appendix f updated geotechnical investigation...(ti = 6.0) (ti = 7.0) (ti = 8.0) asphalt concrete 3...

10336 Alder Avenue Industrial Project

Appendix F

Updated Geotechnical Investigation

UPDATED GEOTECHNICALINVESTIGATION

PROPOSED ALDER LOGISTICS CENTER10336 Alder Avenue

San Bernardino County, Californiafor

Lake Creek Industrial

22885 Savi Ranch Parkway Suite E Yorba Linda California 92887voice: (714) 685-1115 fax: (714) 685-1118 www.socalgeo.com

November 15, 2018

Lake Creek Industrial17551 Norwood StreetTustin, California 92780

Attention: Mr. Michael JohnsonPrincipal

Project No.: 18G218-1

Subject: Updated Geotechnical InvestigationProposed Alder Logistics Center10336 Alder AvenueSan Bernardino County, California

Dear Mr. Johnson:

In accordance with your request, we have conducted a geotechnical investigation at the subjectsite. We are pleased to present this report summarizing the conclusions and recommendationsdeveloped from our investigation.

We sincerely appreciate the opportunity to be of service on this project. We look forward toproviding additional consulting services during the course of the project. If we may be of furtherassistance in any manner, please contact our office.

Respectfully Submitted,

SOUTHERN CALIFORNIA GEOTECHNICAL, INC.

Joseph Lozano LeonStaff Engineer

Gregory K. Mitchell, GE 2364Principal Engineer

Distribution: (1) Addressee

Proposed Alder Logistics Center – San Bernardino County, CAProject No. 18G218-1

TABLE OF CONTENTS

1.0 EXECUTIVE SUMMARY 1

2.0 SCOPE OF SERVICES 3

3.0 SITE AND PROJECT DESCRIPTION 4

3.1 Site Conditions 43.2 Proposed Development 4

4.0 SUBSURFACE EXPLORATION 6

4.1 Scope of Exploration/Sampling Methods 64.2 Geotechnical Conditions 6

5.0 LABORATORY TESTING 8

6.0 CONCLUSIONS AND RECOMMENDATIONS 10

6.1 Seismic Design Considerations 106.2 Geotechnical Design Considerations 126.3 Site Grading Recommendations 136.4 Construction Considerations 176.5 Foundation Design and Construction 176.6 Floor Slab Design and Construction 196.7 Retaining Wall Design and Construction 206.8 Pavement Design Parameters 22

7.0 GENERAL COMMENTS 24

APPENDICES

A Plate 1: Site Location MapPlate 2: Boring Location Plan

B Boring LogsC Laboratory Test ResultsD Grading Guide SpecificationsE Seismic Design Parameters


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1.0 EXECUTIVE SUMMARY

Presented below is a brief summary of the conclusions and recommendations of this investigation.Since this summary is not all inclusive, it should be read in complete context with the entirereport.

Site Preparation Demolition should include all foundations, floor slabs, septic systems, utilities and any other

subsurface improvements that will not remain in place with the new development. Debrisresultant from demolition should be disposed of off-site. Alternatively, concrete and asphaltdebris may be pulverized to a maximum 2-inch particle size, well mixed with the on-site soils,and incorporated into new structural fills or it may be crushed and made into crushedmiscellaneous base (CMB), if desired.

The site is generally underlain by undocumented artificial fill soils, extending to depths of 1½to 4½± feet. The existing fill soils possess unfavorable consolidation/collapse characteristics.In addition, the near-surface alluvium also varies in density and possesses low strengths.Based on these conditions, remedial grading is considered warranted within the proposedbuilding area in order to remove all of the undocumented fill soils in their entirety as well asa portion of the near-surface native alluvial soils, and replace these materials as compactedfill soils.

It is recommended that the proposed building pad area be overexcavated to a depth of atleast 4 feet below existing grade and to a depth of at least 4 feet below proposed pad grade.The overexcavation should also extend to a sufficient depth to remove all of the artificial fillmaterials. Overexcavation within the foundation areas is recommended to extend to a depthof at least 3 feet below proposed foundation bearing grade. The soils that will remain belowthe recommended depth of overexcavation generally possess greater relative densities andmore favorable strengths.

After overexcavation has been completed, the subgrade soils should be evaluated by thegeotechnical engineer to identify any additional soils that should be overexcavated. Theresulting subgrade should then be scarified to a depth of 12 inches, thoroughly moistureconditioned and recompacted. The previously excavated soils may then be replaced ascompacted structural fill.

The new pavement and flatwork subgrade soils are recommended to be scarified to a depthof 12± inches, thoroughly moisture conditioned and recompacted to at least 90 percent ofthe ASTM D-1557 maximum dry density.

Building Foundations Conventional shallow foundations, supported in newly placed structural fill soils. Maximum, net allowable soil bearing pressure: 2,500 lbs/ft2. Minimum reinforcement consisting of at least two (2) No. 5 rebars (1 top and 1 bottom) in

strip footings. Additional reinforcement may be necessary for structural considerations.

Building Floor Slab Conventional Slab-on-Grade, minimum 6 inches thick. Modulus of Subgrade Reaction: 150 psi/in.


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Reinforcement is not considered necessary, for geotechnical considerations. The actual floor slab reinforcement should be determined by the structural engineer, based

on the imposed slab loading.

Pavements

ASPHALT PAVEMENTS (R = 50)

Materials

Thickness (inches)

AutomobileParking and Drives

(TI = 4.0 & 5.0)

Truck Traffic

(TI = 6.0) (TI = 7.0) (TI = 8.0)

Asphalt Concrete 3 3½ 4 5

Aggregate Base 3 4 5 5

Compacted Subgrade 12 12 12 12


Materials

Thickness (inches)


(TI = 4.0 & 5.0)

Truck Traffic

(TI = 6.0) (TI = 7.0) (TI = 8.0)





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2.0 SCOPE OF SERVICES

The scope of services performed for this project was in accordance with our Proposal No. 18P444dated November 2, 2018. The scope of services included a visual site reconnaissance and thereview of the previously prepared geotechnical report to provide criteria for preparing the designof the building foundations, building floor slab, and parking lot pavements along with sitepreparation recommendations and construction considerations for the proposed development.The evaluation of the environmental aspects of this site was beyond the scope of services for thisgeotechnical investigation.


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3.0 SITE AND PROJECT DESCRIPTION

3.1 Site Conditions

The site is located on the west side of Alder Avenue, 600± feet north of Slover Avenue inBloomington, at the address of 10336 Alder Avenue in an unincorporated area within SanBernardino County, California. The site is bounded to the north by a Southern Pacific Railroadeasement, to the west by a railroad yard, to the south by a steel facility and to the east by AlderAvenue. The general location of the site is illustrated on the Site Location Map, enclosed as Plate1 in Appendix A of this report.

The subject site consists of an assemblage of five parcels which total 8.50± acres. The site iscurrently developed as the Gene Belk Fruit Packers and Briners facility. This facility includes ametal-frame building located in the northeastern corner of the site. This building is approximately10,000 square feet and is of metal-frame construction with sheet-metal siding, presumablysupported on a shallow foundation system with a concrete slab-on-grade floor. This building iscurrently being utilized for produce processing. The existing facility also includes numeroussmaller structures and brine tanks throughout the site as well as a single-story single-familyresidence of wood-frame construction presumably supported on a shallow foundation system witha concrete slab-on-grade floor. Groundcover generally consists of heavily weathered asphalticconcrete pavements with isolated areas of exposed soil and aggregate base, and Portland cementconcrete pavements surrounding the brine tanks.

It should be noted that the current owner of property has provided the approximate locations ofexisting underground improvements. The existing underground improvements include, but arenot limited to, a 10,000-gallon rain storage tank located in the southern region of the site, andtwo (2) septic systems in the western and eastern regions. The underground improvementspresumably extend to a depth of 12± feet below the existing site grades. In addition, each septicsystem includes a 40±-foot deep 4±-foot diameter seepage pit. The existing undergroundimprovements are depicted on Plate 2 in Appendix A of this report.

Topographic information was obtained from a conceptual grading plan prepared by SB&O, Inc.,the project civil engineer. Based on our review of this plan, the existing site topography generallyslopes downward to the south to southeast at a gradient of 1 to 2 percent. The elevation at thesubject site ranges from 1100± feet mean sea level (msl) at the northwest corner of the site to1088± feet msl in the southeast corner of the site. There is approximately 12 feet of elevationdifferential across on subject site.

3.2 Proposed Development

Based on a preliminary site plan prepared by Douglas Franz Architects, Inc., the site will bedeveloped with a 172,780± ft2 commercial/industrial building located in the northcentral regionof the site. The new building will include a 2,000± ft2 mezzanine. The new building will beconstructed with dock-high doors along the southern building wall. The building is expected to


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be surrounded by asphaltic concrete pavements in the parking and drive lane areas, Portlandcement concrete pavements in the loading dock areas, and concrete flatwork and landscapedplanters located throughout the site.

