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HomeMy WebLinkAboutSWP272750(1) Consulting Engineers and Geoscientists \�j Geo 1�Engineers 1[a Report Geotechnical Engineering Services Boeing BCAG Headquarters Building 25-20 Boeing Longacres Park Fenton, Washington January 7, 1997 ?j For The Boeing Company G e o E n g i n e e r s File No. 0120-214-06-1130 �9N, Geo li Engineers January 7, 1997 Consulting Engineers and Geoscientists Offices in Washington, Oregon,and Alaska Sverdrup Corporation 600 - 108th Avenue Northeast, #700 Bellevue, Washington 98004 Attention: Mr. James D. Coulter We are pleased to submit ten copies of our report documenting our geotechnical engineering services for the Boeing BCAG Headquarters Building 25-20 project located at the Boeing Longacres Park in Renton, Washington. Our services were accomplished in general accordance with our proposal dated October 22, 1996 and our supplemental budget adjustment letters dated December 4, 1996 and December 6, 1996. We appreciate the opportunity to provide geotechnical services on this interesting project. We are available to meet with the design team to discuss the information presented in this report. Please call if you have any questions, or if you require additional information. Yours very truly, GeoEngineers, Inc. ordon M. Denby, P.E. Principal SDS:GMD:wd Document ID: 0120214\FINALS\REP1 File No. 0120-214-06-1130 GeoEngineers,Inc. 8410 154th Avenue N.E. Redmond,WA 98052 Telephone(206)861-0000 Fax(206)861-6050 Printed on recycled paper. CONTENTS Page No. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 PROJECT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 PURPOSE AND SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 BCAG HEADQUARTERS BUILDING 25-20 2 ROADWAY AND UTILIDOR 3 SITE CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 SURFACE CONDITIONS 3 SUBSURFACE CONDITIONS 4 Explorations 4 Soil Conditions 4 BCAG Site 4 Oaksdale Avenue Southwest 5 Southwest 16th Street and Jackson Avenue Southwest 5 Ground Water Conditions 5 CONCLUSIONS AND RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 GENERAL 6 SEISMIC CONSIDERATIONS 6 Regional Seismicity 6 Liquefaction Potential 7 Effects of Liquefaction 8 Lateral Earth Pressures 8 SITE PREPARATION AND EARTHWORK 8 EROSION CONTROL 10 STRUCTURAL FILL 10 Gradation Requirements 10 Use of On-site Soils 11 Compaction Requirements 11 Fill Settlement 12 FOUNDATION SUPPORT - BCAG BUILDING 13 General 13 Previous Pile Load Tests 13 Axial Pile Capacity 13 Pile Downdrag 14 Lateral Capacity 15 -� General 15 Recommended Design Procedure 15 Pile Settlement 17 Pile Installation 17 FLOOR SLAB SUPPORT 17 FOUNDATION SUPPORT - LIGHTLY LOADED STRUCTURES 18 BURIED STRUCTURES 18 General 18 G e o E n g i n e e r s I File No.012021406-1130/010797 CONTENTS (continued) Page No. Previous Utilidor Construction 19 Foundation Support 19 Lateral and Vertical Stresses 20 Thrust Restraint 21 Buoyancy Design and Waterproofing 21 EXCAVATIONS 21 General 21 Excavations Above Ground Water 21 Excavations Below Ground Water 22 Open-Cut Excavations with Dewatering 22 Shored Excavations 23 PAVEMENTS 24 LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 FIGURES Figure No. Vicinity Map 1 Site Plan - Area B 2 Site Plan - Areas A and C 3 Cross Section A-A' 4 Cross Section B-B' 5 Allowable Axial Pile Capacities for Augercast Piling 6 Lateral Resistance Along Pile Cap Loose Sand Backfill 7 Lateral Resistance along Pile Cap Compacted Granular Backfill 8 Lateral Pile Capacity vs. Deflection 9 Pile Moment vs. Depth 24-inch Diameter Augercast Pile 10 Pile Moment vs. Depth 18-inch Diameter Augercast Pile 11 Pile Moment vs. Depth 24-inch Diameter Augercast Pile 12 Overburden and Lateral Earth Pressures on Buried Structures 13 APPENDICES Pape No. Appendix A - Field Explorations A-1 APPENDIX A FIGURES Figure No. Soil Classification System A-1 Key to Boring Log Symbols A-2 Logs of Borings A-3...A-4 Cone Penetration Tests A-5...A-11 Logs of Test Pits A-12...A-21 G e o E n g i n e e r s 11 File No.012021406-1130/010797 CONTENTS (continued) Paqe No. Appendix B - Laboratory Testing B-1 APPENDIX B FIGURES Figure No. Moisture Content Data B-1 Gradation Curves B-2 Percent Fines Data B-3 Appendix C - Logs of Explorations from Previous Studies G e o E n g i n e e r s W File No.012021406-1130/010797 REPORT GEOTECHNICAL ENGINEERING SERVICES BOEING BCAG HEADQUARTERS BUILDING 25-20 BOEING LONGACRES PARK RENTON, WASHINGTON INTRODUCTION This report presents the results of our geotechnical engineering services for the proposed Boeing BCAG Headquarters Building 25-20 project to be constructed at the Boeing Longacres Park in Renton, Washington. The site is shown relative to surrounding physical features on the Vicinity Map, Figure 1 and the Site Plan, Figures 2 and 3. We previously provided geotechnical engineering services for the Longacres Park site, the results of which are presented in our report dated January 23, 1991. This report addresses the entire 200 acres of the park and the recommendations presented were general in nature due to the unknowns regarding specific building configurations, loads and support requirements and the widely varying soil conditions across the site. We also provided detailed geotechnical engineering services for the CSTC (Customer Service Training Center) development which incorporates the northern 51 acres of the Longacres Park site. The results of our services for the CSTC development are presented in our reports dated December 9, 1991 and February 11, 1992. PROJECT DESCRIPTION Our understanding of the BCAG project is based on discussions with Mr.James Nuerenberg of Boeing, Messrs. James Coulter and Jeff Schutt of Sverdrup, Messrs. Dean Clark and Jim Fair of Loschky Marquardt & Nesholm and Mr. Robert Anderson of Skilling Ward Magnusson Barkshire. We understand that the proposed development will consist of the BCAG Headquarters building located south of the CSTC building, a utilidor to connect the BCAG building with the CSTC building, and roadway improvements including the construction of Oaksdale Avenue Southwest between the CSTC building and Southwest 27th Street and a new roadway intersection at Southwest 16th Street and Jackson Avenue Southwest. The BCAG building will be a five-story, cast-in-place concrete structure. The rectangular- shaped building will be about 200 feet by 350 feet in plan with a total floor area of approximately 350,000 square feet (all five floors). Except for elevator pits, tunnels and vaults, and buried utilities, all new foundation components for the building will be above existing grade. The floor slab surface in the BCAG building will be at Elevation 18.5 (U.S. Geological Survey datum). We understand that a tight construction schedule will not permit preloading at the site. Therefore, the ground floor slab for the BCAG building will be a structural slab supported on piles. Columns and walls for the building will also be pile-supported due to the compressible nature and/or liquefaction potential of the near-surface site soils. We assume that the floor slabs G e o E n g i n e e r s I File No. 0120-214-06-1130/010797 and wall and column footings will be structurally connected. Our understanding of the design loads for the building is based on our discussions with Skilling personnel. We understand that there are three typical column loads ranging from 1275 to 2040 kips. We understand that site grades near the BCAG building will be raised between about 1 to 3 feet. Although fill below the building floor slab is not needed because the structural slab will be pile supported, the contractor will likely place fill in the building areas to eliminate the need for forming below the slab. A buried concrete utilidor will be constructed between the BCAG building and the CSTC building. The utilidor will be about 10 feet wide and will be about 6 to 8 feet below the ground surface. The development will also include construction of new paved parking areas, loading dock areas, and roadway improvements. Loading dock areas, sidewalks and miscellaneous exterior slabs will be concrete. All other paved areas will be asphalt. Roadway improvements planned for the project include construction of Oaksdale Avenue Southwest between the CSTC building and Southwest 27th Street and a new roadway intersection at Southwest 16th Street and Jackson Avenue Southwest. We understand that Oaksdale Avenue will provide access to the site during construction. It is desired to use ATB (asphalt treated base) sections for support of construction equipment during construction and then to pave over the ATB with asphalt concrete to provide final pavement sections. The new roadway intersection at Southwest 16th Street and Jackson Avenue Southwest will be removed and replaced with a new roadway section. A portion of the existing roadway section may be used in the new road construction. PURPOSE AND SCOPE The purpose of our services is to evaluate the subsurface soil and ground water conditions as a basis for developing geotechnical recommendations and design criteria for the site development. Our specific scope of services for the BCAG Headquarters Building 25-20 and for the connecting roadway and utilidor includes the following tasks: BCAG HEADQUARTERS BUILDING 25-20 1. Review existing subsurface information from previous explorations performed at or near the site by our firm and review available subsurface information. 2. Further explore the subsurface conditions by drilling two additional borings to depths of 90 to 95 feet and by performing seven CPT (cone penetration test) probes to depths ranging from 65 to 75 feet. 3. Evaluate pertinent engineering characteristics of the foundation soils from the results of laboratory tests performed on soil samples obtained from the explorations. 4. Provide recommendations for site preparation and earthwork, including assessment of the suitability of on-site soils for use in engineered fills, compaction criteria, and any special construction procedures due to special soil characteristics. G e o E n g i n e e r s 2 File No. 0120-21 4-06-1 1 30/0 1 0797 5. Provide recommendations for foundation support of the building and floor slab using pile foundations, including capacity-penetration relationships for appropriate types of pile foundations, estimated pile settlement, pile installation criteria, and lateral pile capacities. 6. Provide recommendations for support of floor slabs, including whether slabs can be supported on-grade and a value for the modulus of subgrade reaction. 7. Develop recommendations for subgrade or other retaining walls, including design lateral soil pressures, passive pressures, friction coefficients and drainage requirements. 8. Address the seismic considerations for the site including evaluating the potential for liquefaction at the site. 9. Attend up to three meetings with Boeing representatives to discuss the results of our study. ROADWAY AND UTILIDOR 1. Review existing subsurface information from previous explorations performed at or near the site by our firm and review available subsurface information performed by others. 2. Further explore the subsurface conditions by excavating 20 test pits to depth ranging from 8 to 15 feet. 3. Evaluate pertinent engineering characteristics of the foundation soils from the results of laboratory tests performed on soil samples obtained from the explorations. 4. Provide recommendations for site preparation, including assessment of the suitability of on- site soils for use in engineered fills, recommended fill slopes, compaction criteria, and any special construction procedures due to special soil characteristics. 5. Develop recommendations for construction dewatering of subgrade excavations. 6. Provide recommendations for foundation support of the utilidor. 7. Develop recommendations for subsurface walls, including design lateral soil pressures, passive pressures and friction coefficients. 8. Provide recommendations regarding temporary and permanent drainage and erosion control measures. 9. Provide recommendations for pavement design. 10. Attend up to three meetings with Boeing representatives to discuss the results of our study. SITE CONDITIONS SURFACE CONDITIONS The Boeing Longacres Park site is approximately rectangular in shape and situated on the floor of the Green River valley. The BCAG development will be located in the north-central portion of the site, directly south of the existing CSTC development. The BCAG site extends about 600 feet east-west and 650 feet north-south as shown on the Site Plan, Figures 2 and 3. Oaksdale Avenue Southwest will extend north-south through the development. The ground surface at the BCAG site is essentially flat with minor undulations and varies in elevation from about 14 to 18 feet above sea level (U.S. Geological Survey datum). The area G e o E n g i n e e r s 3 File No.0120-214-06-1130/010797 was previously occupied by the main horse barn area. The barn structures have been removed; however, the slabs and foundations remain at the site, together with associated driveways and buried utilities. Vegetation at the site generally consists of tall grass, scattered berry bushes, brush, and large deciduous trees. The existing conditions along proposed Oaksdale Avenue Southwest consists of an approximately 12-foot-wide gravel surfaced roadway with large deciduous trees along the west side and portions of the east side of the roadway. Existing conditions at the intersection at Southwest 16th Street and Jackson Avenue Southwest consist of an existing asphalt concrete driveway and gravel surfaced parking lots. SUBSURFACE CONDITIONS Explorations The subsurface conditions along the site were evaluated based on explorations completed by GeoEngineers for this study and on previous explorations completed by GeoEngineers for the CSTC development. For this study, we completed two borings (13-20 and B-21) to depths of 89 to 94 feet, seven CPT probes (CPT-1 through CPT-6) to depths of 65 to 75 feet, and twenty test pit explorations (TP-3 through TP-22) to depths of 8 to 15 feet. Previous explorations consist of two borings (13-5 and B-8) to depths of 59 feet and one monitoring well (MW-32) to a depth of 20 feet. The locations of all of these explorations are shown on the Site Plan, Figures 2 and 3. A description of the field exploration program completed for this study, together with logs of the explorations, is presented in Appendix A. A description of the laboratory testing program and results of laboratory tests completed on selected samples is presented in Appendix B. The logs of the explorations completed by GeoEngineers for the previous CSTC development are presented in Appendix C. Soil Conditions BCAG Site. The subsurface soils encountered in the explorations are generally uniform across the BCAG site. The near-surface soils generally consist of native soils or a thin layer of fill overlying the native soils. The fill, where present, varies in thickness from a few inches to 4 feet and consists of loose to dense fine to medium sand with varying amounts of silt and gravel. Native soil, consisting of soft to medium stiff silt with occasional fine sand, was encountered at the surface or underlying the fill in all of the explorations. The silt layer generally extends to depths ranging from 6 to 12 feet below the existing ground surface. The silt is underlain by loose to medium dense fine sand with varying amounts of silt and extends to depths ranging from 23 to 30 