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HomeMy WebLinkAboutCT 02-27; La Costa Greens, Lots 4 and 5; Preliminary Geotechnical Evaluation; 2002-10-08o PRELIMINARY GEOTECHNICAL EVALUATION LA COSTA GREEN, LOTS 4 AND 5 V OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA FOR SCI ENTERPRISES, LLC 567 SAN NICOLAS DRIVE, SUITE 320 NFWDODT BCArMJ f+AI ie/M!»MIA nneen Geotechnical • Geologic • Environmental PRELIMINARY GEOTECHNICAL EVALUATION LA COSTA GREEN, LOTS 4 AND 5 CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA FOR SCI ENTERPRISES, LLC 567 SAN NICOLAS DRIVE, SUITE 320 NEWPORT BEACH, CALIFORNIA 92660 W.O. 3401 -A-SC OCTOBER 8, 2002 Geotechnical • Geologic • Environmental 5741 Palmer Way • Carlsbad, California 92008 • (760)438-3155 • FAX (760) 931-0915 October 8, 2002 W.O.3401-A-SC SCI Enterprises, LLC 567 San Nicolas Drive, Suite 320 Newport Beach, California 92660 Attention: Mr. Bret Shaves Subject: Preliminary Geotechnical Evaluation, La Costa Green, Lots 4 and 5, City of Carlsbad, San Diego County, California Dear Mr. Shaves: In accordance with your request, GeoSoils, Inc. (GSI) is pleased to present the results of our preliminary geotechnical evaluation on the subject site. The purpose of our investigation was to evaluate the geologic and geotechnical conditions of the site, relative to the proposed additions, and present recommendations for foundation design and construction based on our findings. EXECUTIVE SUMMARY Based on our field exploration, geologic and geotechnical engineering analysis, the proposed development appears feasible from a geotechnical and geologic viewpoint, provided that the recommendations presented herein are properly incorporated into the design and construction of the project. The most significant elements of our study are summarized below: • The subject site is underlain by artificial fill, which in turn is underlain by native formational sediments. A final compaction report of rough grading for the site could not be supplied nor acquired. • Based on our evaluation, including a review of the previous geotechnical report prepared by Testing Engineers of San Diego, Inc. (see Appendix B.TESD, 1988), the existing fill does not meet the current industry minimum relative compaction of 90 percent, is non-uniform, potentially compressible, and is therefore not suitable for the support of settlement sensitive improvements in its present condition. Removals onsite will consist of all existing artificial fill. Removal depths on the order of 5 feet to 11 feet should be anticipated. Groundwater was encountered at depth onsite, but is generally not anticipated to affect site development, providing that the recommendations contained in this report are incorporated into final design and construction, and that prudent surface and subsurface drainage practices are incorporated into the construction plans. Perched groundwater conditions along zones of contrasting permeability should not be precluded from occurring in the future due to site irrigation, poor drainage conditions, or damaged utilities. Should perched groundwater conditions develop, this office could assess the affected area(s) and provide the appropriate recommendations to mitigate the observed groundwater conditions. Our laboratory test results indicate that soils onsite are generally medium in expansion potential (expansion index range 51 to 90), per the 1997 UBC. Sulfate testing indicates that site soils present a severe exposure to concrete per Table 19- A-4 of the 1997 UBC (sample = 0.24 percent by weight). Corrosion testing (pH, resistivity) indicates that the soils are slightly acidic (pH = 5.9), but corrosive to ferrous metals (saturated resistivity = 435 ohms-cm). Alternative methods and additional comments should be obtained by a qualified corrosion engineer. Conventional foundation systems utilizing a slab-on-grade may likely be used onsite. Post-tension foundations may also be used. Based on our review, the site is expected to have a low risk to be affected by seismic hazards. The seismicity acceleration values provided herein should be considered during the design of the proposed development. The geotechnical design parameters provided herein should be considered during project planning design and construction by the project structural engineer and/or architects. SCI Enterprises, LLC W.0.3401 -A-SC File:e:\wp7\3400\3401a.pge Page Two GeoSoils, Inc. m M p b The opportunity to be of service is sincerely appreciated. If you should have any questions, please do not hesitate to contact our office. Respectfully submitt GeoSoils, Inc. /^ Robert G. Crisman Engineering Geologist Reviewed by: David W. Skelly Civil Engineer,RCI fB. Boehmer Staff Geologist RB/RGC/JPF/DWS/ki Distribution: (4) Lightfoot Planning Group, Attention: Ms. Alexis Pagnotta SCI Enterprises, LLC Rle:e:\wp7\3400\3401 a.pge W.O.3401-A-SC Page Three GeoSoils, Inc. TABLE OF CONTENTS SCOPE OF SERVICES 1 SITE DESCRIPTION AND PROPOSED DEVELOPMENT 1 PREVIOUS WORK 3 FIELD STUDIES 3 REGIONAL GEOLOGY 3 EARTH MATERIALS 4 Artificial Fill (Map Symbol - Af) 4 Santiago Formation (Not Mapped) 4 FAULTING AND REGIONAL SEISMICITY 4 Faulting 4 Seismicity 6 Seismic Shaking Parameters 7 Seismic Hazards 7 GROUNDWATER 8 LABORATORY TESTING 8 Laboratory Standard 8 Expansion Potential 9 Shear Testing 9 Consolidation Testing 9 Atterberg Limits 9 Corrosion/Sulfate Testing 9 DISCUSSION AND CONCLUSIONS 10 General 10 EXISTING FILL EVALUATION 10 EARTHWORK CONSTRUCTION RECOMMENDATIONS 11 General 11 Site Preparation 11 Removals (Unsuitable Surficial Materials) 11 Fill Placement 11 Slopes 12 GeoSoilSj Inc. RECOMMENDATIONS - FOUNDATIONS 12 General 12 Foundation Design 12 Foundation Construction 13 CONVENTIONAL RETAINING WALLS 14 General 14 Restrained Walls 15 Cantilevered Walls 15 Wall Backfill and Drainage 15 ADDITIONAL RECOMMENDATIONS/DEVELOPMENT CRITERIA 16 Tile Flooring 16 Gutters and Downspouts 16 Exterior Slabs and Walkways 16 Landscape Maintenance and Planting 17 Drainage 18 Footing Trench Excavation 18 Trench Backfill 18 FOOTING SETBACKS 19 PLAN REVIEW 19 INVESTIGATION LIMITATIONS 19 FIGURES: Figure 1 - Site Location Map 2 Figure 2 - California Fault Map 5 ATTACHMENTS: Appendix A - References Rear of Text Appendix B - Previous Report by TESD (1988) Rear of Text Appendix C - Boring Logs Rear of Text Appendix D - Laboratory Data Rear of Text Appendix E - General Earthwork and Grading Guidelines Rear of Text Plate 1 - Geotechnical Map Rear of Text in Pocket SCI Enterprises, LLC Table of Contents File:e:\wp7\3400\3401a.pge Page ii GeoSoils, Inc. PRELIMINARY GEOTECHNICAL EVALUATION LA COSTA GREEN, LOTS 4 AND 5, CITY OF CARLSBAD SAN DIEGO COUNTY, CALIFORNIA <* SCOPE OF SERVICES m The scope of our services has included the following: m 1. Review of readily available soils and geologic data (Appendix A). A copy of the m previous soils report, prepared by Testing Engineers of San Diego (TESD, 1998) is included in this report as Appendix B. m 2. Subsurface exploration consisting of the excavation of five exploratory borings with — a hollow stem auger drill rig, in the areas of proposed improvements, for geotechnical logging and sampling (Appendix C). m m 3. Laboratory testing of representative soil samples collected during our subsurface exploration program (text and Appendix D). IP M 4. Appropriate engineering and geologic analysis of data collected and preparation of this report.m m SITE DESCRIPTION AND PROPOSED DEVELOPMENT The subject site consists of two previously graded, vacant parcels located on the north side of La Costa Avenue, between 2320 and 2348 La Costa Avenue, in the City of Carlsbad, California (see Site Location Map, Figure 1). Existing condominium complexes border the site to the west and east; and a golf course and La Costa Avenue border the site to the north and south respectively. The property appears to be underlain by fill materials with fill slopes ranging from approximately 4 to 10 feet in height on the eastern end of the site, and cut slopes ranging from approximately 8 to 15 feet in height on the southern reaches of the property. The site appears to be at elevations ranging from approximately 20 to 40 feet mean sea level (MSL). Onsite vegetation consists of grasses, weeds and bushes. Drainage onsite appears to be directed offsite to the north, into San Marcos Creek. Site development is anticipated to consist of preparing the site for the construction of 10 residential condominium structures with underground parking and associated improvements. Building loads are assumed to be typical for this type of relatively light construction. Proposed site development is shown on the attached geotechnical map (Plate 1), which uses the 20-scale map prepared by O'Day Consultants as a base. GeoSoils, Inc. J DTopoQuwh Copyright* T999 Mamt Varmouth, ME M0% Source Data: USGS Base Map: Encinitas Quadrangle, California—San Diego Co., 7.5 Minute Series (Topographic), 1968 (photo revised 1975), by USGS, 1"=2000' 2000 Scale 4000 Feet W.O. 3401-A-SC SITE LOCATION MAP Figure 1 PREVIOUS WORK Based on the presence of existing artificial fill, graded building pads and slopes, it appears that the site has been previously graded. However, a compaction report of rough grading was not available for review. As such, the fill materials are undocumented. A previous geotechnical investigation was completed at the site by TESD in 1988, with the findings, conclusions and recommendations of their study presented in TESD (1988). Recommendations presented in TESD (1988) included the removal and recompaction of existing fill materials, for the support of planned structures. A partial copy of TESD (1988) is included in this report as Appendix B. FIELD STUDIES Field studies conducted by GSI consisted of advancing five exploratory hollow stem auger borings to depths ranging from 51/2 feet to 21 feet below existing grades, for evaluation of near-surface soil and geologic conditions. Borings were logged by a geologist from our firm who collected representative bulk and undisturbed samples for appropriate laboratory testing. Logs of the borings are presented in Appendix C. The locations of the borings are presented on the enclosed Geotechnical Map, Plate 1. REGIONAL GEOLOGY The subject property is located within a prominent natural geomorphic province in southwestern California known as the Peninsular Ranges. It is characterized by steep, elongated mountain ranges and valleys that trend northwesterly. The mountain ranges are underlain by basement rocks consisting of pre-Cretaceous metasedimentary rocks, Jurassic metavolcanic rocks, and Cretaceous plutonic rocks of the southern California batholith. In the San Diego region, deposition occurred during the Cretaceous period and Cenozoic era in the continental margin of aforearc basin. Sediments, derived from Cretaceous-age plutonic rocks and Jurassic-age volcanic rocks, were deposited into the narrow, steep, coastal plain and continental margin of the basin during the Eocene and early Miocene time. These rocks have been uplifted, eroded and deeply incised. During early Pleistocene time, a broad coastal plain was developed from the deposition of marine terrace deposits. During mid to late Pleistocene time, this plain was uplifted, eroded, and incised. Alluvial deposits have since filled the lower valleys, and young marine sediments are currently being deposited/eroded within coastal and beach areas. The site is generally underlain by Eocene-age sedimentary deposits. SCI Enterprises, LLC W.O. 3401 -A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401a.pge Page 3 GeoSoils, Inc. EARTH MATERIALS Earth materials encountered on the site consist of artificial fill and Eocene age sedimentary bedrock belonging to the Santiago Formation. Artificial Fill (Map Symbol - Aft Artificial fill was encountered in all borings, to depths ranging from approximately 5 to 11 feet below existing grades. Where encountered, artificial fill materials generally consisted of yellow brown to brown sandy clay to clayey sand. The materials were typically dry and loose near the surface, then become moist to wet and stiff/medium dense with increasing depth. Field density testing and laboratory testing indicate that existing fills are generally compacted to 84 to 89 percent relative compaction. Based on the relatively dry condition of near surface fill soils and relative compaction values determined to be less than the industry minimum standard of 90 percent, this material is non-uniform, potentially compressible, and is not considered suitable for structural support. The existing fill should be removed, moisture conditioned, and recompacted in areas support to settlement sensitive improvements. These findings are generally consistent with those presented in TESD (1988). Santiago Formation (Not Mapped! The Eocene age Santiago Formation underlies the site at depths on the order of 5 to 11 feet (this study and TESD, 1988) below existing grades. As encountered in our test excavations, this material generally consists of a brown to yellow brown silty/clayey sandstone and dark gray claystone. These materials are generally moist to wet and medium dense and stiff to very stiff. Bedding structure was observed to be generally flat lying. FAULTING AND REGIONAL SEISMICITY Faulting The site is situated in an area of active as well as potentially-active faults. Our review indicates that there are no known active faults crossing the site within the areas proposed for development (Jennings, 1994; Tan and Kennedy, 1996), and the site is not within an Earthquake Fault Zone (Hart and Bryant, 1997). There are a number of faults in the southern California area that are considered active and would have an effect on the site in the form of ground shaking, should they be the source of an earthquake. These include-but are not limited to-the San Andreas fault, the San Jacinto fault, the Elsinore fault, the Coronado Bank fault zone, and the Newport-lnglewood/Rose Canyon fault zone. The location of these and other major faults relative to the site are indicated on Figure 2. The possibility of ground acceleration or shaking at the site may be considered as approximately similar to the southern California region as a whole. SCI Enterprises, LLC W.O.3401-A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401a.pge Page 4 GeoSoils, Inc. SAN FRANCISCO SITE LOCATION ( + ): Latitude - 33.0875 N Longitude - 1 17.2593 W S.C.I. ENTERPRISES CALIFORNIA FAUL W.O. 3401-A-SC Figure 2 The following table lists the major faults