Detailed structural information has not been provided. It is assumed that the new building will bea single-story structure of tilt-up concrete construction. Based on the assumed construction,maximum column and wall loads are expected to be on the order of 100 kips and 4 to 7 kips perlinear foot, respectively.

No significant amounts of below grade construction, such as basements or crawl spaces, areexpected to be included in the proposed development. Based on the conceptual grading planprepared by SB&O, Inc., maximum cuts and fills of 1 to 3± feet are expected to be necessary toachieve the proposed site grades.


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4.0 SUBSURFACE EXPLORATION

4.1 Scope of Exploration/Sampling Methods

The subsurface exploration conducted for this project consisted of six (6) borings, advanced todepths of 5 to 20± feet below currently existing site grades. The borings for this project weredrilled on February 22, 2018. All of the borings were logged during drilling by a member of ourstaff.

All borings were advanced with hollow-stem augers, by a conventional truck-mounted drilling rig.Representative bulk and in-situ soil samples were taken during drilling. Relatively undisturbed in-situ samples were taken with a split barrel “California Sampler” containing a series of one inchlong, 2.416± inch diameter brass rings. This sampling method is described in ASTM Test MethodD-3550. In-situ samples were also taken using a 1.4± inch inside diameter split spoon sampler,in general accordance with ASTM D-1586. Both of these samplers are driven into the ground withsuccessive blows of a 140-pound weight falling 30 inches. The blow counts obtained during drivingare recorded for further analysis. Bulk samples were collected in plastic bags to retain their originalmoisture content. The relatively undisturbed ring samples were placed in molded plastic sleevesthat were then sealed and transported to our laboratory.

The approximate locations of the borings are indicated on the Boring Location Plan, included asPlate 2 in Appendix A of this report. The Boring Logs, which illustrate the conditions encounteredat the boring locations, as well as the results of some of the laboratory testing, are included inAppendix B.

4.2 Geotechnical Conditions

Pavements

Asphaltic concrete pavements were encountered at the ground surface at most of the boringlocations. The pavements consist of 2± inches of asphaltic concrete with no underlying layer ofaggregate base. However, Boring No B-5 was drilled in an area covered with aggregate base atthe ground surface. At this location, the aggregate base is 6 inches thick.

Artificial Fill

Artificial fill soils were encountered below the pavements and/or aggregate base at all of theboring locations. The fill soils extend to depths of 1½ to 4½± feet below the existing site grades.The fill soils generally consist of loose to medium dense silty fine sands and medium to coarsesands, with varying fine to coarse gravel content and occasional cobbles. The fill soils possess adisturbed, mottled, appearance, resulting in their classification as artificial fill.


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Alluvium

Native alluvial soils were encountered below the fill soils at all of the boring locations, extendingto the maximum depth explored of 20± feet below the existing site grades. The alluvial soilsgenerally consist of medium dense to very dense silty fine to medium sands, gravelly fine tocoarse sands, fine to coarse sandy gravel, and fine sandy silts, with occasional to extensivecobbles.

Groundwater

Free water was not encountered during the drilling of any of the borings. Based on the lack ofany water within the borings, and the moisture contents of the recovered soil samples, the staticgroundwater is considered to have existed at a depth in excess of 20± feet at the time of thesubsurface exploration.

As part of our research, we reviewed available groundwater data in order to determine the recenthigh groundwater level for the site. The primary reference used to determine the groundwaterdepths in this area is the California Department of Water Resources website,http://www.water.ca.gov/waterdatalibrary/. The nearest monitoring well (Well340661N1174301W001) is located approximately 3,000 feet west of the site. Water level readingswithin this monitoring well indicate a historic high water level of 268± feet (January 2010) belowthe existing site grades.


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5.0 LABORATORY TESTING

The soil samples recovered from the subsurface exploration were returned to our laboratory forfurther testing to determine selected physical and engineering properties of the soils. The testsare briefly discussed below. It should be noted that the test results are specific to the actualsamples tested, and variations could be expected at other locations and depths.

Classification

All recovered soil samples were classified using the Unified Soil Classification System (USCS), inaccordance with ASTM D-2488. Field identifications were then supplemented with additional visualclassifications and/or by laboratory testing. The USCS classifications are shown on the BoringLogs and are periodically referenced throughout this report.

Density and Moisture Content

The density has been determined for selected relatively undisturbed ring samples. These densitieswere determined in general accordance with the method presented in ASTM D-2937. The resultsare recorded as dry unit weight in pounds per cubic foot. The moisture contents are determinedin accordance with ASTM D-2216, and are expressed as a percentage of the dry weight. Thesetest results are presented on the Boring Logs.

Soluble Sulfates

Representative samples of the near-surface soils were submitted to a subcontracted analyticallaboratory for determination of soluble sulfate content. Soluble sulfates are naturally present insoils, and if the concentration is high enough, can result in degradation of concrete which comesinto contact with these soils. The results of the soluble sulfate testing are presented below, andare discussed further in a subsequent section of this report.

Sample Identification Soluble Sulfates (%) ACI-318 Classification

B-1 @ 0 to 5 feet 0.015 Not Applicable (S0)

B-3 @ 0 to 5 feet 0.047 Not Applicable (S0)

Consolidation

Selected soil samples have been tested to determine their consolidation potential, in accordancewith ASTM D-2435. The testing apparatus is designed to accept either natural or remoldedsamples in a one-inch high ring, approximately 2.416 inches in diameter. Each sample is thenloaded incrementally in a geometric progression and the resulting deflection is recorded atselected time intervals. Porous stones are in contact with the top and bottom of the sample topermit the addition or release of pore water. The samples are typically inundated with water atan intermediate load to determine their potential for collapse or heave. The results of theconsolidation testing are plotted on Plates C-1 through C-4 in Appendix C of this report.


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Maximum Dry Density and Optimum Moisture Content

A representative bulk sample has been tested for its maximum dry density and optimum moisturecontent. The results have been obtained using the Modified Proctor procedure, per ASTM D-1557and are presented on Plate C-5 in Appendix C of this report. This test is generally used to comparethe in-situ densities of undisturbed field samples, and for later compaction testing. Additionaltesting of other soil types or soil mixes may be necessary at a later date.


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6.0 CONCLUSIONS AND RECOMMENDATIONS

Based on the results of our review, field exploration, laboratory testing and geotechnical analysis,the proposed development is considered feasible from a geotechnical standpoint. Therecommendations contained in this report should be taken into the design, construction, andgrading considerations.

The recommendations are contingent upon all grading and foundation construction activitiesbeing monitored by the geotechnical engineer of record. The recommendations are provided withthe assumption that an adequate program of client consultation, construction monitoring, andtesting will be performed during the final design and construction phases to verify compliancewith these recommendations. Maintaining Southern California Geotechnical, Inc., (SCG) as thegeotechnical consultant from the beginning to the end of the project will provide continuity ofservices. The geotechnical engineering firm providing testing and observation services shallassume the responsibility of Geotechnical Engineer of Record.

The Grading Guide Specifications, included as Appendix D, should be considered part of thisreport, and should be incorporated into the project specifications. The contractor and/or ownerof the development should bring to the attention of the geotechnical engineer any conditions thatdiffer from those stated in this report, or which may be detrimental for the development.

6.1 Seismic Design Considerations

The subject site is located in an area which is subject to strong ground motions due toearthquakes. The performance of a site specific seismic hazards analysis was beyond the scopeof this investigation. However, numerous faults capable of producing significant ground motionsare located near the subject site. Due to economic considerations, it is not generally consideredreasonable to design a structure that is not susceptible to earthquake damage. Therefore,significant damage to structures may be unavoidable during large earthquakes. The proposedstructures should, however, be designed to resist structural collapse and thereby providereasonable protection from serious injury, catastrophic property damage and loss of life.

Faulting and Seismicity

Research of available maps indicates that the subject site is not located within an Alquist-PrioloEarthquake Fault Zone. Furthermore, SCG did not identify any evidence of faulting during thegeotechnical investigation. Therefore, the possibility of significant fault rupture on the site isconsidered to be low.

Seismic Design Parameters

Based on standards in place at the time of this report, the proposed development is expected tobe designed in accordance with the requirements of the 2016 edition of the California BuildingCode (CBC). The CBC provides procedures for earthquake resistant structural design that includeconsiderations for on-site soil conditions, occupancy, and the configuration of the structure


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including the structural system and height. The seismic design parameters presented below arebased on the soil profile and the proximity of known faults with respect to the subject site.

