Loading...
HomeMy WebLinkAboutGeotechnical Reports U B. GEOTECHrTICAL REPORTS Converse Consultants Inland Empire consulting Engineers and Geologists 630 East Brier Drive. Suite 100 San Bernartlino. California 92408 O Telephone 714 /8898004 FAX 714 8894830 ~~ GEOTECHNICAL INVESTIGATION Tentative Tracts 25213, 25214, 25215 Campos Verdes Residential Development Temecula, California O PREPARED FOR Mesa Homes 28765 Single Oak Drive Suite 100 Temecula, California 92390 CCIE Project No. 89-81-165-01 May 10, 1990 Revised June 1, 1990 O Awhouy Owned Subsidiary of The Converse Professional Group Converse Consultants Inland Empire 630 East Brier Drive. Suite .00 San Bernardino. California 92408 • June 1, 1990 Mesa Homes 28765 Single Oak Drive Suite 100 Rancho California, California 92390 Attention: Mr. Csaba F. Ko Consulting Engineers and Geologists Telephone 714 /B89-8004 FAX 7 t 4 8894830 Subject: GEOTECHNICAL INVESTIGATION Tentative Tracts 25213, 25214, and 25215 Campos Verdes Residential Development Temecula, Caiifornia CCIE Project No. 89-81-165-01 Gentlemen: Enclosed are the findings of our geotechnical investigation performed for the subject Tracts, Campos Verdes Residential Development, in Temecula, California. Materials encountered in the exploratory excavations generally consisted of loose to medium dense topsoil underlain by alluvial soils and soft sedimentary bedrock of the Pauba Formation. The topsoil and alluvial soils consist primarily of clayey and silty sands. The Pauba Formation bedrock consists of sandstone, claystone and siltstone. The sandstone generally has interbedded claystone and siltstone layers. Groundwater was encountered in exploratory borings BH-5 and BH-7 at depths of 27 feet and 23 feet, respectively. Based on the type of soils underlying the site and the depth to groundwater, it is our opinion that liquefaction will not likely occur at the site. The soils, bedrock, and groundwater conditions are such that the proposed development can proceed as planned. Results of our investigation indicate that the site is suitable for the proposed residential development, provided that the recommendations contained herein are incorporated into final development plans. Development of the tract will involve conventional mass grading. Anticipated depths of overexcavation in proposed fill areas are indicated on the enclosed maps and discussed in the A-Whplly Ownetl SuUSitl~ary of T71e Cpnve(se Profe$slonai Grpup Mesa Homes CCIE Project No. 89-81-165-01 June 1, 1990 Page 2 appropriate sections of this report. Conventional 2:1 (horizontal to vertical) cut and fill slopes are proposed, with structure setbacks as recommended herein. Spread footings may be used to support the proposed residential structures. We appreciate this opportunity to be of service. If you have any questions, please feel free to contact our office. Very truly yours, CONVERSE CONSULTANTS INLAND EMPIRE Robert W. Rogers Vice President OH/DCP/GFR/SCH/RWR:wpd Dist: 6/Addressee 1/Doug Wood and Associates 1/Dr. Roy J. Shlemon 1/Turrini and Brink Attention: Mr. Eric Boos Converse Consultants Inland Empire TABLE OF CONTENTS Page n LJ \J 1.0 INTRODUCTION .......................................... 1 2.0 PROJECT DESCRIPTION ................................... 3 2.1 Existing Site Conditions ................................ 3 2.2 Proposed Development ................................ 3 3.0 SCOPE OF INVESTIGATION ................................. 4 3.1 Site Reconnaissance .................................. 4 3.2 Field Exploration ..................................... 4 3.3 Laboratory Testing ................................... 4 3.4 Research, Analyses and Report .......................... 5 4.0 SITE GEOLOGY .......................................... 6 4.1 Earth Materials ...................................... 6 4.1.1 Pauba Formation (Map Symbol Tp) .................. 6 4.1.2 Old Alluvium (Map Symbol Qoal) ............... 6 4.1.3 Young Alluvium (Map Symbol Qal) .................. 7 4.1.4 Colluvium (Map Symbol Ocol) ...................... 7 4.1.5 Artificial Fill (Map Symbol Af) ....................... 7 4.2 Faulting ........................................... 7 4.3 Seismicity .......................................... 9 4.4 Groundwater ....................................... 10 4.5 ' ........... Subsurface Variations ...................... 10 5.0 CONCLUSIONS AND TRACT DEVELOPMENT CONSIDERATIONS ..... 12 6.0 EARTHWORK/SITE GRADING RECOMMENDATIONS .............. 13 6.1 General ........................................... 13 6.2 Liquefaction Potential ................................. 13 6.3 Removals/Overexcavation .............................. 14 6.4 Excavatability ....................................... 15 6.5 Subdrains .......................................... 16 6.6 Expansion Potential .................................. 16 6.7 Transition Lots ...................................... 16 6.8 Permanent Cut Slopes ................................ 17 89-81-165-01 Converse Consultants Inland Empire n LJ Table of Contents (continued) Page 6.9 Permanent Fill Slopes ................................. 17 6.10 Fill-Over-Cut Slopes .................................. 18 6.11 Stabilization Fills ..................................... 18 6.12 Oversize Material .................................... 19 6.13 Temporary Sloped Excavations .......................... 19 6.14 Utility Trench Backfill .................................. 20 6.15 Shrinkage and Subsidence ............................. 20 6.16 Site Drainage ....................................... 21 6.17 Slope Protection and Maintenance ....................... 22 6.18 Asphalt Pavements ................................... 23 7.0 STRUCTURAL DESIGN RECOMMENDATIONS ................... 24 7.1 Residential Foundation Design Criteria ..................... 24 7.2 Retaining Walls ...................................... 25 7.3 Slabs-on-Grade ...............:..................... 25 7.4 Appurtenant Facilities ................................. 26 7.5 Soil Corrosivity ...................................... 26 8.0 GEOTECHNICAL SERVICES DURING CONSTRUCTION .............. 27 9.0 CLOSURE ................................................ 28 REFERENCES DRAWING 1 GEOLOGIC MAP (in pocket) DRAWING 2 GEOLOGIC-CROSS SECTIONS A-A' DRAWING 3 GEOLOGIC-CROSS SECTION B-B' DRAWING 4 GEOLOGIC-CROSS SECTION C-C' APPENDIX A -FIELD EXPLORATION APPENDIX B -LABORATORY TEST PROGRAM APPENDIX C -STABILITY ANALYSES APPENDIX D -RECOMMENDED EARTHWORK SPECIFICATIONS APPENDIX E -STATISTICAL SEISMIC RISK EVALUATION 89-81-165-01 Converse Consultants Inland Empire ® PROFESSIONAL REGISTRATION CCIE Project No. 89-81-165-01 June 1, 1990 This report has been prepared by the staff of Converse Consultants Inland Empire under the professional direction of the Principal Engineering Geologists and Principal Engineers whose seals and signatures appear hereon. The findings, recommendations, specifications or professional opinions are presented, within the limits prescribed by the client, after being prepared in accordance with generally accepted professional engineering and geologic principles and practice in this area, at this time. There is no other warranty either express or implied. wEESSt p,~A, .~ ,w2~ `~v cyt c., ,~. ~ '-,: Cq 5T. ~ Nn. GE00~3A9 j,'_ OF C•A~~~ o-z--- C Quazi S.E. Hashm% Ph.D. Steven C. Helfrich Senior Staff Engineer Principal Engineer ~~ED 6f0C ~ c. -n v .~ ' [ r. ~ ~ G'O~G61:iT • c pF• ~ c - %~c~.~ C. ~dci,~ ~" ® Deems C. Padgett Greg ry . Rz a, CEG 1191 Senior Staff Geologist Princlpal Engi Bering Geologist Converse Consultants Inland Empire 1.0 INTRODUCTION C, This report presents the findings and conclusions of our geotechnical investigation for Tentative Tracts 25213, 25214 and 25215 designated as the Campos Verdes residential development in Temecula, California. The irregularly shaped, 166-acre site is located east of Winchester Aoad (Highway 79). The site is bounded on the south by unimproved Margarita Road, to the west by Winchester Road and an existing housing tract, to the north by scattered residential homes, and to the east by undeveloped property. The Site Location Map, Figure 1, shows the site location with respect to nearby streets and topographic features. The purpose of this investigation was to evaluate subsurface conditions and pertinent engineering properties of the encountered materials and provide recommendations regarding general site grading, slope stability and preliminary foundation design. Additionally, aerial photographs and pertinent geologic literature were reviewed to ® determine the presence of faults. Based on our aerial photograph review, site mapping and geologic observations, no faults project toward or through the site. It is our opinion, fault trenching is not warranted as a part of this study. It is our understanding that development of the 166-acre property will involve construction of 205 residential lots, 9mass-graded parcels and associated streets and landscaping. Pertinent geologic and geotechnical data generated from this investigation together with the location of the exploratory excavations are shown on Drawing 1, Geologic Map (pocket). Converse Consultants Inland Empire G C O V_ a 0 `o a w 0 a REFERENCE: Portion of Alquiet-Priolo Specfel Studley Zone, Murriette Cuadrengle, 1990 D 100D 2000 4000 SCALE IN FEET SITE L.OCA1'IO1~I 1~AP CAMPOS V.ERDES RESIDENTIAL DEVELOPMENT Pro~eci No. Temecula, California 89-81-16 for: Mesa Homes ~® Figure No. Converse Consu~tan4s @n9en~ Eea~~3re r L 2.0 PROJECT DESCRIPTION 2.1 Existing Site Conditions In general, the Tentative Tracts are in a relatively native, undeveloped state. The irregularly shaped project site is located east of Winchester Road. Topographically, the site consists of low rolling hills and associated southwest-trending drainages with a maximum relief of about 100 feet. Site elevations range between approximately elevation 1,168 feet (Lot 22) and elevation 1,069 feet (southwest end of Parcel 7). Vegetation consists of a moderate growth of weeds, shrubs, and grasses. Several unimproved roads and trails traverse the site. 2.2 Proposed Develgpment Based upon the Rough Grading Plan, (scale 1" = 100'), provided by NBS/Cowry Associates, dated September, 1989, site earthwork at pad locations, exclusive of any potential overexcavations, is anticipated to consist of cuts on the order of 55 feet deep (Parcel 6), and fills on the order of 25 feet deep (Lot 113). \.. J As depicted on the grading plan (Drawing 1) 205 residential lots and 9mass-graded parcels are proposed. Fill slopes on the order of 35 feet in vertical height are proposed. Cut slopes will be on the order of 38 feet in vertical height. For the purposes of this report, it is assumed that the residential structures will consist of one to two-story wood frame single family homes with concrete slabs-on-grade. 89-81-165-01 3 Converse Consultants Inland Empire 3.0 SCOPE OF INVESTIGATION 3 1 Site Reconnaissance A CCIE geologist pertormed a site reconnaissance of the property for mapping of geologic units and pertinent suficial features (Drawing 1). Aerial photographs of the site vicinity were examined stereoscopically to assist the geologic reconnaissance. 3.2 Field Ex Iof,Lration A total of nine exploratory borings and sixteen exploratory trenches were excavated within the site boundaries. Borings were drilled using bucket-auger and hollow-stem auger drill rigs and trenches were excavated using grubber-tired backhoe. All excavations were visually logged by our field personnel who described the materials encountered in detail. Boring BH-1 was entered by a CCIE geologist who carefully observed and documented the exposed materials. Approximate locations of the subsurface explorations are shown on Drawing 1. Relatively undisturbed and bulk samples of representative materials encountered were obtained from the borings and trenches. A description of the field exploration and sampling program is presented in Appendix A, Field Exploration Program. 