re: geotechnical letter american river college re … arc re-paving geotechnical...geotechnical...

1Terracon Consultants, Inc. 50 Goldenland Ct. # 100 Sacramento, CA 95834P [916] 928 4690 F [916] 928 4697 terracon.com

March 30, 2017

3753 Bradview DriveSacramento, CA 95827

Attn: Mr. Peter Bowman, Grounds SupervisorP: (916) 856-3412M: (916) 730-7408E: [email protected]

Re: Geotechnical LetterAmerican River College Re-Paving Project4700 College Oak DriveSacramento, California 95841Terracon Project No. NB171011

Dear Mr. Bowman:

It is our understanding that pavement rehabilitation is planned for a section of the American RiverCollege Campus (ARC). Neil O. Anderson & Associates (A Terracon Company) previouslyprepared a number of geotechnical reports for improvements to the existing ARC Campus. TheARC Athletic Field Project (our Project No. SGE140020 revised January 27, 2015) is locateddirectly adjacent to the proposed pavement rehabilitation project. Pursuant to your request, weare providing the following letter which provides grading recommendations and pavementrecommendations for the proposed project which utilizes the findings of our previous report.

It is our understanding that the flexible pavements located to the adjacent northwest of thenewly constructed athletic field are deteriorating and in need of repair. A geotechnical engineerfrom our office visited the site on March 17, 2017. Aside from the construction of the newathletic field, site conditions are consistent with those described in our previous report(SGE140020). We conclude that the grading recommendations and flexible pavementrecommendations provided in our previous report are suitable for use on this project

No structural or civil plans were reviewed for this project at the time of preparation of this letter.Any future development of the site will need to be reviewed by a qualified geotechnicalconsultant and appropriate recommendations need to be provided based on the site subsurfaceconditions.

Geotechnical LetterARC Re-Paving Project Sacramento, CAMarch 30, 2017 Terracon Project No. NB171011

Resourceful Reliable Responsive 2

Terracon should be retained to provide geotechnical and materials testing services in support offuture development of the site including reviews of plans, preparation of supplemental reports,and providing observation and testing services during earthwork and construction.

The analyses and comments in this letter are based in part upon data obtained from the fieldexploration conducted for the athletic fields located adjacent to the proposed improvements.The nature and extent of variations beyond the location of the test borings may not becomeevident until construction. If variations then appear evident, it may be necessary to re-evaluateour recommendations.

We appreciate being of service to you in the geotechnical engineering phase of this project, andare prepared to assist you during the construction phases as well. If you have any questionsconcerning this report or any of our testing, inspection, design, and consulting services, pleasecontact us.

Sincerely,Terracon Consultants, Inc.

Nicholas Novotny, G.I.T. Robert E. Holmer, G.E.Staff Geologist Office Manager

Attached: Exhibit A-1 Assumed Project ExtentsExhibit A-2 Geotechnical Report - American River College Athletic fields, SGE140020

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©2014 Neil O. Anderson & Associates, Inc., a Terracon Company

GEOTECHNICAL INVESTIGATION

AMERICAN RIVER COLLEGE ATHLETIC FIELDS

4700 COLLAGE OAK DRIVE

SACRAMENTO, CALIFORNIA

REPORT PREPARED FOR:

LOS RIOS COMMUNITY COLLEGE DISTRICT

OUR PROJECT NUMBER: SGE140020

Revised January 27, 2015

This document was prepared for use only by the client, only for the purposes stated, and within a reasonable time from issuance. Non-commercial,educational, and scientific use of this report by regulatory agencies is regarded as a “fair use” and not a violation of copyright. Regulatoryagencies may make additional copies of this document for internal use. Copies may also be made available to the public as required by law. Thereprint must acknowledge the copyright and indicate that permission to reprint has been received.

Lodi • Sacramento • ConcordPhone: 916.928.4690 • Fax: 916.928.4697 • www.noanderson.com

50 Goldenland Court, #100, Sacramento, CA 95834

GEOTECHNICAL ENGINEERING

TESTING AND INSPECTION SERVICES

CERTIFIED LABORATORIES

ENVIRONMENTAL SERVICES

FOUNDATION ENGINEERING

AQUATIC DESIGN AND ENGINEERING

RENEWABLE ENERGY RESOURCES

Revised January 27, 2015Our Project Number: SGE140020

Mr. Joe MeyerLos Rios Community College District3753 Bradview DriveSacramento, California 95827

Subject: Geotechnical InvestigationAmerican River College Athletic Fields4700 College Oak DriveSacramento, California

Dear Mr. Meyer:

The following report presents the findings and conclusions of our geotechnicalinvestigation conducted at the subject site. The purpose of the report was to providegeotechnical recommendations for site grading, shallow & deep foundations, floor slabs,utility construction and retaining walls, as indicated in our revised proposal dated April 8,2014 and executed on May 15, 2014. Recommendations for this project have beenprovided in the body of the report. Coordination between our office and your gradingcontractor will help reduce the potential for soil related problems.

Key information regarding this geotechnical report is presented on the following page.This information sheet has been provided to aid you in assessing the limitations of thisgeotechnical investigation as well as to indicate when additional information from ouroffice may be required. We appreciate the opportunity of working with you on this projectand look forward to providing our services in the future. Please contact us if you haveany questions.

Sincerely,NEIL O. ANDERSON& ASSOCIATES, INC.

Ryan R. King, Project Engineer Robert E. Holmer, PrincipalLicensed Civil Engineer 77326 Licensed Geotechnical Engineer 2672

9-24-149-24-14


KEY INFORMATON REGARDING YOUR GEOTECHNICAL REPORT

The Applicability of Geotechnical Reports is Limited

Geotechnical reports are written to provide test results, observations, and professional opinionsregarding a specific site for a specific project. Reports are tailored to the client and are influencedby each client’s risk management strategies, economical constraints, and personal preferences.Since each report is a “custom fit” for a particular client, reports should not be transferred toanyone else without first consulting the geotechnical engineer.

Each geotechnical report considers only the construction information and site boundaries thatexisted at the time of the investigation. Modification of construction plans, such as a change inthe shape, size, weight, location, or intended use of a project, nullifies the recommendationscontained in the report, unless the geotechnical engineer indicates otherwise. A geotechnicalreport can not be used for an adjacent site. Time and money can often be saved by consultingwith the geotechnical engineer when circumstances change from those which existed when thereport was written.

Site Conditions Can Change

The conditions which existed at the time of a geotechnical investigation can change.Investigations can only report conditions at a particular time and place and no guarantee existsto ensure that recommendations will apply after natural or man made changes occur. Examplesof some possible changes include: earthquakes, floods, fluctuations in groundwater, constructionon or next to the site, and the addition or removal of soil. In addition, even the mere passing oftime can affect site conditions. Consult with the geotechnical engineer to verify site conditionshave not changed since the geotechnical report was completed.

Geotechnical Findings Are Comprised Primarily of Professional Opinions

Even if typical 6 inch borings were spaced 5 feet apart across an entire site (typical boreholespacings are on the order of at least 10’s or 100’s of feet apart), less than one percent of the soilor rock on the site would actually be explored. From this limited exploration, the geotechnicalengineer is called on to provide an opinion regarding the subsurface conditions across the site,provide appropriate foundation recommendations, and predict the response of subsurfacematerials to numerous scenarios using information from samples that may or may not berepresentative of the entire site. Obviously, most of the geotechnical report is based on theprofessional opinion of the geotechnical engineer. The actual subsurface conditions maysignificantly differ from those which were encountered during the geotechnical investigation.Consequently, the most effective method of managing the risks associated with a project is toretain the geotechnical engineer who provided the report throughout construction of the project.

