Loading...
HomeMy WebLinkAboutGeotechnical Report I (t) I Converse Consultants Over 50 Years of Dedication in Geotechnical Engineering and Environmental Sciences I I I I I GEOTECHNICAL INVESTIGATION REPORT Proposed Residential Development 9.75-Acre site, Tract 29286 I City of Temecula, California I I I RECFI\f!=~.; JAN 21 2000 I CITY Or I ru,... I. ENGINEERING DEPAflTiv,:",. I . I Prepared for: I Lennar Communities 24800 Chrisanta Drive I Mission Viejo, CA 92691 Converse Project No. 99-81-305-01 I January 20, 2000 I 10391 Corporate Drive, Redlands. California 92374 \ OPnnlfton Telephone: (909) 796-0544 . Facsimile: (909) 796-7675 . e-mail: ccieconv@aol.com RecJcled Fap., II I I I I I I I I I I I I · I I I I I I (t) Converse Consultants Over 60 Years of Dedication in Geotechnical Engineering and Environmental Sciences January 20, 2000 Mr. Bill Storm Project Director California Land Division Lennar Communities 24800 Chrisanta Drive Mission Viejo, CA 92691 Subject: GEOTECHNICAL INVESTIGATION REPORT Tentative Tract 29286 (9.75-Acre Site) Southeast Corner of Date street and Margarita Road City of Temecula, California Converse Project No. 99-81-305-01 Dear Mr. Storm: Converse Consultants (Converse) has prepared this report to present the findings of our geotechnical exploration performed for the proposed residential housing development (Tentative Tract 29286) located in city of Temecula, California. This report is prepared in accordance with our proposal dated December 1, 1999 and your authorization dated December 21, 1999. Based on our findings, it is our opinion that the project site is suitable for the proposed residential development, provided the findings and conclusions presented in this geotechnical report are considered in the planning, design and construction of the project. We suggest that converse should review the final grading plan to verify compliance with our assumptions. If needed, we will update our geotechnical report to address the grading design recommendations. If you have any questions regarding this report, please feel free to contact us at (909) 796-0544. This opportunity to be of service to Lennar Communities is greatly appreciated. CONVERSE CONSULT ANTf Hashmi S. E. Quazi, Ph.D., P. E. Senior Vice President/Principal Engineer Dist.: 3/ Addressee 3/ Robert Bein, William Frost & Associates KN K/HSQ/bac\mjr O Pnnl.-d on R"cJcled PalM' 10391 Corporate Drive, Redlands, California 92374 Telephone: (909) 796-0544 . Facsimile: (909) 796-7675 . e-mail: ccieconv@aol.com -z.. I I I I I I I I I I II I . . I I I I I 99-81-305-01 January 20, 2000 Page ii EXECUTIVE SUMMARY The following is a summary of our geotechnical investigation, conclusions and recommendations, as presented in the body of this report. Please refer to the appropriate sections of the report for complete conclusions and recommendations. In the event of a conflict between this summary and the report, or an omission in the summary, the report shall prevail. · The site investigation was completed on December 20, 1999, and results of our investigation- indicate that the site- is suitable from a geotechnical standpoint for the proposed residential development provided the recommendations presented in this and subsequent geotechnical reports if needed are considered in the planning, design and construction. · A total of 5 exploratory borings and 8 test pits were excavated within the project site. The depth of the borings ranged from 21.5 to 51.5 feet below existing ground surface. The test pits were excavated using a backhoe equipped with a 24-inch-wide bucket to depths ranging from 4 to 1 2 feet below existing ground surface. · Pauba formation bedrock alluvial soil and artificial fill underlie the project site. The thickness of the alluvial soil range from 0 to 10.0 feet. The undocumented fill in the site range from approximately 0 to 5.0 feet thick. · Alluvial deposits and Pauba bedrock underlie the project site. The thickness of the alluvial soil range from 0 to 10.0 feet. · The site soils encountered at the project site exhibited negligible to moderate . collapse potential. · Site soils have very low expansion potential. · Site soils are moderately to severely corrosive to ferrous metal and are generally not deleterious to concrete structures. Type I or II Portland Cement may be used for concrete construction. All undocumented fills should be removed and compacted. · Site grading, in general, should include removal and replacement as processed compacted fills for the upper three (3) to five (5) feet of disturbed alluvial deposits. Deeper removal may be required along some localized areas. · Earth materials at the site should be excavatable with conventional earth moving equipment. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305\99-305-1-.9ir 7 I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page iii · The proposed fill/cut slopes with slopes 2:1 (H:V) are grossly stable under static as well as earthquake loading conditions. · Groundwater was not encountered during the exploration that drilled to a maximum depth of 51.5 feet below existing ground surface. Based on available information, the depth to groundwater within the general vicinity of the project site is deeper than 150 feet below existing ground surface. · The site is not located within a currently designated State of California Earthquake Fault Zone:- The nearest known active fault designated as the State of California Earthquake Fault Zone and capable of generating significant ground motion at the site is the Wildomar (Temecula) Fault. This full segment is located approximately three (3) miles southwest of this site. . The Elsinore-Wildomar (Temecula) Fault is considered to have the greatest potential to have an impact at the project site. Based on a deterministic seismic hazard analysis, the project site may experience a peak horizontal ground acceleration on the order of 0.59g, where g is the acceleration due to gravity, due to a maximum credible earthquake of moment magnitude of 6.8 associated with the Elsinore Fault. . The project site is not susceptible to soil liquefaction during earthquakes. . The potential of seismic hazards due to the secondary effects of earthquakes including seismically induced ground settlement and differential settlement, lateral spreading, landslides, earthquake induced flooding is considered to be very low to low. Based on the site location, tsunamis or seiches do not pose a hazard. . One- or two- story residential structures may be supported on conventional footing foundations. Concrete slabs-on-grade for such buildings may be of the conventional type as opposed to grade-beam or post-tensioned types. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.9Ir A.. I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page iv PROFESSIONAL CERTIFICATION This report has been prepared by the staff of Converse Consultants under the professional supervision of the following individuals whose seals and signatures appear hereon. The findings, recommendations, specifications and professional opinions contained in this report were prepared in accordance with the generally accepted professional engineering and engineering geologic principle and practice in this area of Southern California. We make no other warranty, either expressed or implied. , '0lI~ f) &A- Kugan Kuganenthira, Ph.D. Project Engineer Michael O. Cook, C. E. G. 1716 Project Geologist , -, \ . Hashmi S. E. Quazi, Ph. D., P. E. Senior Vice President/Principal Engineer ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-pre.gir I I 99.81-305-01 January 20. 2000 Page v I I I I . I I I CONTENTS 1 .0 INTRODUCTION...........................................................................................................................................1 2.0 PROJECT DESCRiPTION............................................................................................................................1 3.0 SITE DESCRIPTION .....................................................................................................................................2 3. 1 SITE LOCATION AN D BOUN DARIES..................... .........,................................................................................... 2 3. 2 SURFACE CONDITIO NS ..................................................... ..........................,.......................................,............ 2 4.0 SCOPE- OF WORK .....................~......::.........................................................................................................2 I I I I I I I I I 4. 1 FI ELD EXPLORATION.................................... .................................................................................................... 2 4.2 LABORATORY TEST I NG ................................. .................................................................................................. 3 4.3 REPO RT PREPARATION...................................... ........................... ................................................................... 4 5.0 SITE CONDITIONS ...................................................................................................................................... 4 5. 1 G EOLOG IC SETTING ....................................................'......,............................................................................. 4 5.2 SITE GEOLOGY ......... ..................................................,..............................,....................,...,.'.......................... 4 5.2./ Pauba Formation (Map Symbol Qp) ................. ................ ......u........................... ....5 5.2.2 Recent Alluvium (Map Symbol Qal).... ................ ......... ..............5 5.2.3 Artificial Fill (Map Symbol Aj).......................... ...................... ....................... 5 5.3 EXCA VAT ABI L1TY ..............................................................................,.......................................................,. ....' 5 5.4 S U BSU RF ACE CONDITIONSIPROFI LE...............................................,.,........................ .............................. ........ 6 5.5 COLLAPSE/Exp ANSIO N POTENTIAL.......................................................................... ......... u........................... 6 5.6 SO I L CO RRO SIVITY ..................................................................................................... ....................................6 5.7 SHRI NKAGE AND SUBSI DENCE.............................................................. .............................. ............................. 8 5.8 G ROUNDW A TER ......................... ................. ............................................... ..................................................... 8 5.9 SLOPE STABILITy........... :.......... ........................ ............................................ ................................ ................... 8 5.10 SUBSURFACE VARIATIONS .............................................................u.............................................................. 9 6.0 FAULTING AND SEISMICITY ...................................................................................................................9 6. 1 FAULTING.................................................................................................................... ....................................9 6.2 SEiSMiCiTy.................................................................................................... u....:......... ................................ 10 6.2.1 Historical Data Analysis ................... . ...",.................................,...."..........................,..,...........12 6.3 LIQUEFACTION EVALUATION .........................................................................................................................12 6.4 SECONDARY HAZARDS DUE TO SEISMIC ACTIVITY ......................uu............................................................12 7.0 CONCLUSIONS ..........................................................................................................................................13 8.0 EARTHWORK/SITE GRADING RECOMMENDATIONS......................................................................14 8. 1 GENERAL.......................................................,....................................................................... ......................... 14 8.2 REMOV Al/OVERExCA V A TION ......................,............................................................... ................................. 15 8.3 TEMPORARY SLOPED EXCAVATIONS ...................................,...........................................................u...........16 8.4 SITE ORAl NAG E . .....................................,.....,.. u.........,..........,....................................................................... 16 8.5 SLOPE PROTECTION AND MAINTENANCE......................................................................................................17 ~ W Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81\99-305\99-305-1'.9ir -'l I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page vi 9.0 9.1 9.2 9.3 9.4 9.5 10.0 STRUCTURAL DESIGN RECOMMENDA TIONSECTION ....................................................................18 FOUNOA TION DESIGN PARAMETERS....................................... ..................................................................... 18 LATERAL EARTH PRESSURE.......................................................................................................................... 18 LATERAL RESiSTANCE................. .................................................................................................................. 18 SETTLEMENT................................................................................................................................. ................. 19 SLABS-O N-GRAOE .......................................................................................................................... ............... 19 BURIED UTILITY, PAVEMENT AND CONSTRUCTION RECOMMENDA TIONS.20 10.1 BURIEO UTILITY TRENCH BACKFILL..................................u......................................................................20 10.1.1 General. .......... ......... .... ....... ...... ...... ....u.... ................. ...................... .......................... ..20 10.1.2 Pipe Bedding................... .............................................. ...............:.............20 10. 2 ASPHALT PAVEMENT ........................................................................................ .......... .............................. 21 11.0 GEOTECHNICAL SERVICES DURING CONSTRUCTlON.......................................................................22 12.0 CLOSURE ....................................................................................................................................................22 13.0 REFERENCES..............................................................................................................................................24 APPENDICES APPENDIX A ........................................................................FIELD EXPLORATION APPENDIX B.................................................................... LABORATORY TESTING APPENDIX C.................................RECOMMENDED EARTHWORK SPECIFICATIONS APPENDIX D...........................................................SLOPE STABILITY ANALYSIS TABLES TABLE NO.1, REQUIREMENTS FOR CONCRETE EXPOSED TO SULFATE-CONTAINING SOLUTIONS ......7 TABLE NO.2, SEISMIC CHARACTERISTICS OF REGIONAL FAULTS.......................................... 10 TABLE NO.3, TEMPORARY EXCAVATION SLOPES ..............................................................16 TABLE No.4, RECOMMENDED PRELIMINARY STRUCTURAL SECTIONS FOR FLEXIBLE PAVEMENT 21 ILLUSTRA TIONS Figures Following Page No.: Figure No.1, Site Location Map ...................................................................................... 