3.3 Laboratory Testing Samples were tested in the laboratory to aid in the classification and to determine certain engineering properties of the site soils and bedrock. These tests include: o dry unit weight and moisture content o maximum density and optimum moisture o direct shear strength o consolidation c soil corrosivity o grain-size analysis o R-value r U 89-81-165-01 4 Converse Consultants Inland Empire A description of the laboratory test methods and test results are presented in Appendix B, Laboratory Test Program. Moisture and density data are presented on the Boring and Trench Summary Sheets in Appendix A. 3.4 Research. Analy,~es and ReRort In addition to pertinent published geologic literature, unpublished geotechnical reports were also reviewed. In particular, Highland Geotechnical Consultants investigated this site as a part of their study; their report was dated February 13, 1989. Pertinent publications reviewed for this report are included in the list of references. This report was written to present the findings of this geotechnical investigation for the tentative tract, and to provide recommendations for the proposed development. Based upon the field and laboratory findings, slope stability analyses were pertormed and the results are presented in Appendix D. ~J 89-81-165-01 5 Converse Consultants Inland Empire 4.0 SITE GEOLOGY A general description of the subsurface conditions and various materials encountered at the site during field exploration is presented in this section, along with a discussion of site-specific geologic conditions. 4.1 Earth Materials The site is underlain by bedrock materials of the Pauba Formation and alluvium. These, in turn, are locally mantled by topsoil. Art~cial fill was observed near the northwest site perimeter. Areal distribution of the earth materials is shown on the geologic map (Drawing 1), and these materials are described below, from geologically oldest to youngest. 4.1.1 Pauba Formation (Map Symbol Tol: 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- formational unconformities. Sedimentary features characteristic of the depositional environment such as channel lag, scour and fill, and cross-bedding were observed in trench and boring exposures. Within the subject site, lithology of the Pauba Formation is highly variable, consisting of poorly bedded to massive, moderately to well consolidated, fine to coarse sandstones. The sandstones are alluvial channel-type deposits with lenses of gravelly sandstone, and interbeds of siltstone and silty claystone. Bedrock structure within the Pauba Formation can vary over a relatively short distance. Structural attitudes measured at the site indicate roughly horizontal bedding. 4.1.2 Old Alluvium ~MagS_ymbol Qoal): Old alluvium was encountered over much of the site and is commonly overlain by a variable thickness of alluvium or topsoil (see below). These materials were c{assified as silty and/or clayey sands. In 89-81-165-01 6 Converse Consultants Inland Empire general, the older alluvium was slightly moist to moist, medium dense, with numerous pinhole voids, decreasing with depth. The thickness of older alluvium ranged from about 2 to greater than 30 feet in BH-9. 4.1.3 Young Alluvium (Mag_Symbol Qall: Young Alluvium was encountered in active drainages throughout the sfte. These materials were field-classified as silty to clayey sands. Generally the near surface alluvium is dry to moist, loose, with numerous pinhole voids and organics. The alluvium was up to 10 feet thick in BH-6. 4.1.4 Colluvium (Map Symbol Qcol): Colluvium was generally limited to second or third-order drainage throughout the site. Colluvium soils were classified as silty sands and clayey sands. Colluvium was not encountered in subsurface excavations, but is estimated to be about 2 to 6 feet in thickness. 4.1.5 Art~cial Fill (Ma~Svmbol Afl: Artificial fill is present near the northwest site boundary where lt was placed to construct a small reservoir. The fill consists of silty and clayey sands and is approximately 8 feet in thickness. Evidence of past grading of fill placement was not evident elsewhere on the site. 4.2 Faulting There are no active faults or fault related photolineaments projecting through or towards the site based on our review of aerial photographs and pertinent geologic literature. The site is not situated within a currently designated State of Cal'Ifornia Alquist-Priolo Special Studies Zone. The nearest known active faun is the Wildomar Branch of the Elsinore Fault,.sltuated approximately 1 mile to the southwest of the project. The location of the site with respect to regional faults is shown on Figure 4.2. According to Uniform Building Code (1988 edition), the project area is included in Seismic ® Zone 4. This zone denotes that major damage corresponding to intensities VIII or higher 89-81-165-01 7 Converse Consultants Inland Empire ///~/ ~ ~ /,.GJ. ,~ ~ BRw._ i ~ 2 DSO,. ~ „Iry y P H , /G••F •••~~~ .\~~0 ~\~ ••CANL•G®PIADfVa14A '. 4V. I ~ ••• ~~ ~ RIVERSIDE M~D~No BEACH '~o,P~ ~•,~ ~.; :~ .111 ~~ ~~~~~ ~~ 9~ ONOFRE <r \ I Nlly6 r --` ~ cRF~:.~ i FAULT~~ ~.~ ~ ® ~ ~,irp _ ~PALPA SPRINGS \ ~:~~\ . ~, .. ,~ `~~ ~~ ~\ .~~ ~`- ~ c o~ ~o .~ .~ .~ GRAND® \\~~ ~. F \. ~. T O C O V 0 0 v u 0 0 REFERENCE: After Jennings, 1875, Feuit Map of Celifomla _~ 0 10 20 APPROX. SCALE IN MILES SCALE: 7:750,000 REGIONAL FAULT P~IAP CAMPOS VERDES RESIDENTIAL DEVELOPMENT Prolecl NO. Temecula, California 89-81-1~ for: Mesa Homes Coraveese ConsuB~~e~4s ~eoBa~e~e1 ~ev9~BP~ Figure No. 4.2 ® on the Modified Mercalli Intensity Scale can be expected. Zone 4 also includes those areas that lie within a zone of major (Richter magnitude greater than 7) historic earthquakes and high levels of recent seismicity. The maximum credible earthquake is the maximum seismic event a particular fault is theoretically capable of producing based upon existing geologic and seismologic evidence. The maximum credible event does not imply that an earthquake of that magnitude has or will occur along the particular fault, but simply implies that the potential for such an earthquake does exist. Maximum credible earthquakes and associated seismic parameters for faults within a 100-km (62 mile) radius of the site are summarized on Table 4.2, Summary of Seismic Characteristics of Regional Faults. The faults listed in Table 4.2 are considered active faults capable of generating significant ground motions at the site. TABLE 4.2 SUMMARY OF SEISMIC CHARACTERISTICS OF REGIONAL FAULTS ® HORIZONTAL GROUND NOTION PARAMETERS MINIMUM NAXIMUMa MAXIMUM PEAKb DURATIONc SITE CREDIBLE ROLK OF STRONG DISTANCE MAGNiTUOE ACCELERATION SHAKING FAULT mi EARTHQUAKE (a) (seconds) Elsinore (Yi ldomar Branch) 1 7.5 0.70 25 - 35 San Jacinto 19 7.5 0.26 23 - 32 Hhi ttier 29 7.5 0.79 23 - 30 San Andreas (South) 35 7.5 0.78 22 - 30 San Andreas (Central) _._ 40 8.25 _ . 0.24 18 - 25. a Fram Greensfelder (7974). b Fram Seed and Idriss (1982). c From Bolt (7973). 4.3. Seismicity The Campos Verdes Project is situated in a seismically active region. Earthquakes of low to high magnitude may occur within the Southern California region. As is the case for most areas of southern California, this site may be subjected to strong ground shaking resuking from earthquakes associated with nearby faults. C 89-81-165-01 9 Converse Consultants Inland Empire To evaluate potential ground shaking at the project site, a statistical recurrence or probability of occurrence of various levels of ground motion based on past seismic activity was determined, using available sources of earthquake data. The analysis estimates the ground acceleration level expected to occur, at a particular site, within a 100-year period. The results of the analyses are presented herein. Descriptions of the analyses are presented in Appendix E. Seismic risk analyses resuts are summarized on Figure 4.3 where the number of occurrences exceeding a particular level of acceleration are plotted against the maximum peak horizontal ground acceleration. The solid line shown on Figure 4.3 represents CCIE's judgment as to the occurrences of ground accelerations during an average 100-year period. Expected ground accelerations are 0.34g once on the average every 100 years, and 0.27g once on the average every 50 years. For building design, the above value could be reduced to 65°~ for repeatable high ground accelerations as defined by Ploessel-and Slosson (1974). 4.4 Groundwater Groundwater was encountered at a depth of about 27 feet in BH-5 and at a depth of about 23 feet in BH-7. Both of these borings were located in active drainage channels. Groundwater levels noted were within bedrocks of the Pauba Formation. No other evidence of seeps or springs was observed at the site. 4 5 Subsurface Variations Based on the results of our subsurface exploration and experience, variations in the continuity and nature of subsoil and bedrock deposits and subsurface conditions should be anticipated. Due to the nature and depositional characteristics of the materials at the site, care should be exercised in interpolating or extrapolating subsurface conditions between or beyond test borings and trenches. Variations in groundwater levels can be expected due to seasonal changes. 89-81-165-01 10 Converse Consultants Inland Empire _ 100.0 x m E Q z o ~, w' w U x w' w U Z w U U O w O m . w m z 10.C 1.( 0.1i I- ~ -- ~ ~ ~ ~ ---~ -- - I O _ , ~ __ ~ __~ i -® ~ - .. - - - -- __ ~ i r t © r n m. 0.01 ~ 0.1 0.2 0.3 0.4 0.5 0.6 0.7 MAXIMUM PEAK HORIZONTAL ROCK ACCELERATION Amax(g) EXPLAMATIOW OF DATA POIPoTS: ® Fault Model -geologic evidence ® Site Region 1 Jr Instrumental seismicity data (1934-1987) ~ ® Local Site° `^ O Site Region Historic seismicity data (1800-1933) ^ Local Site a 0 ~ Local Slte low number of occurancea, off Dlot i -.- - 1! I, 5.0 CONCLUSIONS AND TRACT DEVELOPMENT CONSIDERATIONS The results of this investigation indicate that the Tentative Tracts are suitable for their intended usage and may be developed as planned. As depicted on Drawing 1, lots with fill slopes of up to 35 feet in height are proposed, and lots which transition from cut to fill are also proposed. 'Of geotechnical concern for this project is the potential for differential settlement due to the variable fill thicknesses proposed to underlie the various pads. Fill below finish grade should be compacted to at least 90% of the ASTM D1557-78 maximum laboratory density. Much of the residential distress which occurs in hillside graded lots is due to changes in moisture in the fill mass. Landscape irrigation and surface drainage should be controlled and provided such that the fill mass does not become excessively moist or wet. Any appurtenant structures such as swimming pools, retaining walls, grade changes and/or landscaping irrigation systems should be designed such that these future improvements do not adversely affect the graded lot stability or drainage. Therefore, ft is strongly recommended that these improvements be reviewed by a CCIE Geotechnical Engineer and Certified Engineering Geologist. Currently, canyon subdrains are not envisioned. It is possible that conditions maybe exposed during grading that require subdrains. These tract development considerations are described further in the following sections. Design recommendations are presented below for earthwork/site grading and structural design (for the development proposed on Drawing 1). Recommendations for additional geotechnical services, to be performed after this report has been approved by appropriate governing agencies, are also provided. ° 89-81-165-01 12 n LJ Converse Consultants inland Empire 6.0 EARTHWORK/SITE GRADING RECOMMENDATIONS 6.1 General Site grading is expected to consist of cuts, removals and fill operations to prepare building pad areas. Cuts on the order of 55 feet in depth are proposed. Maximum fill heights are expected to be 35 feet with maximum fill thickness of about 25 feet. Grading is also expected to include backfill for utility trenches. Loosely backfilled exploratory trenches (see Drawing 1) located throughout the site and any existing undocumented fill will require overexcavation and recompaction prior to the placement of structural fills. Proposed fill should be placed in accordance with the recommendations presented in Appendix D, Recommended Earthwork Spec cations. Structural fill should be compacted to at least 90% relative compaction (ASTM D1557-78). To reduce the potential for differential settlement across cut/fill transition lots, overexcavation and recompaction should be done as discussed in Section 6.6. ® All fill should be properly benched into firm and unyielding native materials, which is expected to consist solely of dense older alluvium or the Pauba Formation. Grading recommendations for removals, subdrains, permanent slopes, temporary sloped excavations, utility trench backfill, and site drainage are presented below. Stability calculations for the anticipated slopes are presented in Appendix C, Stability Analyses. The calculations indicate a factor of safety in excess of 1.5 for both cut and fill slopes for surficial and deep-seated stability. 