and fault zones in southern California that could have a significant effect on the site should they experience significant activity. ABBREVIATED FAULT NAME Coronado Bank - Agua Blanca Elsinore La Nacion Newport-lnglewood-Offshore Rose Canyon San Diego Trough-Bahia Sol APPROXIMATE DISTANCE MILES (KM) 21 (34) 25 (40) 18 (29) 12(19) 6(10) 32J51) Seismicitv The acceleration-attenuation relations of Joyner and Boore (1982a, 19825), Campbell and Bozorgnia (1994), and Sadigh and others (1989) have been incorporated into EQFAULT (Blake, 1997). For this study, peak horizontal ground accelerations anticipated at the site were determined based on the random mean plus 1 - sigma attenuation curves developed by Joyner and Boore (1982a, 1982b), Campbell and Borzorgnia (1994), and Sadigh and others (1989). These acceleration-attenuation relations have been incorporated in EQFAULT, a computer program by Thomas F. Blake (1997), which performs deterministic seismic hazard analyses using up to 150 digitized California faults as earthquake sources. The program estimates the closest distance between each fault and a user-specified file. If a fault is found to be within a user-selected radius, the program estimates peak horizontal ground acceleration that may occur at the site from the upper bound ("maximum credible") and "maximum probable" earthquakes on that fault. Site acceleration (g) is computed by any of the 14 user-selected acceleration-attenuation relations that are contained in EQFAULT. Based on the above, peak horizontal ground accelerations from an upper bound event may be on the order of 0.44 g to 0.64 g, and a maximum probable event may be on the order of 0.29 g to 0.35 g. SCI Enterprises, LLC La Costa Green, Carlsbad File:e:\wp7\3400\3401a.pge W.O.3401-A-SC October 8, 2002 Page 6 GeoSoils, Inc. Seismic Shaking Parameters Based on the site conditions, Chapter 16 of the Uniform Building Code (International Conference of Building Officials, 1997), the following seismic parameters are provided: Seismic zone (per Figure 16-2*) Seismic Zone Factor (per Table 16-1*) Soil Profile Type (per Table 1 6-J*) Seismic Coefficient Ca (per Table 16-Q*) Seismic Coefficient Cv (per Table 16-R*) Near Source Factor Na (per Table 16-S*) Near Source Factor Nv (per Table 1 6-T*) Seismic Source Type (per Table 16-U*) Distance to Seismic Source Upper Bound Earthquake 4 0.40 SD 0.44 Na 0.64 Nv 1.0 1.0 B 6 mi (10km) MW6.9 * Figure and table references from Chapter 1 6 of the Uniform Building Code (1 997). Seismic Hazards The following list includes other seismic related hazards that have been considered during our evaluation of the site. The hazards listed are considered negligible and/or completely mitigated as a result of site location, soil characteristics and typical site development procedures: • Liquefaction • Dynamic Settlement • Surface Fault Rupture • Ground Lurching or Shallow Ground Rupture • Tsunami It is important to keep in perspective that in the event of a maximum probable or credible earthquake occurring on any of the nearby major faults, strong ground shaking would occur in the subject site's general area. Potential damage to any structure(s) would likely be greatest from the vibrations and impelling force caused by the inertia of a structure's mass, than from those induced by the hazards considered above. This potential would be no greater than that for other existing structures and improvements in the immediate vicinity. SCI Enterprises, LLC La Costa Green, Carlsbad File:e:\wpA3400\3401 a.pge W.O.3401-A-SC October 8,2002 Page? GeoSoils, Inc. GROUNDWATER Based on a review of TESD (1988) and the results of this study, a perched groundwater table is present at a depth of approximately 20 feet to 27 feet below existing grades. Groundwater was not observed within bedrock materials encountered below these depths (TESD, 1988). Subsurface water is not anticipated to adversely affect site development, provided that the recommendations contained in this report are incorporated into final design and construction. These observations reflect site conditions at the time of our investigation and do not preclude future changes in local groundwater conditions from excessive irrigation, precipitation, or that were not obvious, at the time of our investigation. Seeps, springs, or other indications of a high groundwater level were not noted on the subject property during the time of our field investigation. However, seepage may occur locally (due to heavy precipitation or irrigation) in areas where fill soils overlie bedrock deposits. The regional water table is estimated to be at least 60 feet to 100 feet below existing grade. LABORATORY TESTING Laboratory tests were performed on a representative sample of representative site earth materials in order to evaluate their physical characteristics. Test procedures used and results obtained are presented below. Laboratory Standard The maximum density and optimum moisture content was determined for the major soil type encountered in the borings. The laboratory standard used was ASTM D-1557. The moisture-density relationship obtained for this soil is shown in the following table: LOCATION B-1 @ 0-5' SOIL TYPE Sandy Clay, Yellow Brown MAXIMUM DENSITY (PCF) 121.0 OPTIMUM MOISTURE CONTENT (%) 13.5 SCI Enterprises, LLC W.O. 3401-A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401a.pge Page 8 GeoSoils, Inc. Expansion Potential Expansion testing was performed on representative samples of site soil in accordance with UBC Standard 18-2 (UBC, 1997). The results of expansion testing are presented in the following table: LOCATION B-1 @ 0-5' EXPANSION INDEX 73 EXPANSION POTENTIAL Medium Shear Testing Shear testing was performed on a representative, "undisturbed" sample of site soil (B-1 @ 2 feet) in general accordance with ASTM test method D-3080 in a Direct Shear Machine of the strain control type. The shear test results are presented in the following table: SAMPLE LOCATION B-1 @ 0-5' (remolded) PRIMARY COHESION (PSF) 1400 FRICTION ANGLE (DEGREES) 26 RESIDUAL COHESION (PSF) 1450 FRICTION ANGLE (DEGREES) 24 Consolidation Testing Consolidation tests were performed on selected undisturbed samples. Testing was performed in general accordance with ASTM test method D-2435. Test results are presented in Appendix D. Atterberg Limits Atterberg Limits, i.e., Plasticity Limit, Plastic Index and Liquid Limit, were determined for a representative sample of site soil in general accordance with ASTM D-4318. Test results are presented in Appendix D. Corrosion/Sulfate Testing Sulfate testing indicates that site soils have a severe exposure to concrete per Table 19-A-4 of the 1997 UBC (water extractable sulfate = 0.0237 percent by weight), therefore, the use SCI Enterprises, LLC La Costa Green, Carlsbad File:e:\wp7\3400\3401 a.pge W.O.3401-A-SC October 8, 2002 Page9 GeoSofls, Inc. of Type V cement should be anticipated. Corrosion testing (pH, resistivity) indicates that soils are slightly acidic (pH = 5.9); and appear to be corrosive (saturated resistivity = 435 ohms-cm) to ferrous metals. As such, a corrosion engineer should be consulted. Test results are presented in Appendix D. DISCUSSION AND CONCLUSIONS General Based on our field exploration, laboratory testing and geotechnical engineering analysis, it is our opinion that the subject site appears suitable for the proposed additions from a geotechnical engineering and geologic viewpoint, provided that the recommendations presented in the following sections are incorporated into the design and construction phases of site development. The primary geotechnical concerns with respect to the proposed development and improvements are: Earth materials characteristics and depth to competent bearing material. Potential for settlement. The quality of the existing fill. Expansion and corrosion potential of site soils. Subsurface water and potential for perched water. Regional seismic activity. The recommendations presented herein consider these as well as other aspects of the site. In the event that any significant changes are made to proposed site development, the conclusions and recommendations contained in this report shall not be considered valid unless the changes are reviewed and the recommendations of this report verified or modified in writing by this office. Foundation design parameters are considered preliminary until the foundation design, layout, and structural loads are provided to this office for review. EXISTING FILL EVALUATION As indicated in the "laboratory testing" section, GSI performed in-situ moisture and density testing of the existing fill. The fill tested appears to have relative compactions on the order of 84 to 89 percent. As indicated previously, the fill does not appear to meet the minimum industry standard of 90 percent relative compaction. Due to the relative age, non-uniformity, lack of documentation, low relative compaction and changes in standards of practice since the fill was initially placed, it is our opinion that the existing fill does not meet the current standards of practice, is not suitable for the support of structures or other settlement sensitive improvements, and should be removed and recompacted. SCI Enterprises, LLC W.O. 3401 -A-SC La Costa Green, Carlsbad October 8,2002 Rle:e:\wp7\3400\3401a.pge Page 10 GeoSoils, Inc. EARTHWORK CONSTRUCTION RECOMMENDATIONS General All grading should conform to the guidelines presented in Appendix Chapter A33 of the Uniform Building Code, the requirements of the City of Carlsbad, the requirements of the County of San Diego, as presented in the text of this report and Appendix E. Prior to grading, a GSI representative should be present at the preconstruction meeting to provide additional grading guidelines, if needed, and review the earthwork schedule. During earthwork construction all site preparation and the general grading procedures of the contractor should be observed and the fill selectively tested by a representative(s) of GSI. If unusual or unexpected conditions are exposed in the field, they should be reviewed by this office and if warranted, modified and/or additional recommendations will be offered. All applicable requirements of local and national construction and general industry safety orders, the Occupational Safety and Health Act, and the Construction Safety Act should be met. Site Preparation All debris, vegetation and other deleterious material should be removed from the building area prior to the start of construction. Sloping areas to receive fill should be properly benched in accordance with current industry standards of practice and guidelines specified in the Uniform Building Code. Removals (Unsuitable Surficial Materials) Removals should consist of all existing fill material in areas proposed for settlement sensitive structures or areas to receive compacted fill. At this time, removal depths on the order of 5 feet to 11 feet should be anticipated; however, locally deeper removals may be necessary. Removals should be completed below a 1:1 projection down and away from the edge of existing structures on adjacent properties. Once removals are completed, the exposed bottom should be reprocessed and compacted. Fill Placement Subsequentto ground preparation, onsite soils may be placed in thin (±6-inch) lifts, cleaned of vegetation and debris, brought to a least optimum moisture content, and compacted to achieve a minimum relative compaction of 90 percent. If soil importation is planned, a sample of the soil import should be evaluated by this office prior to importing, in order to assure compatibility with the onsite site soils and the recommendations presented in this report. Import soils should be low expansive (expansion index [E.I.] less than 50). SCI Enterprises, LLC W.O. 3401 -A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401a.pge Page 11 GeoSoils, Inc. Slopes Graded slopes constructed to maximum anticipated heights on the order of 15 feet, or less, are anticipated to be grossly and surficially stable, provided that slope are designed and constructed in accordance with the recommendations presented in this report. RECOMMENDATIONS - FOUNDATIONS General In the event that the information concerning the proposed development plan is not correct, or any changes in the design, location or loading conditions of the proposed structure are made, the conclusions and recommendations contained in this report shall not be considered valid unless the changes are reviewed and conclusions of this report are modified or approved in writing by this office. It is our understanding that slab-on-grade construction is desired for the proposed development. In addition to this type of floor construction, a raised wood floor may also be considered. The information and recommendations presented in this section are not meant to supersede design by the project structural engineer. Upon request, GSI could provide additional input/consultation regarding soil parameters, as related to foundation design. Foundation Design 1. Conventional spread and continuous footings may be used to support the proposed residential structure provided they are founded entirely in properly compacted fill or other competent bearing material (i.e., Santiago Formation). Footings should not simultaneously bear directly on Santiago Formation and fill soils. 2. Analyses indicate that an allowable bearing value of 1,500 pounds per square foot may be used for design of continuous footings 18 inches deep by 15 inches wide, and design of isolated pad footings 24 inches square and 18 inches deep into properly compacted fill or terrace. The bearing value may be increased by one-third for seismic or other temporary loads. This value may be increased by 20 percent for each additional 12 inches in depth, to a maximum of 2,500 pounds per square foot. 3. For lateral sliding resistance, a 0.35 coefficient of friction may be utilized for a concrete to soil contact when multiplied by the dead load. 4. Passive earth pressure may be computed as an equivalent fluid having a density of 250 pounds per cubic foot with a maximum earth pressure of 2,500 pounds per square foot. SCI Enterprises, LLC W.O. 3401 -A-SC La Costa Green, Carlsbad October 8,2002 Rle:e:\wp7\3400\3401a.pge Page 12 Inc. 5. When combining passive pressure and frictional resistance, the passive pressure component should be reduced by one-third. 