Contact Your Geotechnical Engineer When in Doubt

Time, money, and confusion can all be saved by simple explanations at critical moments. Pleasecontact your geotechnical engineer whenever there is any doubt regarding subsurface conditionsor their effect on part or all of any project.


GEOTECHNICAL INVESTIGATIONAMERICAN RIVER COLLEGE ATHLETIC FIELDS

SACRAMENTO, CALIFORNIA

TABLE OF CONTENTS

1.0 INTRODUCTION ............................................................................................. 12.0 SUMMARY OF CONCLUSIONS .......................................................................... 13.0 PREVIOUS INVESTIGATIONS ........................................................................... 24.0 GENERAL (SURFICIAL) SITE CONDITIONS ....................................................... 25.0 GENERAL GEOLOGIC CONDITIONS .................................................................. 26.0 FIELD EXPLORATION AND LABORATORY TESTING ........................................... 37.0 SOIL CONDITIONS .......................................................................................... 48.0 GROUND WATER ............................................................................................ 59.0 DESIGN STUDIES AND RECOMMENDATIONS .................................................... 5

9.1 Site Grading for Natural Turf and the Hammer Throw Diamond ............... 59.2 Site Grading for Artificial Turf – Competition Soccer Field ........................ 69.3 Grading Recommendations – Building Pads ............................................ 69.4 Exterior Walkways & Concrete Flatwork .................................................. 79.5 Shallow Foundation Recommendations ................................................... 79.6 Drilled Pier Foundation .......................................................................... 79.7 Building Slabs ....................................................................................... 89.8 Retaining/Screen Walls .......................................................................... 99.9 Drainage ............................................................................................ 109.10 Excavation .......................................................................................... 109.11 Testing, Inspections and Review .......................................................... 10

10.0 EVALUATION FOR SOIL CORROSIVITY ........................................................... 1111.0 PAVEMENT RECOMMENDATIONS ................................................................... 1212.0 UTILITY CONSTRUCTION .............................................................................. 1513.0 LIMITATIONS ............................................................................................... 15

Location Map ............................................................................................. Plate No. 1Test Boring Logs .................................................................................. Plate Nos. 2 - 9Test Boring Legend ...................................................................................Plate No. 10

APPENDIX A Engineered Fill Specifications

APPENDIX B Laboratory Testing

Revised January 27, 2015


GEOTECHNICAL INVESTIGATIONAMERICAN RIVER COLLEGE ATHLETIC FIELDS

4700 COLLEGE OAK DRIVESACRAMENTO, CALIFORNIA

OUR PROJECT NUMBER: SGE140020

1.0 INTRODUCTION

This report presents the findings, conclusions, and recommendations of a geotechnicalinvestigation conducted for the new athletic fields to be constructed on the campus ofAmerican River College located at 4700 College Oak Drive in Sacramento, California. TheAmerican River College Athletic Fields project will consist of construction of new soccerand football practice fields, a new hammer throw diamond, and a new competition soccerfield. The new competition soccer field will include spectator bleachers, rest rooms, aticket kiosk, and concession buildings. The competition soccer field will be synthetic turfand the practice fields will be natural grass turf. One row of additional parking will beconstructed along the west side of the project. Minor revisions to the adjacent parkinglot will also be completed. The development will include new concrete flatwork, pavementsections and associated landscaping. The site is currently landscaped with grass lawn.

The geotechnical study conducted at this site was prepared for the use of the architectand engineer for application to the design of the building and grading plans in accordancewith generally accepted geotechnical engineering practices. No warranty is expressed orimplied. This report presents the results of this study.

2.0 SUMMARY OF CONCLUSIONS

1. The soils encountered during our field exploration were fairly consistentbetween borings. The upper soils at the site generally consisted of mediumdense to dense, silty to clayey sand, underlain by yellowish brown, mediumdense to dense, poorly to well graded sand with variable silt, which was, inturn, underlain by sandy silts and lean clays to the maximum depth exploredof 31 feet. Groundwater was not encountered in any of the test borings atthe time of our exploration.

2. We recommend the proposed buildings, including the restroom, ticket kiosk,bleachers, and concession building be founded on spread footings foundedon the upper native soils. Detailed design and construction criteria arepresented in this report.

3. Good surface drainage should be constructed to provide rapid removal ofrunoff away from the buildings.

ARC Athletic FieldsOur Project Number: SGE140020Revised January 27, 2015

Page 2 of 16


3.0 PREVIOUS INVESTIGATIONS

Our office has performed several geotechnical investigations for other projects on theAmerican River College Campus. Prior to publication of this report, we have reviewed thefollowing projects:

1. ARC Swimming Pool & Fire Lane (Project No. SGG-0037), report dated July18, 2007.

2. ARC Life Science & Fine Arts Building (Project No. SGE10-0005), reportdated March 22, 2010.

3. ARC Parking Structure (Project No. SGE10-0038), report dated December6, 2010.

4. ARC Student Services Building Addition (Project No. SGE130013, reportdated August 9, 2013.

4.0 GENERAL (SURFICIAL) SITE CONDITIONS

At the time of our exploration, the site was landscaped with a grass lawn. The projectarea included numerous manicured lawn areas with portable goal nets and a hammerthrow diamond. The project is located at the southeastern portion of the American RiverCollege (ARC) campus. The site was bordered to the south by a softball and baseballdiamond followed by the American River College football stadium and associated parkinglot, to the west by an asphalt paved parking and drive area followed by the AmericanRiver College recreational facility, to the north by a berm/levee followed by agriculturalfields and small buildings, and to the east by Arcade Creek followed by residences andWinding Way.

5.0 GENERAL GEOLOGIC CONDITIONS

The project area is situated within the Great Valley geomorphic province of California. Ageologic map1 of the area was reviewed and indicated the surface soils underlying thesite are considered to be lacustrian deposits consisting of sands, silts, and gravels of theTurlock Lake Formation (Qtl). According to the referenced map, the sediments are lateQuaternary in age (2.6 million years ago and present). The total thickness of the lacustriansediments at this location was not determined during our exploration.

The closest active fault with a Maximum Moment Magnitude of 6.2 and a slip rate of 5.0millimeter per year is the Concord - Green Valley fault located a distance of 77 kilometersfrom the site. A significantly more active fault with a Maximum Moment Magnitude of7.1 and a slip rate of 6 millimeters per year is the Bartlett Springs fault located a distance

1 Wagner, D.L., 1981, Geologic Map of the Sacramento Quadrangle, California: California GeologicalSurvey, Scale 1:250,000


Page 3 of 16


of 107 kilometers from the site. The Foothills Fault system is located 20 kilometers fromthe site with a Maximum Moment Magnitude of 6.5 and a minimal slip rate of 0.05millimeters per year. This system is thought to have the potential of generating anearthquake but the probability of the site experiencing ground motions from an Alquist-Priolo fault is much higher. Consequently, these faults were used in our analysis inaccordance with acceptable geotechnical practices for the area.

Following is a table of the 2013 California Building Code (CBC) Soil Parameters 2 whichmay be used for design of structures at the subject site:

Table 1.2013 California Building Code Seismic Design Parameters

Site Class DMapped Spectral Acceleration Value of Rock (Short Period), SS 0.554gMapped Spectral Acceleration Value of Rock (1-Second Period), S1 0.263gSite (Amplification) Coefficient, Fa 1.357Site (Amplification) Coefficient, Fv 1.873Maximum Considered Earthquake/Site Modified (MCE) SpectralResponse Acceleration Value (Short Period), SMS

0.752g

Maximum Considered Earthquake/Site Modified (MCE) SpectralResponse Acceleration Value (1-Second Period), SM1

0.493g

Design Spectral Acceleration Value (Short Period), SDS 0.501gDesign Spectral Acceleration Value (1-Second Period), SD1 0.329gPGAM (Peak Ground Acceleration adjusted for Site Class effects) 0.263g

A site latitude and longitude of 38.6487° and -121.3441° were utilized in conjunction withthe tools provided by United States Geologic Survey web site. Based on the soil lithology,the relatively low potential ground accelerations, the age of the geologic setting, theabsence of ground water in the upper 50 feet (See Section 8.0 of this report), and ourreview of the liquefaction analysis performed in the ARC Parking Structure GeotechnicalInvestigation referred in Section 3 of this report, the probability of liquefaction inducedground distress to occur is considered to be very low.