6.2 Liquefaction Potential Soil liquefaction occurs in submerged granular soils during or after strong ground shaking. It has been well documented that liquefaction due to seismic shaking occurs in granular soils. Several requirements for liquefaction to occur are as follows: 89-81-165-01 13 Converse Consultants Inlantl Empire ® soils must be submerged; ® soils must be primarily granular; ® ground shaking must be intense; and ® duration of shaking must be sufficient for the soils to lose shearing resistance. Soils with large fine contents (large amounts of silt or clay) generally do not liquefy during seismic events. Highly sensitive clays could be a possible exception; however, such clays were not observed on this sfte. The alluvial soils at the site consist primarily of clayey and silty sand with occasional layers of sand. The Pauba Formation bedrock consists of sandstone, claystone and siltstone. The sandstone generally has interbedded claystone and siltstone layers. Due to groundwater recharge from water usage (irrigation) at the proposed development, the water level may rise. It is assumed for our evaluation that a 10-foot rise in water level may occur. In boring BH-5, water will then extend into the alluvium soil consisting of fine-. grained silt, but in boring BH-7 it will still be confined within the bedrock. Based on the fine-grained-nature of the alluvial soil and bedrock encountered within the possible saturation zone and the relatively high in situ densities, it is our opinion that structures at this site will not likely experience settlement-induced distress caused by liquefaction in the event of an earthquake. 6 3 Removals/Overexcavation 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. Non-organic debris from site clearing may be hauled offsite or stockpiled for crushing and/or placement by approved methods in deeper fill areas. Complete removal of all alluvial and topsoil, and loose compressible low strength older alluvium, and/or disturbed bedrock will be necessary prior to placement of structural fills. Although not encountered in CCIE explorations, any existing fill should be excavated. Recommended removal depths are depicted on Drawing 1, and discussed below: 89-81-165-01 14 Converse Consultants Inland Empire • o Drainage Areas (Alluviuml: The loose to medium dense granular soils present within the drainage channels are considered unsuitable for support of the proposed fills. Removals will vary from about 4 to 6 feet. Clayey sand soils of relatively low density were encountered in TP-15 and B-8 located in the floodplain near the southern site boundary. Based on dry densities, below counts and visual examination of these clayey sands, we anticipate about 15 feet of removals for this area. Areal distribution of these soils is not known and careful monitoring will be required during grading to insure .removal of these unsuitable soils. o Side-Slo ep s and,~wales Older Alluviuml: Relatively dry to slightly moist, medium dense, porous, clayey sand older alluvial soils were observed along the lower slopes of hillsides throughout the site and within most drainage swales. The depth of removal and recompaction of these materials will vary from approximately 2 to 4 feet. Exploration Trenches: All exploratory trenches were loosely backfilled and 'rf not excavated during grading operations will require overexcavation and recompaction for support of new improvements. Approximate locations of the trenches are shown on Drawing 1. Localized areas of removals deeper than those documented may be encountered during grading. The bottom of the excavated areas must be observed by a CCIE representative prior to placement of new fill. Removal depths shown on Drawing 1 are general removal depth guidelines. Actual removal depths should be established by CCIE field observations and testing during grading. Soils removed during the overexcavation procedures may be utilized as compacted fill, provided they have been stripped of organics and other deleterious materials. All proposed fills should be placed on competent native materials as determined in the field by the soil consultant representative and in accordance with the specifications in Appendix D. 6.4 Excavatability Based on the findings of our subsurface exploration and on our experience in the general site vicinity, we anticipate easy to moderate excavation of the Pauba Formation bedrock with a D-9 CAT with a single or double shank ripper. n U 89-81-165-01 15 Converse Consultants Inland Empire 6.5 Subdrains Canyon subdrains are not called for by this report. Subdrains may be recommended, however, depending upon during-grading exposures. Subsequent to alluvial removals and prior to fill placement, 'rf required, subdrains should be installed at approved locations according to the details shown on Drawings D-ia and D-ib (Appendix D), 'Typical Canyon Subdrain Detail." The clean-out and subdrain area should be observed and approved by CCIE personnel prior to subdrain installation; subdrain installation may be modified based upon post-removal observations. All subdrain devices should be accurately surveyed for location, line and grade after installation and sufficient time should be allotted for the survey prior to placement of fill over subdrains. Subdrain locations should be shown. on the as-built grading plans. Discharge from subdrains should be directed to a suitable non-erosive drainage device. If the subdrain discharges into the storm drain, measures should be taken to prevent storm drain water from backing up into the subdrain. 6 6 Expansion Potential Fill soils derived from the onsite alluvium which will be placed in proposed building areas may have a moderate expansion potential 'If not adequately blended with the sandy bedrock materials. Clayey siltstone and silty claystone layers encountered within the Pauba Formation may have high expansion potentials. Such materials could be exposed at final pad grades. It is recommended that 'rf claystone is exposed at final grade (i.e., on cut lots), these materials be overexcavated 3 feet and replaced with non-expansive materials (see Drawing D-2 'Typical Transition Lot Detail"). For all lots, final foundation and slab recommendations should be based on tests taken within the near-surface subgrade soils and bedrock at the completion of rou h grading. 6.7 Transition Lots To reduce the potential for differential settlement across cut/fill transition lots, the entire cut portion of the lot should be overexcavated 3 feet below final grade and replaced with 89-81-165-01 16 Converse Consultants Inland Empire • compacted fill to finished grade, as shown on Drawing D-2. All fill should be properly benched into firm and unyielding bedrock of the Pauba Formation. 6.8 Permanent Cut Sloes .Maximum vertical height of proposed permanent cut slopes is about 38 feet. As shown in Appendix C, cut slopes in the encountered materials n~c t exceeding 40 feet in height and cut no steeper than 2:1 (fiorizontal:vertical) have a calculated factor of safety (FS) greater than 1.5. Cut slope ratios should not be steeper than 2:1 (horizontal:vertical). A primary concern for cut slopes on this site is the high potential for erosion of the sandy :,material, and the resultant surficial instability. Structures should be set back from slopes as shown on Figure 29-1 of the 1988 edition of the Uniform Building Code (UBC). Geologic observation of all cut slopes should be conducted during grading to observe ff any adversely oriented planes of weakness p.e. claystone or siltstone beds) are present. Accordingly, 'rf these materials are exposed in proposed cut slopes during grading and are found to be adversely oriented, stabilization buttresses or fills may be required. -" 6.9 Permanent Fill Sloes Proposed fill slopes should be constructed at slope ratios no steeper than 2:1 (horizontal:vertical). In addition to normal compaction procedures, fill slopes should be properly compacted out to the slope face. This may be achieved by either overbuilding fill slopes and cutting back to the compacted core, or by back-rolling of slopes with sheepsfoot rollers at frequent increments of 2 to 3 feet in fill elevation gain, or by other methods which have been shown to produce satisfactory results. Feathering of fill over the tops of slopes shall not be permitted. Where fills are to be placed on natural ground steeper than 5:1 (horizontal:vertical), compacted fill should be keyed and benched into firm material (i.e., Pauba Formation bedrock), as shown on Drawing D-3, "Fill-Over-Natural Slope." Other benches should be excavated into firm, competent material for a minimum width of 4 feet. Keyway and benches should be approved by CCIE prior to placement of fills. 89-81-165-01 1 ~ Converse Consultants Inland Empire , Fill slopes over 25 feet in vertical height and placed on low permeability natural ground steeper than 5:1 should be provided with at least one backdrain at the heel of the keyway. The backdrain should consist of a 4-inch-diameter (minimum) perforated pipe embedded in 3 cubic feet of gravel per linear foot of pipe, connected to anon-perforated outlet pipe, (as shown on the detail on Drawing D-4, "Drainage Blanket Detail"). Outlet pipes should be accurately surveyed for location, line and grade. Locations of outlets and backdrain pipes should be shown on the as-built grading plans. Sufficient time should be allotted for the survey location of the subdrains prior to placement of fill. Fill slopes greater than 30 feet in height should be terraced as recommended in Section 7012 of the Uniform Building Code (1988 Edition). Structures should be set back from graded slopes in accordance with Chapter 29 (UBC Figure 29-1) of the Uniform Building Code. 6.10 Fill-Over-Cut Slopes Where fill is proposed over cut slopes, fill should be benched and keyed into firm bedrock as discussed in Section 6.8, above, and illustrated on Drawing D-5, 'Typical Fill Above Cut Slope." As shown on Drawing D-4, where fill-over-cut slopes are greater than 25 feet in vertical height, a backdrain should be provided at the fill/cut boundary. The backdrain should consist of a 4-inch-diameter (minimum) perforated pipe embedded in 3 cubic feet of gravel per linear foot of pipe, connected to a non-perforated outlet pipe. backdrain and outlet pipes should be accurately surveyed for location, line and grade. Locations and outlets of backdrains should be shown on the as-built grading plans. Sufficient time should be allotted for the survey prior to placement of fill. 6.11 Stabilization Fills Our field investigation did not indicate any adversely oriented planes of weakness that may also act as subsurface moisture barriers and may require the construction of 89-81-165-01 18 Converse Consultants Inland Empire stabilization fills. Fnal verification of conditions should be determined during grading ® geologic observations. If required, stabilization fills should be constructed as shown on Drawing D-6, "Buttress or Stabilization Fill Detail." The stabilization fill should be constructed with a minimum key width of 15 feet and a minimum key depth of 2 feet, inclined at 2% into slope from toe to heel of keyway. Backdrains should be provided at the heel of the keyway every 30 feet vertically. Backdrains should be constructed as shown on Drawing D-6, and as discussed in Section 6.9. 