1 Figure No.2, Fault Map ............................................................................................... 10 Figure No.3, Earthquake Epicenter Map ........................................................................ 10 Drawing No.1, Approximate Boring and Test Pit Location Map............................ In pocket ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.9Ir ~ I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 1 1.0 INTRODUCTION This report presents the results of a geotechnical investigation performed for a 9.75- acre site, located at the southeast corner of Date Street and Margarita Road in the city of Temecula, California. The location of the site is shown in Figure No.1, Site Location Map. The subject site, designated as Tentative Tract No. 29286, is proposed to be developed as a residential housing complex, Our investigation was performed in accordance with the scope of work outlined in our proposal dated December 1, 1999. The purposes of this investigation were to determine the nature and engineering properties of the subsurface soils and to provide recommendations regarding general site grading and engineering recommendations for design and construction of foundations for single family housing structures and various facilities generally associated with residential developments. A map, Tentative Tract No. 29286, City of Temecu/a, dated November 9, 1999, Scale 1" = 40'; prepared by Robert Bein, William Frost & Associates, Temecula, California, was used as a base for our investigation. This report is written for the proposed residential development project as presented on the tract map provided and described herein and is intended for use solely by the Lennar Communities and its authorized agents. It should not be used as a bidding document but may be made available to the potential contractors for information on factual data only. For bidding purposes, the contractors should be responsible for making their own interpretation of the data contained in this report. 2.0 PROJECT DESCRIPTION The subject site is proposed to be developed as a residential housing tract. It is our understanding that the development will include both one- and two-story residential buildings, construction of streets, driveways, curb and gutter, sidewalks, landscape areas, utilities including storm drain, sewer, water, gas pipelines, electrical lines and other appurtenant facilities usually associated with such development. Site development may include slopes and earth retaining walls. The residences are likely to be of wood-frame and stucco structures founded on continuous and/or isolated footing foundations with slabs-on-grade. The vertical loads on continuous and isolated footing foundations are anticipated to be less than 2,000 pounds per linear foot and 50,000 pounds, respectively. Pertinent geologic and geotechnical data, including the approximate locations of the ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.9ir <'\. I I I I I I I I I I I I I I I I I I I Reference: C.D.M.G.Murrieta Quadrangle 7.5 MINUTE SERIES Photorevised 1979 SCALE. 1:24,000 SITE LOCATION MAP PROPOSED RESIDENTIAL DEVELOPMENT, TENTATIVE. TRACT 29286 City ofTemecula, California . For: Lennar Homes Project No. 99-81-305-01 @ Converse Consultants Figure No. 1 ~ I I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 2 exploratory borings drilled and test pits excavated are shown on Drawing No.1, Approximate Boring and Test Pit Location Map. Based on the grading plan, cut and fill slopes are not expected to be graded steeper than 2:1 (horizontal: vertical) and are not expected to exceed 20 feet in height. The maximum height of fill within the site is not expected to exceed maximum of 10 feet. Maximum cuts at the knobs of hills within site are expected to be on the order of 40 feet. 3.0 SITE DESCRIPTION 3. 1 Site Location and Boundaries The project site, as shown in Figure No.1, Site Location Map, consists of 9.75 acres of undeveloped land. The approximately rectangular shaped site is bounded on the northwest by Date Street the southwest by Margarita Road, northeast by an existing residential development and southeast by Winchester Creek Park. The site is located approximately one (1) mile east of Interstate 15. An existing 42" RCP storm drain pipe was observed in the southern portion of the lots No. 33 and 34. Based on the information provided in the grading plan, this drain pipe will be abandoned during grading. 3.2 Surface Conditions Topographically the site is characterized as rounded hills with a shallow valley adjacent to Date Street and Margarita Road. The surface elevation increases from approximately 1,115 feet above Mean Sea Level (MSL) in the northwest corner to approximately 1,162 feet MSL in the southeast corner portion. A dirt road crosses approximately along the central portion of the site. Existing fill placed during construction of Margarita Road, Date Street and the adjacent residential development is present in the general area of Lots 25 through 36. 4.0 SCOPE OF WORK The scope of this investigation includes field exploration, laboratory testing, analysis and interpretation of data and preparation of this report. 4. 1 Field Exploration Our field exploration included a site reconnaissance by a project engineer and a project engineering geologist. The purpose of the site reconnaissance was to observe surface conditions and to select exploratory boring and test pit locations. The ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.glr <\ I I. I I I I I I I I I . I I I I I I I 99-81-305-01 January 20. 2000 Page 3 locations of the borings and test pits are shown In Drawing No.1, Approximate Boring and Test Pit Location Map. A total of five (5) exploratory borings (BH-1 through BH-5) and 8 exploratory test pits (TP-1 through TP-8) were excavated within the project site. The borings were drilled using a six-inch hollow-stem auger drill rig. The depth of the borings ranged from 21.5 feet to 51.5 feet below existing ground surface. The test pits were excavated using a backhoe equipped with a 24-inch-wide bucket to depths ranging from 4 to 12 feet below existing ground surface. The subsurface conditions encountered in the exploratory borings and test pits were visually logged. Relatively undisturbed ring and bulk samples of the representative subsurface materials were obtained from the borings and the test pits at frequent depth intervals for the purpose of field identification and laboratory testing. A more detailed description of the field exploration procedures and logs of borings and test pits are presented in Appendix A, Field Exploration. 4.2 Laboratory Testing Representative samples of the site soils were tested in the laboratory (1) to aid in the classification and (2) to evaluate relevant engineering properties of the site soils. These tests includes: . In situ moisture contents (ASTM Standard D2216-80) and dry density . Gradation analysis (ASTM Standard D422-63) . Maximum dry density and optimum moisture content relationship (ASTM Standard D1557-91 ) . Direct shear (ASTM Standard D3080-90) . Collapse (ASTM Standard D5333-92) . Consolidation (ASTM Standard D2435-96) . Expansion Index (ASTM Standard D4829-88) . R-value (California Test Method No. 301-G) . Soil corrosivity (ASTM Standards D512, D513, G516, Dl125, Dl126, D2791, G51 and G57) ~ ~ Converse Consultants CCIENT\OFFICEIJOBFILEI 1999181 199-305199-305-1-.gir \() il I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 4 For a description of the laboratory test methods and test results, see Appendix B, Laboratory Testing Program. For in-situ moisture and density data, see the logs of boring and test pits in Appendix A, Field Exploration. 4.3 Report Preparation Data obtained from the field exploration and laboratory testing program were compiled and evaluated. Geotechnical analyses of the compiled data was performed and this report was prepared to present our findings, conclusions and recommendations for the proposed- project. 5.0 SITE CONDITIONS A general description of the regional and site-specific geologic information is presented in this section. Also presented in this section is a description of the subsurface conditions, various materials and groundwater conditions encountered at the site during field exploration. 5. 1 Geologic Setting The site is situated within the Peninsular Ranges Geomorphic Province of Southern California, which is an area that extends from the San Gabriel Mountains southeasterly into Baja California, Mexico. This Geomorphic Province is characterized by northwesterly trending mountain ranges bounded by systems of northwesterly trending faults and alluvial-filled basins. The project area lies near the southwestern edge of the Perris Block, a northwest-trending structural block that lies between the Elsinore Fault Zone on the southwest and the San Jacinto Fault Zone on the northeast. The Perris Block is characterized by Mesozoic metamorphic and plutonic rock and Cenozoic sedimentary and volcanic rock formations that form hills of low to moderate relief. The subject site is underlain by late Pleistocene Pauba Formation siltstone, sandstone and conglomerate. 5.2 Site Geology Quaternary-age Pauba Formation bedrock, recent Alluvium and artificial fill underlie the project site. The Pauba Formation bedrock is primarily an arkosic sandstone with interbeds of clayey sandstone and silty claystone. The bedrock is massive to thickly bedded. Recent alluvium is present within the natural drainage adjacent to Date Street and Margarita Road. Artificial fill was present adjacent to Date Street and Margarita Road and in the Northern corner of the site. Undocumented fill is present adjacent to dirt road that approximate mid portion of the site. a>- ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81\99-305\99-305-1-.9ir \\. I I I I I I I I I I I I I I I I il I I 99-81-305-01 January 20, 2000 Page 5 These geologic units consist of arkosic sandstone with interbedded clayey sandstone and silty claystone; silty sand, clayey sand and fine grained silty and clayey sands. Areal distribution of the earth materials is shown on Drawing No.1, Approximate Boring and Test Pit Location Map. These materials are described below from geologically oldest to youngest. 5.2.1 Pauba Formation (Map Symbol Qp) The Pauba Formation of late Pleistocene Age (Kennedy, 1977) underlies the site. In general, the formation consists of distal alluvial fan and braided channel deposits, with numerous intra-formation unconformities. Sedimentary features characteristic of the depositional environment such as channel lag, scour and fill and cross-bedding were observed in test pit and boring exposures. Within the subject site, lithology of the Pauba Formation is highly variable, consisting of poorly interbedded to massive, moderately to well consolidated, fine to coarse- grained sandstone. The sandstone is alluvial channel-type deposits with lenses of gravelly sandstone, siltstone and silty claystone. 5.2.2 Recent Alluvium (Map Symbol Qal) Recent alluvium was encountered within narrow drainage channels/ravines as shown on Drawing No.1, Approximate Boring and Test Pit Location Map. Alluvium up to depths of 10 feet underlies the northwestern part of the site. These materials were classified as silty sand, clay, and silt. The alluvium was dry to moist, loose to medium-dense, and contained slightly porous voids. 5.2.3 Artificial Fill (Map Symbol Af) Artificial fill is present along the southern, western, and northern perimeter of the site. The perimeter fills were placed as part of construction/grading of Date Street, Margarita Road and a fill slope for the residential development on the southeast portion of the site. Undocumented fill soils are present adjacent, to the dirt road which crosses the central portion of the street. These fill soils are spoils piles produced during grading of the dirt road. 5.3 Excavatability Based on the results of this field exploration and experience similar adjacent grading sites, site soils should be excavatable with conventional heavy-duty grading equipment. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.gir \7.- I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 6 5.4 Subsurface Conditions/Profile According to our subsurface data, the proposed development is underlain by alluvial deposits consisting of silty sand, clayey silt, silt, clay and Pauba Formation. The in- situ dry density of the soils and bedrock ranges from 74 pounds per cubic foot (pcf) to 130 pcf and the moisture content ranges from one (1) to 44 percent. The variations of blow count, dry density and water content of on-site earth materials versus elevation are presented in Drawings No. A-1 through A-13, Logs of Boring and Test Pits, in Appendix A Field Exploration. Typical grain size distribution curve for the site soils are shown Drawing No. B-1, Gradation Curves, in Appendix B, Laboratory Testing. Typical moisture density relationships for the site soils is presented in Drawing No. B- 2, Compaction Test, in Appendix B, Laboratory Testing. The laboratory maximum dry density and optimum moisture content of the samples tested ranged from 1 24 pounds-per-cubic foot (pcf) to 128.5 pcf and 10.0 percent to 12.0 percent, respectively. Results of consolidation tests performed to evaluate the compression characteristics of the site soils are presented in Drawings No. B-3 and B-4, Consolidation Test, in Appendix B, Laboratory Testing. Results of direct shear tests performed on relatively undisturbed ring samples are presented in Drawing Nos. B-5 and B-6, Direct Shear Test, included in Appendix B, Laboratory Testing. 5.5 Collapse/Expansion Potential In addition to consolidation tests, four (4) collapse tests were conducted on relatively undisturbed ring samples of near surface soils to evaluate collapse potential of the site soils. Based on the consolidation and collapsed tests performed on undisturbed samples, when inundated with water under a 2.0 kips per square-foot (ksf) normal load, samples collapsed from negligible to 2.0 percent. This range of results show that the site soils have negligible to moderate collapse potential. Expansion test of (1) representative site sample exhibited very low expansive potential. 5.6 Soil Corrosivity Two (2) representative samples of the site soils were tested to determine minimum electrical resistivity, pH, and soluble sulfate and chloride content. Results of these ~ ~ Converse Consultants CCIENTlOFFICEIJOBFILEI 1999181 199-305199-305-1-.gir \"? I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 7 tests are included in Appendix B, Laboratory Testing. The measured soil resistivity ranged from 3,800 to 35,000 ohm-cm at field moisture conditions. When saturated, the resistivity dropped to a range from 860 to 3,550 ohm-cm. This range of resistivity corresponds to moderately corrosive to severely corrosive to soils with respect to ferrous metals. Soil pH was found to range from 7.2 to 7.3. This value of pH corresponds to slightly alkaline and is not significant in evaluating soil corrosivity, Sulfate was not detected in the samples tested. The chloride content of the samples tested ranged from 18 parts-per-million (ppm) to 170 ppm. This range of sulfate content indicates the site soils have a negligible amount of sulfate exposure as per UBC (1997) Table No. 19-A-4, Requirements for Concrete Exposed to Sulfate Containing Solution. The table is given as in Table No.1, Requirements for Concrete Exposed to Sulfate-Containing Solutions. These results indicate that the site soils are, in general, not deleterious to concrete structures and are moderately to severely corrosive to ferrous metal. Type I or II Portland Cement may be used in concrete construction. For corrosion protection recommendations for underground utilities and other buried structures made of ferrous metal, we recommend that a corrosion specialist be contacted. Table No.1, Requirements for Concrete Exposed to Sulfate-Containing Solutions Maximum Water- Water-Soluble - Cementitious Sulfate ISO.) Materials Ratio, by Minimum f'c' Sulfate Cement Normal-Weight and Exposure in Soil, Sulfate (SO.) Type Weight, Normal- Lightwei9ht Ag9re9ate Percentage by in Water (ppm) Weight Aggregate Weight Concrete 1 Concrete (psi) Ne91igible 0.00-0.10 0-150 -- -- -- Moderate2 0.10-0.20 150-1,500 II. IP IMSI, 0.50 4,000 IS (MSI Severe 0.20-2.00 1,500-10,000 V 0.45 4,500 Very severe Over 2.00 Over 10,000 V plus 0.45 4,500 pozzolan3 1 A lower water-cementitious materials ratio or higher strength may be required for low permeability or for protection against corrosion of embedded items or freezing and thawing (Table 19-A-2 of use, 1997, Volume 2). 