6. Footings should maintain a horizontal distance or setback between any adjacent slope face and the bottom outer edge of the footing. The horizontal distance may be calculated by using h/3, where (h) is the height of the slope. The horizontal setback should not be less than 7 feet, nor need not be greater than 40 feet (per code). The setback may be maintained by simply deepening the footings. Flatwork, utilities or other improvements within a zone of h/3 from the top of slope may be subject to lateral distortion. Footings, flatwork, and utilities setbacks should be constructed in accordance with distances indicated in this section, and/or the approved plans. 7. Provided that the recommendations contained in this report are incorporated into final design and construction phase of development, a majority (>50 percent) of the anticipated foundation settlement is expected to occur during construction. Maximum settlement is not expected to exceed approximately 1/2 inch and should occur below the heaviest loaded columns. Differential settlement is not anticipated to exceed 1 inch between similar elements, in a 40-foot span. Foundation Construction 1. Conventional continuous footings may be constructed per UBC guidelines regarding width and a minimum of 18 inches deep for medium expansive soils. Foundations should be founded at least 18 inches into suitable native soil. Footings should be reinforced with four No. 4 reinforcing bars, two placed near the top, and two placed near the bottom of the footing. 2. Detached isolated interior or exterior piers and columns should be founded at a minimum depth of 24 inches (medium expansive), below the lowest adjacent ground surface and tied to the main foundation in at least one direction with a grade beam. Reinforcement should be properly designed by the project structural engineer. 3. A grade beam, reinforced as above, and at least 12 inches square, should be provided across the garage entrances. The base of the reinforced grade beam should be at the same elevation as base of the adjoining footings. 4. The residential floor and garage slabs should have a minimum thickness of 4 inches. Concrete used in floor slab construction should have a minimum compressive strength of 2,500 psi. For preliminary design purposes, the use of Type V cement (severe sulfate exposure) should be anticipated. This will be verified at the completion of site grading. 5. Concrete slabs should be underlain with a minimum of 4 inches of sand. In addition, a vapor barrier consisting of a minimum of 10-mil, polyvinyl-chloride membrane, with all laps sealed, should be provided at the mid-point of the sand layer. The slab SCI Enterprises, LLC W.O. 3401-A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401 a.pge Page 13 GeoSoils, Inc. subgrade should be free of loose and uncompacted material prior to placing concrete. 6. Concrete floor slabs should be minimally reinforced with No. 3 reinforcing bars placed 18 inches on center each way. All slab reinforcement should be supported to ensure proper mid-slab height positioning during placement of the concrete. "Hooking" of reinforcement is not an acceptable method of positioning. 7. The moisture content of the subgrade soils should be greater than optimum moisture to a depth of 18 inches below the adjacent ground grade in the slab areas for low expansive soil conditions. Soil moistures should be verified by this office within 72 hours of the vapor barrier placement. 8. Soils generated from footing excavations to be used onsite should be compacted to a minimum relative compaction of 90 percent of the laboratory standard, whether it is to be placed inside the foundation perimeter or in the yard/right-of-way areas. This material must not alter positive drainage patterns that direct drainage away from the structural areas and toward the street. 9. As an alternative, an engineered post-tension foundation system may be used. Recommendations for post-tensioned slabs can be provided on request. CONVENTIONAL RETAINING WALLS General Foundations may be designed using parameters provided in the "Design" section of Foundation Recommendations presented herein. Wall sections should adhere to the County of San Diego guidelines. All wall designs should be reviewed by a qualified structural engineer for structural capacity, overturning and stability. The design parameters provided assume that onsite or equivalent medium expansive soils or selected fill are used to backfill retaining walls. If expansive soils are used to backfill the proposed walls within this wedge, increased active and at-rest earth pressures will need to be utilized for retaining wall design. Heavy compaction equipment should not be used above a 1:1 projection up and away from the bottom of any wall. The following recommendations are not meant to apply to specialty walls (cribwalls, loffel, Keystone, etc.). Recommendations for specialty walls will be greater than those provided herein, and can be provided upon request. Some movement of the walls constructed should be anticipated as soil strength parameters are mobilized. This movement could cause some cracking dependent upon the materials used to construct the wall. To reduce wall cracking due to settlement, walls should be internally grouted and/or reinforced with steel. SCI Enterprises, LLC W.O. 3401-A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401a.pge Page 14 GeoSoils, Inc. Restrained Walls Any retaining walls that will be restrained prior to placing and compacting backfill material or that have re-entrant or male corners, should be designed for an at-rest equivalent fluid pressures of 78 pcf for native soil backfill, plus any applicable surcharge loading. The equivalent fluid pressure can be reduced to 62 pcf if a selected backfill material of friction angle 30 degrees is used. For areas of male or re-entrant corners, the restrained wall design should extend a minimum distance of twice the height of the wall laterally from the corner. Building walls below grade, should be water-proofed or damp-proofed, depending on the degree of moisture protection desired. Refer to the following section for preliminary recommendations from surcharge loads. Cantilevered Walls These recommendations are for cantilevered retaining walls up to 15 feet high. Active earth pressure may be used for retaining wall design, provided the top of the wall is not restrained from minor deflections. An empirical equivalent fluid pressure (EFP) approach may be used to compute the horizontal pressure against the wall. Appropriate fluid unit weights are provided for specific slope gradients of the retained material. These do not include other superimposed loading conditions such as traffic, structures, seismic events or adverse geologic conditions. SURFACE SLOPE OF RETAINED MATERIAL HORIZONTAL TO VERTICAL Level 2 to 1 (H:V) EQUIVALENT FLUID UNIT WEIGHT P.C.F. (Native soil) 48 62 EQUIVALENT FLUID UNIT WEIGHT P.C.F. (Fill with Phi=30) 40 55 The equivalent fluid density should be increased to 75 pounds per cubic foot for level backfill using the native soil at the angle point of the wall (corner or male re-entrant) and extended a minimum lateral distance of 2H (two times the wall height) on either side of the corner. However if the select backfill with angle of friction of 30 degrees is used, this value may be reduced to 62 pounds per cubic foot. Wall Backfill and Drainage All retaining walls should be provided with an adequate gravel and pipe backdrain and outlet system (a minimum two outlets per wall), to prevent buildup of hydrostatic pressures and be designed in accordance with minimum standards presented herein. Pipe should consist of schedule 40 perforated PVC pipe. Gravel used in the backdrain systems should be a minimum of 3 cubic feet per lineal foot of 3/a- to 1 Va-inch clean crushed rock encapsulated in filter fabric (Mirafi 140 or equivalent). Perforations in pipe should face down. The surface SCI Enterprises, LLC La Costa Green, Carlsbad File:e:\wp7\3400\3401 a.pge W.O.3401-A-SC October 8,2002 Page 15 GeoSoils, Inc. of the backfill should be sealed by pavement or the top 18 inches compacted to 90 percent relative compaction with native soil. Proper surface drainage should also be provided. As an alternative to gravel backdrains, panel drains (Miradrain 6000, Tensar, etc.) may be used. Panel drains should be installed per manufacturers guidelines. Regardless of the backdrain used, walls should be water proofed where they would impact living areas or where staining would be objectionable. ADDITIONAL RECOMMENDATIONS/DEVELOPMENT CRITERIA Tile Flooring Tile flooring can crack, typically reflecting cracks in the concrete slab below the tile. Therefore, the designer should consider additional steel reinforcement of concrete slabs on- grade where tile will be placed. The tile installer should consider installation methods that reduce possible cracking of the tile such as slipsheets. Slipsheets or a vinyl crack isolation membrane (approved by the Tile Council of America/Ceramic Tile Institute) is recommended between tile and concrete slabs on grade. Gutters and Downspouts Consideration should be given to the installation of gutters and downspouts to collect roof water that may otherwise infiltrate the soils adjacent to the structures. The downspouts should be drained away from the foundation and collected in drainage swales or other approved non-erosive drainage systems designed by a registered civil engineer (specializing in drainage) to convey water away from the foundation. Gutters and downspouts are not a geotechnical requirement, however, provided positive drainage is maintained in accordance with the recommendations of the design civil engineer. Exterior Slabs and Walkways Exterior concrete slab on grade construction should be designed and constructed in accordance with the following criteria: 1. Driveway pavement and all other exterior flatwork should be a minimum of 4 inches thick. A thickened edge (12 inches) should be considered for all flatwork adjacent to irrigated and landscape areas. 2. Slab subgrade should be scarified, moisture conditioned, and compacted to a minimum 95 percent relative compaction for driveways and 90 percent for walkways. Subgrade should be moisture conditioned based on the representative expansion potential of the subgrade exposed (i.e., at least optimum moisture content). The subgrade moisture content should be maintained until the slab is poured. SCI Enterprises, LLC W.0.3401 -A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401 a.pge Page 16 GeoSoils, Inc. 3. The use of transverse and longitudinal control joints should be considered to help control slab cracking due to concrete shrinkage or expansion. Two of the best ways to control this movement is: 1) add a sufficient amount of reinforcing steel, increasing tensile strength of the slab; and/or 2) provide an adequate amount of control and/or expansion joints to accommodate anticipated concrete shrinkage and expansion. We would suggest that the maximum control joint spacing for un-reinforced slabs be placed on 8-foot centers (4-inch slab), 10-foot centers (5-inch slab) or the smallest dimension of the slab, whichever is least. 4. No traffic should be allowed upon the newly poured concrete slabs until they have been properly cured to within 75 percent of design strength. 5. Positive site drainage should be maintained at all times. Adjacent landscaping should be graded to drain into an approved area. All surface water should be appropriately directed to areas designed for site drainage. 6. Concrete compression strength should be a minimum of 2,500 psi. Landscape Maintenance and Planting Water has been shown to weaken the inherent strength of soil, and slope stability is significantly reduced by overly wet conditions. Positive surface drainage away from graded slopes should be maintained and only the amount of irrigation necessary to sustain plant life should be provided for planted slopes. Over-watering should be avoided. Onsite soil materials should be maintained in a solid to semisolid state. Brushed native and graded slopes (constructed within and utilizing onsite materials) would be potentially erosive. Eroded debris may be minimized and surficial slope stability enhanced by establishing and maintaining a suitable vegetation cover soon after construction. Plants selected for landscaping should be lightweight, deep rooted types that require little water and are capable of surviving the prevailing climate. Planting of large trees with potential for extensive root development should not be placed closer than 10 feet from the perimeter of the foundation or the anticipated height of the mature tree, whichever is greater. In order to minimize erosion on the slope face, an erosion control fabric (i.e., jute matting) should be considered. From a geotechnical standpoint, leaching is not recommended for establishing landscaping. If the surface soils area is processed for the purpose of adding amendments, they should be recompacted to 90 percent minimum relative compaction. Moisture sensors, embedded into fill slopes, should be considered to reduce the potential of overwatering from automatic landscape watering systems. The use of certain fertilizers may affect the corrosion characteristics of soil. Review of the type and amount (pounds per acre) of the fertilizers by a corrosion specialist should be considered. SCI Enterprises, LLC W.0.3401 -A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401a.pge Page 17 GeoSoils, Inc. Recommendations for exterior concrete flatwork design and construction can be provided upon request. If in the future, any additional improvements are planned for the site, recommendations concerning the geological or geotechnical aspects of design and construction of said improvements could be provided upon request. This office should be notified in advance of any additional fill placement, regrading of the site, or trench backfilling after rough grading has been completed. This includes any grading, utility trench, and retaining wall backfills. Drainage Positive site drainage should be maintained at all times. Drainage should not flow uncontrolled down any descending slope. Water should be directed away from foundations and not allowed to pond and/or seep into the ground. Pad drainage should be directed toward the street or other approved area. Landscaping should be graded to drain into the street, or other approved area. All surface water should be appropriately directed to areas designed for site drainage. Roof gutters and down spouts should be considered to control roof drainage. Down spouts should outlet a minimum of 5 feet from proposed structures or tightlined into a subsurface drainage system. We recommend that any proposed open bottom planters adjacent to proposed structures be eliminated for a minimum distance of 1 0 feet. As an alternative, closed bottom type planters could be utilized. An outlet placed in the bottom of the planter, could be installed to direct drainage away from structures or any exterior concrete flatwork. Drainage behind top of walls should be accomplished along the length of the wall with a paved channel drainage v-ditch or substitute. Footing Trench Excavation All footing trench excavations should be observed and approved by a representative of this office prior to placing reinforcement. Footing trench spoil and any excess soils generated from utility trench excavations should be compacted to a minimum relative compaction of 90 percent, if not removed from the site. Trench Backfill All excavations should be observed by one of our representatives and conform to OSHA and local safety codes. Exterior trenches should not be excavated below a 1 :1 projection from the bottom of any adjacent foundation system. If excavated, these trenches may undermine support for the foundation system potentially creating adverse conditions. 