6.12 Oversize Material _ Oversize material defined as rock or other irreducible material with a dimension greater than 6 inches, shall not be buried or placed in fills unless the location, materials and disposal methods are specifically approved by CCIE. A suggested disposal method is shown on Drawing D-7, "Rock Disposal Detail for Isolated Burial." Disposal operations for oversize materials shall be such that nesting of material does not occur, and such that the oversize material is completely surrounded by compacted fill. Oversize material shall not be placed within 10 feet vertically of finished grade, within 20 feet horizontally of a slope face, or within the range of future utilities or underground construction, unless specifically approved by CCIE. 6.13 Temporar~Sloped Excavations The use of sloped excavations may be applicable where plan dimensions for excavation "are not constrained by property lines, existing streets, or other structures. Where constraints exist, slot-cutting, temporary shoring or a combination of slopes and shoring may be required. Recommendations for shoring design or slot-cutting can be provided upon request. Based upon soils encountered in the explorations, it is our opinion that sloped temporary excavations may be made according to the slope ratios presented in the following table: n LJ 89-81-165-01 19 Converse Consultants Inland Empire TEMPORARY E%CAVATION SLOPES ttA%IHIp DEPTH OF d1T tU)l I1RA4 SLOPE RAT[0° (ft) (horizontaLvertical) 0 - 5 vertical to 1/2:1 0 - 15 1R:1 to 3/4:1 0 - 50 1 1/4:1 to 1 1/2:1 a Selection of tenQorery slope ratios should be made by the grading Contractor based on actual materiels encountered during excavation. Temporary back cuts for buttress or stabilization fills, 'lf required, should further be analyzed. Slope ratios given above are assumed to be uniform from top to toe of slope. Sandy surfaces exposed in sloped excavations should be kept moist but not saturated to retard ravelling 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 of the top of slope, or a distance of at least one-third the slope height, whichever is greater. 6.14 Utility Trench Backfill Buried utility conduits should be bedded and backfilled around the conduit in accordance with the project specifications. Onsite materials with sand equivalents greater than 30 may be flooded/jetted around large diameter pipelines, below the spring line. Care should be taken not to move or damage utilities during compaction operations. Where conduit underlies concrete slabs-on-grade and pavement is adjacent to the proposed structures, the remaining trench backfill above the conduit should be placed and compacted in accordance with Appendix D. 6.15 Shrinkage and Subsidence Based on our test results, shrinkage and subsidence are estimated as follows: 89-81-165-01 20 u Converse Consultants Inland Empire © Residual Soils and Alluvium: Alluvium is expected to shrink on an average of • approximately 12% by volume, with variations from 2%to 20% shrinkage by volume at various locations. Subsidence in ravines due to earthwork activities may range up to 0.2 foot. o Pauba (Bedrockl: Shallow porous Pauba bedrock may shrink from negligible to 10% by volume when properly recompacted. Porous, weathered Pauba is not anticipated to be thicker than 1 to 3 feet below the bedrock surface. An average value of 5% can be used for preliminary shrinkage calculations. Deeper, dense Pauba bedrock is expected to shrink less. Shrinkage ranging from negligible to 6°~ is anticipated in most of the dense Pauba bedrock. An average shrinkage of 3% by volume may be used to estimate shrinkage in the deeper bedrock. Subsidence of the exposed surface in deep cuts into the Pauba bedrock is expected to be negligible, exclusive of wet weather earthwork disturbance. Volume losses due to stripping of organics should be included during the calculations of earthwork quantities. These estimates are based upon the assumption that all removals and compaction are performed as recommended herein. Estimates provided above should be considered preliminary. Refined estimates can be provided by CCIE during • earthwork, based on exposed conditions, additional compaction curve data, arid field density test results. Considering the quantities of earthwork proposed, some shrinkage variability from ravine to ravine, and hill to hill should be anticipated. 6.16 Site DrainagQ Adequate positive drainage should be provided away from structures to prevent ponding and to reduce percolation of water into the foundation soils. We recommend that slopes for surface drainage be constructed at 2% to 4% in landscaped areas and 1% to 2% in paved areas. Planters and landscaped areas adjacent to the building perimeter should be designed to minimize water infiltration into the subgrade soils. Planters adjacent to foundations should have waterproofed walls and bottoms and should have a drainage system to conduct water to a collection point for disposal. To enhance the long-term performance of the building pad areas, it is recommended that gutters and downspouts be installed on the roof, and roof runoff and surface pad drainage be collected and directed to the street through non-erosive devices. 89-81-165-01 21 Converse Consultants Inland Empire Slope drainage devices should be constructed in accordance with Chapter 70 of the Uniform Building Code (1988 Edition). Lot drainage should preclude the possibility of flow over slope faces with the use of brow dtches, earth berms and other methods. 6 17 Slope Protection and Maintenance Proposed 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, slope maintenance can be provided along wlth normal care of the grounds and landscaping. Cost of maintenance is less expensive than repair resulting from neglect. Most hillside lot problems are associated with water. Either uncontrolled water from a broken pipe, excessive landscape watering, or exceptionally wet weather causes most damage. Drainage and erosion control should be provided for long-term slope stability and performance. It is important that the drainage patterns and slope protection provisions be established at the time of final grading and maintained throughout the life of the project. 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 clean of debris so that water will not overflow onto the slope, causing erosion. All subdrains should be kept open and clear of debris and soil which could block them. 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, which may be natural seeps or an indication of broken water or sewer lines, should be noted and brought to the attention of CCIE. 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. However, during the wet season, over-irrigation can cause ground cover to pull loose, which not only destroys the cover, 89-81-165-01 22 Converse Consultants Inland Empire but also results in serious erosion. We suggest that a professional landscape architect • be consulted for planting and irrigation recommendations. 6.18 AsohaR Pavements Asphalt pavement sections have been designed based on an R-value of 29. Final street structural sections should be provided by CCIE based on the actual R-values of the street subgrades after grading. Based upon the Assumed Traffic Indices (Tls) provided to us, either full-depth or composite asphalt and base pavement sections may be used as tabulated below: ASPHALT PAVEMENT SECTIONS ASSUMED SPHAL OVER RASE ULL DEPTH TRAFFIC INDEX BAS (tn) ASPHALT (tn) ASPHALT (in) 4 3.0 3.0 4.5 5 6.0 3.0 5.5 6 6.0 4.5 7.0 7 8.0 5.0 9.0 In areas to support asphaltic pavement, the subgrade should be recompacted to a depth ® of at least one foot below the final subgrade as recommended in Appendix D. At the time of placing pavements, the subgrade should be firm and unyielding during proof rolling, and be within 2% to 3°k of optimum moisture. All base material should be compacted to a minimum of 95% of the ASTM D1557-78 laboratory maximum dry density. Base course should consist of CALTRANS Class II aggregate base or equivalent. Placement of full-depth asphalt will require that the compacted subgrade soils provide competent support for paving equipment. Clean cohesionless sands are subject to yielding under rubber-tired and track loads from paving equipment. The paving contractor should confirm in writing the acceptability of the compacted subgrade prior to placement of full-depth asphaR pavement. n U 89-81-165-01 23 Converse Consultants Inland Empire 7.0 STRUCTURAL DESIGN RECOMMENDATIONS 7.1 Residential Foundation Design Criteria Conventional spread footings, founded in properly compacted structural fill may be used to support the proposed residences. Footings should be set back at least 5 feet or one-third the slope height, whichever is greater, from the top-of-slope or toe-of-slope. Alternatively, footings may be embedded such that there is adequate setback between footings and the face of slopes. In any case, footings should have a minimum embedment of 12 and 18 inches below lowest adjacent grade for one and two stories, respectively. Residential footings should have a minimum width of 12 inches. Footings for one- to two-story wood frame homes may be designed for an allowable bearing pressure of 1,500 pounds per square foot (psf). All continuous footings should be reinforced wkh at least #4 reinforcing bars top and bottom, along the full width of the footings to mitigate the potential for differential fill settlement. Additional reinforcement may be required by the project architect and/or design engineer. Structure settlement will be due to relatively light foundation loads, as well as long-term consolidation of fill soils and compressible native materials below the fill. Maximum anticipated structural load-induced settlements of continuous residential footings, designed as recommended above, are 1/2 inch or less. Compacted fills will settle depending on the fill thickness and future changes in the 'as-compacted" moisture conditions. Properly compacted fill can be expected to settle 1 /2% to 1% of the fill thickness if the soils are allowed to become soaked. These fill settlements should be considered in design. Resistance to lateral loads will be provided by friction acting at the base of the footings and by passive resistance against the side of footings. A coefficient of friction of 0.35 may be assumed with the dead load forces. An allowable passive earth pressure of 250 psf per foot of depth to a maximum value of 2,500 psf may be used for the sides of footings poured against compacted fill or bedrock. The allowable passive pressure may be increased 33% for lateral loading due to wind or seismic forces. 89-81-165-01 24 Converse Consultants Inland Empire ® Foundation setback should be provided as recommended in Figure No. 29-1 of the 1988 Edition of the Uniform Building Code. Where reduced foundation setback is required, CCIE can evaluate specific cases and provide appropriate geotechnical criteria for design. 