'Seawater. 'Pozzollan that has been determined by test or service record to improve sulfate resistance when used in concrete containing Type V cement. lb>- ~ Converse Consultants CCIENT\OFFICEIJOBFILEI 1999181 199-305199-305-1-.gir '^ I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 8 5. 7 Shrinkage and Subsidence Based on in situ density and compaction test results, shrinkage and subsidence were estimated as follows: . Alluvium Deposits: Alluvium are expected to shrink on an average of approximately 12% by volume, with variations from 6% to 14% shrinkage by volume. . Pauba (Bedrock): Shallow porous Pauba bedrock and deeper deposits may shrink from negligible to 10% by volume when properly recompacted, We recommend that an average shrinkage of 7% by volume may be used to estimate shrinkage for the Pauba bedrock. . Documented and Undocumented Fill: Shrinkage of documented fill may be neglected. Shrinkage of undocumented fill may be taken as 15% to 20%. . Subsidence: For estimation purposes, ground subsidence may be taken as 0.20 feet. These estimates are based upon the assumption that all removal and compaction is performed as recommended herein. 5.8 Groundwater Groundwater was not encountered in any of our borings or test pits to a maximum explored depth of 51.5 feet. Available well data from the general area of the proposed site indicates that depth to groundwater is greater than 150 feet (Cooperative Well Measuring Program, Spring 1999). 5.9 Slope Stability Slope stability was evaluated using the 1996 version of the computer program PCST ABL developed at Purdue University. The simplified Bishop method with circular failure surfaces was selected for the analyses. Surficial slope stability analyses were also performed using the method proposed by Duncan & Buchignani. Results of these analyses are presented in the sections below. A pseudo static analysis of slopes was conducted using a ground acceleration of 0.15g. For results of our analysis, see Appendix D, Slope Stability Analyses. ~ W Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81 \99-305\99-305-1-.9Ir \-5 I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 9 5.10 Subsurface Variations Based on the results of our subsurface exploration and experience, variations in the continuity and depth of subsoil and bedrock deposits should be anticipated. Due to uncertainty involved in the nature and depositional characteristics of the earth materials, care should be exercised in interpolating or extrapolating subsurface conditions between or beyond borings and test pits. Variations in groundwater levels should be expected due to seasonal changes, or artificial changes such as variable regional irrigation and changes in groundwater pumping. 6.0 FAULTING AND SEISMICITY 6. 1 Faulting Based on our review of the existing information, there are no known active faults projecting toward or extending across the proposed project site. An active fault is defined as one that has had surface displacement within Holocene time (about the last 11,000 years). The project site is not located within a currently designated State of California Earthquake Fault Zone. The nearest known active fault is the Wildomar (Temecula) Branch of the Elsinore Fault Zone, which is located approximately three (3) miles southwest of this site. The Murrieta Hot Springs Fault Zone is locate about three (3) miles north of the site. The State of California or the County of Riverside does not currently classify the Murrieta Hot Springs Fault as active. Recent studies performed on the Murrieta Hot Springs Fault indicate that the fault is active (personal communications, Dr. Tom Rockwell). However, the State of California and the County of Riverside have both conducted preliminary reviews of the study reports but neither agency has yet upgraded the fault designation from potentially active to active (personal communication, Mr. Steven Kupferman) . Converse conducted a fault study (Converse, 1989) to evaluate three photolineaments (possible faults) to evaluate the potential for site surface rupture. The fault study consisted of the excavation of five (5) trenches across the previously identified photolineaments. Converse Consultants, Dr. Roy Shlemon (Quaternary faulting consultant) and Mr. Steven Kupferman (Riverside County Geologist) observed the fault trenches. Based on the observations and results of the fault study, the photolineaments were interpreted to be the result of normal weathering processes and are not due to surface fault rupture. Major local and regional faults within 100 km (62 miles) from the project site are considered in this evaluation. Table No.1, Seismic Characteristics of Regional Faults, presents approximate distances from the site and other important seismic characteristics of the various faults. A fault map depicting the approximate location ~ ~ Converse Consultants CCIENTlOFFICEIJOBFILEI 1999181 199-305199-305-1-.gir \~ I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 10 of the site and the locations of the various regional active faults is shown in Figure No.2, Fault Map. Of those listed in Table No.2, Seismic Characteristics of Nearby Fau/ts, the Wildomar (Temecula) Fault of the Elsinore Fault Zone is considered the most capable of generating significant ground motions at the project site. Historical seismic events within a 100km (62 miles) radius of the site are shown in Figure No.3, Earthquake Epicenter Map. 6.2 Seismicity The project site is situated in a seismically active region. As is the case for most areas of southern California, ground shaking resulting from earthquakes associated with nearby and distant faults may occur. During the life of the project, seismic activity associated with active faults in the area may generate moderate to strong ground shaking at the site. According to the Uniform Building Code (1997), the project site is situated in Seismic Zone 4. Major damage corresponding to intensities VIII or higher on the Modified Mercalli Intensity Scale may occur within this zone. Seismic Zone 4 also includes those areas that lie within a zone of major (Richter Magnitude, M > 7) historic earthquakes and recent high levels of seismicity. A Maximum Credible Earthquake (MCE) is defined as the maximum seismic event that a particular fault is theoretically capable of producing and is evaluated based upon existing geologic and seismologic evidence. A deterministic analysis was performed by utilizing the computer program EQFAUL T developed by Blake (1997) to evaluate MCE and associated seismic parameters for various active faults within 100 km (62 miles) of the site. The faults in Table No.2, Seismic Characteristics of Regional Faults, are those most likely to generate ground acceleration (> 0.1 Og) at the site in case of a major earthquake. The results of the analysis are presented in Table No.2, Seismic Characteristics of Nearby Faults. Only those active or potentially active faults that are estimated to be capable of generating a ground acceleration of 0.1 g or greater at the project site are included in Table No.2, Seismic Characteristics of Nearby Active Fau/ts. The peak horizontal site accelerations presented in Table No.2, Seismic Characteristics of Nearby Active Faults, are obtained in accordance with the "Random-Mean + 1 x Standard Deviation" attenuation relationship (Boore, et. aI., 1993 with CDMG fault model). The soils profile is classified as a Type B: soft rock/stiff soil sites for purpose of this analysis. ~ ~ Converse Consultants CCIENTlOFFICEIJOBFILEI 1999181 199-305199-305-1-.glr \'\ ~ )> ,- '1 o ;:0 z - )> ~ ~ ; r- 0/ o V1 )> Z C) '" r V1 /'d[;i i/ ,c; g '" C) o o u )> o '1 () o o rrl )> Z L o CD Z o <!J <!J I OJ I '^ o N I o I U1 --4 o :;0 o }> ,- 1'1 }> :;0 --4 I o C }> ^ f"Tl U1 CO o o --4 o ~ <.0 <.0 <.0 Z I> 0 ~V1 '" ("") V1 ~ )> 0 CD r- ~'" 0 0 '" X "U r- )> Z !'; o z , I> G GG '" '" '" '" '" II II II II II -Po V1 en -..J OJ 0 0 0 0 0 I I I I -Po V1 en 'oJ + <0 <0 '" '" V1 ~ '" r- o ("") )> --; 6 z ~ + ~ r- r- oo ,,- <..Q::+: -.e eeL eL" " I I '-' -'-' -u, -..J-Po _-Po <.n'" N NZ '" m > ;::0 -f :I: o C > " m m "tJ - (") m z -f- m ;::0 s: )> "tJ -"0-0 Q ~.:IJ ..< 0 rO-O co-o ::>-;en ::>com ~30 I~:I:l oem 3-en '" - ,,' <:> '"Om '" Z =:-; o;r> 3 r w.o m < m r o -0 s: m Z .-; -; m Z -; l> -; <: m -; :IJ l> o -; N '" N co '" \)\ ~~ n o ~ < CD ""I CII CD n o ~ CII c: - Ql ~ - CII -0 o roO o ~ Z o c.o c.o , CO ..... , W o CJ1 , o ..... -" <D. c CD Z o w I I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 11 Table No.2, Seismic Characteristics of Regional Faults .? '. --c- APPROX. ASSIGNED MAXIMUM PEAK FAULT DISTANCE TO MAXIMUM HORIZONTAL NAME FAULT CREDIBLE GROUND FROM PROJECT EARTHQUAKE ACCELERATION AT '. SITE MAGNITUDE PROJECT SITE .'mile51 M' Inl ELSINORE-WILDOMAR (TEMECULA) 3 6.8 0.586 ELSINORE-JULIAN 14 7.1 0.275 ELSINORE-GLEN IVY - 13 - 6.8 0.247 SAN JACINTO-ANZA 19 7.2 0.231 SAN JACINTO-SAN JACINTO VA 19 6.9 0.197 SAN ANDREAS - Southern 36 7.4 0.159 ELYSIAN PARK THRUST 49 6.7 0.158 COMPTON THRUST 53 6.8 0.156 SAN ANDREAS - SAN BERNARDINO 36 7.3 0.151 CHINO-CENTRAL AVE. (Elsinore) 31 6.7 0.150 NEWPORT-INGLEWOOD (Offshore) 30 6.9 0.141 SAN ANDREAS - 1857 RUPTURE 57 7.8 0.137 ROSE CANYON 33 6.9 0.131 CORONADO BANK 47 7.4 0.130 CUCAMONGA 47 7.0 0.127 WHITTIER 35 6.8 0.118 SAN JACINTO-SAN BERNARDINO 33 6.7 0.117 SIERRA MADRE 52 7.0 0.117 NORTH FRONTAL FAULT ZONE 53 7.0 0.116 PINTO MOUNTAIN 43 7.0 0.112 SAN JACINTO-COYOTE CREEK 38 6.8 0.111 PALOS VERDES 49 7.1 0.107 NEWPORT-INGLEWOOD (L.A. Basin) 45 6.9 0.103 LANDERS 60 7.3 0.101 Moment Magnitude Mw of earthquake expected for rupture of entire fault length, estimated with slip-rate dependent empirical relations between seismic moment Mo and fault length and assuming the empirical relationship Log Mo=1.5 Mw + 16.1 (Hanks and Kanamori, 1979 ). Based on the results of the above deterministic analysis, the project site may experience a peak horizontal ground acceleration on the order of 0.59g, where g is the acceleration due to gravity due to the movement on the Wildomar (Temecula) branch of the Elsinore Fault Zone. The vertical acceleration may be taken as two- thirds of the horizontal acceleration. ~ ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81 \99-305\99-305-1-.gir 7P I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 1 2 6.2.1 Historical Data Analysis A search was also performed utilizing the computer program EQSEARCH by Blake (1998) to find the historical seismic events within a 100-km (62-mile) radius of the site. The results of the search indicate that the project site might have experienced a peak horizontal ground acceleration of 0.252g in 1918 due to an earthquake of moment magnitude 6.8 associated with the nearby San Jacinto Fault Zone. The peak acceleration was determined in accordance with the "Random-Mean + one x standard deviation" attenuation relationship by Boore et al (1993) corresponding to "Soil Type B." 6.3 Liquefaction Evaluation Soil liquefaction occurs in submerged granular soils during or after strong ground shaking. There are several requirements for liquefaction to occur. They are as follows: . Soils must be submerged · Soils must be primarily granular · Soils must be contractive, that is, loose to medium-dense · Ground motion must be intense · Duration of shaking must be sufficient for the soils to lose shearing resistance Due to the absence of shallow water table and due to the fact that site soils are primarily fine grained, the site soils are not considered susceptible to liquefaction. 6.4 Secondary Hazards due to Seismic Activity Secondary hazards from seismic activity include ground surface rupture, ground lurching, landsliding, earthquake-induced flooding, seiches, and tsunamis. The site- specific potential for each of these seismic hazards is discussed in the following sections. Surface Fault Rupture: The site is not located within a currently designated State of California Earthquake Fault Zone. Based on review of existing geologic information, no major surface fault crosses through or projects towards the site. The potential for surface rupture resulting from the movement of the nearby major faults is not known with certainty but is considered low. Lateral Spreading: Soils on fill slopes are prone to lateral spreading during earthquakes. To reduce the potential of lateral spreading, laterally unrestrained fill should be keyed and/or buttressed and keyed into native soils as recommended in ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.9ir -z.,\ I I I I I i I I I I I I I I I I I I I I 99-81-305-01 January 20. 2000 Page 1 3 Appendix C, Recommended Earthwork Specifications. The potential for lateral spreading at the site is considered low. Landslides: Seismically induced landslides and other slope failures are common occurrences during or soon after earthquakes. The potential for seismically induced landslides to affect the project site once it has been graded is considered very low. Tsunamis: Tsunamis are tidal waves generated by fault displacement or major ground movement. Based on the location of the site, tsunamis do not pose a hazard to this site. Seiches: Seiches are large waves generated in enclosed bodies of water in response to ground shaking. Based on the location of the site, seiches do not pose a hazard to this site. Earthquake-Induced Flooding: This is flooding caused by the failure of dams or other water-retaining structures as a result of earthquakes. Based on the location of the site, earthquake-induced flooding is considered to be low. 7.0 CONCLUSIONS The following conclusions are based on the results of our field exploration, laboratory testing and analysis/interpretation of the data as presented in the preceding sections. · The subject site is suitable, from a geotechnical standpoint for the construction of the proposed residential development provided the recommendations presented in this report and subsequent reports are considered in the planning, design and construction. · The site is not located within a currently designated State of. California Earthquake Fault Zone. The nearest known active fault designated as the State of California Earthquake Fault Zone and capable of generating significant ground motion at the site is the Elsinore-Wildomar (Temecula) Fault. This is located approximately three (3) mile southwest of this site. · The Elsinore-Wildomar (Temecula) Fault is considered to have the greatest potential to have an impact at the project site. Based on a deterministic seismic hazard analysis, the project site may experience a mean peak horizontal ground acceleration on the order of 0.59g, where g is the acceleration due to gravity, due to a maximum credible earthquake of moment magnitude of 6.8 associated with the Elsinore Fault. · The project site is not susceptible to soil liquefaction during earthquakes. ~ ~ Converse Consultants CCIENT\OFFICEIJOBFILEI1999181199-305199-305-1-.9ir '?Jt'" , I I ! I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 1 4 · The potential of seismic hazards due to the secondary effects of earthquakes including seismically induced ground settlement and differential settlement, lateral spreading, landslides, earthquake induced flooding is considered to be very low to low. Based on the site location, tsunamis or seiches do not pose a hazard. · Groundwater was not encountered in the exploratory borings drilled to a maximum depth of 51.5 feet below existing ground surface. Based on available information; the depth to groundwater within the general vicinity of the project site is deeper than 150 feet below existing ground surface. · The site soils encountered at the project site exhibited negligible to moderate collapse potential. · Site soils have very low expansion potential. · Site soils are moderately corrosive to severely corrosive to ferrous metal and are generally not deleterious to deleterious to concrete structures. Type I or II Portland Cement may be used for concrete construction. · Site grading, in general, should include removal and replacement as processed compacted fills for the upper three (3) to five (5) feet of disturbed alluvial deposits and undocumented artificial fill soils. · Deeper removal may be required along some localized areas. · Earth materials at the site should be excavatable with conventional earth moving equipment. . The proposed fill/cut slopes with slopes 2: 1 (H:V) are grossly stable under static as well as earthquake loading conditions. · One- or two- story residential structures may be supported on conventional footing foundations. Concrete slabs-on-grade for such buildings may be of the conventional type as opposed to grade-beam or post-tensioned types, 8.0 EARTHWORK/SITE GRADING RECOMMENDATIONS 8. 