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HomeMy WebLinkAboutRS981987 - SOILSCOLEMAN GEOTECHNICAL �. 3002 DOW AVENUE, SUITE 414 t� TUSTIN, CA 92780 PHONE (714) 573-5776 FAX (714) 573-0438 V GEOTECHNICAL ENGINEERING SERVICES se GEOTECHNICAL INVESTIGATION New Residence Lot 17, Tract 15105, Beachcrest , Pelican Crest, Orange County, CA Client: !Bar Development, LLC c/o David Pierce Hohmann, Architect 19100 Von Karman Avenue, Suite 220, Irvine, CA Job No: 1618 April 2, 1998 TABLE OF CONTENTS Page 1. INTRODUCTION 1 1.1 General 1 1.2 Purpose and Scope of Work 1 2. INVESTIGATION AND LABORATORY TESTING 1 2.1 Field Exploration 1 2.2 Laboratory Testing 2 3. SURFACE AND SUBSURFACE CONDITIONS 2 3.1 Site Description 2 3.2 Soil Conditions and Site Geology 2 3.3 Seismicity 3 4. GEOTECHNICAL ANALYSIS AND CONCLUSIONS 4 5. DESIGN AND CONSTRUCTION RECOMMENDATIONS 5 5.1 Foundation Design and Construction 5 5.1.1 Vertical and Lateral Bearing 5 5.1.2 Settlement 6 5.1.3 Soil Design Parameters (Section 1815, 1994 UBC) 6 5.1.4 Seismic Design 6 5.2 Retaining Walls 6 5.3 Concrete Slabs 7 5.4 Expansive Soils 7 5.5 Soil Chemistry Considerations 9 5.5.1 Soluble Sulfates 9 5.5.2 Hazardous Materials 9 5.6 Stability Considerations 10 5.6.1 Trenches and Other Excavations 10 5.6.2 Graded Slopes 10 5.7 Site Design 11 5.7.1 Shrinkage and Subsidence 11 5.7.2 Drainage Design 11 5.8 Grading Recommendations 11 6. ADDITIONAL GEOTECHNICAL SERVICES 13 7. PROJECT MAINTENANCE CONSIDERATIONS 13 8. CLOSURE 13 9. REFERENCES 15 APPENDIX Laboratory Testing Procedures T-1,2 Grading Specifications - General Provisions S-1,2 Key to Soil Symbols and Terms A Maintenance Guidelines for Homeowners B Boring Logs C-D Seismicity Data eqf-1,2 Direct Shear Summary E Geotechnical Plan F 1 1. INTRODUCTION 1.1 General This report presents the results of a geotechnical study performed on Lot 17, Tract 15105, Pelican Crest, Newport Coast, Orange County, CA. Proposed for construction is new single family residence. The construction may include re- taining or garden walls which may or may not be shown on the currently available plans. Such walls should be considered as part of the structures to be constructed, and foundation design, construction, and grading recommendations presented below in this report should apply to these walls as if they were part of the building. Preliminary plans also indicate that a partial or full basement will also be included as part of the development. 1.2 Purpose and Scope of Work The purposes of this investigation were to: (1) obtain site specific information geologic con- ditions within the lot; (2) perform an engineering and geologic evaluation of the collected data and its influence on the project; and (3) provide geotechnical conclusions and recommenda- tions for design and construction. The work performed during this study included the following: 1. Collect and review project data available to us and develop an exploration program. 2. Engage a contractor to excavate two borings on the property and obtain representative bulk and "undisturbed" samples of the subsurface materials during our full-time observa- tion of the excavations. 3. Perform a visual geologic reconnaissance of the site and surrounding slopes to discern if any obvious unstable or otherwise adverse conditions exist. 4. Select representative samples for laboratory testing and perform laboratory tests to es- tablish the classification and engineering properties of the subsurface materials. 5. Analyze the collected data and prepare this report of our geotechnical conclusions and recommendations. 2. INVESTIGATION AND LABORATORY TESTING 2,1 Field Exploration The field investigation consisted of excavating two exploratory borings to a depth of 21 feet below the existing grades. The borings were excavated using a 8 inch diameter hollow stem drilling rig. Selected specimens of the in -situ soils were obtained by using a 2.5 inch I.D. drive tube sampler equipped with liner rings and a 2 inch O.D. by 1-3/8 inch I.D. Standard Penetration Test sampler. In addition to these relatively undisturbed specimens, bulk sam- ples of the soils were obtained for additional laboratory analysis. These soil samples served as the basis for the laboratory testing and the engineering conclusions contained in this re- port. The logs of the borings and a plot plan showing the approximate boring locations are included with this report. 1618geo.doc COLEMAN GEOTECHNICAL Page 1 2.2 Laboratory Testing The laboratory testing consisted of performing classification, strength, soluble sulfate, and expansion tests, determining the in -situ dry density and moisture content, and determining the moisture -density relationship of major soil types. The plasticity index of a representative sample was determined with the following results: Location Liquid Plastic Plasticity Limit Limit Index B-2 @ 0'-2' 28.4 20.6 7.8 Descriptions of the test standards used in this investigation in addition to other tests not used in this investigation are included in the Appendix of this report. The results of all laboratory tests are presented in the text below, in the Appendix, or on the boring logs. 3. SURFACE AND SUBSURFACE CONDITIONS 3.1 Site Description This lot is one of several created by mass grading to construct the overall Pelican Crest de- velopment. Mass grading on this property has created an elevated but gently inclined lot which drains toward the northwest. Manufactured two horizontal to one vertical (2:1) fill slopes descend from the northwesterly and southwesterly and ascend from the northeasterly property margins. The northwesterly slope is about 20 feet high and was, in part, created by construction of an approximately 12 foot high geo-grid reinforced Loffelstein retaining wall. Access to the property is off Beachcrest. At the time of our investigation, the lot was vacant. except for some minor surface debris. The bordering slopes are landscaped and appear well maintained. The slope surficial soils did not appear saturated or overly irrigated. Except for some desiccation cracks due to expansive soils, no unusual ground cracks, de- pressions, scarps, sinkholes, seeps, landslides, or other unusual or adverse geologic fea- tures were observed on the property. No evidence of uncontrolled, concentrated runoff onto or from the site has been noted during our investigation. 3.2 Soil Conditions and Site Geology Our subsurface investigation and review of previous reports (see references) has revealed that the subject lot is underlain entirely by engineered fill consisting mostly of mixed clay, silt and hard shaly bedrock fragments. At depths ranging from about 30 to 90 feet as reported in the referenced Leighton & Associates, Inc. report, the fill is underlain by sedimentary bedrock of the Monterey Formation. The compacted fill was placed as part of the previous mass grading performed on the site by the Irvine Company (see reference). Except for the imme- diate near -surface soils, which appeared disturbed and soft, the deeper fill materials are moist, stiff, and well compacted. The fill slopes were also observed and appeared grossly and surficially stable with only minor signs of erosion. 