The 2016 CBC Seismic Design Parameters have been generated using U.S. Seismic Design Maps,a web-based software application developed by the United States Geological Survey. Thissoftware application, available at the USGS web site, calculates seismic design parameters inaccordance with the 2016 CBC, utilizing a database of deterministic site accelerations at 0.01degree intervals. The table below is a compilation of the data provided by the USGS application.A copy of the output generated from this program is included in Appendix E of this report. A copyof the Design Response Spectrum, as generated by the USGS application is also included inAppendix E. Based on this output, the following parameters may be utilized for the subject site:

2016 CBC SEISMIC DESIGN PARAMETERS

Parameter Value

Mapped Spectral Acceleration at 0.2 sec Period SS 1.500

Mapped Spectral Acceleration at 1.0 sec Period S1 0.608

Site Class --- D

Site Modified Spectral Acceleration at 0.2 sec Period SMS 1.500

Site Modified Spectral Acceleration at 1.0 sec Period SM1 0.912

Design Spectral Acceleration at 0.2 sec Period SDS 1.000

Design Spectral Acceleration at 1.0 sec Period SD1 0.608

Liquefaction

Liquefaction is the loss of the strength in generally cohesionless, saturated soils when the pore-water pressure induced in the soil by a seismic event becomes equal to or exceeds the overburdenpressure. The primary factors which influence the potential for liquefaction include groundwatertable elevation, soil type and grain size characteristics, relative density of the soil, initial confiningpressure, and intensity and duration of ground shaking. The depth within which the occurrenceof liquefaction may impact surface improvements is generally identified as the upper 50 feetbelow the existing ground surface. Liquefaction potential is greater in saturated, loose, poorlygraded fine sands with a mean (d50) grain size in the range of 0.075 to 0.2 mm (Seed and Idriss,1971). Clayey (cohesive) soils or soils which possess clay particles (d


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6.2 Geotechnical Design Considerations

General

All of the borings encountered artificial fill materials at the ground surface. The fill soils extend todepths of 1½ to 4½± feet at the borings performed within the proposed building area. Based ona lack of documentation regarding the placement and compaction of the existing fill materials,these soils are considered to consist of undocumented fill, and are not suitable for the support ofthe foundation loads of the proposed building. In addition, the near-surface alluvial soils possessvarying strengths and densities. Finally, the near-surface soils will become significantly disturbedduring demolition of the existing structures. Remedial grading is considered warranted within theproposed building area to remove the artificial fill soils in their entirety and an upper portion ofthe near-surface native alluvium, and replace these soils as compacted structural fill.

Settlement

The recommended remedial grading will remove the existing undocumented fill soils and a portionof the near-surface native alluvial soils and replace these materials as compacted structural fill.The native soils that will remain in place below the recommended depth of overexcavation willnot be subject to significant stress increases from the foundations of the new structure. Therefore,following completion of the recommended grading, post-construction settlements are expectedto be within tolerable limits.

Soluble Sulfates

The results of the soluble sulfate testing indicate soluble sulfate concentrations of 0.015 to 0.047percent within the tested soil samples. These concentrations are considered to be not applicable(S0) with respect to the American Concrete Institute (ACI) Publication 318-14 Building CodeRequirements for Structural Concrete and Commentary, Section 4.3. Therefore, specializedconcrete mix designs are not considered to be necessary, with regard to sulfate protectionpurposes. It is, however, recommended that additional soluble sulfate testing be conducted atthe completion of rough grading to verify the soluble sulfate concentrations of the soils which arepresent at pad grade within the building area.

Expansion

The near-surface soils generally consist of silty fine sands and medium to coarse sands, withvarying fine to coarse gravel content and occasional cobbles. These materials have been visuallyclassified as very low to non-expansive. Therefore, no design considerations related to expansivesoils are considered warranted for this site.

Shrinkage/Subsidence

Based on the results of the laboratory testing, removal and recompaction of the near-surface fillsoils is estimated to result in an average shrinkage of 10 to 14 percent. Removal and replacementof the near-surface native alluvium will likely result in an average shrinkage of 6 to 10 percent.However, the estimated shrinkage of the individual soil layers at the site is highly variable, locallyranging from a minimum shrinkage value of 1 percent to a maximum shrinkage of 19 percent at


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varying sample depths and locations. It should be noted that the potential shrinkage estimate isbased on dry density testing performed on small-diameter samples taken at the boring locations.If a more accurate and precise shrinkage estimate is desired, SCG can perform a shrinkage studyinvolving several excavated test-pits where in-place densities are determined using in-situ testingmethods instead of laboratory density testing on small-diameter samples. Please contact SCG fordetails and a cost estimate regarding a shrinkage study, if desired.

Minor ground subsidence is expected to occur in the soils below the zone of removal, due tosettlement and machinery working. The subsidence is estimated to be 0.1 feet.

These estimates are based on previous experience and the subsurface conditions encountered atthe boring locations. The actual amount of subsidence is expected to be variable and will bedependent on the type of machinery used, repetitions of use, and dynamic effects, all of whichare difficult to assess precisely.

Grading and Foundation Plan Review

Grading and foundation plans were not available at the time of this report. It is thereforerecommended that we be provided with copies of the preliminary grading and foundation plans,when they become available, for review with regard to the conclusions, recommendations, andassumptions contained within this report.

6.3 Site Grading Recommendations

The grading recommendations presented below are based on the subsurface conditionsencountered at the boring locations and our understanding of the proposed development. Werecommend that all grading activities be completed in accordance with the Grading GuideSpecifications included as Appendix D of this report, unless superseded by site-specificrecommendations presented below.

Site Stripping and Demolition

Demolition of the existing structures and pavements will be necessary in order to facilitate theconstruction of the proposed development. Demolition should include all foundations, floor slabs,septic systems, rainwater storage tank, utilities and any other subsurface improvements that willnot remain in place with the new development. Debris resultant from demolition should bedisposed of off-site. Alternatively, concrete and asphalt debris may be pulverized to a maximum2-inch particle size, well mixed with the on-site soils, and incorporated into new structural fills orit may be crushed and made into crushed miscellaneous base (CMB), if desired.

Demolition of the existing septic systems should include the removal of the sewer septic tanks,in their entirety, and the abandonment of the existing seepage pits. The seepage pit structuresshould be removed to a depth of at least 1 foot below the base of the recommendedoverexcavation within the proposed building pad area (as presented in the next section of thisreport) and to at least 3 feet below the proposed subgrade elevations outside the building padarea. The remaining section of the seepage pit should then be backfilled with a 2-sack cementslurry mix. The existing rainwater storage tank should be removed in its entirety.


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Initial site stripping should include removal of any surficial vegetation from the site. Strippingshould include any shrubs, trees and any organic top soils located in the landscaped planter areas.Root balls associated with the trees should be removed in their entirety, and the resultantexcavations should be backfilled with compacted structural fill soils. The actual extent of sitestripping should be determined in the field by the geotechnical engineer, based on the organiccontent and stability of the materials encountered.

Treatment of Existing Soils: Building Pad

Remedial grading should be performed within the proposed building area in order to remove theexisting undocumented fill soils, which extend to depths of 1½ to 4½± feet, at the boringlocations. The existing soils within the proposed building area are also recommended to beoverexcavated to a depth of at least 4 feet below existing grade and to a depth of at least 4 feetbelow proposed building pad subgrade elevation, whichever is greater, to provide a uniform layerof compacted fill below the new structure. The overexcavation should also extend to asufficient depth to remove the undocumented fill soils in their entirety.

Additional overexcavation should be performed within the influence zones of the new foundations,to provide for a new layer of compacted structural fill extending to a depth of 3 feet belowproposed bearing grade.

The overexcavation areas should extend at least 5 feet beyond the building and foundationperimeters, and to an extent equal to the depth of fill placed below the foundation bearing grade,whichever is greater. If the proposed structure incorporates any exterior columns (such as for acanopy or overhang) the area of overexcavation should also encompass these areas.

Following completion of the overexcavation, the subgrade soils within the building area shouldbe evaluated by the geotechnical engineer to verify their suitability to serve as the structural fillsubgrade, as well as to support the foundation loads of the new structure. This evaluation shouldinclude proofrolling and probing to identify any soft, loose or otherwise unstable soils that mustbe removed. Some localized areas of deeper excavation may be required if additionalfill materials or loose, porous, or low density native soils are encountered at the baseof the overexcavation.

After a suitable overexcavation subgrade has been achieved, the exposed soils should be scarifiedto a depth of at least 12 inches, moisture treated to 0 to 4 percent above optimum, andrecompacted to at least 90 percent of the ASTM D-1557 maximum dry density. The previouslyexcavated soils may then be replaced as compacted structural fill.

Treatment of Existing Soils: Retaining Walls and Site Walls

The existing soils within the areas of any proposed retaining walls and non-retaining site wallsshould be overexcavated to a depth of 3 feet below foundation bearing grade and replaced ascompacted structural fill as discussed above for the proposed building pad. Any undocumentedfill soils within any of these foundation areas should be removed in their entirety. Theoverexcavation areas should extend at least 5 feet beyond the foundation perimeters, and to anextent equal to the depth of fill below the new foundations. Please note that erection pads are


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considered to be part of the foundation system. The overexcavation subgrade soils should beevaluated by the geotechnical engineer prior to scarifying, moisture conditioning, andrecompacting the upper 12 inches of exposed subgrade soils. The previously excavated soils maythen be replaced as compacted structural fill.

