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GEOTECHNICAL DATA AND DESIGN REPORT

STANLEY BOULEVARD

SAFETY AND STREETSCAPE IMPROVEMENT PROJECT

BETWEEN THE CITY LIMITS OF PLEASANTON AND LIVERMORE, CALIFORNIA

29 JUNE 2010

Prepared for:

Alameda County Public Works Agency

399 Elmhurst Street

Hayward, California 94544

Prepared by:

Cal Engineering & Geology, Inc.

119 Filbert Street

Oakland, California 94607


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Geotechnical Data and Design Report Stanley Boulevard Improvements

090250.002 Cal Engineering & Geology, Inc.

TABLE OF CONTENTS

1.0 INTRODUCTION ..................................................................................................................1

2.0 SCOPE OF WORK .................................................................................................................23.0 SITE AND PROJECT DESCRIPTION..................................................................................34.0 GEOLOGY AND SOILS .......................................................................................................4

4.1 REGIONAL GEOLOGY ................................................................................................4

4.2 SITE GEOLOGY ............................................................................................................4

4.3 SURFICIAL SOILS ........................................................................................................44.4 SUBSURFACE CONDITIONS ......................................................................................54.5 TECTONIC SETTING ....................................................................................................54.6 SEISMICITY ...................................................................................................................5

5.0

EXPLORATION AND TESTING PROGRAM ....................................................................7

5.1 UTILITY POTHOLING .................................................................................................75.2 EXPLORATORY BORINGS .........................................................................................75.3 LABORATORY TESTING ............................................................................................85.4 PERCOLATION TESTING ............................................................................................85.5 SOIL TREATMENT AND FERTILITY ANALYSIS ...................................................8

6.0 GEOTECHNICAL DESIGN CONSIDERATIONS ............................................................106.1 GENERAL ....................................................................................................................106.2 SEISMIC HAZARDS ...................................................................................................11

7.0 ENGINEERING ANALYSES..............................................................................................147.1 STABILITY ANALYSES ............................................................................................14

8.0 DESIGN AND CONSTRUCTION RECOMMENDATIONS .............................................178.1 DESIGN RECOMMENDATIONS ...............................................................................178.2 CONSTRUCTION RECOMMENDATIONS ..............................................................22

9.0 LIMITATIONS .....................................................................................................................2510.0 REFERENCES .....................................................................................................................26TABLE 1. ACTIVE FAULTS .........................................................................................................6

TABLE 2. BACK CALCULATED SOIL COHESION RESULTING IN VARIOUS

FACTORS OF SAFETY ......................................................................................................15

TABLE 3. MSE RETAINING WALL DESIGN SOIL PARAMETERS .....................................18

TABLE 4. PILE AND PILE CAP DESIGN PARAMETERS ......................................................19

TABLE 5. CIDH PILE DESIGN PARAMETERS .......................................................................20

TABLE 6. CONCRETE AND MASONRY RETAINING WALL DESIGN PARAMETERS ...21

FIGURE 1. SITE LOCATION

FIGURE 2. TYPICAL SECTION

FIGURE 3. SITE GEOLOGY


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FIGURE 4. SURFICIAL SOILS

FIGURE 5. SEISMIC HAZARDS

FIGURE 6. SITE PLAN AND BORING LOCATIONS

FIGURE 7. LOADING DIAGRAMS

APPENDIX A. BORING LOGS

APPENDIX B. PERCOLATION TEST DATA

APPENDIX C. SOIL TREATMENT AND FERTILITY ANALYSIS

APPENDIX D. SLOPE STABILITY ANALYSES RESULTS


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1.0 INTRODUCTIONAlameda County Public Works Agency is proposing to improve the safety and visual aestheticsof Stanley Boulevard between the city limits of Pleasanton and Livermore in an unincorporated

area of Alameda County. Project elements include undergrounding the existing aerial utilities,

constructing a multi-use pathway along the south side of the roadway, constructing Class II bike

lanes, streetscaping, reconstructing the existing median to incorporate landscaping (trees &

ground cover), modifying existing highway lighting and traffic signal systems, improving the

drainage system, and pavement reconstruction and slurry seal in appropriate areas to

accommodate these improvements. In the vicinity of Shadow Cliffs Regional Recreation Area,

the project will include the construction of a retaining wall to both provide a level pad for a new

pathway and to protect the path against erosion which could damage the pathway. The project

will improve pedestrian and bicyclist access as well as improve the visual aesthetics along

Stanley Boulevard.

The purposes of this Geotechnical Data and Design Report are to develop information regarding

the surface and subsurface soil conditions near the proposed improvements and to provide

geotechnical engineering recommendations for the planned project.


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2.0 SCOPE OF WORKThe services completed in developing this Geotechnical Data and Design Report included the

following:

Coordinating with County staff and project consultants; Reviewing published soil and geologic maps of the area; Reviewing previous geotechnical reports prepared for the site; Drilling and sampling of three exploratory borings; Evaluating the materials encountered in the borings; Conducting laboratory and field testing of selected samples recovered from the borings; Completing eight on-site percolation tests and obtaining samples for soil chemistry and

fertility testing;

Subcontracted soil chemistry and fertility analysis; Performing engineering analyses; and Developing geotechnical design parameters for the project.This report presents the results of the review of available data, field exploration, laboratory

testing program, and engineering analysis, and geotechnical design considerations and

recommendations pertaining to the design and construction of the proposed project. Evaluation

or identification of the potential presence of hazardous materials at the site was not requested and

was beyond the authorized scope of this project. Our investigation has been specifically limited

to developing information regarding the geotechnical conditions within the vicinity of the areas

of the proposed improvements.


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3.0 SITE AND PROJECT DESCRIPTIONAlameda County Public Works Agency is planning to improve the safety and visual aesthetics of

Stanley Boulevard between the City Limits of Pleasanton and Livermore in an unincorporated

area of Alameda County as shown in Figure 1. Stanley Boulevard is a four lane arterial that

trends east-west and provides access between downtown Livermore and Interstate 580 to the east

and downtown Pleasanton and Interstate 680 to the west.

As part of the project, Stanley Boulevard will be widened and a multi-use pathway will be

constructed on the south side of the road. One segment of the project is to be located at the crest

of a cut slope, which was excavated on the south side of the road during quarrying activities

which took place prior to the 1970s. The cut slope has inclinations between 2H:1V (horizontal:

vertical) to 0.8H:1V. The quarry pit was eventually filled with water, deeded over to the East

Bay Regional Park District (EBRPD), and became Shadow Cliffs Lake and the Shadow Cliffs

Regional Recreation Area. Based on our discussions with East Bay Regional Park District

personnel and County personnel, it is our understanding that the quarry pit was over 115 feet

deep prior to being filled to within 50 feet of the top of the cut. The lake was reportedly filled

circa 1972.

A retaining wall is to be constructed at the top of the slope in order to create a level area to

accommodate the road widening and pathway. The bottom of the wall will be located on the cut

slope and will have either a leveling pad or a pile and pile cap foundation. The retaining wall

will be approximately 1,900 feet long and will vary in height from 4 feet to up to 12 feet tall.

Typical cross sections of the roadway and retaining wall configurations are shown in Figure 2.

Several bioswales are also planned along the side of the road to mitigate storm water runoff from

the roadway. The bioswales will consist of aV shaped earth ditch through though which

water will percolate and then enter a subdrain system which will then discharge into the storm

drain facility.


