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HomeMy WebLinkAboutCT 03-02; Carlsbad Ranch PA 5; Geotechnical Investigation; 2011-11-04RECORD COPY If i ilia 1 Oate GEOTECHNICAL INVESTIGATION Proposed Sales, Activity and Fitness Buildings Carlsbad Ranch, Planning Area 5 MarBrisa Phase II Carlsbad, Califomia Prepared For: Grand Pacific Resorts, Inc. 5900 Pasteur Court, Suite 200 Carlsbad, Califomia 92008 Prepared By: 3 MTGL, Inc. 6295 Ferris Square, Suite C San Diego, Califomia 92121 Project No. 1916-A08 Log No. 11-1409 CQ 3 0} DC < -J >- ,.:»!St.f.fj'C/- /.^•.fiafJ^^s%,;r^ Geotechnical Engineering Construction Inspecfion Materials Testing Environmentai Office Locations Orange County Corporate Branch: 2992 E, La Palma Avenue Suite A Anaheim, CA 92806 Tel: 714.632.2999 Fax: 714,632.2974 San Diego Imperial County 6295 Ferris Sqyare Suite C San Diego, CA 92121 Tel: 858,537.3999 Fax: 858,537.3990 Inland Empire 14467 Meridian Parkway Building 2A Riverside, CA 92518 TBI: 951,653.4999 Fax; 951.653,4666 Indio 44917 Go;f Center Parkway Suite 1 Indio, CA 92201 Tel: 760,342.4677 Fax: 760,342,4525 OC/LA/!nland Empire Dispatch 800.491.2990 San Oiego Dispatch 888,844,5060 wvvw.nntgllnc.com Project No. 1916-A08 Log No. 11-1409 November 4,2011 Grand Pacific Resorts, Inc. 5900 Pasteur Court, Suite 200 Carlsbad, Califomia 92008 Attention: Mr. Bmce Zelenka SUBJECT: Geotechnical Investigation Proposed Sales, Activity and Fitness Buildings Carlsbad Ranch, Planning Area 5 MarBrisa Phase II Carlsbad, California Dear Mr. Zelenka: In accordance with your request and authorization we have completed a geotechnical investigation at the site for a proposed Sales, Activity and Fitness Buildings including two Swimming Pools at the Carlsbad Ranch, Planning Area 5, MarBrisa Phase n in Carlsbad, CA. We are pleased to present the following report with our conclusions and recommendations. The site for proposed development is located inside the MarBrisa Resort that was previously graded with an elevated pad on the east comer with tennis court. Our report concludes that the proposed improvement and addition would be feasible provided the recommendations presented are incorporated into the plans and specifications. Details related to seismicity, geologic conditions, foundation design, and constmction considerations are included in subsequent sections of this report. We look forward to providing additional consulting services during the planning and constmction of the project. Sales, Activity & Fitness Buildings MarBrisa Resort. Carlsbad. CA Project No. 1916-A08 Lop No. 11-1409 If you have any questions regarding our report, please do not hesitate to contact this office. We appreciate this opportunity to be of service. Respectfully submitted, MTGL, Inc. \ Eduardo C. Dizon, RdlE ) Senior Engineer M.S. (Ben) Lo, RGE Chief Geotechnical Engineer Geoteclinical EiigiBeering Constructioii Inspectioii Materials Testing Envfroniiieiital Central Dispatch (8S8) 844-5060 Brandi Office .Salt Dk:p) I Imperhi! OHJisiies 6295 Ferris Square Sulk' C Sim Diego, Ca 9212! Tel: «58 537-.W9 Fiix: 858 5.^7-399(1 OiTiee LocalioiK • Orangt-/ !..-\ Ctiutitj • indiii » Los .Vnuek'H / Ventura County « Ri%'ersid€ / .Sail llernsirdiiK) Ctrufvin;!; AgeiicR-s fitak- of Caiifuriii'.i II..S.A O.SIii'l) Amcrirun As!.<!C. of SluU' ay> Cul 1 rail*. CCRI, Ciiiuctit & t,'(jiu:rct« Reffraicc i ulsoratsirj !.n<. Aogiiei L A Ci)smt.v LA CiSv MIA Ofasigc Ciiiiiit) Or;inm' Ci>im!.v lim ironii'.ciilal .MiiiiiiXemtiil AgCfKj .Sail Dicgo i:'n\ Sl> Water AiUlmrilv !nS;!iid Empiri' Cti.v of Riverside OMHSIV of Risersidi' December 9, 2011 Grand Pacific Resorts, Inc. Project No. 1916-B08 5900 Pasteur Court, Suite 200 Log No. 11-1452 Carlsbad, California 92008 Attention: Mr. Houston Arnold Subject: Percolation Test MarBrisa Phase II Carlsbad, California Dear Mr. Arnold: In accordance with your request and authorization, we have completed a percolation test at the Carlsbad Ranch, Planning Area 5, Marbrisa Resort Phase 2. The percolation test was performed at one location shown in the attached Figure-1. The test hole consist of 6-inch diameter and 48" deep with a 4" diameter perforated standpipe. Soil encountered in the test hole was visually classified. It consisted of approximately 18 inches of fill underlain by terrace deposit. The encountered soil generally consisted of silty clayey sand. Gravel was placed at the bottom and around the standpipe then the hole was filled completely with water for the pre-soaking phase ovemight. The following day, the test hole was again filled with water to let the soil rehydrate. Test hole was refilled with water after at least 20 minutes. Then the water drop at every 15 minutes was measured and at the same time the hole was refilled with water such that a minimum of 6 inches of water remains in the test hole. The test measurement was continued until the drop rates remain constant. The percolation rate was calculated based upon the last reading, a percolation rate of 27 minutes per inch. If you have any questions regarding this letter, please do not hesitate to contact our office. Respectfully submitted, MTGL, Inc. nrrln C Diznn. RCE Eduardo C. Dizon, RCE Senior Engineer Attachment: Figure 1 - Percolation Location Plan DRIVE r—fej Approximate Location of Percolation Test* PERCOLATION LOCATION PLAN MARBRISA RESORT, PHASE 2 Project No. 1916-B08 Date: DEC. 2011 FIGURE 1 Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa Resort. Carlsbad. CA Log No. 11-1409 TABLE OF CONTENTS INTRODUCTION 1 PROPOSED CONSTRUCTION 1 SCOPE 1 SITE DESCRIPTION 2 FIELD EXPLORATION 2 LABORATORY TESTING 3 GEOLOGY 3 REGIONAL GEOLOGY 3 LOCAL GEOLOGY 4 SITE GEOLOGIC CONDITIONS 4 Fill 4 Terrace Deposit 5 GROUNDWATER 5 DISCUSSION OF GEOLOGIC AND SEISMIC HAZARDS 5 FAULTING AND SEISMICITY 5 LIQUEFACTION POTENTIAL 6 LANDSLIDE, MUDFLOW AND FLOODING 6 GROUND RUPTURE O 6 SEISMIC SETTLEMENT 6 LATERAL SPREADING 7 TSUNAMIS AND SEICHES 7 SEISMIC DESIGN PARAMETERS 7 SUMMARY AND CONCLUSIONS 8 GENERAL CONSIDERATIONS 8 EXCAVATION CHARACTERISTICS 8 CUT/FILL TRANSITION CONDITIONS 8 EXPANSION POTENTIAL 8 CORROSIVITY 8 RECOMMEMDATIONS 9 GENERAL 9 SITE GRADING RECOMMENDATIONS 9 Site Preparation 9 Temporary Excavation 9 Site Grading 10 iii Sales, Activity & Fitness Buildings P^ojf No 1916-A08 MnrRrisa Resort. Carlsbad. CA Log No. 11-1409 General Compaction Standard ^' Import Fill Material j j FOUNDATION J,: LATERAL RESISTANCE SETTLEMENT |^ INTERIOR SLAB-ON-GRADE ^ EXTERIOR CONCRETE SLAB/FLATWORK ^ ^ RETAINING WALL |^ PRELIMINARY PAVEMENT 'Z CONSTRUCTION CONSIDERATIONS Moisture Sensitive SoilsAVeather Related Concems 15 Drainage and Groundwater Considerations 1^ Excavations Utility Trenches SITE DRAINAGE PLAN REVIEW GEOTECHNICAL OBSERVATION/TESTING 1' LIMITATIONS Figure 1 - Site Location Map Figure 2 - Boring Location Plan Appendix A - References Appendix B - Field Exploration Program Appendix C - Laboratory Testing Procedures Appendix D - Engineering Analysis Appendix E - General Earthwork and Grading Specifications IV Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa Resort. Carlsbad. CA Log No. 11-1409 INTRODUCTION In accordance with your request and authorization, MTGL, Inc. has completed a geotechnical investigation for the subject site. The following report presents our findings, conclusions and recommendations based on the results of our investigation, laboratory testing and engineering review. PROPOSED CONSTRUCTION A sales building of two to three-story with basement is planned on elevated pad with existing tennis court. Planned grading for the basement level consists of the removal of approximately 12 feet of the existing soil. In addition, site grading is to include the re-constmction of the elevated pad slopes to enlarge the existing pad area. The activity and fitness buildings including associated two swimming pools are to be constmcted west of the sales building. It is our understanding that the activity and fitness buildings are to include a basement level. Additional related improvements include paved driveway and parking, flatworks, and underground utilities. Future thirteen two- to three-story villas with paved parking are planned around the swinuning pools. SCOPE The scope of our Geotechnical services included the following: • Geotechnical investigation consisting of drilling six borings to explore subsurface conditions and to obtain samples for laboratory testing. (See Geotechnical Boring Location Plan, Figure 2, for the location of borings, and Appendix B, Field Investigation, for boring logs). • Laboratory testing of samples (See Appendix C). • Geotechnical engineering review of data and engineering recommendations. • Preparation of this report sununarizing our findings and presenting our conclusions and recommendations for the proposed constmction. Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa Resort. Carlsbad. CA Log No. 11-1409 SITE DESCRIPTION The project site is located on the northwestem portion of the existing MarBrisa Resort on Grand Pacific Drive south of Canon Road in Carlsbad, CA. Existing development at the MarBrisa Resort includes a hotel building, resort conference facility building, restaurant building, sales building, villas, paved driveway and parking, and associated retaining walls and landscaping. Mass grading for the entire MarBrisa Resort including the project site under this investigation was performed in 2005 and 2006 under the observation and testing of Leighton and Associates, Inc. The sales building site located on the southeast comer is elevated with a ground elevation of approximately 215 feet. The site for the planned activity and fitness building including two swimming pools and future villas are located on the gently slopes down to the west with elevation ranging from 198 feet to 186 feet. Currently this area is tilled with partial plants widiin the southeast. Numerous shallow underground water lines exist on the entire lot for irrigation purposes. The As-Graded Report by Leighton and Associates, Inc. dated August 2, 2006 reveals the tennis court area is mantled by approximately 14 to 18 feet of documented fill. The other area of the site is mantled by varying thickness of documented fill ranging from 2 to 13 feet. Expansive clayey soil was buried at the time of mass grading within the future planned parking lots. FIELD EXPLORATION The subsurface conditions at the project site were explored with six test borings. Two of the borings were drilled within the pool area and four of the borings were drilled within the sales building location. The approximate boring locations are shown on the Boring Location Plan (Figure 2). All borings were advanced with a tmck mounted drill rig equipped with an 8" diameter hollow stem auger. The borings were drilled to a depth of between 20 and 50 feet below existing site grades. Samples were obtained with the Standard Penetration Test (SPT) and CAL Sampler for geotechnical testing. See Appendix B for further discussion of the field exploration including logs of test borings. Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa Resort. Carlsbad. CA Log No. 11-1409 LABORATORY TESTING The laboratory testing included moisture content of the disturbed and undisturbed samples. The maximum density was determined on selected samples of the near surface soils for compaction and shrinkage calculations. Direct shear and consoUdation testing were accomplished for foundation bearing determinations. Soluble sulfates were determined on selected on-site soil samples to determine its degradation on concrete stmcture. Resistivity and pH testing were performed on representative soil for corrosion potential of buried metals. Index testing including sieve analysis and expansion index were performed on selected soil samples. R-value testing was performed for pavement design analysis. The results and expanded explanation of laboratory testing are presented in Appendix C. GEOLOGY Regional Geology The site lies within the Peninsular Ranges province of Southern California. The Peninsular Ranges are a group of mountain ranges, in the Pacific Coast Ranges, which stretch 1500 km from southern California in die United States to the southern tip of Mexico's Baja California peninsula. They are part of the North American Coast Ranges that run along the Pacific coast from Alaska to Mexico. Elevations range from 500 ft to 11,500 ft. Rocks in the ranges are dominated by Mesozoic granitic rocks, derived from the same massive batholith which forms the core of the Sierra Nevada Mountains in Califomia. They are part of a geologic province known as the Salinian Block which broke off the North American Plate as the San Andreas Fault and Gulf of California came into being. According to Kennedy (1975), the Peninsular Ranges province includes two principal rock units. The underlying basement rocks include igneous and metamorphic rocks and the overlying rock units include sedimentary rocks of a variety types. The basement rocks are structurally complex, metamorphosed volcanics and volcaniclastic rocks and intaisive rocks related in part to emplacement of the Cretaceous age southern California batholith which forms the backbone of the Peninsular Ranges province. The overlying sedimentary rocks were deposited on a high relief surface. Most of the overlying sedimentary rocks are Upper Cretaceous age strata of Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa ResorL Carlsbad. CA Log No. 11-1409 marine, lagoonal, and nonmarine origin related to two major transgressive and regressive depositional episodes. The geologic stmcture of southem Califomia is dominated by right-lateral strike-slip faulting with the movement of two tectonic plates. The San Andreas fault system marks the principal boundary between the Pacific plate and the North American plate. Additional faults that affect the geologic stmcture of die project vicinity include the Elsinore-Julian Fault and the Rose Canyon Fault. Local Geology The project site is located within a developed area with documented fill. Based upon available geologic map (Tan and Kennedy, 1996, Oceanside, San Luis Rey and San Marcos 7.5' Quadrangles), the underlying natural soil at the site consists of die Pleistocene-aged Terrace deposits. The Terrace deposits are composed of reddish-brown, poorly bedded, poorly- to moderately-indurated sandstone, siltstone and conglomerate. This unit was encountered in all borings below the fill at approximate depth of between 8 and 18 feet below existing site grades. Site Geologic Conditions A brief discussion of the earth materials encountered in the borings is presented in the following sections. Refer to the borings logs in the Appendix B for a more detailed description of these materials. Fill Documented fill material was encountered in all borings ranging in thickness between 7 and 18 feet from the surface. The encountered fill generally consists of brown to orange-brown silty sand, which was generally moist and medium dense to very dense at the time of our exploration. The documented fill in its current condition would be suitable for stmctural support for the proposed development. However, for uniform soil bearing support and to eliminate cut/fill transition conditions within building pad it is recommended that existing soil should be excavated and recompacted to a depth of at least 2 feet below bottom of footings. Lab test results indicate a very low expansion potential for the existing on-site fill soils. Sales. Activity & Fitness Buildings Project No. 1916-A08 MarBrisa Resort. Carlsbad. CA — Log No. 11-1409 Terrace Deposits Underlying the fill is Terrace deposits, which extend at least to the maximum explored depth of 50 feet below existing site grade. This encountered deposits generally consists of orange-brown silty sand. At the time of exploration the deposits were moist and dense to very dense. Expansion potential for this Terrace deposits is very low. Groundwater Groundwater was not encountered within the maximum explored depth of 50 feet below existing grade. Geotechnical reports by Leighton and Associates, Inc. reported localized perched groundwater encountered during their investigation and the subsequent mass grading at elevation between the terrace deposits and the underlying Santiago Formation. During our investigation the underlying Santiago Formation was not encountered. The perched groundwater would have no impact on the proposed development. However, it is possible that transient oversaturated ground conditions at shallower depths could develop at a later time due to periods of heavy precipitation, landscape watering, leaking water lines, or other unforeseen causes. DISCUSSION OF GEOLOGIC AND SEISMIC HAZARDS Faulting and Seismicity Faults are one of the most widespread geologic hazards to development in Califomia. Faults of most concem are those designated as active (less than about 11,000 years since last movement and potentially active (11,000 to about 750,000 years). According to Hart and Bryant, (2007) the site is not widiin a designated earthquake fault zone. In the event of an earthquake, the closest active fault likely to generate the highest ground accelerations at the site is the Rose Canyon Fault, which mns parallel to and just offshore of the coast from north of Carlsbad to south of Lindbergh Field. The Rose Canyon Fault with a maximum eartiiquake magnitude (Mw) of 7.2 is located approximately 8.5 km southwest of the project site. A number of other significant faults also occur in the San Diego metropolitan area suggesting that the regional faulting pattern is very complex. Faults such as those offshore are known to be active and any could cause a damaging earthquake. The San Diego metropolitan area has experienced some major earthquakes in the past, and will likely experience future major earthquakes. 