Treatment of Existing Soils: Flatwork, Parking and Drive Areas

Based on economic considerations, overexcavation of the existing near-surface existing soils inthe new flatwork, parking and drive areas is not considered warranted, with the exception ofareas where lower strength or unstable soils are identified by the geotechnical engineer duringgrading. Subgrade preparation in the new flatwork, parking and drive areas should initially consistof removal of all soils disturbed during stripping and demolition operations.

The geotechnical engineer should then evaluate the subgrade to identify any areas of additionalunsuitable soils. Any such materials should be removed to a level of firm and unyielding soil. Theexposed subgrade soils should then be scarified to a depth of 12± inches, moisture conditionedto 0 to 4 percent above the optimum moisture content, and recompacted to at least 90 percentof the ASTM D-1557 maximum dry density. Based on the presence of variable strength surficialsoils throughout the site, it is expected that some isolated areas of additional overexcavation maybe required to remove zones of lower strength, unsuitable soils.

The grading recommendations presented above for the proposed flatwork, parking and driveareas assume that the owner and/or developer can tolerate minor amounts of settlement withinthese areas. The grading recommendations presented above do not mitigate the extent ofundocumented fill or compressible/collapsible native alluvium in the flatwork, parking and driveareas. As such, some settlement and associated pavement distress could occur. Typically, repairof such distressed areas involves significantly lower costs than completely mitigating these soilsat the time of construction. If the owner cannot tolerate the risk of such settlements, the flatwork,parking and drive areas should be overexcavated to a depth of 2 feet below proposed pavementsubgrade elevation, with the resulting soils replaced as compacted structural fill.

Fill Placement

Fill soils should be placed in thin (6± inches), near-horizontal lifts, moisture conditionedto 0 to 4 percent above the optimum moisture content, and compacted.

On-site soils may be used for fill provided they are cleaned of any debris to the satisfactionof the geotechnical engineer.

All grading and fill placement activities should be completed in accordance with therequirements of the 2016 CBC and the grading code of the County of San Bernardino.

All fill soils should be compacted to at least 90 percent of the ASTM D-1557 maximum drydensity. Fill soils should be well mixed.

Compaction tests should be performed periodically by the geotechnical engineer asrandom verification of compaction and moisture content. These tests are intended to aidthe contractor. Since the tests are taken at discrete locations and depths, they may notbe indicative of the entire fill and therefore should not relieve the contractor of hisresponsibility to meet the job specifications.


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Selective Grading and Oversized Material Placement

The existing soils beginning from the ground surface possess moderate cobble content. It isexpected that large scrapers (Caterpillar 657 or equivalent) will be adequate to move the cobblecontaining soils as well as some of the soils containing smaller boulders. Although not readilyobserved in the boring locations, some large boulders (2± feet in size) are expected toencountered at the subject site. It will likely be necessary to move such larger bouldersindividually, and place them as oversized materials in accordance with the Grading GuideSpecifications, in Appendix D of this report.

Since the proposed grading will require excavation of cobble and boulder containing soils, it maybe desirable to selectively grade the proposed building pad area. The presence of particles greaterthan 3 inches in diameter within the upper 1 to 3 feet of the building pad subgrade will impactthe utility and foundation excavations. Depending on the depths of fills required within theproposed parking areas, it may be feasible to sort the on-site soils, placing the materials greaterthan 3 inches in diameter within the lower depths of the fills, and limiting the upper 1 to 3 feetof soils to materials less than 3 inches in size. Oversized materials could also be placed within thelower depths of the recommended overexcavations. In order to achieve this grading, it wouldlikely be necessary to use rock buckets and/or rock sieves to separate the oversized materialsfrom the remaining soil. Although such selective grading will facilitate further constructionactivities, it is not considered mandatory and a suitable subgrade could be achieved without suchextensive sorting. However, in any case it is recommended that all materials greater than 6 inchesin size be excluded from the upper 1 foot of the surface of any compacted fills. The placementof any oversized materials should be performed in accordance with the grading guidespecifications included in Appendix D of this report. If disposal of oversized materials isrequired, rock blankets or windrows should be used and such areas should be observed duringconstruction and placement by a representative of the geotechnical engineer.

Imported Structural Fill

All imported structural fill should consist of very low expansive (EI < 20), well graded soilspossessing at least 10 percent fines (that portion of the sample passing the No. 200 sieve).Additional specifications for structural fill are presented in the Grading Guide Specifications,included as Appendix D.

Utility Trench Backfill

In general, all utility trench backfill soils should be compacted to at least 90 percent of the ASTMD-1557 maximum dry density. It is recommended that materials in excess of 3 inches in size notbe used for utility trench backfill. Compacted trench backfill should conform to the requirementsof the local grading code, and more restrictive requirements may be indicated by County of SanBernardino. All utility trench backfills should be witnessed by the geotechnical engineer. Thetrench backfill soils should be compaction tested where possible; probed and visually evaluatedelsewhere.

Utility trenches which parallel a footing, and extending below a 1h:1v plane projected from theoutside edge of the footing should be backfilled with structural fill soils, compacted to at least 90percent of the ASTM D-1557 standard. Pea gravel backfill should not be used for these trenches.


Page 17

6.4 Construction Considerations

Moisture Sensitive Subgrade Soils

Some of the near surface soils possess appreciable silt content and may become unstable ifexposed to significant moisture infiltration or disturbance by construction traffic. In addition,based on their granular content, some of the on-site soils will also be susceptible to erosion. Thesite should, therefore, be graded to prevent ponding of surface water and to prevent water fromrunning into excavations.

Excavation Considerations

The near surface soils generally consist of loose to medium dense silty sands and fine to mediumsands. These materials are expected to be subject to caving within shallow excavations. Wherecaving occurs within shallow excavations, flattened excavation slopes may be sufficient to provideexcavation stability. On a preliminary basis, temporary excavation slopes should be no steeperthan 2h:1v. Deeper excavations may require some form of external stabilization such as shoringor bracing. Maintaining adequate moisture content within the near-surface soils will improveexcavation stability. All excavation activities on this site should be conducted in accordance withCal-OSHA regulations.

Groundwater

Based on the lack of any free water at the boring locations, the static groundwater table at thissite is considered to exist at a depth in excess of 20± feet. Therefore, groundwater is not expectedto impact grading or foundation construction activities.

6.5 Foundation Design and Construction

Based on the preceding grading recommendations, it is assumed that the new building pad willbe underlain by structural fill soils used to replace existing undocumented fill soils and the upper-portion of the alluvium. These new structural fill soils are expected to extend to depths of at least3 feet below proposed foundation bearing grade, underlain by 1± foot of additional soil that hasbeen densified and moisture conditioned in place. Based on this subsurface profile, the proposedstructure may be supported on conventional shallow foundations.

Foundation Design Parameters

New square and rectangular footings may be designed as follows:

Maximum, net allowable soil bearing pressure: 2,500 lbs/ft2.

Minimum wall/column footing width: 14 inches/24 inches.

Minimum longitudinal steel reinforcement within strip footings: Two (2) No. 5 rebars (1top and 1 bottom).


Page 18

Minimum foundation embedment: 12 inches into suitable structural fill soils, and at least18 inches below adjacent exterior grade. Interior column footings may be placedimmediately beneath the floor slab.

It is recommended that the perimeter building foundations be continuous across allexterior doorways. Any flatwork adjacent to the exterior doors should be doweled into theperimeter foundations in a manner determined by the structural engineer.

The allowable bearing pressures presented above may be increased by 1/3 when consideringshort duration wind or seismic loads. The minimum steel reinforcement recommended above isbased on geotechnical considerations; additional reinforcement may be necessary for structuralconsiderations. The actual design of the foundations should be determined by the structuralengineer.

Foundation Construction

The foundation subgrade soils should be evaluated at the time of overexcavation, as discussedin Section 6.3 of this report. It is further recommended that the foundation subgrade soils beevaluated by the geotechnical engineer immediately prior to steel or concrete placement. Soilssuitable for direct foundation support should consist of newly placed structural fill, compacted toat least 90 percent of the ASTM D-1557 maximum dry density. Any unsuitable materials shouldbe removed to a depth of suitable bearing compacted structural fill or suitable native alluvium(where reduced bearing pressures are utilized), with the resulting excavations backfilled withcompacted fill soils. As an alternative, lean concrete slurry (500 to 1,500 psi) may be used tobackfill such isolated overexcavations.

The foundation subgrade soils should also be properly moisture conditioned to 0 to 4 percentabove the Modified Proctor optimum, to a depth of at least 12 inches below bearing grade. Sinceit is typically not feasible to increase the moisture content of the floor slab and foundationsubgrade soils once rough grading has been completed, care should be taken to maintain themoisture content of the building pad subgrade soils throughout the construction process.