feet below the existing ground surface. Several 1- to 2-foot-thick layers of soft to medium stiff organic silt were encountered within this sand layer in borings B-20 and B-21 and probes CPT-1, CPT-4 and CPT-7. The loose to medium dense sand is underlain by layers of medium dense to very dense fine to medium sand with occasional gravel, fine to coarse sand with gravel, and fine gravel with sand. The medium dense to very dense sand and gravel below 23 G e o E n g i n e e r s 4 File No. 0120-214-06-1130/010797 to 30 feet is considered to be a suitable bearing layer for support of pile foundations (as discussed in more detail in the "CONCLUSIONS AND RECOMMENDATIONS" section of this report). Two cross sections have been developed to illustrate the generalized subsurface conditions at the BCAG site. These cross sections are presented in Figures 4 and 5. In test pits TP-9 and TP-13, located in the proposed parking area and about 40 feet east of the proposed Oaksdale Avenue Southwest alignment, fill was encountered to depths of 10 feet and 11.5 feet, respectively. The fill consisted of intermixed medium stiff silt and loose to medium dense silty sand. Logs and layers of wood chips were encountered within the fill at these test pit locations. Oaksdale Avenue Southwest. The subsurface conditions along the proposed Oaksdale Avenue Southwest alignment, TP-17 through TP-20, generally encountered 1 to 2.5 feet of fill consisting of loose to medium dense silty fine to medium sand with occasional gravel and crushed rock. The fill is underlain by native soft to medium stiff silt to depths of 6.5 to 9 feet below the ground surface. The underlying soils consist of loose to medium dense sand with varying amounts of silt. The test pits were completed in this sand layer at depths of 8.5 to 12.5 feet below the ground surface. Southwest 16th Street and Jackson Avenue Southwest. The subsurface conditions encountered at the proposed intersection of Southwest 16th Street and Jackson Avenue Southwest, TP-21 and TV-22, consist of 1.5 feet of dense silty sand, crushed rock and quarry spall fill underlain by soft to medium stiff silt to a depth of about 7 feet. The underlying soils consist of loose to medium dense silty fine sand to the full depth of the explorations. Ground Water Conditions Ground water was encountered in the explorations at depths ranging from 5 to 9 feet below the ground surface. This corresponds to approximately Elevation +7 to +10 feet. We expect that the ground water levels in the vicinity of the site will fluctuate as a function of season, precipitation, water levels in the Green River located about 3,000 feet west of the site, and differences in shallow soil conditions which influence ground water movement. GeoEngineers monitored ground water levels at the Longacres Park property during our previous studies at the site. Ground water level information was collected from a series of monitoring wells during the period of January 4, 1991 to October 16, 1992. This information, along with the ground water levels encountered during this study, was used in our analyses for design and construction of buried structures presented in a following section of this report. G e o E n g i n e e r s 5 File No. 0120-214-06-1130/010797 CONCLUSIONS AND RECOMMENDATIONS GENERAL It is our opinion that building foundations and structural slabs can be adequately supported on augercast piles embedded in the medium dense to very dense sand and gravel layers underlying the site. The allowable pile capacity will be dependant on the pile size and diameter. We have developed recommendations for 14-inch, 18-inch, and 24-inch-diameter augercast piles. Lateral forces can be resisted by a combination of the passive soil earth pressures along pile caps and grade beams and the lateral capacity of the vertical piles below the pile caps. Detailed recommendations for pile foundations are discussed below. The utilidor can be supported on-grade provided that a stable native subgrade is achieved and a minimum of 12 inches of compacted structural fill or crushed rock is placed as a base. A larger thickness of base will be required where soft or loose subgrade conditions are encountered. We expect that ground water levels will be at or slightly below the base of the excavation for the utilidor. We expect that if ground water is encountered during construction, it can be controlled through the use of temporary sump pumps. Specific geotechnical recommendations for the proposed BCAG Headquarters Building 25-20 are presented in the subsequent sections of this report. The following areas are addressed: • Seismic Considerations • Site Preparation and Earthwork • Erosion Control • Structural Fill • Foundation Support - BCAG Building • Floor Slab Support • Foundation Support - Lightly Loaded Structures • Buried Structures • Excavations • Pavements SEISMIC CONSIDERATIONS Regional Seismicity The Puget Sound region is seismically active and lies within Seismic Risk Zone 3 with a Seismic Zone Factor (Z) of 0.30 as classified by the Uniform Building Code (ICBO 1994). Based on the results of our explorations, it is our opinion that the soil profile may be characterized using Soil Profile Type S3, as defined in the Uniform Building Code. This profile type consists of "a soil profile containing more than 20 feet of soft to medium stiff clay, but not more than 40 feet of soft clay." This soil profile results in a site factor equal to 1.5. Seismicity in this region is attributed primarily to the interaction between the Pacific, Juan de Fuca and North American plates. The Juan de Fuca plate is subducting beneath the North American Plate. Each year, 1,000 to 2,000 earthquakes occur in Oregon and Washington. G e o E n g i n e e r s 6 File No. 0120-214-06-1130/010797 However, only 5 to 20 of these are typically felt because the majority of recorded earthquakes are smaller than magnitude 3. In recent years, two large earthquakes occurred which resulted in some liquefaction in loose alluvial deposits and significant damage to some structures. The first earthquake, which was centered in the Olympia area about 50 miles from Longacres, occurred in 1949 with a Richter magnitude of 7.1. The second earthquake occurred in 1965 and was centered between Seattle and Tacoma, only a few miles from Longacres, and had a Richter magnitude of 6.5. Seismic hazards from earthquakes include ground shaking, ground rupture from lateral spreading and surface fault rupture, liquefaction, and landslides. Because of the thickness of the Quaternary sediments below the site, the potential for surface fault rupture is considered very remote. However, the underlying subsurface soils indicate that liquefaction is a strong possibility. Evaluation of the potential for damage from an earthquake at a site can be accomplished either through the procedure presented in the UBC or by evaluating a site's specific response spectra for different probabilities of exceedance. A site specific seismic response study was previously completed by GeoEngineers, the results of which were presented in our "Report, Supplemental Geotechnical Engineering Services - Seismic Response Spectra, Boeing Longacres Park, Renton, Washington" dated March 26, 1991. Liquefaction Potential Liquefaction refers to a condition where vibration or shaking of the ground, usually from earthquake forces, results in development of excess pore pressures in saturated soils and subsequent loss of strength in the deposit of soil so affected. In general, soils which are susceptible to liquefaction include loose to medium dense clean to silty sands which are below the water table. The evaluation of liquefaction potential is complex and is dependent on numerous site parameters, including soil grain size, soil density, site geometry, static stresses, and the design ground acceleration. Typically, the liquefaction potential of a site is evaluated by comparing the cyclic shear stress ratio (the ratio of the cyclic shear stress to the initial effective overburden stress) induced by an earthquake to the cyclic shear stress ratio required to cause liquefaction. The cyclic shear stress ratio required to cause liquefaction was estimated using an empirical procedure based on blow count data obtained during sampling in the borings. This method relates the cyclic shear stress ratio required to cause liquefaction to the blow count value and the fines content of the soil. We have evaluated the earthquake-induced cyclic shear stress ratio at this site using an empirical relationship developed by researchers for this purpose. Our analysis indicates that the loose to medium dense sand which underlies the site to a depth of 23 to 30 feet has a moderate to high risk of liquefying under a magnitude 7.5 design earthquake with a horizontal ground acceleration of 0.15g. The underlying medium dense to very dense sand and gravel has a lower potential for liquefaction. G e o E n g i n e e r s 7 File No.0 1 20-2 1 4-06-1 1 30/0 1 0797 Effects of Liquefaction The effects of liquefaction are twofold: First, liquefaction usually results in loss of bearing capacity and resulting settlement of structures which are not pile-supported. Second, liquefaction may result in reduction of lateral support for structures supported on piles. Since most of the building foundation components, including the floor slabs, will be supported on piling bearing in medium dense to very dense sand with a low liquefaction potential, we do not anticipate significant settlement of the buildings during a design seismic event. However, some minor differential settlement between columns is possible. Loss of lateral support for pile foundations can occur where zones of soil liquefy. However, the near-surface stiff silt layer and the lower medium dense sand are not expected to liquefy to any significant extent and should provide adequate lateral support of piles during an earthquake. The potential loss of soil support in the loose sand zones encountered to depths of 23 to 30 feet at this site have been considered in development of our lateral pile recommendations presented in a subsequent section of this report entitled "FOUNDATION SUPPORT-BCAG BUILDING." Structures such as utilities or outside walkways which are supported on-grade will probably experience differential settlement during a design seismic event. The amount of settlement is difficult to estimate because of the complexity of conditions which cause liquefaction. A very rough estimate of differential settlement ranges from less than 1 inch to several inches over a 50- foot distance. Some cracking and/or structural damage may be experienced by structures supported on-grade as a result of liquefaction induced settlement. It is important that the project designers and Boeing either accept this risk or support settlement-sensitive structures on piles. Lateral Earth Pressures An increase in lateral earth pressures on buried structures will occur during seismic shaking. We have included recommendations for increased lateral earth pressures due to seismic shaking in subsequent sections of this report entitled "BURIED STRUCTURES." SITE PREPARATION AND EARTHWORK We recommend that all existing vegetation, major tree root systems, concrete slabs and footings, debris and other obstructions be removed from proposed building and pavement areas. Existing abandoned buried pipe, if present, should either be removed or left in place and filled with a sand or lean grout slurry. Existing asphalt pavements can be left in place to provide a working surface for fill placement where planned finish grades will permit. We recommend in the "PAVEMENTS" section of this report that all pavements be underlain by a minimum of 12 inches of sand and gravel to promote drainage and provide adequate support. Where new pavements are planned, final grades should be compared with existing grades to verify that there will be sufficient clearance to place 12 inches of structural fill over the existing asphalt. The existing asphalt should be removed in areas where the clearance is not adequate. Also, existing asphalt may need to be removed where shallow utilities are planned. Where grading permits, new fill can be placed directly over the asphalt. We do not expect that excavations and pile G e o E n g i n e e r s 8 File No. 01 20-2 14-06-1 13 0/0 1 0797 installation will be affected by the presence of asphalt. Any existing foundations or other embedded elements should be removed if they will interfere with pile or new utility installations. We recommend obstructions be removed to a minimum depth of 3 feet below planned finish floor or pavement grades. For existing undeveloped areas, we recommend that all brush and other debris be removed. Tree roots larger than 2 inches in diameter should be grubbed from the building site. Where less than 2 feet of new structural fill is anticipated in settlement-sensitive areas (e.g., shallow foundation and pavement areas) we recommend that any grass and sod mat be stripped by carefully scraping off the ground surface using a motor patrol grader or similar equipment. Where site grades will be raised by more than 2 feet with structural fill or in areas where pile- supported structural floor slabs are planned, we recommend that the grass and lowlying vegetation be trimmed close to the ground surface and the cuttings wasted off-site prior to placing fill. Where the new pavement and sidewalk grades will be less than 3 feet above existing grades and where shallow foundations are planned, we recommend that the exposed subgrades be evaluated by thorough proofrolling with heavy rubber-tired construction equipment (dry weather construction) or by probing (wet weather construction). During dry weather, we recommend that all loose, soft or otherwise unsuitable areas be compacted with a heavy roller such that the surface is firm and unyielding. If the subgrade cannot be adequately compacted or if the work is performed during wet weather, all soft or loose zones should be removed and replaced with structural fill to the depth determined by the geotechnical engineer at that time. Geotextile fabric may be necessary to aid in stabilizing some areas. The need, specifications and use of fabric should also be determined by a representative of GeoEngineers during construction. We understand that the building, including floor slabs, will be pile-supported. We anticipate that the contractor will choose to place fill in these areas so that concrete for the structural floor slabs, grade beams, pile caps and other pile-supported components can be poured on soil rather than forms. Site preparation in these areas need only be sufficient to support construction equipment during foundation installation. Filter fabric is not recommended in areas where subsequent pile installation is planned because of difficulty in drilling through fabric. Instead, we recommend that in areas where subgrade conditions are such that movement of pile driving equipment is difficult or impossible, a thicker layer (e.g., 2 feet or more) of quality fill (clean sand and gravel) be used. This layer can be graded down to the bottom of the floor slab elevation after the piles are installed. The existing fill and surficial native soils at the site contain a large percentage of fines (silt). These soils are moisture-sensitive and will become soft when wet and disturbed. We recommend that, if practical, site preparation and earthwork be performed during the normally drier months when