6.0 FIELD EXPLORATION AND LABORATORY TESTING

The field exploration conducted at this site consisted of drilling eight (8) exploratory testborings carried to a maximum depth of 31 feet. The test borings were drilled with amobile B-24 drill rig, utilizing 4-inch solid flight augers. The locations of the test boringsare on the Location Map, Plate No. 1. The locations of the test borings were determinedby pacing from existing site features; hence, accuracy can be implied only to the degreethat this method warrants.

2 http://earthquake.usgs.gov/designmaps/us/application.php


Page 4 of 16


Sampling of the drilled test borings was performed at various depths using a CaliforniaModified 2.5 inch o.d. split spoon sampler with stainless steel tube liners. The samplerwas driven by a 140 pound hammer with a 30-inch drop. Blow counts required to drivethe sampler every 6 inches for a total of 18 inches were recorded.

Soil samples obtained from the test borings were preserved in stainless steel tubes untilthe samples could be tested in the laboratory. Samples were taken to the laboratory ofNeil O. Anderson & Associates, Inc., Sacramento, California and used for performingvarious laboratory tests. Tests performed consisted of unit weights, moisture content,Atterberg Limits, sieve analyses, and the percentage passing the U.S. No. 200 sieve. Theunconfined compression strengths shown on the Log of Test Boring sheets weremeasured with Pocket Penetrometers in the laboratory. A summary of the test resultsare presented on the Log of Boring sheets, Plates 2 through 9.

7.0 SOIL CONDITIONS

Visual classification of each soil stratum encountered according to ASTM D2488 (Visual –Manual Procedure) was made in the field by a representative from our office at the timethe test borings were drilled. The samples obtained were checked in the laboratory byan engineer and classification verified according to ASTM D2487. A classification andgraphical representation of each soil encountered is presented on the Log of Boringsheets. The test boring legend is presented on Plate No. 10.

The soils encountered during our field exploration were fairly consistent between borings.The upper soils at the site generally consisted of medium dense to dense silty to clayeysand, underlain by yellowish brown, medium dense to dense poorly to well graded sandwith variable silt, which was in turn underlain by sandy silts and lean clays to themaximum depth explored of 31 feet. For a more detailed description of the soilsencountered in the test borings see the Logs of Test Boring sheets.

Test boring logs show subsurface conditions at the date and location indicated and it isnot warranted that they are representative of subsurface conditions at other locationsand times.

One sample of near surface sandy silt was tested in our laboratory for Atterberg limitsand exhibited a liquid limit of 20, a plasticity index of 3, and contained 59 percent silt andclay-sized particles (passing the No. 200 sieve). One sample of near surface silty sandwas tested in our laboratory for Atterberg limits and exhibited a liquid limit of 19, aplasticity index of 2, and contained 35 percent silt and clay-sized particles (passing theNo. 200 sieve). One sample of near surface clayey sand was tested in our laboratory forAtterberg limits and exhibited a liquid limit of 37, a plasticity index of 19, and contained30 percent silt and clay-sized particles (passing the No. 200 sieve). Two underlyingsamples of sandy lean clay were tested in our laboratory for Atterberg limits and exhibited


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liquid limits of 27 and 32, plasticity index of 12 and 10, and contained 55 and 71 percentsilt and clay-sized particles (passing the No. 200 sieve). One sample of poorly gradedsand was tested for sieve analysis and contained 2 percent silt and clay sized particles(passing the No. 200 sieve) with a coefficient of uniformity (Cu) equal to 3.3 and acoefficient of curvature (Cc) equal to 1.3. One sample of gravelly well graded sand wastested for sieve analysis and contained 1 percent silt and clay sized particles (passing theNo. 200 sieve) with a coefficient of uniformity (Cu) equal to 6.1 and a coefficient ofcurvature (Cc) equal to 1.1.

Expansive Soils:

As previously described, the surface soils consist of silty to clayey sands. Three samplesof near surface soils were tested in our laboratory for Atterberg limits. Laboratory testingindicates the soils at this site exhibit low plasticity and are likewise considered to havelow expansion potential.

8.0 GROUND WATER

Ground water was not encountered in any of our borings at the time the borings weredrilled. However, the ground water data library was reviewed for the surrounding area(http://www.water.ca.gov/waterdatalibrary/). Ground water Level Data for Well386635N1213486W001 which is approximately 1.1 miles north of the site depictedground water to be measured at a depth of approximately 141 feet below surroundinggrade (measurement taken 3-28-2014). Groundwater conditions in the future couldchange due to rainfall, construction activities, irrigation, or other factors. The evaluationof these factors is beyond the scope of this study.

9.0 DESIGN STUDIES AND RECOMMENDATIONS

From a soil engineering standpoint, our office concludes that the site is suitable forconstruction of the proposed buildings & improvements; however, all of the conclusionsand recommendations presented in this report should be incorporated into the designand construction to help reduce the potential for soil and foundation problems.

9.1 Site Grading for Natural Turf and the Hammer Throw Diamond

Areas to be graded for construction of natural turf fields should initially be cleared of allsurface organic growth, loose organic soil, and miscellaneous debris. After clearing, theresulting subgrade should be scarified to a minimum depth of 12 inches; moistureconditioned, and re-compacted as specified in Appendix A, Engineered Fill Specifications.

After scarification and re-compaction of the subgrade, any required fills should be placedand compacted as engineered fill as specified in Appendix A. After the turf fields have


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been rough graded, the turf field and any specified drainage underlayment and geotextilefabric, should be placed and constructed in accordance with the specifications of thelandscape architect. Any gravel sub drains constructed shall be wrapped in filter fabric(Mirafi 140N or equivalent). A representative of our firm should be present duringconstruction to observe site grading and test compaction.

9.2 Site Grading for Artificial Turf – Competition Soccer Field

The competition soccer field is planned to have an artificial turf. The surficial sand andsilty soils are loose and can yield under normal athletic use. The artificial turf plannedfor construction of the competition soccer field is very sensitive to post constructionyielding or other movement. As a result, the near surface soils are judged to beunsuitable for artificial turf construction. In order to provide a stable surface for artificialturf construction, and reduce post construction soil related movement, we recommendthe surficial soils at the artificial turf field be chemically treated with cement.

The soccer stadium field should be graded and constructed with moisture-conditionedon-site soils as indicated in Section 9.1. Once the field is brought to grade, the upper 12inches is thoroughly mixed to a depth of 12 inches with a minimum spread rate of 5.0pounds per square foot of Portland type II cement. Cement treated subgrade shall becompacted to at least 95% of the Cal Trans Test Method 231 or 312. Cement treatmentshould be performed according to Section 27 of the Cal Trans Standard Specifications,latest edition. Special emphasis shall be given to the requirement to cover or seal thecement treated soil within 24 hours after completion of treatment to protect the treatedsoil during curing. The treatment should extend at least 5 feet beyond the field andunder any perimeter athletic tracks, sidewalks, or other hardscape.

The cement treated subgrade shall be covered with a layer of filter fabric, such as MirafiN-series. At least 6 inches of permeable drain rock shall be placed immediately beneaththe synthetic turf, over the filter fabric. Specifications for the drain rock material shall beprovided by the Architect. Any gravel subdrains shall be wrapped in filter fabric. Thelandscape architect should be informed that plants will not grow in cement-treated soil.A representative of our firm should be present during grading and limetreatment to observe site grading and test compaction.