Estimated Foundation Settlements

Post-construction total and differential settlements of shallow foundations designed andconstructed in accordance with the previously presented recommendations are estimated to beless than 1.0 and 0.5 inches, respectively. Differential movements are expected to occur over a50-foot span, thereby resulting in an angular distortion of less than 0.002 inches per inch.

Lateral Load Resistance

Lateral load resistance will be developed by a combination of friction acting at the base offoundations and slabs and the passive earth pressure developed by footings below grade. Thefollowing friction and passive pressure may be used to resist lateral forces:

Passive Earth Pressure: 300 lbs/ft3

Friction Coefficient: 0.30


Page 19

These are allowable values, and include a factor of safety. When combining friction and passiveresistance, the passive pressure component should be reduced by one-third. These values assumethat footings will be poured directly against compacted structural fill. The maximum allowablepassive pressure is 2,500 lbs/ft2.

6.6 Floor Slab Design and Construction

Subgrades which will support new floor slabs should be prepared in accordance with therecommendations contained in the Site Grading Recommendations section of this report.Based on the anticipated grading which will occur at this site, the floor of the new structure maybe constructed as a conventional slab-on-grade supported on newly placed structural fill,extending to a depth of at least 4 feet below proposed finished grade. Based on geotechnicalconsiderations, the floor slab may be designed as follows:

Minimum slab thickness: 6 inches.

Minimum slab reinforcement: Not required for geotechnical considerations. The actualfloor slab reinforcement should be determined by the structural engineer, based upon theimposed loading.

Modulus of Subgrade Reaction: 150 psi/in.

Slab underlayment: If moisture sensitive floor coverings will be used then minimum slabunderlayment should consist of a moisture vapor barrier constructed below the entire slabarea where such moisture sensitive floor coverings are expected. The moisture vaporbarrier should meet or exceed the Class A rating as defined by ASTM E 1745-97 and havea permeance rating less than 0.01 perms as described in ASTM E 96-95 and ASTM E 154-88. A polyolefin material such as 15 mil Stego® Wrap Vapor Barrier or equivalent will meetthese specifications. The moisture vapor barrier should be properly constructed inaccordance with all applicable manufacturer specifications. Given that a rock freesubgrade is anticipated and that a capillary break is not required, sand below the barrieris not required. The need for sand and/or the amount of sand above the moisture vaporbarrier should be specified by the structural engineer or concrete contractor. The selectionof sand above the barrier is not a geotechnical engineering issue and hence outside ourpurview. Where moisture sensitive floor coverings are not anticipated, the vapor barriermay be eliminated.

Moisture condition the floor slab subgrade soils to 0 to 4 percent above the ModifiedProctor optimum moisture content, to a depth of 12 inches. The moisture content of thefloor slab subgrade soils should be verified by the geotechnical engineer within 24 hoursprior to concrete placement.

Proper concrete curing techniques should be utilized to reduce the potential for slabcurling or the formation of excessive shrinkage cracks.

The actual design of the floor slab should be completed by the structural engineer to verifyadequate thickness and reinforcement.


Page 20

6.7 Retaining Wall Design and Construction

Based on the proposed use of the site, it is expected that some small retaining walls (less than 5feet in height) will be required in the area of the new truck docks. The parameters recommendedfor use in the design of these walls are presented below.

Retaining Wall Design Parameters

Based on the soil conditions encountered at the boring locations, the following parameters maybe used in the design of new retaining walls for this site. We have provided parameters assumingthe use of on-site soils for retaining wall backfill. The near surface soils generally consist of siltysands and fine to medium sands. Based on their classifications, the on-site soils are expected topossess a friction angle of at least 30 degrees when compacted to 90 percent of the ASTM-1557maximum dry density.

If desired, SCG could provide design parameters for an alternative select backfill material behindthe retaining walls. The use of select backfill material could result in lower lateral earth pressures.In order to use the design parameters for the imported select fill, this material must be placedwithin the entire active failure wedge. This wedge is defined as extending from the heel of theretaining wall upwards at an angle of approximately 60° from horizontal. If select backfill materialbehind the retaining wall is desired, SCG should be contacted for supplementaryrecommendations.

RETAINING WALL DESIGN PARAMETERS

Design Parameter

Soil Type

On-Site Silty Sandsand Sands

Internal Friction Angle () 30

Unit Weight 130 lbs/ft3

Equivalent FluidPressure:

Active Condition(level backfill)

44 lbs/ft3

Active Condition(2h:1v backfill)

69 lbs/ft3

At-Rest Condition(level backfill)

65 lbs/ft3

Regardless of the backfill type, the walls should be designed using a soil-footing coefficient offriction of 0.30 and an equivalent passive pressure of 300 lbs/ft3. The structural engineer shouldincorporate appropriate factors of safety in the design of the retaining walls.

The active earth pressure may be used for the design of retaining walls that do not directlysupport structures or support soils that in turn support structures and which will be allowed todeflect. The at-rest earth pressure should be used for walls that will not be allowed to deflectsuch as those which will support foundation bearing soils, or which will support foundation loadsdirectly.


Page 21

Where the soils on the toe side of the retaining wall are not covered by a "hard" surface such asa structure or pavement, the upper 1 foot of soil should be neglected when calculating passiveresistance due to the potential for the material to become disturbed or degraded during the lifeof the structure.

Seismic Lateral Earth Pressures

In accordance with the 2016 CBC, any retaining walls more than 6 feet in height must be designedfor seismic lateral earth pressures. If walls 6 feet or more are required for this site, thegeotechnical engineer should be contacted for supplementary seismic lateral earth pressurerecommendations.

Retaining Wall Foundation Design

The retaining wall foundations should be supported within newly placed compacted structural fill,extending to a depth of at least 3 feet below the proposed bearing grade. Foundations to supportnew retaining walls should be designed in accordance with the general Foundation DesignParameters presented in a previous section of this report.

Backfill Material

On-site soils may be used to backfill the retaining walls. However, all backfill material placedwithin 3 feet of the back wall face should have a particle size no greater than 3 inches. Theretaining wall backfill materials should be well graded.

It is recommended that a properly installed prefabricated drainage composite such as theMiraDRAIN 6000XL (or approved equivalent), which is specifically designed for use behindretaining walls be used. If the drainage composite material is not covered by an impermeablesurface, such as a structure or pavement, a 12-inch thick layer of a low permeability soil shouldbe placed over the backfill to reduce surface water migration to the underlying soils. The drainagecomposite should be separated from the backfill soils by a suitable geotextile, approved by thegeotechnical engineer.

All retaining wall backfill should be placed and compacted under engineering controlled conditionsin the necessary layer thicknesses to ensure an in-place density between 90 and 93 percent ofthe maximum dry density as determined by the Modified Proctor test (ASTM D1557). Care shouldbe taken to avoid over-compaction of the soils behind the retaining walls, and the use of heavycompaction equipment should be avoided.

Subsurface Drainage

As previously indicated, the retaining wall design parameters are based upon drained backfillconditions. Consequently, some form of permanent drainage system will be necessary inconjunction with the appropriate backfill material. Subsurface drainage may consist of either:

A weep hole drainage system typically consisting of a series of 4-inch diameter holes inthe wall situated slightly above the ground surface elevation on the exposed side of the


Page 22

wall and at an approximate 8-foot on-center spacing. The weep holes should include apocket of gravel, 2± cubic feet in size, surrounded by a geotextile fabric, at each weephole location.

A 4-inch diameter perforated pipe surrounded by 2 cubic feet of gravel per linear foot ofdrain placed behind the wall, above the retaining wall footing. The gravel layer should bewrapped in a suitable geotextile fabric to reduce the potential for migration of fines. Thefooting drain should be extended to daylight or tied into a storm drainage system.

6.8 Pavement Design Parameters

Site preparation in the pavement area should be completed as previously recommended in theSite Grading Recommendations section of this report. The subsequent pavementrecommendations assume proper drainage and construction monitoring, and are based on eitherPCA or CALTRANS design parameters for a twenty (20) year design period. However, thesedesigns also assume a routine pavement maintenance program to obtain the anticipated 20-yearpavement service life.

Pavement Subgrades

It is anticipated that the new pavements will be primarily supported on a layer of compactedstructural fill, consisting of scarified, thoroughly moisture conditioned and recompacted existingsoils. The near-surface soils generally consist of silty sands and fine to coarse sands with varyinggravel content. These soils are considered to possess excellent pavement support characteristicswith estimated R-values of 50 to 60. Since R-value testing was not included in the scope ofservices for this project, the subsequent pavement design is based upon an assumed R-value of50. Any fill material imported to the site should have support characteristics equal to or greaterthan that of the on-site soils and be placed and compacted under engineering controlledconditions. It is recommended that R-value testing be performed after completion of roughgrading.