the surficial soils will provide better support for construction equipment. Even during the driest season, rain can cause significant construction delay if earthwork is required in soils containing a large percentage of fines. G e o E n g i nee r s 9 File No. 0120-214-06-1130/010797 If site preparation is accomplished during wet weather, no attempt should be made to compact or proofroll the surface. These activities would cause softening and rutting which could require extensive repair. All construction activities during wet weather should be done from (or on) access roads and layout areas which are constructed using temporary pads consisting of 18 to 24 inches of quarry spalls, gravel or clean pit run. As previously mentioned, geotextile fabric can aid wet weather earthwork construction significantly in areas where piles are not planned. The use of ATB (asphalt treated base) for construction access roads and layout areas could also be considered. Specific recommendations for use of ATB section are presented in the "PAVEMENTS" section of this report. EROSION CONTROL Control of off-site transport of sediment will be an important environmental protective constraint. In our opinion, conventional erosion/ sedimentation practices will be appropriate. Adequate design of the erosion control system, including redundancy, will be essential together with competent installation and maintenance for the system to function acceptably. We strongly recommend that erosion control measures be installed prior to site grading activities and that monitoring and repairs be made a part of the contractor's agreement. The goal of erosion/sedimentation control system design must be to(1) prevent mobilization of sediment, and (2) efficiently trap or filter sediment suspended in surface runoff before it can be transported off-site or to on-site critical areas such as wetlands or the pond located at the CSTC site. We recommend that the project grading plans be prepared by someone properly qualified for, and attentive to, the erosion/sedimentation issue. We will be pleased to work with the designer in that regard. The existing native and fill soils will be very difficult to filter or precipitate once suspended in surface runoff. Therefore, it will be important to cover and avoid vehicle traffic on exposed soil, especially during wet weather. Coarse sand, straw mulch, hog fuel, nonwoven geotextile or visqueen sheets can be used for cover, depending on the specific conditions. The runoff must be routed through some combination of filters and sedimentation ponds to clarify the water. Water treatment with a flocculent can also be effective. Dust control will be necessary during dry weather. Proper traffic surfaces such as ATB (asphalt-treated base) will help significantly. Water on unpaved surfaces may be adequate. STRUCTURAL FILL Gradation Requirements All new fill placed in shallow foundations, pavement or other settlement-sensitive areas must be placed as compacted structural fill. Criteria for structural fill are described below. All structural fill material should be free of debris, organic contaminants and rock fragments larger than 6 inches. The suitability of material for use as structural fill will depend on the gradation and moisture content of the soil. As the amount of fines (material passing the No. 200 sieve) G e o E n g i n e e r s 10 File No. 0120-214-06-1130/010797 increases, soil becomes increasingly more sensitive to small changes in moisture content and adequate compaction becomes more difficult to achieve. We recommend that structural fill contain no more than about 5 percent fines in the portion passing a 3/4-inch sieve for placement in wet weather or on a wet subgrade. The percent fines can be slightly higher for placement in dry weather, providing that the fill material is moisture-conditioned as necessary for proper compaction. Imported fill can consist of pit run sand or a gravel sand mixture. There are numerous commercial sources of this type of fill in the vicinity of the project. We strongly recommend that the fill source(s) proposed for use by all contractors be evaluated by GeoEngineers prior to import to the project. Fill placed in building areas where the building frame and floor will be supported on piles does not need to be structural, provided it is sufficient to support construction equipment. This fill, however, should be free of debris, organics, and rock fragments larger than 6 inches. Use of On-site Soils The near-surface fill and native soils at the site consist primarily of a silt/sand mixture. Crushed rock and sand and gravel will likely be present along Oaksdale Avenue Southwest and Jackson Avenue Southwest. Based on our test pit explorations, the crushed rock and sand and gravel fill may contain a significant amount of fines. The surficial silty sand fill and existing coarser granular fill may be suitable for use as structural fill provided moisture content at the time of placement is suitable to achieve compaction requirements. If this material is too wet of optimum, it will be necessary to dry the soil prior to placement. The silt-rich fill will only be useful for structural fill during extended dry weather. This material may be suitable for use as nonstructural fill in pile supported building areas or in landscaped areas. Existing crushed rock and sand and gravel fill may be salvaged and stockpiled for later use as structural fill. If these soils are silty or become contaminated with silty soil, they may become difficult to compact and unsuitable for use as structural fill. We anticipate that the native silt encountered below about 2 feet below existing ground surface will not be suitable for use as structural fill under any but the most favorable conditions. This includes soils that may be excavated from dewatered excavations. We understand that time constraints may preclude efficient use of the native material. We therefore recommend that the native silt be used in landscaped areas or wasted off-site. Portions of the drier upper 2 feet of the native silt may be useful to raise grades in the pile supported structural floor slab areas. However, it is our opinion that much of this silt may be too moist and soft even for use in these areas. Compaction Requirements All structural fill placement within 2 feet of the bottom elevation of nonstructural floor slabs, shallow footings, sidewalks, utilities or pavements should be compacted to a minimum of G e o E n g i n e e r s I File No. 0 1 20-214-06-1 1 30/010797 95 percent of the maximum dry density as determined by ASTM D-1557. Below this level, structural fill should be compacted to at least 90 percent of the same standard. No compaction specifications are needed for nonstructural fill placed in areas where structures will be pile- supported. Some limited compaction, however, will likely be needed to provide adequate support of construction equipment. We recommend that structural fill be placed in lifts of not more than 10 inches loose thickness for relatively clean sand and gravel (less than 5 percent silt) and 8 inches for soils containing a higher percentage of silt. Each lift must be conditioned to the proper moisture content for compaction and uniformly compacted to the specified degree before placing subsequent layers. In areas where the subgrade is particularly soft, it may be desirable to place a geotextile fabric between the new fill and the on-site soils to separate these materials. We recommend that a nonwoven fabric such as Mirafi 160N or Phillips Fabrics 4NP be used for this purpose in utility and sidewalk areas. In pavement areas, we recommend a more durable fabric such as Mirafi 500X. Other types and manufacturers of filter fabric may be suitable. The selected fabric should be evaluated by the geotechnical engineer prior to its use. \ We recommend that a representative from GeoEngineers, Inc. be present during site preparation and structural fill placement. Our representative would observe the work, evaluate subgrade performance under proofrolling/probing, perform representative in-place density tests to determine if the required compaction is being achieved and advise on any modifications to procedures or materials which may be appropriate for the prevailing conditions. Fill Settlement We anticipate that areas where more than about 1 foot of new fill is placed will experience settlement as a result of consolidation of the underlying silts and organic silts. We estimate that settlement on the order of 1 to 2 inches per 1 foot of fill thickness may occur. Most of this settlement will typically occur within a period of about one to two months after fill placement. The effect of ground settlement around foundation piling is that piling installed prior to completion of the consolidation process will be subjected to downdrag forces. Downdrag forces will reduce the allowable vertical capacity of piles. The effect of downdrag forces is addressed in our recommendations presented in a subsequent section entitled "FOUNDATION SUPPORT- BCAG BUILDING." We recommend that the structural engineer consider the effect of ground settlement in their design of structures supported on-grade. Where these structures are constructed prior to completion of ground settlement due to raising of site grades, post construction settlement should be expected. We recommend that on-grade components not be structurally connected to pile- supported components to reduce effects of differential settlement between the two. G e o E n g i n e e r s 12 File No.0120-214-06-1130/010797 FOUNDATION SUPPORT - BCAG BUILDING General It is our opinion that building columns and structural floor slabs can adequately be supported on augercast piling. Small, lightly loaded structures such as exterior walkways which are not settlement-sensitive could be supported on conventional shallow footings. Recommendations for shallow foundations are presented in a subsequent section of this report. Site-specific pile design recommendations for augercast piling are presented in this section. The recommendations presented below incorporate the pile load test information obtained during the CSTC development. Previous Pile Load Tests GeoEngineers completed pile load tests on 14-inch-diameter augercast piles and 14-inch- diameter driven grout piles as part of the CSTC development. The results of the pile load tests are presented in our report dated November 6, 1992. A brief summary of the test program and results for the augercast piles is presented below. The pile load test program was designed to obtain information regarding the behavior of augercast piles under compression, tension (uplift), and lateral loading. Two 14-inch-diameter augercast piles were installed to depths of 53 feet and 60 feet, respectively. The piles were instrumented with strain gauges and a telltale to provide information regarding the distribution of load transfer along and at the tip of the piles. The compression and tension tests were completed suing a modified "Quick Test" procedure. During the compressive test, the piles were loaded in 20 ton increments up to a maximum load of 260 tons. During the tension test, the piles were loaded in 10 ton increments up to a maximum load of 80 tons. During the lateral load test, the piles were subjected to lateral loads in 2 ton increments and each load was cycled 10 to 20 times. The results of the augercast pile compressive load tests indicated that the capacity of the piles at a deflection of 1/2 inch was 180 tons for the 53-foot pile and 210 tons for the 60-foot pile. The results of the tension tests indicated an uplift capacity of 50 tons and 75 tons at 1/2- inch deflection for the 53-foot and 60-foot piles, respectively. The results of the lateral load tests indicated that the lateral load was 12 tons at a deflection of 1/2 inch (note: the test piles were installed in a location that contained about 5 feet of compacted race track fill). Axial Pile Capacity Axial pile capacity in compression will be developed primarily from friction and end bearing in the medium dense to very dense sand encountered below 24 to 30 feet in depth. The near-surface soft silt layer has relatively low shear strength and has been ignored in our capacity evaluations. Also, the loose, wet sand which underlies the surficial silt may liquefy and lose strength during an earthquake and was therefore also ignored in our calculations. Uplift pile capacity will be developed primarily from friction in the medium dense to very dense sand layer. G e o E n g i n e e r s 13 File No.0120-214-06-1130/010797 Our recommendations for allowable pile capacities in compression and tension for 14-, 18- and 24-inch-diameter augercast piles are presented in Figure 6. - The values in Figure 6 are for the total of dead and long-term live loads and may be increased by one-third when considering live loads of short duration such as wind or seismic forces. The allowable capacities presented in Figure 6 are based on the strength of the supporting soils for the penetrations indicated and include a factor of safety of at least 2. The capacities apply to single piles. If piles within groups are spaced at least three pile diameters on center, as recommended, no reduction for pile group action is needed. The structural characteristics of pile materials and structural connections may impose limitations on pile capacities and should be evaluated by your structural engineer. For example, steel reinforcing will be needed for augercast piles subjected to uplift. We recommend that a single reinforcing bar be installed the entire length of the augercast pile to develop the allowable uplift capacities presented in Figure 6. There is some risk associated with supporting structural elements on single piles. Therefore, we recommend that all major structural elements be supported on pile groups consisting of two or more piles. Pile Downdrag We anticipate that piling will be installed very soon after building site fill is placed. As previously discussed, downdrag forces that result from compression of the underlying silt and organic silt will reduce the allowable pile capacity in compression. There is no reduction in allowable capacity for piles in tension or for laterally loaded piles due to downdrag forces. We recommend that the allowable capacities presented in Figure 6 be reduced as shown in Table 1 where more than 1 foot of new fill is placed: Table 1 - Reduction of Pile Capacity Due to Downdrag Reduction in Allowable Capacity Pile Diameter in Compression (in.) (tons) 14 11 18 14 24 18 These reductions need not be applied if the piling are installed after the consolidation of the underlying silt and organic silt is completed or nearly completed. We estimate that consolidation will take one to two months to be essentially complete. If reductions in pile capacity due to downdrag are not included in the pile design, we recommend that settlement plates be installed and surveyed twice weekly to evaluate when consolidation is sufficiently completed. G e o E n g i n e e r s 14 File No. 0120-214-06-1130/010797 GeoEngineers should be retained to present more detailed recommendations for settlement plate construction and installation, as well as to evaluate survey data should this course of action be selected. Lateral Capacity General. Lateral foundation loads from earthquakes or wind loads can be resisted by the lateral capacity of vertical piles and by the passive soil pressures in pile caps and structurally