9.3 Grading Recommendations – Building Pads

This project will include construction of several support buildings which may includeconcession stand, ticket kiosk, restrooms, spectator bleachers, and/or maintenancebuildings. After the building pads have been cleared, the subgrade should then bescarified to a minimum depth of 12 inches and compacted to a minimum 90 percentrelative compaction, at approximately optimum moisture content asdetermined by the ASTM D1557 test method. If the above requirements are notmet, the fill or compacted subgrade will be considered unacceptable and reworking of


Page 7 of 16


the fill or subgrade shall be required. Engineered fill should extend a minimum of fivefeet beyond proposed foundation lines or under any perimeter sidewalks or other exteriorconcrete flatwork. A representative of our office should be present duringconstruction to observe site grading and test compaction.

9.4 Exterior Walkways & Concrete Flatwork

Subgrade soils supporting exterior concrete or asphalt flatwork, shall be prepared inaccordance with Section 9.2 – Grading Recommendations. We recommend the concretewalkways and flatwork to be at least 5 inches thick and be reinforced with #3 bars spacedat 18 inches on center each way. At least 6 inches of Caltrans Class 2 aggregate baseshall be placed beneath the flatwork. If the subgrade soil supporting the sidewalk hasbeen cement treated, then the aggregate based section may be reduced to 4 inches.Aggregate base shall be compacted to at least 95% relative compaction.

9.5 Shallow Foundation Recommendations

If grading is accomplished as specified, foundations for the proposed buildings mayconsist of shallow, spread footings bearing directly on undisturbed native soil. Thebuilding structure foundation should be embedded a minimum depth of 15 inches belownearest surrounding grade. Minimum footing depth does not include gravel, aggregatebase, or other slab underlayment. The structure foundation bearing on undisturbednative sandy soils may be designed using a bearing capacity of 1,500 pounds per squarefoot (psf), for dead plus live loads. Bearing capacity may be increased by 1/3 fortemporary wind and seismic loads.

Potential settlement, either immediate or long term, of foundations constructed onundisturbed native sandy soils and loaded in the manner described above, should be lessthan 1 inch total and ½ inch differential across the width of the buildings. Care shouldbe taken to understand settlements may vary based on actual loads and footing sizes.

Lateral resistance for footing foundations may be provided by assuming a passivepressure acting against the side of the footings equal to 300 pounds per cubic foot (pcf)equivalent fluid pressure. Lateral resistance may also be provided by computing frictionbetween the bottom of the footing and the soil. A coefficient of friction of 0.35 shouldbe utilized. If footings are cast against firm native soil, passive and frictional resistancemay be combined but the passive resistance should be reduced by 50 percent.

9.6 Drilled Pier Foundation

The project may include overhead lighting or other pole supported structures.Foundations for these elements may consist of either a spread footing foundation or astraight shaft drilled friction pier foundation. Footing foundations should be designed in


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accordance with the criteria specified in section 9.4 of this report. If a drilled pierfoundation is desired, the piers should be designed with the following criteria:

1. Piers should be designed as a friction pier using an allowable skin frictionvalue of 400 pounds per square foot (psf) for the portion of the pierembedded in the native subgrade. Skin friction should be neglected for thetop 3.0 feet of pier. Skin friction may be increased by 1/3 for temporarywind and seismic loads. Lateral loads to the pier can be resisted bycomputing a passive pressure equal to 300 pound per cubic foot (pcf)equivalent fluid pressure (EFP) acting against a projected area equal to 1.5times the pier diameter. The top 3.0 feet should be ignored whencomputing passive resistance. Uplift capacity of the drilled pier should betaken as ¾ of the calculated downward vertical capacity.

2. Pier should have a minimum length of at least 6 feet and a minimumdiameter of 16 inches.

3. Concrete should be placed immediately after the hole is drilled, cleaned andinspected utilizing a "drill and pour" procedure to avoid possiblecontamination of the open pier hole. Concrete should not be placed in pierholes with more than 4” of water. If drilling problems occur, we should becontacted to discuss alternatives with the structural engineer.

4. Formation of mushrooms or enlargements at the top of pier should beavoided during pier drilling. If mushrooms develop at the top of the pierduring drilling, sono-tube should be placed at the pier top to help isolatethe pier.

5. Pier excavation should be observed by a representative of our office toverify that suitable depth and bearing material has been encountered

9.7 Building Slabs

Slab on grade floors that will not be covered with moisture sensitive flooring, such aswood or vinyl, shall be underlain by a 6-inch thick layer of Cal Trans Class 2 aggregatebase that is compacted to at least 95% of maximum density as determined by ASTMD1557. Our office recommends the floor slab thickness and reinforcing design bedetermined by the project structural engineer.

Moisture transmission through concrete slab-on-grade floors has been known to causedelamination, warping and other damage to floor coverings. Wood and vinyl flooringsare particularly susceptible to damage. Neil O. Anderson and Associates does not professto be experts in moisture proofing concrete slabs-on-grade, and our firm knows of noconstruction method that will completely eliminate the risk of damage. In order to providesome level of protection against damage, it is common practice in this area to place acapillary break and a vapor retardant layer beneath the slab.


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There are additional measures that may be incorporated to further reduce, but noteliminate, the risk. Some (but not all) of these measures include: using concrete with awater-cement ratio of 0.45 or less, employing a qualified testing laboratory to providematerials testing and quality control during concrete placement and curing, using topicalconcrete sealers, installing water stops at cold joints between the foundation capillarybreak and slab on grade, sealing the vapor retarder where plumbing penetrations occur,limiting the use of vinyl and wood flooring, and testing the concrete slab for moisturetransmission rates immediately prior to placement of floor coverings. These measuresmay be considered if additional protection is desired.

The following recommendations are commonly used in this area and we believe thesemeasures should be incorporated to provide a minimum level of protection againstdamage if moisture vapor transmission is critical to the project.

Floor Slab Minimum Recommendations:

Four inches of clean ¾ inch gravel should be placed between the slab and the engineeredfill. The gravel should be covered by an impervious vapor retarder such as 10 mil sheetvinyl or equivalent. The vapor retarder should be continuous and lapped a minimum of2 feet and draped down the side of the footings at least 1 foot. The vapor retarder shouldbe covered by 2 inches of sand to protect it during construction and to aid in curing theconcrete. This sand should meet the requirements of ACI 302.1R. However, we knowfrom experience that most local sand will not meet these requirements. In our opinion,the sand should be a sand or silty sand containing no more than 20 percent passing theNo. 200 sieve. Alternative materials must be approved by the geotechnical engineer priorto being brought to the site.

The sand should be moist but not saturated at the time of concrete placement. If thesand is saturated or free water is visible, the concrete should not be placed until the sandis dried sufficiently to only be moist or is replaced. If construction will take place inwinter, sand may be substituted with inch pea gravel. The pea gravel may not besaturated. Free water must not be visible on the gravel. If the gravel is saturated, itmust be dried sufficiently to only be moist or be replaced prior to placement of concrete.

Our office recommends the floor slab thickness and reinforcing design be determined bythe project structural engineer. Exterior finish grades should be below the floor subgradelevel unless special drainage and waterproofing features are employed to reduce thepotential for moisture migration under the slab.

9.8 Retaining/Screen Walls

Site retaining walls may be constructed. Retaining walls will be subject to lateral earthpressures. Site retaining walls may be supported by a spread footing type foundationdesigned using the same parameters provided in Section 9.4 of this report.