1 . All utility trench backfill in slopes, structural areas and beneath hardscape features should be brought to near optimum moisture content and then compacted to obtain a minimum relative compaction of 90 percent of the laboratory standard. Observations, probing and, if deemed necessary, testing should be performed by a representative of this office to verily compactive efforts of the contractor. SCI Enterprises, LLC W.O.3401-A-SC La Costa Green, Carlsbad October 8, 2002 File:e:\wp7\3400\3401 a.pge Page 1 8 GeoSotls, Inc. 2. Soils generated from utility trench excavations should be compacted to a minimum of 90 percent (ASTM D-1557) if not removed from the site. 3. Jetting of backfill is not recommended. 4. The use of pipe jacking to place utilities is not recommended on this site due to the presence of gravels and cobbles. 5. Bottoms of utility trenches should be sloped away from structures. FOOTING SETBACKS All footings should maintain a minimum 7-foot horizontal setback from the base of the footing to any descending slope. This distance is measures from the footing face at the bearing elevation. Footings should maintain a minimum horizontal setback of H/3 (H=slope height) from the base of the footing to the descending slope face and no less than 7 feet nor need to be greater than 40 feet. Footings adjacent to unlined drainage swales should be deepened to a minimum of 6 inches below the invert of the adjacent unlined swale. PLAN REVIEW Final project plans should be reviewed by this office prior to construction, so that construction is in accordance with this report. Based on our review, supplemental recommendations and/or further geotechnical studies may be warranted. INVESTIGATION LIMITATIONS Inasmuch as our study is based upon the site materials observed, selective laboratory testing and engineering analysis, the conclusions and recommendations are professional opinions. These opinions have been derived in accordance with current standards of practice, and no warranty is expressed or implied. Standards of practice are subject to change with time. These opinions have been derived in accordance with current standards of practice, and no warranty is expressed or implied. Standards of practice are subject to change with time. GSI assumes no responsibility or liability for work or testing performed by others, for our scope-of-work was expressly limited to the evaluation of the sediments/soils underlying the proposed residence. In addition, this report may be subject to review by the controlling authorities. SCI Enterprises, LLC W.0.3401 -A-SC La Costa Green, Carlsbad October 8,2002 File:e:\wp7\3400\3401a.pge Page 19 GeoSoils, Inc. APPENDIX A REFERENCES APPENDIX A REFERENCES Blake, Thomas F., 1997, EQFAULT computer program and users manual for the deterministic prediction of horizontal accelerations from digitized California faults. Campbell, K.W., 1994, Empirical prediction of near-source ground motion from large earthquakes, ]n Johnson, J.A., Campbell, K.W., and Blake, eds., T.F., AEG Short Course, Seismic Hazard Analysis, June 18. Greensfelder, R. W., 1974, Maximum credible rock acceleration from earthquakes in California: California Division of Mines and Geology, Map Sheet 23. Hart, E.W. and Bryant, W.A., 1997, Fault-rupture hazard zones in California: California Department of Conservation, Division of Mines and Geology, Special Publication 42. Housner, G. W., 1970, Strong ground motion in earthquake engineering, Robert Wiegel, ed., Prentice-Hall. International Conference of Building Officials, 1997, Uniform building code: Whittier, California. Jennings, C.W., 1994, Fault activity map of California and adjacent areas: California Division of Mines and Geology, Map Sheet No. 6, scale 1:750,000. Joyner, W.B, and Boore, D.M., 1982a, Estimation of response-spectral values as functions of magnitude, distance and site conditions, ]n Johnson, J.A., Campbell, K.W., and Blake, eds., T.F., AEG Short Course, Seismic Hazard Analysis, June 18,1994. , 1982b, Prediction of earthquake response spectra, ]n Johnson, J.A., Campbell, K.W., and Blake, eds., T.F., AEG Short Course, Seismic Hazard Analysis, June 18,1994. Sadigh, K., Egan, J., and Youngs, R., 1989, Predictive ground motion equations reported in Joyner, W.B., and Boore, D.M., "Measurement, characterization, and prediction of strong ground motion", ]n Earthquake Engineering and Soil Dynamics II, Recent Advances in Ground Motion Evaluation, Von Thun, J.L, ed.: American Society of Civil Engineers Geotechnical Special Publication No. 20, pp. 43-102. Sowers and Sowers, 1970, Unified soil classification system (after U. S. Waterways Experiment Station and ASTM 02487-667) in Introductory Soil Mechanics, New York. Tan, S.S., and Kennedy, Michael P., 1996, Geologic maps of the northwestern part of San Diego County, California: California Division of Mines and Geology, Open File Report 96-02. GeoSoils, Inc. APPENDIX B PREVIOUS REPORT BY TESD (1988) TABLE OF CONTENTS INTRODUCTION 1 PROJECT DESCRIPTION 1 PROJECT DEVELOPMENT 1 PROJECT SCOPE 1i FIELD EXPLORATION 2 GEOTECHHICAL CONDITIONS 3 REGIONAL QEOLOOT 3 SUBSURFACE CONDITIONS.... 3 FAULTING AND SEISMICITT * LABORATORY TESTING... , 4 CLASSIFICATION „... * HDISTURE/DEN5ITT 5 SHEAR TESTS 5 LABORATORY STANDARD,.,.. S EXPANSION INDEX 6 CONCLUSIONS ... 6 RECOMMENDATIONS .*. \ FOUNDATION DESIGN AMD CONSTRUCTION 9 FOOTINGS 9ALLOWABLE BEARING CAPACITY 11 RETAINING WALLS 11 DRAINS 12 REVIEW 12 INVESTIGATION LIMITATIONS 14 ENCLOSURES; SITE LOCATION NAP FIGURE 1 BORING LOCATION HAP FIGURE 2 BORING LOGS ;..... PLATES 1-8 SYMBOLS AND TERMS USED ON BORING LOGS. PLATE 9 UNIFIED SOIL CLASSIFICATION PLATE 10 CONSOLIDATION CURVES PLATES 11-12 SHEAR TEST RESULT..... - PLATE 13 B-1 G4otechnical Investigation Hay 24, 1988Proposed Condosjiniua coaplex jo& NO. 7361La Co*t«i California mitODUCTIOM PROJECT PS3CKIPTIOII Our investigation was perforead at the »ite of the proposed two- stcry condominium aoaplox, leoaUd on tho northern aide of La Coata Avenu«, in CarleDad, California. Plaiae rarer to the Site Looatlon Hap, Figure 1. PKOJICT DEVELOPMENT The aite is to be developed with the eonatruetioit of aeveral two- atory« wood fraae, atuono exterior builaingi of al«b«on-grBda deaicn. laenitlaa will include parking areaa ana landaeaped grounoa. PBOJECT acopg Thta inve»ti(atlon eonciated oft aurfaee reeognixanoe, Bubtur^aoa explorations, obtaining representative diaturbed and undiBturbett aanplea( laboratory te»ting, analysts of field and laboratory data« and preparation of our report. This report oontaina 'our conclusions ana reooaejendationa and the results of our field and laboratory data. Specifically, the intent of this study la tos a) Explore the subsurface «onditions to the depths noted on the boring logs* B-2 Geoteehnioal Investigation Kay a«, 1986Proposed Condominium Complex Job Mo. 7361La Coata, California Page 2 b) Evaluate, By laboratory taata ana the field inveatigntioa, the parttnant engineering propertiea of the various atrata which will influence the davolopaent, inoluding their bearing capacities, expanaive eharaetariatioa and settlement potential* e) Develop aoil engineering criteria for alt a grading. d) Reoonaena en appropriate foundation eysten for the propoaad two-atory condominium buildinga and develop aoil engineering design criteria for the recommended foundation design. PIELP Subaurfaee donditiona were explored by drilling B-inch diameter borlnga with e Beaver Mobile drill rig- Boring locations are •hown on the Site Flan, Figure 2, end ranged in depth fro* 21.5 to 66.5 feet. Loga of the boringa are preoented on Flatea t through I. A geologist froa our office wee preaant during the drilling of the boringa to log aateriala encountered end to obtain repreaentatlve eaaplea at aeleetad depths for • tranaportation to our laboratory. Saaplea consisted of relatively undiaturbed aaterial collected In one-lneh^high, 2.37- inch-inaide-dlaneter rings* bag* and bulk aanplea. The ring aaaplea were collected by driving tha aaapler eighteen inehea Into the aoil by eoaaeoutive thirty-inch drops with a one- G«otechnical Investigation fay gf, 1988 Proposea Condoainiua Complex job tto. 7361La Coata, California Peg* 3 hundred-forty-pound heaaer. In the eeee of the standard two-Inch dlanater »ampler, the number of blova required to a«hiave the final twelve inehea of penetration la referreo to •» the •N- valuo* of the Standard Penetration Toat (8PT). Tbia' value providea a ameauro of aoil atrength and bearing aopaeity, ea It related to the aoil coaaiatenoy or condition. It la defined on the Syaoola and Teraa Chart (Plate 9) and uaed on the boring loga. GEOTlCHIIICaL COHDITIOM3 •EOIOIHt QEOLOQT The aubjeet aite ia aituateo in the lowland area of the Peninaula Range Geo«orphlO frovinee. The aite la underlain by reoent alluvlua oonaiatint of unoonaolidated streaa, river channel, and alluvial fan depoaita* Interbedded peat and lagoontl d«ooalta ere oonmonly found in theae fornationa. flUBSUKFACZ COMDITIDH3 All four bore holea eonalated of an andlfferentiated con* of fill aoil to depths Of 8-11 feet. This aoil aonaieted of oedoretely expansive (ray aandy alaya. Underlying thl«, up to the deptna •inveatlgatetf, were Intaralnglad layers of aandy o'lay and organio elay with aand l«na. B-4 Oeotaohnloal Inveatigatien Hay 24, 1988 Proposed Condoainiuo Coaplex Job No. 7361La Costa, California pwge n Groundwater ya* not encountered in the boring* to • depth of 66.5 feet at the tine of our field investigation. However, perched water Mia encountered ID Boring* 1, 2 ana *.. IMP Sol a ale hazard* within tb« aita aay b« attributed to ground •baking raaulting from avonta on distant, active faults* Liated on Table 1 are the aotiire fault* in tbe arae which nay aignifloently affect the site. TABLE 1 SEISMICITt FOK HAJOH FAULTS Diet. Haximtn Credible Predominate From Probable Bedrock Period In Activity Fault _ Site larthquake Acceleration aejcond* Rating Roae Canyon 12 BI. 7.0 0.35S .35 Seconds Aotive Fault ZoneNewport 15 •!. 6.75 0.35| .35 Second* Aotive Znglewood After Inveatigating the poaaible earthquake acceleration* of the alte, in our opinion, an event en either fault cone would be aignificant. Deaign of atruaturej should oomply with the requireaenta of the governnent agenaiea, building codes and atandard praeticea of the Aaaoolation of Structural gngineera of California. L1BOBATOHT TISTIKC Soil* were viaually elaaaified according to the Unified Soil B-5 Gaobechnlaal Inveabigation May 2«l, 1968 Proposed Condominium Complex job No. 7361 La Coata, California Page 5 Classification System aa presented on Plata 10. Soil olaaelflaatians are also •houn on the boring logs. HOI3TUKE/PEK3IT7 The field aolatura content and dry unit weight determined for aalaatad undlaturb«d aoll aamplea obtained from the teat boringa. Whan dloturbed a amp las were obtained, only the field aolatura aontenta wara determined for these aanplea. the dry unit weight waa determined in pound* p«r aublo foot, ena the field molature content waa oettmined aa a paroantaga of the dry aoll weight, The reeulta of thaae teats are ahown on the attaohed boring SHBAH TE3T3 Shear teat a ware performed on raaolded ae«pl«a of repreaentatlve xlte aoll. Saaplea were tested utilising a direot ahear naahine of the atraln control type. The rate of deformation waa approsiaately 0*05 inehea par minute. Each sample waa ah eared under varying normal loada to aatermina the Coulomb Shear parameter a i angle of internal friction and ooheaion* Shaar teat reaulta arm preaentea on Plate 13. UBO«ATO«Y STAMPED The maximuaj dry «enaity ana optimum molature content were determined for rapreaentatlva aamplea of aita aoll* The laboratory teat atandard uaed waa ASTH 6-1557* Method A. Naxlaam denaity ana optimum molature oontent teat reaults are preaentea belowt B-6 Geotechnioal Investigation Hay 2*1, 1988 Proposed Condominium Complex Job Ho. 7361 La Cotta, California Page 6 OptimuBBoring Depth Moiiture Maximum DryMumoer (feet) Content (I) Penalty (naf) B-1 2-5 11.5 123.0 Expenalon Imaeac Teeta« Expanoion index teata were performed on aeleeteo saaplea. Teat proeedurea were conducted In aooordanee with the Uniform Building Code, Standard Ho. 29-2. The olaealfloatlon of the expanalve noil baaed on the expanalon index, are as Indicated In Table- 29-C of the Uniform Buildlna Code. Boring Depth Expansion Potential Number (feet) Index Utpanaten B-1 2-5 73.5 Media* COMCL08IOM3 Baaed on our field Inveetigation, laboratory teating, and engineering enelyaia, it la our opinion that the aubjaot alte la auited for the proposed oonatruotlon of the eforementloned facility provided the reeommendatiDna given in this report are incorporated into the dealgn, grading^ and cenatruotlon consideratlona. 1. Site materlele eonalat of a layer of fill aoll to depth* of 8 to 11 feet* Thla aoil eonaiated of moderately expensive gray aandy olaya. Although thia material waa placed unaer B-7 Gaoteohnical Investigation Ma/ 24, 1988 Proposed Condoninlua Complex Job MO. 7361 La Coata, California supervision by • Engineer repreaentative( due to the tin* period the ait* haa been undeveloped, the near surface soil* beneath the proposed building will require denaification. 2. The aa'terlala present ere considered to have a moderate to high expanaion potential. 