connected grade beams. Because of potential separation between the pile-supported foundation components and the underlying soil, base friction on pile caps and grade beam has not been included in our calculations for lateral capacity. It is important that the estimated displacement associated with the pile caps and grade beams be compatible with the estimated displacement to develop the lateral capacity of the piles. Our recommendations for lateral resistance of pile caps and grade beams are presented in Figures 7 and 8. The values presented in Figure 7 assume that the backfill around the pile caps or grade beams is loose sand or soft to medium stiff native silt. If structural fill is placed around these below grade elements, the lateral resistance values presented in Figure 8 should be used. The values presented include a factor of safety of at least 1.3. We present allowable lateral capacities for 14-inch, 18-inch and 24-inch-diameter augercast piles versus deflection at the top of the pile in Figure 9. Estimated maximum allowable moments versus pile depth for fixed-headed conditions are presented in Figures 10 through 12. The values presented include a factor of safety of at least 1.3 and reductions due to pile grouping. The values are based on a minimum pile spacing of three pile diameters. The structural engineer should verify that the piles are structurally designed to resist design lateral loads. Recommended Design Procedure. As stated previously, it is important that the design of the pile caps and piles be compatible with respect to estimated deflections. If the pile cap is designed for 1/2-inch lateral deflection and the connecting piles are designed for 1/4-inch, then the piles will be overstressed. In order to reduce the incompatibility and develop a cost-effective design, we recommend using the iterative procedure presented below. It is assumed in this procedure that the pile caps and grade beams in a particular system are structurally connected so that all pile caps and grade beams deflect laterally approximately the same amount. It is also assumed that the augercast piles are fixed at the pile cap. A lateral deflection of 1/2 inch is used for illustration in the procedure below. The actual design lateral deflection should be used if it i is different than 1/2 inch. 1. Assume a lateral deflection of 1/2 inch for the pile cap/grade beam system. 2. From Figures 7 or 8, depending on the backfill type placed around the pile cap or grade beam, select the appropriate lateral resistance values for the particular pile cap and grade beam thicknesses. Multiply these values by the respective pile cap or grade beam lengths (perpendicular to the direction of loading) and sum the results for each pile cap and grade G e o E n g i nee r s 15 File No.01 20-2 14-06-1 130/0 1 0797 beam in the system to obtain the total lateral resistance of the pile cap/grade beam system for 1/2-inch deflection. Linear interpolation of curves in Figures 7 and 8 can be used. 3. Subtract the total lateral resistance of the pile cap/grade beam system from the total lateral load for the system to obtain the net lateral load that will be transferred to the piles for 1/2-inch deflection of the pile caps and grade beams. 4. Divide the net lateral load transferred to the piles by the total number of piles in the system to obtain the net lateral load transferred to each pile. 5. From Figure 9, depending on the pile diameter, obtain the estimated pile deflection at the top of the pile (i.e., bottom of pile cap) that will result from the net lateral load transferred to the pile calculated from step 4. 6. If the estimated pile deflection at the top of the pile is within an acceptable amount of 1/2 inch (e.g., plus or minus about 1/8 inch) then there is compatibility between the pile cap and piles. Proceed to Step 9. Required compatibility between calculated deflections should be evaluated by the structural engineer. A compatibility of less than 1/8 inch may be appropriate. A 1/8-inch compatibility is used herein for illustration. 7. If the estimated pile deflection calculated in Step 5 is significantly greater than 1/2 inch (e.g., deflection more than about 5/8-inch) then more piles are needed to adequately resist the design lateral loads with less than 1/2 inch of deflection for the system. Add more piles to the system and go back to step 4. Alternatively, a thicker (deeper) pile cap or grade beam can be used to increase passive resistance and reduce deflection. If this alternative method is selected, go back to step 2. 8. If the estimated pile deflection calculated in Step 5 is significantly less than 1/2 inch (e.g., deflection less than about 3/8 inch) then more load needs to be transferred from the pile cap/grade beam system to the piles to make the entire foundation system compatible with respect to deflection. Go back to Step 2 and select another (lower) lateral resistance value for the pile caps and grade beams using the 1/4-inch deflection curve in Figure 7 or 8. Repeat Steps 3 through 5. If the estimated lateral deflection of the top of the pile is within an acceptable amount of 1/4 inch then compatibility is achieved. Proceed to Step 9. If not, then repeat Steps 2 through 5 until the estimated deflection at the top of the pile is within an acceptable amount of the estimated deflection of the pile cap/grade beam system. 9. From Figures 10 through 12, select the appropriate moment curve for the resultant displacement of the foundation system calculated in Steps 6 or 8. Linear interpolation between curves in Figures 10 through 12 is appropriate. The values in Figures 10 through 12 include an implicit factor of safety of 1.3 in that these moments are determined from allowable lateral loads in Figure 9 which do include a factor of safety of 1.3. In our opinion, additional factors of safety are not necessary for seismic design of the foundations. The lateral resistance curves in Figures 7 and 8 assume that the ground water table is below the bottom of the pile cap. Except during design flood levels we anticipate that this will generally be true. We do not feel it is appropriate to design the foundations using design flood levels under G e o E n g i n e e r s 16 File No. 0120-214-06-1130/010797 seismic conditions. A design flood level will occur rarely and the probability of it happening during a design earthquake is remote, in our opinion. Pile Settlement We estimate that the postconstruction settlement of pile foundations, designed and installed as recommended, will be on the order of 1/2 inch or less. Most of this settlement will occur rapidly as loads are applied. Postconstruction differential settlements should be minor. Pile Installation Augercast concrete piles should be installed to the recommended penetrations using a continuous-flight, hollow-stem auger. As is common practice, the pile grout is pumped under pressure through the hollow stem as the auger is withdrawn. Reinforcing steel for bending and uplift is placed in the fresh grout column immediately after withdrawal of the auger. We recommend that the augercast piles be installed by a contractor experienced in their placement and using suitable equipment. Grout pumps must be fitted with a volume-measuring device and pressure gauge so that the volume of grout placed in each pile and the pressure head can be easily determined. While grouting, the rate of auger withdrawal must be controlled such that the volume of grout pumped must be equivalent to at least 115 percent of the theoretical hole volume. A minimum grout line pressure of 100 psi must be maintained while grouting. Also, a minimum head of grout of 8 feet should be maintained at all times while removing the auger. We recommend that a minimum 3,500 psi grout strength be used for augercast piles. We recommend that there be a waiting period of at least eight hours between installation of piles spaced closer than about 8 feet center-to-center, in order to avoid disturbance of concrete undergoing curing in a previously cast pile. It should be noted that the recommended pile penetrations and allowable capacities presented above are based on assumed uniformity of soil conditions between the explorations. There may be unexpected variations in the depth to and characteristics of the supporting soils across the site. In addition, no direct information regarding the capacity of augercast piles (e.g., driving resistance data) is obtained while this type of pile is being installed. Therefore, it is particularly important that the installation be completed under the direct observation of a properly experienced registered engineer. Accordingly, we recommend that pile installation be monitored by a member of our staff who will observe installation procedures and evaluate the adequacy of individual pile installations. FLOOR SLAB SUPPORT The floor slab of the building will be supported on pile foundations. As previously discussed under "SITE PREPARATION AND EARTHWORK," we anticipate that the contractor will place a sufficient quantity of fill in the building area so that the slab can be poured on soil. The fill does not need to be structural provided it is sufficient to support construction equipment. G e o E n g i n e e r s 17 File No.0120-214-06-1130/010797 If the floor slab will have moisture-sensitive coverings (e.g. the or carpeting glued to the slab), we also recommend that a vapor barrier consisting of plastic sheeting be included. A 2-inch covering of clean sand could be used to protect the sheeting and to provide more uniform concrete curing. FOUNDATION SUPPORT - LIGHTLY LOADED STRUCTURES We understand that isolated, lightly loaded structures, such as stairs and walkways, are planned. These types of structures can be supported on conventional spread footings bearing on a minimum of 2 feet of compacted structural fill, placed and compacted as described in a previous section. Exterior footings should be founded at least 18 inches below the lowest adjacent finished grade; interior footings should have a minimum embedment of 12 inches. Individual spread footings should have a minimum width of 2 feet. Continuous strip footings should be at least 18 inches wide. Isolated and continuous footings dimensioned as recommended above and underlain by at least 2 feet of compacted structural fill can be designed for an allowable soil bearing pressure of 2,500 psf. An allowable soil bearing value of 1,500 psf can be used for structures supported on 1 foot of compacted structural fill. We do not recommend supporting shallow foundations directly on native soils. These bearing pressures apply to the sum of all dead plus long-term live loads, excluding the weight of the footing and any overlying backfill. These values may be increased by one-third when earthquake or wind loads are considered. Some limited settlement may occur beneath structures supported on footings. We anticipate that settlement due to dead plus long-term loads will not exceed about 1/2 to 1 inch. These settlements are expected to occur within two to four weeks after the loads are applied. As discussed in the section entitled "SEISMIC CONSIDERATIONS," some additional settlement may occur during an earthquake, resulting from liquefaction of underlying soil. We recommend that, where practical, structures not be supported by combined piles and shallow footings to limit the potential differential settlement between the two support systems. Where structures are supported by a combination of footings and piles, we recommend that a hinge be provided to allow for differential settlements on the order of 1/2 to 1 inch. BURIED STRUCTURES General We understand that several types of buried structures, including the concrete utilidor, vaults and utilities, are planned. Site specific design recommendations for the utilidor and other buried structures are presented below. Our recommendations incorporate our experience and the information obtained during the CSTC development. G e o E n g i n e e r s 18 File No.0120-214-06-1130/010797 Previous Utilidor Construction GeoEngineers observed and provided recommendations during construction of the utilidor for the CSTC development. The excavations for the utilidor were typically 8 to 10 feet below the existing ground surface and were accomplished with temporary cut slopes. The utilidor was supported on 1 foot of structural fill where the existing soils were firm and undisturbed. A leveling course consisting of 6 inches of 5/8-inch crushed rock was placed over the structural fill. In areas where the existing subgrade soils were observed to be soft and wet, the subgrade soils were overexcavated 2 feet and replaced with pit run sand and gravel or quarry spalls overlying a geotextile. The overexcavation zone was then covered with 1 foot of structural fill and 6 inches of leveling course. Two options were successfully utilized where excessively soft and wet subgrade soils were encountered. The first option consisted of overexcavating 2 feet and replacing with quarry spalls overlying a geotextile. Quarry spalls were also used in the structural fill zone. The leveling course was then placed over the 3 foot thickness of quarry spalls. The second option consisted of overexcavating 3 feet and replacing with 1 foot of quarry spalls and 2 feet of pit run sand and gravel overlying a geotextile. The overexcavation zone was then overlain with 1 foot of structural fill and 6 inches of leveling course. The pit run sand and gravel and quarry spalls placed in the overexcavated areas was compacted with a vibratory drum roller. If vibration resulted in pumping or weaving, the lift thickness was reduced and the material was compacted by static rolling. In all of the areas where overexcavation was required for the utilidor, the excavation was completed with cut slopes. This was possible because the material was placed in the overexcavated areas within hours after the excavation was completed. Ground water was also not a problem during the excavation for these sections of the utilidor. Foundation Support Based on our experience during construction of the utilidor for the CSTC development, we recommend that all buried structures, including utilities, bear on a minimum of 12 inches of structural fill placed and compacted in accordance with recommendations presented under "STRUCTURAL FILL." In areas where soft, wet or disturbed subgrade soils are encountered, we recommend that the utilidor and other buried structures be supported in a similar manner to that used during the CSTC development (described above). We expect that the subgrade soil conditions will vary along the utilidor alignment and between the buried structure locations. Therefore, we recommend that the condition of all foundation excavations be observed by a representative from our firm to confirm that subgrade soils are capable of the bearing support and to provide remedial recommendations in areas where soft, wet or disturbed subgrade soils are encountered. G e o E n g i n e e r s 19 File No. 01 20-2 1 4-06-1 130/01 0797 Lateral and Vertical Stresses Lateral earth pressures on walls of buried structures depe x2ll kfill material, ground water levels, compactive effort on backfill and ai _1> g. Additional lateral earth pressure due to seismic loading can also be exaMabmwalls during a sizeable earthquake. Our recommendations for static and seisr&•i �Ssures for rigid walls are presented in Figure 13. We feel it would be prudent to design the walls to resist 