Page 10 of 16


The lateral earth pressure on a retaining wall depends on the height of the wall, type ofbackfill, slope of the backfill surface, and allowable horizontal movement on top of thewall. A calculated at-rest earth pressure of 55 pcf equivalent fluid density should be usedfor retaining walls which are restrained from rotating at the top. A calculated active earthpressure of 45 pcf equivalent fluid density should be used for site retaining walls whichare allowed to rotate at the top. The above active earth pressure assumes the retainingwall will support a backslope no steeper than 5:1 (H:V). We have assumed the backfillwill be the on-site non-expansive soils. For lateral load resistance, footings may bedesigned with a passive earth pressure of 300 pcf. Equivalent fluid densities do not includeallowances for surcharge loads or hydrostatic pressures. The hydrostatic pressure on theretaining walls should be relieved using drains behind the walls connected to tight lines.

9.9 Drainage

Special care should be taken to ensure adequate drainage is provided throughout the lifeof the structures. Properly designed and constructed foundations can be seriouslydamaged by neglecting to install and regularly verify performance of recommendeddrainage systems. Appropriate down spout extensions from roof drainage should fall onsplash blocks a minimum of 2 feet from the structure to be connected to tight lines thatdrain away from the buildings. Any flatwork adjacent to the buildings should slope aminimum of 1 percent for a distance of 8 to 10 feet beyond the building perimeters. Ifthis grade is unable to be obtained, proper drainage inlets will need to be placed to carrysurface water away from the foundations.

Care should be taken to ensure that landscaping is not excessively irrigated and to ensurethat landscaping drains away from the structures. Implementation of adequate drainagefor this project can affect the surrounding developments. Consequently in addition todesigning and constructing drainage for the subject site, the effects of site drainage mustbe taken into consideration for surrounding sites.

9.10 Excavation

As indicated previously, sands and silts were encountered in our test borings.Consequently, conventional excavating equipment may be utilized on this site. Thecontractor should plan his work accordingly.

9.11 Testing, Inspections and Review

Our office should be afforded the opportunity of reviewing the completed foundation andgrading plans to verify that our recommendations have been properly interpreted andincorporated. Unless our office is allowed this opportunity, we disavow any responsibility


Page 11 of 16


from problems arising from failure to follow geotechnical recommendations or improperinterpretation and implementation of our recommendations.

Our office should be retained to perform the recommended foundation inspections,grading observations and compaction testing. As indicated, the building pad shall betested for compaction as per the requirements specified in Appendix A of this report.Unless we have been retained to provide these services, our office cannot be heldresponsible for problems arising during or after construction that could have been avoidedhad these services been performed. The fees for these services are in addition to thatassociated with this report.

10.0 EVALUATION FOR SOIL CORROSIVITY

Neil O. Anderson & Associates, Inc., a Terracon Company does not profess to be corrosionengineers. We are providing the following information for use by the design engineer. Acompetent corrosion engineer should be consulted to determine the necessarycorrosion/cathodic protection for the proposed concrete and underground utilities and ifadditional testing is warranted.

Two soil samples were submitted to Terracon Chemical Laboratory in Las Vegas, Nevadafor testing. The tests performed on this sample included pH, resistivity, sulfateconcentration, chloride concentration, and Red-Ox. The results of these tests arepresented below. The test results from the laboratory are included in Appendix C,Laboratory Testing.

Table 2.

BoringID

Depth,ft. pH Resistivity,

ohm-cmSulfate

concentration,mg/kg

Chlorideconcentration,

mg/kgB2 5 8.11 4365 69 50B6 2.5 6.67 2200 83 75

According to the ACI Code 318, Sections 4.3, sulfate concentrations between 0 ppm to150 ppm are considered negligible. The sulfate tests resulted in negligible values.Furthermore, ACI does not specify a specific cement type, a maximum water-cementratio, or minimum compressive strength for concrete exposed to negligible sulfateexposure. For further information see the ACI Code 318, Sections 4.3 and 4.4.The results for resistivity were 2200 to 4365 ohm-cm. Testing indicates the soils arehighly corrosive to highly corrosive towards buried ferrous metals. A generally acceptedcorrelation between soil resistivity and corrosivity towards buried ferrous metals isprovided below3:

3 Roberge, Pierre R., Corrosive Basics: An Introduction of, 2nd Edition, 2006.


Page 12 of 16


Table 3.Minimum Resistivity, ohm-cm Corrosion Potential

Greater than 20,000 Essentially non-corrosive10,000-20,000 Mildly corrosive5,000-10,000 Moderately corrosive3,000-5,000 Corrosive1,000-3,000 Highly corrosive

Less than 1,000 Extremely corrosive

In general, sandy soils are fairly resistant while clay soils, especially those contaminatedwith saline water, are extremely corrosive. These test results are only an indication ofthe corrosive potential of the soils encountered in our test borings at the depths indicatedunder saturated conditions as determined by ASTM G-57. Since soils are not likely to bein a saturated condition minimum resistivity will likely be higher than what was tested inour laboratory. Other factors that affect the life of buried metals are the pH of the soiland whether the soils will be saturated or dry. In general, soils high in pH and low inmoisture tend to be less corrosive. Other soils present on the site may produce widelyvarying test results.

As indicated, a competent corrosion engineer should be consulted to determine thenecessary corrosion/cathodic protection for the proposed concrete and undergroundutilities and if additional testing is warranted. Laboratory test results are included onPlate 10.

11.0 PAVEMENT RECOMMENDATIONS

The parking lot and drive aisle at the west side of the field’s project are planned fordemolition and reconstruction. Based on our experience on this campus, we anticipatethe subgrade soils beneath the existing pavement sections will be very wet and pumpunder the loading of heavy equipment. As a result, we recommend the contractor includecement treatment of the pavement subgrade as an alternate line item in the biddingprocess.

Cement treatment involves treating the pavement subgrade soils with a certainpercentage of cement, usually 3 to 5 percent based on the dry unit weight of the soil, fora depth of 12 to 18 inches. For estimating purposes, a spread rate of about 5.0 poundsper square foot may be used for a 12 inch mixing depth and 7.5 pounds per square footfor an 18 inch mixing depth. The determination of the amount of cement to be usedneeds to be determined in the field at the time of grading. Cement treatment isperformed after rough grading of the pavement areas is completed. Recommendationsfor both conventional and cement treated pavement sections are presented below.


Page 13 of 16


Traffic indices of 3.5, 5.0, and 7.0 were used to design the pavement sections for thesite. The project civil engineer should be afforded the opportunity of specifyingthe most appropriate traffic index for the proposed traffic and usage. If adifferent traffic index is desired or required, please contact our office and a suitablerecommended design can be provided. Flexible (asphalt) pavement sections have beendesigned according to the latest addition of the Cal Trans Highway design manual andusing a 20-year pavement life. The pavement sections designs are shown below.

Table 4.FLEXIBLE PAVEMENT SECTION DESIGN

SubgradeR-Value

TrafficIndex Traffic

Pavement Section, inches

Asphalt Concrete AggregateBase

6 3.5 Auto Parking Spaces –Pedestrian Sidewalks 2.5 6.0

6 5.0 Auto Drives 3.0 9.56 7.0 Truck Drive or Fire Lane 4.0 15.5

The recommended concrete pavement sections have been designed utilizing the PortlandCement Associations manual "Thickness Design for Concrete Highway and StreetPavements". Design is based on a 20 year pavement life. The rigid pavement sectionsare presented next:

Table 5.RIGID (CONCRETE) PAVEMENT SECTION DESIGN

SubgradeStrength Traffic Pattern


ConcretePavement

CompressiveStrength, psi

AggregateBase

low 6 trucks per day 6.0 3000 4.0Note: 3/4 inch diameter by 16 inch smooth dowels spaced at 12 inches on center should be lightly greased and utilized atconstruction joints. Dowels should be cut not sheared. #3 bars at 18 inches on center may be utilized for shrinkage control,however, bars should not continue across construction or contraction joints. Reinforcement across joints restrains joints fromopening as the slab shrinks and expands during temperature fluctuations. 4 As an alternative to shrinkage reinforcement, fiberor steel mesh may be utilized. A rough finish of the concrete surface also helps to mask cracks. Contraction joints should have amaximum spacing of 12 feet on center.