1618geo.doc COLEMAN GEOTECHNICAL Page 2 . % •••••• ? • • i: : * - r 16, TN • ''T•rZ • • A MN 13%° 1 /2 1 MILE 1 000 0 1 000 2000 3000 4000 FEET Printed from TOPO! ©1997 Wildflower Productions (mvw.topo.com) -1 A small desilting device was observed within the westerly comer of the lot which is probably connected to a subdrain. This device should not be modified or used as part of the site area drain system without consulting the Irvine Company. This lot also contains what appears to be an old settlement monument which is or was used to measure settlement following the completion of rough grading. The Irvine Company and it's geotechnical consultant should be contacted to determine if this monument is still in use or can be abandoned. No ground water or evidence of shallow ground water in the form of seeps, springs, secon- dary mineral deposits, mineral efflorescence, or concentrated growth of phreatophyte plants was observed on the property or during our subsurface investigation. More detailed descriptions of the subsurface conditions are shown on the attached boring logs. 3.3 Seismicity The subject property is not located within any Earthquake Special Studies Zones or astride a known active fault, and, accordingly, need not be considered for potential surface fault rup- ture. As the site is located in southern California, however, it is subject to strong ground shaking by a nearby or distant strong earthquake. However, the performance of structural engineer designed wood -frame structures, built in compliance with current building codes and founded into properly prepared earth materials, has generally proven to be satisfactory under condi- tions of earthquake induced strong ground shaking away from "near -field" fault rupture areas. Earthquakes which might occur on faults within a 60 mile (100 km.) radius from the site are listed below in the Appendix of this report, with their seismic parameters. The usual calculated 100-year probable repeatable horizontal ground accelerations in south- ern California range from 0.18 to 0.22g. The estimated project site accelerations are within ; this range. Secondary seismic hazards that are also considered for this project are seismic settlement, differential compaction, landsliding, earthquake induced flooding, tsunamis, and seiches. Each is addressed below. Potential for liquefaction, seismic settlement, and differential compaction - is considered low based on the clayey and well compacted nature of the fill and bedrock underlying the site, the lack of groundwater, and the replacement of readily compressible soils with engineered fill. Potential for Gross Landsliding - is considered to be low, based on the spatial orienta- tion of the fill /bedrock contacts, mass grading performed on the site, engineered slope ratios and heights, and material types and strengths. Potential for earthquake induced flooding, tsunamis, and seiches - can be precluded, as no upstream dams or other nearby bodies of water are present and due to the elevation of this lot above sea level. 1618geo.doc COLEMAN GEOTECHNICAL Page 3 4. GEOTECHNICAL ANALYSIS AND CONCLUSIONS 1. It is the opinion of this office that the subject site is suitable for support of the proposed development without detrimental effects on the adjacent properties. The grading, building construction, backfilling, and other construction supported by the earth materials should be conducted in accordance with the provisions of the applicable edition of the Uniform Building Code (U.B.C.) as adopted by the controlling agency. 2. The site is underlain by previously compacted fill soils which, when properly prepared and maintained are considered suitable for support of the proposed facilities. 3. The soils at the site possess high expansion potential and negligible soluble sulfate con- centrations. Recommendations are presented in this report to reduce the effects of soil expansion and other chemical factors. 4. Surficial slope stability may be affected by slope creep over the life of the project based on the expansion potential of the onsite soils, probable changes in soil moisture, and landscape maintenance variations. As a result, some minor separation between slabs, adjoining masonry walls, and others structural elements may be expected over the lifetime of the project. Some movement and distress may occur to shallow founded garden walls or hardscape areas constructed near or along the top of slope due to soil creep. This natural phenomena generally cannot be prevented. Appropriate recommendations to re- duce the effects of soil creep are found in Section 5.1. 5. No active faults are known to transect or trend towards the site, therefore the project is not expected to be affected by ground rupture. It will be affected by substantial ground motion from earthquakes during the design life of the project. More detailed seismicity data is included in the appendix of this report. 6. Adverse ground water conditions were not encountered during our investigation and is not considered a significant site development condition. 7. Adverse surface water discharge from runoff onto or from the site is not anticipated, pro- viding proper engineering design, construction, and maintenance of graded surfaces and drainage devices is implemented. 8. Conventional footings seated into compacted fill can be used to support the structure pro- viding the design and construction recommendations presented in this report and the re- quirements of applicable codes are followed. Concrete floor and hardscape slabs may be founded entirely on firm competent compacted fill. 9. Modification or grading of any of the existing slopes and in particular the main descend- ing slope which contains the Loffelstein wall should not be permitted without approval of the local governing agency and without consultation by geotechnical consultant. 1618geo.doc COLEMAN GEOTECHNICAL Page 4 5. DESIGN AND CONSTRUCTION RECOMMENDATIONS 5.1 Foundation Design and Construction 5.1.1 Vertical and Lateral Bearing Vertical The earth materials on this site when properly prepared are considered suitable for the sup- port of the proposed structures using conventional shallow continuous and/or pad footings. Footings may be designed using an allowable bearing value of 2,000 pounds per square foot for footings placed to a minimum width of 12 inches and a minimum depth of 24 inches below the lowest adjacent finished grade. An increase of 1/3 of the aforementioned bearing value is permissible for short duration wind or seismic loading. The above bearing values have been based on footings placed into approved compacted fill. These bearing values are considered to be net values and as a result the weight of the foot- ings and/or backfill above the footings may be ignored in calculating the footing loads. Lateral For purposes of resisting lateral forces, an allowable lateral soil pressure of 320 pounds per square foot per foot of depth may be used for the design. A coefficient of friction of 0.38 may be used for concrete placed directly on compacted fill. These values may be combined with- out reduction for resisting lateral forces. An increase of 1/3 of the above values may be used for short term wind or seismic loads. The above values are based on footings placed directly against previously compacted fill. In the case where footing sides are formed, all backfill against footings should be compacted to at least 90 percent of maximum density. Footing Setbacks To reduce the impact of soil creep, all footings constructed near and at the top of slopes should be constructed with an 8 foot setback from the lower outside footing edge to the face of slope. It is not possible to precisely predict the depth and distance behind the top of slope where slope creep may occur. This office should be notified for additional recommendations to help reduce the possible effects of soil creep where hardscape and garden walls may be constructed near the top of slopes. Foundation Construction All foundation excavations should be observed by the project soils engineer prior to the placement of forms, reinforcement, or concrete. The excavations should be trimmed neat, level, and square. All loose, sloughed, or moisture softened soil should be removed prior to concrete placement. Excavated material from footing excavations should not be placed in slab -on -grade areas unless properly compacted and tested. 