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4.0 GEOLOGY AND SOILS4.1 REGIONAL GEOLOGYThe project site is located within Californias Coast Ranges province. The province includes

many separate ranges, coalescing mountain masses, and several major structural valleys shaped

primarily by tectonic forces. The Coast Ranges are long series of north-west trending ranges

separated by parallel river valleys. Some of the prominent ranges within the province include the

Mendocino Range to the north, Diablo Range to the east of San Francisco, and the Santa Cruz

Mountains. The geology of this province can be defined by two distinct basement rock core

complexes adjacent to one another and separated by large magnitude faults. The first core

complex is defined by a Jurassic-Cretaceous eugeosyclinal assemblage consisting of the

Franciscan rock. The second complex is defined by Early Cretaceous granitic intrusives and

older metamorphic rocks of the Salinian block. Large portions of the province are covered in

late Cretaceous and Cenozoic sedimentary bedrock, while recent Quaternary tectonic movement

has shaped the terrain that characterize the topography today. Deposits of late Pliocene and

Pleistocene age are mainly slightly consolidated gravels, sands, and silts with some interbedded

clays. Most of the sedimentary strata are continental in origin accept those adjacent to the

present coast.

4.2 SITE GEOLOGYThe site geology in the project area has been mapped by Dibblee (1980), Nilsen (1975), and

Crane (1995). Dibblee, Nilsen, and Crane all map the site as alluvial deposits as shown in Figure

3.

4.3 SURFICIAL SOILSThe surficial soils in Alameda County have been mapped by the USDA NRCS (2009). The

NRCS map, shown in Figure 4, indicates that the project site is underlain by two soil types; Yolo

Loam and Gravel Pits.

Yolo Loam is found on 0 to 3 percent slopes and consists of alluvium comprised of clay (CL)

and silt (ML) derived from sandstone and shale. The Liquid Limit ranges between 25 and 35percent. The Plasticity Index ranges between 5 to 15 percent. The shrink-swell potential is low.

The erosion hazard is slight in cultivated areas.

The gravel pits consist of gravely sand (SG).

This mapping is consistent with the materials observed at the site and those encountered by

previous exploratory borings and our recently completed exploration.


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Table 1. Active Faults

Fault Name Fault Type Distance From Site

Calaveras Type B 7 km west-southwest

Greenville Type B 13 km northeastHayward Type A 17 km southwest

Concord-Green Valley Type B 27 km west-northwest

San Andreas Type A 47 km southwest

A large magnitude earthquake on any of these fault systems has the potential to cause significant

ground shaking at the site. The intensity of ground shaking that is likely to occur at the property

will generally depend on the magnitude of the earthquake and the distance to the epicenter. In

general, the greater the distance to the epicenter, the lesser the intensity of the ground shaking

that is anticipated to occur at the site.

4.6.2 Liquefaction and/or Earthquake Induced LandslidesIn 2008, the California Geologic Survey released a seismic hazard map of the Livermore 7.5-

Minute Quadrangle in conformance with Public Resources Code Section 2693c. The map

indicated areas where the historical occurrence of liquefaction and/or earthquake induced

landslides indicate a potential for permanent displacements. The Seismic Hazard Zone map

indicates that the road embankment above Shadow Cliffs Lake has a low potential for

liquefaction, as shown in Figure 5. However, the map does indicate that soil underlying the lake

and along the banks of the lake has the potential to liquefy during a seismic event. Additionally,

the map indicates that the east edge of the Stanley Boulevard embankment has the potential forpermanent ground displacements due to earthquake-induced landslides. This mapping is likely

due to both the steepness of the embankment (a previous quarry excavation) and the potential

liquefaction of material near the lake and its impact on global stability of the embankment.


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5.0 EXPLORATION AND TESTING PROGRAM5.1 UTILITY POTHOLINGPotholes were excavated by Subtronic to determine utility types, alignments, and elevations of

existing utilities. The results of the potholing work are summarized on plans prepared by the

Alameda County Public Works Agency. The utilities identified in the vicinity of the project

include underground gas lines, fiber optic cables, electrical lines, and storm drains.

5.2 EXPLORATORY BORINGSThe site was explored by drilling and sampling three exploratory borings on 6 May 2009. The

borings were excavated by Moore Twining Associates, Inc. using a truck-mounted drilling rig

equipped with 6-inch diameter hollow stem augers to a depth of 60 feet. All of the borings werelocated on the south side of Stanley Boulevard at the edge of the pavement. The approximate

locations of the exploratory borings are shown in Figure 6.

An engineer from our office maintained logs of the borings, visually identified and classified

soils encountered in general accordance with ASTM Standard Practice D 2488, and obtained

representative samples of the subsurface materials.

During the drilling operations, soil samples were obtained using one of the following sampling

methods:

Standard Penetration Test (SPT) Split Spoon Sampler; 2.0 inch O.D., 1.4 inch I.D. California Modified (CM) Split Spoon Sampler; 3.0 inch outer diameter (O.D.), 2.5 inch

inner diameter (I.D.)

The split spoon samplers were driven 18 inches (unless otherwise noted) into undisturbed soil

using a 30-inch drop of a 140 pound hammer. The number of blows required to drive the SPT

and CM sampler 6 inches were recorded for each sample and are included on the boring logs in

Appendix A.

The soil conditions were fairly similar in each of the borings along the alignment. The boringsgenerally encountered alluvium consisting of silty sand (SM) with gravel and clayey sand (SC)

with gravel to the depths explored. Groundwater was encountered at a depth of 50 feet which

appeared to correspond to the same elevation as the water surface on Shadow Cliffs Lake. More

detailed descriptions of the materials encountered in the borings are included on the boring logs

in Appendix A.


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Soil samples obtained from the borings were packaged and sealed in the field to reduce the

potential for moisture loss and disturbance and brought to Cal Engineering & Geologys Oakland

office for storage and potential laboratory testing.

5.3 LABORATORY TESTINGLaboratory testing was performed at the Cal Engineering & Geology soils testing laboratory in

Oakland, California to obtain information concerning the qualitative and quantitative physical

and mechanical properties of the samples recovered during the subsurface exploration program.

Tests were performed in the in general conformance with applicable ASTM standards.

Moisture and density tests (ASTM D2937) were performed on select samples from all three

borings. Based upon the tests, the materials encountered had dry densities between 118 and 133

pounds per cubic foot (pcf) and moisture contents between 4 and 10 percent. The results are

presented on the boring logs in Appendix A.

5.4 PERCOLATION TESTINGEight percolation test locations were chosen by a consultant to the County for design of the

bioswale backfill soil. The percolation tests were performed by a geologist from our office at the

chosen test locations in accordance with the analysis guidelines, Bay-Friendly Landscape Site

Analysis, published by StopWaste.org. Tests at six of the locations resulted in calculated

percolation rates between 0.41 and 1.5 inches per hour. One of the locations had an average

percolation rate of 22 inches per hour and another location drained immediately due to the

presence of animal burrows in the vicinity. Bulk samples of the soil were retained for potential

soil chemistry tests and fertility analysis. The results of the percolation tests are attached as

Appendix B.

5.5 SOIL TREATMENT AND FERTILITY ANALYSISThe bulk samples, which were retained during the percolation tests, were analyzed by Soil &

Plant Laboratory, Inc. of San Jose. The following analyses were performed:

pH electrical conductivity nitrate ammonium phosphorus potassium calcium

saturation percentage sodium chloride sodium adsorption ratio boron percent sand-silt-clay lime percentage of organics


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The analytical results and recommendations are included in a report prepared by Soil & Plant

Laboratory, which is attached as Appendix C.


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required for the retaining wall to increase global stability of the slope/wall configuration. Slope

stability analyses for the planned widening are included in Section 7.

6.1.3 ErosionThe slope below the proposed retaining wall has evidence of some minor sliding and surficial

erosion, however based on the long term performance of the embankment, no specific measures

other than hydro-seeding the areas disturbed by the contractors operations are needed.

6.1.4 GroundwaterGroundwater was encountered at depths of approximately 50 feet after drilling in the three

borings. This depth appears to be at or near the lake water surface elevation. This depth may not

necessarily reflect the groundwater surface at the time of construction.