The paving materials must conform to the requirements of the State of California,Department of Transportation, Standard Specifications, latest edition. Type B asphalt

4 ACI, Guide for concrete floor and Slab Construction, ACI 302.1R-96.


Page 14 of 16


concrete and class 2 aggregate base should be used. The cement treated pavementsections presented below are based on the following assumptions:

Cement treated subgrade soil will produce a minimum R-value of 50.Cement treated subgrade soil will produce a minimum unconfined compressivestrength of 200 pounds per square inch.Since it is not possible to compact the subgrade soil beneath the cement treatedportion, an additional 3 inches of cement treated soil has been added to thecalculated pavement section.Cement treated materials shall conform to the requirements in Section 27 of theCaltrans Standard Specifications, latest edition.

Table 6.CEMENT TREATED FLEXIBLE PAVEMENT SECTIONS

SubgradeR-Value

TrafficIndex Traffic


AsphaltConcrete

AggregateBase

CementTreated

Subgrade

50 3.5 Auto Parking Spaces –Pedestrian Sidewalks 2.5 3.0 12

50 5.0 Auto Drives 3.0 3.0 1250 7.0 Truck Drive/Fire Lane 4.0 4.0 12

As previously mentioned, for estimating purposes, a spread rate of about 5.0 pounds persquare foot may be used for a 12 inch mixing depth. The determination of the amountof cement to be used needs to be determined in the field at the time of gradingoperations. Cement treatment for the areas should be performed according to Section27 of the California Transportation Standard Specifications, latest edition. Thecement treated subgrade should be compacted to dry densities in excess of 95 percentof the maximum dry density obtainable in the ASTM D1557 Compaction Test.

The drive lanes and parking stalls that will be supported by the subgrade soils on theground floor of the garage should be graded in accordance with the following. Thepavement area should be stripped of all organic matter, loose soil, etc., and any requiredcuts or fills made. A minimum of 8 inches of compacted subgrade should be providedbeneath the pavement sections. The subgrade should be compacted to dry densities inexcess of 95 percent of the maximum dry density obtainable by the ASTM D1557 testmethod.

Studies have indicated that a major factor in extending pavement life is to provideadequate drainage for both the pavement surface and subgrade. Care should be madeduring the development of the grading plan to provide for good drainage. We recommendextruded curbs not be utilized for planters. Landscaped and irrigated planters that are


Page 15 of 16


constructed adjacent to pavement should have cut-off curbing constructed around themthat extends a minimum of 4 inches into the subgrade soil. We recommend rigid concretepavements in areas where heavy trucks, such as garbage trucks, will travel or make sharpturns. The above recommended pavement sections assume periodic maintenance, suchas crack sealing, etc., will be performed over the life of the pavements.

12.0 UTILITY CONSTRUCTION

Based on Occupational Safety and Health Standards, the soils encountered in our testborings classify as Type C (sands). Type C soils require a maximum slope of 1½:1(horizontal to vertical) for excavations less than 20 feet deep. The contractor shouldhave a competent person identify all soils encountered in excavation and refer to OSHAand Cal-OSHA standards to determine appropriate methods to protect individuals workingin excavations.

Backfill placed in trenches should be placed in approximately 8 inch lifts in uncompactedthickness. However, thicker lifts may be used, provided the method of compaction isapproved by the soil engineer and the required minimum degree of compaction isachieved. Material should be compacted to at least 90 percent of the maximum drydensity obtained by the ASTM D1557 test method. The upper 8 inches of trench backfillwithin pavement areas should be compacted to at least 95 percent relative compaction.

13.0 LIMITATIONS

The recommendations of this report are based on the information provided regarding theproposed construction as well as the subsoil conditions encountered at the test boringlocations. If the proposed construction is modified or re-sited, or if it is found duringconstruction that subsurface conditions differ from those described on the test boringlogs, the conclusions and recommendations of the report should be considered invalidunless the changes are reviewed and the conclusions and recommendations modified orapproved in writing.

The analysis, conclusions and recommendations contained in this report are based on thesite conditions as they existed at the time we drilled our test borings. It was assumedthat the test borings are representative of the subsurface conditions throughout the site.If there is a substantial lapse of time between the submission of our report and the startof the work at the site, or if conditions have changed due to natural causes or constructionoperations at or adjacent to the site, we urge that our report be reviewed to determinethe applicability of the conclusions and recommendations considering the changedconditions and time lapse. This report is applicable only for the project and site studied.This report should not be used after 3 years.

Our professional services were performed, our findings obtained, and ourrecommendations proposed in accordance with generally accepted engineering principles


Page 16 of 16


and practices. This warranty is in lieu of all other warranties either expressed or implied.Test findings and statements of professional opinion do not constitute a guarantee orwarranty, expressed or implied.

The scope of our services did not include any environmental assessment or investigationfor the presence or absence of wetlands, hazardous or toxic materials in the soil, surfacewater, groundwater or air, on or below or around this site. Any statements in this reportor on the soil logs regarding odors noted or unusual or suspicious items or conditionsobserved are strictly for the information of our client.

B-1

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BORINGLOCATIONMAPAMERICANRIVERCOLLEGEATHLETICFACILITIES

SACRAMENTO,CA958414700COLLEGEOAKDRIVE

SG

E14

0020

06/2

5/14

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VIC

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ADE

CR

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B-3

B-2

B-4

B-6

B-7

B-5

See report for description of fieldand laboratory procedures.

See Plate 10 for explanation of symbolsand abbreviations.

PLATE 2



PLATE 3



PLATE 4



PLATE 5



PLATE 6



PLATE 7



PLATE 8



PLATE 9

GENERAL NOTES

PLATE 12A

UNIFIED SOIL CLASSIFICATION SYSTEM

Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests ASoil Classification

GroupSymbol Group Name B

Coarse Grained Soils:More than 50% retainedon No. 200 sieve

Gravels:More than 50% ofcoarse fraction retainedon No. 4 sieve

Clean Gravels:Less than 5% fines C

Cu 4 and 1 Cc 3 E GW Well-graded gravel F

Cu 4 and/or 1 Cc 3 E GP Poorly graded gravel F

Gravels with Fines:More than 12% fines C

Fines classify as ML or MH GM Silty gravel F,G,H

Fines classify as CL or CH GC Clayey gravel F,G,H

Sands:50% or more of coarsefraction passes No. 4sieve

Clean Sands:Less than 5% fines D

Cu 6 and 1 Cc 3 E SW Well-graded sandCu 6 and/or 1 Cc 3 E SP Poorly graded sand

Sands with Fines:More than 12% fines D

Fines classify as ML or MH SM Silty sand G,H,I

Fines classify as CL or CH SC Clayey sand G,H,I

Fine-Grained Soils:50% or more passes theNo. 200 sieve

Silts and Clays:Liquid limit less than 50

Inorganic:PI 7 and plots on or above “A” line J CL Lean clay K,L,M

PI 4 or plots below “A” line J ML Silt K,L,M

Organic:Liquid limit - oven dried

0.75 OLOrganic clay K,L,M,N

Liquid limit - not dried Organic silt K,L,M,O

Silts and Clays:Liquid limit 50 or more

Inorganic:PI plots on or above “A” line CH Fat clay K,L,M

PI plots below “A” line MH Elastic Silt K,L,M

Organic:Liquid limit - oven dried

0.75 OHOrganic clay K,L,M,P

Liquid limit - not dried Organic silt K,L,M,Q

Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat

A Based on the material passing the 3-inch (75-mm) sieveB If field sample contained cobbles or boulders, or both, add “with cobbles

or boulders, or both” to group name.C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded

gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorlygraded gravel with silt, GP-GC poorly graded gravel with clay.

