or equivalent) with a weight of 16 ounces per square yard. The geotextile fabric should be placed upon the compacted subgrade, and the contractor should take precautionary measures not to damage the fabric. Overlap of the fabric between rolls should be 24 inches. If existing ballast rock is not fully removed during site excavations, the filter fabric should be placed between the existing materials and the new ballast after it is compacted as recommended above R Blue Line.doc 19

24 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Pavements We understand that the parking lots will be rehabilitated at the 8th Street, 24th Street, Bayfront/E Street, H Street, Palomar Street, Palm Avenue, Iris Avenue, and Beyer Boulevard stations. At your request, we tested the subgrade soils at selected stations for R-value to assist Kimley-Horn with the design of the new pavements. The subgrade soils encountered in the borings are listed in Table 8 along with the R-Value for pavement design. R-Value testing is summarized on Figure B-32 in Appendix B. Variations in the subgrade conditions should be anticipated, and final pavement sections should be based on the R-value of the subgrade materials exposed at the time of construction. Table 8 R-Value Test Results Station Boring Soil Type R-Value 8th Street B-8 Clayey Sand 15* 24th Street B-10 Silty Sand 44 Bayfront/E Street B-12 Silty Clay 10* H Street B-14 Sandy Clay 12 Palomar Street B-17 Clayey Sand 17 Palm Avenue B-20 Clayey Sand 15* Iris Avenue B-21 Silty Sand 44 Beyer Boulevard B-23 Clayey Sand 17 *Recommended R-Value based on Soil Type 7.9. Soil Corrosivity Laboratory testing was performed on samples of the on-site soils to evaluate ph and electrical resistivity, as well as chloride and sulfate contents. The ph and electrical resistivity tests were performed in accordance with California Test (CT) method 643, and the sulfate and chloride tests were performed in accordance with CT 416 and 422, respectively. These laboratory test results are presented in Appendix B. The results of the corrosivity testing indicated that the electrical resistivity of the samples tested ranged from approximately 250 to 4,000 ohm-cm. The soil ph of the samples ranged from 5.5 to 8.5. The chloride content of the tested samples was approximately 85 to 520 parts per million (ppm), and the sulfate content was approximately to percent. Based on Caltrans criteria, the Harborside, Pacific Fleet, 8th Street, Bay R Blue Line.doc 20

25 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No front/e Street, H Street, and Beyer Boulevard stations would be classified as corrosive, which is defined as having soils with more than 500 ppm chlorides, more than 0.20 percent sulfates, a ph of 5.5 or less, or a resistivity of 1,000 ohm-cm or less. We recommend a corrosion engineer be consulted for corrosion sensitive components of the project 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 stated above, the soil samples tested in this evaluation indicated water-soluble sulfate contents of to percent by weight (i.e., about 40 to 300 ppm). According to the American Concrete Institute (ACI) , the potential for sulfate attack is negligible for water-soluble sulfate in soil below 1,000 ppm. However, based on the anticipated variability of the on-site soils and the potential use of reclaimed water, we recommend the use of Type V cement, and concrete with a water-cement ratio no higher than 0.5 by weight for normal weight aggregate concrete and a 28-day compressive strength of 4,000 pounds per square inch (psi). In order to reduce the potential for shrinkage cracks in the concrete during curing, we recommend that for slabs-on-grade, the concrete be placed with a slump in accordance with Table of Section 302.1R of The Manual of Concrete Practice, Floor and Slab Construction, or Table 2.2 of Section 332R in The Manual of Concrete Practice, Guide to Residential Cast-in-Place Concrete Construction. If a higher slump is needed for screening and leveling, a super plasticizer is recommended to achieve the higher slump without changing the required water-to-cement ratio. The slump should be checked periodically at the site prior to concrete placement. We also recommend that crack control joints be provided in slabs in accordance with the recommendations of the structural engineer to reduce the potential for distress due to minor soil movement and concrete shrinkage. We further recommend that concrete cover over reinforcing steel for slabs-on-grade and foundations be in accordance with section of the 2007 CBC. The structural engineer should be consulted for additional concrete specifications R Blue Line.doc 21