3. Groundwater la not expected ta ba • factor in the oevelopoant of tha aite. Hovra««r« perched water waft praaent in Borings 1, 2. end 4. 4. There are acme ooajpreaaible elaya beneath the northern aeotlon of the nite. Theae ahoula not be e ooneern ea long •a the propoaed development i« two atory oonooajiniuNS and the exiatlng grede la not ralaed more than 3 feet above the existing elevations. •tCOHHEfcDMriOIIS OTME1AL 1. Prior to the atart of any earthwork operaiiona all exiatlng potential hazarda auoh as aetive utility aerviaea and utility fiolea, ahould be located and- aeoured. Bxloting atrueturea ahould be raised or reaoved, and all debrla reooved off-aite. B-8 Qeoteohnicil Investigation May 24, 1988 Propose* Condoffllniua Conplex Job Ho. 7361 La Costa, callfornlB Page 8 2. All vegetation, saphelt, deleterious material, and loose aurfaoe aolls ahoulo be removed prior to the start of grading. All are an of proposed building pads should be undercut 3 feat from the ex lating grade, the material brought In 8 Inoh looae llfta and mechanically compacted to • minimum of 90 pereant of the laboratory standard and brought to 3 to 5 pereaat over op Maun moisture. Additionally, it *la reeoanendeb that the existing elevated pad (»«• Figure 2) be lowered to the aajaocnt pad elevation*. The Material generated fron thla gradln« should be plaoe4 over the prop««ed building P«4 ereM and brought to 3 to 5 percent over optima ooisture, and neohanieally ooapeoted to • ainiauB of 90 peroent of tha »exi«uB laboratory dry density as determined by A3TH D-1557. The lateral extent of removal and reeoapnotion shall be the building perimeter plua five feet. 3. Prior to piaoemant of reinforcing ateel sna pouring concrete, the footing excavations should be inspected by a qualified g«otechnics! engineer. it. Cxoavsted materials may be reused except for orgsnlo •aterial and trash whioh muat not be used in atruotural fill. B-9 Geotechnical Investigation Hay 24, 1988 Proposed Condonlniuo Complex Job No. 7361La Coata, California Page 9 5. All fill or backfilling afaould be plaacd in uniform lifts of approximately 8 inches leeac thickness, depending upon equipment type and approval of tht field coil technician. brought to approximately optimum moisture content* ana mechanically compacted to at laaat 90 percent of the laboratory standard, ASTM D-1557. 6. A flhatpa-foot typa oaopaQtor la noraally affeotlv* on olayey •at trial. If granular material is ua«a for the atructural fill* a vibratory roller la noroally aora affaetiv.e and 10 recommended. 7. A qualified aolli teohnloian under the supervision of a geotaannloal engineer aitould be preaent for all fill or beokfilling placement operattona. The aoila taehnleian ahould evaluate all materials to be plao«d, sna ahould perform in^plaoe density taata mt appropriate intervals to evaluate the compaction effort relative to 90 percent of the maximum dry density aa determined by ASTN 0-1557. 8. Hew filie raising the existing grade at the elta ahould not exceed 3 feet in height. FOUiPATlOl M8ICT A«D COM3THUCTIOM 1. All footings ahould be reinforced aa per a regiatereo structural engineer 'a raconaendatlons* B-10 Gaotechnleal Investiiation Hay 34, Proposed CondOBlnlua Conplex Job No. 7361 La Coata, California Page ID 2i All foot'inga for individual atruoturea ahould Be founded in similar natural Mil or atruotural fill to Minimize poaaible differential a eminent. 3. Katorlor footlnga ahoula be founded a ajinloum depth of 18 inohoa below the lowest adjacent grad«. Interior Foottnia •ay M founded at a depth of 12 inehea below the loweat adjaoent (round aurfaoe. All footing* ahould have a •Ininum of oti* Mo. 4 relaforetni bar placed at the top eno bottoe of the footing, or aa apeoifiea by the atruatural entineer. rooting width ehoula be a ainlnuM of 15 inohea. 4. Conoreta alaea ahould be underlain by four inohea of oleen aand or aruvhed rook. In addition, a vapor barrier oonalatlnf of • anniawa of alx mil polyvinyl chloride •embranc. with all lapa aeeled, ahould be provided for all interior living area alaba and areaa that aay be advaraely affeeted by aolature. One Inoh of sand ahould be plaeed over the MBbrane to aid in the uniform during of the eon«rete. 5. Concrete alaba ahould be relaforeed with at Zea»t Ho. 3 reinforoing bar* 18 inahea 0n eenter eaoh way. All slab reinforcement ahould be supported to enaure '.proper ponitloning in the alab during plaoeoent of oonarete. 6. Concrete alaba ahould be aoored, or fitted with ospanaion Joints at appropriate intervelo. B-11 Ceo technical Investigation Hay 21, 1988 Proposed CondoalnluB Complex Job Ho. 7361 La Costa, California Paga 12 Lateral reaiatanoe aey be developed using p waive Boil pressure sp proxies ted by an equivalent fluid unit weight of 150 pounds per oil bia foot. In addition, frldtional resistance nay b« eetlnsted between soil tna oonorete using s opefficient of f nation of *0.30. Drainage behind ell walla should be sufficient to ensure that no free Moisture aeouaulatea behind the wall. A 12 Inch width of granular backfill in conjunction with a avata» of perforated drain pipe should be detained and oonatructed Tor thia purpoaa« MAMS Positive drainage away fro« the proposed structure should be •alntained within a ainlaua of ten feet of the building, Stepa should be taken to avoid ponding near the footings. loof~guttera and dovn-apouta ahoulo be used to svoid ponding of water near the foundation line. Pl*eeawnt of planter* and extensive landaoaping le not roooanended within tan faet of the footiaga. Drainage requiraaenta ahould be ispleswnted in aooordenee with Unified Building Cooaa and the loeal regulations. The final foundation and grading plana ahould be reviewed by thia office to •iniajise any •iaundaratandlnga between the plans and reeoamendatlona presented herein. In addition, foundation excavations ana earthuork perforaeo on-site ahould be evaluated B-12 * Geotechnical Inrestlgatlon Hay 24, 1988 „ Propoied Condoainiua Complex Job No. 7361La Coata, California Pige 13 m "* Dy » qualifivd tngln««rlng a«ologl«t or Geotcohnteal Enflitor. If •m oondltlons »re found to vary subitantlslly from those «tBt*d *" herein, appropriate roaoatMndatlana ahould b« raqueataa. B-13 Geetechnical Investigation Hay 24, 1988 Proposed Conflonlniun Complex job Mo. 7361 La Coata, California Page 14 IIVESTIOATIOII LIMITATIOHS The naterlela encountered on the project aita and utilized in our laboratory Investigation ar« bell«v«d repraaentativea of the total area; however, coll and bedrock eater!ala very in oharaeteriatloa between exoavatlona and natural outcrop*. This report in no way oonatltutra oertlfioation of th« exiitirtg fill or aubaurfacc aolla. Slnoe our Invaatltation la baaed on the aito oateriala obaerved, aaleativc laboratory taatlnf and engineering analyaea, the oonoluaiona and raooauaandationa ar« profeaolonal opinion. Thaae opinion have ba«n derived in aooordaaoa nith current atandarda of practice and no warranty la «rpr«aaed nor iapliea. It ia reooauaandea that Taatiac En|ln«ara-San filega, be retained to provide continuous aoll enfinearlog aervloea during the earthwork operationa. Thla la to obaerve ooaplianoe with the deaign ooneepta, apealfloatlone or reeommannatlona and td allow daaign change* In the event that aubaurfaoe eondltlonn differ frea thoae anticipated prior to atart of eonatrudtlon. Inapectlon aervioea allow the teating or small pereantagaa of the fill placed at the site. Contractual arrangements with the grading contractor ahould contain the provialon that he la reapanaibla for excavating, placing, and eoapactlng the fill in aocoraance with the project apecifieatlona. Inapectlon by tha B-14 Geotaohnlcal Invalidation May 24, 1988 Proposed Condooinlun Complex Job Ho, 7361 La Costa, Cillfornla Page IS gootechniesl engineer during grading should not relieve the grading contractor of his prlMry responsibility to perform ill work in accordance with the specifications. This off lot should be advised of any changes In tho project scope of tho proposed Site grading so that it may bo aotarmined if the roaoaiaand«tion« contained herein ere appropriate. This ahoulo be verified in writing or aodificd by e written atfdendua. Tne findings of this report are valid as of thia date. Changes in the oondltiono of • property oan, however, ooour with the paoaage of time, whether thoy be due to natural prooo»aea of the work of tt«n of Its or adjaoent proper-ties. In addition, changes in the •tate>of«the-art and/or Government Codes may oeour. Due to such changes, the findings of this report may be invalidated wholly or in part by changes beyond our control. It is the) responsibility of the owners, or their repreaentative to enaure that tha information and recommendations contained herein are brought to the attention or the engineer and architect for the project and incorporated Into the project's plans and •pacifications. It it further the responsibility to take the necessary meaaures to ensure that the oontrmotor and hi* •ubcontracta carry out aueti recommendations during construction. B-15 Testing Engineers-San Diego BORING LOG Project; Hampiir si - .4 •e •a -MZ •H ,. •18 .20 •22 24 .20 28 | SO CH La &»•«• Coitdo Flute. 4-H-fA f)|f . JSUULB"?? Hule Ol'fwlff • s iufhui- WtlflM H Ml; 140,ibB/?Pll.. Gruuntf Wfltir: _ HELD BUCWTION Clay tend! clay approximately J3X. i«nd ««i *mdiia to eoatMi •liglitly anise, loot* olivft gray, idth grtval up to 1/4 inch id length . S. 0-1 1.0' OUyeontwfc incr««a««, ehunkn et cluy MfemM pr«a«oc. • 11.0* Clayi^ (Ibcural) ULgbC ollvw grey •lightly Mmdly approxiiMkaly 10X, cl*y •pyrralM««ly 90X» avlt. voivt. At 12-13.0' davfc arganle lay«r» present. . At 15*17.0* MINI Mutant ineraaaaa, !•»(• aaVwigulnr gravel 2.5 by 2.5 incblq •aaplnr 17-20* Clay, !••• land eoncvnc Clay becoWM black in ealor •ppxaxi»aecly 152 fine Co Mdiiw ««nd, miit, nit. At 23.0* •otaeure eootant lncc««a«a. At 28.0' color cnangM to grey. t § 21 14 19 19 11 Hfl- _,- » ElfvatliM. . LojgM By: JSL_ M I DH Bulk Oil•ulk OR Bulk DR DR bi* 121 117 90 • 104 96.0 if 11.2 n 16.2 14. B 26.1 2 8i . • I PLATE. B-16 lesnng Lngjneer$-Son Diego I * BORING LOG Prtjiet: I* Co«U Cendfl fafe, 4-28-88 Typt of rag:J£!ZiLi2Z__ Holt DlnmtUr, «JJ2S* HBirirocr Weigh' ft Pm-.J*P--iM/ao* ._ Groond Wni» :^ iif. .30 1-32 34 •M f-ae Mo 42 48 ao 52 94 SM SC AC 31.0*lmco«M very wit«e. 34-40.0*iMuiy Silt: SccuraCMl «ly UZ M41w iwul» 10X el«y.69t •lie, mffe, any in color. 40-61.0* ftwdy •edlluri »M«4, 952 Aravaxiutrty »I »M«4, 952 cLiy» vary •oiat.Mdiua «n4 gr«y In toloc. At 4o.O* mnd coatM At 40.0' ctey becowu wdtiiM «iff to •tiff. J«rk organic l«y«r« inc«minBi«d. At 56.0* chunk* of clay»ton« pr««mc.•oict. 4*0»«. 20 34 54 M OK m DK toi 107 101 lot JD9 24.5 22,5 24. « 12.7 J9.3 26,6 B-17 res//ng Engineers-Son 0/ego BORING LOG Prfljtct>La Ca«t* Cmdo fViU. 4-28-81 Typ. *f Hla-WattE 1-37 _ ||fli, DJH^,ta,, 8 inch.. Boring Kin. f. FMwflflAn* Hffinmw VMnM ft Pull 440 lfc«/W C,m..rf W*IM. 1 MMrf R«. SEW f 58 eo ••a 94 •99 • •* > H» • 99 1 * ^™" FIELD DCSCMpTiOM i • m 61-44.0' Said1 Iwu, wMltUB to caarM. *Mtftat«4> iafc«nataal*d «dfek t»4y d«yt . approjdMCaly UX aadiiai aanl, approidMta: 7« clay, Mi«t. nadiiM atif£» ftny in tcolor. 1, • TOTAL DEPTH 63,0* 60-46. 0' Xntmingltd land lm« Mdlm ta cotr««, with Cl«y Wnd !•»• Mturatcd- clay ia aolae. 1 33 r . 25 | OR DB h S" 110 101 • ifII 20.4 24.8 S1 • * J FLUTE. B-18 Testing Engineers-Son Diego BORING LOG Project: Tjpo Of Hoinintr i • a 4 6 i ( 12 •14 10 •20 •22 •24 •28 •28 | SM OH SC u co.ta cattda r^tm. 4-u-ae B|q. HOBZLS i-37 Hfl(| oiani.jg,. 8 loehaBoring • *.b,M A Ml. 148 l»a./30" fl^rf *«,.,. rieui oeicmpTKM 0-1.5* landy tllti avatoxlaatalf 302 •adiuai aan4. 552 "illt, aliajitly ooiat. 100M, yallowish tan in COlat Clay eratant inoraaaca with doth, mftattura iacTwasca with tfavch. - 1,5-13.0* Clayj^ approxiBataly 102 (in* aaa4. 902 clay wLth ngaalei pcaacnt.•olat, Bwllun aeiff , black or dart gray'*ty colav. 13-19.0' tmnAy Clay! Band content incraaaaa Co •ppmiMCaly 252. sut cantmfc inet«a»aa with depth. 19* aaady »ilt Clay; faceantagaa of •and. allt. and clay 'appear almat 21 .5 TarebaA iMtw, tottoai of aawalar aacuratadt alight hydraatatls praaaura•rritfant At 25* oaapla aaniratM auovs/'r17 20 23 24 23 10 No- 2 Elovotk . Lofloc J DR Bulk mi DR W DR DR rfflr'™ !T^^ h i 100 106.0 112 113 109 101 it ,,a 20.3 11.9 20.7 19.6 25.6 § • - 1 B-19 Testing Engineers-San Diego £ 4 BORING LOG P^f UCMC»Ca«4o B,.,.. 4-M-M lb.ta.lta, J RmJIOBTI.e 1-57 M«h Item,.!.*. I incb«« Hflmifi* W.lnM A Bull. 140 lbo/30" e«,11M| «„!.. I 30 32 •34 ,M •40 • 42 .44 1 • FIELD DEttftiniOM Batunted Mndy eUycy ailt, IODM, •ole«4 dark bran* and fray. • . 35* Sandy clay ailt aatu«*t«d •aturacad alley aand In aaaplar ta 41.0' •1.0* Silty and, molac, Mdltta danaa aach Vrewn in color TOTAL nrn 41.3' ElMftfh in. 1 iimuil Rw. 8EU BLOWS/FT15 Z& 27 Ul OX Da DK • !E S" 101 100 105 gfSi 25.2 « 23.7 • if 8 • PUTE. B-20 resting E/ig/neers-San. Diego BORING LOG Pmjicl:Cnnila Big.MDBlU. *fIKU)IPTION lI § •10 18 18 0 2 SC sc OH sc 0-2* lAMft CtATiopproKl^C»ly 301 •ediuai ti KM Mod, Appvoxiaatoly 70S cl«y, »wli aaditav-fttlf f, tan in evloz. ,-8.0* fMOHKlT!appro*t»at«ly 20Z M<Slun '02 ciJ,c> Boiofci g^^^mg ^ttHB( and kon in e«lar. 1-11.0* 202 31 •pptoxiwtoly BOX clay. Mice, acift, and gray la color. 47 69 it iff.11-13 .fl' WLTT OATtatm to wile. d«slt gray in colqr. 13-16.0* JAMM CUY;appto3ci»«t.ly 20X •MX dlQfa •aWASt •tiff, gray in color. Sand contant iim«*a4*.. with d*pcb. 16-ie.O' Smd Uno;appttmiMt«ly 202 *ilt.' a>p»tOHilHtaly got mmAltim to coorm Mnd. in eolo*. 59 18-21.5* B1MPT CTJOftapprmUattt^ily 30t apprmlaweo&y 70S clvyi ««iat acift to atiff, gray in colav. . TOTAL DEPTH 21.5* OH DK DK Dt M 14.3 101 16.5 17.6 114 15.5 104 21.2 PLATE. B-21 Testing Engineers-Son Diego BORING LOG PM]M>». L« Cuoeo Coiuio n-u. S-Z-M , ft-.f^j M«. 4 TflU «f ftlg.linmTT * •-*! U«l^ nfmM^,. ff l-rl— , ~ rhiMllmr. , , , Hommir Wotyil ft Fall; u° i»«T . *»".. Ground «•!«: JP^l*-. 1 oggid By: JflL.. i •2 .4 •ft •0 •10 ta .14 •lotIV IB •20 •22 •24 •20 | sc OH • * • * ncu otxwfwoN 0*11.0* IAWW CUti (ItU). •porowbMeoly UX cloy, oolot. oclff . COB ta color. At 4.0' bocOMI |voy in «ol0lt. . OnoJiB ol elayicono i* eh* boetcm of the w«pl«r M«y hiv« «wuor»M4 Bb* blow couol m U-13.5' BABOl CtAti (Nattttal). oftirndMCi YT 71KC B^fl'Tiii f *ini1 1 f[it|||"Tn'im'[^l'y 7ffi( cY^y •0i*c, skiff, iroy to olivo-griy la color.* 13.3-17.0' S«4 Unot •potoafJMtoay J3Z•lie, oop«oxi«oe«ly *3X MMUMI to CO«XM 0004, *Mty rtoiot, 4oBM| gc**/ *" color. 