5 Sales, Activity & Fitness Buildings P^j^'^t Na 1916-A08 MarBrisa Resort. Carlsbad. CA Log No. 11-14UV Other active faults which could cause ground shaking at the site include die offshore Newport- Inglewood Fault, located approximately 11.6 km to the northwest and the offshore Coronado Bank Fault, located approximately 21.1 km to the soudiwest. Liquefaction Potential Liquefaction involves die substantial loss of shear strengtii in saturated soil, when subjected to impact by seismic or dynamic loading. This usually occurs within a uniform fine-grained soil, with loose relative density, and low confining pressures. Liquefaction potential has been found to be greatest when die groundwater level is within 50 feet from die surface and loose fine sands or silts occur within that depth. Liquefaction potential decreases with increasing grain size, and clay and gravel content, but increases as die ground acceleration and duration of shaking increase. The on-site documented fill is underlain by terrace deposits, in tum, underlain by Santiago Formation. Due to the medium dense to very dense nature of the documented fill and the underlying formation unit, liquefaction potential at the site is negligible. Landslide. Mudflow and Flooding Landslide, mudflow and flooding are not considered a significant hazard at the site due to the absence of ascending slopes, valleys and rivers in die vicinity area. A review of die available Landslide Hazard Maps (DMG Open-File Report 95-04) indicates no mapped landslide within the project site. Ground Rupture No known active or potentially active faults, with known surface traces, cross the site. Therefore, the potential for ground mpture due to faulting is considered to be negligible. Seismic Settiement Saturated and non-saturated granular soils are subject to densification under strong shaking. The lower the density of the soils, the higher the intensity and duration of shaking, results in greater degree of densification. The project site is underlain by very dense formational unit that is Sales, Activity & Fitness Buildings MarBrisa Resort. Carlsbad. CA Project No. 1916-A08 Log No. 11-1409 considered not subject to settiement. Based on the anticipated earthquake effect and the stratigraphy of the site, seismically induced settlement is considered negligible. Lateral Spreading Lateral spreading may occur where liquefaction occurs at depth and there is either a nearby free face or there is a general slope of the terrain. The overlying non-liquefiable soils tend to break into blocks, which then may tilt and move laterally over the liquefiable soils. Given the stated low risk potential for liquefaction, we consider the potential for lateral spreading to be negligible. Tsunamis and Seiches Given diat the site is located a sufficient distance inland from the coast and due to its elevated location, inundation by tsunamis is considered to be nonexistent. Due to the lack of surface water impoundment in the immediate site vicinity, the seiche potential is also considered to be very low to nonexistent. Earthquake Accelerations / CBC Seismic Parameters The computer program Earthquake Ground Motion Parameters Version 5.1.0 was used to calculate the CBC site specific design parameters as required by the 2010 Califomia Building Code (CBC). Based upon boring data and SPT values, die site can be classified as Site Class D. The spectral acceleration values for 0.2 second and 1 second periods obtained from the computer program and in accordance with Section 1613.5 of the 2007 Califomia Building Code are tabulated below. Ground Motion Parameter Value 2007 CBC Reference Ss 1.252g Section 1613.5.1 Sl 0.473g Section 1613.5.1 Site Class D Table 1613.5.2 Fa 1.0 Table 1613.5.3(1) Fv 1.527 Table 1613.5.3(2) SMS 1.252g Section 1613.5.3 SMI 0.722g Section 1613.5.3 SDS 0.835g Section 1613.5.4 SDI 0.48 Ig Section 1613.5.4 Sales, Activity & Fitness Buildings Pf°jef No 1916-A08 M«rRrisaRe..nrt. Carlsbad. CA Log No. 11-1409 SUMMARY AND CONCLUSIONS General Considerations Given the findings of the investigation, die proposed project appears to be feasible from a geologic and geotechnical standpoint, provided the recommendations presented in diis report are fully incorporated into the design and constmction of the project. Specific conclusions pertaining to geologic conditions are summarized below: Excavation Characteristics The site is mantled by documented fill, underlain by terrace deposit. Excavation on diese materials can be accomplished widi die use of conventional constmction equipment. Expansion Potential Generally, the engineered fill and terrace deposits possess a very low expansion potential. As a result, the on-site soils are considered suitable for use as compacted fill within the project site. Cut/Fill Transition Conditions Widi the varying diickness of documented fill of between 2 and 18 feet, it is anticipated that proposed buildings and other stmctures to have cut/fill transition conditions. In order to minimize the potential for differential settiement in areas of cut/fill transitions, it is recommended that all proposed buildings and settlement sensitive stmctures to be entirely supported by properly compacted fill. A minimum 2 feet of compacted fill is recommended below bottom of footings. This minimum 2 feet compacted fill requirement should extend across die entire building pad and at least 5 feet beyond building footprint. Corrosivity Corrosion series tests consisting of pH, soluble sulfates, and minimum resistivity were performed on selected sample of the on-site soils. Soluble sulfate levels for the on-site soil indicate a negligible sulfate exposure for concrete stmcture. As such, no special considerations are required for concrete placed in contact with the on-site soils. However, it is recommended that Type n cement to be used for all concrete. 8 Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa Resort. Carlsbad. CA Log No. 11-1409 The corrosion potential of the on-site soil is moderate to high and considered to impact underground ferrous metals. The actual corrosive potential is determined by many factors in addition to those presented herein. MTGL, Inc. does not practice corrosion engineering. Underground metal conduits in contact with the soil need to be protected. We recommend that a corrosion engineer be consulted. RECOMMEMDATIONS General The recommendations presented herein are considered minimum and may be superseded by more conservative requirements of the architect, stmctural engineer, building code, or goveming agencies. The foundation recommendations are based on the load-deformation characteristics and shear strength of the onsite soils. In addition to the recommendations in diis section, additional general earthwork and grading specifications are included in Appendix E. Site Grading Recommendations Site Preparation Current improvements widiin proposed development include tennis court, plants and underground utilities. Prior to die start of any grading, all of diese existing improvements should be removed and utilities be relocated. Temporary Excavation We anticipate temporary excavation for the basement level would not exceed 15 feet below existing grade. Temporary vertical excavations of up to 4 feet deep for the on-site fill and terrace deposits would be generally stable. Excavation beyond 4 feet deep should be benched or sloped back not steeper dian 1:1 (horizontal:vertical) up to a maximum height of 15. Beyond 15 feet high temporary slopes should have an inclination of between 1:5:1 and 2:1. The on-site terrace deposits material and fill soil should be classified as Type C soil. Sales. Activity & Fiuiess Buildings Project No. 1916-AOS MarBrisa Resort. Carlsbad. CA Log No. 11-1409 Site Grading Sales Building - Grading of the pad includes cutting approximately 12 feet of the existing soil and the constmction of new fill slopes. The materials anticipated to be used in new fill slope grading consist of the onsite soil derived from the cutting of die site. It is anticipated that the finish fill slope for the building pad to be approximately 10 to 25 feet high. For slope stability purposes, the finished fill slope should have an inclination not steeper dian 2:1. Constmction of the new fill slope should include die excavation of key at the toe with a width of at least 8 feet and minimum depth of 2 feet below lowest adjacent grade into firm soil. Benching into the existing slope should be performed simultaneously during the fill slope constmction at a vertical interval of 2 to 4 feet. Additional grading recommendations within proposed building pad is to excavate and recompact the existing soil to a depth of at least 2 feet below bottom of footings for uniform soil bearing support and eliminate cut/fill transition condition. Activity and Fitness Buildings - A cut/fill transition condition could be anticipated widiin building pads. For uniform soil bearing support and to eliminate cut/fill transition condition, it is recommended that grading for the building to include removal and recompaction of the existing soil to a depth of at least 2 feet below bottom of footing elevation. Future Swimming Pools and Villas - Likewise with the above proposed stmctures, entire foundations are recommended to be supported by properly compacted fill. Existing soil should be removed and recompacted to a depdi of at least 2 feet below bottom of footing elevation for uniform soil bearing and eliminate cut/fill transition condition. If highly expansive clay is encountered widiin building pads, it should be removed and replaced with available onsite soil with low expansion potential. The depth of removal and replacement of highly expansive clay should be at least 3 feet below bottom of footing for buildings and at least 5 feet below bottom of slab for swimming pool. The removal and replacement should extend at least 5 feet beyond stmcture footprint. The lateral limit of grading for all stmctures should extend at least 5 feet beyond building footprint. Prior to recompaction process, the bottom of excavation to receive fill should be scarified to a depth of 6 inches, moisture conditioned and recompacted. 