26 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Site Drainage Drainage improvements, including subsurface drain lines and graded slopes and swales, should be provided and maintained to convey surface water runoff away from structures and off of pavement surfaces. Surface water should not drain toward the structures or pond adjacent to foundations. Positive drainage is defined as a slope of approximately 2 percent over a distance of about 5 feet Construction Observation and Testing The conclusions and recommendations presented in this report are based on the result of our subsurface evaluation, laboratory testing, our site observations, and our experience with similar materials. If conditions are found to vary from those described in this report, Ninyo & Moore should be notified and additional recommendations will be provided upon request. Ninyo & Moore should be provided the opportunity to review the project plans prior to the start of construction. Ninyo & Moore should perform appropriate observation and testing services during construction operations, including observation of foundation excavations and evaluation of subgrade conditions in areas where flatwork or settlement-sensitive improvements are to be constructed. Ninyo & Moore should also observe and test the placement and compaction of fill soils. The recommendations provided in this report are based on the assumption that Ninyo & Moore will provide geotechnical observation and testing services during construction. In the event that it is decided not to utilize the services of Ninyo & Moore during construction, we request that the selected consultant provide the client with a letter (with a copy to Ninyo & Moore) indicating that they fully understand Ninyo & Moore's recommendations, and that they are in full agreement with the design parameters and recommendations contained in this report. Construction of proposed improvements should be performed by qualified subcontractors utilizing appropriate techniques and construction materials R Blue Line.doc 22

27 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No 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. Please also note that our evaluation was limited to assessment of the geotechnical aspects of the project, and did not include evaluation of structural issues, environmental concerns, or the presence of hazardous materials. 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 ac R Blue Line.doc 23

28 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No 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, conclusions, and/or recommendations of this report by parties other than the client is undertaken at said parties sole risk R Blue Line.doc 24

29 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No REFERENCES American Concrete Institute, 1991a, Guidelines for Concrete Floor and Slab Construction, (ACI 302.1R). American Concrete Institute, 1991b, Guidelines for Residential Cast-in-Place Concrete Construction (ACI 332R). American Concrete Institute (ACI), 2010, ACI Building Code Requirements for Structural Concrete and Commentary. American Railway Engineering and Maintenance-of-way Association (AREMA), 2002, Manual for Railway Engineering. Cao, T., Bryant, W.A., Rowshandel, B., Branum, D., and Wills, C.J., California Geological Survey (CGS), 2003, The Revised 2002 California Probabilistic Seismic Hazard Maps. California Building Standards Commission, 2007, California Building Code, Title 24, Part 2, Volumes 1 and 2: dated June. California Department of Transportation (Caltrans), 2003, Corrosion Guidelines (Version 1.0), Division of Engineering and Testing Services, Corrosion Technology Branch: dated September. California Department of Transportation (Caltrans), 2006a, Standard Plans. California Department of Transportation (Caltrans), 2006b, Standard Specifications. California Department of Transportation (Caltrans), 2008, Highway Design Manual. California Geological Survey (CGS), 2003 Earthquake Fault Zones Map, Point Loma Quadrangle, Scale 1:24,000. California Geological Survey (CGS), 2004, Seismic Shaking Hazards in California, World Wide Web, City of San Diego, 1954, Metropolitan Topographic Survey, Sheet , Scale 1:200. City of San Diego, 1978, Topographic Survey (Orthotopographic), Sheet , Scale 1:2,400. City of San Diego, 2008, Seismic Safety Study, Geologic Hazards and Faults, Grids 2, 6, 13 and 17, Scale 1:9,600. Geotracker, 2011, Google Inc., 2010, Google Earth (Version ) [software], Available from Harden, D.R., 1998, California Geology: Prentice Hall, Inc R Blue Line.doc 25