17-31.01 «UT OJlTi HMim ttlfl to oclff •olot, fJ«ck ft«y in color. , 27-JO.' rorehod w»t«r. 5 33 32 43 - 7) 7ft 34 . m OK OK lit OH OH BeI£ 99 106 114 , IIS i«e 9* I*ii 20.4 18.2 17 ' 13.7 11.7 23.3 2 B * PUTE. B-22 Testing Engineers-Son Diego * I 4 BORING LOG p^,,. U C..f CmuJo ^|B. S-2-ii B-i^, II-. *BOTNflFrl•30 M ••4 • • J sc AM A A A KfeM^^dAMBKMFIELD DCSOttFilOM 31-31.3' SAOTJ_ttttiwptoxla»t«ly Z3X •flllf "^^ •MA^^^^BttVttttilBAt AXV 79^ £ IM¥ ttBlK •(if ft can In «alor. WtAl BBFtH 31.5* • « 4 I 1 M/SMH22 j DX i" 9ft s ifii 27.4 88 PLATE. B-23 Testing Engineers-San Diego SYMBOLS AND TERMS USED ON BORING LOGS •%a«r »*0 SAMPLER TYPES » to J«Mlf «MfU H wW SS TERMS OCSCfllBlNQ COH3GTEHCY OR CONDITION QMMK (MHO UU l«wtoi )*«MMMMi«i Nt tM iMh totMa HI <liM *w«li pucmmvt mm «M tt O te 4 4 M10 M> 1*90 90 H90 tin tMfHr.jMjk wiiiif not. «M tsi dHtf un Until tweMti (II IwiMlc «M Vtri Mil Ml nim SMI Vfcr| tltff WIBIIMMKD 1NCM VmlNOTNwrt/nrt IH« IMA O.IS aa i« USD OM te 1.00 1JM to IAD toj 4.00 liMMltaMUt TERMS CHARACTEmziNQ SOIL STRUCTURE r mu4 Hm KM «m« «r H», iwM«f MM i ftfl ftf •A* M UMTOO SOIL CLunnarMW sort* « *»<»•¥» HUWMI B-24 H LA COSTA AVENUE •CALK 1 tNCH - «0 FEET Testing Engineers-San Diego BORING LOCATIONS TM1 I *'•*-»«.••I FIOIffiEa B-25 APPENDIX C BORING LOGS GeoSoils, Inc. PROJECT: SCI ENTERPRISES La Costa Green § f & 5- m- 15- - 20-5 25- Sample • I »-$ i| 1 1 w, n 1 WA ! 36 22 16 28 13 12 •g §1 CL SC CL Dry Unit Wt.(pcf)108.6 107.0 93.0 114.1 91.9 101.9 Moisture (%)12.8 13.9 24.8 14.5 28.5 22.3 g w 64.9 67.5 84.4 85.6 94.4 95.0 BORING LOG W.O. 3401 -A-SC BORING B-1 SHEET 1 OF 1 DATE EXCAVATED 9-12-02 SAMPLE METHOD: MODIFIED CA SAMPLER 1 40LB HAMMER @30" DROP i Y// Standard Penetration Test , . -*- GroundwaterUndisturbed. Ring Sample Description of Material I ^ I ^ I ARTIFICIAL FILL: @ 0' SANDY CLAY, light brown, damp, soft. @ 2V£' SANDY CLAY, light brown to yellow brown, damp to moist, very stiff. @ 5' SANDY CLAY, light brown to yellow brown, moist, very stiff. @ Tfi CLAY, light brown to gray to yellow brown to orange, moist, stiff. DELMAR FORMATION: @ 10' CLAYEY SANDSTONE, yellow brown, moist to wet, medium dense; massive. @ 15' CLAYSTONE, dark gray to black, wet, stiff, sub horizontal bedding. @ 20' SANDY CLAYSTONE, gray to yellow brown to orange, x saturated, stiff; groundwater encountered. /- Total Depth = 21' Groundwater Encountered @ 20' No Caving Encountered Backfilled 9-12-02 LaCostaGreen GeoSoils, IPC. pM7E w GeoSoils, Inc. PROJECT: SCI ENTERPRISES La Costa Green Depth (tt.)- 10- 15- 20- 25- Sample J£ m »!•ojS §1 H w/, w/, n CD 35 33 32 69 s!w 5.3 CO SC CL SC Dry Unit Wt.(pcf)104.7 106.7 110.9 116.3 Moisture (%)12.4 15.1 13.3 12.4 Saturation (%)56.5 72.7 71.1 77.7 BORING LOG IV. O. 3401-A-SC BORING B-2 SHEET 1 OF 1 DATE EXCAVATED 9-12-02 SAMPLE METHOD: MODIFIED CA SAMPLER 140LB HAMMER @30" DROP i m Standard Penetration Test , . -^- Groundwater \ Undisturbed. Ring Sample Description of Material I m 1 ARTIFICIAL FILL: @ 0' CLAYEY SAND, light brown, dry, loose. @ 1' CLAYEY SAND, light brown to yellow brown to orange, dry to damp, medium dense. @ 3' SANDY CLAY, light brown to yellow brown to orange, moist, very stiff. DEL MAR FORMATION: @ 5' CLAYEY SANDSTONE, light brown to yellow brown to orange, damp, medium dense. @ T CLAYEY SANDSTONE, yellow brown to gray to orange to black, x moist, dense; massive. /- Total Depth = 8' No Groundwater/Caving Encountered Backfilled 9-12-02 LaCostaGreen GeoSoilS, JHC. ^ „ BORING LOG GeoSoils, Inc. W.O. 3401 -A-SC PROJECT: SCI ENTERPRISES BORING B-3 SHEET 1 OF 1 La Costa Green DATE EXCAVATED 9-12-02 e f _ 5- - _ - 10- - 15- 20- 25- Sample i•5.2 53 ^tffr* ^'///I . I 30 21 35 w t3 CO SC CL SC CL jj I 107.5 102.3 109.7 •? ¥ 1 15.2 14.7 16.8 oS § 3 CO 74.6 62.9 82.6 &4MP/.E METHOD: MODIFIED CA SAMPLER 140LB HAMMER @30" DROP Standard Penetration Test AZ. Gmnntiwator Undisturbed, Ring Sample Description of Material //?, '% %./// //. fa yfy><xxx> ARTIFICIAL FILL: @ 0' CLAYEY SAND, light brawn, dry to damp, loose. @ 2VJ SANDY CLAY, yellow brown to gray, moist, very stiff. DEL MAR FORMATION: @ 5' CLAYEY SANDSTONE, yellow brown, moist, medium dense; massive. @ 7Vi' SANDY CLAYSTONE, yellow brown to gray, moist to wet, very -v stiff; massive. /- Total Depth = 81/*1 No Groundwater/Caving Encountered Backfilled 9-12-02 , „ . ^ GeoSoils, Inc. ,. r.La Costa Green ' PLATE c"3 GeoSoils, Inc. PROJECT: SCI ENTERPRISES La Costa Green f § - 5_ - 15- 20- 25- Sample ^"3.2si M i M M m CO 34 17 36 18 35 col §1 SC CL CL Dry Unit Wt.(pcf)111.1 108.3 112.7 105.0 109.6 Moisture (%)9.4 11.5 13.3 18.6 15.0 Saturation (%)50.9 57.8 75.4 85.4 78.2 BORING LOG W.O. 3401-A-SC BORING B-4 SHEET 1 OF 1 DATE EXCAVATED 9-12-02 SAMPLE METHOD: MODIFIED CA SAMPLER 1 40LB HAMMER @30" DROP m % Standard Penetration Test AZ. Groundwater Undisturbed, Ring Sample Description of Material | !\ ARTIFICIAL FILL: @ 0' CLAYEY SAND, light brown to orange, dry, loose. @ 1' CLAYEY SAND, light brown to orange, dry to damp, medium dense; scattered pebbles. @ 3' CLAYEY SAND, light brown to yellow brown to gray, moist, loose; scattered pebbles. @ 5' SANDY CLAY, light brown to gray to yellow brown, moist, very stiff. DEL MAR FORMATION: @ 7 SANDY CLAYSTONE, yellow brown to gray, moist to wet, stiff. @ 10' SANDY CLAYSTONE, yellow brown to gray, moist, very stiff. Total Depth = 11' No Groundwater/Caving Encountered Backfilled 9-1 2-02 LaCostaGreen GeoSoils, |flC. ^ „ GeoSoils, Inc. PROJECT: SCI ENTERPRISES La Costa Green § 5- 10- 15- 20- 25- Sample .*1 Undis-turbed^m m 03 E HI0(0 SC/CL CL CL/SC CL Dry Unit Wt.(pcf)101.3 Moisture (%)10.7 10.1 1 1 CO 42.4 BORING LOG IV. O. 3401 -A-SC BORING B-5 SHEET 1 OF 1 DATE EXCAVATED 9-12-02 SAMPLE METHOD: HAND AUGER/ RING SAMPLER Standard Penetration Test -VL Gmundwafar M.Undisturbed, Ring Sample Description of Material .J M ••J Y/// ARTIFICIAL FILL: -\ @ O1 CLAYEY SAND/SANDY CLAY, gray, dry, very loose/very soft. /- @ 1' SANDY CLAY, gray, dry to damp, very soft. @ 2' SANDY CLAY, gray to yellow brown, dry to damp, medium stiff. @ 3' SANDY CLAY/CLAYEY SAND, yellow brown to gray, damp, •x medium stiff/medium dense. /- @ 4' SANDY CLAY, dark brown to orange, moist, stiff. ^ @ 5' SANDY CLAY, dark brown to yellow brown to orange, moist, stiff. ^ Total Depth = S1/*1 No Groundwater/Caving Encountered Backfilled 9-12-02 LaCostaGreen GeoSoilS, IRC. pM7F „ APPENDIX D LABORATORY DATA 3,000 2.500 2,000 a i $ 1.500 (0 (0 1,000 500 0 ^ , ^ k^ ^ < ^^\ i I 0 500 1,000 1.500 2.000 2,500 3.000 NORMAL PRESSURE, psf Sample Depth/El. • B-1 0.0 • B-1 0.0 Primary/Residual Shear Sample Type % MC% c <|> Primary Shear Remolded 110.8 13.5 1444 26 Residual Shear Remolded 110.8 1469 24 Note: Sample Innundated prior to testing GeoSoils, Inc. jam 40* « 5741 Palmer Way (g&tSJlSc. Carlsbad, CA 92008 ^WFiiP* Telephone: (760)438-315! Fax: (760)931-0915 DIRECT SHEAR TEST Project: SCI. ENT. 5 Number: 3401-A-SC Date: September 2002 Figure D-1 as z « • i 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.011 ^ ------ ~^1 { ^ ^ \ ^ < "~< - ^^ ^\ ^\, \ \ ^ DO 1,000 STRESS, psf Sample Depth/El. Visual Classification B-3 2.5 Sandy Clay GeoSoils, Inc. jrttmr 5741 Palmer Way ARlSc. Carlsbad, CA 92008 «F* Telephone: (760)438-3155 Fax: (760)931-0915 \1 \ ^-~^ \\ ~- \ ^~^ ^1 » 10,000 % Initial 107.5 MC Initial 15.2 MC Final 18.5 H20 1000 CONSOLIDATION TEST Project: SCI. ENT. Number: 3401-A-SC Date: September 2002 Figure D-2 ^ z •€ • %iSi3S 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 1 •\ ^N•x V N, N, \ \ X \ X,, \1 X \ N \ \, i \ \ ^ 30 1,000 STRESS, psf Sample Depth/El. Visual Classification B-1 7.5 Clay GeoSoils, Inc. 4Pt<» 5741 Palmer Way DpKlie. Carlsbad, CA 92008 W* Telephone: (760)438-3155 Fax: (760)931-0915 \ \ ^\ \ "^ \\ — - — . \ \ • — . \ •~i1 10,000 Yd Initial 93.0 MC Initial 24.8 MC Final 27.8 H20 1000 CONSOLIDATION TEST Project: SCI. ENT. Number: 3401 -A-SC Date: September 2002 Figure D-3 STRAIN, %< • 1 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 1 • — .< ( ^ •\ — \. -^ ^^ < ~« x ^^^ \, \\ >\ 30 1,000 STRESS, psf Sample Depth/El. Visual Classification B-4 5.0 Sandy Clay GeoSoils, Inc. ^M • 5741 Palmer Way DfKlfe. Carlsbad, CA 92008 <«** Telephone: (760)438-3155 Fax: (760)931-0915 \ N "~-~^ i \ - — ^ \ \ • — . \ - — . ^ ) 10.000 % Initial 112.7 MC Initial 13.3 MC Final 16.9 H20 1000 CONSOLIDATION TEST Project: SCI. ENT. Number: 3401 -A-SC Date: September 2002 Figure D-4 L \ a< 0 • 60 50 5 40 ' I 20 10 0I / CL-ML 3 Sample B-1 / S / / CL ., H / ML CH / / MH / / / / / ' / / 20 40 60 80 100 LIQUID LIMIT Depth/El. 0.0 LL 48 PL 18 PI 30 Fines Classification GeoSoils, Inc. ^3UE|& Carlsbad, CA 92008 '•WlflFA Telephone: (760)438-3155 Fax: (760)931-0915 ATTERBERG LIMITS' RESULTS Project: SCI. ENT. Number: 3401 -A-SC Date: September 2002 Figure D-5 M. J. Schiff & Associates, Inc. Consulting Corrosion Engineers - Since 1959 1308 Monte Vista Avenue, Suite 6 Upland, CA 91786-8224 Phone: 909/931-1360 Table 1 - Laboratory Tests on Soil Samples SciEnt Your #3401-A-SC, MJS&A K02-0921LAB 20-Sep-02 Sample ID Resistivity as-received saturated PH Electrical Conductivity Units ohm-en ohm-en mS/cm Chemical Analyses Cations calcium magnesium sodium Anions carbonate bicarbonate chloride sulfate Other Tests ammonium nitrate sulfide Redox Ca2+ Mg2+ Nal+ CO32' HC03 U Cl1' so4 2- NH41+ NO3'' S2' mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg qual mv B-l @0-5' 4,400 435 5.9 1.13 629 153 271 ND 52 195 2,375 na na na na Electrical conductivity in millisiemens/cm and chemical analysis were made on a 1:5 soil-to-water extract, mg/kg = milligrams per kilogram (parts per million) of dry soil. Redox = oxidation-reduction potential in millivolts ND = not detected na = not analyzed Page 1 of 1 Figure D-6 APPENDIX E GENERAL EARTHWORK AND GRADING GUIDELINES GENERAL EARTHWORK AND GRADING GUIDELINES General These guidelines present general procedures and requirements for earthwork and grading as shown on the approved grading plans, including preparation of areas to filled, placement of fill, installation of subdrains and excavations. The recommendations contained in the geotechnical report are part of the earthwork and grading guidelines and would supersede the provisions contained hereafter in the case of conflict. Evaluations performed by the consultant during the course of grading may result in new recommendations which could supersede these guidelines or the recommendations contained in the geotechnical report. The contractor is responsible for the satisfactory completion of all earthwork in accordance with provisions of the project plans and specifications. The project soil engineer and engineering geologist (geotechnical consultant) or their representatives should provide observation and testing services, and geotechnical consultation during the duration of the project. EARTHWORK OBSERVATIONS AND TESTING Geotechnical Consultant Prior to the commencement of grading, a qualified geotechnical consultant (soil engineer and engineering geologist) should be employed for the purpose of observing earthwork procedures and testing the fills for conformance with the recommendations of the geotechnical report, the approved grading plans, and applicable grading codes and ordinances. The geotechnical consultant should provide testing and observation so that determination may be made that the work is being accomplished as specified. It is the responsibility of the contractor to assist the consultants and keep them apprised of anticipated work schedules and changes, so that they may schedule their personnel accordingly. All clean-outs, prepared ground to receive fill, key excavations, and subdrains should be observed and documented by the project engineering geologist and/or soil engineer prior to placing and fill. It is the contractors's responsibility to notify the engineering geologist and soil engineer when such areas are ready for observation. Laboratory and Field Tests Maximum dry density tests to determine the degree of compaction should be performed in accordance with American Standard Testing Materials test method ASTM designation D- 1557-78. Random field compaction tests should be performed in accordance with test method ASTM designation D-1556-82, D-2937 or D-2922 and D-3017, at intervals of approximately 2 feet of fill height or every 100 cubic yards of fill placed. These criteria would vary depending on the soil conditions and the size of the project. The location and frequency of testing would be at the discretion of the geotechnical consultant. GeoSoils, Inc. Contractor's Responsibility All clearing, site preparation, and earthwork performed on the project should be conducted by the contractor, with observation by geotechnical consultants and staged approval by the governing agencies, as applicable. It is the contractor's responsibility to prepare the ground surface to receive the fill, to the satisfaction of the soil engineer, and to place, spread, moisture condition, mix and compact the fill in accordance with the recommendations of the soil engineer. The contractor should also remove all major non-earth material considered unsatisfactory by the soil engineer. It is the sole responsibility of the contractor to provide adequate equipment and methods to accomplish the earthwork in accordance with applicable grading guidelines, codes or agency ordinances, and approved grading plans. Sufficient watering apparatus and compaction equipment should be provided by the contractor with due consideration for the fill material, rate of placement, and climatic conditions. If, in the opinion of the geotechnical consultant, unsatisfactory conditions such as questionable weather, excessive oversized rock, or deleterious material, insufficient support equipment, etc., are resulting in a quality of work that is not acceptable, the consultant will inform the contractor, and the contractor is expected to rectify the conditions, and if necessary, stop work until conditions are satisfactory. During construction, the contractor shall properly grade all surfaces to maintain good drainage and prevent ponding of water. The contractor shall take remedial measures to control surface water and to prevent erosion of graded areas until such time as permanent drainage and erosion control measures have been installed. SITE PREPARATION All major vegetation, including brush, trees, thick grasses, organic debris, and other deleterious material should be removed and disposed of off-site. These removals must be concluded prior to placing fill. Existing fill, soil, alluvium, colluvium, or rock materials determined by the soil engineer or engineering geologist as being unsuitable in-place should be removed prior to fill placement. Depending upon the soil conditions, these materials may be reused as compacted fills. Any materials incorporated as part of the compacted fills should be approved by the soil engineer. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells, pipelines, or other structures not located prior to grading are to be removed or treated in a manner recommended by the soil engineer. Soft, dry, spongy, highly fractured, or otherwise unsuitable ground extending to such a depth that surface processing cannot adequately improve the condition should be overexcavated down to firm ground and approved by the soil engineer before compaction and filling operations continue. Overexcavated and processed soils which have been properly mixed and moisture conditioned should be re-compacted to the minimum relative compaction as specified in these guidelines. SCI Enterprises, LLC Appendix E File:e:\wp7\3400\3401a.pge Page 2 GeoSoils, Inc. Existing ground which is determined to be satisfactory for support of the fills should be scarified to a minimum depth of 6 inches or as directed by the soil engineer. After the scarified ground is brought to optimum moisture content or greater and mixed, the materials should be compacted as specified herein. If the scarified zone is grater that 6 inches in depth, it may be necessary to remove the excess and place the material in lifts restricted to about 6 inches in compacted thickness. Existing ground which is not satisfactory to support compacted fill should be overexcavated as required in the geotechnical report or by the on-site soils engineer and/or engineering geologist. Scarification, disc harrowing, or other acceptable form of mixing should continue until the soils are broken down and free of large lumps or clods, until the working surface is reasonably uniform and free from ruts, hollow, hummocks, or other uneven features which would inhibit compaction as described previously. Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical), the ground should be stepped or benched. The lowest bench, which will act as a key, should be a minimum of 15 feet wide and should be at least 2 feet deep into firm material, and approved by the soil engineer and/or engineering geologist. In fill over cut slope conditions, the recommended minimum width of the lowest bench or key is also 15 feet with the key founded on firm material, as designated by the Geotechnical Consultant. As a general rule, unless specifically recommended otherwise by the Soil Engineer, the minimum width of fill keys should be approximately equal to Vz the height of the slope. Standard benching is generally 4 feet (minimum) vertically, exposing firm, acceptable material. Benching may be used to remove unsuitable materials, although it is understood that the vertical height of the bench may exceed 4 feet. Pre-stripping may be considered for unsuitable materials in excess of 4 feet in thickness. All areas to receive fill, including processed areas, removal areas, and the toe of fill benches should be observed and approved by the soil engineer and/or engineering geologist prior to placement of fill. Fills may then be properly placed and compacted until design grades (elevations) are attained. COMPACTED FILLS Any earth materials imported or excavated on the property may be utilized in the fill provided that each material has been determined to be suitable by the soil engineer. These materials should be free of roots, tree branches, other organic matter or other deleterious materials. All unsuitable materials should be removed from the fill as directed by the soil engineer. Soils of poor gradation, undesirable expansion potential, or substandard strength characteristics may be designated by the consultant as unsuitable and may require blending with other soils to serve as a satisfactory fill material. Fill materials derived from benching operations should be dispersed throughout the fill area and blended with other bedrock derived material. Benching operations should not result SCI Enterprises, LLC Appendix E File:e:\wp7\3400\3401a.pge Page 3 GeoSoils, Inc. in the benched material being placed only within a single equipment width away from the fill/bedrock contact. Oversized materials defined as rock or other irreducible materials with a maximum dimension greater than 12 inches should not be buried or placed in fills unless the location of materials and disposal methods are specifically approved by the soil engineer. Oversized material should be taken off-site or placed in accordance with recommendations of the soil engineer in areas designated as suitable for rock disposal. Oversized material should not be placed within 10 feet vertically of finish grade (elevation) or within 20 feet horizontally of slope faces. To facilitate future trenching, rock should not be placed within the range of foundation excavations, future utilities, or underground construction unless specifically approved by the soil engineer and/or the developers representative. If import material is required for grading, representative samples of the materials to be utilized as compacted fill should be analyzed in the laboratory by the soil engineer to determine its physical properties. If any material other than that previously tested is encountered during grading, an appropriate analysis of this material should be conducted by the soil engineer as soon as possible. Approved fill material should be placed in areas prepared to receive fill in near horizontal layers that when compacted should not exceed 6 inches in thickness. The soil engineer may approve thick lifts if testing indicates the grading procedures are such that adequate compaction is being achieved with lifts of greater thickness. Each layer should be spread evenly and blended to attain uniformity of material and moisture suitable for compaction. Fill layers at a moisture content less than optimum should be watered and mixed, and wet fill layers should be aerated by scarification or should be blended with drier material. Moisture condition, blending, and mixing of the fill layer should continue until the fill materials have a uniform moisture content at or above optimum moisture. After each layer has been evenly spread, moisture conditioned and mixed, it should be uniformly compacted to a minimum of 90 percent of maximum density as determined by ASTM test designation, D-1557-78, or as otherwise recommended by the soil engineer. Compaction equipment should be adequately sized and should be specifically designed for soil compaction or of proven reliability to efficiently achieve the specified degree of compaction. SCI Enterprises, LLC Appendix E File:e:\wp7\3400\3401a.pge Page 4 GeoSoils, Inc. Where tests indicate that the density of any layer of fill, or portion thereof, is below the required relative compaction, or improper moisture is in evidence, the particular layer or portion shall be re-worked until the required density and/or moisture content has been attained. No additional fill shall be placed in an area until the last placed lift of fill has been tested and found to meet the density and moisture requirements, and is approved by the soil engineer. Compaction of slopes should be accomplished by over-building a minimum of 3 feet horizontally, and subsequently trimming back to the design slope configuration. Testing shall be performed as the fill is elevated to evaluate compaction as the fill core is being developed. Special efforts may be necessary to attain the specified compaction in the fill slope zone. Final slope shaping should be performed by trimming and removing loose materials with appropriate equipment. Afinal determination of fill slope compaction should be based on observation and/or testing of the finished slope face. Where compacted fill slopes are designed steeper than 2:1 (horizontal to vertical), specific material types, a higher minimum relative compaction, and special grading procedures, may be recommended. If an alternative to over-building and cutting back the compacted fill slopes is selected, then special effort should be made to achieve the required compaction in the outer 10 feet of each lift of fill by undertaking the following: 1. An extra piece of equipment consisting of a heavy short shanked sheepsfoot should be used to roll (horizontal) parallel to the slopes continuously as fill is placed. The sheepsfoot roller should also be used to roll perpendicular to the slopes, and extend out over the slope to provide adequate compaction to the face of the slope. 2. Loose fill should not be spilled out over the face of the slope as each lift is compacted. Any loose fill spilled over a previously completed slope face should be trimmed off or be subject to re-rolling. 3. Field compaction tests will be made in the outer (horizontal) 2 to 8 feet of the slope at appropriate vertical intervals, subsequent to compaction operations. 4. After completion of the slope, the slope face should be shaped with a small tractor and then re-rolled with a sheepsfoot to achieve compaction to near the slope face. Subsequent to testing to verify compaction, the slopes should be grid-rolled to achieve compaction to the slope face. Final testing should be used to confirm compaction after grid rolling. 5. Where testing indicates less than adequate compaction, the contractor will be responsible to rip, water, mix and re-compact the slope material as necessary to achieve compaction. Additional testing should be performed to verify compaction. SCI Enterprises, LLC Appendix E Rle:e:\wp7\3400\3401a.pge Page 5 GeoSoils, Inc. 6. Erosion control and drainage devices should be designed by the project civil engineer in compliance with ordinances of the controlling governmental agencies, and/or in accordance with the recommendation of the soil engineer or engineering geologist. SUBDRAIN INSTALLATION Subdrains should be installed in approved ground in accordance with the approximate alignment and details indicated by the geotechnical consultant. Subdrain locations or materials should not be changed or modified without approval of the geotechnical consultant. The soil engineer and/or engineering geologist may recommend and direct changes in subdrain line, grade and drain material in the field, pending exposed conditions. The location of constructed subdrains should be recorded by the project civil engineer. EXCAVATIONS Excavations and cut slopes should be examined during grading by the engineering geologist. If directed by the engineering geologist, further excavations or overexcavation and re-filling of cut areas should be performed and/or remedial grading of cut slopes should be performed. When fill over cut slopes are to be graded, unless otherwise approved, the cut portion of the slope should be observed by the engineering geologist prior to placement of materials for construction of the fill portion of the slope. The engineering geologist should observe all cut slopes and should be notified by the contractor when cut slopes are started. If, during the course of grading, unforeseen adverse or potential adverse geologic conditions are encountered, the engineering geologist and soil engineer should investigate, evaluate and make recommendations to treat these problems. The need for cut slope buttressing or stabilizing should be based on in-grading evaluation by the engineering geologist, whether anticipated or not. Unless otherwise specified in soil and geological reports, no cut slopes should be excavated higher or steeper than that allowed by the ordinances of controlling governmental agencies. Additionally, short-term stability of temporary cut slopes is the contractors responsibility. Erosion control and drainage devices should be designed by the project civil engineer and should be constructed in compliance with the ordinances of the controlling governmental agencies, and/or in accordance with the recommendations of the soil engineer or engineering geologist. SCI Enterprises, LLC Appendix E File:e:\wp7\3400\3401a.pge Page 6 GeoSoils, Inc. COMPLETION Observation, testing and consultation by the geotechnical consultant should be conducted during the grading operations in order to state an opinion that all cut and filled areas are graded in accordance with the approved project specifications. After completion of grading and after the soil engineer and engineering geologist have finished their observations of the work, final reports should be submitted subject to review by the controlling governmental agencies. No further excavation or filling should be undertaken without prior notification of the soil engineer and/or engineering geologist. All finished cut and fill slopes should be protected from erosion and/or be planted in accordance with the project specifications and/or as recommended by a landscape architect. Such protection and/or planning should be undertaken as soon as practical after completion of grading. JOB SAFETY General At GeoSoils, Inc. (GSI) getting the job done safely is of primary concern. The following is the company's safety considerations for use by all employees on multi-employer construction sites. On ground personnel are at highest risk of injury and possible fatality on grading and construction projects. GSI recognizes that construction activities will vary on each site and that site safety is the prime responsibility of the contractor; however, everyone must be safety conscious and responsible at all times. To achieve our goal of avoiding accidents, cooperation between the client, the contractor and GSI personnel must be maintained. In an effort to minimize risks associated with geotechnical testing and observation, the following precautions are to be implemented for the safety of field personnel on grading and construction projects: Safety Meetings: GSI field personnel are directed to attend contractors regularly scheduled and documented safety meetings. Safety Vests: Safety vests are provided for and are to be worn by GSI personnel at all times when they are working in the field. Safety Flags: Two safety flags are provided to GSI field technicians; one is to be affixed to the vehicle when on site, the other is to be placed atop the spoil pile on all test pits. SCI Enterprises, LLC Appendix E File:e:\wp7\3400\3401a.pge Page 7 GeoSoils, Inc. Flashing Lights: All vehicles stationary in the grading area shall use rotating or flashing amber