10 Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa ResorL Carlsbad. CA Log No. 11-1409 General Compaction Standard All fills should be compacted to a minimum of 90 percent relative compaction. All fill materials should be placed in thin lifts not more than 8 inches and compacted. Material should be moisture- conditioned and processed as necessary to achieve a uniform moisture content at near optimum moisture to achieve adequate bonding between lifts and compaction. Fill surfaces and finished subgrades should not be allowed to dry and should be maintained in a moist condition or scarified prior to placing additional fill. Fill soils outside stmcture and under vehicular pavement should be compacted to at least 90 percent relative compaction. However, die top 12 inches of subgrade under all vehicular pavement should be compacted to at least 95 percent relative compaction. Backfill of utilities should be compacted to a minimum of 90 percent relative compaction. All compaction shall be based on Test Method ASTM D1557. Moisture content of all fill and backfill soil should be at least 2 percent above optimum moisture content. Import Fill Material If required, import fill should consist of non-expansive granular soils, and have a maximum particle size of 1 inch. Import material should have an expansion index (EI) of 20 or less. Where import soils will be in contact with concrete or buried metal pipes a standard corrosion series test should be performed. Foundation The reconmiendations and design criteria are "minimum", in keeping with the current standard-of- practice. They do not preclude more restrictive criteria by the goveming agency or stmctural considerations. The project stmctural engineer should evaluate the foundation configurations and reinforcement requirements for actual stmctural loadings. Proposed stmctures are anticipated to be supported by properly compacted fill. Conventional continuous or isolated footings are considered suitable for stmctural support founded on engineered fill. Allowable soil bearing capacity for continuous or isolated footing with a minimum width of 2 feet are the following: 11 Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa Resort. Carlsbad. CA Log No. 11-1409 Embedment Below Lowest Adiacent Grade Allowable Soil Bearing Values 2 feet 5,000 psf 3 feet 6,500 psf 4 feet 8,000 psf (maximum) The above allowable bearing values may be increased by one-third where wind or seismic loads are considered in combination widi dead and/or live loads. Minimum horizontal setback distance from die face of slopes for all building footings should be H/2, where H is die slope height, with a maximum of 15 feet along 2:1 slopes. This distance is measured from the outside edge of the footing, horizontally to the face of slope. Lateral Resistance Lateral forces may be resisted by friction on the base of foundations, and passive earth pressure on the sides of the portions of foundations or shear keys bearing against competent native formation or compacted engineered fill. The allowable base friction may be calculated using a coefficient of 0.33. The allowable passive pressure may be calculated as equivalent to that of a fluid weighing 350 pounds per cubic foot (pcf) for foundations bearing against compacted engineered fill. Settlement For design consideration, a maximum settlement of at least 1-inch with a differential settlement of 1/2-inch in a span of 40 feet should be incorporated. Interior Slab-On-Grade Interior slab-on-grade should be designed for die actual applied loading conditions expected. The stmctural engineer should size and reinforce slabs to support the expected loads utilizing accepted mediods of pavement design, such as those provided by the Portland Cement Association or the American Concrete Institute. A modulus of subgrade reaction of 200 pounds per cubic inch (pci) could be utilized in design. Based on geotechnical consideration, interior slab should be a minimum of 5 inches. Appropriate slab reinforcement should be designed by the project stmctural engineer based upon low expansion potential. 12 Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa ResorL Carlsbad. CA Log No. 11-1409 Floor slabs should be underlain by a capillary break material consisting of at least 4 inches thick clean sand. In moisture sensitive flooring areas, such as carpeted or linoleum covered areas, a 10- mil visqueen moisture barrier or equivalent should be installed midheight within the capillary break material. Altematively, a Stego Wrap moisture barrier or equivalent may be installed following manufacturers recommendations. The sand should be moistened just prior to die placing of concrete. Concrete is a rigid brittie material that can withstand very little strain before cracking. Concrete, particularly exterior hardscape is subject to dimensional changes due to variations in moisUire of the concrete, variations in temperature and applied loads. It is not possible to eliminate die potential for cracking in concrete; however, cracking can be controlled by use of joints and reinforcing. Joints provide a pre-selected location for concrete to crack along and release sU-ain and reinforcement provides for closely spaced numerous cracks in lieu of few larger visible cracks. Exterior Concrete Slab/Flatwork Exterior slabs should be supported by at least 12 inches of properiy compacted fill. Compacted fill should have at least 90 percent relative density based on Test Method ASTM D1557. Exterior concrete slab/flatworks should have a nominal thickness of 4 inches. Reinforcement may be provided for stability purposes. Controlled joints should be provided to eliminate potential for cracking. Retaining Wall Embedded stmctural walls should be designed for lateral earth pressures exerted on them. The magnitude of diese pressures depends on the amount of deformation diat die wall can yield under load. If the wall can yield enough to mobilize the full shear strength of the soil, it can be designed for "active" pressure. If the wall cannot yield under the applied load, die shear strength of die soil cannot be mobilized and die earth pressure will be higher. Such walls as basement and swimming pools should be designed for the "at rest" conditions. If a stmcture moves toward die soils, the resulting resistance developed by the soil is the "passive" resistance. For design purposes, die recommended equivalent fluid pressure for each case for walls founded above die static ground water table and backfilled with on-site soils (expansion index less dian 20) is provided below. Retaining wall backfill should be compacted to at least 90 percent relative 13 Sales, Activity & Fiuiess Buildings Project No. 1916-A08 MarBrisa Resort. Carlsbad. CA . Log No. 11-1409 compaction (based on ASTM Test Method D1557). Recommended pressures are tabulated below. Equivalent Fluid Weight (p cQ Condition Level 2:HH:V) Slope Active 33 60 At-Rest 55 80 Passive 350 (Maximum of 3 ksf) 150 (Sloping Down) Soil resistance developed against lateral stmctural movement can be obtained from die passive pressure value provided above. Further, for sliding resistance, a friction coefficient of 0.33 may be used at die concrete and soil interface. The passive pressure and the friction of resistance could be combined without reduction. In addition, the lateral passive resistance is taken into account only if it is ensured that the soil against embedded stmctures will remain intact with time. Drainage of backfill behind walls may be provided by a vertical layer of Miradrain 6200 with Mirafi 140 Geofabric, or equivalent, placed at the back of the wall; or by a minimum 12-inch width of 3/4 inch open-graded cmshed gravel enveloped in Mirafi 140 Geofabric. Subdrains should consist of 4-inch diameter Schedule 40, PVC pipe or equivalent, embedded in approximately 1 ftVlinear foot of 3/4-inch down open-graded gravel, enveloped in Mirafi 140 Geofabric Filter or equivalent, with the pipe being 3± inches above the trench bottom; a gradient of at least 1% being provided to the pipe and trench bottom; discharging into suitably protected outlets. Altematively low-retaining walls (less than 5 feet retained) may use weep holes. Preliminary Pavement The preliminary pavement sections presented below are based on the R-value of the upper on-site soil (R-value of 25), assumed Traffic Index, and minimum pavement section based on the City of Carlsbad Supplemental Standard GS-17. Final pavement designs should be evaluated based on R- value tests of the actual subgrade material after completion of grading. Where die pavement is subject to repeated tuming stress (i.e. Trash Enclosures Aprons) the pavement should be Portland cement concrete. 14 Sales, Activity & Fitness Buildings MarBrisa Resort. Carlsbad. CA Project No. 1916-AOS Log No. 11-1409 Pavement Loading Condition Traffic Index AC Tliicluiess Class II Base Tiiickness Auto Parking Areas 4.5 4.0 inches 4.0 inches Auto Driveways 5.0 4.0 inches 4.0 inches Light Duty Tmck Driveways 6.0 4.0 inches 9.0 inches Moderate Duty Tmck Driveways 7.0 4.0 inches 11.0 inches All fill under pavement should be compacted to at least 90 percent relative compaction widi exception of the upper 12 inches. Prior to the placement of base material, the upper 12 inches of pavement subgrade should be scarified; moisture conditioned and compacted to a minimum 95 percent relative compaction based on Test Method ASTM D1557. Aggregate base material should conform to Caltrans Standard Specifications Section 26 (Class 2) or the Standard Specification for Public Works Constmction (Cmshed Aggregate Base or Cmshed Miscellaneous Base) and should be compacted to a minimum 95 percent relative compaction based on Test Method ASTM D1557 prior to placement of the asphaltic concrete. Portiand cement concrete pavement sections may incorporate steel reinforcement and to be provided with crack control joints as designed by the project stmctural engineer. Recommended concrete mix should be at least 3,500 psi. It is recommended that Portland cement concrete swales to be designed and constmcted within asphalt pavement areas for drainage of surface water. Fill soils under curb