30 Blue Line LRT Station Improvements March 3, 2011 San Diego, National City, and Chula Vista, California Project No Jennings, C.W., and Bryant, W.A., 2010, Fault Activity Map of California: California Geological Survey, Geologic Data Map Series, Map No. 6, Scale 1:750,000. Kennedy, M.P. and Tan, S.S., 2008, Geologic Map of the San Diego 30 x 60 Quadrangle, California, Regional Geologic Map No. 3, Scale 1:100,000. Kimley-Horn and Associates, Inc. (Kimley-Horn), 2010, Preliminary Engineering, Blue Line Trolley Station Improvements, Contract CIP , San Diego Association of Governments, Sheet Nos. 1 through 66, dated July. Ninyo & Moore, In-house proprietary information. Norris, R.M., and Webb, R.W., 1990, Geology of California, Second Edition: John Wiley & Sons, Inc. Poulos, H. G., and Davis, E. H., 1980, Pile Foundation Analysis and Design: John Wiley & Sons, New York. Prakash, Shamsher and Sharma, Hari D., 1990, Pile Foundations in Engineering Practice: John Wiley & Sons, Inc., New York. Public Works Standards, Inc., 2009, Greenbook, Standard Specifications for Public Works Construction. San Diego Association of Governments (SANDAG), 2009, Design Criteria, Draft: dated September 21. Tan, S.S., Landslide Hazards in the Southern Part of the San Diego Metropolitan Area, San Diego County, California, Landslide Hazards Identification Map No. 33, Scale 1:24,000. Terraserver, 2011, Tokimatsu, K., and Seed, H.B., 1987, Evaluation of Settlements in Sands Due To Earthquake Shaking: Journal of Geotechnical Engineering, Vol. 113, No. GT8, p Treiman, J. A., 1993, The Rose Canyon Fault Zone Southern California: California Geological Survey Open-File Report United States Geological Survey, 1967 (Photorevised 1975), National City Quadrangle, California-Baja California, 7.5-Minute Series (Topographic), Scale 1:24,000. United States Geological Survey, 2011, Ground Motion Parameter Calculator v , World Wide Web, AERIAL PHOTOGRAPHS Source Date Flight Numbers Scale USDA AXN-3M 42, 43, 91, 92, 93, 198 and 199 1:24,000 USDA AXN-14M 108 and 109 1:24, R Blue Line.doc 26

31 BARRIO LOGAN STATION HARBORSIDE STATION PACIFIC FLEET STATION 8TH STREET STATION 24TH STREET STATION BAYFRONT/E STREET STATION H STREET STATION PALOMAR STREET STATION PALM AVENUE STATION IRIS AVENUE STATION BEYER BOULEVARD STATION SOURCE: 2008 Thomas Guide for San Diego County, Street Guide and Directory; Map Rand McNally, R.L.07-S-129 NOTE: ALL DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE SCALE IN FEET 0 3,800 7,600 15,200 fig1_ _sl.mxd AOB PROJECT NO. DATE /11 PROJECT LOCATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY, AND CHULA VISTA, CALIFORNIA FIGURE 1

32 B-1 TD=16.5' B-2 TD=16.5' LEGEND fig2a Blue blm.cdr AOB 0 B-2 TD=16.5' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- BARRIO LOGAN STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2A

33 B-5 TD=16.5' B-6 TD=16.5' LEGEND fig2c Blue blm.cdr AOB 0 B-6 TD=16.5' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- PACIFIC FLEET STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2B

34 B-7 TD=16.5' B-8 TD=16.5' LEGEND fig2c Blue blm.cdr AOB 0 B-8 TD=16.5' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- 8TH STREET STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2C

35 B-9 TD=16.5' B-10 TD=16.5' LEGEND B-11 TD=16.5' fig2d Blue blm.cdr AOB 0 B-11 TD=16.5' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- 24TH STREET STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2D

36 B-12 TD=16.0' B-13 TD=16.0' LEGEND fig2e Blue blm.cdr AOB 0 B-13 TD=16.0' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- BAYFRONT/E STREET STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2E

37 B-14 TD=16.5' B-15 TD=16.5' B-16 TD=16.0' LEGEND fig2f Blue blm.cdr AOB 0 B-16 TD=16.0' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- H STREET STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2F

38 B-17 TD=16.5' B-18 TD=16.5' LEGEND fig2g Blue blm.cdr AOB 0 B-18 TD=16.5' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- PALOMAR STREET STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2G

39 B-19 TD=16.5' B-20 TD=7.0' LEGEND fig2h Blue blm.cdr AOB 0 B-20 TD=7.0' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- PALM AVENUE STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2H

40 B-21 TD=16.5' B-22 TD=15.5' LEGEND fig2i Blue blm.cdr AOB 0 B-22 TD=15.5' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- IRIS AVENUE STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2I

41 B-23 TD=16.5' B-24 TD=15.0' B-26 TD=4.0' B-25 TD=5.0' LEGEND fig2j Blue blm.cdr AOB 0 B-26 TD=4.0' BORING TD=TOTAL DEPTH IN FEET N SCALE IN FEET FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. SOURCE: BLUE LINE TROLLEY STATION IMPROVEMENTS, KIMLEY-HORN AND ASSOCIATES, INC., DATED 7/14/10. PROJECT NO DATE 3/11 BORING LOCATIONS- BEYER BOULEVARD STATION BLUE LINE LRT STATION IMPROVEMENTS SAN DIEGO, NATIONAL CITY AND CHULA VISTA, CALIFORNIA FIGURE 2J