1618geo.doc COLEMAN GEOTECHNICAL Page 5 5.1.2 Settlement Based on the general settlement characteristics of the in -situ soil types and the anticipated loading, it has been estimated that footings will settle less than 1/2 inch. Differential settlement is expected to be about 1/2 of the total settlement. It is anticipated that the majority of the settlement will occur shortly following the completion of construction. Differential settlement is anticipated to be less than 34 inch in any 20 foot horizontal distance. The above settlement estimates are based on the assumption that the grading will be per- formed in accordance with the grading recommendations presented elsewhere in this report and that representatives of this firm will observe or test the bearing conditions in the footing excavations. 5.1.3 Soil Design Parameters (Section 1815, 1994 UBC) The following geotechnical design parameters are presented, as defined in UBC Section 1815.2, Symbols and Notations: Parameter Design Value Co 1.7 Cs 1.0 Cw 15 PI 7.8 qu 200 psf 1-C 0.0 5.1.4 Seismic Design Seismic design of the structures should be performed using criteria presented in the Uniform Building Code for Zone 4 seismic conditions. 5.2 Retaining Walls Retaining walls may be designed using the following parameters: Bearing - 2,000 psf Active Earth Pressure (Cantilevered Walls) Level Backfill - 35 psf/ft At -Rest Earth Pressure (Restrained At Top Walls) Level Backfill - 55 psf/ft Passive Earth Pressure - 320 psf/ft Sliding Coefficient - 0.38 e , ,' nr c.c �2 . fovt- 2.• 1 s / ore / 6 J✓+C cv/ i I at i, -x aloy¢ 15- 5i 1618geo.doc COLEMAN GEOTECHNICAL Page 6 Sliding friction and passive resistance may be combined without reduction in calculating the total lateral resistance. Passive pressures may be assumed to become constant at a value of 5 times the above values below a depth of 5 feet. All retaining wall backfill should consist of soil with an expansion index of 20 or less. The soils existing on the site were found to possess high expansion potential. These soils should not be used for backfill of retaining walls. Retaining and basement walls must be provided with adequate sudrainage to reduce hydro- ; static pressures. As a minimum, the subdrain shall consist of a 4" perforated PVC drain pipe surrounded in 1 to 2 cubic feet per lineal foot of 3 inch gravel. The pipe and gravel shall in turn be enveloped in filter fabric. The drain shall be placed at the bottom of the walls and outletted to the storm drain or sump pump collection area. It is also recommended that all subterranean walls be waterproofed. Additional moisture protection can be provided with Miradrain or similar material placed against the wall as part of the drainage system. 5.3 Concrete Slabs It is our opinion that concrete floor slabs in areas to receive carpet, tile, or other moisture sensitive coverings should be constructed over a 6 mil plastic vapor barrier membrane. The plastic membrane should be properly lapped, sealed, and protected with at least a two inch thick layer of sand. The sand layer should be moistened just prior to placing concrete. It is cautioned that slabs in areas to receive ceramic tile or other rigid, crack sensitive floor coverings must be designed and constructed to reduce hairline cracking. Extra reinforcing and careful control of concrete slump to reduce concrete shrinkage are recommended. 5.4 Expansive Soils The results of tests indicate that the soils on the site possess high expansion potential. The test results are as follows: Sample Expansion Location Index B-1 @ 0-2' 100 B-2 @ 0-1' 102 The tentative design and construction details presented below may be considered for reduc- ing the effects of highly expansive soils. These recommendations have been developed based on the previous experience of this firm on projects with similar conditions and have been found to reduce, but not positively prevent, post -construction movement, cracking, and other effects of expansive soils. The owner, design civil engineer, structural engineer, and contractors must be made aware of the expansive soil conditions which exist on the site. Ad- ditional slab thickness, footing size and reinforcing should be provided as required by the structural engineer. 1618geo.doc COLEMAN GEOTECHNICAL Page 7 Additional testing will be performed during grading and final recommendations will be pre- sented in our Geotechnical Report of Rough Grading. It should be noted that slab, footing, and other construction details may change based on testing during grading. If a post tensioned foundation / slab system is utilized, the recommendations below may or may not apply. Tentative recommendations are as follows: Subgrade Treatment 1. Just prior to placing concrete floor slabs, the moisture of the soil should be at least 5 per- cent above optimum. This moisture content should extend to a depth of 18 inches. 2. The subgrade for garage floor slabs should conform to the above requirement. Footing Treatment 1. Exterior footings should be constructed to a minimum depth of 18 inches. The exterior footings should be reinforced with two No. 4 bars placed in the top and two No. 4 bars placed in the bottom of the footing. 2. Interior footings should be constructed to a minimum depth of 18 inches. The following are recommended design features of interior footings: a. The major interior footings should be tied into exterior footings for structural continuity. b. The continuous footings should be reinforced with one No. 4 bar placed in the top and one No. 4 bar placed in the bottom of the footing. 3. Reinforcing of individual isolated pad footings is not required for expansive soil purposes. 4. Footings should be carried across garage door openings as a grade beam. These should be reinforced as for exterior footings. Floor Slabs 1. Concrete floor slabs should be at least 4 inches thick actual. 2. The floor slabs should be reinforced with No. 3 bars at 18 inches on center each way. 3. Garage floor slabs should be free floating and cast independent of footing stems. A posi- tive separation should be provided between footing stems and concrete floor slabs. Ga- rage floor slabs should be reinforced with No. 3 bars at 24 inches on center each way. 4. Reinforcement for slabs -on -grade should be located in the center 1/3 of the thickness of the slab. Swimming Pool The proposed swimming will likely be excavated into expansive soils. The pool shell should be designed and/or reviewed by a structural engineer so that the added effects of expansive soil pressure are accounted for in the design. 