D Sands with 5 to 12% fines require dual symbols: SW-SM well-gradedsand with silt, SW-SC well-graded sand with clay, SP-SM poorly gradedsand with silt, SP-SC poorly graded sand with clay

E Cu = D60/D10 Cc =6010

230

DxD

)(D

F If soil contains 15% sand, add “with sand” to group name.G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.

H If fines are organic, add “with organic fines” to group name.I If soil contains 15% gravel, add “with gravel” to group name.J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay.K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,”

whichever is predominant.L If soil contains 30% plus No. 200 predominantly sand, add “sandy” to

group name.M If soil contains 30% plus No. 200, predominantly gravel, add

“gravelly” to group name.N PI 4 and plots on or above “A” line.O PI 4 or plots below “A” line.P PI plots on or above “A” line.Q PI plots below “A” line.

PLATE 12B

ARC Athletic FieldsOur Project Number: SGE140020Revised September 24, 2014


APPENDIX AEngineered Fill Specifications

SCOPEPrincipal items of work included in this section are as follows:

A. Cleaning and StripingB. Construction of Fill

A. CLEANING AND STRIPPING

Work includes cleaning and stripping of the building pad and surrounding area asindicated on the drawings. From this area remove all debris, irrigation lines, oldpavement, trees, brush, roots, and vegetable ruin and grub out all large roots (½ inch orgreater diameter) to a depth of at least two feet below the footing elevation. Thevegetable materials and all materials from the cleaning operation shall be removed fromthe site.

B. CONSTRUCTION OF FILL

1. Preliminary Operations

After the cleaning and stripping operation and the cuts have beencompleted and before any fill is placed in any particular area, the existingsurface shall be scarified to a depth of 12 inches and compacted to drydensities in excess of 90 percent of the maximum dry density as obtainedby the Standard Test Methods for Laboratory Compaction Characteristics ofSoil using Modified Effort, ASTM D1557 designation. The soil should becompacted at moisture contents between 1 and 3 percentage points abovethe optimum moisture content. It may be necessary to adjust the moisturecontent of the subgrade soil by watering or aeration, to bring the moisturecontent of the soil near optimum in order that the specified densities canbe obtained.

2. Source of Material

Engineered fill materials (on site or import) shall consist of sandy silts,sands, or sands and gravels unless stated otherwise in the report.Engineered fill material shall not contain rocks greater than 3 inches ingreatest dimension and should be non-expansive in nature with less than50% passing the No. 200 sieve and a plasticity index less than 12.



At least seven days prior to the placement of any fill, the engineer shall benotified of the source of materials. Samples of the proposed fill shall beobtained to determine the suitability of the materials for use as engineeredfill.

3. Placing and Compacting

Fill materials shall be spread in layers and shall have a uniform moisturecontent that will provide the specified dry density after compaction. Ifnecessary to obtain uniform distribution of moisture, water shall be addedto each layer by sprinkling and the soil disked, harrowed, or otherwisemanipulated after the water is added. The layers of the fill material shallnot exceed 8 inches and each layer shall be compacted with suitablecompaction equipment to provide the specified dry densities.

4. Required Densities

The dry density of the compacted earth shall be at least 90 percent of themaximum dry density obtainable by the ASTM D1557 test method. Theoptimum moisture content and maximum dry density will be determined bythe engineer and this information supplied to the contractor.

5. Seasonal Limits

No fill shall be placed during weather conditions which will alter the moisturecontent of the fill materials sufficiently to make adequate compactionimpossible. After placing operations have been stopped because of adverseweather conditions, no additional fill material shall be placed until the lastlayer compacted has been checked and found to be compacted to thespecified densities.

6. Control of Compaction

The density of the upper 6 inches of subgrade and of each layer of fill shallbe checked by the engineer after each layer has been compacted. Fielddensity tests shall be used to check the compaction of the fill materials.Sufficient tests shall be made on each layer by the engineer to assureadequate compaction throughout the entire area. If the dry densities arenot satisfactory, the contractor will be required to increase the weight ofthe roller, the number of passes of the roller, or manipulate the moisturecontent as required to produce the specified densities.



APPENDIX BLaboratory Testing

#007 (60c) X #074 (MED) #014 X #060 (#40) X#006 (110c) X #075 (SMALL) #192 (Pan) X

#173 #191#174 #S171 X

#S160 X

1 2 335 27 18VJ GH KE

14.75 14.59 14.7030.68 27.80 27.6528.06 25.59 25.382.62 2.21 2.27

13.31 11.00 10.6819.7 20.1 21.3

1 2JK 15

13.97 13.7016.67 16.8816.27 16.440.40 0.442.30 2.7417.4 16.1

2017

Project: 3

Technician:Soil Source:

Soil Information:

ATTERBERG LIMITS DETERMINATION, WASH #200 (ASTM D 4318)

LIQUID LIMITRun Number

Tare Number

Tare Number

Water (g)

Number of blows

Dry soil (g)

Tare (g)Wet soil + Tare (g)Dry soil + tare (g)

Liquid Limit Device Ground Glass Plate

EQUIPMENTOvens Splitter

Tested Date:

Tare (g)

Dry soil (g)Water Content (%)

Dry soil + tare (g)Water (g)

Wet soil + Tare (g)

Scales Sieves

Sampled Date:

Rick DoddsNative

Sample ID:Project Number:

Water Content (%)PLASTIC LIMIT WASH 200

Tare NumberTare (g)

Run Number

Dry Soil + Tare (g)Washed Soil + Tare (g)

Percent Passing

ML: Sandy Silt

Plastic Index:

6/4/20146/18/2014

ARC Athletic fieldsSGE140020

B1-1-I

Liquid Limit:Plastic Limit:

TJ214.5416.4296.8

59

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

10

Wat

erCo

nten

t(%

)

Number of Blows25

Plate B-1


#173 #191#174 #S171 X

#S160 X

1 2 334 21 26YZ KL BB

14.46 13.81 14.3826.32 25.92 28.6123.95 23.31 25.622.37 2.61 2.999.49 9.50 11.2425.0 27.5 26.6

1 2X 28

13.69 13.5018.74 18.3818.06 17.740.68 0.644.37 4.2415.6 15.1

2715

Project: 12


Soil Information:



Tare Number

Tare Number

Water (g)

Number of blows

Dry soil (g)




Tested Date:

Tare (g)



Wet soil + Tare (g)

Scales Sieves

Sampled Date:

Rick DoddsNative



Tare NumberTare (g)

Run Number


Percent Passing

CL: Sandy Lean Clay

Plastic Index:

6/4/20146/18/2014

ARC Athletic FieldsSGE140020

B1-2-I


kt235.7428

322.355

0.05.0

10.015.020.025.030.035.040.045.050.0

10

Wat

erCo

nten

t(%

)

Number of Blows25

Plate B-2


#173 #191#174 #S171 X

#S160 X

1 2 331 27 20FA ST UV

14.24 14.41 14.4827.08 26.48 26.5923.64 23.22 23.263.44 3.26 3.339.40 8.81 8.7836.6 37.0 37.9

1 2SX5 11

13.76 13.8319.47 18.7218.62 17.990.85 0.734.86 4.1617.5 17.5

3718

Project: 19


Soil Information:



Tare Number

Tare Number

Water (g)

Number of blows

Dry soil (g)




Tested Date:

Tare (g)



Wet soil + Tare (g)

Scales Sieves

Sampled Date:

Rick DoddsNative



Tare NumberTare (g)