and gutter should be compacted to a minimum 90 percent relative compaction based on Test Method ASTM D1557. Constmction Considerations Moisture Sensitive Soils/Weather Related Concems The sods encountered at the site may be sensitive to disturbances caused by constmction equipment and to changes in moisture content. During wet weather periods, increases in the moisture content of the soil can cause significant reduction in the soil strength and support capabilities. In addition, soils diat become wet may be slow to dry and thus significantly retard die progress of grading and 15 Sales, Activity & Fitness Buildings Project No. 1916-A08 MarBrisa ResorL Carlsbad. CA Log No. 11-1409 compaction activities. It will, therefore, be advantageous to perform earthwork and foundation constmction activities during dry weather. Much of the on-site soils may be susceptible to erosion during periods of inclement weather. As a result, the project Civil Engineer/Architect and Grading Contractor should take appropriate precautions to reduce the potential for erosion during and after constmction. Drainage and Groundwater Considerations No groundwater was encountered within die maximum explored depth of 50 feet below existing grade. It should be noted, however, that variations in the ground water table may result from fluctuation in the ground surface topography, subsurface stratification, precipitation, irrigation, and other factors that may not have been evident at the time of our exploration. Seepage sometimes occurs where relatively impermeable and/or cemented formational materials are overiain by fill soils. We should be consulted to evaluate areas of seepage during constmction. Positive site drainage should be designed to reduce infiltration of surface water around and undemeath the building. Finish grades should be sloped away from the building. Excavations It is mandated by federal regulation that excavations, like utility trenches, basement excavation or foundation excavations, be constmcted in accordance widi the new OSHA guidelines. It is our understanding that OSHA regulations are being strictiy enforced and if not closely followed, the owner and the contractor could be liable for substantial penalties. The contractor is solely responsible for designing and constmcting stable, temporary excavations and should shore, slope, or bench the sides of the excavations as required to maintain stabiUty of both the excavation sides and bottom. The contractor's "responsible person", should evaluate the soil exposed in the excavations as part of the contractor's safety procedures. In no case, should slope height, slope inclination, or excavation depth, including utility trench excavation depth, exceed those specified in local, state, and federal safety regulations. 16 Sales. Activity & Fitness Buildings Project No. 1916-AOS MarBrisa ResorL Carlsbad. CA Log No. 11-1409 Utility Trenches Except where extending perpendicular under proposed foundations, utility trenches should be constmcted outside a 1:1 projection from die base-of-foundations. Trenches for utility lines under stmctures should be properly backfdled and compacted. Utilities should be bedded and backfilled widi approved sand or granular material to a depdi of at least 1-foot over die pipe. Sand bedding material should be moisture conditioned and properiy compacted. Compaction by jetting is not allowed. The remainder of the backfill may be typical on- site soil or imported soil which should be placed in lifts not exceeding 8 inches in thickness, watered or aerated close to optimum moisture content, and mechanically compacted to at least 95 percent (under stmcture and pavement) and 90 percent (not under stmcture and pavement) of maximum dry density (based on ASTM D1557). Site Drainage Drainage should be designed to collect and direct surface waters away from stiuctures to approved drainage facilities. Downspouts, berms, area drains and other drainage controls should be included in constmction considerations to minimize discharging or ponding of water near the foundation line. For earth areas, a minimum gradient of 1 percent should be maintained and drainage should be directed toward approved swales or drainage facilities. Positive drainage with a minimum gradient of 2 percent away from all stmctures should be provided and maintained within at least 5 feet from stmcture to reduce any mnoff from infiltrating the soil beneath stmctural foundation. Plan Review The geotechnical and geological consultants should be retained to review grading and foundation plans and specifications to ascertain conformance with site conditions and recommendations presented herein. Geotechnical Observation/Testing The geotechnical and geological consultants should be retained to perform on-site constmction observations and testing to ascertain diat conditions correspond to die findings and conclusions presented herein and that constmction conform generally to the recommendations presented herein. 17 Sales. Activity & Fitness Buildings P^j^^^t No 1916-A08 MnrRrisa Resort. Carlsbad. CA _ Log No. 11-1409 The geotechnical and geological consultants should be called upon for testing and observations as indicated in this report and at least for the following: • During site grading and overexcavation. • During foundation excavations and placement. • During excavation and backfilling of all utility trenches • Upon completion of any foundation and retaining wall footing excavation prior to placing concrete • During processing and compaction of the subgrade for the access and parking areas and prior to construction of pavement sections. It is the responsibility of the contractor to coordinate all inspections and testing required by diis firm or by other regulatory agencies. LIMITATIONS The analyses, conclusions, and reconmiendations contained in diis report are based on site conditions as diey existed at the time of our investigation and further assume die explorations to be representative of the subsurface conditions throughout the site. If different subsurface conditions are observed during constmction, we should be promptly notified for review and reconsideration of our recommendations. This report was prepared for the exclusive use and benefit of the owner, architect, and engineer for evaluating the design of the facilities as it relates to geotechnical aspects. It should be made available to prospective contractors for information on factual data only, and not as a warranty of subsurface conditions included in this report. Our investigation was performed using the standard of care and level of skill ordinarily exercised under similar circumstances by reputable soil engineers and geologists currently practicing in this or similar localities. No other warranty, express or implied, is made as to the conclusions and professional advice included in this report. 18 SITE LOCATION MAP SALES, ACTIVITY & FITNESS BUILDINGS zn Project No. 1916-A08 Date: NOV. 2011 FIGURE 1 MTGL, INC. Legend: B-6 Approximate Location of Boring BORING LOCATION PLAN 4 SALES, ACTIVITY & FITNESS BUILDINGS { Date: NOV. 2011 | FIGURE 2" Project No. 1916-A08 MTGL, INC. APPENDIX A REFERENCES Blake, Thomas F., 2000, "EQFAULT, A Computer Program for the Deteraainistic Prediction of Peak Horizontal Acceleration From Digitized Califomia Faults CDMG, Califomia Division of Mines and Geology, 2000, DMG CD 2000-003, Digital Images of Official Maps of Alquist-Priolo Zones. Bryant, W.A. and Hart, E.W.,2007, Fault Rupture Hazard Zones in Califomia, Alquist-Priolo Earthquake Fault Zoning Act with Index to Earthquake Fault Zones Maps, Califomia Department of Conservation, Califomia Geological Survey, Special Publication 42. Jennings, C.W., 1994, Fault Activity Map of Califomia and Adjacent Areas, Califomia Division of Mines and Geology. Scale 1:750,000. Califomia Department of Conservation, Division of Mines and Geology, Geologic Map of die Northwestem Part of San Diego County, Califomia, DMG Open-File Report 96-02. Scale 1:24,000. Califomia Department of Conservation, Division of Mines and Geology, Recent Failures, Ancient LandsUdes, and Related Geology of the North-Central Coastal Area, San Diego County, Califomia by F. Harold Weber, Jr, 1982, DMG Open-File Report 82-12, Scale 1:24,000. U.S. Geological Survey, Topographic Map of the San Luis Rey Quadrangle, Califomia-San Diego County, 7.5-Minute Series (Topographic), 1997, Scale 1:24,000. Califomia Department of Conservation, Division of Mines and Geology, 1995. Landslide Hazards in die Northem Part of the San Diego Metropolitan Area, San Diego County, CA, DMG Open-File Report 95-04, Landslide Hazard Identification Map No. 35. Califomia Department of Conservation, Division of Mines and Geology, The Rose Canyon Fault Zone , Southem Califomia, 1993, DMG Open-File Report 93-02. Califomia Building Standards Commission, 2007 Califomia Building Code, Califomia Code of Regulations, Title 24, Part 2, Volume 2 of 2. Department of die Navy, Naval Facilities Engineering Command, 1982, Foundations and Earth Stmcmres, NAVFAC DM-7.2. Department of the Navy, Naval Facilities Engineering Command, 1982, Soil Mechanics NAVFAC DM-7.1. Leighton and Associates, Inc., 2005, Geotechnical Investigation, Proposed 53-Acre Resort Development - Phase 1, Carlsbad Ranch, Planning Area No. 5, Carlsbad, CA, Project No. 040575-003, April 11,2005. Leighton and Associates, Inc., 2006, As-Graded Geotechnical Report of Rough and Fine Grading, Hotel One, Resort and Conference Facilites, Sales Building, and Villas No. 53 dirough 