1� corresponding to a ground water elevation of +15 feet (corresponding to: ,a te). We have included design hydrostatic pressures in Figure 13. This gro �also be used in the uplift design of the structures. The earth pressure values presented in Figure 13 assume 13&wAlMaining sand and gravel backfill with less than 5 percent fines (that portion fhar4aNkthat passes the No. 200 sieve) within 2 feet of the wall. Recommend atiom 4aI trl placement of structural backfill are presented in a previous section entitled.1017a dFILL." In addition to the lateral stresses, buried structures naelatft resist vertical stresses from overburden and wheel loads. The vertical 1casburden can be calculated using the procedure presented in Figure 13. Addities6asnAing from wheel loads of trucks (rated maximum axle loads of 36 kips) are prtt 'al ° Table 2 - Vertical Stresses on Buried Structures ll'en i ►ads Depth to Top Estimated of Buried Structure Vertical (feet) Stress s 2 1,150 4 350 6 150 8 90 10 70 The recommendations presented in Figure 13 and Table 2 amniMmnal compaction effort is used along the sides and on top of buried structures. k:H; t the contractor take care not to overcompact soils within 3 feet of the sidese top of buried structures. Hand-operated compaction equipment is recommendaA.A khe specifications for maximum loose lift thickness and minimum compaction section entitled "STRUCTURAL FILL" must be followed, G e o E n g i n e e r s 20 SUM-214-06-1130/010797 j I 1 1 Thrust Restraint We recommend that the thrust forces on utilities be resisted using the lateral resistance values for pile caps and grade beams as presented in Figures 7 and 8. The values presented in Figure 7 assume that the backfill around the thrust block is loose sand or soft to medium stiff native silt. If structural fill is placed around the thrust blocks, the lateral resistance values presented in Figure 8 should be used. The values presented include a factor of safety of at least 1.3. Buoyancy Design and Waterproofing Uplift buoyant forces can be resisted using the weight of the wet soil (overburden) above the structure determined from Figure 13 and the total dead weight of the structure itself. With this method of analysis, the total weight of the overlying soil should be used (not the buoyant weight). We do not recommend using friction along the sides of the structure to resist buoyancy due to the possible loss in shear strength should these soils liquefy during an earthquake. For overall uplift stability, H, should not be included in the calculation of the buoyant forces. However, H, should be included for design of the floor slab. We recommend that either Volclay panels, heavy plastic sheeting (at least 30 mil), or both, be installed across the entire wall surface of the utilidor (in addition to clean backfill). Sheeting requires proper seaming and testing to verify tightness. Other types of waterproofing may also be appropriate. EXCAVATIONS General We understand that excavations for building areas will generally be no deeper than about 4 to 5 feet below final grade (1 to 3 feet below existing grade). Excavations for the utilidor and other buried structures will generally be about 8 to 10 feet below the existing ground surface. Based on our understanding of ground water conditions at the site, we expect any excavation that extends below approximately Elevation +10 (about 6 to 9 feet below the existing ground surface) will encounter ground water. Requirements for excavations below the ground water level will be significantly different than for shallow excavations which do not extend into the ground water. In this section, we represent recommendations for both. All steep-sided excavations more than 2 to 3 feet deep will be subject to caving. For excavations more than 4 feet deep, it is critical that standard safety regulations (OSHA or WISHA) be followed. Excavations Above Ground Water Excavations above the ground water table can be made with temporary side slopes of about 11hH:1V (horizontal to vertical). Temporary slopes may need to be flattened where localized zones of extremely loose or soft soils are encountered. In addition, some slope protection such G e o E n g i n e e r s 21 File No. 0120-214-06-1130/010797 as visqueen is recommended for long-term excavations (i.e., those remaining open longer than about one to two weeks or when the excavations are made during periods of high precipitation. Excavations Below Ground Water Significant caving and sloughing of the excavation side walls occurred in our test pits which extended below the ground water. Based on this and our experience during the utilidor construction for the CSTC development, we expect that excavations extending deeper than about 2 to 3 feet below static ground water level will require dewatering, temporary shoring or both. Based on our understanding of the ground water conditions at the site and on the ground water conditions encountered in our test pits, we expect that the majority of the excavations for the utilidor will extend less than 2 to 3 feet below the static ground water level. Ground water in excavations less than 2 to 3 feet below static ground water level can likely be controlled by shallow sumps and small pumps. Open-Cut Excavations with Dewatering Open cuts deeper than about 2 to 3 feet below ground water will generally require dewatering to stabilize the excavation. We recommend that in excavations below the water table, the static ground water level be lowered sufficiently to provide a 2-foot drained zone below the deepest point of the excavation. The excavation should be deep enough to permit a 1-foot-thick layer of structural fill below the structure plus a 2-foot factor of safety to the water table. The soils observed in our explorations are relatively fine-grained and of moderate permeability. Therefore, significant inflow of ground water is not expected. Because of the fine- grained nature of the soil, we expect that the effect of deep wells on ground water levels would not extend far from the well casing. Therefore, we do not recommend deep, larger diameter wells for dewatering at this site. In our opinion, the contractor should be responsible for designing and installing the appropriate dewatering system needed to complete the work. The contractor should be experienced with the soil conditions encountered at the site. Appropriate discharge points should be designated by the contractor. We recommend that the details of the dewatering system be reviewed by GeoEngineers prior to construction. This will allow us to evaluate if the designs are consistent with the intent of our recommendations, and to provide supplemental recommendations in a timely manner. Excavations made below the ground water level should be no steeper than about 2H:1V, even where a dewatering system is used. Flatter cuts may be required where localized sloughing occurs. To reduce instability of open-cut excavations, we recommend that: • No traffic, construction equipment, or building supplies be allowed at the top of cut slopes for a distance of at least one-half the depth of the cut; • Exposed soil along the slope be protected from surface erosion using waterproof tarps or visqueen; G e o E n g i nee r s 22 File No. 0 1 20-2 1 4-06-1 130/01 0797 • Construction time be scheduled so that the length of time the temporary cut is left open is minimized; and • The general conditions of the slopes be observed by a geotechnical engineer periodically to identify potential problems. Other dewatering issues which must be addressed include disposal of water and backup power. We anticipate that water removed from excavations will be diverted either to Metro's storm drain system or to nearby Springbrook Creek. Permits will be required for either discharge point. Water sampling prior to and during dewatering will also be required as part of the permit. Based on recent experience, one to two months should be scheduled for dewatering permits. We recommend that the dewatering contractor be required to supply the backup power supply. This is because a failure of dewatering pumps, even for relatively short periods of time, may result in increased water levels which, in turn, will likely cause significant sloughing and possible failure of the side slopes. We recommend that the contractor be made responsible for the stability of cut slopes, as well as safety in the excavations, since the contractor has control of construction operations. We also recommend that a separate line item be included for dewatering in the construction bid documents. This would allow an evaluation of the proposed dewatering scheme separate from the rest of the bid. Shored Excavations Temporary shoring can be used as an alternate to an open-cut. To reduce water inflow, we recommend that temporary shoring consist of tightly interlocking sheet piles driven sufficiently deep below the base of excavation level. We do not recommend the use of soldier piles with lagging due to the potential for fine-grained soils to flow into the excavation through the lagging. Dewatering will be required even if properly designed and installed shoring is used. If the shoring piles extend deep enough to offset the hydrostatic head difference from outside to inside the excavation, internal pumping using shallow sumps and small pumps may be adequate. If the sheet piles are driven only deep enough to secure the pile tips then an efficient system of dewatering well points will likely be required. It is not within the scope of our services to provide specific recommendations for shoring design. For cantilevered shoring, the static lateral earth pressure recommendations presented in the "BURIED STRUCTURES" section can be used for preliminary design. Earth pressures for braced excavations may be different. We recommend that any shoring used at this site be designed by a licensed structural engineer. GeoEngineers should be retained to provide geotechnical input to final shoring design and to review the design to evaluate whether the recommendations presented have been properly interpreted. G e o E n g i n e e r s 23 File No. 0 1 20-2 1 4-06-1 1 30/0 1 0797 PAVEMENTS This section addresses subgrade preparation and pavement sections. The particular pavements considered include municipal streets, on-site roadways, parking lots, sidewalks and miscellaneous on-grade slabs. Pavement subgrade areas should be stripped, proofrolled and otherwise examined as recommended in a previous report section entitled "SITE PREPARATION AND EARTHWORK." If pavements are constructed during wet weather or if the subgrade is wet and cannot be compacted satisfactorily, we recommend that consideration be given to placing a layer of geotextile such as Mirafi 50OX between the native soils and the granular fill to separate these materials and strengthen the pavement section. This was successfully used at the CSTC development. We recommend that some geotextile be stored at the site to expedite construction. We recommend waiting about three to four weeks after fill placement is completed for final paving to allow expected ground settlement to occurred. We have completed a pavement design analysis for areas to be paved with asphalt. Based on discussions with the City of Renton Traffic Engineering Department, we have assumed a 15- year design life and a design wheel load related to a 36-kip-truck-axle load for the pavement design of Oaksdale Avenue Southwest and Jackson Avenue Southwest. Our recommendations for minimum pavement sections for Oaksdale Avenue Southwest and Jackson Avenue Southwest, drive areas around buildings and automobile parking areas are presented in Table 3. Table 3 - Recommended Asphalt Pavement Sections Recommended Thicknesses (inches) Pavement W.S.D.O.T.* Southwest Drive Automobile Layer Specification 16th Street Areas Parking A, reas Class B Surface 9-03.8(6) 4 3 2 Crushed Rock Base 9-03.9(3) 8 6 4 Structural Fill Subbase 9-03.10 12 12 12 *Washington State Department of Transportation Standard Specifications for Road, Bridge and Municipal Construction, 1994 We recommend that the sand and gravel fill placed in the subbase contain less than 5 percent passing the No. 200 sieve. The subbase material should be placed according to the recommendations for "STRUCTURAL FILL." The crushed rock base course and the granular G e o E n g i n e e r s 24 File No. 0120-214-06-1130/010797 subbase fill should both be compacted to at least 95 percent of the maximum dry density determined in accordance with ASTM D-1557. It is very important to pavement performance that backfill in utility trenches underlying paved areas also be compacted in accordance with the recommendations for structural fill presented in this report. We understand that ATB (asphalt treated base) sections may be used to support construction equipment during construction. At the completion of construction, the ATB would be overlain with asphalt concrete to provide final pavement sections. We recommend that the pavement sections consist of ATB overlying a minimum of 12 inches of structural fill subbase. The required thickness of ATB in the roadway and staging areas during construction will be dependant on the thickness of the subbase material. The thickness of the fill required to raise site grades which we assume will be the same material as that used as the subbase, will generally increase toward the south. Our recommendations for minimum ATB pavement sections are presented in Table 4. Table 4 - Recommended ATB Pavement Sections Pavement W.S.D.O.T.