Although the groundwater encountered is likely below the limits of construction, seasonal

variation in the water level and perched groundwater conditions can occur. The contractor

should be prepared to address the presence of groundwater regardless of when construction

occurs. It should be noted that the presence of groundwater may affect drilling and placing of

cast-in-place concrete piles. As a result the project technical specifications should include

provisions which require that the contractor anticipate and be prepared for such conditions and

that drill hole casing may be required.

6.2 SEISMIC HAZARDS6.2.1 Fault RuptureThe site is not located within an Earthquake Fault Zone for active faults as defined by the State

Geologist and the nearest mapped active fault (Calaveras) is located approximately 7 kilometers

west-southwest of the site. Therefore, the potential for surface rupture due to primary faulting at

the site is considered to be low and no specific design or construction measures are required to

address fault rupture.

6.2.2 Seismically-Induced Ground ShakingDue to the proximity of the site to numerous active fault systems which traverse the greater San

Francisco Bay Area, it is likely that the property will be subjected to the effects of a major

earthquake during the design life of the proposed improvements. The effects are likely to consist

of significant ground accelerations. These ground movements may cause damage to the

proposed improvements. This potential hazard should be taken into consideration when

designing any structural systems for the project. The retaining wall/embankment configuration

will need to be evaluated with respect to pseudostatic (seismic) slope stability. The results of the

analyses performed are presented in the Section 7.0 Engineering Analyses.


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6.2.3 LiquefactionOur exploratory drilling revealed that the project site is primarily underlain by medium dense to

dense silty sand with gravel and clayey sand with gravel to the depths explored. In general, these

materials increased in density with depth. Groundwater was observed at a depth of about 50 feet

and generally corresponded to the water surface elevation in Shadow Cliffs Lake. Although the

borings encountered dense materials at depth, less dense zones could be present, especially along

the perimeter of the lake. As a result, we judge the potential for widespread liquefaction directly

below Stanley Boulevard and the proposed improvement to be low, but there is potential for

some liquefaction to occur at below lake level. We judge that the probability of liquefaction

induced damages occurring to the planned improvements to be low to moderate. If liquefaction

of material along the edge of the lake does occur, the resulting damages are likely to be limited

to isolated portions of the improvements. As a result, we do not recommend remedial measures

be implemented to alleviate the liquefaction potential.

6.2.4 Lateral SpreadingLateral spreading is a type of ground instability that results in ground displacements that occur

when liquefaction of a soil layer causes insufficient strength for lateral stability. This

phenomenon occurs when either the ground surface or the soil layer subject to liquefaction is

sloped, or when there is an open slope face or stream channel adjacent to a potentially liquefiable

soil layer. The material encountered at and below the depth of groundwater encountered was

generally dense and not prone to liquefaction. Since the potential for deeper, less dense zones

does exist, we judge the potential for lateral spreading to occur at the site to be low to moderateand do not recommend remedial measures.

6.2.5 Seismically-Induced SubsidenceSeismically-induced ground shaking can cause vertical subsidence of specific types of soils.

Seismically related settlement generally results from the densification of loose sands and sandy

silts due to vibrations or liquefaction. The borings encountered clayey sand with gravel and silty

sand with gravel which was generally medium dense in the upper 10 to 15 feet and dense below

that depth. At boring B-3, some loose silty sand was encountered. Based upon the materials

encountered in our exploratory borings, the potential for significant seismically-inducedsubsidence is low to moderate. As a result of the type of improvements proposed (multi-use

pathway, etc.), no remedial measures are recommended.

6.2.6 Ground LurchingGround lurching is a phenomenon whereby strong seismic shaking causes cracking and

deformation of the ground surface in areas underlain by soft weak soils. The cracking and

deformation are the result of the disruption of the passing earthquake waves. Based on the


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known site soil conditions and our analysis, there is a low potential for ground lurching at the site

and no remedial measures are recommended.


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7.0 ENGINEERING ANALYSES7.1 STABILITY ANALYSES7.1.1 Analysis MethodsStatic and pseudostatic stability of representative cross sections of the retaining

wall/embankment were evaluated using limit equilibrium slope stability methods. Pseudostatic

stability analyses were performed using a pseudostatic coefficient determined according to the

methods described in 2008 California Geologic Survey document SP117A titled, Guidelines

for Evaluating and Mitigating Seismic Hazards in California. The mean moment magnitude

used in the pseudostatic stability analyses was determined from a probabilistic seismic hazard

deaggregation analysis tool on the United States Geological Survey (USGS) website. All

analyses were performed using the computer program GSLOPE (v. 5.03). The following

wall/embankment configurations were analyzed:

Sta 117+00: this existing steep section was used to back-calculate a reasonable cohesionvalue for other analyses (see Section 7.1.2.);

Sta 115+50: this section consists of a 12 ft tall segmental retaining wall supported by a cast-in-drilled hole pile foundation. The stability model used a 250 psf live load surcharge for

Stanley Boulevard and a 125 psf surcharge for the pathway. This section requires piles due

to the steepness of the slope below the retaining walls.

Sta 104+00: this section consists of a 12 ft tall segmental retaining wall founded on aleveling pad. The stability model used a 250 psf live load surcharge for Stanley Boulevardand a 125 psf surcharge for the pathway. This section is flatter and does not require a pile

foundation.

Sta 101+50: this section consists of a 12 ft tall segmental retaining wall founded on aleveling pad. The stability model used a 250 psf live load surcharge for Stanley Boulevard

and a 125 psf surcharge for the pathway. This section is similar to Sta 104 +00, but with a

slightly different geometry.

The analyses were completed using Bishops Modified Method of analysis and search routines

were used to evaluate a large number of failure surfaces and identify the most critical surface fora given slope. Only circular potential failure surfaces were considered.

7.1.2 Material Properties Assumed for Stability AnalysisIn situ unit weight was evaluated based on the test data summarized on the boring logs. Based

on these data, an average unit weight of 128 pcf was judged to be representative of the upper

portion of the embankment and the compacted retaining wall backfill materials consisting of silty


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sand (SM) with gravel, which will be generated from the project excavations. For the existing

materials below the proposed improvements, consisting of clayey sand (SC) with gravel, an

average unit weight of 130 pcf was assumed.

Shear strength properties were initially determined for the embankments materials based on the

blow counts recorded during the subsurface investigation and published correlations. However,

stability analyses of the existing conditions at the site indicate that these are too low, as use of

the friction angles from the correlations would indicate that the existing embankment would have

already failed while long term performance of the cut shows otherwise. We addressed this by

performing a parametric back-calculation of the cohesion values necessary to arrive at factors of

safety of 1.0, 1.1, and 1.2 for the steepest area of the existing slope (Sta 117+00). The resulting

calculated cohesion values needed to attain these factors of safety are shown in Table 2.

Table 2. Back Calculated Soil Cohesion for Various Factors of Safety

MaterialUnit Weight

(lb/ft3)

Friction Angle

(degrees)

Cohesion

Factor of Safety

1.0 1.1 1.2

Silty Sand (SM)

with Gravel128 32 80 psf 103 psf 125 psf

Clayey Sand (SC)

with Gravel130 36 150 psf 195 psf 245 psf

For the analyses of sections with proposed improvements, we used the lowest back-calculated

cohesion value (Station 117+00, Factor of Safety =1.0). In our opinion, this value is

conservative since the finished quarry excavation was likely intended to have a minimum factor

of safety on the order of 1.2 to 1.3. The long-term performance of the cut also suggests that the

factor of safety is well above unity. If the factor of safety was much lower than 1.2, we would

generally expect to see poor long-term performance exhibited as tension cracks, settlement,

general deformation, localized failures, etc.