56, Lots 10, 11 and A Portion of Lot 1, Grand Pacific Carlsbad, Carlsbad, CA, Project No. 040575-005, August 2, 2006. APPENDIX B FIELD EXPLORATION PROGRAM On October 6, 2010, six exploratory borings were drilled utilizing 6-inch diameter hollow stem auger drilled to a depth of between 20 and 50 feet below existing site grade. Samples were obtained with the Standard Penetration Test (SPT) sampler, CAL Sampler and a bulk sample, as appropriate. The approximate location of the borings are shown on die Boring Location Plan, Figure 2, attached. The field exploration was performed under the supervision of our Geologist/Engineer who maintained a continuous log of the subsurface soils encountered and obtained samples for laboratory testing. The sods encountered were classified in general accordance with the Unified Soil Classification System (see Key to Logs, Figure B-0). Subsurface conditions are summarized on the Boring Logs, Figures B-1 and B-5. The soils were classified based on field observations and laboratory tests. DEFINITION OF TERMS PRIMARY DIVISIONS SYMBOLS SECONDARY DIVISIONS 0>2 - « 2 _ Ul o Ot-ct 'so Ul ^ozt! OC ^ > (0 _l O ta a m z < cc a UJ z til Ul CO Ijui < > CO CO CO 2 _l «^ Sd cc z UJ t< S X GRAVELS MORE THAN HALF OF COARSE FRACTION IS LARGER THAN NO. 4 SIEVE SANDS MORE THAN HALF OF COARSE FRACTION IS SMALLER THAN NO. 4 SIEVE CLEAN GRAVELS (LESS THAN S% FINES) QRAVEL WITH FINES CLEAN SANDS (LESS THAN 5% FINES) SANDS WITH FINES SILTS AND CLAYS LIQUID LIMIT IS LESS THAN 60% SILTS AND CLAYS LIQUID LIMIT 18 QREATER THAN 50% Wsll gradsd gravals. gravel-sand mixturaa, llttia or no flnas. GP Poorly gradad gravala or graval-sand mixturas. ItttIa or no finaa. GM Silty gravals, gravel-sand-aHt mixturas, non-plsstlo flnas. __ QC Clayey gravals. graval-aand-clay mixturas. plaatic flnas. SW Wall gradad sands, gravelly sands, little or no fines. SP SM SC ML CL OL MH CH OH Poorly graded sands or gravelly eands, little or no finaa. Silty sands, sand-silt mixtures, non-plastic fines. Clayey sandq, sand-clay mixturae, plaatic finaa. Inorganic silts and very fine aanda, rock flour, silty or] clayey fine sanda or clayey slits wHh alight plasticity. ' inorganic clays of low td medium piaatlclty. gravelly I claya. sandy ciaya. lean clays. ' Organic silts and organic allty ciaya of low plasticity. Inorganic silts, micacaoua or diatomaceoua fine aandy or silty soils, eiaatlc siita. Inorganic clays of high piaatlclty. fat ciaya. Organic claya of medium to hloh piaatlclty. organic slits. HIGHLY ORGANIC SOILS Pt Peat and other highly organic aoils. GRAIN SIZES SILTS AND CLAYSf SAND FINE MEDIUM COARSE GRAVEL FINE COARSE COBBLES BOULDERS 200 40 10 4 U.S. STANDARD SERIES SIEVE 3/4' 3' 12' CLEAR SQUARE SIEVE OPENINQS GROUND WATER LEVEL OR GROUND WATER SEEPAGE. LOCATION OF SAMPLE TAKEN USING A STANDARD SPLIT TUBE SAMPLER, 2- iNCH O.O.. 1-3/8-INCH I.D. DRIVEN WITH A 140 POUND HAMMER FALLING 30-INCHES. LOCATION OF SAMPLE TAKEN USING A MODIFIED CALiFORNiA SAMPLER. 3- 1/8-INCH O.O.. WiTH 2-1/2-INCH LD. LINER RINGS. DRIVEN USING THE WEIGHT OF KELLY BAR (LARGE DIAMETER BORINGS) OR USING A 140 POUND HAMMER FALLING 30-INCHES (SMALL DIAMETER BORING).' LOCATION OF SAMPLE TAKEN USING A 3-INCH O.D. THIN-WALLED TUBE SAMPLER (SHELBY TUBE) HYDRAULICALLY PUSHED. LOCATION OF BULK SAMPLE TAKEN FROM AUGER CUTTINGS. KEY TO LOGS - UNIFIED SOIL CLASSIFICATION SYSTEM (ASTM D-2487) JOB NO.: -I916A08 OATE: NOV. 2011 FIGURE: g_Q DATE OBSERVED: OcL 6, 2011 METHOD OF DRILLING: 8" HoMow Stem Auger LOGGED BY: ECD GROUND ELEVATION^ ±188' LOCATION: See Figure 2 8 > a m i , Ol a u BORING NO. B-1 DESCRIPTION SOIL TEST SB-1 SB-2 36 52 SB-3 76 15 SS-1 54 20 SS-2 56 25 SS-3 49 30 SS-4 55 35 40 13.5 12.5 9.3 11.8 10.4 13.4 10.4 122.9 120.4 LL: Silty Sand (SM), orange-brown, moist, medium dense, trace day. Grades to dense. Corrosivity l-value Gradation Direct Shear Consolidation TgRRACE DEPOSITS: Silty Sand (SM), orange-brown. 124.1 moist, very dense, mix yellow-brown color, trace clay. Grades with mix grey color. Grades with dark brown color. Grades to dense Grades to very dense. Boring Terminated at 30 Feet. No Groundwater Encountered. Borehole Backfilled on 10/6/2011. Project No.: 1916A08 LOG OF BORING Figure B-1 IDATE OBSERVED: Oct 6, 2011 METHOD OF DRILLING: 8" HollOW Stem Auger ILOGGED BY: ECD GROUND ELEVATION: ±190^ LOCATION: See Figure 2 8 KJ 5 S " Q BORING NO. B-2 DESCRIPTION SOIL TEST SB-1 SB-2 lie SB-3 lis SS-1 20 SS-2 |25 130 135 140 38 48 65 24 37 12.1 13.5 13.2 10.2 8.2 124.8 126.2 FILL; Silty Sand (SM), orange-brown, moist, medium dense to dense, trace clay. Grades to mix orange-brown Silty Sand. TERRACE DEPOSITS: Silty Sand (SM), orange-brown, moist, dense, mix with red-brown color. 123.8 Max. Density Expansion Index Corrosivity Direct Shear Consolidation Grades to medium dense Grades to dense. Boring Terminated at 20 Feet. No Groundwater Encountered. Borehole Backfilled on 10/6/2011. project No.: 1916A08 LOG OF BORING Figure B-2 DATE OBSERVED: Oct 6, 2011 METHOD OF DRILLING: 8" HollOW Stem Augcr LOGGED BY: ECD GROUND ELEVATION: ±215' LOCATION: See Figure 2 "=8 " Q BORING NO. B-3 DESCRIPTION SOIL TEST SB-1 SB-2 39 105 10 SB-3 36 IS SB-4 80 20 SS-1 48 25 SS-2 45 30 SS-3 25 35 40 14.3 8.1 123 132.8 =ILL: Silty Sand (SM), orange-brown, moist, medium dense, trace clay. Mix with dark brown color, very dense. l-value 11.7 125.8 Grades to medium dense. TERRACE DEPOSITS: Silty Sand (SM), orange-brown, 9.4 10.1 9.7 9.3 131.9 moist, very dense, trace clay. Grades to dense. Grades to medium dense. Boring Terminated at 30 Feet. No Groundwater Encountered. Borehole Backfilled on 10/6/2011. Project No.: 1916A08 LOG OF BORING Figure B-3 DATE OBSERVED: Oct 6,2011 METHOD OF DRILLING: 8" HollOW Stem Auger LOGGED BY: ECD GROUND ELEVATION: ±215' LOCATION: See Figure 2 CO H Oj Q 9 S * 5 D BORING NO. B-4 DESCRIPTION SOIL TEST SS-1 15 10 SS-2 22 15 SS-3 50/5" 20 SS-4 72 25 30 35 40 SS-5 37 SS-6 47 SS-7 SS-8 47 45 10.3 11.2 7.4 8.5 8.7 10.2 8.5 9.5 FILL: Silty Sand (SM), brown, moist, medium dense, trace clay. Grades to mix yellow-brown and orange-brown color. Grades to very dense. TERRACE DEPOSITS: Silty Sand (SM), moist, orange- brown, very dense, trace clay. Max. Density Expansion Index Corrosivity Grades to dense. continuation Figure B-4A Project No.: 1916A08 LOG OF BORING Figure B-4 DATE OBSERVED: Oct 6, 2011 METHOD OF DRILLING: 8" Hollow Stem Auger LOGGED BY: ECD GROUND ELEVATION: ±215' LOCATION; See Figure 2 Cfl § IB is g § " Q BORING NO. B-4 DESCRIPTION SOIL TEST 40 SS-8 45 45 SS-9 57 50 SS-10 55 60 65 70 75 BO 50/3' 9.5 9.8 5.7 TERRACE DEPOSITS: Silty Sand (SM), orange-brown. moist, dense, trace clay. Grades to gravel inclusions, very dense. Boring Terminated at 50 Feet. No Groundwater Encountered. Borehole Backfilled on 10/6/2100. Project No.: 1916A08 LOG OF BORING Figure B-4A DATE OBSERVED: Oct 6, 2011 METHOD OF DRILLING: 8" HollOW Stem Auger LOGGED BY: ECD GROUND ELEVATION: ±215' LOCATION; See Figure 2 Si CJ BORING NO. B-5 DESCRIPTION SOIL TEST SB-1 SB-2 41 47 SB-3 39 IS SB-4 37 20 SB-5 50/4' 25 SS-1 34 30 SS-2 57 35 SS-3 60 40 SS-4 70 -ILL: Silty Sand (SM), orange-brown, moist, medium dense, trace clay. 8.2 13.2 123.5 123.4 Gradation 13.8 11.6 10.4 10.1 10.4 9.9 7.9 123.4 Grades to mix dari< brown color. 124.6 Gradation Direct Shear Consolidation TERRACE DEPOSITS: Silty Sand (SM), moist, orange- brown, very dense, trace clay. 122.9 Grades to dense. Grades to very dense. Boring Terminated at 40 Feet. No Grounwater Encountered. Borehole Backfilled on 10/6/2011. Project No.: 1916A08 LOG OF BORING Figure B-5 DATE OBSERVED: Oct 6,2011 METHOD OF DRILLING: 8" HollOW Stem Auger LOGGED BY: ECD GROUND ELEVATION: ±215' LOCATION; See Figure 2 8 M EZ ^1 7 w BORING NO. B-6 DESCRIPTION SOIL TEST SB-1 53 10 SB-2 43 15 SB-3 35 20 SB-4 90 25 SS-1 37 30 SS-2 55 35 40 11.2 128.3 =ILL: Silty Sand (SM), orange-brown, moist, medium dense to dense, trace clay. Mix with dark brown color. Max. Density Expansion Index Corrosivity Gradation 12.9 122.1 10.8 9.2 9.8 8.6 121.4 Direct Shear Consolidation TERRACE DEPOSITS: Silty Sand (SM), orange-brown, moist, very dense, trace clay. 125.4 Grades to dense. Grades to very dense. Boring Terminated at 30 Feet. No Groundwater Encountered. Borehole Backfilled on 10/6/2011. Project No.: 1916A08 LOG OF BORING Figure B-6 APPENDIX C LABORATORY TESTING PROCEDURES GENERAL The results of laboratory testing are discussed and presented in this appendix. MOISTURE/DENSITY Determinadons of in situ moisture content and dry density were performed on selected undisturbed samples. Soil moisture content determinations were performed according to die ASTM D 2216. The dry density of soil was determined on CAL samples in general accordance with ASTM D2937. Results of diese tests are presented on the boring logs, Figures B-1 dirough B-2, in Appendix B. CLASSIFICATION The Unified Soil Classification System was utilized for visual (ASTM D2488) and laboratory (ASTM D2487) classifications of soils encountered. GRADATION The sieve analysis of selected soil samples was performed in accordance widi ASTM D422 and results are presented in Figures C-l to C-5 MAXIMUM DENSITY A maximum density test was performed on a representative bag sample of the near surface soils in accordance widi ASTM D1557. The test results are shown below. 