7.2 Retaining Walls It is not known at this time 'rf any retaining walls are proposed at the site. If required, the 'retaining walls may be designed for an assumed earth pressure equivalent to that exerted by a fluid weighing not less than that shown in Table 7.2.1. TABLE 7.2.1 EQUIVALENT FLUID WEIGHT _ (ocf) SURFACE SLOPE OF IF CLEAN SAND AND/OR IF NATIVE SANDY RETAINED MATERIAL GRAVEL WITH (b = 38° SOILS ARE USED NOR120NTAL TO VERTICAL IS USED TO BACKFILL TO BACKFILL Level 30 40 5 to 1 32 42 4 to L 35 45 3 to 1 38 48 2 to 1 43 53 Any applicable construction surcharges should be added to the above pressures. At least 12 inches of granular material should be used in the backfill behind the walls and water pressure should not be permitted to build up behind retaining walls. Retaining walls should be provided with weep holes or backdrains. The upper 12 to 18 inches of the backfill must consist of impervious soil. 7.3 Slabs-on-Grade Conventional, minimum 4-inch-thick slabs-on-grade may be constructed for support of nominal ground floor live loads. All slab subgrades should be moisture conditioned and compacted as recommended in Appendix D. Care should be taken to avoid slab curling if slabs are poured in hot weather. A mix design should also be provided to reduce the potential for shrinkage cracks. Slabs should be designed and constructed as promulgated by the Portland Cement Association (PCA). If non-expansive soils are used in the upper 4 feet (Expansion Index less than 30), then the design engineer need not ® design the slabs for expansive soils. Reinforcement should be provided as recommended 89-81-165-01 25 Converse Consultants Inland Empire by the design engineer, and may include conventional, post-tensioned, orfiber-reinforced slabs. If amoisture-sensitive floor covering (such as vinyl tile) is used, slabs should be protected by a 6-mil-thick polyethylene vapor barrier. If the barrier is used, it should be protected with 2 inches of sand placed above and below to prevent punctures and to aid in the concrete curing process. Vapor barrier seams should be lapped a minimum 6 inches and sealed. 7.4 Aoourtenant Facilities It is anticipated that residential lots will be customized, including home additions and construction of garden walls, pools, landscape ponds, retaining walls, general regrading, and modifications of landscaping. Any of these modifications may adversely change the foundation conditions, lot stability, and/or adversely affect adjacent lots. It is therefore strongly recommended that proposed lot modifications be reviewed by CCIE or an experienced Geotechnical Engineer and/or Certified Engineering Geologist. All homeowners should be made aware of the need for geotechnical evaluation of proposed foundation, grading, irrigation, and/or landscape modifications. 7.5 Soil Corrosivity A bulk sample obtained from the exploration was tested for resistivity, pH, and soluble sulfate and chloride content. Relatively moderate sulfate concentration was measured, less than 50 parts per million (ppm), and therefore conventional Type 1 or II portland cements may be used. A low chloride content and low to moderate resistivity were also measured, which would indicate low corrosivity. Conventional corrosion mitigation measures are therefore appropriate, such as the following measures: o All steel and wire concrete reinforcement should have at least 3 inches of concrete cover. a Below grade ferrous metals should be given a high quality protective coating, such as 18-mil plastic tape, extruded polyethylene, coal tar enamel, or portland cement mortar. 89-81-165-01 26 Converse Consultants Inland Empire 8.0 GEOTECHNICAL SERVICES DURING CONSTRUCTION This report has been prepared to aid in evaluation of the site, to prepare site grading recommendations, and to assist in the design of the proposed structures. As indicated above, additional studies may be required for appurtenant structures. It is recommended that this office be provided the opportunity to review the final .grading plan, design drawings and spec cations to determine'rf the recommendations of this report have been properly implemented. Recommendations presented herein are predicated upon the assumption that continuous earthwork monitoring will be provided by CCIE. Removal excavation bottoms should be observed by a CCIE representative. Structural fill and backfill should be placed and compacted during observation and testing by this office. Footing excavations should be observed prior to placement of steel and concrete to confirm that the footings are founded on competent soil and the excavations are free of loose and disturbed materials. 89-81-165-01 27 Converse Consultants Inlantl Empire 9.0 CLOSURE The findings and recommendations of this report were prepared in accordance with generally accepted professional engineering and engineering geologic principles and practice in this area, at this time. 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. As the project evolves, our continued consultation and construction monitoring should be considered an extension of our investigation services performed to date. CCIE should review plans and specifications to check 'rf the recommendations presented herein have been appropriately interpreted, and that the design assumptions used in this investigation are valid. Where significant design changes occur, ft may be necessary that CCIE augment, or modify, the recommendations presented herein. Subsurface conditions may differ in some locations from those encountered in the explorations, and may require additional analyses and possibly modified recommendations. This report was written for Mesa Homes, and only for the proposed development described herein. We are not responsible for technical interpretations by others of our exploratory information which has not been described or documented in this report. Specific questions or interpretations concerning our findings and conclusions may require a written clarification to avoid future misunderstandings. 89-81-165-01 28 Converse Consultants Inland Empire REFERENCES u u 89-81-165-01 Converse Consultants Inland Empire REFERENCES t I'~1 LJ Alquist-Priolo Special Studies Zone Maps, 1990, Murrieta 7 1/2' quadrangle: California Division of Mines and Geology, Sacramento, California. Bolt, B.A., 1973, Duration of strong ground motion: Proceedings on Fifth World Conference on Earthquake Engineering, v. 2, no. 292, p. 10. Duncan, J.M., and Buchignani, A.L., 1975, An engineering manual for slope stability studies: University of California, Berkeley, Department of Civil Engineering. Eppley, R.A., 1966, Earthquake history of the United States, Part II: Coast and Geodetic Survey (ESSA) Bull. no. 41-1. Greensfelder, R., 1974, Maximum credible rock accelerations from earthquakes in California: CDMG, Map Sheet 23. Highland Geotechnical Consultants, 1989, Geotechnical feasibility investigation, 1050± Acres -Rancho California Commerce Center, Rancho California, Riverside County, California: Highland Geotechnical Consultants Report, February 13, 1989, job no. 08-6574-012-00-00, log no. 9-3016. Jennings, C.W., et al., 1975, Faun Map of California: California Division of Mines and Geology, California Geologic Data Map Series Map No. 1, Map Scale 1:750,000. Kennedy, M.P., 1977, Recency and character of faulting along the Elsinore Fault Zone in Southern Riverside County, California: CDMG Special Report. 131, p. 1-12. Marachi, N.D., and Dixon, S.J., 1972, A method for evaluation of seismicity: Proceedings of the International Conference on Microzonation, Seattle, 1972. Mualchin, L., and Jones, A.L., 1987, Peak acceleration from maximum credible earthquakes in California: CDMG Open File Report (in progress), p. 1-79. Ploessel, M.R., and Slosson, J.E., 1974, Repeatable high ground accelerations from earthquakes: California Geology, Sept. 1974, p. 195. Riverside County Flood Control District, 1962, Aerial photograph nos. 16 and 17, flight flown January 28, 1962, scale 1" =2000': Riverside County Flood Control District, Riverside, California. Seed, H.B., and Idriss, I.M., 1982, Ground motions and soil liquefaction during earthquakes: Earthquake Engineering Research Institute Monograph, p. 1-134. Uniform Building Code (UBC) 1988,: International Conference of Building Officials, Whittier, California. Wesnousky, S.G., 1986, Earthquakes, quaternary faults, and seismic hazards in California: Journal of Geophysical Research, no. B12, p. 12,587-12,631. 89-81-165-01 Converse Consultants Inland Empire DRAWINGS 89-81-165-01 Converse Consultants Inland Empire 0 APPENDIX A FIELD EXPLORATION ~o~ 89-81-165-01 Converse Consultants Inland Empire APPENDIX A FIELD EXPLORATION O Field exploration included a site reconnaissance and subsurface exploration program. During the site reconnaissance, surface conditions were noted, and the locations of test borings and trenches were determined. Exploratory borings and trenches were approximately located using existing boundary and other features as a guide. Elevations shown on the logs were interpolated from the site topographic map. - Exploratory borings were advanced using a 8-inch-diameter hollow-stem auger or a ' 24-inch-diameter bucket auger drilling equipment. Exploratory trenches were excavated by a backhoe equipped with a 24-inch bucket. Soils were continuously logged by experienced geologists, and classed in the field by visual examination in accordance with the Unified Soil Classification System. Where deemed appropriate, the exploratory -- borings and trenches were entered by a geologist who observed the exposed earth materials. Where appropriate, field descriptions and classifications have been modified to reflect laboratory test results. Relatively undisturbed samples and bulk samples of typical soil types were obtained. Relatively undisturbed samples of the subsurface materials were obtained at frequent O intervals in the exploratory borings. The relatively undisturbed samples were obtained using a steel drive sampler (2.4-inch inside diameter, 3-inch outside diameter) lined with sample rings. In bucket-auger borings, the steel sampler was driven into the bottom of the boreholes with successive drops (from a height of 12 inches) of the telescoping kelly bar. In hollow-stem auger borings, samples were driven by a 140-pound hammer dropping 30 inches. Depths below ground surface versus kelly bar weights are as follows: DEPTH BELOY KELLY BAR GRWNO SURFACE YEIGHT (ft) (oourds) 0 - 25 2,525 25 - 45 7,400 The number of successive drops of the driving weight ("blows") required for one foot of penetration of the sampler are shown on the Boring Summary Sheets (Drawings A-1 through A-9) in the "blows/foot" column. The soil was retained in brass rings (2.4 inches in diameter, 1 inch in height). The central portion of the sample was normally retained O and carefully sealed in waterproof plastic containers for shipment to the laboratory. 89-81-165-01 Converse Consultants Inland Empire A-2 Logs of the exploratory borings and trenches are presented in the following boring and O trench summary sheets which also include descriptions of the materials, pertinent field data and supplementary laboratory data. A key to soil symbols and terms is presented on the key sheet included as the last page in Appendix A. O O 89-81-165-01 Converse Consultants Inland Empire _ ... Log of Boring 1110. BH-Y Date Drilled: 4/4/90 Logged by: DCP Checked by: GFR ~quipment: Bucket Au>;er Driving Weight and Drop: 0-25~, 2525 Ib.; 25-45~, 1400 Ib. Ground Surface Elevation: 1168 feet Depth to Water: none encountered C C SUMMARY OF SUBSURFACE CONDITIONS S AMPLES ~ _ This log ie part of the report prepared by Converse far this project and F. '. ., 3 ?"+, should be read together with the report. This summary applies only at the O W F U location of the boring and at the time of drilling. Subsurface conditions LL ~ ~ M 2 may differ at othei locations and may change at this location with the j 3 N ~ 4 W F a passage of time. The data presented is a simplification oC actual conditions ~ y ? J O ~ u F W O ~ o O J encountered. O ~ m F a O ~+ O ..,._.. BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, massive, rootlets 9 7 126 throughout, dark brown SANDSTONE: fine grained, increased silt content, 6 14 112 massive, brown S ,;. _ _ _ ---------------- - - trace to fine to medium grained SANDSTONE: 6 4 98 10 -;. ~ , , little silt, massive, dull white _ = SANDSTONE: medium grained, silty, massive, = brown IS 20 - - increasing moisture S 3 98 ---------------------------------- 2S CLAYEY SII.TSTONE: thin interbeds of sandstone, green-gray --------------------------------------- SANDSTONE: fine grained, clayey, massive, dark - brown 30 : Approximate bedding at 25 feet: N62°E, 6°NW 5 II 124 Project No. Drawing No. Converse Consultants Inland Empire 89-81-165-01 P1-1 Log of Boring i\lo. BH-1 Date Drilled: 4/4/90 Logged by: DCP Checked by: GFR Equipment: Bucket Auer Driving Weight and Drop: 0-25~, 2525 Ib.; 25-45~, 1400 Ib. O Ground Surface Elevation: 1168 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ ~ ~ This log is part of the report prepared by Converoe for this project and should be read together with the report. This summary applies only at the h ,O .' . W 3 F U location of the boring and at the time of drilling. Subsurface conditions 0. ¢ H I w I may differ at other locations and may change at this location with the W \ N ~ ' F Z ~ .