Run Number


Percent Passing

SC: Clayey Sand

Plastic Index:

6/4/20146/18/2014


B3-1-I


SV240.2440.6380.8

30

0.0

10.0

20.0

30.0

40.0

50.0

60.0

10

Wat

erCo

nten

t(%

)

Number of Blows25

Plate B-3


#173 #191#174 #S171 X

#S160 X

1 2 330 24 13GI AA CD

13.81 14.38 14.6626.35 26.98 27.0624.37 24.92 24.971.98 2.06 2.09

10.56 10.54 10.3118.8 19.5 20.3

1 2A7 3M

13.82 13.6417.51 17.8516.99 17.250.52 0.603.17 3.6116.4 16.6

1917

Project: 2


Soil Information:



Tare Number

Tare Number

Water (g)

Number of blows

Dry soil (g)




Tested Date:

Tare (g)



Wet soil + Tare (g)

Scales Sieves

Sampled Date:

Rick DoddsNative



Tare NumberTare (g)

Run Number


Percent Passing

SM: Silty Sand

Plastic Index:

6/5/20146/18/2014


B6-1-I


RX243.8445.5374.9

35

0.0

5.0

10.0

15.0

20.0

25.0

30.0

10

Wat

erCo

nten

t(%

)

Number of Blows25

Plate B-4


#173 #191#174 #S171 X

#S160 X

1 2 329 22 14AB RO WX

14.76 13.69 14.7523.53 25.81 23.8721.42 22.84 21.612.11 2.97 2.266.66 9.15 6.8631.7 32.5 32.9

1 219 S

13.86 13.7217.40 18.5216.76 17.630.64 0.892.90 3.9122.1 22.8

3222

Project: 10


Soil Information:



Tare Number

Tare Number

Water (g)

Number of blows

Dry soil (g)




Tested Date:

Tare (g)



Wet soil + Tare (g)

Scales Sieves

Sampled Date:

Rick DoddsNative



Tare NumberTare (g)

Run Number


Percent Passing

CL: Lean Clay with Sand

Plastic Index:

6/5/20146/19/2014


B8-3-I


124.1341

187.471

0.05.0

10.015.020.025.030.035.040.045.0

10

Wat

erCo

nten

t(%

)

Number of Blows25

Plate B-5

JOB NAME: JOB NUMBER: SGE140020 DATE:

INFO: SAMPLE ID:

249

INCHES mm. MIN MAX3.00 76.2 3 in. 0 0 1002.00 50.8 2 in. 0 0 1001.50 38.1 1.5 in. 0 0 1001.00 25.4 1 in. 0 0 100

0.750 19.1 3/4 in. 0 0 1000.500 12.7 1/2 in. 0 0 1000.375 9.52 3/8 in. 0 0 1000.187 4.76 No. 4 0 0 1000.094 2.38 No.8 22 9 910.047 1.19 No. 16 55 22 780.023 0.59 No. 30 178 71 29

0.0117 0.297 No. 50 225 90 100.0059 0.149 No. 100 236 95 50.0029 0.074 No. 200 242.6 97.4 2.6

CLSLSE

CLSL

DUR

SIZE mmD60 2.86D50 2.08D30 1.23D10 0.46Cu 6.1Cc 1.1

NOTES:

TECHNICIAN: Nick Novotny

SPECIFIEDGRADING

LIMITS

TEST METHOD: CTM-202

Poorly -graded sand (SP)

SIEVE OPENINGS SIEVE SIZE ORNUMBER

ACCUMULATEDWT. RETAINED

TOTAL PERCENTRETAINED

PERCENTPASSING

DURABILITY

SE TEST

SIEVE ANALYSIS6/20/2014ARC Athletic Fields

TOTAL WEIGHT OF SAMPLE MINUS #4 MATERIAL WT.

B2-3-II

0102030405060708090

100

PERC

ENT

PASS

ING

SIEVE SIZE

PARTICLE GRADATION

200100503016841/2"1"2"

Plate B-6

JOB NAME: JOB NUMBER: SGE140020 DATE:

INFO: SAMPLE ID:

294

INCHES mm. MIN MAX3.00 76.2 3 in. 0 0 1002.00 50.8 2 in. 0 0 1001.50 38.1 1.5 in. 0 0 1001.00 25.4 1 in. 0 0 100

0.750 19.1 3/4 in. 0 0 1000.500 12.7 1/2 in. 40 14 860.375 9.52 3/8 in. 51 17 830.187 4.76 No. 4 82 28 720.094 2.38 No.8 125 43 570.047 1.19 No. 16 209 71 290.023 0.59 No. 30 255 87 13

0.0117 0.297 No. 50 275 94 60.0059 0.149 No. 100 285 97 30.0029 0.074 No. 200 291.0 99.0 1.0

CLSLSE

CLSL

DUR

SIZE mmD60 2.86D50 2.08D30 1.23D10 0.46Cu 6.1Cc 1.1

NOTES:

TECHNICIAN: Rick Dodds

SIEVE ANALYSIS6/20/2014ARC Athletic Fields

TOTAL WEIGHT OF SAMPLE MINUS #4 MATERIAL WT.

B7-2-II

SPECIFIEDGRADING

LIMITS

TEST METHOD: CTM-202

Well-graded Gravel (GW)

SIEVE OPENINGS SIEVE SIZE ORNUMBER

ACCUMULATEDWT. RETAINED

TOTAL PERCENTRETAINED

PERCENTPASSING

DURABILITY

SE TEST

0102030405060708090

100

PERC

ENT

PASS

ING

SIEVE SIZE

PARTICLE GRADATION

200100503016841/2"1"2"

Plate B-7

JOB NAME: JOB NUMBER: SGE140020 DATE: 6/20/2014 SAMPLE INFO: SAMPLE ID:

Sample ID Tare # Tare Wt (g)Tare + Dry Wt.

Before Wash (g)Tare + Dry Wt.After Wash (g)

Dry Wt. (g)Percent Passing

#200 (%)

B4-1-I K2 200.8 423.7 349 222.9 34

B5-2-I A4 54.3 252.8 200 198.5 27

TECHNICIAN: Rick Dodds TEST METHOD: ASTM D1140

Wash #200 (Soils)ARC Athletic Fields

Native

Plate B-8

Project Number:Service Date:Report Date:Task:

Client

Date Received:

B2-1-I B6-1-I

8.11 6.67

69 83

Nil Nil

426 577

+585 +646

50 75

4365 2200

Analyzed By:

The tests were performed in general accordance with applicable ASTM, AASHTO, or DOT test methods. This report is exclusively for the use of the clientindicated above and shall not be reproduced except in full without the written consent of our company. Test results transmitted herein are only applicable tothe actual samples tested at the location(s) referenced and are not necessarily indicative of the properties of other apparently similar or identical materials.

80145211

Terracon (80)Sample Submitted By: 6/26/2014

Results of Corrosivity Analysis

Chemist

06/27/14

Lab No.: 14-0343

Sample Number

Sample Location

Sample Depth (ft.)

06/27/14750 Pilot Road, Suite FLas Vegas, Nevada 89119(702) 597-9393

Project

CHEMICAL LABORATORY TEST REPORT

Kurt D. Ergun

pH Analysis, AWWA 4500 H

Water Soluble Sulfate (SO4), AWWA 4500 E(mg/kg)

Sulfides, AWWA 4500-S D, (mg/kg)

Total Salts, AWWA 2540, (mg/kg)

Red-Ox, AWWA 2580, (mV)

Chlorides, AWWA 3500 Cl B, (mg/kg)

Resistivity, ASTM G-57, (ohm-cm)

American River Athletic Fields

PLATE B-9

re: geotechnical letter american river college re … arc re-paving geotechnical...geotechnical...

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