1 Location Maximum Dry Density (pcf) Optimum Moisture Content (%) B-2 @ 8'- 12' 130.5 8.3 B-4 @ 8' -12' 134.2 8.5 B-6 @ 5' -9' 131.3 9.7 DIRECT SHEAR Direct shear tests were performed in general accordance with ASTM D3080-98. Direct shear tests were performed on undisturbed soil samples. Test results are as follows. Location Cohesion (PSF) Angle of Intemal Friction (Deg.) B-1 @ 5' 435 38 B-2 @ 10' 1003 40 B-5 @ 15' 1004 35 B-6 @ 15' 66 44 EXPANSION INDEX Expansion Index testing was completed in accordance with ASTM D4829. Test results are presented in the following table. Boring Depth Expansion Index UBC No. (feet) (EI) Potential Expansion B-2 8'-12' 0 Very Low B-4 8' -12' 0 Very Low B-6 5'-9' 5 Very Low CORROSIYITY Corrosivity Testing in compliance with Caltrans Test Method 417, 422, & 643. Test results are presented below. Sample Location PH Soluble Sulfates (%) Min. Resistivity (ohm-cm) B-1 @ r-5' 6.8 0.032 1,460 B-2 @ 8'- 12' 6.7 0.021 1,694 B-4 @ 8'-12' 6.6 0.011 1,781 B-6 @ 5' -9' 6.7 0.010 2,080 CONSOLIDATION Consolidation test was performed on representative, relatively undisturbed sample of the underlying soil to determine compressibility characteristics in accordance with ASTM D2435. Test result is presented on Figure C-6 to C-9. R-VALUE R-value testing was performed on existing upper on-site soil widiin proposed pavement areas. Califomia Department of Transportation (Caltrans) Test Method 301 was used to determine exudation and expansion values. Location R- Value B-i@ r-5' 25 B-3 @ 1' -5' 48 Particle Size Distribution Report 100 GRAIN SIZE - mm. 0.001 % +3" 0.0 % Gravel Coarse 0.0 Fine 0.6 %Sand Coarse 0.9 Medium 35.7 Fine 46.4 % Fines Silt 16.4 Clay SIEVE PERCENT SPEC* PASS? SIZE FINER PERCENT (X=NO) .375 100.0 #4 99.4 #10 98.5 #20 94.9 #40 62.8 #60 37.2 #100 24.2 #200 16.4 Material Description PL= Atterbera Limits LL= Pl= DQO= 07318 D50= 0.3338 DlO= Coefficients Do5= 0.6501 •30= 0.1986 Cg= •60= 0.4038 Dl5= uscs= Classification AASHTO= Remarks (no speciHcation provided) Sample Number: B-1 Depth: 5' Date: 10/24/11 MTGL, Inc. Anaheim, CA Client: Project: SALES / HTNESS BUILDING - MARBRISA PHASE 2 Proiect No: 1916-A08 re C-l Tested By: _JHL Checked By: ED_ Particle Size Distribution Report 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel Coarse Fine %Sand Coarse Medium Fine % Fines Silt _C!aj^ 0.0 0.0 6.1 3.4 27.1 29.4 34.0 SIEVE PERCENT SPEC* PASS? SIZE FINER PERCENT (X=NO) .375 100.0 #4 93.9 #10 90.5 #20 86.6 #40 63.4 #60 46.8 #100 39.2 #200 34.0 Materiai Description PL= Atterberq Limits LL= Pl= 090= 1-7910 050= 0.2834 0-10= Coefficients 085= 0.7921 030= 060= 0.3874 D15= USCS= Classificatlon AASHTO= Remarks (no specincation provided) Sample Number: B-2 Depth: 10' Date: 10/24/11 MTGL, Inc. Anaheim, CA Client: Project: SALES / HTNESS BUILDING - MARBRISA PHASE 2 Project No: 1916-A08 ure C-2 Tested By: _JH_ Checked By: ED_ Particle Size Distribution Report O OOQ O §°8 -t rt ^ to ^ CVJ . .E . ^ ^ .£ .S .S * .E-S S n evi J - # * GRAIN SIZE - mm. %+3" % Gravel Coarse Fine % Sand Coarse Medium Fine % Fines Silt Clay 0.0 0.0 0.0 0.0 16.6 49.0 34.4 SIEVE PERCENT SPEC* PASS? SIZE FINER PERCENT (X=NO) #4 100.0 #10 100.0 #20 98.9 #40 83.4 #60 59.2 #100 42.8 #200 34.4 Material Description PL= Atterberq Limits LL= Pl= 090= 0.5158 050= 0.1958 Oio= Coefficients 085= 0.4427 030= 060= 0.2545 Br USGS= Classificatlon AASHTO= Remarks (no specincation provided) Sample Number: B-4 Depth: 10' Date: 10/24/11 MTGL, Inc. Anaheim, CA Client: Project: SALES / FITNESS BUILDING - MARBRISA PHASE 2 Project No: 1916-AOS Figure C-3 Tested By: JH_ Checked By: ED. z UJ o IT Ul CL Particle Size Distribution Report i I i 100 GRAIN SIZE - mm. % +3" % Gravel Coarse Fine % Sand Coarse Medium Fine % Fines Silt Clay 0.0 0.0 0.0 0.5 177 48.2 33.6 SIEVE PERCENT SPEC* PASS? SIZE FINER PERCENT (X:=NO) #4 100.0 #10 99.5 #20 98.4 #40 81.8 #60 59.3 #100 43.4 #200 33.6 Material Descriotion PL= Atterbera Limits LL= Pl= 090= 0.5460 Di^= 0.1925 DlO= Coefficients 085= 0.4645 D30= 060= 0.2546 Dl5= USCS= Classification AASHTO= Remarks (no specincation provided) Sample Number: B-5 Depth: 15' Date: 10/24/11 MTGL, Inc. Anaheim, CA Client: Project: SALES / RTNESS BUILDING - MARBRISA PHASE 2 Project No: 1916-AOS Figure C-4 Tested By: JH_ Checked By: ED. Particle Size Distribution Report GRAIN SIZE - mm. % +3" % Gravel Coarse Fine % Sand Coarse Medium Fine % Fines Silt Clay 0.0 0.0 0.0 0.4 22.1 52.3 25.2 SIEVE PERCENT SPEC* PASS? SIZE FINER PERCENT (X=NO) #4 100.0 #10 99.6 #20 98.0 #40 77.5 #60 52.5 #100 35.0 #200 25.2 PL= 090= 0.5952 050= 0.2359 DlO= USCS= Material Description Atterberq Limits LL= Coefficients 085= 0.5127 030= Oil 56 Cu= Classification AASHTO= Pl= D60= 0.2941 gl5= Remarks (no specincation provided) Sample Number: B-6 Depth: 15' Date: 10/24/11 MTGL, Inc. Anaheim, CA Client: Project: SALES / HTNESS BUILDING - MARBRISA PHASE 2 Proiect No: 1916-AOS Figure C-5 Tested By: JH. Checked By: ED. 100 CONSOLIDATION TEST REPORT 200 500 1000 2000 Applied Pressure - psf 5000 Natural Sat. Moist. Dry Dens, (pcf) LL PI Sp. Gr. Overburden (psf) (psf) Swell Press, (psf) CIpse. 4163 0.1 MATERIAL DESCRIPTION USCS AASHTO Project No. 1916-A08 Client: Project: SALES / FTTNESS BUILDING - MARBRISA PHASE 2 Source: Sample No.: B-1 Elev7Depth: 5' MTGL, Inc. Anaheim, GA Remarks: Figure C-6 100 CONSOUDATION TEST REPORT 200 SOO 1000 2000 Applied Pressure - psf 5000 Natural Sat. Moist. Dry Dens, (pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) Cr Swell Press, (psf) CIpse. 1249 0.2 MATERIAL DESCRIPTION USCS AASHTO Project No. 1916-A08 Client: Project: SALES / FTTNESS BUILDING - MARBRISA PHASE 2 Source: Sample No.: B-2 ElevyPepth: 10' MTGL, Inc. Anaheim, CA Remarks: Figure C-7 100 CONSOLIDATION TEST REPORT 200 500 1000 2000 Applied Pressure - psf 5000 Natural Sat. Moist. Dry Dens, (pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) Swell Press, (psf) Swell 2693 1108 0.1 MATERIAL DESCRIPTION USCS AASHTO Project No. 1916-A08 Client: Project: SALES / FTTNESS BUILDING - MARBRISA PHASE 2 Source: Sample No.: B-5 ElevTDepth; 15' MTGL, Inc. Anaheim, CA Remarks: Figure C-8 100 CONSOLIDATION TEST REPORT 200 500 1000 2000 Applied Pressure - psf 5000 Natural Sat. Moist. Dry Dens, (pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) Swell Press, (psf) CIpse. 2559 0.1 MATERIAL DESCRIPTION USCS AASHTO Project No. 1916-A08 Client: Project: SALES / FTTNESS BUILDING - MARBRISA PHASE 2 Source: Sample No.; B-6 Elev^Depth: 15' MTGL, Inc. Anaheim, CA Remarks: Figure C-9 APPENDIX D ENGINEERING and SEISMIC ANALYSIS General The details of the engineering analyses performed as part of this investigation are discussed in this section. Seismicity Seismic design values were computed based on site coordinates of N33.13199 and Wl 17.31241. The nearest active fault computed by die Thomas Blake EQFAULT program is the Rose Canyon Fault, located approximately 8.5 km southwest of the site. The deterministic analyses are attached. The ground motion values derived from the 2010 Califomia Building Code (CBC), Titie 24 were obtained from the Java Ground Motion Parameter Calculator, Version 5.1.0 and is attached. Based upon the results of the exploratory borings, the project site is assigned to Site Class D. CALIFORNIA FAULT MAP Test Run 1100 1000-- 900 -- 800 -- 700 -- 600 -- 500 400 -- 300 -- 200 -- 100 -100 M I I I I I ' ' ' ' I ' ' I I I ' ' I ' I ' ' ' I M ' ' ' I -400 -300 -200 -100 0 100 200 300 400 500 600 TEST.OUT *********************** * * * EQFAULT * * * * Version 3.00 * * * *********************** DETERMINISTIC ESTIMATION OF PEAK ACCELERATION FROM DIGITIZED FAULTS JOB NUMBER: 1916-A08 _ DATE: 10-21-2011 30B NAME: Sales, Activity & Fitness Buildings CALCULATION NAME: Test Run Analysis FAULT-DATA-FILE NAME: CDMGFLTE.DAT SITE COORDINATES: SITE LATITUDE: 33.1320 SITE LONGITUDE: 117.3124 SEARCH RADIUS: ICQ mi ATTENUATION RELATION: 17) Campbell & Bozorgnia (1994/1997) - Alluvium UNCERTAINTY (M=Median, S=Sigma): M Number of Sigmas: 0.0 DISTANCE MEASURE: cdist SCOND: 0 Basement Depth: 5.00 km Campbell SSR: 0 Campbell SHR: 0 COMPUTE PEAK HORIZONTAL ACCELERATION FAULT-DATA FILE USED: CDMGFLTE.DAT MINIMUM DEPTH VALUE (km): 3.0 Page 1 TEST.OUT EQFAULT SUMMARY DETERMINISTIC SITE PARAMETERS Page 1 ESTIMATED MAX. EARTHQUAKE EVENT ABBREVIATED DISTANCE MAXIMUM PEAK EST. SITE FAULT NAME mi (km) EARTHQUAKE SITE INTENSITY MAG.(Mw) ACCEL, g MOD.MERC. ROSE CANYON 5.3( 8.5) 7.2 0.435 X NEWPORT-INGLEWOOD (offshore) 7.2( 11.6) 7.1 0.373 IX CORONADO BANK 21.1( 33.9) 7.6 0.218 VIII ELSINORE-TEMECULA 24.3( 39.1) 6.8 0.101 VII ELSINORE-JULIAN 24.3( 39.1) 7.1 0.129 VIII ELSINORE-GLEN IVY 35.4( 57.0) 6.8 0.063 VI PALOS VERDES 37.8( 60.8) 7.1 0.075 VII EARTHQUAKE VALLEY 42.4( 68.3) 6.5 0.038 V SAN JACINTO-ANZA 47.0( 75.6) 7.2 0.062 VI SAN JACINTO-SAN JACINTO VALLEY 47.8( 77.0) 6.9 0.047 VI NEWPORT-INGLEWOOD (L.A.Basin) 48.3( 77.7) 7.1 0.055 VI CHINO-CENTRAL AVE. (Elsinore) 49.8( 80.2) 6.7 0.037 V SAN JACINTO-COYOTE CREEK 51.7( 83.2) 6.8 0.039 V WHITTIER 53.3( 85.8) 6.8 0.037 V ELSINORE-COYOTE MOUNTAIN 56.2( 90.5) 6.8 0.035 V COMPTON THRUST 58.0( 93.3) 6.8 0.032 V ELYSIAN PARK THRUST 60.9( 98.0) 6.7 0.028 V SAN JACINTO-SAN BERNARDINO 61.3( 98.6) 6.7 0.028 V SAN JACINTO - BORREGO 64.9( 104.5) 6.6 0.024 V SAN ANDREAS - San Bernardino 65.7( 105.7) 7.5 0.053 VI SAN ANDREAS - Southern 65.7( 105.7) 7.4 0.048 VI SAN JOSE 70.6( 113.7) 6.5 0.019 IV PINTO MOUNTAIN 72.5( 116.7) 7.0 0.030 V SAN ANDREAS - Coachella 73.3( 117.9) 7.2 0.035 V SIERRA MADRE 74.3( 119.6) 7.0 0.027 V CUCAMONGA 74.6( 120.1) 7.0 0.026 V NORTH FRONTAL FAULT ZONE (West) 77.2( 124.2) 7.0 0.025 V BURNT MTN. 78.0( 125.6) 6.4 0.016 IV CLEGHORN 79.0( 127.2) 6.5 0.017 IV EUREKA PEAK 80.8( 130.1) 6.4 0.015 IV SUPERSTITION MTN. (San Jacinto) 81.0( 130.4) 6.6 0.018 IV NORTH FRONTAL FAULT ZONE (East) 81.2( 130.6) 6.7 0.018 IV SAN ANDREAS - 1857 Rupture 82.4( 132.6) 7.8 0.051 VI SAN ANDREAS - Mojave 82.4( 132.6) 7.4 0.036 V RAYMOND 82.5( 132.8) 6.5 0.015 IV CLAMSHELL-SAWPIT 84.2( 135.5) 6.5 0.015 IV ELMORE RANCH 84.7( 136.3) 6.6 0.017 IV VERDUGO 85.2( 137.1) 6.7 0.017 IV SUPERSTITION HILLS (San Jacinto) 85.7( 138.0) 6.6 0.017 IV HOLLYWOOD 87.1( 140.1) 6.4 0.013 III Page 2 TEST.OUT DETERMINISTIC SITE PARAMETERS Page 2 ABBREVIATED FAULT NAME LAGUNA SALADA LANDERS HELENDALE - S. LOCKHARDT SANTA MONICA LENWOOD-LOCKHART-OLD WOMAN SPRGS BRAWLEY SEISMIC ZONE MALIBU COAST JOHNSON VALLEY (Northern) EMERSON so. - COPPER MTN. NORTHRIDGE (E. Oak Ridge) SIERRA MADRE (san Fernando) SAN GABRIEL ********************************* -END OF SEARCH- 52 FAULTS FOUND APPROXIMATE DISTANCE mi (km) 87.4( 88.1( 89.4( 91.8( 93.1( 94.1( 94.3( 96.1( 96.2( 98.5( 99.0( 140.7) 141.8) 143.8) 147.7) 149.8) 151.4) 151.8) 154.6) 154.8) 158.5) 159.3) ESTIMATED MAX. EARTHQUAKE EVENT MAXIMUM EARTHQUAKE MAG.