~ x ¢ a ¢ p passage o[ time. The data presented is a simplification of actual conditions H J O H } U = WO ~~ encountered. O m m E O a O End of boring at 35 feet No groundwater encountered No caving Boring backfilled and tamped on 4/4/90 C Project No. Drawing No. Converse Consultants Inland Empire 89-81-165-01 ~-1 Log of Boring illo. BH-2 - Date Drilled: 4/4/90 Logged by: DCP Checked by: GFR ~quipment: 8" follow Stem Auer Driving Weigh[ and Drop: 140 Ib / 30 iv Ground Surface Elevation: 1158 feet Depth to Water: none encountered C C SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ ~ +~ .'`. F a WO U N R ¢ p - ~~ This log ie pazt of the report prepared by Converse for this project and should be read together with the report. This summary applies only at khe 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. j M O Y J m F O LL \ 3 O f0 ,' , ¢ ~ N N E 3 F+ Z O 4 > n O a W = O TOPSOIL -CLAYEY SAND (SC), fine grained sand, -_ trace gravel, rootlets throughout, abundant pin-hole - voids, angular fragments of siltstone, dark brown 48 7 114 _. BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, brown 5 70/9" 12 118 - 0/10' 6 119 ]0 _ decreasing silt content well rounded gravel 15 - 20 25 medium grained sandstone interbeds 64 6 111 - 30 •. . --------------------------------------- CLAYEY SILTSTONE: micaceous, bedded, green-gray, Thin interbeds of sandstone 24 16 106 Project No. Drawing No. Converse Consultants Inland Empire 89-81-165-01 ~-2 Log of Boring iUo. BH-2 Date Drilled: 4/4/90 Logged by: DCP Checked by: GFR Equipment: 8" Hollow Stem Aut;er Driving Weigh[ and Drop: 140 lb / 30 in O Ground Surface Elevation: 1158 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ This log ie part of the report prepared by Converse for this project and F ', , 3 +~ should be read together with the report. This summary applies only at the O .'`. U location of the boring and at the Lime of drilling. Subsurface conditions LL ~ t+ _ H = may differ at other locations and may change at this location with the j 3 ~ = W a ¢ p passage of time. The data presented is a simplification of actual conditions ~ y j J I !1 4 (C d F O p J encountered. O m m O E ^ ~ O End of boring at 35 feet No groundwater encountered Boring backfilled on 4/9/90 Converse Consultants Inland Empire Project No. 89-81-165-O1 Drawing No. A-2 J Log of Boring silo. 8H-3 Date Drilled: 4/9/90 Logged by: DCP Checked by: GFR ~quipment: 8" Hollow Stem Auer Driving Weight and Drop: 140 lb / 30 in Ground Surface Elevation: 1155 feet Depth to Water. none encountered C C SUMMARY OF SUBSURFACE CONDITIONS snnptes This log is part of the report prepared by Converse for this projeck and t. ~ 3 +~ should be read together with the report. This summary applies only at the °o w r v U location o[ khe boring and at the time of drilling. Subeur[ace conditions LL j = ~ M may differ at other locations and may change at Lhis location with the j 3 N U 4 W F a p passage of time. The data presented is a simplification of actual conditions ~ Y 7 J o } a F W O ~ 0 C7 J encountered. O m m ~ ~ O ~+ O .,..,..:: BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, dark brown 42 9 106 5 44 5 122 SANDSTONE: medium to coarse grained, less silt, _ - dull white to light brown 43 2 102 10 IS - ^„ CLAYEY SII.TSTONE: minor fine grained 28 22 98 20 sandstone interbeds, green-gray 25 0/11' 13 106 30 Converse Consultants Inland Empire Project No. 89-81-165-01 Drawing No. A-3 Log of Boring silo. BH-3 Date Drilled: 4/9/90 Logged by: DCP Checked by: GFR Equipment: 8" Hollow Stem Auer Driving Weigh[ and Drop: 140 Ib / 30 in O Ground Surface Elevation: 1155 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ This log ie part of the report prepared by Converse Cor this project and ~ ', , 3 +' w should be read together with the report. This summary applies only at the O LL v U location of the boring and at the time of drilling. Subsurface conditions \ ¢ O ~+ Z ~ H f+ d may differ at other Ibcations and may change at this location with the 7 3 U~I O 4 W p passage of time. The data presented is a simplification of actual conditions H Y J O t• } U 2 W ^ ~ 0 p J~ encountered. O m m E O a O BEDROCK - PAUBA FORMATION (Qp) CLAYEY SILTSTONE (continued) 21 13 118 40 End of boring at 40 feet No groundwater encountered Boring backfilled 4/9/90 Converse Consultants Inland Empire Project No. 89-81-165-01 Drawing No. A-3 Log of Boring iVo. BH-4 Date Drilled: 4/9/90 Logged by: DCP Checked by: GFR ~quipmen[: 8" Hollow Stem Auer Driving Weight and Drop: 140 Ib / 30 in C C Ground Surface Elevation: 1080 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ This log is part oC the report prepared by Convene for this project and F ' , j +' '` should be read together with the report. This eummary applies only at the LL ~ H . . U location of the boring and at the time of drilling. Subsurface conditions \ ~ Z ~ ~ ,.i a may differ at other locations and may change at this location with the j Y 3 N O 4 W a Q p passage of time. The data presented is a simplification of actual conditions iy J O H Y u 2 O p J encountered. O m m E O a O ALLUVIUM (Qal) -SILTY SAND (SM): fine grained, abundant rootlets and pin-hole voids, loose, brown 70 22 105 ___ -------------------------------- SAND (SP): fine to medium grained, trace silt, IS 5 brown no recovery of drive sample 22 10 CLAYEY SAND (SM): fine to medium grained, dark brown 23 IS ' BEDROCK - PAUBA FORMATION (Qp) 26 18 108 20 - _ SANDSTONE: fine grained, clayey, massive _- appearance, local medium grained interbeds, gray-green 39 16 115 25 - clean medium grained sandstone interbeds - 58 16 110 30 End of boring at 30 feet No groundwater encountered Boring backfilled on 4/9/90 Converse Consultanes Inland Empire Projetk No. 89-81-165-01 Drawing No. A-4 Log of Boring filo. 13H-5 Date Drilled: _ 4/9/90 Logged by: DCP Checked by: GFR Equipment: S" Hollow Stem Auer Driving Weight and Drop: 140 Ib 1 30 in O Ground Surface Elevation: 1073 feet Depth to Water: 27.3 feet SUMMARY OF SUBSURFACE CONDITIONS S AMPLES ~ _ Thie log is part of the report prepared by Converse for this project and G ,' ~ 3 +~ ~ should be read together with the report. This summary applies only at the . + U location o[ the boring and at the time of drilling. Subeur[ace conditions LL j Z x 2 M 2 may differ at other locations and may Change at Chia location with the j x ~ 3 U~1 = ~ W a ¢ p passage of time. The data presented is a simplification o[ actual conditions w ^ ~ O OJ encountered. O m m ~ O a O ALLUVIUM (Qal) -SILTY SAND (SM): fine grained, rootlets and pin-hole voids to about 3 feet, light brown 27 9 112 ___ SAND (SP): fine to medium grained, light brown 14 5 33 13 121 10 .wet layers of medium grained sand 10 15 ___ - ---------------------------- SII,T (ML): clayey, possibly tipper weathered bedrock, gray-green 17 14 116 20 BEDROCK - PAUBA FORMATION (Qp) SANDSTONEJSILT$TONE: interbedded, clayey, fine ~ to medium grained sandstone, brown and gray-green 41 18 107 25 ' - s , SANDSTONE: fine grained, increased moisture, mottled gray and brown 41 30 90 30 End of boring at 30 Feet Let boring stabilize 7 minutes; groundwater at 27.3 feet Boring backfilled on 4/9/90 ~~ Project lYO. urawmg no. ~,~j--, Converse Consultants Inland Empire H4_gl_16s_ol PL-5 Log of Boring I~lo. BH-6 ~_. Date Drilled: 4/9/90 Logged by: DCP Checked by: GFR ~quipment: 8" Hollow Stem Auer Driving Weight and Drop: 140 lb / 30 in C C Ground Surface Elevation: 1099 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES This log is pazt of khe report prepared by Converse for Chia project and F- ~ 3 ~ should be read together with the report. This summary applies only at the O W F ~+ U location of the boring and at the time of drilling. Subsurface conditions LL \ ¢ 7 H Z e 2 ~y 2 may differ at other locations and may change at khis location with the W al F 7 .. ~ R ¢ O pmsage of time. The data presented is a simplification of actual conditions H j O tNi > U Z ~ ~ J encountered. p m m E O ~' O ALLUVIUM (Qal) -SILTY SAND (SM): fine grained sand, abundant voids to 4 feet, dark brown 61 5 113 33 5 layers of clayey sand 56 10 117 10 --- OLD ALLUVIUM (goal) - SII,TY SAND~(SM) 19 15 -- BEDROCK - PAUBA FORMATION (QP) _ SANDSTONE: fine to medium grained, silty, brown. Local interbeds of green clayey siltstone - 63 10 123 20 medium grained gravelly interbeds - 0/]0' 8 85 25 End of boring at 25 feet No groundwater encountered I Boring backfilled 4/9/90 Project No. Drawing No. Converse Consultan¢s Inland Empire 89-81-165-01 ~-6 Log of Boring IVo. BH-7 Date Drilled: 4/9/90 Logged by: DCP Checked by: GFR Equipment: 8" Hollow Stem Auer Driving Weight and Drop: 140 Ib / 30 in O Ground Surface Elevation: 1080 feet Depth to Water: 22.8 feet SUMMARY OF SUBSURFACE CONDITIONS SAM7LES This log ie part of the report prepared by Converse for this project and F ~ 3 +i should be read together with Lhe report. This summary applies only at the O W H V U location of the boring and at the time of drilling. Subsurface conditions 1\L 7 Z ~ M a may differ at other locations and may change at this location with the j 3 N O w W U ¢ p passage of time. The data presented is a eimplif cation o[ actual conditions H Y J O H > U S . ~ ~O J encountered. O m m F O a O ALLUVIUM (Qal) -SILTY SAND (SM): fine grained sand, rootlets and pin-hole voids to 3 feet, dark brown 58 7 106 20 5 OLD ALLUVIUM (goal) -SAND (SP): fine to medium 13 10 ] 17 10 grained, locally silty, brown BEDROCK - PAUBA FORMATION (Qp) - SANDSTONE: fine to medium grained, silty, trace gravel, brown 79 7 112 IS 20 ___ ----------------------- ------- SII.TSTONE: micaceous (about 90% mica), trace fine grained sand, increased moisture, silvery brown Y 31 13 114 25 End of boring at 25 feet Let boring stabilize 8 minutes; groundwater at 22.8 feet Boring backfilled 4/9/90 Converse Consuleanes Inland Empire Project No. 89-81-165-01 Drawing No. A-7 Log of Boring Itlo. BH-8 Date Drilled: 4/25/90 Logged by: DCP Checked by: GFR ~quipment: 8" Hollow Stem Auer Driving Weight and Drop: 140 Ib / 18 in Ground Surface Elevation: 1079 feet Dep[h to Water: none encountered C C SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ ~ This log ie part of the report prepared by Converee for this project and F- ( , 3 +~ should be read together with the report. This summary applies only at Lhe U location of the boring and at the time of drilling. Subsurface conditions W \ ¢ 7 ~+ Z 2 H 2 may differ at other locations and may change at Chia location with the W N r 7 ~ ¢ a ¢ p passage of time. The data presented is a simplification of actual canditiona w J O H > U 2 O p J encountered. O m m L O~ O OLD ALLUVIUM (goal) -SILTY SAND (SM): fine to medium sand, rootlets and organics upper 4 feet, brown 34 3 111 5 no recovery of drive sample 25 10 CLAYEY SAND (SC), medium grained sand, dark 14 ~~ brown ~ fi d k b 26 25 100 rown ~ ne sand, ar SILT (ML): clayey, trace 15 CLAYEY SAND (SC): medium grained sand, brown ----------------------- ---------------- SAND (SP): medium to coarse grained sand, brown 39 4 103 20 CLAYEY SAND (SC): fine to medium sand, brown 39 16 I10 25 End of boring a[ 25 feet No groundwater encountered Boring backfilled 4/24/90 Project No. Drawing No. C~~ Converse Consultants Inland Empire 89-81-165-01 Q-8 Log of Boring No. BH-9 Date Drilled: 4/24/90 Logged by: DCP Checked by: GFR Equipment: 8" Hollow Stem Auer Driving Weigh[ and Drop: 140 Ib / 18 in ~ O Ground Surface Elevation: 1096 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ This log is part of the report prepared by Converoe for Chia project and 1,. ,' , 3 +~ should be read together with the report. This summary applies only at the LL ~ H v U location of the boring and at khe time of drilling. Subsurface conditions \ 7 Z x i..i may differ at other locations and may change at this location with the 7 3 N ~ W r a passage of time. The data presented ie a aimpli~cation of actual conditions ~ y j J 4 ¢ d f W O ~ o O J encountered. O m m O E O ~ O OLD ALLUVIUM (goal) -CLAYEY SAND (SC)/SII,TY SAND ($M): interbedded, fine grained sand, abundant rootlets and organics to about 7 feet, pin-hole voids to about 5 feet, voids decrease with depth, dark brown 42 7 112 5 29 7 111 10 SILTY SAND (SM): fine grained sand, brown 28 11 116 15 - - - - - sand T~Fown (SP) inefTium to coarse giatned SAND 53 5 109 20 --------------------------------- SILTY SAND (SM): fine to medium grained sand, brown 25 ------------------------------------ - 32 16 108 - - 30 SILT (ML): clayey, trace fine grained sand, brown End of boring at 30 feet No groundwater encountered Boring backfilled 4/24/90 j~~\ Project No. Drawing No. Converse Consultants Inland Empire 89-81-165-01 ~- 9 Log of Test Pit iVo. TP-1 .. Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR ~quipment: Backhae Driving Weight and Drop: C Ground Surface Elevation: 1130 feet Depth to Wa[er: none encountered Project No. Drawing No. i~,~j-7-, Converse Consultants Inland Empire g9-g1-165-01 A-10 SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ This log ie part of the report prepared by Convene for this project and o ', , 3 +~ ~ should be read together with the report. Thia eummary applies only at the . . U location of the teat pit and at the time of drilling. Subsurface conditions 1\L 7 = ~ I M S may differ at other locations and may change at this location with the j 3 N 7 4 W a ¢ p passage o[ time. The data presented is a simplification of actual conditions w Y J O N > U = W p ~ O pJ encountered. K O 7 m J m O L U: d O~ F- O TOPSOIL -CLAYEY SAND (SC): fine grained sand, dry, medium dense, rootlets and open voids dark brown th hout - roug , -:: BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine to medium grained, silty, 5 - rootlets and pin-hole voids to 3 feet, massive, dry, - moderately hard, brown End of test pit at 7 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1'=s' cH=v1 SKETCH a -: sao°E k Y- y _ ', >, ~- \,-- • • Q '~:_ _ Log of Test Pit iVo. TP-2 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR Equipment: Backhoe Driving Weight and Drop: O Ground Surface Elevation: 1117 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ This log is part of the report prepared by Converse for this project and F- ', , 3 +~ should be read together with the report. This summary applies only aL Lhe O ¢ ~ U location of the teat pit and at the time oC drilling. Subsurface conditions I L \ 7 t i Z x ~..i 2 may di[fer at other locations and may change at this location with the W N F O ~ ¢ F a p passage of time. The data presented ie a simplification of actual conditions ~ j ~ ¢ 6 F W O ~ 0 O J encountered. O m m O E O ~ O TOPSOII. -CLAYEY SAND (SC):, fine grained sand, rootlets and open voids throughout, dry, moderately - dense, dark brown _ BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, highly weathered 5 with open voids and rootlets to 2.5 feet, carbonate along random fractures, massive, dry, moderately hard, brown End of test pit at 7 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1'=5' (H=V) SKETCH ~-: N45'E i` r ~psoil ~ _ ~ • ' y.._7 '. ~ QP YrolecL No. Uraw~ng hO. Converse Consultants Inland Empire 89-81-165-O1 A-11 Log of Test Pit fl1o. TP-3 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR ~quipment: Backhoe Driving Weight and Drop: C C Ground Surface Elevation: 1073 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ _ Thie log ie part of the report prepared by Converse for this project and F '. , 3 +~ should be read together with the report. This summary applies only at the O LLl F- v U location of the teat pit and at the time o[ drilling. Subsurface conditions LL ~ '+ I w 2 may differ at other locations and may change at this location with the j 3 N ~ W a ¢ C7 passage oC time. The data presented ie a simplification of actual conditions H Y J O H w > tl 2 LLI ^ ~ O OJ encountered. p m m F O¢ O - 6 inches of TOPSOIL . - :: OLD ALLUVIUM (goal) -CLAYEY SAND (SC} fine - grained sand, trace gravel, rootlets to 1.5 feet, dry, very dense, brown Lower 3 feet of test pit exposes reworked sandstone 5 bedrock Refusal at 6 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1 '=s• cH=vl SKETCH ~ -: N88°E ' y-- To soil ~ ~ ~-- ~- . _ ~ ~ ~x . Qoal Converse Consultants Inland Empire Project No. 89-81-165-01 Urawmg No. A-12 Log of Test Pit IUo. TP-4 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR Equipment: Backhoe Driving Weight and Drop: O Ground Surface Elevation: 1145 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES Thia log is part of the report prepared by Convene for this project and F ~ 3 ~ should be read together with the report. This summary applies only at the O w H U location of the keet pit and at the time of drilling. Subsurface conditions w \ ~ 7 ~+ Z ~ 2 H S may differ at other locations and may change at this location with the W N F 7 ~ ~ ~a a p passage of time. The data presented is a eimplilication of actual conditions H J O H Y U S ~ Q~ encountered. p m m E O a O TOPSOIL -CLAYEY SAND (SC): fine grained sand, -_ rootlets and open voids throughout, dry, loose, dark brown - ° BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, weathered with open voids and rootlets to 2 feet, massive, dry, hard, brown End of test pit at 4 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1 '=s• ttt=v> SKETCH a Ns°E '- T ~__ T i~psoil •~ _>>~ ~Qp Converse Consultants Inland Empire Project No. 89-81-165-01 Drawing No. A-13 Log of Test Pit fllo. TP-5 Date Drilled: 4/10/90 ~quipment: Backhoe Ground Surface Elevation: 1117 feet C C Logged by: DCP Checked by: GFR Driving Weight and Drop: Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ This log ie part of the report prepared by Convene for Chia project and F ', , 3 +~ should be read together with the report. This summary applies only at the LL ~ ~ t) location of the teat pit and at the time of drilling. Subsurface conditions \ 7 Z x = ~y S may ditfer at other locations and may change at this location with the W N r 7 ~ ¢ a a p passage of time. The data presented is a simplification oC actual condition s H J O N T U 2 ~ ~~ encountered. O m m E O a O ALLUVIUM -SAND (SP): fine grained sand, rootlets throughout, dry, loose, light brown "~""`:: BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, minor pin-hole voids throughout, slightly weathered, dry, moderately hard, brown End of test pit at 4.5 No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1•=s• ctt=v) SKETCH a- : S75°w Qa1 ' . .. ~ QP Converse Consultants Inland Empire Project No. Drawing No. 89-81-165-O1 Q-1~ Log of Test Pit silo. TP-6 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR Equipment: Backhoe Driving Weight and Drop: O Ground Surface Elevation: 1143 feet Depth to Water: none encountered ' SUMMARY OF SUBSURFACE CONDITIONS SAMPLES This log is part of the report prepared by Converse for this project and ~ ~ 3 +~ should be read together with the report. This summary applies only at the O .~`. U location of the teat pit and ak the time of drilling. Subeurfaee conditions ~ j Z F w a may differ at other locations and may change at thin location with Lhe j 3 N ~ ~ W a ¢ p passage of time. The data presented ie a simplification of actual conditions w y J O H . ) u = ~ ~~ encountered. O m m E D a O OLD ALLUVIUM (goal)- SII.TY SAND (SM): fine grained sand, rootlets and open voids, dry, loose, light brown ' CLAYEY SAND (SC): fine to medium grained , open voids throughout, moist, medium dense, dark brown BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: medium grained, slightly weathered, massive, dry, moderately hard, brown End of test pit at 4 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1'=s• IH=v> SKETCH ~--: sus°w Q . al ~ . • •Q ~- ~ . Converse Consultants Inland Empire Project No. 89-81-165-01 llrawing No. A-15 l Log of Test Pie ~o. TP-7 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR ~quipment: Backhoe Driving Weight and Drop: C C Ground Surface Elevation: 1095 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ This log ie part of the report prepared by Converse for this project and F ', , 3 +~ ~ should be read together with the report. This summary applies only at the . . U location of the teak pit and at Lhe time of drilling. Subsurface conditions LL ¢ H S H t may differ at other locations and may change at this location with the W N r ~ ~ ~ a a p passage of time. The data presented ie a simplification of actual conditions H j p H y ~ 2 W ^ ~ O p J encountered. ~ ^ ^ m J [9 O E R d ^~ H O OLD ALLUVIUM (goal) -SILTY SAND (SM): fine grained, minor roots, dry, loose, light brown CLAYEY SAND (SC): fine to medium grained sand, pin-hole voids to about 3 feet, very moist to 5 feet,, slightly.moist to 11 feet, medium dense, dark brown 5 ]0 - P I SANDSTONE: fine to medium grained, silty, slightly -_ weathered, micaceous, massive, moist, soft fo - brown moderately hard , End of test pit at 14 feet No caving No roundwater encountered Test pit backfilled 4/10/90 SCALE: t•=s' cH=v) SKETCH a--: N1°w - ~_ , Qoal ~ QP.. Converse Consuleanes Inland Empire Project No. 89-81-165-01 Drawing No. A-16 Log of Tese Pie I\!o. TP-8 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR Equipment: Backhoe Driving Weight and Drop: O Ground Surface Elevation: 1109 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ This log is part oC khe report prepared by Convene for this project and F , , 3 +~ ~` should be read together with the report. This summary applies only ak the O W F . . U location of the teat pit and at the time o[ drilling. Subsurface conditions W ~ ~"~ 2 M 2 may difter at other locations and may change at this location with the w QI F 7 .. ~ a ¢ O passage o[ time. The data presented ie a simplification of actual conditions H j p w Y U 2 w0 ~~ encounkered. -' O m m E O a O OLD ALLUVIUM (goal) -CLAYEY SAND (SC): fine grained sand, pin-hole voids to about 3 feet, minor rootlets, moist, medium dense, dark brown 5 _': BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, unweathered, soft to moderately hard, brown slightly moist massive , , End of test pit at 8 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1•=s' cH=v1 SKETCH a--: N5°E oal QP. .. Converse Consuleanes Inland Empire Project No. 89-81-165-01 1lrawing N0. A-17 l J Log of Test Pit i1lo. TP-9 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR ~quipment: Backhoe Driving Weight and Drop: C C Ground Surface Elevation: 1090 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ • This log is part of the report prepared by Convene for this project and F ,' , . 3 ~ ~` should be read together with the report. This summary applies only at the LL ~ H . . U location of the teat pit and at Lhe time of drilling. Subsurface conditions \ 7 Z + S t+ 2 may differ at other locations and may change at this location with the W N r ~ .. ~ a Q p passage of time. The data presented ie a simplification of actual conditions H J o H > U 2 ~ 0~ encountered. p m m E O a O OLD ALLUVIUM (goal) - SII.TY SAND (SM): fine grained sand, trace clay, pin-hole voids throughout, voids decrease with depth, rootlets upper 1 foot, dry, very dense, brown Refusal at 4 feet No groundwater encountered No caving Test pit backfilled 4/10/90 ` SCALE: 1'=5' trf=v) SKETCH a -- : N24°w Qo l, Project No. Drawing No. Converse Consultants Inland Empire 89-81-165-O1 ~-i$ Log of Test Pit I~lo. TP-10 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR Equipment: Backhoe Driving Weight and Drop: O Ground Surface Elevation: 1102 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ Thia log ie part of the report prepared by Converse for this project and ~ ,' , 3 +' should be read together with the report. Thia summary applies only at the O .