1618geo.doc COLEMAN GEOTECHNICAL Page 8 5.5 Soil Chemistry Considerations 5.5.1 Soluble Sulfates The results of tests show that the onsite soils possess negligible concentrations of soluble sulfates. The test results are as follows: Sample % Soluble Location Sulfates B-1 0-1' 0.094% A soluble sulfate content less than 0.10 percent is not considered detrimental to standard concrete mixes. As a result, no special design or construction is considered necessary for soluble sulfates on this project. All concrete in contact with soils should meet or exceed the requirements of Chapter 19 and Table 19-A-3 of the 1994 Uniform Building Code. For your convenience, we have included the table below: TABLE NO 19-A-3 - REQUIREMENTS FOR CONCRETE EXPOSED TO SULFATE CONTAINING SOLUTIONS Moderate (2) Severe Very Severe 0.10 - 0.20 0.20 - 2.00 Over 2.00 150 -1500 1500 - 10,000 Over 10,000 II, IP, IS V (3) V Plus Pozzolan 0.50 0.45 0.45 4,000 4,500 4,500 (1) A lower Water - Cement Ratio or higher strength may be required for low permeability or for protection against corrosion of embedded items or freezing and thawing (2) Seawater (3) Pozzolan that has been determined by test or service record to improve sulfate resistance when used in concrete combined with Type V cement. 5.5.2 Hazardous Materials This investigation does not include any evaluation or assessment of hazardous or toxic mate- rials which may or may not exist on the site. 1618geo.doc COLEMAN GEOTECHNICAL Page 9 5.6 Stability Considerations 5.6.1 Trenches and Other Excavations Excavations Even though no caving was experienced during the subsurface exploration, it can be ex- pected that instability of utility trenches or other excavations will be experienced and, as a consequence, shoring or sloping excavation walls will be required to protect workers. The contractor should refer to the State of California, Division of Industrial Safety for minimum safety standards. No surcharge loads should be permitted above unshored or unretained excavations. This includes, but is not limited to vehicles carrying material or stockpiles of lumber, concrete block, or soil. Drainage above excavations must be directed away from the banks and care must be taken to prevent saturation of the soils. Due to the stiff and clayey characteristics of the existing fill materials, basement excavations up to 10 feet deep should be laid back at a maximum slope inclinations of 3/4:1 for temporary stability considerations. Although not ex- pected, this slope inclination should be reduced to 1.5:1 or flatter if loose sands or other un- stable bedrock conditions are uncovered during grading. Backfilis It should be noted that the County of Orange requires that the compaction of all utility trench backfilis be tested and commented on by the project soil engineer prior to final completion of the project and issuance of a certificate of occupancy. Materials to be used for backfilling utility trenches and retaining walls may consist of sand having a sand equivalent (SE) of 40 or more or excavated soil, at the contractor's option. Materials used for backfill should be placed in thin lifts and each lift should be mechanically compacted to at least 90 percent relative compaction and tested by the soil engineer. Self -compacting materials (i.e. pea gravel) may be placed behind the basement walls in lieu of compacted fill. This firm will give an opinion of the adequacy of the backfill of utility trenches only if the back - fill operations are observed during the backfilling work and only if tests are obtained as the work progresses. If testing is performed after all backfilling is complete, without the benefit of observation of the work, only the test results at the test locations can be reported. 5.6.2 Graded Slopes All permanent slopes on this project should be constructed at slope ratios of 2 horizontal to 1 vertical or flatter. No slopes over five feet in height are planned as part of the current design concept. No new slopes over five feet in height are planned on this project. 1618geo.doc COLEMAN GEOTECHNICAL Page 10 5.7 Site Design 5.7.1 Shrinkage and Subsidence Calculations have been performed based on the in -situ density of the soils and the estimated compacted density of the soils after grading to estimate the shrinkage which might be ex- pected between cutting and filling. It is estimated that shrinkage on this project could range from 8 to 15 percent. Subsidence as a result of the grading operations could range up to 0.1 feet in these types of soils. Please note that these estimates should be used with extreme caution. Contingencies must be developed for balancing the earthwork quantities based on the actual shrinkage and subsidence which occurs during grading. This firm assumes no responsibility for the use of these earthwork factors or the balancing of earthwork quantities on this project. 5.7.2 Drainage Design This project should be designed and constructed with drainage devices at gradients ade- quate to insure proper drainage after the completion of construction. The potential for post construction movement of finished surfaces due to the presence of soils with high expansion potential must be considered in the drainage design at this site. Such considerations may include the use of greater surface gradients than normal as well as the use of planters with solid bottoms and drainage pipes immediately adjacent to structures or pavement. It is important that drainage patterns established during finish grading of the site be main- tained throughout the life of the structures. Property owners should be aware that altering drainage patterns during landscaping or at any other time can affect the performance of the structures and other site improvements. In addition, variations in irrigation and seasonal rainfall can also affect the performance of on site facilities. It is strongly recommended that irrigation and other sources of water be controlled on this site to prevent overwatering. The clayey soil encountered on this site is expansive and may lose strength if allowed to become saturated. 5.8 Grading Recommendations The following special grading provisions are recommended for the grading of this project in addition to the Grading Specifications, General Provisions included in the Appendix of this report. 1. The construction may include retaining or garden walls which may or may not be shown on the currently available plans. Such walls should be considered as part of the struc- tures to be constructed, and foundation design, construction, and grading recommenda- tions presented in this report should apply to these walls as if they were part of the house structure. 1618geo.doc COLEMAN GEOTECHNICAL Page 11 2. The existing soil in all building and hardscape areas outside the basement footprint area shall be overexcavated to a depth of 18 inches below rough pad grade or existing grade, whichever is deeper, and the resulting surface scarified to a depth of 6 inches prior to placing new compacted fill. The soil placed in the upper 18 inches of the structure areas shall be placed at a moisture content of at least 5 percent above optimum moisture con- tent if existing on -site or similar soils are used. If significant drying occurs prior to slab placement, moisture conditioning of the slab area by flooding or other means may be needed prior to slab placement. 3. As the bottom of the basement should expose formerly placed compacted fill, no addi- tional overexcavation and recompaction is considered necessary. This will be reviewed once the basement grade is exposed. 4. All scarification and removals specified herein shall extend to a distance of at least 3 feet beyond all footing edges unless property line or other constraints exist. Special recom- mendations will be presented during grading for grading in those areas where constraints are present. 