* Layer Specification Recommended Thicknesses (inches) ATB 4-06.2 9 7 5 Structural Fill Subbase & Site Grade Fill 9-03.10 > 12 > 18 >24 *Washington State Department of Transportation Standard Specifications for Road, Bridge and Municipal Construction, 1994 The above recommendations for use of ATB are based on our experience during construction of the Boeing CSTC building. Depending on the frequency of construction traffic on the above pavement sections, it should be expected that some localized areas of the ATB will need to be repaired and/or replaced prior to placing the asphalt concrete. We recommend that a CBR (California Bearing Ratio) value of 2 and a resilient modulus of 3,000 psi (pounds per square inch) be used for a subgrade consisting of native silt for the design of pavements. A modulus of subgrade reaction of 150 pci (pounds per cubic inch) is recommended for concrete slabs supported on at least 1 foot of compacted structural fill over native subgrade materials. G e o E n g i n e e r s 25 File No. 0120-214-06-1130/010797 Subgrade preparation for sidewalks and miscellaneous on-grade slabs will vary with site conditions and intended use. Where these slabs are underlain by imported clean sand and gravel compacted as structural fill, no other preparations are necessary. If native soil or sandy silt fill is present at the subgrade level, we recommend that a minimum of 6 inches of clean sand and gravel base course be installed for drainage and leveling. The native soil or fill subgrade surface must be thoroughly proofrolled and any soft or yielding spots must be adequately compacted or replaced with structural fill. If the sidewalk or slab pavement will be subject to vehicle traffic, the subgrade and pavement section must be treated as a roadway and designed as described above. LIMITATIONS We have prepared this report for use by The Boeing Company, Sverdrup Corporation, and other members of the project design team in the design and planning of a portion of this project. The report is not intended for use by others and the information contained herein is not applicable to other sites. The data and report should be provided to prospective contractors for bidding or estimating purposes, but our report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions. When the design has been finalized, we recommend that GeoEngineers, Inc. be retained to review the final design and specifications to see that our recommendations have been interpreted and implemented as intended. The scope of our services does not include services related to construction safety precautions and our recommendations are not intended to direct the contractor's method, techniques, sequences or procedures, except as specifically described in our report for consideration in design. Variations in subsurface conditions between the explorations and also with time should be expected. A contingency for unanticipated conditions should be included in the budget and schedule. Construction monitoring and testing is important to confirm that the conditions encountered are consistent with those indicated by the explorations and to evaluate whether or not earthwork and foundation installation activities comply with the intent of contract plans and specifications. For consistency in the interpretation of subsurface conditions and the application of design recommendations, GeoEngineers, Inc. should be retained to provide construction monitoring and consultation services during earthwork and pile foundation activities. Within the limitations of scope, schedule and budget, our services have been accomplished in accordance with generally accepted practices in this area at the time the report was prepared. No warranty or other conditions, express or implied, should be understood. G e o E n g i n e e r s 26 File No. 0120-214-06-1130/010797 We appreciate this opportunity to be.of service to you on this project. Should you have any questions concerning this report or if we can be of additional service, please call. Respectfully submitted, GeoEngineers, Inc. 1J A r `Q Shaun D. Stauffer, P.E. Project Engineer �EXPiRES _ )1�.�_...j or: M. Denby, P.E. Principal SDS:GMD:wd Document ID: 0120214TINALSTEP! G e o E n g i n e e r s 27 File No.0120-214-06-1130/010797 =-BM — * t cart 254 18 RpILROAO \ , u _:`'� F Fd zi �-.— L,� F ■'� `� I 1 (� :� L• ;�-r�;. Golf Course �T� � � ' � -i= -� `_� , ••ill // \ -1 I- ' �•-----"- 130 Z,—age uoapi_— 23, 2. rLongacre BGAC DEVELOPMENT•SITE I + 61■ --- ` I• Track I _ ��'t• �• f'3k / 1 I _ 4. ;I, B ME!29• -- ----— --J �!, t� �• )210 2'f4\� I j r • �: r_ / ReservoirANN — W L I,• 1/ to . �,. I � •.. ( L l r ./ 261 � .;: i I 25 .30 Izo3 116 2. I 41 17 q.�,.•...--: 1//111 i 1�I /I I � � �C ��F. \ M. 94� i I 1 '� �. •i.: 0 2000 4000 SCALE IN FEET N 0 0 CONTOUR INTERVAL 25 FEET N I o Reference: USGS 7.5' topographic quadrangle map -Renton, Wash." photorevised 1973. Q �u VICINITY MAP Geo Enolneers FIGURE 1 0 If + ----------- If \+ Z, ­­�......... .......... ............ ....................... .......................... ........... ----­------------ ----- TP—1 --- -TP-9 -41 'TP—17 _X. _2i ll . .......... (*A T (—3 �TP-12 N ITP—1' Uj P T T "PT-3 B-21 4 CPT I�I I III I I I I hl'I I I I FE B-8 MW-32 ILI f. LU .......... z u N F PROPOSED BUILDING _j itA PROPOSED PARKING ................ +,,'f; ,,, I .� �� f..��� ` t C CPT-6 I I I I I Irl /6111 1 11,11, T 2 � L i i ; jTP-7 7 P_ - 11 N L 14 JIM, ............ I .............. iB 20+ •5 .................. CPT— At­ I if J-QJTIj-ITHtk 1- ............ TP-6 TP-16 TP75 44- ....... .......................... ......... ...................... ..........7F7= -------------- .. ....------------- - --------­----- ----------- ---- -- .......... Cl) ......... 0 a . 100 200 + MM===!5MMMMW0Mi "+ SCALE IN FEET EXPLANATION:, Notes: 1. Refer to Figure 1 for Area B location. AL _j XCROSS SECTION LOCATION 2. The locations of all features shown are approximate. C\j B-20 * BORING COMPLETED FOR CURRENT STUDY I 0 CPT-1 CONE PENETRATION TEST PIT COMPLETED FOR CURRENT STUDY Reference: Untitled undated site plan provided by Sverdrup Corporation. 117 0 TP-3 TEST PIT COMPLETED FOR CURRENT STUDY SITE PLAN — AREA B B-5 BORING COMPLETED FOR PREVIOUS STUDY (GEOENGINEERS REPORT DATED 01/23/91) Geo*r%00-Engineers ,a 0 MW-32 MONITORING WELL COMPLETED FOR PREVIOUS STUDY (GEOENGINEERS REPORT DATED 12/09/91) FIGURE 2 „ , MATCHLINE (FIGURE 2) ` / f,}•,I I i'� ..I-. !1S,-I�I �/�� ,.;1�Irt�� 1"� • � -/ j/ ���/ /%/ U.{{'��q�p/��1b••!•� �F,.�• ''�F��-(T_ .L 1-� 2 Q11 C1 j.x '1. 'I-, I.. t� i I� ' I,,�i•' � I - II ;' i PIT ' / � \ . ]S}1 �c, � �oy\/ F /�,3 I•' L .-1- �, � -- �1•..... I I I •'� II II I 1 � 7 Ii I.• • /-yq�t 1.. �\I JI .T '\/ .J / �., •i• I el w �I r: I I 1 I ,I I I:I I . I ,1 1 � I f�• �r ', s ..,,,•a' �,P�...,..•' 1-��.I. �:� .�ii� ...�w ,� ur..�'/� // N„ �,,,.a•"'�II\16'fNSZR E 'i��-�----x _I �•.111. t ,i:. I I _ .__!_._ jl,I 1• i I �•;�s ,1 GPP9y i(.! la� r�. �. .�,: `T�\ _ !'�'.• i rs "'m' �' y :,,,;.:TE - I -�� - - I - �.,�— .�•' � \ � ` �� 5� +�”' •�"�'f71Tn�I-f-F�hl I I f��_..�;' � {; ;`� , II , I, _ ' �,', , _; \ .sue 'j i i. �t i� \\ F� I ��/t N '• 4�� )f �\�'� ./� �• '_,J.�•._...'_\ { li , , tit,' ��C. ``�,•.t:/: % ' /t/ � !. ti��\��• ;�,��. /::'.� •J,. :%�S •�1'J��..''''.. � �\ ••°) _ - I �I• {I �1 I -•.� I Il; �� I �'�j� i.Y\• .,\t\ :\. J\t l yi /�� �.r.l.. �1 _, �f ^>•• .b.; 'I - - - - +- \ _ '�. rlr f; ia�...,�1 a v'x _.� 1, = _ _ = - _ _-, _,_ -` = _•., = II +� �� TP-18 .,..'<i/S .I •1�'.•.j L,r"( ��^_fL..ai �..� j i ,/ ��� - _ - _ - _ - - _ - __�� •I•ti. Il 1, r 1 LJ/ .?- �`��^'8 / 1r'' _) 1="' �/_j I ; +•!�' J—`' _ - - _ - - - -I - -n N I�li--J `\...%`� - _ • ' 7I� i I J1.r \ �' 1 .•-.y ., t: , ! / �' ,'. _ _ (...._. .` ...t.. 0 150 300 ...........5. _ ' �i A � ,... ! ,• I .,l i � 1, � .. '-:r .M-- ? UU � i I UIII l l U iY�11L ��I �};lµl l �t li i \ - . , I p I' �nl�l�i �il� •I. I a r I — -� —— I it \li \ �•"'. �! /Ti ._,.. .,t:1'I �, I I. .. 1 - ��� 'j :I I 1i11- -- X �[TP-21 \ SCALE IN FEET �-. chi I �` L- . I� \I I. PROPOSED ROAD Nji 11, TP-19 y a. •� �.'.. I I .I i I . ��s� 11 ':,,tit' '. •'i 1 r t i�- r i — � - - -- I / 'i�' Ir... , - -- ,,,.:,y ,r, �,u .yA;z� n'�.•Prr-rtlt 1 Ou 4 il. I rrl, ..: �/'. �t1/f. .. 'Z II I _ AREA A _- TP-20 I '•, ,. ,/�of 1 `.��.I,.i= ( �� 1 IJt :.,- . EXPLANATION: O TP-18 TEST PIT COMPLETED FOR CURRENT STUDY O - ' I— .. ti�__�_�•_---..... yam'..-_.1 �� i .. v-- _ AREA C N O o Notes: 1. Refer to Figure 1 for Area A and C locations. g 2. The locations of all features shown are approximate. Geo��1�. SITE PLAN — AREAS A AND C l EI1g veers - o Reference: Untitled, undated site plan provided by Sverdrup Corporation. 14P FIGURE 3 N BGAC Building A O r X N Loose silty sand H Existing Ground Surface N 20 m (fill)(SM) U m 20 6 -2 Very soft to soft silt (ML) g 4 0 6 ? 0 Loose to medium dense sand 13 29 to silty sand (SP to SM) 16 7 27 _ 18 ? 35 Soft to medium stiff 29 -20 19 organic silt (OL) 19 -20 u_ 2 c � 31 6 - � c 0 2g 29 0 M , 14 39 Q) w -40 35 39 27 A 38 23 35 40 Medium dense to very dense sand with 50 -60 52 varying amounts of gravel (SP to SW) 50/5' -60 49 22 15 50/5' 30 -80 -80 EXPLANATION: O o N BORING �_ pp o HORIZONTAL SCALE: 1'=40' Y VERTICAL SCALE: 1"=20' VERTICAL EXAGGERATION: 2X 6 BLOW COUNT (REFER Cn Cn TO FIGURE A-2 N o Notes: 1 . Subsurface conditions shown are based on interpolation between widely space explorations N o and should be considered approximate; actual subsurface conditions may vary from those shown. 2. Refer to Figure 2 for location Section A — A'. � CROSS SECTION A—A' its 3. Elevations shown are based on topographic information on site plan provided by Sverdrup Corporation. �'(`eo��Engineers FIGURE 4 BGAC Building Bb B M Roadway Existing Ground Surface W 20 U CIO U) m 00 U Gravel Path Pond "N" CIO O 20 8 2 Very soft to medium 4 ' ? 1 stiff silt (ML) 6 �----- ? ? 2 8 4 ? 0 Loose to medium dense sand 4 0 11 Soft to medium stiff 13 to silty sand (SP to SM) 11 8 organic silt (OL) 18 _. ? ? 31 �? 1 ? ? 18 29 —20 9 -------- _ 29 40 —20 ii 35 19 21 ILL •c 26 .c 35 0 25 29 23 M 23 co > a) 42 39 50 —40 w w —40 32 39 45 38 35 Medium dense to very dense sand with varying amounts of gravel (SP to SW) -50 —60 —60 50/5' -22 50/5" —80 —80 EXPLANATION: T �j BORING N m O o HORIZONTAL SCALE: 1"=40' VERTICAL SCALE: 1"=20' Y VERTICAL EXAGGERATION: 2X 6 BLOW COUNT (REFER Y cis TO FIGURE A-2 0 T N Notes: 1. Subsurface conditions shown are based on interpolation between widely space explorations o and should be considered approximate; actual subsurface conditions may vary from those shown. N 2. Refer to Figure 2 for location Section B — B'. �� CROSS SECTION B—B' Geo�p Engineers 3. Elevations shown are based on topographic information on site plan provided by Sverdrup Corporation., \/ FIGURE 5 240 EXPLANATION 200 COMPRESSION UPLIFT r 160 H U c4 C. c� 120 U •a X Q 80 0 2 Minimum Embedment = 40 Feet 40 0 0 0 10 20 30 40 50- 60 70 ~ Depth Below Existing Ground Surface (Feet) Y Y _v +5 -5 -15 -25 -35 -45 -55 N o Pile Tip Elevation (Feet) _N O NOTE: THE ALLOWABLE PILE CAPACITIES PRESENTED ABOVE DO NOT INCLUDE THE EFFECTS OF DOWNDRAG. THE FOLLOWING DOWNDRAG FORCE IS RECOMMENDED, AS APPROPRIATE: 14'o - 11 TONS 18'o - 14 TONS 24'o - 18 TONS _ /��� ALLOWABLE AXIAL PILE CAPACITIES \� . FOR AUGERCAST PILING Ue0 �Engineers FIGURE 6 4.0 Assumptions 1. Backfill around pile caps or grade beams is loose sand. 6' > Thickness 3.5 2. Ground water is below of Pile Cap or bottom of pile cap or Grade Beam grade beam. 0 3. Concrete surfaces have O some roughness. IL N 3.0 c 4. The factor of safety is 1.3. a� m 2.5 cz 0 o a U � 2.0 i d m c 0 Q m U c 1.5 cc a� u 1.0 J rn N O r 0 Y 0.5 Y W 0 N I O _ N 0 0 0 0.1 0.2 0.3 0. 04 5 0.6 0.7 0.8 91 0 Lateral Deflection of Pile Cap or Grade Beam (Inches) LATERAL RESISTANCE ALONG PILE CAP LOOSE SAND BACKFILL Geo sZp Engineers FIGURE 7 8.0 Assumptions: 1. Backfill around pile caps or 6` > Thickness grade beams is compacted of Pile Cap or sand or gravel. Grade Beam 7.0 2. Ground water is below bottom of pile cap or grade beam. 3. Concrete surfaces have LL some roughness. 6.0 5� 4. The factor of safety is 1.3. a) M a� m 5.0 C3 0 0 a cc U 4.0 4' a c 0 Q a� C 3.0 cc m Cr a, 3' a 2.0 J rn N O T O Y 1.0 2, U) v N I cli O 0 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 Lateral Deflection of Pile Cap or Grade Beam (Inches) LATERAL RESISTANCE ALONG PILE CAP \�/ COMPACTED GRANULAR BACKFILL Geo �Engineers FIGURE 8 14 F.S.=1.3 (Also includes reduction for effect of group action on soil resistance) 12 P � r y �11 II 24"o N 10 c aJ 2 U C4 8 a M U N 18110 a Cz 6 J _U 3 14110 0 Q 4 r` rn N 0 0 F- 2 Y Y W r) W T N 0 0 r 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 0 Calculated Lateral Deflection at Top of Pile (y)(Inches) Ito. LATERAL PILE CAPACITY VS. DEFLECTION Engineers Geo FIGURE 9 Calculated Moment in Pile (Kip-Feet) 0 -80 -60 -40 -20 0 +20 3/4" 1/2" 1/4" 2 y=1" 4 6 8 14"o Augercast Pile 10 F.S.=1.3 m u_ a cc 12 U a� a 14 0 PL -I 1 i v E 16 m 3 0 18 a5 m r 20 22 24 rn 0 26 0 Y 28 Y W Q U T N i O _N O _ PILE MOMENT VS. DEPTH ts ' 24—INCH DIAMETER AUGERCAST PILE Geo1`*QAZ-1p0Engineers FIGURE 10 Calculated Moment in Pile (Kip-Feet) -160 -140 -120 -100 -80 -60 -40 -20 0 20 40 60 0 3/4" 1/2" 1/4" Y=111 4 8 18"o Augercast Pile l D a 12 F.S.=1.3 c� U a P� �{ i v 0 E 16 0 0 m 3 0 W m 20 L r.. a a) 0 24 rn N O O f— Y vi 28 C W N I O _N 32 _ �i�s. PILE MOMENT VS. DEPTH Geo 1!Engineers 18-INCH DIAMETER AUGERCAST PILE FIGURE 11 Calculated Moment in Pile (Kip-Feet) -180 -160 -140 -120 -100 -80 -60 -40 -20 0 20 40 60 80 0 3/4" 1/2" 1/4" 4- Y=JIF 8 M=240 Kip-Feet 9 y=3/4" 12 M=290 Kip-Feet C y=1" U CL 16 U ry a 20 24"m Augercast Pile 0 F.S.=1.3 E 0 24 0 PLj 75 28 n] 32 36 40 44 rn N O O F- Y Y 0 (n T N I O _N O PILE MOMENT VS. DEPTH 24—INCH DIAMETER AUGERCAST PILE Geo\o Engineers FIGURE 12 Recommended Design Ground Water Elevation = + 15 Feet Final Grade _ H, Weight of Overburden H, 2 1 r 25(Hr) 62.4(H,+Hz) G � v p :'o 0 -v. Q � I Total Dead Weight c of Structure + + 1. v• v . Q v.. I �. e 1 Foot (Min-) °!0� 0o4�0:Q°:a.�.. ooano: O:•.:'.o:uv �. o�.�o-�.QO o:Qpa9 0•:�.�QpQ000°�o- 25(N+H,) 62.4(H,+K+HQ 10(H,) C ... N Structural RII Buried Concrete Structure o At-Rest Hydrostatic Seismic T O I- Y Bouyant Forces=62AH1+ H2+ H3) Cn - - - 12 CO v Notes: 1. Earth pressures are given in terms of ultimate equivalent fluid pressure. N We recommend that a safety factor of 1 .5 or greater be used with these values. I 0 N 0 2. The total weight of overburden that must be resisted by the top of the buried structure can be estimated by multiplying the total volume of soil (determined from the above geometry) by 145 pcf (wet unit weight of the soil . 3. For overall uplift stability, H, should not be included in the calculation of the bouyant forces. H, should be included for design of the floor slab. �p� RUOVERBURDEN AND LATERAL EARTH PRESSURES \�/ ON BURIED STCTURES Geo� Engineers FIGURE 13 APPENDIX A APPENDIX A FIELD EXPLORATIONS Subsurface soil and ground water conditions at the site were explored by drilling two borings (B-20 and B-21) to depths ranging from 89 to 94 feet, performing seven CPT (cone penetration test) probes (CPT-1 through CPT-7) to depths ranging from about 65 to 75 feet, and excavating twenty test pits (TP-3 through TP-22) to depths ranging from about 8 to 15 feet. The borings were drilled by Holt Drilling on December 9 and 10, 1996 using truck-mounted, hollow stem auger drilling equipment. The CPT probes were performed by Northwest Cone Exploration on December 9 and 11, 1996 using truck-mounted electrical cone equipment. The test pits were excavated by Custom Backhoe on December 11 and 12, 1996 using a rubber-tired backhoe. Locations of the explorations were determined in the field by measuring distances from existing site features. The locations of the explorations are shown on the Site Plan, Figures 2 and 3. The borings and test pits were continuously monitored by an engineering geologist from our firm who examined and classified the soils encountered, obtained representative soil samples, observed ground water conditions, and prepared a detailed log of each exploration. Representative soil samples were obtained from the boring at selected depths using a 2.4-inch- inside-diameter split-barrel sampler driven into the soil with a 300-pound hammer free-falling a vertical distance of about 30 inches. The number of blows required to drive the sampler the last 12 inches, or other indicated distance, is recorded on the boring log. Grab samples were obtained from the various soil layers encountered in the test pits. Soils encountered in the explorations were visually classified in general accordance with the classification system described in Figure A-1. A key to the boring log symbols is provided in Figure A-2. The logs of the borings, CPT probes, and test pits are presented in Figures A-3 through A-21. The logs are based on our interpretation of the field and laboratory data and indicate the various types of soils encountered. They also indicate the depths at which the subsurface materials change, although the change might actually be gradual. The densities noted on the boring logs are based on the blow count data obtained in the borings. The densities noted on the CPT probe logs are based on the penetration resistance during pushing of the probe. The densities noted on the test pit logs are based on the difficulty of digging, probing with a 1/2-inch- diameter