Asphaltic Concrete

Presented below are the recommended thicknesses for new flexible pavement structuresconsisting of asphaltic concrete over a granular base. The pavement designs are based on thetraffic indices (TI’s) indicated. The client and/or civil engineer should verify that these TI’s arerepresentative of the anticipated traffic volumes. If the client and/or civil engineer determine thatthe expected traffic volume will exceed the applicable traffic index, we should be contacted forsupplementary recommendations. The design traffic indices equate to the following approximatedaily traffic volumes over a 20 year design life, assuming six operational traffic days per week.

Traffic Index No. of Heavy Trucks per Day

4.0 0

5.0 1

6.0 3

7.0 11

8.0 35


Page 23

For the purpose of the traffic volumes indicated above, a truck is defined as a 5-axle tractor trailerunit with one 8-kip axle and two 32-kip tandem axles. All of the traffic indices allow for 1,000automobiles per day.


Materials

Thickness (inches)


(TI = 4.0 & 5.0)

Truck Traffic

(TI = 6.0) (TI = 7.0) (TI = 8.0)




The aggregate base course should be compacted to at least 95 percent of the ASTM D-1557maximum dry density. The asphaltic concrete should be compacted to at least 95 percent of theMarshall maximum density, as determined by ASTM D-2726. The aggregate base course mayconsist of crushed aggregate base (CAB) or crushed miscellaneous base (CMB), which is arecycled gravel, asphalt and concrete material. The gradation, R-Value, Sand Equivalent, andPercentage Wear of the CAB or CMB should comply with appropriate specifications contained inthe current edition of the “Greenbook” Standard Specifications for Public Works Construction.

Portland Cement Concrete

The preparation of the subgrade soils within concrete pavement areas should be performed aspreviously described for proposed asphalt pavement areas. The minimum recommendedthicknesses for the Portland Cement Concrete pavement sections are as follows:

PORTLAND CEMENT CONCRETE PAVEMENTS (R = 50)

Materials

Thickness (inches)

Automobile andLight Truck Traffic(TI = 5.0 & 6.0)

Moderate TruckTraffic

(TI =7.0)

Heavy Truck Traffic(TI =8.0)

PCC 5 6 7

Compacted Subgrade(95% minimum compaction)

12 12 12

The concrete should have a 28-day compressive strength of at least 3,000 psi. The maximumjoint spacing within all of the PCC pavements is recommended to be equal to or less than 30times the pavement thickness.


Page 24

7.0 GENERAL COMMENTS

This report has been prepared as an instrument of service for use by the client, in order to aid inthe evaluation of this property and to assist the architects and engineers in the design andpreparation of the project plans and specifications. This report may be provided to thecontractor(s) and other design consultants to disclose information relative to the project.However, this report is not intended to be utilized as a specification in and of itself, withoutappropriate interpretation by the project architect, civil engineer, and/or structural engineer. Thereproduction and distribution of this report must be authorized by the client and SouthernCalifornia Geotechnical, Inc. Furthermore, any reliance on this report by an unauthorized thirdparty is at such party’s sole risk, and we accept no responsibility for damage or loss which mayoccur. The client(s)’ reliance upon this report is subject to the Engineering Services Agreement,incorporated into our proposal for this project.

The analysis of this site was based on a subsurface profile interpolated from limited discrete soilsamples. While the materials encountered in the project area are considered to be representativeof the total area, some variations should be expected between boring locations and sampledepths. If the conditions encountered during construction vary significantly from those detailedherein, we should be contacted immediately to determine if the conditions alter therecommendations contained herein.

This report has been based on assumed or provided characteristics of the proposed development.It is recommended that the owner, client, architect, structural engineer, and civil engineercarefully review these assumptions to ensure that they are consistent with the characteristics ofthe proposed development. If discrepancies exist, they should be brought to our attention toverify that they do not affect the conclusions and recommendations contained herein. We alsorecommend that the project plans and specifications be submitted to our office for review toverify that our recommendations have been correctly interpreted.

The analysis, conclusions, and recommendations contained within this report have beenpromulgated in accordance with generally accepted professional geotechnical engineeringpractice. No other warranty is implied or expressed.

S

IT

E

PROPOSED ALDER LOGISTICS CENTER

SCALE: 1" = 2400'

DRAWN: JLL

CHKD: GKM

SCG PROJECT

18G218-1

PLATE 1

SITE LOCATION MAP

SAN BERNARDINO COUNTY, CALIFORNIA

SOURCE: SAN BERNARDINO COUNTY

THOMAS GUIDE, 2013

10,000 GALLON RAIN CAPTURE

BASIN APPROXIMATE LOCATION

APPROXIMATE FORMER

UST AREA

APPROXIMATE SEPTIC

SYSTEM AREA

APPROXIMATE SEPTIC

SYSTEM AREA

SCALE: 1" = 80'

DRAWN: JLL

CHKD: GKM

PLATE 2

SCG PROJECT

18G218-1

SAN BERNARDINO COUNTY, CALIFORNIA

PROPOSED ALDER LOGISTICS CENTER

BORING LOCATION PLAN

GEOTECHNICAL LEGEND

So

Ca

lG

eo

NOTE: SITE PLAN PREPARED BY SB&O, INC.

APPROXIMATE BORING LOCATION FROM PREVIOUS

STUDY (SCG PROJECT NO. 18G112-1)

EXISTING BUILDINGS AND BRINE TANKS TO BE

DEMOLISHED

BORING LOG LEGEND SAMPLE TYPE GRAPHICAL SYMBOL SAMPLE DESCRIPTION

AUGER

SAMPLE COLLECTED FROM AUGER CUTTINGS, NO FIELD MEASUREMENT OF SOIL STRENGTH. (DISTURBED)

CORE ROCK CORE SAMPLE: TYPICALLY TAKEN WITH A

DIAMOND-TIPPED CORE BARREL. TYPICALLY USED ONLY IN HIGHLY CONSOLIDATED BEDROCK.

GRAB SOIL SAMPLE TAKEN WITH NO SPECIALIZED EQUIPMENT, SUCH AS FROM A STOCKPILE OR THE GROUND SURFACE. (DISTURBED)

CS CALIFORNIA SAMPLER: 2-1/2 INCH I.D. SPLIT BARREL

SAMPLER, LINED WITH 1-INCH HIGH BRASS RINGS. DRIVEN WITH SPT HAMMER. (RELATIVELY UNDISTURBED)

NSR

NO RECOVERY: THE SAMPLING ATTEMPT DID NOT RESULT IN RECOVERY OF ANY SIGNIFICANT SOIL OR ROCK MATERIAL.

SPT STANDARD PENETRATION TEST: SAMPLER IS A 1.4 INCH INSIDE DIAMETER SPLIT BARREL, DRIVEN 18 INCHES WITH THE SPT HAMMER. (DISTURBED)

SH SHELBY TUBE: TAKEN WITH A THIN WALL SAMPLE TUBE, PUSHED INTO THE SOIL AND THEN EXTRACTED. (UNDISTURBED)

VANE VANE SHEAR TEST: SOIL STRENGTH OBTAINED USING

A 4 BLADED SHEAR DEVICE. TYPICALLY USED IN SOFT CLAYS-NO SAMPLE RECOVERED.

COLUMN DESCRIPTIONS DEPTH: Distance in feet below the ground surface.

SAMPLE: Sample Type as depicted above.

BLOW COUNT: Number of blows required to advance the sampler 12 inches using a 140 lb hammer with a 30-inch drop. 50/3” indicates penetration refusal (>50 blows) at 3 inches. WH indicates that the weight of the hammer was sufficient to push the sampler 6 inches or more.

POCKET PEN.: Approximate shear strength of a cohesive soil sample as measured by pocket penetrometer.

GRAPHIC LOG: Graphic Soil Symbol as depicted on the following page.

DRY DENSITY: Dry density of an undisturbed or relatively undisturbed sample in lbs/ft3.

MOISTURE CONTENT: Moisture content of a soil sample, expressed as a percentage of the dry weight.

LIQUID LIMIT: The moisture content above which a soil behaves as a liquid.

PLASTIC LIMIT: The moisture content above which a soil behaves as a plastic.

PASSING #200 SIEVE: The percentage of the sample finer than the #200 standard sieve.

UNCONFINED SHEAR: The shear strength of a cohesive soil sample, as measured in the unconfined state.