5. Soil utilized for filling shall consist of approved on -site or imported soil. On -site soils which are free of trash, debris, and organic materials can be considered as suitable. 6. Any imported soil shall be approved by the soil engineer for both expansive and strength qualities prior to importation to the project site. Final acceptance of any imported soil will be based on observation of the soil actually delivered to the site. 7. Pavement subgrade soil shall be compacted to at least 90 percent relative compaction. 8. All other fill shall be compacted to at least 90 percent relative compaction. 9. The maximum density of all soils shall be determined in accordance with A.S.T.M. Test Method D-1557. The maximum density of aggregate base shall be determined in accor- dance with California Test Method 216. 10. Areas to receive pavement shall be compacted to at least 90 percent relative compaction to a depth of at least 12 inches below final subgrade elevation. Final subgrade compac- tion shall be performed just prior to placing aggregate base or asphaltic concrete after compaction and testing of all utility trench backfills. The moisture content of the subgrade soils should be at least 3 percent above optimumto a depth of 12 inches just prior to placing aggregate base. 11. All finalized foundation and grading plans shall be forwarded to the soil engineer for re- view and comment prior to the start of construction. 1618geo.doc COLEMAN GEOTECHNICAL Page 12 6. ADDITIONAL GEOTECHNICAL SERVICES The recommended bearing values presented in this report are based on the assumption that the footings will be supported directly on firm, compacted fill. All footing excavations should be observed prior to placing steel or concrete to insure that the footings are founded on suit- able material. All grading and fill compaction should be observed and/or tested by this firm, including rough grading, installation of special drainage devices, retaining wall backfills, utility trench backfills, precise grading, and pavement subgrade and aggregate base, if applicable. It is the responsibility of the owner or his representative to review the recommendations pre- sented herein and to authorize the other design consultants and contractors to perform such work as necessary to comply with the recommendations as well as to inform this firm when necessary observations or testing are needed. 7. PROJECT MAINTENANCE CONSIDERATIONS Attached to this report is a "Maintenance Guidelines for Homeowners" sheet which discusses items which should be a part of the homeowners maintenance of the lot or tract. The condi- tions discussed on this attachment are of paramount importance to the long-term stability of slopes, but should be read and considered at any site, especially those where the expansion index is reported as being greater than 40. 8 CLOSURE This report has been prepared for the exclusive use of David Pierce Hohmann Architects to assist the project design consultants and contractors in the design and construction of the proposed development. It is recommended that this firm be engaged to review the design drawings and specifications prior to construction to verify that our recommendations have been properly interpreted and included in the design. If we do not perform this review, we can accept no responsibility for misinterpretation of our recommendations. This firm strives to perform it's services in a manner consistent with generally accepted cur- rent professional principles and practice in geotechnical engineering. We make no other warranty, either expressed or implied. It has been assumed, and it is expected, that the geotechnical conditions which exist be- tween the test excavations are similar to those encountered in the test excavations. How- ever, no warranty of such is implied in this report. The conclusions and opinions contained in this report are based on the results of the de- scribed geotechnical evaluations and represent our best professional judgment. The findings, conclusions, and opinions contained in this report are to be considered tentative only, and subject to confirmation by the undersigned during the construction process. Without this confirmation, this report is to be considered incomplete and this firm or the undersigned pro- fessionals assume no responsibility for its use. In addition, this report should be reviewed and updated after a period of one year or if the site ownership or project concept changes from that described herein. 1618geo.doc COLEMAN GEOTECHNICAL Page 13 This report is issued with the understanding that it is the responsibility of the owner or his representative to insure that interested parties have this information. This report is subject to review by the controlling goveming authorities for the subject project. It must be noted that this report may not meet all the requirements of the controlling agency since codes and agency interpretation of same are continually changing, and a review docu- ment may be issued which requires additional analysis and follow up information. This addi- tional work will be performed at the billing rates which have been established. Respectfully submitted, COLEMAN GEOTECHNICAL James R. Coleman G.E. 229 Lee A. Shoemaker C.E.G. 1961 1618geo.doc COLEMAN .GEOTECHNICAL Page 14 9. REFERENCES 1 Geotechnical Report of Rough Grading, Including Loffelstein Wall and Retaining Wall Construction, Planning Area 1 C-2, Tract 15105, Phase II Builder Area, Newport Coast, County of Orange, Califomia (Their Project No. 1892112-10) (Orange County Grading Permit No. GA940115). 1618geo.doc COLEMAN GEOTECHNICAL Page 15 APPENDIX 1618geo.doc COLEMAN GEOTECHNICAL Page 16 LABORATORY TESTING PROCEDURES Below are brief descriptions of the laboratory tests which are performed by our firm on various projects. All of these may, or may not, have been performed as part of our analysis on the subject project. The selection of which samples to be tested and which tests to perform is a part of the professional services performed. ykSHEAR STRENGTH The shear strength of the soil is determined by performing direct shear tests in accor- dance with A.S.T.M. Test Method D-3080. Direct shear tests are performed on either "undisturbed" or remolded samples which represent anticipated conditions at the finished site. The samples are either tested at in -situ moisture or are saturated to simulate the most severe field conditions expected. The relationship between the norn gal sts css and shear stress are shown on the Direct Shear Summary. EXPANSION Tests for Expansion Index are performed on compacted samples in accordance with Uniform Building Code (UBC) Test Method 18-2. Test results are included within the report body. SETTLEMENT The settlement characteristics of soil samples are determined by performing consoli- dation tests on "undisturbed" or remolded specimens in accordance with A.S.T.M. Test Method D-2435. The samples are tested in the original sample liner ring and the incremental loads for consolidation are applied for periods of 12 or 24 hours by means of a single counterbalanced lever system. Sample consolidation is measured in increments of 0.0001 inches. The pres- sure -consolidation curves are shown in the appendix. n MOISTURE -DENSITY The moisture -density relationship of the various soil types is determined in accordance with A.S.T.M. Test Method D-1557. The results are shown on the subsurface Togs. '••'�►• CLASSIFICATION '� `G' , The following test methods are used to aid in