1 General This section contains our recommendations regarding earthwork and site grading for the proposed development of the site. These recommendations are based on the ~ ~ Converse Consultants CCIENTlOFFICEIJOBFILEI 1999181 199-305199-305-1-.9ir {,,/7 I I I . I . I .. I I I I I . I I I . I 99-81-305-01 January 20, 2000 Page 1 5 results of our field exploration, laboratory testing and data/evaluation as presented in the preceding sections. Loosely backfilled exploratory test pits located throughout the site, and any existing undocumented fill below proposed structures, will require overexcavation and recompaction prior to the placement of structural fill. See Drawing No.1, Approximate Boring and Test Pit Location Map for approximate locations of test pits. All fills should be placed in accordance with the recommendations presented in Appendix C, Recommended Earthwork Specifications. All fills should be properly benched into firm and unyielding-native materials. 8.2 Rem 0 val/Overexca vation All surface trash and vegetation (including, but not limited to, heavy weed growth, trees, stumps, logs, and roots) should be removed from the areas to be graded. Organic materials resulting from the clearing and grubbing operations should be hauled off the site. Existing underground storm drain pipe should be abandoned in place. In general, approximately the upper three (3) to five (5) feet of disturbed alluvial deposits and all undocumented fill soils are not suitable for supporting structures or structural fills. Fill thicknesses are anticipated to range from approximately 2 to 5 feet. Site grading should include removal and recompaction of these unsuitable soils. During grading, if rocks larger than 6 inches in dimension are encountered and/or are protruding above the bottom of the excavation, they should be removed completely and the voids should be filled with compacted backfill. All loose and fill soils should be removed to firm and unyielding soil. Actual removal depth at the site should be based on observation of the conditions encountered during grading. At least the upper six inches of all excavated surfaces should be scarified and moisture conditioned, if necessary, and compacted to at least 90 percent relative compaction as per ASTM Standard 01557-91 prior to placing any fill and/or structures. All exploratory test pits were loosely backfilled and will require overexcavation and recompaction for support of new improvements. A Converse representative must observe the bottom of the excavated areas prior to placement of new fill. Soils removed during the overexcavation procedures may be utilized as compacted fill, provided they have been stripped of organic and other deleterious materials. All proposed fills should be placed on competent native materials as determined by a Converse representative and in accordance with the specifications presented in Appendix C, Recommended Earthwork Specifications. ~ ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81\99-305\99-305-1-.gir V\. II ,I I I I I I I II I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 1 6 8.3 Temporary Sloped Excavations Temporary sloped excavations may be feasible where plan dimensions for excavations are not constrained by site boundaries, existing streets, or other structures. Where constraints exist, shoring, or a combination of slopes and shoring, will be required. Sloped temporary excavation within the site may be cut according to the slope ratios presented in Table No.3, Temporary Excavation Slopes. Table No.3, Temoorarv Excavation Slones . MAXIMUM DEPTH OF CUT (feet) MAXIMUM SLOPE RATlO* (Horizontal:Verticall 0-5 Vertical 5-10 0.5:1 10-20 1:1 'Selection of temporary slope ratios should be made by the grading contractor based on actual materials encountered during excavation. It is the responsibilily of the contractor to evaluate stability conditions and maintain safe conditions during cutting. Slope ratios given above are assumed to be uniform from top to toe of the slope. Sandy surfaces exposed in sloped excavations should be kept moist but not saturated to retard raveling and sloughing during construction. Adequate provisions should be made to protect the slopes from erosion during periods of rainfall. Surcharge loads should not be permitted within 10 feet or a distance of at least half the slope height from the top of slope, whichever is greater. 8.4 Site Drainage Adequate positive drainage should be provided away from building pad areas to prevent ponding and to reduce percolation of water into the foundation soils. Building pads should have a drainage gradient of at least two (2.0) percent towards drainage facilities. Planters and landscaped areas adjacent to the building pad perimeter should be designed and irrigated to minimize water infiltration into the subgrade soils. The majority of the Pauba Formation contains appreciable amounts of fines and is not considered free draining. Drainage gradient lower than two (2) percent and/or excessive irrigation of planters and landscaped areas can result in overly saturated conditions and/or perched groundwater conditions at shallow depths within the building pad areas, street and sidewalk subgrades. Irrigation waters, if excessive, will percolate to subsurface soils. Such subsurface water will flow from raised-grade pads to adjacent lower-grade pads. Such subsurface flow will supplement the percolating subsurface water resulting from the irrigation of the lower pads themselves and can result in overly saturated and/or ~ W Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.9ir z6 I I I I I I I II I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 1 7 perched groundwater conditions. Irrigation should be maintained such that it does not result in excess groundwater or slopes adjacent to raised pads should be provided with sub-drain along the toe to intercept subsurface water flow. Surface drainage should preclude the possibility of flow over slope faces, with the use of brow ditches, earth berms and other methods. Adequate drainage should also be provided for the cut/fill slopes, landscaped areas . outside building pads, such as parks and recreation areas, and paved areas. A desirable drainage gradient is one (1) percent for paved areas and two (2) percent in the landscaped area. Surface drainage should be directed to suitable non-erosive devices. Slope drainage should be constructed in accordance with Appendix Chapter 33 of the Uniform Building Code (1997). 8.5 Slope Protection and Maintenance Slopes should be planted as soon as possible after construction. Slopes will require maintenance through time to perform in a satisfactory manner. In most cases, lot and site maintenance can be provided along with normal care of the grounds and landscaping. The cost of maintenance is less expensive than repair resulting from neglect. Most hillside lot problems are associated with water. Uncontrolled water from a broken pipe, excess landscape watering, or exceptionally wet weather cause most . damage. Drainage and erosion control are important aspects of slope stability, and the provisions incorporated into the graded site must not be altered without competent professional advice. Terrace drains and brow ditches on the slopes should be periodically maintained and kept clear so that water will not overflow onto the slope, causing erosion. Landscaping on the slopes should disturb the soil as little as possible and utilize drought-resistant plants that require a minimum amount of landscape irrigation. Wet spots on or around the site should be noted and brought to the attention of Converse or an experienced geotechnical engineer. These may be natural seeps or an indication of broken water or sewer lines. Watering should be limited or stopped altogether during the rainy season when little irrigation is required. Over-saturation of the ground can cause subsidence within subsurface soils. Slopes should not be over-irrigated. Ground cover and other vegetation will require moisture during the hot summer months, but during the wet season, irrigation can cause ground cover to pull loose. This not only destroys the @ ~ Converse Consultants CCIENTlOFFICEIJOBFILE\ 1999\81 \99-305\99-305-1-.glr 7)q I II I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 18 cover, but also starts serious erosion. It is suggested to consult a professional landscape architect for planting and irrigation recommendations. 9.0 STRUCTURAL DESIGN RECOMMENDATION SECTION 9. 1 Foundation Design Parameters For preliminary design purposes, conventional spread footings founded on properly compacted structural fill or approved native soils may be used to support single-story structures. Footings should be set back as recommended in Figure 18-1-1 of theUBC (1997). Width of the footings for one-story and two-story buildings should be at least 12 inches and 18 inches, respectively. Interior and exterior footings should be placed at least 12 inches and 18 inches, respectively, below lowest adjacent soil grade. Footings for one- and two- story wood-frame structures may be designed for an allowable bearing pressure of 2,000 pounds per square foot (psf). All continuous footings should be reinforced with at least #4 reinforcing bars top and bottom, along the full width of the footings, to mitigate the potential for differential fill settlement. The project structural engineer may require additional reinforcement. Structures set back must satisfy the requirements of Figure 18-1-1 of the UBC (1997). Conventional spread footings founded in properly compacted structural fill or approved native soils may be used to support the proposed buildings. 9.2 Lateral Earth Pressure Cantilevered earth retaining walls should be designed based on an active earth pressure equal to that developed by a fluid of density of 40 pounds per cubic foot (pcf). These pressures assume a level ground surface behind the wall for a distance greater than the wall height. If water pressure is allowed to build up behind the walls, the active pressures should be reduced by 50 percent and added to a full hydrostatic pressure to compute the design pressures against the wall. At-rest earth pressure equal to that developed by a fluid of density of 60 pcf. 9.3 Lateral Resistance Resistance to lateral loads can be assumed to be provided by friction acting at the base of foundations and by passive earth pressure. A coefficient of friction of 0.40 between concrete and soil may be used with the dead load forces. Passive earth. pressure of 300 psf per foot of depth may be used for the sides of footings poured against recompacted native soil. The maximum value of the passive earth pressure should be limited to 2,000 pst. If the coefficient of friction and the passive pressures are used in combination, the coefficient of friction should be reduced by 50 percent. These lateral resistances may be increased by 33 percent for seismic forces. a>- ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.gir '7,;'\ I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 19 The recommended design parameters are provided for preliminary estimates only. The final bearing pressures and lateral resistances should be provided at the completion of grading. Such recommendations would be based on testing and evaluation of the soil conditions under the proposed foundation levels after the completion of rough grading. Vertical and lateral bearing values indicated above are for the total dead load and frequently applied live loads. If normal code requirements are applied for design, the above vertical bearing and lateral resistance values may be increased by 33% for short duration loading, which will include the effect of wind or-seismic forces. 9.4 Settlement Structure settlement will be due to relatively light foundation loads, as well as long- term compression of fill soils and compressible native materials below the fill. Compacted fill will settle, depending on the fill thickness and future changes in the "as-compacted" moisture conditions. To minimize settlement due to wetting, fill should be compacted within 3 percent of optimum. To minimize differential settlement, variations in the fill thickness, soil types and relative compaction, to the extent possible, should be kept to a minimum. Anticipated total settlements of continuous footing, designed as recommended above, from structural load-induced settlements and short-term settlement of properly compacted fill is 1.0 inches or less. The expected differential settlement can be taken as equal to half of the total settlement. 9.5 Slabs-an-Grade The design of the slab-on-grade, among other factors, will depend on the expansive potential of the pad soils. Based on the Expansion Index tests performed during this investigation, the expansion potential of the site soils should be very low. The slabs- on-grade for building pads with very low Expansion Index (< 20) may be of the conventional type as opposed to post-tensioned. The UBC (1997) recommends post- tensioned slabs for lots with expansion index greater than 20. Specific recommendations regarding the type of slab-on-grade should be based on testing of the Expansion Index of the pad subgrade soils at the completion of grading. The slabs-on-grade should be at least four (4) inches thick. Care should be taken to avoid slab curling if slabs are poured in hot weather. Conventional slabs-on-grade should be provided with a 6"x6"-#1 0/#1 0 reinforcement or as recommended by the structural engineer. Slabs-on-grade should be protected by 6-mil-thick polyethylene vapor barriers. The barrier should be underlain and overlain by two inches and one inch of sand, respectively, to minimize punctures and to aid in the concrete curing. ~ ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81 \99-305\99-305-1-.gir Vb II I II I I ! I ! I II ! I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 20 Subgrade for slabs-on-grade should be firm and uniform. All slab subgrades should be moisture-conditioned to within three (3) percent of optimum prior to the placement of concrete. All loose or disturbed soils including under slab utility trench backfills should be recompacted prior to the placement of clean sand underneath the moisture barrier. In accordance with UBC (1997). the geologic subgrade classification for the site will be SD in accordance with Table 16-J. The site coefficients at the site will be: Ca=0.46, Cv=0.80, Na= 1.0; Nv= 1.3, Ts=0.700 To =0.140 10.0 BURIED UTILITY, PAVEMENT AND CONSTRUCTION RECOMMENDATIONS 10. 1 Buried Utility Trench Backfill 10.1.1 General Buried utility construction will involve open-cut trench excavation, pipe subgrade preparation, and placement of bedding, if used, before placing the pipe. The trench will then be backfilled with compacted fill to final grade. The backfill material for the pipe zone should be selected by the pipe designer. The pipe zone is defined as the portion of the trench section extending from the pipe invert to one foot above the top of the pipe. The remainder of the trench section above the pipe zone is defined as the trench zone. Where the conduit underlies pavement, the trench backfill should be placed and compacted in accordance with Appendix C, Recommended Earthwork Specifications. Excavated on-site soils free of organic matter may be used to backfill the trench zone. Imported trench backfill should be approved by Converse prior to delivery. 