7.1.3 Groundwater Conditions Assumed for Stability AnalysisGroundwater conditions assumed for within the embankments were based on the subsurface

investigation which did not encounter an elevated ground water condition and supported theground water being at the elevation of the Shadow Cliffs Lake. Since the depth to groundwater

was on the order of 50 feet, it was not modeled in the stability analyses performed for the

proposed improvements.


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7.1.4 Results of Stability AnalysisThe results of analysis indicate static factors of safety for the planned configurations are in

excess of 1.5 and pseudostatic (seismic) factors of safety are in excess of 1.0 as required by the

SP117A screening procedure. As a result of passing the seismic screening procedure, seismic

displacement analyses were not performed. The GSLOPE computer output is included in

Appendix D.


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8.0 DESIGN AND CONSTRUCTION RECOMMENDATIONS8.1 DESIGN RECOMMENDATIONSIn order to provide a level subgrade on which to construct the proposed roadway widening and

multi-use pathway, a retaining wall will need to be constructed along the portion of the project

that runs along the crest of the cut slope on the north side of Shadow Cliffs Lake. Evaluation of

the relative costs, constructability, and aesthetics of different potential retaining wall systems

was completed and discussed with County personnel. Conventional and pile supported

segmental retaining walls were determined to be the preferred retaining wall system for the

majority of the site. For areas where the geogrid reinforced zone cannot be accommodated, a

conventional reinforced concrete retaining wall should be used. Recommendations for each of

these two types of retaining wall systems are provided below.

8.1.1 Segmental Retaining Wall (SRW)Segmental retaining walls should be designed in conformance with the provisions of the

Geotechnical Engineering Circular No. 11 - Design and Construction of Mechanically

Stabilized Earth Walls and Reinforced Soil Slopes, published by the United States Department

of Transportation Federal Highway Administration, publication number FHWA-NHI-10-024.

8.1.1.1 Wall UnitsSegmental retaining wall units should be masonry units manufactured in accordance with ASTMC90 and ASTM C140. SRW unit concrete should have a minimum 28 day compressive strength

of 3,000 psi and should have a maximum moisture absorption of 6 percent to 8 percent. The

nominal dimensions of the retaining wall units should be 8 inches high, 18 inches wide, and 20

inches deep.

8.1.1.2 SoilsSegmental retaining wall design relies upon the unit weight, internal friction angle, and cohesion

parameters of the backfill soil, the soil to be retained, and the foundation soil underlying the

wall. Based on the normalized standard penetration test (SPT) blow count values and acorrelation published by Terzaghi, Peck, and Mesri (Terzaghi, 1996), the recommended

parameters to design mechanically stabilized earth (MSE) retaining walls are shown below in

Table 3. The values shown for retained zone and foundation zone soils represent the in situ

conditions judged to exist at the site and are the same (sans cohesion) as those used in the global

stability analyses discussed in Section 7. The values shown for the reinforced zone are

representative of the expected strength of the compacted on site soils and the minimum strength

required of any potential import materials.


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Table 3. MSE Retaining Wall Design Soil Parameters

Portion of

Retaining Wall

Unit Weight

(lb/ft3)

Friction Angle

(degrees)

Cohesion*

(lb/ft2)

Reinforced Zone 130 32 0Retained Zone 128 32 0

Foundation Zone 130 36 0

* For SRW wall analyses cohesion is ignored in accordance with Geotechnical Engineering

Circular No. 11 - Design and Construction of Mechanically Stabilized Earth Walls and

Reinforced Soil Slopes

Backfill soil for use in the reinforced zone (between the geogrid layers) should have a plasticity

index of less than 12 percent, a liquid limit less than 40 percent, and an effective angle of internal

friction of no less than 32 degrees. Backfill soil should not contain organic material (top soil)and should not be placed in loose lifts exceeding 8 inches. These requirements apply to both on

site materials and potential import materials to be used in the reinforced zone.

8.1.1.3 Geogrid ReinforcementThe minimum geogrid length should be at least 8 feet or 70 percent of the design height of the

wall, whichever is greater. The long-term design strength (LTDS), vertical spacing, and lengths

should be determined based on design analyses in accordance with Geotechnical Engineering

Circular No. 11. Geogrid strengths, spacing, and lengths may also need to be modified based on

global stability analyses.

8.1.1.4 FoundationThe SRW should be supported on a foundation consisting of either a conventional SRW leveling

pad or cast-in-drilled-hole (CIDH) concrete pile foundation. The need for a leveling pad or a

pile supported foundation should be determined based on the results of site specific geometry

and the global stability analyses discussed in Section 7.

Conventional SRW Leveling Pad

A conventional SRW leveling pad foundation should be used along the retaining wall alignmentwhere there is a minimum of 10 feet to daylight (soil between the face of the lower most wall

unit and a 2H:1V plane buried completely below the existing embankment). For walls that have

design heights less than 10 feet tall, the daylight value may be reduced to the design height or 4

feet, whichever is less.


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The top of the leveling pad should be embedded below the finish ground in front of the wall a

minimum of 15 percent of the wall height. The wall height is taken as the distance from the top

of the uppermost wall unit to the bottom of the lowermost wall unit.

The leveling pad should be 30 inches wide and consist of Caltrans Class 2 aggregate base

compacted to a minimum of 95 percent relative compaction (Caltrans Test 216). The units

should be centered on the leveling pad. The leveling pad elevation should be determined based

on the embedment criteria above.

Pile Supported Foundation

A CIDH concrete pile and pile cap foundation should generally be used where the slopes in front

of the wall are too steep and the daylight requirement above cannot be met. The extent of the

pile supported foundation should be determined based on global stability analyses.

The cast-in-drilled-hole pile foundations should be designed to resist all vertical and lateral

loads. Allowable active pressures and passive resistances that can be used to design the piles are

presented in Table 4. The loading is also shown on Figure 7.

Table 4. Pile and Pile Cap Design Parameters

Condition in

Front of Wall

Active pressure

(Level Backfill at Top of Wall)

Passive

Resistance

Level Slope* 45 psf/ft 400 psf/ft

2H:1V Slope 45 psf/ft 160 psf/ft

*or 10 feet below top of grade beam for passive resistance.

The active pressure should be applied to the projected area of the grade beam and CIDH piles to

a depth of 4 feet below the top of the grade beam.

The passive pressure should be neglected to a depth of 4 feet below the top of the grade beam.

Additional geotechnical design parameters that should be used in design of the CIDH piles are

presented in Table 5.


24/81

14 May 2010 Page 20



Table 5. CIDH Pile Design Parameters

Parameter Value

Minimum Diameter 24 inches

Allowable Skin Friction 250 psfMinimum Spacing Three (3) pile diameters

Minimum Depth 15 feet below bottom of pile cap

8.1.1.5 Wall DrainageTo reduce the potential for the build-up of hydrostatic pressures, the retaining wall should

include a permanent drainage system. The SRW drainage system should consist of crushed

aggregate zone that is 12 inches wide and extends from the top of the leveling pad to a depth of 2

feet below the top of wall elevation and a perforated subdrain pipe. The crushed aggregate

should be either Caltrans Class 2 permeable material or free draining crushed rock or coarsegravel, 3/8 inch to 3/4 inch, with no more than 5 percent passing the no. 200 sieve. The crushed

rock or coarse gravel should be encapsulated by filter fabric. The retaining wall unit voids, if

any, should also be infilled with the crushed aggregate (unit/drain fill). All crushed rock

drainage materials should be compacted by vibratory compaction to either 90 percent relative

compaction in accordance with Caltrans California Test 216 (for Class 2 permeable material) or

until the drain rock is in a dense tight condition (free draining crushed rock).