the classification of soils in accordance with the Unified Soil Classification system: 1. Particle size analysis - A.S.T.M Test Method D-422 2. Liquid Limit / Plastic Limit - A.S.T.M. Test Method D-423 The results of these tests are included on the Grading Analysis sheets or are tabulated within the report body. Iabtest.doc COLEMAN GEOTECHNICAL 12/97 Page T-1 RESISTANCE "R"-VALUE • The resistance "R"-Value of soils is determined in accordance with California Test Method 301. The results are used for pavement design purposes. SAND EQUIVALENT The sand equivalent (S.E.) of granular soils and fine aggregates in determined in ac- cordance with A.S.T.M. Test Method D-2419. The results are used to determine the applica- bility of the material for use as fill or backfill and to establish whether flooding or jetting is a suitable compaction method. SOLUBLE SULFATE CONTENT - The concentration of soluble sulfates in the soil is determined by A.S.T.M. Test Method D-516, Method A, and is expressed- as a percentage by weight of the dry soil. -The re - =v suits are included within the body of the report and are utilized in determining suitable concrete mixes. CORROSION POTENTIAL The potential for the soil to corrode buried metal components is consists of determin- ing the following: 1. Soil pH (Acidity -Alkalinity) 2. Soluble Chloride content in accordance with California Test Method 417. 3. Minimum Resistivity in accordance with Califomia Test Method 643. These results are included within the body of the report and are intended to be utilized by a Corrosion Engineer in determining protection methods for various buried metal components of the project. Iabtest.doc COLEMAN GEOTECHNICAL 12/97 Page T-2 GRADING SPECIFICATIONS GENERAL PROVISIONS These specifications are presented to be used wholly, or in part, either as pre- sented or as a guide for the preparation of separate grading specifications. 1. RESPONSIBILITY 1.1 The geotechnical consultants are his clients representative on the project. For the purposes of these specifications, observations and/or testing by the soil engineer includes the observation and/or testing performed by any person or persons assigned by, and responsible to, the licensed geotechnical engineer signing the report. 1.2 All clearing, site preparation, or earthwork performed on this project shall be conducted by the contractor(s) with periodic or full-time observation and -test- ing by the geotechnical engineer. 1.3 It is the contractors responsibility to conform to the Grading Specifications for the project and the applicable grading ordinances for the jurisdiction in Which the project is located... Services performed, and test results obtained, by; the geotechnical consultants in no way relieve the contractors) from their respon sibilities. 2. CLEARING 2.1 The site shall be cleared of all vegetable growth and other deleterious materi- als including, but not limited to, trees, stumps, logs, trash, heavy weed growth, and organic deposits. 2.2 Unless otherwise approved, all remnants of any previous facilities on the site shall be removed from the site. Included with the removal of foundations and slabs shall be the removal of basements, cellars, cisterns, septic tanks, pav- ing, curbs, pipes, storage tanks, improperly abandoned water or petroleum wells, and other deleterious materials. No cavity created by demolition shall be backfilled until it has been observed by the geotechnical engineer. 2.3 Unless otherwise specified, all cleared materials shall be removed from the boundaries of the project to an approved disposal site. The determination of the acceptability of the material for disposal or the disposal site is not the re- sponsibility of Coleman Geotechnical. 3. SITE PREPARATION 3.1 Loose soils within areas of fill shall be processed by either excavating and stockpiling the loose soil or by scarifying, adjusting the soil moisture content to the amount specified elsewhere in this report, and compacting to the recom- mended relative compaction as determined by A.S.T.M. Test Method D-1557. gradspec.doc COLEMAN GEOTECHNICAL 12/97 Page S-1 3.2 The soils within areas of fill placement shall be processed to a depth adequate to insure the removal of major tree roots and pipelines and the compaction of cavaties left from tree removal. 3.3 Excavation voids created following the removal of subsurface structures shall be cleared of any loose soil, the resulting surface moisture conditioned, and filled with compacted soil. The backfill of such excavations shall be com- pacted to the relative compaction recommended elsewhere in this report. 3.4 Cesspools shall be pumped of liquids and solids and backfilled with clean sand, pea gravel, "birds eye", or sand -cement slurry. Sand backfill may be flooded and jetted into place for compaction. Any unsuitable backfill shall be removed when found to not be in compliance with the recommendations con- tained in this report. Preparation of cesspools for backfilling shall be observed by the soil engineer. Permits may be required by governing agencies for the - project, and: any specifications which the agency has should be complied with, unless the above is more restrictive. 3.5 Abandonment of oil, gas, or water wells shall be performed in accordance with applicable state :or : local., laws. The backfiiling of any voids left from . such-_:. abandonment shall be perfor i red as specified in Section 3.3, above. 3.6 Unless otherwise specified, the tops of any abandoned subsurface structure shall be removed to a depth of 5 feet below any planned improvements, such as footings, slabs, utility lines, future swimming pools, etc. 4. FILL PLACEMENT 4.1 Unless otherwise approved and unless a specific rock disposal plan is shown on the plans in this report, no cobbles over 12 inches in diameter shall be ac- cepted in any fill. 4.2 All on site and imported soils to be used for an engineered fill shall be subject to the approval of the geotechnical engineer prior to placement. Preliminary approval of a source of imported soil shall not relieve the contractor of deliv- ering proper material to the site. Final acceptance of imported soil will be based upon the material actually delivered to the site. 4.3 Fill shall be placed in near horizontal lifts with a maximum placed thickness such that the required compaction can be achieved for the entire lift thickness with the available equipment and methods. 4.4 Site and project specific recommendations for overexcavation, processing, special materials, fill placement, and compaction shall be as recommended in the "Grading Recommendations" section in the main body of this report and any addendum reports which have been prepared by the geotechnical con- sultants for the project. gradspec.doc COLEMAN GEOTECHNICAL 12/97 Page S-2 COLEMAN GEOTECHNICAL 3002 DOW AVENUE, SUITE. 414 TUSTIN, CA 92680 PHONE (714) 573-5776 FAX (714) 573-0438 GEOTECHNICAL ENGINEERING SERVICES KEY TO SOIL SYMBOLS AND TERMS Terms used for describing soils according to their Texture, Grain Size, and Moisture Content. Terms are generally in accordance with the Unified Soil Classification System SNOISIAIO iorvw FINE GRAINED SOILS (More than half of material Is finer than #200 sieve) COARSE GRAINED SOILS (More than half of material is larger than #200 sieve) HIGHLY ORGANIC SOILS SILTS AND CLAYS (Liquid Limit Greater Than 50) SILTS AND CLAYS (Liquid Limit Less Than 50) More tharihaifDof coarse fraction is finer than #4 sieve More than half of coarse fraction is larger than #4 sieve SANDS WITH FINES CLEAN SANDS GRAVELS WITH FINES CLEAN GRAVELS UNIFIED SYMBOLS PT OH CH MH OL CL ML SC SM SP SW GC GM GP GW v '1 v ."