SM

SP

COARSEGRAINED

SOILS

SW

TYPICALDESCRIPTIONS

WELL-GRADED GRAVELS, GRAVEL -SAND MIXTURES, LITTLE OR NOFINES

SILTY GRAVELS, GRAVEL - SAND -SILT MIXTURES

LETTERGRAPH

POORLY-GRADED GRAVELS,GRAVEL - SAND MIXTURES, LITTLEOR NO FINES

GC

GM

GP

GW

POORLY-GRADED SANDS,GRAVELLY SAND, LITTLE OR NOFINES

SILTSAND

CLAYS

MORE THAN 50%OF MATERIAL ISLARGER THANNO. 200 SIEVE

SIZE

MORE THAN 50%OF MATERIAL ISSMALLER THANNO. 200 SIEVE

SIZE

MORE THAN 50%OF COARSEFRACTION

PASSING ON NO.4 SIEVE

MORE THAN 50%OF COARSEFRACTION

RETAINED ON NO.4 SIEVE CLAYEY GRAVELS, GRAVEL - SAND -

CLAY MIXTURES

FINEGRAINED

SOILS

SYMBOLSMAJOR DIVISIONS

SOIL CLASSIFICATION CHART

PT

OH

CH

MH

OL

CL

ML

CLEAN SANDS

SC

SILTY SANDS, SAND - SILTMIXTURES

CLAYEY SANDS, SAND - CLAYMIXTURES

INORGANIC SILTS AND VERY FINESANDS, ROCK FLOUR, SILTY ORCLAYEY FINE SANDS OR CLAYEYSILTS WITH SLIGHT PLASTICITY

INORGANIC CLAYS OF LOW TOMEDIUM PLASTICITY, GRAVELLYCLAYS, SANDY CLAYS, SILTY CLAYS,LEAN CLAYS

ORGANIC SILTS AND ORGANICSILTY CLAYS OF LOW PLASTICITY

INORGANIC SILTS, MICACEOUS ORDIATOMACEOUS FINE SAND ORSILTY SOILS

INORGANIC CLAYS OF HIGHPLASTICITY

ORGANIC CLAYS OF MEDIUM TOHIGH PLASTICITY, ORGANIC SILTS

PEAT, HUMUS, SWAMP SOILS WITHHIGH ORGANIC CONTENTS

SILTSAND

CLAYS

GRAVELS WITHFINES

SANDAND

SANDYSOILS (LITTLE OR NO FINES)

SANDS WITHFINES

LIQUID LIMITLESS THAN 50

LIQUID LIMITGREATER THAN 50

HIGHLY ORGANIC SOILS

NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS

GRAVELAND

GRAVELLYSOILS

(APPRECIABLEAMOUNT OF FINES)

(APPRECIABLEAMOUNT OF FINES)

(LITTLE OR NO FINES)

WELL-GRADED SANDS, GRAVELLYSANDS, LITTLE OR NO FINES

CLEANGRAVELS

10

7

47

17

20

50

67

3± inches Asphaltic concrete, no discernible Aggregate baseFILL: Brown to Gray Brown Silty fine Sand, trace coarse Sand,loose-damp to moist

ALLUVIUM: Light Gray Brown fine to coarse Sandy Gravel, traceto little Silt, extensive Cobbles, dense-damp to moist

Brown Silty fine Sand, trace fine Gravel, occasional Cobbles,medium dense-damp to moist

Light Gray Brown Silty fine to coarse Sand, little fine Gravel,occasional Cobbles, medum dense-damp to moist

Light Gray Brown fine to coarse Sand, trace Silt, little fine tocoarse Gravel, dense to very dense-damp

Boring Terminated at 20'

102

97

114

109

118

6

9

5

7

7

3

3

JOB NO.: 18G112PROJECT: Proposed WarehouseLOCATION: San Bernardino County, California

BORING NO.B-1

PLATE B-1

DRILLING DATE: 2/22/18DRILLING METHOD: Hollow Stem AugerLOGGED BY: Jason Hiskey

FIELD RESULTS LABORATORY RESULTS

CO

MM

EN

TS

SURFACE ELEVATION: --- MSL

WATER DEPTH: DryCAVE DEPTH: 5 feetREADING TAKEN: At Completion

5

10

15

20

GR

AP

HIC

LO

G

PA

SS

ING

#200

SIE

VE

(%

)

TEST BORING LOG

DESCRIPTION

PO

CK

ET

PE

N.

(TS

F)

UN

CO

NF

INE

DS

HE

AR

(T

SF

)

DR

Y D

EN

SIT

Y(P

CF

)

DE

PT

H (

FE

ET

)

MO

IST

UR

EC

ON

TE

NT

(%

)

LIQ

UID

LIM

IT

PLA

ST

ICLI

MIT

SA

MP

LE

BLO

W C

OU

NT

TB

L 1

8G

112.

GP

J S

OC

ALG

EO

.GD

T 3

/6/1

8

6

22

15

20

75

2± inches Asphaltic concrete, no discernible Aggregate baseFILL: Gray Brown Silty fine Sand, trace medium to coarse Sand,loose-moist

ALLUVIUM: Light Gray Brown Gravelly fine to coarse Sand,occasional Cobbles, medium dense-damp

Gray Brown fine Sandy Silt, trace fine Gravel, medium dense-verymoist

Light Gray Brown to Gray fine to coarse Sand, little fine Gravel,trace Silt, occasional Cobbles, medium dense to very dense-damp


9

3

16

3

4


BORING NO.B-2

PLATE B-2



CO

MM

EN

TS



5

10

15

GR

AP

HIC

LO

G

PA

SS

ING

#200

SIE

VE

(%

)

TEST BORING LOG

DESCRIPTION

PO

CK

ET

PE

N.

(TS

F)

UN

CO

NF

INE

DS

HE

AR

(T

SF

)

DR

Y D

EN

SIT

Y(P

CF

)

DE

PT

H (

FE

ET

)

MO

IST

UR

EC

ON

TE

NT

(%

)

LIQ

UID

LIM

IT

PLA

ST

ICLI

MIT

SA

MP

LE

BLO

W C

OU

NT

TB

L 1

8G

112.

GP

J S

OC

ALG

EO

.GD

T 3

/6/1

8

15

29

30

14

16

41

21

2± inches Asphaltic concrete, no discernible Aggregate baseFILL: Brown Silty fine Sand, trace coarse Sand, trace fine Gravel,occasional Cobbles, trace Asphaltic concrete fragments, loose tomedium dense-moist

ALLUVIUM: Light Brown fine to coarse Sandy Gravel, trace Silt,occasional Cobbles, medium dense-damp

Light Gray Brown to Light Gray fine to medium Sand, little coarseSand, little fine Gravel, medium dense-damp

Brown Silty fine Sand, trace fine Gravel, medium dense-moist

Light Brown Silty fine to coarse Sand, little fine to coarse Gravel,occasional Cobbles, medium dense-moist

Light Gray Brown fine to coarse Sand, little Silt, litte fine to coarseGravel, occasional Cobbles, dense-damp

Light Brown Silty fine Sand to fine Sandy Silt, trace medium Sand,medium dense-moist to very moist


103

121

100

105

112

8

3

3

10

8

3

12


BORING NO.B-3

PLATE B-3



CO

MM

EN

TS



5

10

15

20

GR

AP

HIC

LO

G

PA

SS

ING

#200

SIE

VE

(%

)

TEST BORING LOG

DESCRIPTION

PO

CK

ET

PE

N.

(TS

F)

UN

CO

NF

INE

DS

HE

AR

(T

SF

)

DR

Y D

EN

SIT

Y(P

CF

)

DE

PT

H (

FE

ET

)

MO

IST

UR

EC

ON

TE

NT

(%

)

LIQ

UID

LIM

IT

PLA

ST

ICLI

MIT

SA

MP

LE

BLO

W C

OU

NT

TB

L 1

8G

112.

GP

J S

OC

ALG

EO

.GD

T 3

/6/1

8

7

9

10

32

43

35

2± inches Asphaltic concrete, no discernible Aggregate baseFILL: Brown Silty fine Sand, trace medium to coarse Sand,loose-moist

ALLUVIUM: Light Brown fine to medium Sand, little Silt, tracecoarse Sand, little fine to coarse Gravel, loose-damp

Brown Silty fine Sand, trace coarse Sand, little fine Gravel,medium dense-damp

Light Gray Brown Silty fine to coarse Sand, little fine to coarseGravel, occasional Cobbles, dense-damp


8

3

6

3

2

3


BORING NO.B-4

PLATE B-4



CO

MM

EN

TS



5

10

15

20

GR

AP

HIC

LO

G

PA

SS

ING

#200

SIE

VE

(%

)

TEST BORING LOG

DESCRIPTION

PO

CK

ET

PE

N.

(TS

F)

UN

CO

NF

INE

DS

HE

AR

(T

SF

)

DR

Y D

EN

SIT

Y(P

CF

)

DE

PT

H (

FE

ET

)

MO

IST

UR

EC

ON

TE

NT

(%

)

LIQ

UID

LIM

IT

PLA

ST

ICLI

MIT

SA

MP

LE

BLO

W C

OU

NT

TB

L 1

8G

112.