10.1.2 Pipe Bedding Bedding is defined as the material supporting, surrounding and extending to 12 inches above the top of the pipe. To provide uniform and firm support for the pipeline, free-draining granular soil should be used as pipe bedding material. For flexible pipes, sand or excavated materials may be used as bedding materials. Crushed rock or gravel may be used for rigid pipes. The thickness of the bedding material under the pipe, if any, should be selected by the pipeline design engineer. ~ ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81 \99-305\99-305-1-.glr 1.A I I I I :I I i I ,I ! I 'I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 21 Migration of fines from the surrounding native and/or fill soils must be considered in selecting the gradation of the imported bedding materials. Imported bedding materials should contain materials at least 1 5 percent finer than the size corresponding to 85 percent passing by weight of the surrounding native or fill materials. Specific gradation requirement for the bedding should be provided by Converse or a qualified geotechnical engineer at the end of grading by performing gradation analysis of the soils within the pipe depth. Prior to placing the bedding materials, the trench excavation should be cleared of soft or disturbed materials. Bedding materials should be placed on firm and unyielding subgrade soils. Where the bottom of the excavation is soft, the foundation soils should be removed to expose firm materials as determined by the project's soils consultant based on field observation. Bedding materials should be placed to a minimum of 12 inches above the top of the pipe or as required by the pipe design engineer. Bedding materials should be vibrated in-place, and care should be taken to densify the bedding material below the spring line of the pipe. Flooding or jetting of the bedding materials should not be attempted because the water from the trench is not expected to drain freely. Long-term accumulation of water in the pipe trench from any sources should be avoided, and trenches should be pumped dry if water collects inside. 10.2 Asphalt Pavement One representative sample of the site soils was tested to evaluate the resistance (R)- value in accordance with the State of California Test Method 30 1-G. The results are presented in Appendix B, Laboratory Testing. An analysis was performed in accordance with the method suggested in the Caltrans Highway Design Manual to determine required flexible pavement structural sections for a range of Traffic Indices (TI) and an R-value of 22. Results of this analysis are presented in Table No.4, Recommended Preliminary Structural Sections for Flexible Pavement. These preliminary sections are provided for planning purposes only. Final pavement structural sections should be provided by Converse based on the R-value of the actual soil conditions after grading and the design TI for each street. Table No.4, Recommended Preliminary Structural Sections for Flexible Pavement o . R I 22 eSIQn -va ue = STRUCTURAL SECTIONS Traffic Index (TI) Asphalt Concrete (AC) Aggregate Base (AB) (inches) (inches) 5 or below 3.0 7.5 5.5 and 6.0 3.0 10.5 6.5 and 7.0 3.0 14.0 ~ ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81\99-305\99-305-1-.9ir ?/Y I I I I I I I I I I I I II I I I I I I I I 99-81-305-01 January 20, 2000 Page 22 In areas to support asphalt pavement, the subgrade should be recompacted to a depth of at least one foot below the final subgrade prior to paving, as recommended in Appendix C, Recommended Earthwork Specifications. At the time of placing pavement, the subgrade should be firm and unyielding during proof rolling, and should be within 3 percent of optimum moisture. All base material should be compacted to a minimum of 95% of the (ASTM Standard D1557-91) laboratory maximum dry density. Base material should consist of Caltrans Class 2 Aggregate Base (Caltrans Standard Specification 26-1.02B) or should- conform with Section 200-2.2; "Crushed Aggregate Base," and should be placed in accordance with Section 301-2, "Untreated Base," of the SSPWC. Asphaltic materials should conform with Section 203-1, "Paving Asphalt," of the SSPWC and should be placed in accordance with Section 302-5, "Asphalt Concrete Pavement," of the SSPWC. The street pavement structures and sidewalks should be provided with adequate surface and subsurface drainage. 11.0 GEOTECHNICAL SERVICES DURING CONSTRUCTION This report has been prepared to aid in the evaluation of the site, to prepare site- grading recommendations, and to assist the structural engineer in the preliminary design of the proposed structures. It is recommended that final design drawings and specifications be reviewed by the project's geotechnical consultant to evaluate if the recommendations of this report have been properly implemented. Recommendations presented herein are based upon the assumptions that continuous earthwork monitoring will be provided by Converse. Removal of excavation bottoms should be observed by a Converse representative. Structural fill and backfill should be placed and compacted during continuous observation and testing by this office. Footing excavations should be observed by Converse prior to placement of steel and concrete, so that footings are founded on satisfactory materials and excavations are free of loose and disturbed materials. 12.0 CLOSURE The findings and recommendations of this report were prepared in accordance with generally accepted professional engineering and engineering geologic principles and practice at this time in Southern California. Our conclusions and recommendations are based on the results of the field and laboratory investigations, combined with an interpolation of subsurface conditions between and beyond exploration locations. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI1999181199-305199-305-1-.gir '7\ I I I !I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 23 As the project evolves, our continued consultation and construction monitoring should be considered an extension of geotechnical investigation services performed to date. Converse should review plans and specifications to ensure the recommendations presented herein have been appropriately interpreted, and that the design assumptions used in this study are valid. Where significant design changes occur, Converse may be required to augment or modify these recommendations. Subsurface conditions may differ in some locations from those encountered in the explorations, and may require additional analyses and/or modified recommendations. This report was written for Lennar Communities and only for the proposed development described herein. We are not responsible for technical interpretations made by others, or exploratory information that has not been described or documented in this report. Specific questions or interpretations concerning our findings and conclusions may require written clarification. ~ ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81 \99-305\99-305-1-.gir ~ I I I I I I I 'I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page 24 13.0 REFERENCES BLAKE T. (1998), EQFAUL T, Version 2.01, A Computer Program for the Deterministic Prediction of Peak Horizontal Acceleration from Digitized California Faults, Computer Services and Software, Newbury Park, California. BLAKE, T. (1998), FRISK89, A Computer Program for the Probabilistic Estimation of Seismic Hazard Using Faults as Earthquake Sources," 1995 ed., Computer Services and Software, Newbury Park, California. BOORE, D. M., JOYNER, W. B., and FUMAL, T. E, 1993, Estimation of Response Spectra and Peak Acceleration from Western North American Earthquakes, An Interim Report, U.S.G.S. Geological Survey Open-File Report 93-509, 15 pages. CALIFORNIA DEPARTMENT OF TRANSPORTATION, 1992, Highway Design Manual. CALIFORNIA DIVISION OF MINES AND GEOLOGY (1994). Map No.6 - Fau/t Activity Map of California and Adjacent Areas. Converse Consultants (1999). Summary of Geotechnical Conditions, Sweetwater Specific Plan, Approximately 560-Acre Site Temecula, California, Converse Project No. 98-81-104-01, Dated June 2'1,1999. Converse Consultants (1998). Summary of Geotechnical Conditions, Winchester Hills Residential Development, Temecula, California, Converse Project No. 98- 81-104-01, Dated February 20, 1998. Converse Consultants Inland Empire (1990), Geotechnical Investigation, Tentative Tracts 25321 Through 25324 and 25464, Winchester Hills Residential Development, Temecula, California, CCIE Project No. 89-81-173-01, Dated October, 8, 1990. KENNEDY, M. P., 1977; "Recency and Character of Faulting Along the Elsinore Fault Zone in Southern Riverside County, California," CDMG Special Report 131. STANDARD SPECIFICATIONS FOR PUBLIC WORKS CONSTRUCTION (1994), Building News, Inc., Los Angeles, California, UNIFORM BUILDING CODE (UBC). 1997, International Conference of Building Officials. WARING, G. A., 1919; "Groundwater in the San Jacinto and Temecula Basins, California," USGS Water Supply Paper 429. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.gir <J;'? I I II 'I II il I , I I I I , I I I I I I I I APPENDIX A FIELD EXPLORATION ?" I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page A-l APPENDIX A FIELD EXPLORATION Field exploration included a site reconnaissance and subsurface exploration program. During the site reconnaissance, the surface conditions were noted, and the locations of the test borings and test pits were established. Exploratory borings and test pits were approximately located using existing boundary and other features as a guide. (Drawing No.1, Approximate Boring and Test Pit Location Map). Exploratory borings were advanced using a six-inch-diameter hollow-stem auger drilling equipment. Ring samples of the subsurface materials were obtained at frequent intervals in the exploratory borings using a drive sampler (2.4-inch inside diameter, three-inch outside diameter) lined with sample rings. The steel ring sampler was driven into the bottom of the borehole with successive drops of a 140-pound driving weight falling 30 inches. Standard Penetration Tests (SPT) were also performed in the boring at frequent intervals in accordance with ASTM Standard D1586-84. The recorded blow counts after six inches of seating penetration are shown in the Logs of Boring in the "blows/foot" column. SPT samples were collected in plastic bags. Exploratory test pits were excavated by a backhoe equipped with a 24-inch-wide bucket. Ring samples of the subsurface materials were obtained at frequent intervals in the test pits using a hand drive sampler (2.4-inch inside diameter, three-inch outside diameter) lined with sample rings. The central portion of the ring samples were retained and carefully sealed in waterproof plastic containers for shipment to the Converse laboratory. Bulk samples of typical soil types were also obtained. Encountered earth materials were continuously logged by a Converse geologist and classified in the field by visual examination in accordance with the Unified Soil Classification System. Where appropriate, field descriptions and classifications have been modified to reflect laboratory test results. Logs of the exploratory borings are presented in Drawings No. A-l through A-5 and logs of the test pits are presented in Drawings No. A-6 through A-13. Boring and test pit summary sheets also include descriptions of the materials, pertinent field data and supplementary laboratory data. A key to soil symbols and terms is presented as Drawing No. A-14. ~ . ~ Converse Consultants CCIENTlOFFICEIJOBFILEI 1999181 199-305199-305-1-.gir ~ I I I I I I I I I I I I I I II I I I I log of Boring No. BH-1 Dates Drilled: 12/16/99 Logged by: CWK Equipment: Ground Surface Elevation(ft): 6" H.S.A. Driving Weight and Drop: 1116.5 Depth to Water(ft): Checked by: 140 lb / 30 inch None Encountered MOC SUMMARY OF SUBSURFACE CONDITIONS AMPLE f- t< f- This log is part of the report prepared by Converse for this project and should be 0 $ read together with the report. This sununary applies only at the location of the 0 w ~ U u.. cr: f- - boring and at the time of drilling. Subsurface conditions may differ at other ~ ~ Z I I locations and may change at this location with the passage of time. The data (J) f- ~ cr: a.. w $ w f- presented is a simplification of actual conditions encountered. > '" (J) a.. <(<.9 ....J 0 0 >--= I w cr:o cr: ~ ....J cr:u f- 0 <.9....J 0 en en :;;; oEe 0 Al.urVnIM <0.1)' SILTY SAND (8M): fine to medium grained with clay, trace mica, Drown. 5 CIA YEY SAND (SC): fine to medium grained, dark brown. 10 REDROCK. PAlTRA Fm (Qp)' SANDSfONE: medium to coarse grained, trace clay with mica, brown. 15 20 x x x x x x x x x x x x x x x x x x x x x x x x x x x x SILTSTONE: trace clay with mica, brown. 25 SILTY CLAYSTONE: trace coarse grained sand with mica, grayish brown to brown. 30 SILTY SANDSTONE: fme to medium grained, trace coarse, light brown. End of boring at 31.5 feet. Groundwater not encountered during drilling. Boring backfilled with soil cuttings on 12/16/99. @ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPME:->T 99-8t-305-01 TRACT 29286 City of Temecula 14 6 128 col 33 18 119 col 64 3 117 62 I 113 ma 12 39 14 10 44 31 74 c 49 24 Drawing No. A-I % I I I I I I I I I I I I I I I I I I I Log of Boring No. BH-2 Dates Drilled: 12/16/99 Logged by: CWK Checked by: 140 lb / 30 inch MOC Equipment: Ground Surface Elevation(ft): None Encountered 6" H.S.A. Driving Weight and Drop: Depth to Water(ti): SUMMARY OF SUBSURFACE CONDITIONS AMPLE f- ;J2. f- This log is part of the report prepared by Converse for this project and should be 0 S ~ read together with the report. This summary applies only at the location of the 0 LJ.J - U lJ.. a: f- boring and at the time of drilling. Subsurface conditions may differ at other ~ ::J Z I I locations and may change at this location with the passage of time. The dara (f) f- a: LJ.J ::J f- a.. presented is a simplification of actual conditions encountered. 2: ><: S (f) LJ.J a.. <t~ ...J 0 >-'" I LJ.J a:O a: ::J ...J 0 a: " f- 0 ~...J 0 OJ OJ ::2 0.9- 0 RFDRorK' PAlTRA Fm (Qp).: SILTY SANDSfONE: tine grained, trace coarse, slightly porous, brown. max,ca 50 3 113 ds 5 84 5 120 11 117 52 16 113 36 26 97 1143.5 10 - fme to coarse grained, trace clay 7 120 8 7 Drawing No. A-2 :?\ 15 SILTY CLAYSTONE: trace medium grained sand, brown. 20 SILTY SANDSTONE: fme grained with mica, brown. 25 2(11" 42 30 47 SANDSTONE: fme to coarse grained with mica, grayish white. End of boring at 31.5 feet. Groundwater not encountered during drilling. Boring backfilled with soil cuttings on 12/16/99. ~ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City of Temecula I I I I I I I I I I II I I I I I I I I Log of Boring No. BH-3 Dates Drilled: 12/16/99 Logged by: CWK Checked by: 140 lb / 30 inch MOC Equipment: Ground Surface Elevation(ft): 6" H.S.A. Driving Weight and Drop: 1135.0 Depth to Water(ft): None Encountered SUMMARY OF SUBSURFACE CONDITIONS AMPLE I- ~ ~ 0 This log is part of the report prepared by Converse for this project and should be 0 S - read together with the report. This sununary applies only at the location of the 0 w - U u.. ce I- boring and at the time of drilling. Subsurface conditions may differ at other - :J Z I I locations and may change at this location with the passage of time. The data if) l- ce w S :J I- a.. presented is a simplitication of actual conditions encountered. > '" if) w a.. <((9 -1 0 >-*" I w ceo ce :J -1 0 ce<.J I- 0 (9-1 0 m m ~ 0.3- 0 At t TJVITlM (Q;>l)- SILTY SAND (SM): fIne to medium grained, trace coarse, brown. 6 119 55 5 130 5 43 REnRorK- PAlmA Pm (Qp). SILTY SANDSTONE: fme to medium grained, brown. 