Perforated subdrain pipes should be installed with the holes down located. The flow line of the

perforated pipe should be located approximately 2 inches above the bottom of the drain rock

material. Cleanouts consisting of non-perforated tightline pipe located in utility boxes should beprovided at the high end(s), and every 100 feet. The perforated subdrain pipe should be

connected to a tightline discharge pipe that outlets at the slope face and is protected by a

corrugated metal pipe sleeve. Discharge pipes should be provided every 50 feet along the length

of all drains.

Rock slope protection consisting of Caltrans Facing Class rock slope protection should be

provided at the discharge pipe outlet location to reduce the potential of soil erosion during

normal wall drainage and when flushing the system during periodic maintenance. The cleanout

system should be tested prior to backfilling over the drain material.

Filter fabric shall be Caltrans Underdrain Filter Fabric with a minimum weight of 6 ounces per

square yard.

Drain pipes should be SDR 35 polyvinyl chloride (PVC).


25/81

14 May 2010 Page 21



8.1.2 Concrete and Masonry Retaining WallsConcrete and masonry retaining walls may be utilized for the project and can be founded on

either a spread footing or piles based upon the site conditions. For concrete and masonry walls,

the embedment and drainage recommendations presented above apply.

Concrete retaining walls should be designed to be supported on either a spread footing and/or a

CIDH pile foundation based on the criteria presented above for the segmental retaining wall.

Concrete retaining walls should be utilized to support the overlook structure and an electrical

utility vault located near the overlook structure. Concrete walls could potentially also be used at

any of the locations where retaining walls are proposed and could be up to about 12 feet tall.

8.1.2.1 Design LoadsActive pressures and passive resistances for design of the retaining walls were developed usingCoulomb lateral earth pressure theory based on a soil having an internal friction angle of 32

degrees. A loading diagram for the walls is shown on Figure 7 and is summarized in Table 6.

Table 6. Concrete and Masonry Retaining Wall Design Parameters

Parameter Value

Active Equivalent Fluid Pressure 45 psf/ft

Minimum Embedment 2 feet*

Minimum Width 3 feet

Allowable Bearing Capacity 2,500 psf

Coefficient of Friction 0.35

Passive Equivalent Fluid Pressure

for footing design

0 psf/ft

Passive Equivalent Fluid Pressure

for CIDH Pile design

160 psf/ft

* the 2 feet embedment depth is only applicable if greater depth is not required to comply with

the 10 feet to daylight recommendation.

When combining friction and passive pressure in the footing design, one of the two should be

reduced by 50 percent.

The bearing value indicated above is for the total of dead and frequently applied live loads and

may be increased by one third for short duration loading, which includes the effects of wind or

seismic forces. For the purpose of bearing calculations, the weight of the concrete in the footing

may be neglected.


26/81

14 May 2010 Page 22



The actual dimensions and reinforcement for the footing should be determined by structural

design calculations. The vertical load capacity of the CIDH piles and the minimum requirement

of the piles are contained in Table 5.

8.2 CONSTRUCTION RECOMMENDATIONS8.2.1 PilesPile construction should conform to the provisions of Section 49, Piling, of the State of

California Department of Transportation (Caltrans) Standard Specifications, May 2006 edition,

except as modified herein. The bottoms of the drilled holes should be dry and free of loose

cuttings and debris prior to the installation of reinforcing steel and concrete. This should be done

to the satisfaction of an engineer or geologist from CE&G. Dobie blocks or similar devices

should be used to centralize the reinforcing steel in the hole. The reinforcing steel should also besupported at the ground surface such that it hangs a minimum of 4 inches above the bottom of

the hole. The concrete should be placed neatly in the holes. Sono tubes or similar forming

materials should used, if necessary.

Although water was not encountered above a depth of 50 feet and likely be below the depth of

the proposed improvements, it is possible that adverse groundwater conditions may be

encountered during construction. The contractor should be prepared to drill and place the steel

and concrete for the foundation piers on the same day should adverse groundwater condition be

encountered during construction. Under no circumstances should water be allowed to remain in

a drilled pier hole overnight. Should this occur, it may be necessary for the contractor to enlargethe hole to a wider diameter and/or a greater depth as deemed necessary by an engineer or

geologist from our office.

It should also be noted that although caving was not encountered in the borings, the potential to

encounter running sands/silts that would necessitate casing of portions of the drilled holes may

exist. The contractor should be prepared for this potential situation.

8.2.2 Structure ExcavationsExcavation for construction of improvements will include but not be limited to excavations for

retaining walls, pipes, grade beam, spread footing, and possibly for temporary access. All

excavations should be cleaned of all loose material, moistened, and free of shrinkage cracks prior

to placing concrete and concrete pipe. This should be done to the satisfaction of an engineer or

geologist from Cal Engineering & Geology.


27/81

14 May 2010 Page 23



8.2.3 EarthworkIt is anticipated that embankment fills will be required to arrive at the final grades and for the

backfilling of excavations which include but are not limited to retaining walls, utility

excavations, pipes, and footings. All fill placed at the site should be engineered and compacted

to the following specifications.

8.2.3.1 Fill placementPrior to commencement of earthwork operations, the area to receive fill should be cleared and

grubbed of existing vegetation. All existing structures and debris should be removed from the

site, including but not limited to: pavement, concrete, buried pipes, etc. Prior to placement of

engineered fill, all loose soil and vegetation should be removed from the areas to receive fill. All

depressions created by the tree removal and demolition of existing structures should be

excavated to firm soil prior to placement of fill.

Backfill within the reinforced zone of the SRW should be placed from the wall rearward into the

embankment to create tautness in the geogrid. Backfill should be placed, spread, and compacted

in such a manner that minimizes the development of slack or loss of pre-tension of the geogrid. .

Only hand-operated compaction equipment should be allowed within 3 feet of the back surface

of the retaining wall units or the construction surface slope crest. Tracked construction

equipment shall not be operated directly on the geogrid. A minimum uncompacted backfill

thickness of 6 inches is required prior to operation of tracked vehicles over the geogrid. Turning

of tracked vehicles should be kept to a minimum to reduce the potential for tracks displacing the

fill and damaging the geogrid. Rubber-tired equipment may pass over the geogrid reinforcement

at slow speeds, less than 10 mph. Sudden braking and sharp turning should be prevented.

All fill should be placed as engineered fill and compacted to a minimum relative compaction of

90 percent (or greater) as determined by the Caltrans California Test 216 procedure at a moisture

content of 1 to 3 percent above optimum. Fill materials should be spread evenly and compacted

in uniform lifts not exceeding 8 inches in uncompacted thickness. Fill materials which do not

meet the specified relative compaction should be ripped, moisture conditioned, and re-compacted

until the required relative compaction and moisture content are attained.

All imported fill must be reviewed and approved by the geotechnical engineer prior to

importation to the site. A minimum of three to four days will be required to evaluate and test the

suitability of all proposed imported materials. All imported materials should conform to the

provisions of Section 19-4, Structure Backfill, of the Caltrans Standard Specifications, and

the Section 8.1.1.2.


28/81

14 May 2010 Page 24



8.2.3.2 Corrosion potentialThe corrosion potential of the fill and/or native soils at finished grade should be tested to

determine if special design considerations, such as sulphate resistant concrete, are required for

the foundation systems and flatwork.

Evaluation and testing of the corrosion potential of the site soil materials is beyond the scope of

this project. Testing of this nature is generally performed after the final site grading for the

project has been completed and the desired grades have been established. The testing of the

corrosion potential of the soils at the site is used as the basis for developing concrete design

parameters for the foundation systems. Alternatively, Type V concrete may be used.

8.2.4 SRW Wall ConstructionConstruction of the SRW retaining wall should be completed in conformance with the guidelinesin Geotechnical Engineering Circular No. 11.