beacon, or strobe lights, on the vehicle during all field testing. While operating a vehicle in the grading area, the emergency flasher on the vehicle shall be activated. In the event that the contractor's representative observes any of our personnel not following the above, we request that it be brought to the attention of our office. Test Pits Location. Orientation and Clearance The technician is responsible for selecting test pit locations. A primary concern should be the technicians's safety. Efforts will be made to coordinate locations with the grading contractors authorized representative, and to select locations following or behind the established traffic pattern, preferably outside of current traffic. The contractors authorized representative (dump man, operator, supervisor, grade checker, etc.) should direct excavation of the pit and safety during the test period. Of paramount concern should be the soil technicians safety and obtaining enough tests to represent the fill. Test pits should be excavated so that the spoil pile is placed away form oncoming traffic, whenever possible. The technician's vehicle is to be placed next to the test pit, opposite the spoil pile. This necessitates the fill be maintained in adriveable condition. Alternatively, the contractor may wish to park a piece of equipment in front of the test holes, particularly in small fill areas or those with limited access. A zone of non-encroachment should be established for all test pits. No grading equipment should enter this zone during the testing procedure. The zone should extend approximately 50 feet outward from the center of the test pit. This zone is established for safety and to avoid excessive ground vibration which typically decreased test results. When taking slope tests the technician should park the vehicle directly above or below the test location. If this is not possible, a prominent flag should be placed at the top of the slope. The contractor's representative should effectively keep all equipment at a safe operation distance (e.g., 50 feet) away from the slope during this testing. The technician is directed to withdraw from the active portion of the fill as soon as possible following testing. The technician's vehicle should be parked at the perimeter of the fill in a highly visible location, well away from the equipment traffic pattern. The contractor should inform our personnel of all changes to haul roads, cut and fill areas or other factors that may affect site access and site safety. In the event that the technicians safety is jeopardized or compromised as a result of the contractors failure to comply with any of the above, the technician is required, by company policy, to immediately withdraw and notify his/her supervisor. The grading contractors representative will eventually be contacted in an effort to effect a solution. However, in the interim, no further testing will be performed until the situation is rectified. Any fill place can be considered unacceptable and subject to reprocessing, recompaction or removal. SCI Enterprises, LLC Appendix E Rle:e:\wpA3400\3401a.pge Page 8 GeoSoils, Inc. In the event that the soil technician does not comply with the above or other established safety guidelines, we request that the contractor brings this to his/her attention and notify this office. Effective communication and coordination between the contractors representative and the soils technician is strongly encouraged in order to implement the above safety plan. Trench and Vertical Excavation It is the contractor's responsibility to provide safe access into trenches where compaction testing is needed. Our personnel are directed not to enter any excavation or vertical cut which: 1) is 5 feet or deeper unless shored or laid back; 2) displays any evidence of instability, has any loose rock or other debris which could fall into the trench; or 3) displays any other evidence of any unsafe conditions regardless of depth. All trench excavations or vertical cuts in excess of 5 feet deep, which any person enters, should be shored or laid back. Trench access should be provided in accordance with CAL-OSHA and/or state and local standards. Our personnel are directed not to enter any trench by being lowered or "riding down" on the equipment. If the contractor fails to provide safe access to trenches for compaction testing, our company policy requires that the soil technician withdraw and notify his/her supervisor. The contractors representative will eventually be contacted in an effort to effect a solution. All backfill not tested due to safety concerns or other reasons could be subject to reprocessing and/or removal. If GSI personnel become aware of anyone working beneath an unsafe trench wall or vertical excavation, we have a legal obligation to put the contractor and owner/developer on notice to immediately correct the situation. If corrective steps are not taken, GSI then has an obligation to notify CAL-OSHA and/or the proper authorities. SCI Enterprises, LLC Appendix E File:e:\wp7\3400\3401a.pge Page 9 GeoSoils, Inc. CANYON SUBDRAIN DETAIL TYPE A PROPOSED COMPACTED FILL NATURAL GROUND TYPICAL BENCHING SEE ALTERNATIVES TYPE_I3 PROPOSED COMPACTED RLL •NATURAL GROUND COLLUVIUM AND ALLUVIUM 1REMOVEJ ,x •/J ^W^s TYPICAL BENCHING t BEDROCK ALTERNATIVES NOTE: ALTERNATIVES, LOCATION AND EXTENT OF SUBDRAINS SHOULD BE DETERMINED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST DURING GRADING. PLATE EG-1 CANYON SUBDRAIN ALTERNATE DETAILS ALTERNATE 1: PERFORATED PIPE AND FILTER MATERIAL A-1 MINIMUM FILTER MATERIAL MINIMUM VOLUME OF 9 FT." /LINEAR FT. 6' 4 ABS OR PYC PIPE OR APPROVED SUBSTITUTE WITH MINIMUM 8 11/4" 0 PERFS. LINEAR FT. IN BOTTOM HALF OF PIPE. ASTM 02751. SDR 35 OR ASTM 01527, SCHD, 40 ASTM D3034. SDR 35 OR ASTM 01785* SCHD. 40FOR CONTINUOUS RUN IN EXCESS OF 500 FT. USE 8'tf PIPE 6" MINIMUMB-1 FILTER MATERIAL. SIZE 1 INCH 3/4 INCH 3/8 INCH NO. 4 NO. 8 .NO. 30 "NO. 50 NO. 200 PERCENT PASSING ,100 90-100 40-100 25-40. 18-33 -.5-15 .0-7 0-3 ALTERNATE 2: PERFORATED PIPE, GRAVEL AND.FILTER FABRIC MINIMUM OVERLAP 6- MINIMUM COVER 4- MINIMUM BEDDING 6- MINIMUM OVERLAP 4* MINIMUM BEDDING A-2 GRAVEL'MATERIAL 9 FTVLINEAR FT. PERFORATED PIPE SEE ALTERNATE 1 GRAVEL CLEAN 3/4 INCH ROCK OR APPROVED SUBSTITUTE FILTER FABRIC MIRAFI 140 OR APPROVED SUBSTITUTE PLATE EG-2 DETAIL FOR FILL SLOPE TOEING OUT ON FLAT ALLUVIATED CANYON TOE OF SLOPE AS SHOWN ON GRADING PLAN .ORIGINAL GROUND SURFACE TO BE RESTORED WITH COMPACTED FILL BACKCUTVvARIES. FOR DEEP REMOVALS. BACKCUT ^VKSHOULD BE MADE NO STEEPER-THAJfco:l OR AS NECESSARY FOR SAFETY ^^^ ONSIDERATIONS COMPACTED FILL ORIGINAL GROUND SURFACE ANTICIPATED ALLUVIAL REMOVAL DEPTH PER SOIL ENGINEER. PROVIDE A 111 MINIMUM PROJECTION FROM TOE OF SLOPE AS SHOWN ON GRADING PLAN TO THE RECOMMENDED REMOVAL DEPTH. SLOPE HEIGHT. SITE CONDITIONS AMD/OR LOCAL CONDITIONS COULD DICTATE FLATTER PROJECTIONS. REMOVAL ADJACENT TO EXISTING FILL ADJOINING CANYON RLL PROPOSED ADDITIONAL COMPACTED FILL COMPACTED RLL LIMITS LINE TEMPORARY COMPACTED FILL FOR DRAINAGE ONLY Oaf IEXISTING..COMPACTED RLL) , Qal ITO BE REMOVED) %' —*"8B^ 0 BE REMOVED BEFORE PLACING ADDITIONAL COMPACTED FILL /* LEGEND Qaf ARTIFICIAL RLL Qal ALLUVIUM PLATE EG-3 UJ Q LL. CO COUJo: o CO 2 CL h- PLATE EG-4 1 •~^ 11 — UJ Q Z[ ~3^^j^^^^o:ION / BUTTRESS SUBDU MINIMUM OF FIVE FP/LINEAR Fl OF PIPF |h- -*~^ K •< S N < -J <r— . UJ DO £ CO §— I^>< LLO UJm• _i ^in _j< IT UJ K- ^<r UJi- MM n" z /• o 2 2 S P m in< _j mo ^ ^c 5 Q- S a zlil O ^ 5i u S 0 Ul g 1 °0 ? UJ -1 nl t LL 2 UJuj < g; X K — H 0 W NEAR Fl OF PIPE WHEN PLACED IN SQUARELIEU OF FILJER MATERIAL: GRAVEL MAY BE•** & j Z: s 2 o: ui K 1 CE. 7^'e ^ I>- ui5 3 ™0 CJ _1 0 oo oO v- ^.0 I I *~ 0 oOl -J- "T" ^BW log CJ Z 2 ^M— -» co n en PROVED FILTER FABRIC. FILTER FABRICFl HO OR EQUIVALENT. FILTER FABRIC'ED A MINIMUM OF 12' ON ALL JOINTS.ETER PIPE: ABS-ASTM D-2751. SDR 35a- < n 2:< £ < <z z -j a a ui ui •5 m CD M M* •«•in- _j _i •*•< _l _l =3 0 < < 2E•z- a: at =ui in in — Ul_ xo n in J± T ? T 7 T Urin oo in o o <-»(NT- QJ J Iin O _j ** " r> S 5 UJ. • f^1 > S S d d d 2z z z _ « o:^ ^ Z {3 27 SCHEDULE 40 PVC-ASTM D-303A.M D-17B5 SCHEDULE 40 WITH A CRUSHINGI.OOO POUNDS MINIMUM. AND A MINIMUM OFPACED PERFORATIONS PER FOOT OF PIPEH PERFORATIONS OF BOTTOM OF PIPE.T UPSTREAM END OF PIPE. SLOPE AT 2%E. OUTLET PIPE TO BE CONNECTED TO- »_ *- in £ < Q. T < | S * | = Jt, JJJ {^ "^ •*• ^^* ^* m «5 • ti «•» C3 ^^ 2 *•»•« 5 2 H g^t 0^ fu ^™ i^^ f* *•*C CC ""s ui ^* K Q. 1- 3 Z ? 2O W) W CD — OL H- U 0 S0 ^ Inz ^ mo , ^p uj .a. o > zLI 5 UJ oa.^ Ul LU g Si Q Q.1/1 LUo > m Z 0 N it55 0 0. uj^* ^r ^^_j ^. • > O Z —LL < W in LL O 2 o 2 ° in « Z Z LU ; ~"* ^ 3.O OS Z -» 0 3 "~ . CN O fN O . UJ »- ^ ^ Q .Z ^^~~ z in WITH TEE OR ELBOW.•CH FOR OUTLET PIPES TO BE BACKFILLEDiON-SITE SOIL.DRAINS AND LATERAL DRAINS SHALL BEFED AT ELEVATION OF EVERY BENCH DRAIN.DRAIN LOCATED AT ELEVATION JUST ABOVER LOT GRADE. ADDITIONAL DRAINS MAY BEIRED AT THE DISCRETION OF THE SOILSIEER AND/OR ENGINEERING GEOLOGIST.Ul ZT-5-rf*"LlJ31*:> Si uij-ooi23:oo CL trE<o££oUiz _ h-^m-JLL-lCEUJz < _•CC S idm |_ =3 5M Z . CH - ^^^^^ 2 nnwrniH^z | i|V S /$-— *'NV Z Oa. h- f ( 3 Z Z Z< y .*. -rr• «• • i:-:.-:-fl 1.4 PLATE EG-5 a UJ LL PLATE EG-6 LU Q O LLl O _J 01 az < aa z S 8I Icj a X Z LU LU LU £Ea a E Q.O 5 S U) LU {Z UI UI I/) * 5 IUI O UI £z =c ^ O »~ 0! K m 50 a °"0- ui H-1- H- 52n < o0=0 UI < OX > UII- UI U • •UIt-oz PLATE EG-7 52s §Ul -I« s sHb o cr CO S* O LU cr cro ° iu * i? I— Q. O EC O ZUl -J uiUl W3* eg 3 § S LU a g G < a u. ui iti ~ Zui < ui z »2 5ui H w Wl T* >- I OB Ul a *uj ui S 3Ul vt ui ac ui £ z Ul r~ 5 z s «u uj tA = I o tui S QB ^^— z> Ula ui ui < vt Ul Ul Ul -C X X &W I-? ifc < S 5a _ < o> x iur t- a LU O PLATE EG-8 Oa:o a: LL. PLATE EG-9 Ul CJ CO 3U) auitooa.xUl auiin m aui UII- Ula uim 03 > OC tninuiuuiz auiz z CC Ul Ula u. uiz K ui inn_ 5 ui °.D oa ui_i o > z M K? Ul Ulin a z uii- cc 2 zZ 3 I- 3ui m u zz cr < 5 g 2 5 ui1 £ s jE- ui o n| eeK w> « 2-^ w S 75 5 o o K >• S 5 SS " ^ z* a < 3 a 5 ° zz < x ui < £ w ui z o K =i 1 Ig 8a a °aa z a uto o < xw o a. H uiH O PLATE EG-10 TRANSITION LOT DETAIL CUT LOT (MATERIAL TYPE TRANSITION) NATURAL GRADE COMPACTED FILL OYEREXCAVATE AND RECOMPACT 0*W\\V^\M>^^ 3*MINIMUM* UNWEATHERED BEDROCK OR APPROVED MATERIAL TYPICAL BENCHING CUT-RLL LOT (DAYLIGHT TRANSITION) PAD GRADE NATURAL GRADE *™*£** fa-s' MINIMUM COMPACTED FILL 0* &&OVEREXCAVATE AND RECOMPACT ^ * X UNWEATHERED BEDROCK OR APPROVED MATERIAL TYPICAL BENCHING NOTE: * DEEPER OVEREXCAVATION MAY BE RECOMMENDED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST IN STEEP CUT-RLL TRANSITION AREAS. PLATE EG-1T SETTLEMENT PLATE AND RISER DETAIL 2'X 2'X I/A" STEEL PLATE ^STANDARD 3/4" PIPE NIPPLE WELDED TO TOP ^*^\ OF PLATE. ^~ —• 3/4- X 5' GALVANIZED PIPE, STANDARD PIPE N. THREAD STOP AND. BOTTOM. EXTENSIONS N. THREADED ON BOTH ENDS AND ADDED IN 5' X INCREMENTS. •3 INCH SCHEDULE 40 PVC PIPE SLEEVE. ADD IN 5* INCREMENTS WITH GLUE JOINTS. RNAL GRADE T j MAINTAIN 5' CLEARANCE OF HEAVY EQUIPMENT. _i_^. MECHANICALLY HAND COMPACT IN 2'VERTICAL LIFTS OR ALTERNATIVE SUITABLE TO AND ACCEPTED BY THE SOILS ENGINEER. MECHANICALLY HAND COMPACT THE INITIAL 5* VERTICAL WITHIN A 5'RADIUS OF PLATE BASE. BOTTOM OF CLEANOUT PROVIDE A MINIMUM V BEDDING OF COMPACTED SAND NOTE: 1.LOCATIONS OF SETTLEMENT PLATES SHOULD BE CLEARLY MARKED AND READILY VISIBLE (RED FLAGGED) TO EQUIPMENT OPERATORS. 2. CONTRACTOR SHOULD MAINTAIN CLEARANCE OF A 5* RADIUS OF PLATE BASE AND WITHIN 5'(VERTICAL! FOR HEAVY EQUIPMENT. RLL WITHIN CLEARANCE AREA SHOULD BE HAND" COMPACTED TO PROJECT SPECIFICATIONS OR COMPACTED BY ALTERNATIVE APPROVED BY THE SOILS ENGINEER. 3. AFTER S'tYERTICALJ OF RLL IS IN PLACE. CONTRACTOR SHOULD MAINTAIN A 51RADIUS EQUIPMENT CLEARANCE FROM RISER. 4. PLACE AND MECHANICALLY HAND COMPACT INITIAL 2' OF RLL PRIOR TO ESTABLISHING THE INITIAL READING. 5. IN THE EVENT OF DAMAGE TO THE SETTLEMENT PLATE OR EXTENSION RESULTING FROM EQUIPMENT OPERATING WITHIN THE SPECIFIED CLEARANCE AREA. CONTRACTOR SHOULD IMMEDIATELY NOTIFY THE SOILS ENGINEER AND SHOULD BE RESPONSIBLE FOR RESTORING THE SETTLEMENT PLATES TO WORKING ORDER. 5. AN ALTERNATE DESIGN AND METHOD OF INSTALLATION MAY BE PROVIDED AT THE DISCRETION OF THE SOILS ENGINEER. PLATE EG-U TYPICAL SURFACE SETTLEMENT MONUMENT FINISH GRADE k-6- DIAMETER X 3 1/2* LENGTH HOLE 3/8' DIAMETER X 6' LENGTH CARRIAGE BOLT OR EQUIVALENT CONCRETE BACKFILL PLATE EG-15 TEST PIT SAFETY DIAGRAM SIDE VIEW mm TEST RT msP- ( NOT TO SCALE ) TOP VIEW 100 FEET APPROXIMATE CEHTfeK OF TEST PIT { NOT TO SCALE ) PI ATP EG—16 OVERSIZE ROCK DISPOSAL VIEW NORMAL TO SLOPE FACE PROPOSED FINISH GRADE )' MINIMUM (E) CO OO 15* MINIMUM (A) 20'MINIMUM oo _^J 5* MINIMUM U ao oo (G) fe*MINIMUM (C) CO AWxX^X^^^BEDROCK OR APPROVED MATERIAL VIEW PARALLEL TO SLOPE FACE PROPOSED FINISH GRADE I I 10* MINIMUM (E),100* MAXIMUM tBLi- -jljr-1-V --^^-rr3 0OGO3QOOOOO0C? 15* MINIMUM I* MINIMUM (G) FROM BEDROCK OR APPROVED MATERIAL NOTE: (A) ONE EQUIPMENT WIDTH OR A MINIMUM OF 15 FEET. (B) HEIGHT AND WIDTH MAY VARY DEPENDING ON ROCK SEE AND TYPE OF EQUIPMENT. LENGTH OF WINDROW SHALL BE NO GREATER THAN 100'MAXIMUM. 1C) IF APPROVED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST. WINDROWS MAY BE PLACED DIRECTLY ON COMPETENT MATERIAL OR BEDROCK PROVIDED ADEQUATE SPACE IS AVAILABLE FOR COMPACTION. ~ (D) ORIENTATION OF WINDROWS MAY VARY BUT SHOULD BE AS RECOMMENDED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST. STAGGERING OF WINDROWS IS NOT NECESSARY UNLESS RECOMMENDED. IE) CLEAR AREA FOR UTILITY TRENCHES. FOUNDATIONS AND SWIMMING POOLS. IF) ALL FILL OVER AND AROUND ROCK WINDROW SHALL BE COMPACTED TO 90% RELATIVE COMPACTION OR AS RECOMMENDED. (G) AFTER FILL BETWEEN WINDROWS IS PLACED AND COMPACTED WITH THE LIFT OF FILL COVERING WINDROW, WINDROW SHOULD BE PROOF ROLLED WITH A D-9 DOZER OR EQUIVALENT. VIEWS ARE DIAGRAMMATIC ONLY. ROCK SHOULD NOT TOUCH _ AND VOIDS SHOULD BE COMPLETELY FILLED IN. PLATE RD~1 ROCK DISPOSAL PITS VIEWS ARE DIAGRAMMATIC ONLY. ROCK SHOULD NOT TOUCH AND VOIDS SHOULD BE COMPLETELY FILLED IN. FILL LIFTS COMPACTED OVER ROCK AFTER EMBEDMENT ! <T.i. GRANULAR MATERIAL SIZE OF EXCAVATION TO BE COMMENSURATE WITH ROCK SIZE | ROCK DISPOSAL LAYERS GRANULAR SOIL TO FILL VOIDS. DENSIRED BY FLOODING ^ . *T*LAYER ONE ROCK HIGH U COMPACTED FILLx wumi-Auicu I-IU. ^- jf _i.T?*-^7l^^Xr.">r~Xrf—»CVP—«^. I'PROPOSED FINISH GRADE 10' MINIMUM OR BELOW LOWEST UTIU PROFILE ALONG LAYER LOPE FACE L FILL \ 1 SLOPE \ }\* _j i CLEAR ZONE 20'MINIMUM LAYER ONE ROCK HIGH PLATE RD-2