10 40 29 98 ds CLAYSTONE: with mica, dark brown. max 15 x x x x ----------------------------------------------------------------- --------- 52 19 106 x " " x CLAYEY SILTSTONE: with flne to medium grained sand and mica, " " x x " " " " brown. x " x x x x x x x x x x x x x x x x x x x x x X X X X X X X X x 20 x x x x " x x x 29 12 x x x x x x x x x x x x x x x " x x x x x x x x X X X X X X X X - - -. - ~ ~ - - - - - - - - - - - - - - - - - - - - - - - - - - - -.. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 25 SILTY SANDSfONE: frne to medium grained with clay, brown 8 80 119 30 64 12 $ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City ofTemecula Drawing No. A-3a ~ I Log of Boring No. BH-3 Dates Drilled: 12/16/99 Logged by: CWK Checked by: 140 lb / 30 inch MOC I Equipment: Ground Surface Elevation(ft): 6" H.S.A. I 1135.0 Driving Weight and Drop: Depth to Water(ft): None Encountered I SUMMARY OF SUBSURFACE CONDITIONS AMPlE' f- ~ ~ 0 This log is part of the report prepared by Converse for this project and should b~ 0 - S read together with the report. This summary applies only at the location of (he 0 LU f- - U LL cr: - - boring and at the time of drilling. Subsurface conditions may differ at ocher - ~ I (f) Z I locations and may change at this location with the passage of time. The data f- ~ cr: LU S LU f- a.. presented is a simplification of acn.ml conditions encountered. > '" (f) a.. <((Cl ...J 0 0 >-<;; I LU cr:o cr: ~ ...J cr:u f- 0 (Cl...J 0 CO CO ~ oEe 0 SANDSfONE: fIne to medium grained with mica, light grayish brown. 72 5 104 - 40 -----------------.-+------------------------- ------------------------------- -~ SILTY SANDSTONE: fIne to medium grained, trace coarse sand with mica, ~ 27 brown. 45 33 28 100 -----+-------------------++----------+---------------------- -- -------- CLA YSfONE: trace medium grained sand, light brown. 50 tx 14 End of boring at 51. 5 feet. Groundwater not encountered during drilling. Boring backfilled with soil cuttings on 12/16/99. 55 I- 60 I- 65 I I I I I I I I I I I I I I @ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-Dl TRACT 29286 City of Temecula Drawing No. A-3b I ~ I I I I I I I I I I I I I I I I I 30 I I I log of Boring No. BH-4 Dates Drilled: 12/16/99 Logged by: CWK Checked by: 140 Ib / 30 inch MOC Equipment: Ground Surface Elevation(ft): 6" H.S.A. Driving Weight and Drop: 1135.0 Depth to Water(ft): None Encountered SUMMARY OF SUBSURFACE CONDITIONS AMPLE f- '" f- 0 This log is part of the report prepared by Converse for this project and should be 0 S read together with the report. This sununary applies only at the location of the 0 w f- - U LL 0:: - boring and at the time of drilling. Subsurface conditions may differ at other ~ ::J Z I (f) I locations and may change at this location with the passage of time. The dara W S f- ::J 0:: f- "- presented is a simplification of actual conditions encountered. > ~ (f) W "- <(l'J -1 0 0 >-;::- I w 0::0 0:: ::J -1 0::'-' f- a l'J-1 a en en :;;; a~ 0 RFnROC;K. PAlJRA Pm (Qp)' CLAYEY SANDSTONE: fIne to medium grained, slightly porous. brown to ei yellowish brown. 9 122 5 ------------------------------------------------------------- 50 9 123 SILTY SANDSTONE: fIne to medium grained, slightly porous, brown. 10 - trace clay 15 SANDSTONE: fme grained, light gray. 34 8 128 ma 31 20 SILTY SANDsrONE: fme grained, trace coarse sand, brown. 70 11 122 End of boring at 21.5 feet. Groundwater not encountered during drilling. Boring backfilled with soil cuttings on 12/16/99. 25 ~ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-8t-305-01 TRACT 29286 City of Temecula Drawing No. A-4 AI) I I I I I I I I I I I I I I I I I I I Log of Boring No. BH-5 Dates Drilled: 12/16/99 Logged by: CWK Checked by: 140 lb / 30 inch MOC Equipment: Ground Surface Elevation(ft): Depth to Water(ftl: None Encountered SUMMARY OF SUBSURFACE CONDITIONS AMPLE f- ;R f- 0 This log is part of the report prepared by Converse for this project and should be 0 S - read together with the report. This sununary applies only at the location of the 0 u.J - U LL OC f- boring and at the time of drilling. Subsurface conditions may differ at other ~ ::J Z I (f) I locations and may change at this location with the passage of time. The data u.J S f- ::J OC f- "- presented is a simplification of actual conditions encountered. > "" (f) u.J "- <(l9 ....J 0 >--=- I u.J OCo a: ::J ....J 0 OCt) f- 0 19....J 0 '" '" 2 0.2- 0 AI IITVIIIM (Q;>I).: SILTY SAND (8M): fme -to medium grained, trace coarse sand, brown to light brown. 5 - trace clay, very dark brown. - increasing clay content 10 REnROCK. PAllRA Fm (Qp). SILTY SANDSTONE: fme to coarse grained, trace clay wich mica, brown. 15 SANDSTONE (SP): fme grained, trace silt, light brown. 6" H.S.A. Driving Weight and Drop: 18 5 102 col 15 12 124 c 1116.0 20 etA VSfONE: with fme grained sand and silt, brown. SILTY CLA YSfONE: trace gravel, mica, light brown. 25 30 SILTY SANDSTONE: fme to medium grained with mica and clay, brown. $ Converse Consultants 53 10 130 10 101 8 17 20 23 100 41 11 Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPlV1ENT 99-81-305-01 TRACT 29286 City ofTemecula Drawing No. A-Sa 1\.\ I Log of Boring No. BH-5 Dates Drilled: 12/16/99 Logged by: CWK Checked by: 140 Ib / 30 inch MOC I Equipment: Ground Surface Elevation(ft): 6" H.S.A. I 1116.0 Driving Weight and Drop: Depth to Water(ft): None Encountered I SUMMARY OF SUBSURFACE CONDITIONS AMPm f- '"' f- a This log is pare of the report prepared by Converse for this project and should be 0 - s - read together with the report. This summary applies only at the location of the 0 w f- - U u- 0: - boring and at the time of drilling. Subsurface conditions may differ at ocher ~ ::J Z I I locations and may change at this location with the passage of time. The data (f) f- ::J 0: W S f- "- presented is a simplification of actual conditions encountered. > >< (f) w "- <(<.9 -' 0 >--= I w 0:0 a: ::J -' 0 o:u f- a <.9-, 0 CIl CIl :2: 0.3- 0 ..:: SILTY SANDSTONE fIne to medium grained with mica and clay, brown. 79 9 121 "- - trace coarse sand, mica, grayish brown - ..:: 40 - interbeds of clayey silt R 38 14 r- ------------------- ----------------------------------------- ----._---------- I- 45 SILTY SANDSfONE: fme to medium grained, trace clay, trace coarse, brown. 63 11 115 .. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ~ - - - - - - - - - - - - - - - -- ----------------- SILTY SANDSfONE; fme to medium grained, while to light gray. I- 50 - D< 38 13 End of boring at 51.5 feet. Groundwater not encountered during drilling. Boring backfilled with soil cuttings on 12/t6/99. - 55 - - 60 65 I I I I I i I I I I I I I I I ~ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City oFTemecula Drawing No. A-Sb I A.-z,. I Dates Drilled: I Equipment: Ground Surface Elevation(ft): I I ~ u - I I f- 0.. 0.. <(l'J LU ceo 0 l'J....J I' .' 5 I I I I I 10 I 15 - I I Log of Test Pit No. TP-1 12/20/99 Logged by: CWK Checked by: N/A BACKHOE. 24" Wide Driving Weight and Drop: MOC 1130.0 None Encountered Depth to Water(ti): SUMMARY OF SUBSURFACE CONDITIONS This log is part of the report prepared by Converse for this project and should be read together with the report. This summary applies only at the location of the boring and at the time of drilling. Subsurface conditions may differ at other locations and may change at this location with the passage of time. The data presented is a.simplification of actual conditions encountered. ~AMPLES LU ~ ::: ce ::J o CO ARTIFJCTAT FlU. (At). SILTY SAND (SM): medium to coarse grained, trace clay, mica, light brown. -------------------------------------------------------------------- ----------~ RROROCK' PAlTRA Fm (Qp)' CLAYEY SANDSTONE: fine-grained. slightly weathered, dark brown. End of Test Pit at 10.0 feet. Groundwater not encountered during logging. Test Pit backfilled with soil cuttings on 12/20/99. SCALE: '"-5' (H-V) 't( I I I I I I SKETCH ~>.,: ~:;:-:...... . ..... ,- @i?'~~~"':"~ .' ..~ :1'" - '.,' .~. ~"I"'#"'\"" l~' .... .#'~ .f d.. L~ ..... ....."........ :..,~.~.:~ ~~'~~':~~ .~};(~~~?~~:. .' ~ -. . ..:. '.- '- .... " . . .. .. .... .. " . . . ~ - ..- ..:. '. .- ;",..... - ".,'.-:~ . -. . ...... .:- .-;-'-':- .:....::::.:>.::.....:._.~~.-;. .... '... -.. Qp . . -. . , ~ . . - . -. - ----. \' '. - ... . . ~ . .. ." - '. -" - ...'~ ~ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City ofTemecula I f- ~ f- a - S a LU f- u... ce ~ ::J Z (f) S f- ::J ce (f) LU 0 0 >-;;:' I ....J ceU f- CO ~ 0.3- 0 5 105 ca : N40E Drawing No. A-6 A,-" I I I I I I I I I I I I , I I I I I I I I I I Log of Test Pit No. TP-2 Dates Drilled: 12/20/99 Logged by: CWK Checked by: N/A MOC Equipment: BACKHOE, 24" Wide Driving Weight and Drop: Ground Surface Elevation(ft): 1124.0 Depth to Water(ft): None Encountered SUMMARY OF SUBSURFACE CONDITIONS AMPLE I- <fi. ~ This log is part of the report prepared by Converse for this project and should be 0 - s ~ read together with the report. This summary applies only at the location of the 0 W I- U LL a: ..... boring and at the time of drilling. Subsurface conditions may differ at other - I en => z I locations and may change at this location with the passage of time. The data l- => a: "- w S w I- presented is a simplification of accual conditions encountered. > >.< en "- <( (9 --' 0 ;..,", I w a: 0 a: => --' 0 a:<.J I- a (9 --' a en en 2 a.9- 0 A RTIFTCT A I. FlU (At)- 1\J SILTY SAND (SM): medium- to coarse-grained, wood, 2 116 .~.. . \concrete. loose, brown. AU.lfVTlTM (Qal)' SANDY CLAY (SC): fine grained sand, roots in upper 2 feet, 5 - ./ porous to 5 feet. dark brown. REDROf:K' PAlJRA Pm (Qp). . SANDSTONE: fine to medium grained, slightly porous to ! \ upper I foot. light brown. End of Test Pit at 8.0 feet. 10- Groundwater not encountered during logging. Test Pit backfilled with loose soil cuttings on 12/20/99. I- 15 - SCALE: '"-5' (H -V) SKETCH 111( : N70E It?:'-?--~.. ------'-'- Af . '.,:0--..--->'- . - .~. - ". ~- ~ ". --.."'.--'-<....;:;;!.,- -.- .;:",:.~ . -'. "'" '.'!::c' " .".....:., - :'- '~~'''- ..:~- 11:' -;. ~' ..~-:...:..: - .-- ..:.,:.,.:..-."?;', -,~", ~- --=;=-=9al (S~~ _' :. ': :-s: : ~- II :c:. - . , ~ '~..:~:;. -:.;'~\' ~~:~.:~:~.t:(~; :\?i:;t'''':~-(:':--:~~-~1' . ;.. Qp ......J,... . ~..;\} i~'~::'~-: :.:~...i.i..~.~.. ...;~'d:: ~ . ..#........ ...." ~ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOP:YIENT 99-8t-305-01 TRACT 29286 City of Temecula Drawing No. A-7 A.'\ I Log of Test Pit No. TP-3 Dates Drilled: 12/20/99 Logged by: CWK Checked by: N/A MOC I Equipment: BACKHOE, 24" Wide Driving Weight and Drop: I Ground Surface Elevation(ft): 1118.0 Depth to Water(ft): None Encountered I SUMMARY OF SUBSURFACE CONDITIONS AMPLE f- 'if!. f- This log is part of the report prepared by Converse for this project and should be 0 - S read together with the report. This summary applies only at the location of the 0 LJ.J f- ~ U LL a: - boring and at the time of drilling. Subsurface conditions may differ at other - :r: if) :J Z :r: locations and may change at this location with the passage of time. The data f- :J a: 0.. LJ.J S LJ.J f- presented is a simplification of actual conditions encountered. > ~ en 0.. <(CJ ...J 0 >-<;: :r: LJ.J a:O a: :J ...J 0 a: u f- 0 CJ...J 0 OJ OJ :;:;; oE: 0 BEDROCK' PAlTRA Fm (Qp). SANDSTONE: fine to coarse grained, upper 1 foot weathered, ,.. brown. 4 123 r 5 - End of Test Pit at 4.0 feet. Groundwater not encountered during logging. Test Pit backfIlled with soil cuttings on 12/20/99. 10- f-- 15 SCALE: 1--5' (H-V) SKETCH ~ : N45E I'" -. ':.'; });:~;' f' {'.': {;:;:~':.Y?-> .: ~.::: ._,.t;':" . I,'" . ..~ . . '..' . . , Qp . .... -. " " , '. :?>~ /i<~:.: . :,>;>~;.;.t:~ ::,! .,~ ..... '5 ~ ' .... .. ,. ..., .:.. '( l' ~ ' ,".. "., ~ t\:i" '. - # ~ .. ' .;\' I . I I I I I I I I I I I I I I @ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City ofTemecula Drawing No. A-8 I h6 I Log of Test Pit No. TP-4 Dates Drilled: 12/20/99 Logged by: CWK Checked by: MOC I Equipment: BACKHOE. 24" Wide I Ground Surface Elevation(ft): 1115.0 Driving Weight and Drop: Depth to Water(ft): N/A None Encountered I - - u - I I f- 0.. 0.. <!<.9 w a:a 0 <.9....J SUMMARY OF SUBSURFACE CONDITIONS This log is pare of the report prepared by Converse for this project and should be read together with the report. This surrunary applies only at the location of the boring and at the time of drilling. Subsurface conditions may differ at other locations and may change at this location with the passage of rime. The data presented is a simplification of actual conditions encountered. AMPLE f- "" f- a - S a w LL a: f- ~ ~ z Ul f- ~ a: S Ul w a a >-<;0 I ....J a: " f- ro :2; 0.3- a -- I w > :J a: ~ o ro I ALUJVTITM ((PI)' SILTY SAND (SM): fine to medium grained with mica, dark brown. I 5 14 101 col I I - 10 // WEATHERFO RFOROC.K 00.. -', SANDY CLAY-SILTY CLAY (SC-CL): trace coarse sand. o . . 0 \very dark brown. RRnROCK; 'PA 'lYRA - Fm' (QPj - - - - - - - - - - -. -.. - -. - - - -. - - - - - - - - - - - - - -. SILTY SANDSTONE-SANDSTONE: fine-grained, maSSIVe, trace clay, mica, dark brown. End of Test Pit at 11.0 feet. Groundwater not encountered during logging. Test Pit backfilled with soil cuttings on 12/20/99. r I I - 15 I SCALE: "-5' (H-V) SKETCH 11( : N70E I '. -~ ~ - . - ~.. . .. .' . ~ . .. ~ -:- - . - _:-:--._. -.--.Qal(SM) I ,. - -- .~. -. '. I . - . . .. ..... ... .. ...- ... ,.. . - - - ." .... weathered Qp zone l.:'~:,"-_;.'.~.,~-:.:.."o"',:', ".7 ';"::':;-.' ;-::..~., , ., .' ~ . . X ~ .:<~; .).- :i~~ ';"::.~~. ,:X' '~'::::'/:,~~:'iA?;;}'.;.; I .' '-'':. ...:. '.' ~~'i;"", '. ",. :', ....:. I I @ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City of Temecula Drawing No. A-9 I ~ I Dates Drilled: I Equipment: Ground Surface Elevation(ft): I I ~ - U I "- <I: (9 a:O (9....J I I f- "- UJ o I 1111 I 5 I I 10 I ,I 15 I Log of Test Pit No. TP-5 12120/99 Logged by: CWK BACKHOE. 24" Wide Driving Weight and Drop: 1125.0 Depth to Water(ft): SUMMARY OF SUBSURFACE CONDITIONS This log is part of the report prepared by Converse for this project and should be read together with the report. This summary applies only at the location of the boring and at the time of drilling. Subsurface conditions may differ at other locations and may change at this location with the passage of time. The data presented is a simplification of actual conditions encountered. AT T TNTlIM (Q31)' -, SILTY SAND (SM): tine-grained, gravel to 1", brown. REOROcr{:PAYTRAFm--(QP5.------ -- -- --- -- -- -- -- -- -- --. -- .. SANDSTONE: fine grained, uncememed. mica. massive, light brown. End of Test Pit at 6.0 feet. Groundwater not encountered during logging. Test Pit backfIlled with soil cuttings on 12120/99. SCALE: 1"-5' (H-V) I I I I I I _- A-" ~-... SKETCH --~'cial(SI ,,;_..:;, ~ :~~ ;. Ii',-. ___'__~ ....4. '\11 i 't.: ~ . ".. $' I .', ,. '.." . ~. ..,1,. \.. . .;. ~ '. '. . J ... ._, . '.' . ,I "- .,., c. " " - '~\:..~.~:.'.:.......f~;~.: '. . - --\ ~ ~;~;;.j,~~:.:._.~~.:.. ~;-;-;.::',..:};:;::- \', ,. , ~... '.:. ~. .... .~ J, '. " , " '" . : ( " . -,; .... .:~ :;:~ :.~ "-., , .. ..' ..:.. t' ~.......:.-;,....;,j.'..I.;....r.J ~ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City of Temecula I Checked by: NIA AMPLE UJ > :J cr: :::J o m . f- MOC f- ~ ;-: 0 - S 0 UJ t: LJ.. cr: ~ :::J Z <fJ S f- :::J cr: <fJ UJ 0 0 >-<;:: I ....J a: " f- m :2; 0.3- 0 5 120 ma None Encountered ~ : N40E Drawing No. A-lO A,t I log of Test Pit No. TP-6 Dates Drilled: 12120/99 Logged by: CWK Checked by: MOC I Equipment: BACKHOE, 24" Wide Driving Weight and Drop: N/A I Ground Surface Elevation(ft): 1130.0 Depth to Water(ft): None Encountered I SUMMARY OF SUBSURFACE CONDITIONS AMPLE f- "" f- 0 This log is part of the report prepared by Converse for this project and should be 0 - 3 ~ read together with the report. This summary applies only at the location of the 0 w t: - '=! boring and at the time of drilling. Subsurface conditions may differ at other LJ.. a:: ~ ::J Z I I locations and may change at this location with the passage of time. The data if) f- ::J a:: "- w 3 f- presented is a simplification of actual conditions encountered. > '" if) W "- <I: (CJ ....J 0 >-~ I w a:: 0 a:: ::J ....J 0 a::u f- 0 (CJ ....J 0 aJ aJ ~ oE: 0 ARTIFICIAl. FIT I (At). SILTY SAND (SM): fine to coarse grained, brown. 