29/81

14 May 2010 Page 25



9.0 LIMITATIONSThe conclusions and recommendations presented in this report are based on the information

provided regarding the proposed construction, and the results of the subsurface exploration and

testing, combined with interpolation of the subsurface conditions between boring locations. This

information notwithstanding, the nature and extent of subsurface variations between borings may

not become evident until construction. If variations are encountered during construction, Cal

Engineering & Geology, Inc. should be notified promptly so that conditions can be reviewed and

recommendations reconsidered, as appropriate.

This report was prepared based on preliminary design information which is subject to change

during the design process. If the project changes, Cal Engineering & Geology, Inc. should

review both the changes and the design assumptions made in this report and prepare addenda or

memoranda as appropriate. Any modifications included in these addenda or memoranda should

be carefully reviewed by the project designers to make sure that any conclusions or

recommendations that are modified are accounted for in the final design of the project.

This report presents the results of a geotechnical and geologic investigation only and should not

be construed as an environmental audit or study. The conclusions and recommendations

contained in this report are valid only for the project described in this report. We have employed

accepted geotechnical engineering procedures, and our professional opinions and conclusions are

made in accordance with generally accepted geotechnical engineering principles and practices.

This standard is in lieu of all other warranties, either expressed or implied.


30/81

14 May 2010 Page 26



10.0 REFERENCESAlameda County Waste Management Authority and Alameda County Source Reduction and

Recycling Board, 2010, Bay-Friendly Landscape Site Analysis,

http://stopwaste.org/docs/bay-friendly_site_analysis.doc

Baily, Edgar H., 1966, Geology of Northern California, Bulletin 190, California Divisions of

Mines and Geology, Chapter 6

Cal Engineering & Geology, 1998,Design Recommendations, Stanley Boulevard Storm

Damage Repairs, project number 985440.

California Department of Conservation Division of Mines and Geology, 1982, State of California

Special Studies Zones map of the Livermore Quadrangle.

California Department of Conservation Division of Mines and Geology, 1998, Maps of Known

Active Faults Near-Source Zones in California and Adjacent Portions of Nevada,

International Conference of Building Officials, Map Scale 1.2 inches = 5 km.

Crane, R. C., 1995, Preliminary geologic map of the Livermore Quadrangle Alameda and Contra

Costa Counties, unpublished geologic map, map scale 1:24:000.

Department of Conservation, California Geologic Survey, 2008, Seismic Hazard Zones Report

for the Livermore 7.5-Minute Quadrangle, Alameda County, California (Seismic HazardZone Report 114)

Dibblee, T. W. Jr., 1980, Preliminary geologic map of the Livermore Quadrangle, Alameda and

Contra Costa Counties: U.S. Geological Survey Open File Report 80-533B map scale

1:24,000.

Harden, Geborah R., 1997, California Geology, Chapter 12

Helley, E.J., and Graymer, R.W., 1997, Quaternary geology of Alameda County, and parts of

Contra Costa, Santa Clara, San Mateo, San Francisco, Stanislaus, and San Joaquin

Counties, California: A digital database: U.S. Geological Survey Open-File Report 97-97.

Natural Resources Conservation Service, 2009, Web Soil Survey URL:

http://websoilsurvey.nrcs. usda.gov, Coordinate System: UTM Zone 10N NAD83.

Nilsen, T. H., 1975, Preliminary photointerpretation map of landslide and other surficial deposits

of the Livermore 7.5' Quadrangle Alameda and Contra Costa Counties, California: U.S.

Geological Survey Open File Map 75-277-26, map scale 1:24,000.


31/81

14 May 2010 Page 27



Terzaghi, K., Peck, R. B., and Mesri, G., 1996, Soil Mechanics in Engineering Practice, John

Wiley and Sons, New York, N.Y.

United States Department of Agriculture, National Resource Conservation Services, Soil Survey

for Alameda County western part website accessed July 2009 at

http://websoilsurvey.nrcs.usda.gov/app/.

United States Department of Transportation, 2009, Geotechnical Engineering Circular No. 11 -

Design and Construction of Mechanically Stabilized Earth Walls and Reinforced Soil

Slopes, Federal Highway Administration, FHWA-NHI-10-24.

United States Geologic Survey, 2003, Earthquake Probabilities in the San Francisco Bay region:

2002 to 2030-A Survey of Findings, Open-File Report 03-214.


32/81

ACPWA - STANLEY BOULEVARDSAFETY & STREETSCAPE IMPROVEMENT PROJECT

BETWEEN CITY LIMITS OF PLEASANTON & LIVERMORE, CA

SITE LOCATION

JOB NO. 090250 JUNE 2010 FIGURE 1

SITE LOCATION

NO SCALE FROM THOMAS BROTHER


33/81


34/81



SITE GEOLOGY


SITE LOCATION

NO SCALE FROM DIBLEE (1980


35/81



SURFICIAL SOILS


ArroyodelValle

StanleyBlvd

BadgerDr LibertyDr

StanleyBlvd

Gp

W

Gp

Gp

YmA

W

YmA

WYmA

601600

601600

601800

601800

602000

602000

602200

602200

602400

602400

602600

602600

602800

602800

603000

603000

603200

603200

0 1,000 2,000 3,000500Feet

0 200 400 600100Meters

Map Scale: 1:9,200 if printed on A size (8.5" x 11") sheet.

ITE CATIN

M NC EB I E (2008

$ODPHGD$UHD&DOLIRUQLD&$

0DS8QLW6\PERO 0DS8QLW1DPH $FUHVLQ$2, 3HUFHQWRI$2,

*S *UDYHOSLW

: :DWHU


36/81



SEISMIC HAZARDS


SITE LOCATION

FROM CALIFORNIA GEOLOGIC SURVEY SEISMIC HAZARD ZONE MAP (2008


37/81


38/81


39/81


APPENDIX A

BORING LOGS


40/81

Coarse-GrainedSoils

Morethan50%

ofmaterialis

retainedontheNo.

200sie

ve.

CLASSIFICATIONOFGRAVELS&S

ANDSWITH

5%TO12%FINESREQUIRESDUA

LSYMBOLS

GW/GMorGP/GM:

Gravel/SiltyGravel

GW/GCorGP/GC:

Gravel/ClayeyGravel

SW/SMorSP/SM:

Sand/Silt

ySand

SW/SCorSP/SC:

Sand/Cla

yeySand

Fine-GrainedSoils

Morethan50%

ofmaterial

passestheNo.

200sieve.

60

50

CH or OH40

30

CL or OL20

MH or OH

10

CL-ML ML or OL

0

0 10 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT (LL)

PLASTICITYINDEX(PI)

UNIFIED SOIL CLASSIFICATION SYSTEMAND KEY TO BORING LOG

UNIFIED SOIL CLASSIFICATION SYSTEM (ASTM D-2487)

Field IdentificationGroup

Symbols Typical Names Laboratory Classification Criteria

Gravels

More than 50%

coarse fraction

retained on the

No. 4 sieve

CleanGravels

< 5% Fines

GWWell-graded gravels, gravel-sand

mixtures, little or no finesCU = D60 D10$ 4 and

CC = (D30)2 (D10 D60) $ 1 & # 3

GPPoorly graded gravels, gravel-sand mixtures, little or no fines

CU = D60 D10 < 4 and/orCC = (D30)