hand probe, and our experience and judgment. G e o E n g i nee r s A - 1 File No.0 1 20-2 14-06-1 1 30/0 1 0797 SOIL CLASSIFICATION SYSTEM GROUP MAJOR DIVISIONS SYMBOL GROUP NAME GRAVEL CLEAN GW WELL-GRADED GRAVEL, FINE TO COARSE GRAVEL COARSE GRAVEL GRAINED GP POORLY-GRADED GRAVEL SOILS More Than 50% of Coarse Fraction GRAVEL GM SILTY GRAVEL Retained WITH FINES on No. 4 Sieve GC CLAYEY GRAVEL More Than 50% SAND CLEAN SAND SW WELL-GRADED SAND, FINE TO COARSE SAND Retained on No. 200 Sieve SP POORLY-GRADED SAND More Than 50% of Coarse Fraction SAND SM SILTY SAND Passes WITH FINES No. 4 Sieve SC CLAYEY SAND FINE SILT AND CLAY ML SILT GRAINED INORGANIC SOILS CL CLAY Liquid Limit Less Than 50 ORGANIC OL ORGANIC SILT, ORGANIC CLAY More Than 50% SILT AND CLAY MH SILT OF HIGH PLASTICITY, ELASTIC SILT INORGANIC Passes CH CLAY OF HIGH PLASTICITY, FAT CLAY No. 200 Sieve Liquid Limit 50 or More ORGANIC OH ORGANIC CLAY,ORGANIC SILT HIGHLY ORGANIC SOILS PT PEAT NOTES: SOIL MOISTURE MODIFIERS: 1. Field classification is based on visual examination of soil Dry- Absence of moisture, dusty, dry to the touch in general accordance with ASTM D2488-90. Moist- Damp, but no visible water 2. Soil classification using laboratory tests is based on ASTM D2487-90. Wet- Visible free water or saturated, usually soil is obtained from below water table 3. Descriptions of soil density or consistency are based on interpretation of blow count data, visual appearance of soils, and/or test data. M O N ��� SOIL CLASSIFICATION SYSTEM w Geo�aoEngineers FIGURE A-1 FLABORATORY TESTS: SOIL GRAPH: Atterberg limits Compaction SM Soil Group Symbol Consolidation (See Note 2) DS Direct shear GS Grain - size Distinct Contact Between %F Percent fines Soil Strata HA Hydrometer analysis Gradual or Approximate SK Permeability Location of Change SM Moisture content Between Soil Strata MD Moisture and density SP Swelling pressure Water Level TX Triaxial compression Bottom of Boring UC Unconfined compression CA Chemical analysis BLOW-COUNT/SAMPLE DATA: 22 Location of relatively Blows required to drive a 2.4-inch I.D. undisturbed sample split-barrel sampler 12 inches or other indicated distances using a 12 ® Location of disturbed sample 300-pound hammer falling 30 inches. ---J<17 ❑ Location of sampling attempt with no recovery 10 0 Location of sample obtained Blows required to drive a 1.5-inch I.D. in general accordance with (SPT) split-barrel sampler 12 inches Standard Penetration Test or other indicated distances using (ASTM D-1586) procedures 140-pound hammer falling 30 inches. 26 m Location of SPT sampling attempt with no recovery ® Location of grab sample "P" indicates sampler pushed with weight of hammer or against weight of drill rig. NOTES: 1. The reader must refer to the discussion in the report text, the Key to Boring Log Symbols and the exploration logs for a proper understanding of subsurface conditions. 2. Soil classification system is summarized in Figure A-1. Q KEY TO BORING LOG SYMBOLS Geo\Engineers FIGURE A-2 TEST DATA BORING B-20 DESCRIPTION Moisture Dry Content Density Blow Group Surface Elevation(ft.): 16.7 Lab Tests (%) (pcf) Count Samples Symbol 0 SM Brown silty fine sand with occasional organic matter(loose, 0 moist)(fill) 6 ML Brown and gray fine sandy silt with occasional organic matter (soft, moist) 5 5 Grades to very soft 1 � 10 10 SM Gray silty fine sand(loose,wet) MD, 30 85 9 %F 15 15 H- w u- OL Brown organic silt interbedded with fine sand (soft, wet) Z MD 171 36 6 LU p 20 SP Black fine sand(medium dense, wet) 20 MD 23 122 29 25 ::: 25 OL Brown organic silt interbedded with fine sand(medium stiff, _ m wet) 27 13#SP Black fine sand(medium dense to dense,wet) N :.. 30 30 V) Grades to fine to medium sand with occasional gravel MD 10 124 35 35 35 o p 19 ®:...... N 6 40 40 NrLL Note: See Figure A-2 for explanation of symbols � � LOG OF BORING Geo 4w Engineers FIGURE A-3 TEST DATA BORING B-20 (Continued) DESCRIPTION Moisture Dry Content Density Blow Group Lab Tests (%) (pcf) Count Samples Symbol 40 40 SP Black fine sand with occasional fine gravel and shell fragments (medium dense to dense,wet) 31 ■ ::::::; 45 45 MD 22 107 29 ■ ::::::: 50 50 14 55 ::: 55 SW Gray fine to coarse sand with fine gravel(dense, wet) w w LL Z 35 ■ a p 60 60 ° 0°0 GP Gray fine gravel with fine to coarse sand(medium dense,wet) 0 0 0 0 MD, 8 136 27 ■ 0 0 0 0 GS 0 0 0 0 65 000° 65 0 SW Gray fine to coarse sand with fine gravel(medium dense to dense, wet) m 0 23 N 70 70 U V) MD 9 132 40 ■ 75 75 0 `O 52 ■; Grades to very dense 0 v N 0 80 80 N 0 Note: See Figure A-2 for explanation of symbols � LOG OF BORING Geo\ Engineers E FIGURE A-3 TEST DATA BORING B-20 (Continued) DESCRIPTION Moisture Dry Content Density Blow Group Lab Tests (%) (pcf) Count Samples Symbol 80 80 SP Gray fine sand with occasional fine gravel(dense to very dense, wet) MD 19 106 49 1 85 85 15* 90 90 MD 20 110 30 Boring completed at 94.0 feet on 12/09/96 95 Ground water encountered at 8.0 feet during drilling 95 *Note: Blow count may not be representative due to heave LU W during sampling e_ z CL 0100 100 105 105 rn 0 co N 110 110 U U) 0 115 115 0 0 120 0 120 N 0 Note: See Figure A-2 for explanation of symbols /����• LOG OF BORING Geo�F Engineers FIGURE A-3 TEST DATA BORING B-21 ' DESCRIPTION Moisture Dry Content Density Blow Group Surface Elevation(ft.): 17.0 Lab Tests (%) (pcf) Count Samples Symbol 0 ML Brown and gray fine sandy silt with occasional organic matter 0 (very soft,moist) 2 5 5 MD 42 78 1 ■ SM Black silty fine sand with occasional organic matter(loose, wet) 10 10 MD, 31 91 4 ■ ::::::: %F 15 15 SP Black fine sand(medium dense,wet) w .. w LL Z MD, 34 89 13 ■ GS a 0 20 20 18 25 ::: 25 M MD 27 98 18 ■ ::::::: N OL Brown organic silt interbedded with fine sand(medium stiff, `O 30 wet) 30 SP Black fine sand(medium dense,wet) W N 29 ■ ::: ::: 35 Grades to fine sand with occasional gravel 35 0 o MD 20 115 19 ■ N 6 40 40 0 Note: See Figure A-2 for explanation of symbols LOG OF BORING Geo Engineers FIGURE A-4 TEST DATA BORING B-21 (Continued) DESCRIPTION Moisture Dry Content Density Blow Group Lab Tests M (pco Count Samples Symbol 40 40 26 ■ SP Black fine to medium sand with occasional fine gravel and shell 45 fragments(medium dense to dense, wet) 45 MD 21 107 29 ■ 50 50 39 ■ 55 55 o SW Gray fine to coarse sand with gravel(dense,wet) w u- Z MD 13 128 39 ■ a p 60 60 38 ■ 65 65 m 0 35 ■ N 70 N 70 U W 1 MD 9 128 50 ■• Grades to very dense 75 75 0 W 5015" ■ 0 I N 80 O 80 N - 0 Note: See Figure A-2 for explanation of symbols � LOG OF BORING Geo��Engineers FIGURE A-4 TEST DATA BORING B-21 (Continued) DESCRIPTION Moisture Dry Content Density Blow Group Lab Tests (%) (pcf) Count Samples Symbol 80 80 SP Gray fine to medium sand with occasional fine gravel(dense to very dense,wet) 22* 85 85 MD 10 131 50/5" Boring completed at 89.0 feet on 12/10/96 90 Ground water encountered at 9.0 feet during drilling 90 *Note: Blow count may not be representative due to heave during sampling 95 95 Uj w w w Z a. F- p100 100 105 105 to rn 0 M N 110 110 U N 0 115 115 O M cD O `14 120 O 120 N O Note: See Figure A-2 for explanation of symbols keLOG OF BORING al Geo� -...En gineers FIGURE A-4 Cone Penetration Test - CPT-1 Test Date:Dec 09,1996 Operator :Northwest Cone Exploration Ground Surf.Elev. : 18.0 Location :Building 25-20,Boeing Longacres,Renton,WA Water Table Depth:9.0 at (tsf) Fr. Ratio (%) PWP (tsf) Ic N1(60) (blows/ft) 00 150 300 450 600 750 0 1 2 3 4 5 -1 0 1 2 3 4 0.5 1.0 1.5 2.0 2.5 3.0 0 15 30 45 60 75 8 16 24 32 now— N N c 40 L Q 48 56 64 72 1 80 Qt normalized for Fr Ratio a 100'F/(Qt-Sigmav) After Jeff—and Davies(1991) After Jeff—es and Davies(1993) unequal end area effects Gamma-115 Pelf Ic<1.25-Gravelly sands 1.25 de<1.90-Clean to silty sand 1.90<lc<2.54-Silly sand to sandy silt 2.54<lc<2.82-Clayey silt to silly clay D 2.82<c<3.22-Clays cn PROJECT NO.0120-214-06 DATE:December 12,1996 DRAWN BY:Keith Brown GeoEngineers Cone Penetration Test - CPT-2 Test Date:Dec 09, 1996 Operator :Northwest Cone Exploration Ground Surf.Elev. : 16.0 Location :Building 25-20,Boeing Longacres,Renton,WA Water Table Depth:9.0 Qt (tsf) Fr. Ratio (%) PWP (tsf) Ic N1(60) (blows/ft) 0 150 300 450 600 750 0 1 2 3 4 5 -1 0 1 2 3 4 0,5 1.0 1.5 2.0 2.5 3.0 0 15 30 45 60 75 8 16 24 32 —, SO N 1 N c 40 L a a 48 56 64 72 80 Qt normalized for Fr Ratio-100+F/(Qt-Sigmav) After Jefferies and Davies(1991) After Jefferiea and Davies(1993) unequal end area effects Gamnta—115 pef Ic<1.25-Gravelly wands 1.25 do<1,90-Clean to silty sand 1.90 do<2.54-Silty nand to sandy silt D 2.54<Ic<2,82-CIyey silt 1.silty Clay 2.82<lc<3.22-Clays PROJECT NO.0120-214-06 DATE:December 12,1996 DRAWN BY:Keith Brown GeoEngineers Cone Penetration Test - CPT-3 Test Date:Dec 09, 1996 Operator :Northwest Cone Explorations Ground Surf.Elev. : 16.5 Location :Building 25-20,Boeing Longacres,Renton,WA Water Table Depth:9.(' at (tsf) Fr. Ratio (%) PWP (tsf) Ic N1(6O) (blows/ft) 0 150 300 450 600 750 0 1 2 3 4 5 -1 0 1 2 3 4 0.5 1.0 1.5 2.0 2.5 3.0 0 15 30 45 60 75 0 6 16 24 N 32 is � 1 N 1 c_ 40 Q N 48 56 64 1 1 72 1 80 Qt normalized for Fr RaLioa 100'F/(Qt-Sigmav) After Jefferiesmid Davies(1991) After Jefferiesand Davies(1993) unequal end area effects Gamma:115 pef Ic<1.25-Gravelly sands 1.25<le<1.90-Clean to silty sand 1.90<lc<254-Silty wand to sandy sill 2.54<Ic<2.82-Clayey sill to silty clay D 2.82<Ic<3.22-Clays I V PROJECT NO.0120-214-06 DATE:December 12,1996 DRAWN BY:Keith Brown GeoEnglneers Cone Penetration Test - CPT-4 Test Date:Dec 11,1996 Operator :Northwest Cone Exploration Ground Surf.Elev. : 17.0 Location :Building 25-20,Boeing Longacres,Renton,WA Water Table Depth:9.0 Qt (tst) Fr. Ratio (%) PWP (tst) Ic N1(60) (blows/tt) 00 150 300 450 600 750 0 1 2 3 4 5 -1 0 1 2 3 4 0.5 1.0 1.5 2.0 2.5 3.0 0 15 30 45 60 75 8 16 24 32 CD N 1 c_ 40 Q O O 48 1 56 64 MP- 1 72 1 80 Qt normalized for Fr Ratio-100-r/(Qt-Sigma,) After Jeffenes and Davies(1991) After Jeffenes and Davies(1993) unequal end area effects Gamma e 115 pef le<1.25-Gravelly sands 1.25<Ic<1.90-Clean to silty sand 1.90<lc<254•Silty sand to sandy sill 2.54<lc<2.82-Clayey silt to silty clay 2.82 do<3.22-Clays I c PROJECT NO.0120-214-06 DATE:December 12,1996 DRAWN BY:Keith Brown GeoEngineers Cone Penetration Test - CPT-5 Test Date:Dee 11,1996 Operator :Northwest Cone laploration Ground Surf.Elev. :16.5 Location :Building 25-20,Boeing Longacres,Renton,WA Water Table Depth:7.0 at (tsf) Fr. Ratio (%) PWP (tsf) Ic N1(60) (blows/ft) 00 150 300 450 600 750 0 1 2 3 4 5 -1 0 1 2 3 4 0.5 1.0 1.5 2.0 2.5 3.0 0 15 30 45 60 75 8 16 ' 24 N 32 � 1 N c_ 40 L Q N 48 56 I 1 64 72 1 80 Qt normalized for Fr Ratio-100*F/(Qt-Sigmav) After Jefferies and Davies(1991) After Jefferieg and Davies(1993) unequal end area effects Gamma m 115 pcf Ic<1.25-Gravelly sands 1.25<lc<1.90-Clean to silty sand 1.90<Ic<254-Silty sand to sandy gilt D 2.54<Ic<2.82-Clayey silt to silty clay l 2.82<1c<3.22-Clays PROJECT NO,0120-214-06 DATE:December 12,1996 DRAWN BY:Keith Brown GeoEnglrleerS Cone Penetration Test - CPT-6 Test Date:Dec 11, 1996 Operator :Northwest Cone Exploration (,round Surf.I lev. : 15.0 Location :Building 25-20,Boeing Longacres,Renton,WA Water Table Depth:7.0 Qt (tsf) Fr. Ratio (%) PWP (tsf) Ic N1(60) (blows/ft) 00 150 300 450 600 750 0 1 2 3 4 5 -1 0 1 2 3 4 0.5 1.0 1.5 2.0 2.5 3.0 0 15 30 45 60 75 8 16 24 ab N 32 cow N N c_ 40 L Q 48 56 64 72 80 Qt normalized for Fr Ratio=l00'F/(Qt-Sigmav) Afterlefferics acid Davies(1991) After lefferies and Davies(1993) unequal end area effects Gamma=115 Pelf Ic<1.25-Grav6ly sands 1.25<lc<1.90-Clean to silty sand 1.90<Ic<254-Silty sand to sandy sill D 2.54<lc<2.82-Clayey silt to silty clay 1 2.82<lc<3.22-Gays PROJECT NO,0120-214-06 DATE:December 12,1996 DRAWN BY:Keith Brown GeoEngineers i Cone Penetration Test - CPT-7 Test Date:Dec 09,1996 Operator :Northwest Cone Exploration Ground Surf.Elev.: 16.0 Location :Building 25-20,Boeing Longacres,Renton,WA Water Table Depth:9.0 at (tsf) Fr. Ratio (%) PWP (tsf) Ic N1(60) (blows/ft) 00 150 300 450 600 750 0 1 2 3 4 5 -1 0 1 2 3 4 0.5 1.0 1.5 2.0 2.5 3.0 0 15 30 45 60 75 B 16 24 N 32 m N c_ 40 L_ Q 48 56 64 72 80 Qt normalized for Fr Ratio=100•F/(Qt-Sigmav) After Jefferies and Davies(1991) After Jeffenes and Davies(1993) unequal end area effects Gamma:115 pcf lc<1.25-Gravelly sands 1.25<lc<1.90-Cl-n to silty sand 1.90<lc<2.54-Silty Rand to sandy silt D 2.54<lc<2.82-Clayey silt to silty clay 1 2.82<lc<3.22-Clays PROJECT NO.0120-214-06 DATE:December 12.1996 DRAWN BY:Keith Brown GeoEngineers LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TEST PIT TT-3 Approximate ground surface elevation: 16.2 feet 0.0- 0.5 SM Brown silty fine to medium sand with occasional fine gravel(loose, moist)(fill) 0.5- 3.5 SM Black silty fine sand with occasional gravel,organic matter and construction debris (medium dense,moist)(fill) 3.5- 11.0 ML Gray silt with occasional fine sand and organic matter(medium stiff, moist) 11.0- 15.0 SM Brown silty fine sand(medium dense,moist) Test pit completed at 15.0 feet on 12/11/96 Ground water seepage observed at 8.0 feet Minor caving observed at 8.0 feet Disturbed soil samples obtained at 0.5,2.0,4.0, 10.5 and 12.5 feet TEST PIT TP4 Approximate ground surface elevation: 15.0 feet 0.0- 1.5 SM Brown silty fine to medium sand with occasional gravel and construction debris (loose to medium dense,moist)(fill) 1.5- 1.7 Wood chips intermixed with fine sand(fill) 1.7- 7.5 ML Brown and gray silt with occasional fine sand(medium stiff, moist) 7.5- 12.0 ML Gray fine sandy silt(soft to medium stiff, wet) Test pit completed at 12.0 feet on 12/11/96 Ground water seepage observed at 8.0 feet Severe caving observed at 5.0 to 12.0 feet Disturbed soil samples obtained at 0.5, 1.0, 1.5,2.0,2.5,3.0,4.0 and 8.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. 'p• LOG OF TEST PIT G e o Engineers FIGURE A-12 0 LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TEST PIT TP-5 Approximate ground surface elevation: 15.0 0.0- 0.5 SP Brown fine to medium sand with occasional organic matter(loose, moist)(fill) 0.5- 1.0 SM Gray silty fine sand with occasional fine gravel(dense,moist)(fill) 1.0- 8.0 ML Brown and gray silt with occasional fine sand(medium stiff, moist) 8.0- 10.5 SM Gray silty fine sand with occasional organic matter(loose to medium dense,wet) 10.5- 13.0 SP Black fine sand(loose to medium dense,wet) Test pit completed at 13.0 feet on 12/11/96 Ground water seepage observed at 8.0 feet Severe caving observed at 5.0 feet Disturbed soil samples obtained at 0.5, 1.0,2.0,7.0, 10.5 and 13.0 feet TEST PIT TP-6 Approximate ground surface elevation: 14.0 feet 0.0- 1.0 SP Brown fine to medium sand(loose,moist)(fill) 1.0- 1.5 SM Gray silty fine sand with occasional fine gravel(medium dense,moist)(fill) 1.5- 6.0 ML Brown and gray silt with occasional fine sand(soft to medium stiff, moist) 6.0- 11.0 SM/ML Interbedded layers of gray silt with occasional fine sand and black silty fine sand (medium stiff/medium dense,moist to wet) 11.0- 14.0 SP Black fine sand(medium dense,wet) Test pit completed at 14.0 feet on 12/11/96 Ground water seepage observed at 7.0 feet No caving observed Disturbed soil samples obtained at 1.0, 1.5,2.0,4.0, 11.5 and 13.