2 100 5 RF.DROCK' PAITRA Fm ( Qp)..:. ... CLAYEY SANDSTONE: medium to coarse grained, trace gravel, dark brown. End of Test Pit at 8.0 feet. 10 Groundwater not encountered during logging. Test Pit backfilled with soil cuttings on 12120/99. I- 15 - I SCALE: ,"-5' (H-V) SKETCH 'III( . E-W . ~ ,~-. . , ..-";.i..Th 'I.: # _, ,. :..,Af..:~:', ~ ~::\';1.~~~~ ',t., , . " ~ '.. ~. r-;-......~:Qp~ ~:-....\"::: .... ~.. . ..::.:.:.... . _;~1 ~..':-".-?"-"~':'.h"' 0:#.1 .. . - I I I I I I I I I I I I I I @ Converse Consultants Project Name. Project No. PROPOSED RESIDENTtAL DEVELOPME'-1T 99-81-305-01 TRACT 29286 City of Temecula Drawing No. A-ll I tw, I Dates Drilled: I Equipment: Ground Surface Elevation(ft): I I - - u - - I I f- a.. a.. <{l? w 0::0 0 l?....J I I I r 5 x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x 10 - ~ ~ ~ ~ x x x x X x x x ~ ~ x x I I I f- 15 I i I I I I I Log of Test Pit No. TP-7 12/20/99 Logged by: CWK BACKHOE. 24" Wide Driving Weight and Drop: None Encountered 1145.0 Depth to Water(ft): SUMMARY OF SUBSURFACE CONDITIONS This log is part of the report prepared by Converse for this project and should be read together with the report. This summary applies only at the location of the boring and at the time of drilling. Subsurface conditions may differ at orher locations and may change at this location with the passage of time. The data presented is a simplification of actual conditions encountered. BEDROCK- PAl IRA Fro (Qp). SANDSTONE-SILTY SANDSTONE:. tine-grained, light brown. ----------------------------------------------------------- ------------- ----- CLAYEY SILTSTONE: trace tine grained sand with mica. grayish brown. End of Test Pit at 12.0 feet. Groundwater not encountered during logging. Test Pit backftlled with soil cuttings on 12/20/99. SCALE: 1"-5' (H-V) I I I I SKETCH .. ~ -.. - - . - - - -- - -.-- - - - - - - ,. . - t-.-=-. -:=~-.- ~:. - ~":"_,:'::-=-'--" :._ -=-=_:_--7-'-.-:~~ . : - _ Qp (SM)-:-7 -.-~~- - o. _" \ '-..:: --: \ -:-; =- (MU- - , \..- - @ C~nverse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City ofTemecula I Checked by: N/A pAMPLE' w > :J a: :J o CD :: =-- ) MOC f- 'if!. ~ 0 - S 0 w f- LL a:: ~ :J Z (f) S f- :J 0:: (f) w 0 0 >-;;:: I ....J o::u f- Cll 2 o~ 0 15 101 'II( . N45E Drawing No. A-12 A<\ I Log of Test Pit No. TP-8 Dates Drilled: 12/20/99 Logged by: CWK Checked by: N/A MOC I Equipment: BACKHOE. 24" Wide I Ground Surface Elevation( ti): 1120.0 Driving Weight and Drop: Depth to Water(ti): None Encountered I ~ - U I a.. <(~ 0:0 ~-' SUMMARY OF SUBSURFACE CONDITIONS This log is part of the report prepared by Converse for this project and should be read together with the report. This summary applies only at the location of the boring and at the time of drilling. Subsurface conditions may differ at other locations and may change at this location with the passage of time. The data presented is a simplification of actual conditions encountered. AMPLE' I- ;Ji. I- 0 - S 0 W LJ.. 0: I- - ::J Z (f) w S I- ::J 0: > '-< (f) w a: -' 0 0 >-~ I ::J -' 0:" I- 0 (Jj (Jj :2; 0.3- 0 -- I I I- a.. w o I RF.nROCK" PAlTRA Fm (~ SANDSTONE: medium to coarse grained, with gravel, moderately cemented, brown to dark brown. I - 5 I - tine to medium grained, trace coarse sand. light brown I 10 End of Test Pit at 9.0 feet. Groundwater not encountered during logging. Test Pit backfilled with soil cuttings on 12/20/99. I 15 - I I SCALE: 1"-5' (H-V) SKETCH ... . N55E I 70. :;:.:,..:;~~ . ': ..-: ':,.1 i r .r~~...:~, "'::~ :~.. ,~...~"'.... .......:.,::;Qp (spf";"; ....~ ~ \. '. . # " :. . .'. <. ". ~ I ( '... ~.. , '. . ~.. -.. . "'~ ;.'... 'l". . . ....... . . - . - ~ I ~~ .'i-r'~"'~. "~~"~:".f.:t.......~ '~~"'+''''l'~t. "'." ..... .... ~'1. J." ';'. :.'...:...",;.~ ; '~>"1"'.' ..... ~ . ~ ~ - .. .... I \~-~ :;..~:: (~~)---. .-: :~-'-'_:~:.~ """ "- - - - .. - -:..: :" - .:_-- I .-:;... I I ~ Converse Consultants Project Name. Project No. PROPOSED RESIDENTIAL DEVELOPMENT 99-81-305-01 TRACT 29286 City ofTemecula Drawing No. A-13 I '50 'I - I I I I I I I I I I I I I ~ . o III -&.- ~ I I I SOIL CLASSIFICATION CHART MAJOR DIVISIONS CLEAN GRAVEL GRAVELS AND GRAVELLY (unu; OR 110 SOILS '.5) COARS( GRAVELS GRAINED llORl:.-.... WITH F'INES SOILS f1I CONlSt '-- REJ.u<<D ON ...l.'::"OA8LE NO. .. sot f1I roeS) CLEAN SANDS """'.- .... SAND or IiMTERW. AND (unu; OR 110 oS lAAGER SANOY '.5) TtMN NO. 20D SOILS S€Vt: SIZE ""'" .- .... SANDS WITH f1I CONlSt FINES 'RAC1OO _ON ...&"':"OA8LE NO. .. S€VE f1I hICS) SILTS ~ FINE AND UlllT u:ss GRAINED CLAYS .- .. SOILS """'.- .... or "'1[-" IS 5MM.t.!R SILTS .- IIQ. 200 ~....r S€Vt: SIlt AND GRtATtR TKUI CLAYS .. HIGHI. Y ORGANIC SOILS SYMBOLS TYPICAL GRAPH LETTER DESCRIPTIONS GW --- GaWQ. - SMIO ..-a. uftLI: 0.10 I'II<<S GP ~Y-G8IClCO~ C*lCL -1IlIIO~ uftLI: ... 10 ntCS Glol Sl,rr C'aMCd. GlIMlCL - s.a ~ SIL' -'UCS GC a.an~GJIIIII1- SIlItG- Q#-'\IIItS SW 1---- ~...: -. uftLI: (It SP ......y-GlIJIIIm SMCl'L ~TSMlO.UIILC(It ... .... Slol ." .... s.o .. IlL' - SC a.an S/IIIOI" SMe .. a.rr - JiGIGIIIC "IS __ tOr loll r.c ..... ICD ~ "IYQltCLMC't'NC _0I00llItf..1S........1I\.IIIOIt' IIGllMC a.rs tit '-'lII' to Cl --. CMIICu." a.ws. IMCJf a.ws. SI.'" CloDS, ~ CU'rS Ol ClIGMC _IS ... CIIGMC _"Cl.II'IIrI* -- lolH ~.rs.1ICllCIIlUS (II D'" U .1'1III- 01 ..'" SOd CH lJCIIGlIIICa..sar...~ OH ClMlMC Q.II'IS tII tICDUI ID MOl 1lUSIOI\'. 0I0lIC .... PT 1.....--.... .... ..... GIIGMC co.rtIIIS NOTE: DuAl. 5't'IlIiOlS ARE USlD TO INDCATt EIOAD(IUC so.. CLASSlFCA1'OIS H.5.A. : Mollo.- 51..... AuoI' ...-r !"tPI' BORING LOG SYMBOLS LA8:)RAT(lR't TtSTIhG ~TOIS C1~ _WTRA~ Tf"'U 5cI'lbClttat~..~..." AS'hlI D-l"-&I SIOftlIDtd '1a1 w.ttlOll ~11rE'~~~.JOI.Dift.-:::W' dl'ioIeft nawr ...-.. Net '<<OWefJ ,.,...t:CII'&'"a'hnll ~SftOM\",,~B) =%- -....""'..... 5oftcIr~ t:l':"~ ~liOft Cutwe '" ... .. .. ': -- muIi!Il ~"""tOl'Mt... ......- Direcl Sbeot Csinl)Ie ~) unc:onIiNcI~ TM:alol Comprea:oft -- . .. ... "" ,. .. , ... , .. .. - l'lI<11....nllll.lt~r ,.."._ft'R_rnD'lll~ ~-"'1TD &MJ'D '-I.-'l: .~ UNIRED SOIL CLASSIRCATION AND KEY TO BORING LOG SYMBOLS PROPOSED RESIDENTIAL DEVELOPMENT. CITY OF TEMECULA. CALIFORNIA For: lennor Homes @ Converse Consultants I I - TRACT 29286 PrOtecl No. 99-81-305-01 Oro.inQ No. A-14 -5, I I I I I I I I I I I I I I I I I I I M. J. Schiff & Associates, Inc. Consulting Corrosion Engineers - Since 1959 1308 lYlonte\lista Avenue, Suite 6 Upland, CA 91786-8224 Phone: 909/931-1360 Table 1 - Laboratory Tests on Soil Samples Lennar Homes, Temecula, CA Your #99-81-305-01, i'dJS&A #99002-30 1-Jan-00 Sample ID TP-I 3~4' Resistivity as-received saturated Units ohm-em ohm-em 35,000 3,550 7.2 3,800' 860 pH 7.3 Electrical Conductivity mS/cm 0.07 0.2] Chemical Analyses Cations calcium Ca2+ mglkg magnesium Ma2+ mglkg 0 sodium Na'+ mglkg Anions carbonate CO;- mglkg bicarbonate HCO,I- mglkg chloride Cl'- rnglkg sulfate SO/, mglkg Other Tests ammonium NH41+ mglkg nitrate NO,'- mglkg sulfide S', qual Redox mv 24 16 10 17 NO 145 NO NO 92 226 18 ]70 NO NO na na na na na na na na l;:i.p,~~bN~e~"m~I!!!~>"~"""<"~'='~;~","""",,'_~.~~'"iIl:~-:k~''u'~~::Z'i.W?~~;;;.1.;:.':',""-..'!-.;.,;:.(~::.:,,.~~;;'~'~;;;\i~~:-.~c-:.;';ZP:" .;::;~ Electrical conductivity in milIisiemens/cm and chemical analysis were made on a 1:5 soil-ta-water extract. mglkg = milligrams per kilogram (parts per million) of dry soil. Redox = oxidation-reduction potential in millivolts NO = not detected na = not analyzed Page] of I ~z,. I I I I I I I I I I I I I I I I I I I APPENDIX B LABORATORY TESTING PROGRAM 6?/ I I I I I I I I I I II I I I I I I I I 99-81-305-01 January 20, 2000 Page B-1 APPENDIX B LABORATORY TESTING PROGRAM Geotechnical tests were conducted in the Converse laboratory on representative samples for the purpose of evaluating physical properties and engineering characteristics. Test results are presented on the exploration logs and in this appendix. A summary of the various laboratory tests conducted is presented below. 7n Situ Moisture Content and Dry Density Data obtained from these tests, performed on relatively undisturbed ring samples obtained from the field, was used to aid in the classification and correlation of the earth materials and to provide qualitative information regarding strength and compressibility. The percent of moisture as a function of dry weight, and the encountered dry density in units of pounds per cubic foot (pcf) are provided in the right-hand columns on the exploration logs. Grain-Size Analysis The grain-size distribution covers the quantitative distribution of particle sizes in soils. The particle distribution is used to aid in the classification of the soils. A total of five tests were performed on representative samples in accordance with ASTM Standard D422-63. For test results, see Drawing No. B-1, Gradation Curves. Laboratory Maximum Density and Optimum Moisture Tests Laboratory maximum density and optimum moisture tests were performed on representative bulk samples of the site materials. These tests were performed in accordance with the ASTM D1557-91 laboratory procedure. The results are presented in Drawing No. B-2, Compaction Test Results, Consolidation Tests Data obtained from this test, performed on two (2) relatively undisturbed soil samples, were used to evaluate the settlement characteristics of on-site soils under load. This test involved loading a specimen into the test apparatus, which contained porous stones to accommodate vertical drainage during testing. The specimen was then normally loaded. Resulting vertical deflections were recorded at various time periods. The load was increased after the sample reached a reasonable state of equilibrium. The samples were tested under field moisture conditions up to a normal load of 2 kips per square -foot. The samples were then submerged with water. Test results are presented on Drawings No. B-3 and B-4, Consolidation Test. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.gir 5~ I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20. 2000 Page B-2 Collapse Tests To evaluate the moisture sensitivity (collapsibility) of the encountered soils, ring samples were loaded up to approximately two kips per square foot (ksf), allowed to stabilize under load, and then submerged. The results of these tests are summarized in Table No. B-1, Collapse Results. Table No. B-1, Collapse Results BORING. NO./DEPTH TEST - SOIL DESCRIPTION PERCENT COLLAPSE BH-l/3' Collapse Silty Sand (SM) 0.1 BH-l/5' Collapse Clayey Sand (SC) 0.0 BH-5/3' Collapse Silty Sand (SM) 2.2 TP-4/5' Collapse Silty Sand (SM) 0.2 BH-l/25' Consolidation Silty Claystone 0.1 BH-5/5' Consolidation Silty Sand ISM) 0.0 Expansion Index Tests One (1) representative bulk sample was tested for expansion index to evaluate the expansion potential of material encountered at the borrow site. The test was conducted in accordance with UBC Standard 29-2. For test results, see Table No. B-2, Summary of Expansion Index Test Results. Table No. B-2, Summary of Expansion Index Test Results BORING NO./DEPTH SOIL DESCRIPTION EXPANSION INDEX (feet) BH-4/0-5' Clayey Sandstone, fine to medium grained, 2 brown Direct Shear Tests Direct shear tests were performed on undisturbed and remolded samples at soaked moisture conditions. Samples contained in brass sampler rings were placed one at a time directly into the test apparatus and subjected to a range of normal loads appropriate for the anticipated conditions. Each sample was then sheared at a constant strain rate of 0.05 inch/minute. Shear deformation was recorded until a maximum of about 0.50-inch shear displacement was achieved. Peak strength was selected from the shear-stress deformation data and plotted to determine the shear strength parameters. For test data, including sample density and moisture content, see Drawings No. 8-5 and B-6, Direct Shear Tests. ~ ~ Converse Consultants CCIENTlOFFICE\JOBFILE\ 1999\81 \99-305\99-305-1-.9Ir ?4 I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page B-3 Resistance R-Value Test One bulk soil sample was tested to determine the resistance (R)-value in accordance with the State of California Test Method No. 301-G (ASTM Standard D2844). Result of the R-value test is presented in Table No. B-3, Result of R-value Test. Table No. B-3, Result of R-value Test SAMPLE RESISTANCE BORING NO. DEPTH SOIL DESCRIPTION (feet) - R-VALUE* - TP-3 3'.4' Sandstone, fine grained with mica, light brown. 22 . By exudation Corrosivity Tests Two bulk samples of the site soils were tested by M. J. Schiff and Associates of Claremont, California, to evaluate soil corrosivity with respect to common construction materials. Results are included at the end of this appendix. Sample Storage Soil samples presently stored in our laboratory will be discarded 30 days after the date of this report unless this office receives a specific request to retain the samples for a longer period. ~ ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81 \99-305\99-305-1-.9Ir ~ I I I I I I I I I II , I I I I I I I I I U.S. SIEVE OPENING IN INCHES I 4 2 1 112 3 u.S. SIEVE NUMBERS 6 10 16 30 50 100 I HYDROMETER 200 6 3 1.5 3/4 8 4 8 14 20 40 70 140 II I I I ~. k.. "I ~ I I1II1 I I ~ 1\- ~ I III I I 1\ \ I' "'i \ \ II ~ ~ \\ il \ I. ~ , \ \ \ 100 90 80 P E R70 c E N T 60 F I N E50 R B Y 40 E I G30 H T 20 10 o 100 10 1 0.1 om 0.001 GRAIN SIZE IN MILLIMETERS COBBLES GRAVEL SAND SILT OR CLAY coarse tine coarse medium fme Boring No. Depth(ft Classification MC% LL PL PI Cc Cu . BH-I 15.0 SANDSTONE I 1.34 6.5 . BH-4 10.0 SILTY SANDSTONE 8 ... TP-5 3.0 SANDSTONE 5 Boring No. Depth(ft D100 D60 D30 DlO % Gravel % Sand %Silt % Clay . BH-I 15.0 9.50 0.70 0.317 O. 1069 1.9 90.4 7.7 . BH-4 10.0 9.50 0.20 0.4 64.6 35.0 ... TP-5 3.0 9.50 0.19 0.5 57.1 42.4 PROJECT: PROPOSED RESIDENTIAL DEVELOPMENT TRACT 29286 City ofTemecula JOB NO.: 99-81-305-01 DATE: 1119/00 Drawing No. B-1 ~ Converse Consultants GRADATION CURVES ~1, I I I I I I I I I I I I I I 110 5 15 20 MOISTURE CONTENT, % TEST METHOD: ASTM D1557-91. 4" Mold 25 30 130 ... <.) 0. ~ - ~ ~ o ~ o 120 100 o Layers: 5 Blows: 25 /layer Hammer: 10 lb. Fall: 18 in. Mold Diameter: 4 in. I I I I I Symbol Boring No. Depth(ft) Soil Classification Optimum Moisture Content % Maximum Dry Density, pef . BH-2 0.0 SILTY SANDSTONE . BH-3 10.0 CLAYSTONE 10.0 12.0 128.5 124.0 PROJECT: PROPOSED RESIDENTIAL DEVELOPMENT TRACT 29286 JOB NO.: City of Temecula DATE: ~ Converse Consultants COMPACTION TEST RESULTS 99-81-305-01 1/19/00 Drawing No. B-2 I I I I I I I I I I I I I I I I I I I p e r c e n t 1 ~ ----- ------ '--, "'" 2 ~ 4 ~ ~ 6 i'\ 1\ - - 1\ 8 \1 . 0 " 2 ~ \ ~ 1----\ ------. ~ - 4 II 6 8 0 1000 10000 105 S T R A I N 1 1 1 1 2 100 STRESS. psi Boring No.: Soil Classification: BH-I Depth(ft): 25.0 SIL TY CLAYSTONE 74.4 Moisture Content(%): 44.4 1.26 Initial Degree of Saturation(%): 94.9 I. 04 Degree of Saturation After Test( %): 100.0 Dry Density(pct): Initial Void Ratio: Void Ratio After Test: PROJECT: PROPOSED RESIDENTIAL DEVELOPMENT TRACT 29286 JOB NO.: City ofTemoo"!. DATE: ~ Converse Consultants CONSOLIDATION TEST 99-81-305-01 1/20/00 Drawing No. B-3 ~ I I I I I I I I I I I I I I I I I I I o ~ ---------- r-----.- ~r- ~ ~ ~ "'- "'" I I I I~ - I I -- 1000 10000 105 2 4 6 S T R A I N 8 10 p e r c e n t 12 14 16 18 20 100 STRESS. psf Boring No.: Soil Classification: BH-5 Depth(ft): 5.0 SILTY SAND (SM) 124.4 Moisture Content(%): 12.4 0.35 Initial Degree of Saturation(%): 94.1 0.27 Degree of Saturation After Test(%): 99.9 Dry Density(pct): Initial Void Ratio: Void Ratio After Test: PROJECT: PROPOSED RESIDENTIAL DEVELOPMENT TRACT 29286 City of Temecula JOB NO.: DATE: 99-81-305-01 1119/00 Drawing No. B-4 ~ Converse Consultants CONSOLIDATION TEST (i;D I I I I I I I I I I I I I I I I I I I 3000 2500 S 2000 H E A R S T R 1500 E N G T H P s f 1000 500 o o 1000 500 1500 2000 NORMAL PRESSURE. psf Boring No.: BH-2 Depth(ft): 0.0 Soil Classification: SILTY SANDSTONE Dry Density(pct): 117.7 Moisture Content(%): 16.6 Internal Friction Angle(degree): 28 Cohesion(pst): 100 Note: PROJECT: PROPOSED RESIDENTIAL DEVELOPMENT TRACT 29286 JOB NO.: City ofTemecula DATE: ~ Converse Consultants DIRECT SHEAR TEST 2500 3000 99-81-305-01 1/19100 Drawing No. B-5 (A I I I I I I I I I I I I I I I I I I I 3000 2500 S 2000 H E A R S T R 1500 E N G T H P s f 1000 . 