2 (D10 D60) < 1 & > 3

Gravelswith

Fines

>12% Fines

GM Silty gravels, poorly gradedgravel-sand-silt mixturesFines classify as

ML orMHIf fines classify as

CL-ML, use dual

symbol GC/GMGCClayey gravels, poorly graded

gravel-sand-clay mixtures

Fines classify as

CL orCH

Sands

More than 50%

coarse fraction

passes the

No. 4 sieve

CleanSands

< 5% Fines

SWWell-graded sands, gravelly

sands, little or no finesCU = D60 D10$ 6 and

CC = (D30)2 (D10 D60) $ 1 & # 3

SPPoorly graded sands, gravelly

sands, little or no finesCU = D60 D10 < 6 and/or

CC = (D30)2 (D10 D60) < 1 & > 3

Sandswith

Fines

>12% Fines

SMSilty sands, poorly graded

sand-silt mixtures

Fines classify as

ML orMHIf fines classify as

CL-ML, use dual

symbol SC/SMSCClayey sands, poorly graded

sand-clay mixtures

Fines classify as

CL orCH

Identification Procedures on Percentage Passing the No. 40 Sieve PLASTICITY CHARTFor Classification of Fine-Grained Soils and

Fine-Grained Fraction of Coarse-Grained SoilsEquation of "A"-Line: PI = 4 @ LL = 4 to 25.5, then PI = 0.73 (LL ! 20)Equation of "U"-Line: LL = 16 @ PI = 0 to 7, then PI = 0.9 (LL ! 8)

Silts & Clays

Liquid Limit less

than 50%

ML Inorganic silts, very fine sands,rock flour, silty or clayey finesands with slight plasticity

CLInorganic clays of low to med-ium plasticity, gravelly, sandy,and/or silty clays, lean clays

OLOrganic silts, organic silty

clays of low plasticity

Silts & Clays

Liquid Limit greater

than 50%

MHInorganic silts, micaceous ordiatomaceous fine sandy/-

silty soil, elastic silts

CHInorganic clays of high

plasticity, fat clays

OHOrganic clays of medium to

high plasticity

HIGHLY ORGANIC SOILS PTPeat and other highly

organic soils

KEY TO SAMPLER TYPES AND OTHER LOG SYMBOLSCS California Standard Sampler Depth at which Groundwater was Encountered During Drilling

CM California Modified Sampler Depth at which Groundwater was Measured After Drilling

SPT Standard Penetration Test Sampler PP Pocket Penetrometer Test

SHL Shelby Tube Sampler PTV Pocket Torvane Test

BU Bulk Sample !#200 % of Material Passing the No. 200 Sieve Test (ASTM D-1140)LL Liquid Limit of Sample (ASTM D-4318) PSA Particle-Size Analysis (ASTM D-422 & D-1140)

PI Plasticity Index of Sample (ASTM D-4318) C Consolidation Test (ASTM D-2435)

QU Unconfined Compression Test (ASTM D-2166) TXUU Unconsolidated Undrained Compression Test (ASTM D-2850)

KEY TO SAMPLE INTERVALS

Length of Sampler Interval with a CS Sampler Bulk Sample Recovered for Interval Shown (i.e., cuttings)

Length of Sampler Interval with a CM Sampler Length of Coring Run with Core Barrel Type Sampler

Length of Sampler Interval with a SPT Sampler No Sample Recovered for Interval Shown

Length of Sampler Interval with a SHL Sampler

FIGURE A-1


41/81

SILTY SAND (SM), brown, moist, medium dense, with gravel

subrounded to 1/4"


subrounded to 1"

5

7

10

7

9

11 3.7 120.6

EXPLORATORY BORING LOG

ACPWA-STANLEY BLVD. STREETSCAPESTANLEY BLVD., PLEASANTON, CA

090250 B-1

LOGGED BY: T. KEEFER

A-2

DRILL RIG: CME 75

BORING TYPE: 6" HOLLOW STEM AUGER

SURFACE ELEVATION: N/A

HAMMER WT./DROP: 140#/30" DATE DRILLED: 5/6/09

DESCRIPTION AND CLASSIFICATION

DESCRIPTION AND REMARKSSOIL

TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS

CHECKED BY: CH BORING NO.: FIGURE:

0

2

4

6

8

10

12

14


42/81

SILTY SAND (SM), brown, moist, dense, with gravel subrounded

to 1"4

17

32



090250 B-1


A-3

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


14

16

18

20

22

24

26

28


43/81

SILTY SAND (SM), brown, moist, dense, with gravel sub-rounded

SILTY SAND (SM), to CLAYEY SAND (SC), brown, moist, dense,

with gravel subrounded to 1"

5

32

20 5.2 124.7

14

15

21



090250 B-1


A-4

DRILL RIG: CME 75

BORING TYPE: 6"HOLLOW STEM AUGER





TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


28

30

32

34

36

38

40

42


44/81

Groundwater encountered at 49.5 feet.

SILTY SAND (SM) to CLAYEY SAND (SC), brown to light brown,

wet, very dense with gravel to 1"9

21

50-2"



090250 B-1


A-5

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


42

44

46

48

50

52

54

56


45/81

Auger clogged with 5 feet of material. Sample not possible.

Boring terminated at a depth of 60 feet. Boring backfilled with

Portland cement grout.



090250 B-1


A-6

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


56

58

60

62

64

66

68

70


46/81

Failed sample - In bag

SILTY SAND (SM), gray to dark brown, moist, medium dense,

with gravel subrounded to 1/2"

SILTY SAND (SM), light gray, moist, medium dense, with gravel

subrounded to 1"


subrounded to 1"

Failed recovery

12

15

66

12

11

11

8

12

13 4.6 118.5

7

6

7



090250 B-2


A-7

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS

CHECKED BY: CH BORING NO.: FIGUR:

0

2

4

6

8

10

12

14


47/81

SILTY SAND (SM), brown, moist, dense, with gravel subrounded7

19

20



090250 B-2


A-8

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


14

16

18

20

22

24

26

28


48/81

SILTY SAND (SM), brown to light brown, dense, with gravel to

1/2"

SILTY SAND (SM) to CLAYEY SAND (SC), light brown to gray,

moist, very dense, with gravel subrounded to 1"

50-6"

20

27

27



090250 B-2


A-9

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


28

30

32

34

36

38

40

42


49/81

Groundwater encountered at 49.5 feet.

SILTY SAND (SM), light brown, wet, very dense, with gravel

subrounded to 1"19

25

27



090250 B-2


A-10

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


42

44

46

48

50

52

54

56


50/81

SILTY SAND (SM) to CLAYEY SAND (SC), wet, very dense, with

gravel subrounded to 1"

Boring terminated at a depth of 61.5 feet. Boring backfilled with


15

23

27



090250 B-2


A-11

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


56

58

60

62

64

66

68

70


51/81

SILTY SAND (SM), moist, loose, with gravel subrounded to 1/2"

No recovery

SPT follow up. No blow counts, same depth

SILTY SAND (SM), brown to gray, moist, with gravel subrounded

to 1/2"

3

5

8

6

5

8



090250 B-3


A-12

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


0

2

4

6

8

10

12

14


52/81

SILTY SAND (SM) to CLAYEY SAND (SC), brown, moist, dense,

with gravel subrounded to 1"

8

17

15



090250 B-3


A-13

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


14

16

18

20

22

24

26

28


53/81

SILTY SAND (SM), grayish brown, moist, dense, with gravel

subrounded to 1"

SILTY SAND (SM), brown, moist, dense, with gravel subrounded

to 3/4"

14

22

24

23

23

16



090250 B-3


A-14

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


28

30

32

34

36

38

40

42


54/81

SILTY CLAYEY SAND (SC), wet, dense, with gravel subrounded

to 1/2" with 1" cobble

Groundwater encountered at 50 feet. 26

25

22



090250 B-3


A-15

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


42

44

46

48

50

52

54

56


55/81

SILTY SAND (SM) TO CLAYEY SAND (SC), light brown, wet,

dense, with gravel subrounded to 1/2"

Boring terminated at a depth of 61.5 feet. Boring backfilled with


12

32 10.5 132.7

33



090250 B-3


A-15

DRILL RIG: CME 75






TYPE

DEPTH

SAMPLER

(FEET)

PENETRATION

RESISTANCE

(BLOWS/6")

WATER

CONTENT(%)

DRYDENSITY

(PCF)

ATTERBERG

LIMITS

TEST

.