/".//,' 1 7.14/7 /,',:; .41 ' : ::::-: .:..7-.:: X?:;) 6 6$ 1, , l' 4' (::, .).''C>7 1 TYPICAL NAMES PEAT and other Highly Organic Soils Organic Clays and Silts of High Plasticity Inorganic Clays of High Plasticity, Fat Clays Inorganic Silts, Micaceous or Diatomaceous fine sandy or silty soils, Elastic Silts Organic Silts and Organic silty Clays of low plasticity inorganic Clays of low plasticity, sandy Clays, silty Clays, Lean Clays Inorganic Silts and very fine Sands, Rock Flour, clayey Silts wl slight plasticity Clayey Sands, Sand - Clay mixtures Silty Sands, Sand - Silt Mixtures Poorly graded Sands, gravelly Sands, little or no fines Well graded Sands, gravelly Sands, little or no fines Clayey Gravels, Gravel -Sand -Clay mixtures Silty Gravels, Gravel -Sand -Silt mixtures Poorly graded Gravels, Gravel - Sand mixtures, little or no fines Well graded Gravels, Gravel - Sand mixtures, little or no fines HARDNESS & DENSITY CONSISTENCY SHEAR SPT "N" VALUE RELATIVE DENSITY SPT "N" VALUE STRENGTH Very Loose Less Than 4 Loose 4-10 Medium Compact 11-30 Compact 31-50 Very Compact Greater Than 50 Very Soft Less Than 0.25 tsf Less Than 2 Soft 0.25 - 0.50 tsf 2 -4 Firm 0.50 -1.00 tsf 5 - g Stiff 1.00 - 2,00 tsf 9 .15 Very Stiff 2.00 - 4.00 tsf 16 -30 Hard Greater Than 4.00 tsf Greater Than 30 MOISTURE From low to high, the soil moisture is indicated by: Dry (Very Rare) Damp Slightly Moist Moist (Near Optimum) Very Moist Wet (Saturated) TERMS CHARACTERIZING SOIL STRUCTURE Slickensided • having inclined planes of weakness that are slick and glossy In appearance. Fissured i containing shrinkage cracks, frequently filled with fine soil, nearly vertical. Laminated a composed of thin layers of varying color and texture. Interbedded i composed of alternating layers of different soil types Calcareous u contains appreciable amounts of calcium carbonate. Well Graded i having a wide range in grain sizes and substantial amounts of intermediate particle sizes. Poorly Graded i predominantly one grain size or having a range in grain sizes with some intermediate sizes missing. Porous i having visibly apparent void spaces through which water, air, or light may pass. SAMPLER • TYPES s B Ring SPT Bulk ?16 L A MAINTENANCE GUIDELINES FOR HOMEOWNERS lfomesites, in general, and hillside lots, in particular, need maintenance to continue to function and retain their value. Many )omeowners are unaware of this and allow deterioration of their property. It is important that homeowners be familiar with some guidelines for maintenance of their properties and that they be aware of the importance of maintenance. overning agencies require hillside property developers to utilize specific methods of engineering and construction to rrotect those investing in improved Tots or constructed homes. For example, the developer may be required to grade the property in such a manner that surface water will be drained away from the lot and to plant slopes so that erosion will be Minimized. He may also be required to install permanent drains. 1,lowever, once the lot is purchased, it is the buyer's responsibility to maintain these safety features by pursuing a prudent program of lot care and maintenance. Failure to make regular inspection and to maintain drainage devices and sloping I areas may cause severe financial loss. In addition to his own property damage, the owner may be subject to civil liability for damage occurring to neighboring properties as a result of his negligence. If the tract slope ownership and maintenance is the responsibility of the homeowners association, individual owners can aid `)eir association by observing conditions in the immediate area of their home, and reporting any possible problems to their ssociation. The following maintenance guidelines are provided for the protection of the homeowner's investment: Care should be taken that slopes, terraces, berms (ridges at crown of slopes) and proper lot drainage are not dis- turbed or impaired. Surface drainage should be conducted from the rear yard to the street through the side yard, or alternative approved devices. In general, roof and yard runoff should be directed to the street or storm drain by nonerosive devices such as sidewalks, drainage pipes, ground gutters, and driveways. Drainage systems installed by the developer should not be altered without expert consultation. All drains should be kept cleaned and unclogged, including gutters and downspouts. Terrace drains or gunite ditches should be kept free of debris to allow proper drainage. During heavy rain periods, performance of the drainage system should be observed. Problems, such as gullying and/or ponding, if observed, should be corrected as soon as possible. Any leakage from pools, waterlines, etc., or surface flow by-passing drains should be repaired or corrected as soon as practical. 5. Animal burrows should be eliminated since they may cause diversion of surface runoff or deep saturation of surficial soils, promote accelerated erosion, and even trigger shallow soil slumps or failures due to loosened and saturated surficial soils. 6. Slopes and near slope areas should not be altered without expert consultation. Whenever a homeowner plans a significant topographic modification of the lot or slope. a qualified geotechnical consultant should be contacted. In the case of rear yard areas near the top of slope, a "significant" topographic modification could be the addition of as little as one foot of soil against a garden wall to create a planter area. This type of modification is often performed as a part of pool and deck construction, and often causes wall distress, movement, and possibly failure of the nearby slope. I. If the homeowner plans modification of cut, fill, or natural slopes within his property, a geotechnical consultant should be contacted. Any oversteepening will likely result in a need for retaining devices, per building code requirements. Undercutting of a toe -of -slope would reduce the safety factor of the slope and should not be undertaken without expert consultation. 8. If any unusual cracking, settling or earth slippage occurs on the property. the owner should consult a qualified soil engineer or engineering geologist immediately. The most common causes of slope erosion and shallow slope failures are as follows: Neglect of the care and maintenance of the slopes and drainage devices. ** Inadequate and/or improper planting. Barren areas should be replanted as soon as possible. ** Excessive or insufficient irrigation or diversion of runoff over the top of slope. 0. Whether required by the governing agency, or not, a geotechnical expert should be consulted prior to and during any near slope construction, ESPECIALLY swimming pools. patio slabs. or landscaping which results in the placement of ANY fill. �1 Hillside lot owners should not let conditions on their property create a problem for their neighbors. Cooperation with �._ neighbors in maintaining proper drainage and landscaping could reduce problems, promote slope stability, and also increase the aesthetic attractiveness of the community. 