500 o o 500 1000 1500 2000 NORMAL PRESSURE. psf Boring No.: BH-3 Soil Classification: CLAYSTONE Dry Density(pcf): 98.2 Internal Friction Angle(degree): 20 Note: Depth(ft): 10.0 Moisture Content(%): 27.3 Cohesion(psf): 300 PROJECT: PROPOSED RESIDENTIAL DEVELOPMENT TRACT 29286 City of Temecula $ Converse Consultants DIRECT SHEAR TEST JOB NO.: DATE: 2500 3000 99-81-305-01 1/20/00 Drawing No. B-6 (it. I I I I I I I I I I I I I I I I I I I APPENDIX C RECOMMENDED EARTHWORK SPECIFICATIONS vb I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page C-l APPENDIX C RECOMMENDED EARTHWORK SPECIFICATIONS Grading · Areas to receive compacted fill shall be stripped of all vegetation, organic, debris and existing structure remnants. All undocumented fill materials, if any, shall be excavated and removed. Any other unsuitable soils shall be excavated as recommended by Converse. All areas that are to receive compacted fill shaW be observed by Converse prior to placement of fill. . Subsequent to the removal of unsuitable materials, subgrade soil surfaces that will receive compacted fill shall be scarified to a depth of at least 6 inches. The scarified soil shall be moisture-conditioned to within three percent of optimum moisture content. Scarified soil shall be compacted to at least a relative compaction of 90%. Relative compaction is defined as the ratio of the in-place soil density to the laboratory maximum dry density as determined by the ASTM Standard D1557-91 test procedure. . Fill shall be placed in suitable lifts, with lift thickness modified as necessary to achieve adequate compaction. All fill soils shall be compacted mechanically throughout to the specified density at moisture content within three percent of optimum. All fill thicker than 20 feet should be compacted to 95 percent relative compaction. All other fill, unless otherwise specified to be compacted to 95 percent, shall be compacted to at least a minimum relative compaction of 90%. Fill shall be benched into unyielding bedrock on slopes steeper than 5: 1 (horizontal: vertical). Where fill is to be placed above cut slopes or natural slopes, fill shall be benched into bedrock as shown on Drawings No. C-l and C-2. The field density of the compacted soil shall be measured by the ASTM D1556-90 or D2922-96 test methods or equivalent. . Fill soils shall consist of excavated on-site soils essentially cleaned of organic and deleterious material or imported soils approved by Converse. Imported fill shall be granular and non-expansive with an Expansion Index (Ell less than 30, as defined by the Uniform Building Code (UBC) Standard 18-2. Rocks larger than six inches in diameter shall not be placed as fill unless they are sufficiently broken down. Converse shall evaluate and/or test import materials for conformance with specifications prior to delivery to the site. The contractor shall notify Converse at least two normal working days prior to importing fill to the site. . Converse shall observe the placement of compacted fill and conduct in-place field density tests on the compacted fill to check for adequate moisture content and ~ ~ Converse Consultants CCIENTlOFFICEIJOBFILEI 1999181 199-305199-305-1-.9ir fA I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page C-2 the required relative compaction. Where less than the specified relative compaction is indicated, additional compactive effort shall be applied and the soil moisture-conditioned as necessary until the specified relative compaction is attained. The contractor shall provide level testing pads upon which the soils engineer can conduct field density tests. The contractor shall provide safe and timely access for Converse personnel throughout the grading site to allow continued monitoring and testing. · The contractor shall be responsible for maintaining stable and safe conditions during construction. Trench Backfill Trench excavations to receive backfill shall be free of trash, debris or other unsatisfactory materials at the time of backfill placement. · Trench backfill shall be compacted to a minimum relative compaction of 90 percent as per ASTM Standard D1557-91. At least the upper twelve inches of trench underlying pavements should be compacted to at least 95 percent relative compaction. · Rocks larger than one inch should not be placed within 12 inches of the top of the pipeline or within the upper 12 inches of pavement or structure subgrade. No more than 30 percent of the backfill volume shall be larger than 3/4-inch in largest dimension diameter, and rocks shall be well mixed with finer soil. · The pipe design engineer should select bedding material for the pipe. Bedding materials should have a Sand Equivalent (SE) greater than or equal to 30, as determined by the ASTM Standard D2419-95 Test Method. · Trench backfill shall be compacted by mechanical methods, such as sheepsfoot, vibrating or pneumatic rollers, or mechanical tampers, to achieve the density specified herein. The backfill materials shall be brought to within three percent of optimum moisture cqntent, then placed in horizontal layers. The thickness of uncompacted layers should not exceed eight inches. Each layer shall be evenly spread, moistened or dried as necessary, and then tamped or rolled until the specified density has been achieved. . The contractor shall select the equipment and processes to be used to achieve the specified density without damage to adjacent ground and completed work. . The field density of the compacted soil shall be measured by the ASTM Standard D1556-90 or ASTM Standard D2922-96 test method or equivalent. ~ ~ Converse Consultants CCIENTIOFFICE\JOBFILEI 1999181 199-305199-305-1-.gl, 4.-6 I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page C-3 · Observation and field tests should be performed by Converse during construction to confirm that the required degree of compaction has been obtained. Where compaction is less than that specified, additional compactive effort shall be made with adjustment of the moisture content as necessary until the specified compaction is obtained. . It should be the responsibility of the contractor to maintain safe conditions during cut and/or fill operations. . Trench backfill shall not be placed, spread or rolled during unfavorable weather conditions. When the work is interrupted by heavy rain, fill operations shall not be resumed until field tests by the project's geotechnical consultant indicate that the moisture content and density of the fill are as previously specified. Erosion Control . Fill and cut slopes shall be graded and landscaped to reduce water-induced surficial erosion/sloughing. Permanent erosion control measures shall be initiated immediately after completion of slope construction. . All interceptor ditches, drainage terraces, down-drains and any other drainage devices shall be maintained and kept clear of debris. Runoff shall be directed to a suitable non-erosive drainage device, and shall not flow uncontrolled off-site. . A suitable proportion of slope plantings shall have root systems that will develop well below 3 feet, such as drought-resistant shrubs and low trees or equivalent. Intervening areas shall be planted with lightweight surface plantings with shallower root systems. In any event, lightweight, low-moisture planting shall be used. . Construction delays, climate/weather conditions, and plant growth rates may be such that additional short-term, nonplant erosion control measures may be needed, including matting, netting, sprayed compounds, deep (5 feet) staking, etc. These measures shall be submitted to Converse for review. . Rodent burrowing, human trespass (footprints), small concentrations or uncontrolled surface/subsurface water, or poor compaction of utility trench backfill on slopes shall be repaired and controlled as soon as possible. . All possible precautions shall be taken to maintain moderate, uniform soil moisture. Slope irrigation systems shall be properly operated and maintained, and system controls shall be placed under continued control by a landscape architect or similar qualified person. ~ ~ Converse Consultants CCIENT\OFFICE\JOBFILE\ 1999\81 \99-305\99-305-1-.9ir c.,~ I I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page C-4 · If completion of new slopes occurs during the rainy season, contingency plans shall be developed to provide prompt temporary protection against major erosion/sloughing. Offside improvement shall be protected from site runoff. . The Contractor shall repair any erosion damage that occurs prior to the completion of the project. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.9ir ~"1 I I I I I I I I I I I I CUT/Fill COHTACT SHOWH OH GiUOIHG PLlH CUT.'AlL COHnCT TO BE SHOWN ON -'S-BUllr CQLlP8'E.'iT l.UTEiUAl. 1 N,ru;Ul G;UOEl . - -r::s'. - - -- -- - -- .- ---'I .. - .' -- .'. ------: . '.-' ..~.. . CUT SlOPE . - .. -.. ,,---- . - .. ---- . 1 ~.,>o. __ J c.oWP:iE.1fT J.U.TEnl-'l = <= CUT SlOP€ TO BE CONSTRUCTEa PRIOR TO l'UCEIlEHl' OF FIlL (F:rWAV IH CO"P:TE!l1' WAT- E~'AL WIHI"U" WlOTH OF IS F<:T OR AS RECO....EHOEa BY THE SOil ENGlHEER I I I I Q.""" '" l . -. ;....:--- . -\ - -..;.-:-: ...- ....:-'-"'"~.. <-""i~v.C.': ::..-:- - . .J-. ,.su~~B\.- - .'.- - <lol~U _ .-" ~- ::.--:-:-- . VMIUat..:. ...'".. .. .: Il,IIH. ,;. -= "IN'''UIl HEIGH"( OF BENCHES IS .. F:::t OR, "S RECOu.. WENOEO a~ THE' SOil ENGI- l .EE~ J.lIHIJ.l:UU l' TILT 5J.CX OR l<; SLOPE {WHICHEVEillS GRE.lTE.<j TYPICAL FILL ABOVE CUT SLOPE PROPOSED RESIDENTIAL DEVELOPMENT, TENTATIVE TRACT 29286 City of Temecula, California For: Lennar Homes I I I @ Converse Consultants Project No. 99-81-305-01 Figure No. C-1 ~ I I I I I I I I I I I I I I I I I I I ......... ... . . '.' 00.. .- : '-': :COMPACTED FILl. : . -. , ... . PROJECT~ PLANE_ .' .~..:.::~.~...;':.~-j:;:}+ji::t4f2i.~.. 1 to 1 maxantJrn from \ . : ...... ;....-:-:-.--=-; : :,:"'.."'" . ,."- tee of 3100e to . '. ;,.....- .. :.~. .-..~" approved ~d . . . : ~-=-: ,'.: ': ....x. :.' 7" .:.....:.--:;."'1~t.: ~., . 1 ' NATURAL .>,-. '.: . ':'-' :;.> 4 T'Pl<:a. . GROUNO .: :--::./':"-:-::-':~:~'" 11 ':. .x.;.....~:~.: ".: ~.~:.' 9ENa-IHSGHT ~ ---:. 2~ I.IIN::"..::' BEHQi I '~"""""'~.:..-:". 2' lAIN. KEY CEl'TH FILL OVER NATURAL SLOPE PROPOSED RESIDENTIAL DEVELOPMENT, TENTATIVE TRACT 29286 City of Temecula, California For: Lennar Homes Project No. 99-81-305-01 @ Converse Consultants Figure No. C-2 CA I I I I I I I I I I I I I I I I I I I APPENDIX D SLOPE STABILITY ANALYSIS I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page D-l APPENDIX 0 SLOPE STABILITY ANALYSES Stability of slopes on this project were evaluated by using computer program PCSTABL SM, developed at the University of Purdue (1996 version). peST ABL SM is written in FORTRAN IV source language for the general slope stability problems using the two-dimensional limiting equilibrium method. The calculation of the factor of safety against instability of a slope is- performed by a method of slices. The particular methods employed in this version are the modified Bishop Method, applicable to circular shaped failure surfaces, and the simplified Janbu Method, applicable to failure of surfaces of general slopes. The program can use three different techniques to generate potential failure surfaces for subsequent determination of the more critical surfaces and their corresponding factors of safety. One technique generates circular surfaces; another, surface of sliding block character; and a third, more general irregular surfaces of random shape. Global Stability According to the rough grading plan for the project, the cut slopes will be constructed no steeper than 2:1 (horizontal: vertical). The following strength parameters were used in the slope stability analysis below in Table D-l, Strength Parameters. Table No. 0-1, Strength Parameters WET EFFECTIVE MATERIAL SOIL DESCRIPTION DENSITY COHESION INTERNAL SEGMENT (pet) (psf) FRICTION ANGLE Native soil SILTY SAND ISM). fine to medium 120 100 28 grained, brown Based on the grading plan, cut and ill slopes are not expected to be graded steeper than 2: 1 (H:V) and are not expected to exceed 20 feet in height. The result of the slope stability analyses performed for the proposed cut/fill indicated a static factor of safety of 1.5. The pseudostatic factor of safety was found to be 1.1. Therefore, the proposed slopes are expected to be stable. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.gir 10 I I I I I I I I I I I I I I I I I I I 99-81-305-01 January 20, 2000 Page D-2 Surficial Stability Surficial slope stability analysis was performed by using parameters listed below: Slope inclination (horizontal: vertical) Depth of saturation Total unit weight of soil Slope angle Internal friction angle Cohesion = 2:1 = 3 ft. = 120 pounds per cubic foot = 26 degrees = 28 degrees = 100 pounds per square foot The result of the surficial slope stability analyses indicated that the factor of safety is 1.2. Our analyses indicate that the slopes, if constructed according to the rough grading plan and recommendations contained herein, should have an adequate safety factor. ~ ~ Converse Consultants CCIENTIOFFICEIJOBFILEI 1999181 199-305199-305-1-.9Ir \\ I ...-z.\.. I I I I I I I I I I I I I I I -; (1) " :s: o '" ~ n ~ ::+ c;' .. n to to W o '" o .... -0 r- -; '" -< ;:.: C Gl :I> Z ;:.: C Gl :I> Z m Z -; :r :D :I> o .... .... to 6 o w 01> to .. 3 -< -;;; :i> c x ;;;' ~ ~ '" '" 0 '" 0 '" 0 0 0 0 - 'F I;;"H~UN_" ................................................" CnCnCnCnc"c"c,c,c,,~C/) 1\J.........Ol.OlOO'lU'tNtD '" o 00 z-<", ~~ g, c: .... €"s.c;t '" 0 _ o :::~a c:'" -c2.~ l'l-~ .:::~~ -0 . ~ ,0 __0 ,,0'" .-0 ::d~ !.. ,,0 -, N o o i:i::r>~ S;l ~J; g. -cg "04' .0"0 -.0 .. - 3 < 0 . . " o '" o ~ o o -0 n rn -;~ :1>'" ",0 r- '" ." rn 3 -. '" " 0 II 0 .... 01> to X :i> '" x '" Cfj" 0 e o 0"0 :cg: o .;~~ , - _0 '" zS:P. 0-0 . . N n. o w o o w '" o W r- o ""D m w ~ )> to - r- ::::j -< )> z )> r- -< W - W ;;:0 m w c r- ~ W "T1()-" 0-' ::c ::'<0 rO-" ,,-0 ::>-IUl ::>"m ~30 I~::C oc:m 3-Ul .,- ,,' 0 ",()m ., Z ~::i 0)> 3 r (li'o m < m r o -" $: m Z .-1 -I m Z -I )> -I <: m -I :JJ )> () -I '" (0 '" CD 0) ~t) (") o :J < CD .., (/l CD (") o :J (/l s:: ;:; Ql :J ... (/l -" o roo ~ z o "T1 cO' c: ;;; Z o I .. o o I I CD CD , (Xl ..... , W o (J'1 , o ..... o , .... I I I I I I I I I I I I I I I I I I I - - -< ~ :i> ~ x 0;' ~ ~ '" '" 0 '" 0 '" 0 0 0 0 l-u~~~~ N_'" :~..lo"'''''''''''''''''''''''''''''T1 :...:...:...:...:...:......:...:...OW -...l......cncnt11WNN...CO - Z-<", o:tl E. , 0- c ~ :oS,;' 0 a::i c'" <:: _::l~ "CI ="r:; o " 0 =:::~ ". 0- ,n ~ .:;-iDg. 0 ~r;: 0 _G _. ". -, '" Q:~~ .'0 " lQlC ~. -ii"g -i ll> ::s S o .. ~ (") ~ ;:;. r;' !!:. (") '" '" '" o Ul o ~ "tl r- -i m -< ^ C G'l :I> Z ^ C G'l :I> Z m Z -I :t: :D :I> o ~ , ~ '" 6 o '" :!> 00 C> 3 ,,:!' ..." o "ll'>O 3~; o n" o :cg: ,;~~ , " _0 '" z!:;:P. . -. , .. 0' . '" o 00 '" o - o o "tl (") en -1- :1>'" mO r- Ul ." en 3 -. '" ::s 0 II 0 ~ o 00 >< :i>", x '" in' 0 ;t w o o w '" o ... o o C/) r o "'tI m C/) ~ ~ OJ - r - ~ -< ~ Z ~ r -< C/) - C/) :;0 m C/) c r ~ C/) "()" Q ~.:o ..< 0 ,0" CD-O ".....en "CDm ~3o I~:JJ ocm 3-en ., - CD' 0 ",()m ., Z =-i 0':; 3 ' w'o m < m , o " s: m Z ,..... ..... m Z ..... :l> ..... <: m ..... :D :l> () ..... '" c.o '" (Xl en " (3 ro' ~ z o l.P l.P Co -l , W o C11 , o -l ~t) n o ~ < CD ., III CD n o ~ III r::: - D) ~ - III " <<i' c co z o o , N ti'}.. I I I I I I I I I I I I I I I I I I I ~ i O~~~ ~#~ Assumed Parameters: z - Depth of Saturation (feet) I Slope Angle (degrees) Y w Unit weight of water (pet) Y t Saturated Unit Weight of soil (pcf) <\> Apparent Angle of Internal Friction C Apparent cohesion (psf) FS= c+ 0 tan<\> T C + (Y t - Y w) Z cos2i tar<\> Y t Z sin i cos i = FS = 1.2 =3.0 =26.6 = 62.4 = 120.0 =28.0 = 100.0 SURFICIAL SLOPE STABILITY ANALYSIS PROPOSED RESIDENTIAL DEVELOPMENT, TENTATIVE TRACT 29286 City of Temecula, California For: Lennar Homes @ Converse Consultants Project No. 99-81-305-01 Figure No. 0-3 1t