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. (N� LOG OF TEST PIT Geo W144W neers FIGURE A-13 LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TESL'PIT TP-7 Approximate ground surface elevation: 15.5 feet 0.0- 0.5 Beauty bark 0.5- 1.0 Quarry spalls 1.0- 2.0 SM Gray silty fine sand(medium dense,moist)(fill) 2.0- 12.0 ML Gray and brown silt(soft to medium stiff, moist) Test pit completed at 12.0 feet on 12/11/96 Ground water seepage observed at 7.0 feet No caving observed Disturbed soil samples obtained at 1.5 and 9.0 feet TEST PIT TP-8 Approximate ground surface elevation: 15.5 feet 0.0- 1.0 SM Brown silty fine sand with occasional organic matter(loose, moist)(fill?) 1.0- 8.0 ML Brown and gray silt with occasional fine sand and organic matter(soft to medium stiff, moist) 8.0- 9.5 SM Gray silty fine sand(loose to medium dense,wet) Test pit completed at 9.5 feet on 12/11/96 Ground water seepage observed at 8.0 feet Severe caving observed at 5.0 feet Disturbed soil samples obtained at 2.0 and 4.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. LOG OF TEST PIT Geo l o JLJL%- FIGURE A-14 DEPTH BELOW SOIL GROUP LOG OF TEST PIT GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TESL'PIT TP-9 Approximate ground surface elevation: 17.0 feet 0.0- 3.5 SM Brown and gray silty fine sand with occasional fine gravel and organic matter(loose to medium dense,moist)(fill) 3.5- 10.0 SM/ML Intermixed layers of gray silty fine to medium sand with occasional gravel and organic matter and brown silt(loose to medium dense,moist)(fill) 1-foot-diameter log encountered at 5.0 feet 10.0- 11.0 ML Brown and gray silt with occasional fine sand(medium stiff, wet) Test pit completed at 11.0 feet on 12/11/96 Ground water seepage observed at 7.0 feet Severe caving observed at 5.0 feet Disturbed soil samples obtained at 1.5,3.0 and 11.0 feet TEST PIT TP-10 Approximate ground surface elevation: 16.0 feet 0.0- 1.0 SM Dark brown silty fine sand with occasional organic matter(loose, wet) (fill) 1.0- 7.0 ML Brown and gray silt with occasional fine sand and organic matter(soft to medium stiff, moist) 7.0- 10.0 ML Gray silt(soft, wet) 10.0- 11.5 SM Brown silty fine sand(loose to medium dense,wet) Test pit completed at 11.5 feet on 12/11/96 Ground water seepage observed at 7.0 feet Moderate caving observed at 1.0 foot Disturbed soil samples obtained at 4.0,7.0 and 10.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. ����, LOG OF TEST PIT GeowviEngineers FIGURE A-15 LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TEST PIT TP-11 Approximate ground surface elevation: 16.0 feet 0.0- 1.5 SM Brown silty fine sand with gravel and occasional cobbles and organic matter(loose, moist)(fill) 1.5-4.0 SP/ML Intermixed brown silt and black fine sand with occasional gravel(medium stiff/loose to medium dense,moist)(fill) 4.0-5.5 ML Gray silt(soft to medium stiff, moist) 5.5-9.5 SP Black fine sand(loose to medium dense,moist to wet) Test pit completed at 9.5 feet on 12/11/96 Ground water seepage observed at 8.0 feet Severe caving observed at 5.5 feet Disturbed soil samples obtained at 1.0,2.0 and 9.0 feet TEST PIT TP-12 Approximate ground surface elevation: 15.0 feet 0.0-0.5 SM Brown silty fine sand with occasional organic matter(loose, moist)(fill) 0.5-0.7 Crushed rock 0.7- 1.0 SM Brown silty fine to medium sand with occasional gravel (loose to medium dense, moist)(fill) 1.0-3.0 ML Brown and gray silt with occasional organic matter(medium stiff, moist) 3.0-9.5 SM Brown and gray silty fine sand with occasional organic matter (loose to medium dense,moist to wet) Test pit completed at 9.5 feet on 12/11/96 Ground water seepage observed at 8.0 feet Severe caving observed at 5.0 feet Disturbed soil samples obtained at 3.5 and 8.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. LOG OF TEST PIT Geo� p Engineers FIGURE A-16 LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TEST PIT TP-13 Approximate ground surface elevation: 17.0 feet 0.0- 1.0 SM Brown and gray silty fine sand with occasional fine gravel and organic mater (medium dense,moist)(fill) 1.0- 5.0 ML Brown and gray silt with fine sand(medium stiff, moist)(fill?) 5.0- 11.0 SM Brown silty fine sand(loose,wet)(fill) 11.0- 11.5 Wood chips intermixed with fine sand(fill?) 11.5- 12.0 SP Black fine sand(loose to medium dense,wet) Test pit completed at 12.0 feet on 12/12/96 Ground water seepage observed at 7.0 feet Severe caving observed at 8.0 feet Disturbed soil samples obtained at 0.2, 1.0,2.0, 5.5, 11.5 and 12.0 feet TEST PIT TP-14 Approximate ground surface elevation: 16.5 feet 0.0- 1.0 SM Brown silty sand with occasional fine to coarse gravel and organic matter (loose, moist)(fill) 1.0- 7.0 ML Brown and gray silty with fine sand and occasional organic matter(medium stiff, moist) 7.0- 11.0 SP Black fine sand with interbedded layers of silt(loose to medium dense,wet) Test pit completed at 11.0 feet on 12/12/96 Ground water seepage observed at 8.0 feet Severe caving observed at 8.0 feet Disturbed soil samples obtained at 2.0 and 11.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. ga LOG OF TEST PIT G e o Engineers FIGURE A-17 LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TEST PIT TP-15 Approximate ground surface elevation: 16.5 feet 0.0- 1.0 SM Brown silty fine sand with occasional fine gravel and organic matter(loose, moist) (fill) 1.0- 6.5 ML Brown and gray silt with occasional fine sand and organic matter (medium stiff, moist) 6.5- 10.0 SM Brown silty fine sand(loose to medium dense,moist) 10.0- 11.5 SP Black fine sand(medium dense,moist) Test pit completed at 11.5 feet on 12/12/96 No ground water seepage observed Moderate caving observed at 8.0 feet Disturbed soil samples obtained at 2.0,4.0 and 11.0 feet TEST PIT TP-16 Approximate ground surface elevation: 15.0 feet 0.0- 2.5 SM Brown and gray silty fine sand with occasional fine gravel and organic matter(loose to medium dense,moist)(fill) Geotextile encountered at 0.7 foot 2.5- 6.0 ML Brown and gray silt with occasional fine sand(medium stiff, moist) 6.0- 9.0 SP Black fine sand(loose to medium dense,wet) Test pit completed at 9.0 feet on 12/12/96 Ground water seepage observed at 6.5 feet Severe caving observed at 6.0 feet Disturbed soil samples obtained at 1.5,2.5 and 9.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. LOG OF TEST PIT Geo 441 001EngmL1,(,71ers FIGURE A-18 LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TEST PIT TP-17 Approximate ground surface elevation: 15.0 feet 0.0- 0.5 SM Brown silty fine sand with organic matter(loose to medium dense,moist)(fill) 0.5- 1.0 Crushed rock 1.0- 7.0 ML Brown and gray silt with occasional fine sand and organic matter (medium stiff, moist) 7.0- 12.5 SM Gray silty fine sand(loose to medium dense,wet) Test pit completed at 12.5 feet on 12/12/96 Ground water seepage observed at 7.0 feet Severe caving observed at 8.0 feet Disturbed soil samples obtained at 2.0, 3.0, 8.0 and 12.0 feet TEST PIT TP-18 Approximate ground surface elevation: 15.5 feet 0.0- 1.5 Brown silty fine to medium sand with fine to coarse gravel and occasional organic matter(loose to medium dense,moist)(fill) 1.5- 6.5 ML Brown and gray silt with occasional organic matter(medium stiff, moist) 6.5- 8.5 SM Black silty fine sand(loose to medium dense,wet) Test pit completed at 8.5 feet on 12/12/96 Ground water seepage observed at 6.5 feet Moderate caving observed at 2.0 feet Disturbed soil sample obtained at 8.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. LOG OF TEST PIT Geov.1.Engineers FIGURE A-19 LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TEST PIT TT-19 Approximate ground surface elevation: 17.5 feet 0.0- 0.5 SM Brown silty fine to medium sand with fine to coarse gravel and a trace of organic matter(medium dense,moist)(fill) 0.5- 1.0 Wood chips intermixed with silty fine sand(loose,moist)(fill) 1.0- 2.5 SM Gray silty fine sand with occasional fine gravel(medium dense,moist)(fill) 2.5- 8.0 ML Brown and gray silt with occasional fine sand and organic matter (medium stiff, moist) 8.0- 12.0 SP Dark brown fine sand(medium dense,wet) Test pit completed at 12.0 feet on 12/12/96 Ground water seepage observed at 9.0 feet Severe caving observed at 6.5 feet Disturbed soil samples obtained at 1.0, 1.5,2.0,2.5,4.0 and 6.0 feet TEST PIT TP-20 Approximate ground surface elevation: 12.5 feet 0.0- 2.0 SM Brown silty fine sand with occasional fine gravel and organic matter (loose to medium dense,moist)(fill) 2.0- 5.0 ML Brown and gray silt with occasional fine sand and organic matter(medium stiff, moist) 5.0- 9.0 SM/ML Interbedded layers of gray silty fine sand and fine sandy silt (loose/soft, moist to wet) 9.0- 12.0 SP Black fine sand(medium dense,wet) Test pit completed at 12.0 feet on 12/12/96 Ground water seepage observed at 8.0 feet Severe caving observed at 7.0 feet Disturbed soil samples obtained at 3.0,7.0 and 12.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. /����. LOG OF TEST PIT Geo%l,�Engineers FIGURE A-20 LOG OF TEST PIT DEPTH BELOW SOIL GROUP GROUND SURFACE CLASSIFICATION (FEET) SYMBOL DESCRIPTION TEST PIT TP-21 Approximate ground surface elevation: 12.5 feet 0.0- 1.5 SM Brown and gray silty fine sand with occasional fine gravel(dense,moist)(fill) 1.5- 7.0 ML Brown and gray silt with occasional organic matter(soft to medium stiff, moist) 7.0- 11.0 SM Gray silty fine sand(loose to medium dense,wet) Test pit completed at 11.0 feet on 12/12/96 Ground water seepage observed at 5.0 feet Severe caving observed at 6.0 feet Disturbed soil samples obtained at 0.5, 1.5,2.5,4.0 and 8.0 feet TEST PIT TP-22 Approximate ground surface elevation: 15.0 feet 0,0- 0.2 Crushed rock 0.2- 0.6 Quarry spalls 0.6- 1.5 SM Brown silty fine to medium sand with fine to coarse gravel(dense,moist)(fill) 1.5- 7.5 ML Brown and gray silt with occasional organic matter(medium stiff, moist) 7.5- 11.5 SM Brown and gray silty fine sand(medium dense,moist) Test pit completed at 11.5 feet on 12/12/96 Ground water seepage observed at 9.5 feet No caving observed Disturbed soil samples obtained at 1.0,3.0,8.0 and 10.0 feet THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT. LOG OF TEST PIT Geo`�Engineers FIGURE A-21 APPENDIX B APPENDIX B LABORATORY TESTING Soil samples obtained from the borings and test pits were sealed and returned to our laboratory for further examination and testing. Selected samples from the borings and test pits were tested to determine their moisture content, dry density, and grain size distribution. The results of the moisture content and dry density determinations on the samples obtained from the borings are presented on the boring logs. The results of moisture content determinations on the samples obtained from the test pits are presented in Figure B-1. The grain size distribution tests are presented in Figures B-2 through B-3. G e o E n g i n e e r s B - 1 File No.01 20-2 1 4-06-1 130/0 10797 MOISTURE CONTENT DATA Test Depth of Moisture Pit Sample Soil Content Number (feet) Classification M 3 2 SM 20 4 1 SM 13 4 2 ML 34 4 8 ML 34 5 1 SM 9 5 10.5 SM 34 6 1.5 SM 9 7 1.5 SM 12 9 3 SM 15 10 4 ML 42 10 10 ML 37 11 2 SP 18 12 3.5 SM 28 13 1 SM 13 13 5.5 SM 26 14 2 ML 33 15 4 ML 41 16 2.5 SM 32 17 2 ML 35 19 1.5 SM 25 19 2.5 SM 21 19 6 ML 30 20 3 M L 40 21 0.5 SM 5 21 2.5 ML 54 22 1 .3 SM 6 22 3 ML 37 MOISTURE CONTENT DATA Geo �Engineers FIGURE B-1 0120-214-06T1 SDS:GMD:cms 12/30/96 (P:\GRAIN.PRE) U.S. STANDARD SIEVE SIZE 3" 1.5" 3/4" 3/8" #4 #10 #20 #40 #60 #100 #200 100 — 90 80 70 Ej- CAD 60 CD co CD U) 50 < z 40 aw 30 20 10 G) 0 -n 0 1,000 100 10 1 0.1 0.01 0.001 5 > GRAIN SIZE IN MILLIMETERS C: X 0 m z GRAVEL SAND 0 COBBLES I I SILT OR CLAY C: I COARSE I FINE 1COARSE1 MEDIUM FINE m (n SYMBOL EXPLORATION SAMPLE SOIL DESCRIPTION NUMBER DEPTH(FEET) B-20 63 Gray fine gravel with fine to coarse sand (GP) ♦ B-21 18 Black fine sand (SP) PERCENT FINES DATA Depth of Percent Exploration Sample Soil Fines Number (feet) Classification M) B-20 13 SM 35 B-21 13 SM 48 TP-4 8 ML 59 TP-5 10.5 SM 46 TP-7 1.5 SM 25 TP-10 10 ML 52 �p PERCENT FINES DATA G e o. Engineers FIGURE B-3 APPENDIX C APPENDIX C LOGS OF EXPLORATIONS FROM PREVIOUS STUDIES G e o E n g i n e e r s C - 1 File No. 0120-214-06-1130/010797 l�rDATA BORIl G 5 r +� m � r � 4jt ~ su a 4 3 a DESCRIPTION +C C p O J E Group m 00 s J FU W 0 -a 0 4 S}mbol Surface Elevation(ft.): 13.70 .. 00 . ©U to 0 rnchcs asphalt concrete underlain by brown silty fine to medium 0 t MI sand(medium dense,moist)(fill) Dark gray silt with a trace of sand (soft to medium stiff,moist) MD 34 87 4 ■ F 5 5 SM/ Dark gay silty fine sand to silt With sand(ver)-loose,soft,wet) 2 ■ is 10 Z0 f SP Black fine sand with a trace of silt(very loose to loose,a et) a A.D 31 91 4 ■ 15 w 15 w w Y � � 11 ■ H IL r ❑ 20 t SP Black fine to medium sand with a trace of silt(dense,wet) 20 �. MD, 22 103 31 ■ 6TXI a GS 25 M �5 c� ❑ '9 ■ Grades to sand v.ith fine gravel to Q 30 i� 30 J L 40 ■ 35 35 @ W t!1 , 21 ■ rn m t i 40 40 Note:See Figure A-2 for explana on of symbols 1 Aug• Log of Boring Geo\�Engineers Figure A-12 _ C-1 =—T DATA BORING 5 a (Continued) . L4.) r 01: r F 4j r 9 DESCRIPI-ION •p C^ 3 C p 0 7 E Group f o o� Lila —4 o r Svmbol J ,a40 - SP ark gray fine to medium sand with shell fragments(medium dense,wet) 23 45 45 23 50 SW/ Gray gravelly fine to coarse sand to sandy fine to coarse gravel $0 dense,w-et) MD 10 lil 50 — 4. — _ = r w - - L1 LL — — Z — - - 45 — — F=- Boring completed at 58S feet on 12/3/90 60 Groundwater encountered at a depth of about 6 feet during drilling 60 m m N \ 65 65 N M U N C U 70 70 J Z 75 75 1D m m m m a so 80 m Note:See Figure A-2 for explanation of symbols Log of Boring Geo�ft Engineers _ Figure A-13 c-' TEST DATA BORING H m � r i tJa� ] II DESCRIYI'l ON Iw r D 3 C a Group 0 0 X e a �+ 0 i S}�rrbl Surface Elevation(ft.): 16.43 J LUG C)C O U N 0 ML rcr%mish-gray sandy silt with a trace of organic matter(medium 0 stiff,moist)(fill?) 8 5 5 SP Black fine to medium sand (loose to medium dense,wet) 6 0 10 10 MD 26 92 s ■ _ 15 15 F LU W tL Z H S 11 ® Grades to medium sand F a LOU 20 20 m g Grades to fine sand m a 25 25 N N 0 21 ■ cal 30 30 J z -_ 9 ® Grades to with occasional wood fragments 35 35 SP Gray fine to medium coarse sand with a trace of fine gravel (dense,wet) to m t m 3 ■ Oi m t N 40 40 m Note:See Figure A-2 for explanation of symbols its Log of Boring Geo*,,�&r Engineers Figure A-18 c-2 s TEST DATA BORI G 8 r (Continued) DESCRIPTION r 3 C tl Group i o o x L ICa --+o i Symbl J ZU. 00- 0U to 40 40 35 SP— Gray fine to medium sand nth silt(dense,wet) SM 45 SP Gray medium sand arith occasional shell fragments(medium 45 dense,wet) MD 22 104 25 , SM Gray fine to medium silty sand with occasional shell fragments (medium dense,wet) 50 50 SW Gray fine to coarse sand v ith a trace of silt,occasional gavel and _ = shell fragments(dense,wet) 42 — 55 H - W W LL H - _ 32 — ~ Boring completed at 59.0 feet on 12/7/90 IL LLJ 60 Ground Rater encountered at approximately 5 feet during drilling 60 m rn 65 65 N N F U N c¢i 70 70 F. J Z 75 75 LO Ill i m U) m 80 80 N m Note:See Figure A-2 for explanation of symbols Wi Lo t/ g of Boring Geo tsvco Engineers Figure A-19 C-2 s _. TEST DATA MONITOR WELL MW-32 DESCRIPTION Moisture Dry o e Group Content Density GNU Symbol Approzimate Surface Elevation(M 15.6 Lab Tesu (%) f) S 0 ML Brownish gray silt with a tract of fine sand(soft,moist to wet) 0 5 5 10 10 : SP Gray medium sand with fine sand(loose to medium dense,wet) 15 15 t— - w w Z 71 a Q 20 No samples obtained during drilling 20 - Boring completed at 20.0 feet on 08/07/91 U Ground water encountered at 12.0 feet during drilling 3/4-inch-diameter piezometer installed to 20.0 feet 25 25 0 � 30 30 35 35 d 40 40 Note:See Figure A 2 for explanation of symbols Log of Monitor Well GeA �Engineers Figure A-15 C-3