OTHER

TESTS


56

58

60

62

64

66

68

70


56/81


APPENDIX B

PERCOLATION TEST DATA


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Project:Stanley

BoulevardStreetImprovemen

ts

CE&GJN:0902

50

Test#

ST

A

Color/Texture/Location

Time

(hr:min)

Depth

(in)

ElapsedTimefrom

InitialReading

(hr:min)

Change

inDepthfrom

InitialReading

(in)

2,6&12":brownsiltyclayw/gra

vel

location:alongsouthsideofadjacentfootpath

2,6&12":darkbrownsiltysandw

/gravel&brick

2:42

10.00

location:10'northofE.O.P.(lined

culvertpresent)

4:13

8.00

1:31

2.00

7:55

4.75

5:13

5.25

2":darkgrayishbrownsandysiltw

/organics

3:14

9.50

6&12":darkbrownsiltysandw/gravel

7:34

3.00

4:20

6.50

location:11'fromcurb(pavedbik

epathpresent)

2

6":lightolivebrowngravel

0:37

9.00

12":lightolivebrownclayeysilt

2:26

7.00

1:49

2.00

location:5'northofE.O.P.

4:09

7.00

3:32

2.00

7:52

6.00

7:15

3.00

"

1

80+0

0EB

3:45

N/A

waterdrainedoutimmediatelydueto

extensivegopherholesinarea

initialfill

initialfill

initialfill

InSituPercolationTesting&SoilSampling

DateofFieldWork:11

March2010

4

140+0

0WB

2

100+0

0WB

3

110+00EB

:g

rowns

ycay

0:00

15.50

612":yellowish

brownclayeysilt

0:53

14.50

0:53

1.00

location:3'southofE.O.P.

3:54

11.50

3:54

4.00

7:39

8.00

7:39

7.50

2":brownsandyclayeysiltw/grav

el

1:17

10.50

612":brownsandyclayeysilt

3:59

8.50

2:42

2.00

location:3'southofE.O.P.

7:42

7.00

6:25

3.50

2":verydarkgrayishbrownsandy

siltw/gravel

2:17

10.00

612":verydarkgrayishbrownsan

dysilt

4:06

9.00

1:49

1.00

location:6'northofE.O.P.

7:49

6.00

5:32

4.00

2":brownclayeysandw/gravel

1:36

8.75

612":darkbrownsandyclayw/gravel

1:39

7.25

0:03

1.50

location:2.5'southofE.O.P.

1:41

6.00

0:05

2.75

1:44

5.75

0:08

3.00

1:50

4.25

0:14

4.50

4:01

0.00

2:25

8.75

initialfill

initialfill

initialfill

initialfill

200+00EB

86

170+00EB

7

180+0

0WB

+


58/81


APPENDIX C

SOIL TREATMENT AND FERTILITY ANALYSIS


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www.LmpCorp.com

Locations:

101 S. Winchester Blvd.uite G-173an Jose, CA 95128408) 727-0330

4741 E. Hunter Ave.Unit AAnaheim, CA 92807714) 282-8777

SAN JOSE OFFICEMarch 26, 2010Report 10-070-0044

CAL ENGINEERING & GEOLOGY, INC.119 Filbert StreetOakland, CA 94607

Attn: Dave Buscheck

RE: ALAMEDA COUNTY - STANLEY BLVD. IMPROVEMENT, JN: 090250

BACKGROUND

The eight samples received 3/11 represent site soils from areas that will be amended for

new landscaping. Recommendation regarding soil treatment and fertility maintenancewere to rely on an organic approach.

ANALYTICAL RESULTS

Gravel content is highly variable and quite excessive at 2, 4 and 8. These additionally showa broad distribution of coarse sand sizes and this diversity contributes to consolidation asthe various sizes intermingle and can become cemented by the silt and clay. The degree ofconcern regarding this is high at these locations and slight at 6 and 7 with no concern atthe others. Particle size classification of the smaller than 2-mm fractions are varied fromloam, sandy loam to clay loam. Half saturation percentage values reflect soil porosity andthat is downgraded by particle size diversity in those noted above and by high silt content at

5. All are every low in organic content and it will be the incorporation of organic matter thatwill help maintain more favorable structure. Based on these characteristics three categoriesof infiltration rates are estimated as follows:

0.29 inch per hour at 1, 3, 5 and 6.0.21 inch per hour at 7 (slow)0.15 inch per hour at 2, 4 and 8 (very slow)

Soil reaction at 4 is moderately alkaline and is the only area where alkalinity is higher a littlethan most plants prefer. All others fall in the generally suitable slightly acidic to slightlyalkaline range and all are favorably low in lime content. Salinity, boron and sodium are

safely low and the SAR value shows soluble sodium well balanced by calcium andmagnesium. Chloride levels are listed separately at the bottom of the second data sheet.All are very comfortably low except there is slight accumulation at 8. Since this and itshigher sodium content deviated significantly from the other sales it was retested andconfirmed original findings.


60/81

Page-2CAL ENGINEERING & GEOLOGY, INC.Report 10-070-0044

www.LmpCorp.com

Nutritional data show low nitrogen only at 1 and oddly high nitrogen at 2. Insufficient sampleremained to recheck this but based on its structure its use is not suggested anyway. Phosphorus isoddly high at 1 and well supplied in the others. Potassium is not particularly abundant but is only

deficient at 4, 7 and 8. Calcium and magnesium are variable but all are in suitable ranges except forjust fair magnesium at 4. Sulfate levels are adequate.

RECOMMENDATIONS

Based primarily of texture it is suggested that soils represented by 2, 4 and 8 not be used todevelop the plants immediate root zone. Removal and replacement or covering with other suitable

material is suggested. In case import is required, some guideline specifications are attached.

Aside from enhancing organic matter content none of these areas require any additives. Derivingthe organic from specified compost will take care of potassium nutrition and build up reserves of theother nutrients while also providing an abundant microbial population to assist in the naturalrecycling of nutrients.

To improve drainage of the root zone any undisturbed or compacted areas should first be loosenedto a 10-inch depth. The compost should then be spread at a rate of 6 cubic yards per 1000 squarefeet and thoroughly incorporated to 6-inches depth. This rate is based on an organic matter contentof 260 pounds per cubic yard of amendment and this may be adjusted depending on the organiccontent of the amendment selected. The theoretical target value average from this rate is to bring

soils to 5.7%.

To Prepare Backfill:

Excavate planting pits at least twice as wide as the diameter of the rootball. Soil immediately below the root ball should be left undisturbed to provide support but the

bottom around the sides should be cultivated to improve porosity.

The top of the rootball should be at or slightly above final grade. The top 12-inches of backfill around the sides of the rootball of trees and shrubs may consist of the

above amended soil or may be prepared as follows:

3 parts Pulverized Site Soil1 part Organic Amendment

-Backfill below 12 inches required for 24-inch box or larger material should not contain the organicamendment.

Ideally a weed and turf free zone should be maintained just beyond the diameter of the plantinghole. A 2-inch deep layer of coarse mulch can be placed around the tree or shrub but should bekept a minimum 4 inches from the trunk.


61/81

Page-3CAL ENGINEERING & GEOLOGY, INC.Report 10-070-0044

www.LmpCorp.com

Irrigation of new plantings should take into consideration the differing texture of the rootball and

surrounding soil to maintain adequate moisture in both during this critical period ofestablishment.

MAINTENANCE

Periodic replenishment with an organic nitrogen source should be sufficient at least until fal

cal engineering & geology

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