(Mw) 99.2( 159.7) 7.0 7.0 7.3 7.1 6.6 7.3 6.4 6.7 6.7 6.9 6.9 6.7 PEAK SITE ACCEL, g 0.023 0.030 0.025 0.014 0.028 0.012 0.015 0.016 0.019 0.016 0.014 0.020 EST. SITE INTENSITY MOD.MERC. ************************************* WITHIN THE SPECIFIED SEARCH RADIUS. FAULT IS CLOSEST TO THE SITE. IV V V IV V III IV IV IV IV IV IV ********* THE ROSE CANYON IT IS ABOUT 5.3 MILES (8.5 km) AWAY. LARGEST MAXIMUM-EARTHQUAKE SITE ACCELERATION: 0.4353 g Page 3 Conterminous 48 States 2005 ASCE 7 Standard Latitude = 33.13199 Longitude = -117.31241 Spectral Response Accelerations Ss and SI Ss and SI = Mapped Spectral Acceleration Values Site Class B - Fa = 1.0 ,Fv = 1.0 Data are based on a 0.01 deg grid spacing Period Sa (sec) (g) 0.2 1.252 (Ss, Site Class B) 1.0 0.473 (SI, Site Class B) Conterminous 48 States 2005 ASCE 7 Standard Latitude = 33.13199 Longitude = -117.31241 Spectral Response Accelerations SMs and SMI SMs = Fa X Ss and SMI = Fv x SI Site Class D - Fa = 1.0 ,Fv = 1.527 Period Sa (sec) (g) 0.2 1.252 (SMs, Site Class D) 1.0 0.722 (SMI, Site Class D) Contenninous 48 States 2005 ASCE 7 Standard Latitude = 33.13199 Longitude = -117.31241 Design Spectral Response Accelerations SDs and SDI SDs = 2/3 X SMs and SDI = 2/3 x SMI Site Class D - Fa = 1.0 ,Fv = 1.527 Period Sa (sec) (g) 0.2 0.635 (SDs, Site Class D) 1.0 0.481 (SD1, Site Class D) APPENDIX E GENERAL EARTHWORK AND GRADING SPECIFICATIONS APPENDIX E GENERAL EARTHWORK AND GRADING SPECIFICATIONS 1. GENERAL These specifications present general procedures and requirements for grading and earthwork as shown on the approved grading plans, including preparation of areas to be filled, placement of fill, installation of subdrains, and excavations. The recommendalions contained in the attached geotechnical report are a part of the earthwork and grading specifications and shall supersede the provisions contained herein in the case of conflict. Evaluations perfonned by the Consultant during the course of grading may result in new recommendations, which could supersede these specifications, or the recommendations of the geotechnical report. 2. EARTHWORK OBSERVATION AND TESTING Prior to the start of grading, a qualified Geotechnical Consultant (Geotechnical Bngineer and Engineering Geologist) shall be employed for the purpose of observing earthwork procedures and testing the fiDs for confonnance with the recommendations of the geotechnical report and these specifications. It will be necessary that flie Consultant provide adequate testing and observation so that he may detennine that the work was accomplished as spedfied. It shall be the responsibility of flie Contractor to assist the Consultant and keep them apprised of work schedules and changes so that he may schedule his . personnel accordingly. It shall be the sole responsibilily of flie Contractor to provide adequate equipment and methods to accomplish the work in accordance with applicable grading codes or agency ordinances, these spedfications and the approved grading plans. Maximum dry density tests used to determine the degree of compaction will be performed in accordance wifli the American Society for Testing and Materials Test Method (ASTM) D1557-91 or later revision. 3. PREPARATION OF AREAS TO BE FILLED Clearing and Grubbing: All brush, vegetation and debris shall be removed or piled and otherwise disposed of. Processing: Tlie existing ground which is determined to be satisfactory for support of fill shall be scarified to a minimum depth of 6 inches. Existing ground, which is not satisfactory, shall be overexcavated as specified in the following section. Overexcavation: Soft, dry, spongy, highly fractured or otherv%'ise unsuitable ground, extending to such a depth that surface processing cannot adequately improve the condition, shall be overexcavated down to firm ground, approved by the Consultant. Moisture conditioning: Overexcavated and processed soils shall be watered, dried-back, blended, and mixed as required to have a relatively uniform moisture content near the optimum moisture content as determined by ASTM D1557. Recompaction: Overexcavated and processed soils, which have been mixed, and moisture conditioned uniformly shall be recompacted to a minimum relative compaction of 90 percent of ASTM D1557. Benching: Where soils are placed on ground with slopes steeper than 5:1 (horizontal to vertical), the ground shall be stepped or benched. Benches shall be excavated in firm material for a minimum width of 4 feet. 4. HLL MATERIAL General: Material to be placed as fill shall be free of organic matter and other deleterious substances, and shall be approved by the Consultant. Oversize: Oversized material defined as rock, or other irreducible niaterial wifli a maximum dimension greater than 12 inches, shall not be buried or placed in fill, unless the location, material, and disposal methods are specifically approved by the Consultant. Oversize disposal operations shall be such that nesting of oversized material does not occur, and such that the oversize material is completely surrounded by compacted or densified fill. Oversize material shall not be placed within 10 feet vertically of finish grade or within the range of future utilities or underground construction, unless specifically approved by the Consultant. Import: If importing of fill material is required for grading, the import material shall meet the general requirements. 5. nLL PLACEMENT AND COMPACTION Fill Lifts: Approved fill material shall be placed in areas prepared to receive fill in near-horizontal layers not exceeding 6 inches in compacted thickness. The Consultant may approve thicker lifts if testing indicates the grading procedures are such that adequate compaction is being achieved with lifts of greater thickness. Each layer shall be spread evenly and shall be thoroughly mixed during spreading to attain uniformity of material and moisture in each layer. Fill Moisture: Fill layers at a moisture content less flian optimum shall be watered and mixed, and wet fill layers shall be aerated by scarification or shall be blended with drier material. Moisture conditioning and mixing of fill layers shall continue until the fill material is at uniform moisture content at or near optimum. Compaction of Fill: After each layer has been evenly spread, moisture conditioned, and mixed, it shall be uniformly compacted to not less that 90 percent of maximum dry density in accordance wifli ASTM D1557. Compaction equipment shall be adequately sized and shall be either specifically designed for soil compaction or of proven reliability, to efficiently achieve the specified degree of compaction. FiU Slopes: Compacting on slopes shall be accomplished, in addition to normal compacting procedures, by backrolling of slopes with sheepsfoot rollers at frequent increments of 2 to 3 feet as tlie fill is placed, or by other methods producing satisfactory results. At the completion of grading, the relative compaction of the slope out to the slope face shall be at least 90 percent in accordance with ASTM D1557. Compacbon Testine: Field tests to check the fill moisture and degree of compaction will be performed by the consultant. The location and frequency of tests shall be al the consultant's discretion. In general, these tests will be take at an interval not exceeding 2 feet in vertical rise, and/or 1,000 cubic yards of fill placed. In addition, on slope faces, at least one lesl shall be taken for each 5,000 square feel of slope face and/or each 10 feel of vertical height of slope. 6. SUBDRAIN INSTALLATION Subdrain systems, if required, shall be installed in approved ground to conform to flie approximate alignment and details shown on the plans or herein. The subdrain location or materials shall not be changed or modified without the approval of the Consultant The Consultant, however, may recommend and, upon approval, direct changes in subdrain line, grade or materials. All subdrains should be surveyed for line and grade after installation and sufficient time shall be allowed for the surveys, prior lo commencement of fill over the subdrain. 7. EXCAVATION Excavations and cut slopes wiD be examined during grading. If directed by the Consultant, further excavation or overexcavation and refilling of cut areas, and/or remedial grading of cut slopes shall be performed. Where fill over cut slopes are lo be graded, unless otherwise approved, the cut portion of the slope shall be made and approved by the Consultant prior to placement of materials for construction of the fill portion of the slope.