1�ACrC 6 COLEMAN GEOTECHNICAL SUBSURFACE LOG CLIENT: David Pierce Hohmann / IBar Development JOB NO: 1618 DATE: 3/19/98 BORING NO. B-1 EQUIPMENT. [ ] HAND AUGER [ ] BUCKET AUGER [ x ] HOLLOW STEM [ ] BACKHOE DIAMETER: 8" ADDRESS: Lot 17, Tract 15105, Pelican Crest, Newport Beach, CA LOGGED BY: LAS DDMDRCM RE YNXNLMI S (pcf) AE S (pcf) EO P (%) 0 S T(%) D E P T H (ft) B U L KP S A M L "N"V A LIA ULS E S C 0 L s SOIL / BEDROCK DESCRIPTION 104 2 5 F I L L F I L L FILL: Mixed Silty CLAY and Bedrock Frag- aments, light brown, dry and soft in upper 12", moist and firm below, firm to stiff below 2 ` feet -stiff, approximately 60% soil 40% bedrock chips and fragments -Sandy CLAY with hard angular bedrock fragments, yellowish Tight brown, mottled, moist, firm -Clayey SAND and Silty CLAY, dark olive gray, tan, and light brown, firm, moist, contains at 10-30% angular bedrock chips and fragments, mottled appearance 91 24.5 R 85 22.1 10 R 93 17.0 15 R 86 31.1 20 R 119 14.7 25 R Bottom of Boring c@ 21.0 Feet No Groundwater or Seepage Noted • 30 35 This log is a representation of conditions at the time and place of excavation. With the passage of time and at other locations, conditions may vary. • SHEET _1_ OF _1_ APPENDIX PAGE c COLEMAN GEOTECHNICAL SUBSURFACE LOG CLIENT: David Pierce Hohmann / IBar Development . JOB NO: 1618 DATE: 3/19/98 BORING NO. B-2 EQUIPMENT [ i HAND AUGER [ ] BUCKET AUGER DIAMETER: 8" ADDRESS: Lot 17, Tract 15105, Pelican Crest, Newport Beach, CA LOGGED BY: LAS DD RE Y N S (pot) MD AE X N S (pcf) RC E O L M P (%) M O I S T(%) D E P T H (ft) B U L KP S A M L "N"V A L ULS E S C O L I A $ SOIL / BEDROCK DESCRIPTION 2 5 19 17 21 28 21 F L L F I L L FILL: Mixed Silty CLAY and Bedrock Frag- ments, light brown, dry and soft in upper 12", moist and firm below, firm to stiff below 12" -Silty CLAY, SILT, and Fine Grained BEDROCK Fragments, gray and light brown, moist, stiff, mottled appearance, most bedrock fragments are angular 27.2 S 28.1 10 S 15 S 20 S 25 S r Bottom of Boring © 21.0 Feet No Groundwater or Seepage Noted 30 35 This log is a representation of conditions at the time and place of excavation. With the passage of time and at other locations, conditions may vary. SHEET _1_ OF _1_ APPENDIX PAGE ************************************* * * * EQFAULT * * * Ver. 2.20 * * * * ************************************* (Estimation of RHGA Horizontal Acceleration From Digitized California Faults) DATE: Thursday, April 2, 1998 JOB NUMBER: 1618 SEARCH PERFORMED FOR: David Pierce Hohmann / IBAR Development, LLC JOB NAME: Residence, Lot 17, Tract 15105, Pelican Crest, Newport Coast, Orange County, CA SITE COORDINATES: LATITUDE: 33.5953 N, LONGITUDE: 117.8388 W SEARCH RADIUS: 60 mi ATTENUATION RELATION: 1) Campbell & Bozorgnia (1994) Horiz. - Alluvium UNCERTAINTY (M=Mean, S=Mean+1-Sigma): M, SCOND: 0 COMPUTE RHGA HORIZ. ACCEL. (FACTOR: 0.650 DISTANCE: 20.0 mi) FAULT -DATA FILE USED: CALIFLT.DAT SOURCE OF DEPTH VALUES (A=Attenuation File, F=Fault Data File): A ANACAPA CASA LOMA-CLARK (S.Jacin.) CATALINA ESCARPMENT CHINO CLAMSHELL-SAWPIT CORONADO BANK-AGUA BLANCA CUCAMONGA ELSINORE ELYSIAN PARK SEISMIC ZONE GLN.HELEN-LYTLE CR-CLREMNT HOT S-BUCK RDG.(S.Jacinto) MALIBU COAST NEWPORT-INGLEWOOD (NORTH) N ORT' 'NG.LEWOOD OFFSHORI • 59 ( 95) 49 ( 79). 32 ( 51) 22 ( 36) 41 ( 66) 18 ( 29) 41 ( 65) 22 ( 36) 35 ( 56) 45 ( 73) 55 ( 88) 51 ( 82) 24 ( 39) 7.00 7.00 7.00 7.00 6.60 7.50 6.90 7.50 7.10 7.00 7.00 6.90 6.70 0.037 0.049 0.085 0.137 0.045 0.150 0.058 0.192 0.084 0.055 0.043 0.042 0.092 V VI VII VIII VI VIII VI VIII VII VI VI VI VII 5.70 7.00 6.10 5.40 4.90 6.70 6.10 6.60 5.80 6.70 6.10 5.60 4.20 0.013 0.049 0.039 0.040 0.011 0.084 0.031 0.095 0.030 0.042 0.019 0.015 0.010 III VI V V III VII V VII V VI IV IV 'III 1NORTH FRONTAL FAULT ZONE '1 53 ( 86)1 7.701 0.0821 VII 11 6.001 0.0181 IV 1 1 1 1 1 11 1 1 etc'- ABBREVIATED FAULT NAME NORTHRIDGE HILLS OAK RIDGE (Eastern Blind) PALOS VERDES HILLS RAYMOND ROSE CANYON SAN ANDREAS (Mojave) SAN ANDREAS (S. Bern.Mtn.) SAN CLEMENTE - SAN ISIDRO SAN DIEGO TRGH.-BAHIA SOL. SAN GABRIEL SAN GORGONIO - BANNING SAN JOSE SANTA MONICA - HOLLYWOOD SANTA MONICA MTNS. THRUST SIERRA MADRE-SAN FERNANDO VERDUGO WHITTIER - NORTH ELSINORE WILSHIRE ARCH APPROX. DISTANCE mi (km) 57 ( 91) 58 ( 94) 16 ( 25) 39 ( 63) 40 ( 64) 52 ( 84) 51 ( 82) 55 ( 89) 42 ( 68) 43 ( 69) 46 ( 74) 32 ( 51) 43 ( 69) 45 ( 72) 37 ( 59) 40 ( 65) 21 ( 34) 39 ( 63) MAX. CREDIBLE EVENT MAX. CRED. MAG. 6.50 7.00 7.20 7.50 7.00 8.00 8.00 8.00 7.50 7.40 7.50 6.70 7.00 7.20 7.30 6.70 7.10 5.70 RHGA SITE ACC. g 0,026 0.056 0.144 0.095 0.064 0.108 0.111 0.100 0.092 0.082 0.077 0.066 0.058 0.096 0.089 0.050 0.149 0.035 SITE INTENS MM V VI VIII VII VI VII VII VII VII VII VII VI VI VII VII VI VIII V MAX. PROBABLE EVENT MAX. PROB. MAG. 5.50 5.50 6.20 4.90 5.90 7.40 6.70 6.50 6.20 5.60 6.60 5.00 5.80 6.30 6.30 5.20 6.00 5.00 RHGA SITE ACC. g 0.012 0.017 0.068 0.012 0.024 0.065 0.036 0.027 0.030 0.017 0.038 0.014 0.022 0.047 0.041 0.015 0.060 0.020 SITE INTENS MM III IV VI III VI V Iv V IV IV VI V IV VI IV ***************************************************************************** -END OF SEARCH- 33 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE NEWPORT-INGLEWOOD-OFFSHORE FAULT IS CLOSEST TO THE SITE. IT IS ABOUT 2.5 MILES AWAY. LARGEST MAXIMUM -CREDIBLE SITE ACCELERATION: 0.310 g LARGEST MAXIMUM -PROBABLE SITE ACCELERATION: 0.222 g SHEARING LOAD, P.S.F. 2000 1600 1200 800 400 0 jZ 5' MOIL 57''itavq!w 0 400 SAMPLE INFORMATION CAW-4 Boring No, ES —I Depth: Oar 800 1200 NORMAL LOAD, P.S.F. TEST INFORMATION ;: Undisturbed • Remolded Moisture Content ■ Saturated C Natural Remolded Density • 90% of Max. 0 Natural 1600 2000 COLEMAN GEOTECHNICAL 3002 DOW AVENUE, SUITE 414, TUSTIN, CA 92782 PHONE (714) 573-5776 FAX (714) 573-0438 DIRECT SHEAR SUMMARY JOB NO. DATE DRAWN BY 4PPENDIX PAGE /6/8 3198 Page E aeC • • // r' (�.•`r lfyd / �. -++ 4�i •12AZ •14t4 / ., 17 / /^ : /'r 7 L 4f ///� r `� � a3 // rG✓ P..!St�?� 'LW-1y .: �;/ f i , . • a►Isoa r ♦uo =`,424;, • �, :.. ' I. , % •�oi2 Colo• 1 '• xDta • tyq� ` ; , •1121 ♦217 , % . \•, c 'I i •12h `�\, 6f 123 'i, •,429e '` •L'L ,►.455 iy� �• '' 654 �M6 , • / ; • 1 : • ' VII • -� - . /' • 12 1ti' •`113 -- *—* I , thes f ' • uss \ �1 r> ,` / `•, 'Q�Y2.6 /// ; % . 1 • • , \Ar\ 44) iv / 2a•�� �,� • 'tea • € 57 i .l a• / �( islet,,. j. <4, J ' c,' , • e / ( b;1 ' aye, 4 ' ,,c, 7 / . 1. �o ($ Lw~ ! 2096� I Q I2ap % / �P 1i4^ _ ��yy - `y • 1� 4 P 1lid t I • • 1490 \tom.) ♦ f zn .�+ i •, ea , , /:.. �9.. / •1272 ' .. •12217 , 11r.� •t49 �: 3► r r/. '• 2019 • LW-61 '• I /�/ I 0 93 4 Ate' 1420 ." •2 �f' rt r ,,,, / • Af >, •)113 yr Y• �r '0 R'1 S.C1 ' w $ Y .....5 5 � . C' � 4 12 e70 i ^: • no C, • 1578 •� -65y � ��. •2015 '.iv ♦,4pz / \ ` - >1/ / ` `�•• +•-Jb n • LW-47 •y , \ • 1249 '4, • 121f ,1- i1A-4--4- 7 �, i. iiX} Qi i 11 :--7 •1216 . .L1. ••1 `2 i4 40, J`?+49'r} ,_.. C ♦�1 ., ;� r �•12ot.2 ._•1343.•- -iY rC -�L s — 16e✓i.� 1LW-54' �.•' 97 •1i77,' y7772 S`•‘� / 1 •. ...,ems ,..1757 il 14f •,"� •u9e 5 135 *992 Lw-21• • 1262\,,/ 64: ftje7 • rs • 12�5a ` 1 \ 9t10 • \ t� C • 1462,4.7 . .• h ,\`SO •ti •l07w1O4 \ • LW-62 ;' "N• •201 •` , ` • •1257 • 1014 .♦,40e ♦'1602 •1506 • 1 149 401 • • 1376/ x_ 041210 •1.,4 1., •/ ' . / 411114 •y15e • 1719 • •;1493, • • 1445 •1739 •4 Reference: Adapted from Plate 9, As -Graded Geotechnical Plan, Prepared by Leighton and Associates, dated 6/17/97, Project no. 892112-010, Base Map: Preliminary Grading Plan, Tract 15105, Planning Area 1 c-2, Newport Coast, Sheet 6B 0f 25 sheets, Hunsaker & Associates. Af EXPLANATION UNITS Manmade Fill SYMBOLS B-2 Boring Location COLEMAN GEOTECHNICAL 3002 DOW AVENUE, SUITE 414 TUSTIN, CALIFORNIA 92680 PHONE (714) 573-5776 FAX (714) 573-0438 GEOTECHNICAL PLAN JOE NO. DATL DR. BY /6 /8 r/i8 4 095' ii=