GP

J S

OC

ALG

EO

.GD

T 3

/6/1

8

38

28

22

53

60

26

21

6± inches Aggregate baseFILL: Light Gray Brown Silty fine to coarse Sand, little fine tocoarse Gravel, occasional Cobbles, medium dense-dampALLUVIUM: Gray Brown fine to coarse Sandy Gravel, extensiveCobbles, medium dense-dry to damp

Gray Gravelly fine to coarse Sand, occasional Cobbles, mediumdense-dry

Gray Brown Silty fine to medium Sand, little coarse Sand, little fineto coarse Gravel, occasional Cobbles, dense-damp

Dark Gray Gravelly fine to coarse Sand, trace Silt, dense-dry todamp

Brown Silty fine Sand to fine Sandy Silt, little fine to coarse Gravel,little Iron oxide staining, medium dense-very moist

Light Brown Silty fine Sand, medium dense-damp to moist


123

119

113

122

122

120

3

2

1

3

2

3

7


BORING NO.B-5

PLATE B-5



CO

MM

EN

TS



5

10

15

20

GR

AP

HIC

LO

G

PA

SS

ING

#200

SIE

VE

(%

)

TEST BORING LOG

DESCRIPTION

PO

CK

ET

PE

N.

(TS

F)

UN

CO

NF

INE

DS

HE

AR

(T

SF

)

DR

Y D

EN

SIT

Y(P

CF

)

DE

PT

H (

FE

ET

)

MO

IST

UR

EC

ON

TE

NT

(%

)

LIQ

UID

LIM

IT

PLA

ST

ICLI

MIT

SA

MP

LE

BLO

W C

OU

NT

TB

L 1

8G

112.

GP

J S

OC

ALG

EO

.GD

T 3

/6/1

8

6

20

2± inches Asphaltic concrete, no discernible Aggregate baseFILL: Brown Silty fine Sand, little fine Gravel, loose-moist

ALLUVIUM: Light Gray Brown Silty fine to medium Sand, littlecoarse Sand, little fine to coarse Gravel, medium dense-damp


7

6


BORING NO.B-6

PLATE B-6



CO

MM

EN

TS



5

GR

AP

HIC

LO

G

PA

SS

ING

#200

SIE

VE

(%

)

TEST BORING LOG

DESCRIPTION

PO

CK

ET

PE

N.

(TS

F)

UN

CO

NF

INE

DS

HE

AR

(T

SF

)

DR

Y D

EN

SIT

Y(P

CF

)

DE

PT

H (

FE

ET

)

MO

IST

UR

EC

ON

TE

NT

(%

)

LIQ

UID

LIM

IT

PLA

ST

ICLI

MIT

SA

MP

LE

BLO

W C

OU

NT

TB

L 1

8G

112.

GP

J S

OC

ALG

EO

.GD

T 3

/6/1

8

Classification: FILL: Brown to Gray Brown Silty fine Sand, trace coarse Sand

Boring Number: B-1 Initial Moisture Content (%) 6

Sample Number: --- Final Moisture Content (%) 16

Depth (ft) 1 to 2 Initial Dry Density (pcf) 101.8

Specimen Diameter (in) 2.4 Final Dry Density (pcf) 110.1

Specimen Thickness (in) 1.0 Percent Collapse (%) 2.23

Proposed WarehouseSan Bernardino County, CaliforniaProject No. 18G112

PLATE C- 1

0

2

4

6

8

10

12

14

16

18

200.1 1 10 100

Co

nso

lid

ati

on

Str

ain

(%)

Load (ksf)

Consolidation/Collapse Test Results

Water Addedat 1600 psf

Classification: FILL: Brown to Gray Brown Silty fine Sand, trace coarse Sand







PLATE C- 2

0

2

4

6

8

10

12

14

16

18

200.1 1 10 100

Co

nso

lid

ati

on

Str

ain

(%)

Load (ksf)



Classification: Light Gray Brown fine to coarse Sandy Gravel, trace to little Silt







PLATE C- 3

0

2

4

6

8

10

12

14

16

18

200.1 1 10 100

Co

nso

lid

ati

on

Str

ain

(%)

Load (ksf)



Classification: Brown Silty fine Sand, trace fine Gravel, occasional Cobbles







PLATE C- 4

0

2

4

6

8

10

12

14

16

18

200.1 1 10 100

Co

nso

lid

ati

on

Str

ain

(%)

Load (ksf)




PLATE C-5

108

110

112

114

116

118

120

122

124

126

128

130

132

134

4 6 8 10 12 14 16 18

Dry

Den

sit

y(l

bs/f

t3)

Moisture Content (%)

Moisture/Density RelationshipASTM D-1557

Soil ID Number B-3 @ 0 to 5'Optimum Moisture (%) 8.5

Maximum Dry Density (pcf) 129.5

Soil

Classification Brown Silty fine Sand, little fine tocoarse Gravel

Zero Air Voids Curve:Specific Gravity = 2.7

Grading Guide Specifications Page 1 GRADING GUIDE SPECIFICATIONS These grading guide specifications are intended to provide typical procedures for grading operations. They are intended to supplement the recommendations contained in the geotechnical investigation report for this project. Should the recommendations in the geotechnical investigation report conflict with the grading guide specifications, the more site specific recommendations in the geotechnical investigation report will govern. General

• The Earthwork Contractor is responsible for the satisfactory completion of all earthwork in accordance with the plans and geotechnical reports, and in accordance with city, county, and applicable building codes.

• The Geotechnical Engineer is the representative of the Owner/Builder for the purpose of

implementing the report recommendations and guidelines. These duties are not intended to relieve the Earthwork Contractor of any responsibility to perform in a workman-like manner, nor is the Geotechnical Engineer to direct the grading equipment or personnel employed by the Contractor.

• The Earthwork Contractor is required to notify the Geotechnical Engineer of the anticipated

work and schedule so that testing and inspections can be provided. If necessary, work may be stopped and redone if personnel have not been scheduled in advance.

• The Earthwork Contractor is required to have suitable and sufficient equipment on the job-

site to process, moisture condition, mix and compact the amount of fill being placed to the approved compaction. In addition, suitable support equipment should be available to conform with recommendations and guidelines in this report.

• Canyon cleanouts, overexcavation areas, processed ground to receive fill, key excavations,

subdrains and benches should be observed by the Geotechnical Engineer prior to placement of any fill. It is the Earthwork Contractor's responsibility to notify the Geotechnical Engineer of areas that are ready for inspection.

• Excavation, filling, and subgrade preparation should be performed in a manner and

sequence that will provide drainage at all times and proper control of erosion. Precipitation, springs, and seepage water encountered shall be pumped or drained to provide a suitable working surface. The Geotechnical Engineer must be informed of springs or water seepage encountered during grading or foundation construction for possible revision to the recommended construction procedures and/or installation of subdrains.

Site Preparation

• The Earthwork Contractor is responsible for all clearing, grubbing, stripping and site preparation for the project in accordance with the recommendations of the Geotechnical Engineer.

• If any materials or areas are encountered by the Earthwork Contractor which are suspected

of having toxic or environmentally sensitive contamination, the Geotechnical Engineer and Owner/Builder should be notified immediately.

Grading Guide Specifications Page 2

• Major vegetation should be stripped and disposed of off-site. This includes trees, brush, heavy grasses and any materials considered unsuitable by the Geotechnical Engineer.

• Underground structures such as basements, cesspools or septic disposal systems, mining

shafts, tunnels, wells and pipelines should be removed under the inspection of the Geotechnical Engineer and recommendations provided by the Geotechnical Engineer and/or city, county or state agencies. If such structures are known or found, the Geotechnical Engineer should be notified as soon as possible so that recommendations can be formulated.

• Any topsoil, slopewash, colluvium, alluvium and rock materials which are considered

unsuitable by the Geotechnical Engineer should be removed prior to fill placement.

• Remaining voids created during site clearing caused by removal of trees, foundations basements, irrigation facilities, etc., should be excavated and filled with compacted fill.

• Subsequent to clearing and removals, areas to receive fill should be scarified to a depth of

10 to 12 inches, moisture conditioned and compacted • The moisture condition of the processed ground should be at or slightly above the optimum

moisture content as determined by the Geotechnical Engineer. Depending upon field conditions, this may require air drying or watering together with mixing and/or discing.

Compacted Fills

• Soil materials imported to or excavated on the property may be utilized in the fill, provided each material has been determined to be suitable in the opinion of the Geotechnical Engineer. Unless otherwise approved by the Geotechnical Engineer, all fill materials shall be free of deleterious, organic, or frozen matter, shall contain no chemicals that may result in the material being classified as “contaminated,” and shall be very low to non-expansive with a maximum expansion index (EI) of 50. The top 12 inches of the compacted fill should have a maximum particle size of 3 inches, and all underlying compacted fill material a maximum 6-inch particle size, except as noted below.

• All soils should be evaluated and tested by the Geotechnical Engineer. Materials with high

expansion potential, low strength, poor gradation or containing organic materials may require removal from the site or selective placement and/or mixing to the satisfaction of the Geotechnical Engineer.

• Rock fragments or rocks less than 6 inches in their largest dimensions, or as otherwise

determined by the Geotechnical Engineer, may be used in compacted fill, provided the distribution and placement is satisfactory in the opinion of the Geotechnical Engineer.

• Rock fragments or rocks greater than 12 inches should be taken off-site or p

appendix f updated geotechnical investigation...(ti = 6.0) (ti = 7.0) (ti = 8.0) asphalt concrete 3...

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