~, U location of the teat pit and at the time of drilling. Subsurface conditions LL j = 2 M S may differ at other locations and may change at this location with the j 3 N ~ 4 W a ¢ C) passage of time. The data presented ie a simplification of actual conditions ~ y 7 J a a ~ O p J encountered. O _m at O E O +~ O OLD ALLUVIUM (goal) -SILTY SAND (SM), fine grained sand, trace clay, abundant open voids and rootlets to 3.5 feet, slightly moist, very dense, dark brown 5 - P SANDSTONE: fine grained, silty, weathered, massive, slightly moist, soft, brown End of test pit at 7.5 feet No groundwater encountered No caving Test pit backfilled 4/10/90 ' ' ° SC ALE: 1 = s crl=v) SKETCH a- - : N3 0 w Qoal -~ QP __ ~.. l 89 81e165-O1 ur~aw-ng no. Converse Consultants Inland Empire 19 Log of Tese PiY f\lo. TP-11 Date Drilled: 4/10/90 ~. ~quipment: Backhoe Ground Surface Elevation: 1120 feet C C Logged by: DCP Checked by: GFR Driving Weight and Drop: Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ This log ie part of the report prepared by Convene for this project and F ', , 3 +~ should be read together with the report. This summary applies only at the O ¢ ~ U location of the teat pit and at the time oT drilling. Subsurface conditions I L t + F M t may differ at other to<atione and may change at this Location with the j Y 3 N ~ 4 W a o ¢ O paeeage of time. The data preeenked ie a simplification of actual conditions ~ 7 J O ¢ ¢ r ~ ~~ encountered. O _m m E . O ~ O OLD ALLUVIUM (goal) -SILTY SAND (SM): fine grained sand, open voids and rootlets to 3 feet, dry, dense, dark brown -: BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, slightly weathered, 5 brown moderatel hard ft t i y , ve, so mass o End of test pit at 5.5 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1'=s' cN=v) SKETCH a -: N~5°w Qoal " . . _~ QP Converse Consultanes Inland Empire Project No. 89-81-165-01 Drawing No. A-20 Log of Test Pit fVo. TP-12 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR Equipment: Backhoe Driving Weight and Drop: O Ground Surface Elevation: 1096 feet Depth to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS saMa~es \ This log ie part of the report prepared by Converse for this project and ~ '. , 3 - +~ should be read together with the report. Thia summary applies only at the O O W f v U to<ation of the test pit and at khe time of drilling. Subsurface conditions LL \ ¢ 7 ra Z ^ F ,y R may differ at other locations and may change at Chia location with the W m ~ 7 .. ¢ tl passage of time. The data presented ie a eimpli[cation of actual conditions ~ j ; o ~ a F W O ~ o O J encountered. D m m E O~ O ALLUVIUM (Qal) -SAND (SP): fine grained sand, dry, loose, brown OLD ALLUVIUM (goal) -CLAYEY SAND (SC): fine to medium grained sand, very moist to 3 feet, moist to 8 feet, loose to medium dense, dark brown 5 ;: BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, clayey, slightly moist, 10 soft, brown End of test pit at 11.5 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1'=s• tH=v) SKETCH ~-: Nss°E Q~ i QO~~ QP'. Converse Consultants Inland Empire rroJeer rvo. 89-81-165-01 urawmg nu. A-21 Log of Test Pit No. TP-13 Date Drilled: 4/11/90 Logged by: DCP Checked by: GFR ~quipment: Backhoe Driving Weight and Drop: Ground Surface Elevation: 1075 feet Depth to Water: none encountered C C SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ _ Thie log is part of the report prepared by Converse for this project and ~ '. , 3 +~ should be read Yogether with the report. This summary applies only at the O O W F v U location of the teak pit and at the time of drilling. Subsurtate conditions ~ j Z Z M 2 may differ at other locations and may change at this location with.the j 3 N ~ 4 W a a¢ p passage of Lime. The data presented ie a simplification of actual condition s ~ Y j O ¢ d _ w ^ ~ O L7J encountered. ~ O m m O E O~ ! - O OLD ALLUVIUM (goal) -CLAYEY SAND (SC): fine grained sand, pin-hole voids to about 3 feet, slightly moist to moist, dense to very dense, dark brown 5 - : BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, slightly weathered, 10 massive, moist, soft, brown End of test pit at 11 feet No groundwater encountered No caving test pit backfilled 4/10/90 SCALE: 1'=s' It+=v> SKETCH a -: N2~°w Qoal p Converse Consultants Inland Empire Project No. 89-81-165-01 Drawing No. A-22 Log of Test Pit f\lo. TP-14 Date Drilled'. 4/10/90 Logged by: DCP Checked by: GFR Equipment: Backhoe Driving Weight and Drop: O Ground Surface Elevation: 1071 feet Dep[h to Water: none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ ~ Thie log ie part o[ the report prepared by Converee for Chia project and F ', , 3 +' should be read together with the report. Thie summary applies only at the o W ~ U location of the test pit and at the time of drilling. Subeur[ace conditions ~ ~ Z _ w = may differ at other locations and may change at this location with the j Y 3 N ^ 4 W tl passage of time. The data presented ie a eimplif cation o[ actual conditions ~ j O O ¢ ° ~ W O ~ ^ tl J encountered. ^ m J m E a ^ ~+ O OLD ALLUVIUM (goal) -SILTY SAND (SM): fine grained sand, open voids and rootlets throughout, dry, medium dense, brown 5 -- BEDROCK - PAUBA FORMATION (Qp) SANDSTONE: fine grained, silty, moderately weathered, massive; soft to moderately hard, brown End of test pit at 6 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1'=s' chi=v) SKETCH ~--: Nso°E Qoal . ~~P J ~~ Converse Consultants Inland Empire g9-81-165-01 A-Z3. Log of Test Pit iVo. TP-15 Date Drilled: 4/10/90 Logged by: DCP Checked by: GFR ~quipment: Backhoe Driving Weight and Drop: Ground Surface Elevation: 1078 feet Depth to Water: none encountered O SUMMARY OF SUBSURFACE CONDITIONS SAMPLES ~ This log ie part of the report prepared by Convene for this project and F, ', , 3 +~ should be read together with the report. This summary applies only at the U location of the teat pit and at the time of drilling. Subsurface tonditione LL j Z e M = may differ at other locations and may change at thin location wikh the j 3 N ~ w F a. a ¢ O passage of time. The data presented ie a simplification of actual tonditione ~ Y 7 O O w ¢ 4 F W p ~ O O J encountered. O m L9 E O ~+ O OLD ALLUVIUM (goal) -SILTY SAND (SM): fine grained sand, open voids throughout, slightly moist, medium dense, dark brown 5 CLAYEY SAND (SC): fine to medium grained sand, dark brown ]0 End of test pit at 13 feet No groundwater encountered No caving Test pit backfilled 4/10/90 SCALE: 1'=5' (H=V) SKETCH a -- : N40°W Qoal . ~. . -,.. _. Yro)etL NO. Lrawmg 1\O. Converse Consultants Inland Empire 89-81-165-01 ~-2~ Log of Test Pit ~o. TP-16 Date Drilled: 4/11/90 Logged by: DCP Checked by: GFR Equipment: Backhoe Driving Weight and Drop: O Ground Surface Elevation: 1075 feet Depth to Water. none encountered SUMMARY OF SUBSURFACE CONDITIONS SAMPLES \ _ This lag ie part of the report prepared by Converse for this project and F ,' , 3 +~ should be read kogether with khe repork. This eummary applies only at the U location of the teat pit and at the time oC drilling. Subsurface conditions LL \ ~ ~ Z x = i„i 2 may differ at other locations and may change at this location with the W vl F 7 ~ ¢ R ¢ p passage of time. The data presented is a simplification of actual conditions H J O H > U 2 O p J encountered. O m m E O a O 'OLD ALLUVIUM (goal) -CLAYEY SAND (SC): fine grained sand, rootlets and pin-hole voids to about 3 feet, dry, very dense, near refusal with backhoe, brown BEDROCK - PAUBA FORMATION (Qp) 5 SANDSTONE: fine grained, silty, dry, moderately hard, brown End of test pit at 6 feet No groundwater encountered No caving Test pit backfilled 4/]1/90 SCALE: 1'=s• cH=v) SKETCH ~-: Sso°E Qoal QP• Converse Consultants Inland Empire Project No. 89-81-165-01 Lrawmg NO. A-25 0 APPENDIX B LABORATORY TEST PROGRAM O O 89-81-165-01 Converse Consultants Inland Empire APPENDIX B LABORATORY TEST PROGRAM O Laboratory tests were conducted in a Converse laboratory on representative samples for the purpose of evaluating their physical properties and engineering characteristics. Test results are presented on the exploration logs (Appendix A) and in this appendix. A summary of the various laboratory tests conducted is presented below: In-Situ Moisture Content and Dry Density Data obtained from these tests, pertormed on relatively undisturbed ring samples obtained from the field, were 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 calculated dry density in units of pounds per cubic foot (pcf) are provided on the logs. Laboratory Maximum Density and Optimum Moisture Tests Two laboratory maximum density and optimum moisture tests were pertormed on representative bulk samples of the site materials. These tests were conducted in accordance with the ASTM D1557-78 laboratory procedure. Results of these tests are presented on Drawing B-1, "Compaction Test." O Shear Tests Direct shear tests were performed on both undisturbed ring and remolded samples. Individual rings were prepared, soaked and vertical surcharge applied. Each ring was then sheared at a constant rate of strain. A range of normal loads was applied and the shear strength envelope was determined. Results of the tests are presented on Drawings B-2 through B-4, "Direct Shear Tests." Consolidation Tests Data obtained from these tests, performed on relatively undisturbed and remolded soil samples, were used to evaluate the settlement characteristics of the site soils under load. Specimens were loaded into a test apparatus which contained porous stones to accommodate vertical drainage during testing. Normai vertical axial toads were applied to the ends of the sample through the porous stones, and the resulting vertical deflections were recorded at various time periods. The load was increased after the sample reached a reasonable state of equilibrium. Samples were loaded at field moisture and submerged for additional loading. Test results are shown on Drawings B-5 through B-9, "Consolidation Test." O 89-81-165-01 Converse Consultants Inland Empire B-2 Resistance R-Value Test O A selected bulk soil sample was tested to determine the 'R" value using the California "R" Value Test Method No. 301 (ASTM D 2844-69). Results of the 'R" value test are presented below: SANPL RESISTANCE BDRING SAMPLE DEPTH "R" No. No. (ft) SGIL DESCRIPTfoN VALUE° 8H-2 B-t 4-7 CLAY, Sandy 29 (Disturbed Pauba Fm Bedroek) BY exudation Soil Corrosivity Resistivity, pH, soluble sulfate, and chloride concentrations were determined for three soil samples to evaluate the corrosion potential of common construction material in contact with soil. These tests were performed by Converse Envirolab, and the test results are shown at the end of this Appendix. Sample Storaoe Soil samples presently stored in our laboratory will be discarded 30 days after the date O of this report unless this office receives a specific request to retain the samples for a longer period. O 89-81-165-01 Converse Consultants Inland Empire O 140 135 ~ 130 a z F x ~ 125 F z r a Q 1za _~ 115 110 0 i00 PERT SPECIFIC 5 10 15 20 MOISTURE CONTENT IN PERCENT 'ENT SATURATION GRAVITY = 2.70 SAMPLE DEPTH TEST OPTIMUM MAXIMUM DRY SYMBOL LOCATION (ft) DESCRIPTION METHOD MOISTURE (ss) DENSITY (pcf) O BH-1 8-10 SANDSTONE ASTM D-1557 9.8 128.0 ^ BH-5 O-2 SILTY SAND(Sld) PSTM D-1557 6.0 115.9 COMPACTION TEST O CAMPOS VEDES RESIDENTIAL DEVEL. Project No. For: Mesa Homes 89-B1-165-01 C®eave~s~ CoaosuB~a~a$s U~aBaau~ Eavoj~6Pe Figure No. B-1 2.0 O ~, to x z W l.o a F fn a d w x .o 2.0 w x z rn to ~ 1.0 F U] d' W x in c .0 1.0 2.0 3.0 NORMAL STRESS IN KSF 4.0 5.0 .0 .1 .2 .3 .4 .5 HORIZONTAL DEFORMATION IN INCH BORING/SAMPLE BH-1/Bulk DEPTH (ft) 8-10 DESCRIPTION Remold:SAND(SP) with silt =~~Cdisturbed Pauba sandstone) STRENGTH INTERCEPT (ksf) .160 (PEAK STRENGTH) FRICTION ANGLE (degree) 38.8 (PEAK' STRENGTH) ',=Remolded to 90 -% of the AS TM 0 1557-78 Laboratory maximum density near optimum moisture. MOISTURE DRY DENSITY VOID NORMAL PEAK RESIDUAL SYMBOL CONTENT (sa) (pcf) RATIO STRESS (kst) SHEAR (ksf) SHEAR (ksf) O 8.B 115.6 .446 .50 .66 .45 ^ 9.3 115.0 .455 1.00 .81 .79 0 9.1 115.1 .453 2.00 1.82 1.49 DIRECT SHEAR TEST CAMPOS VERDES RESIDENTIAL DEVEL. Project No. O For: Mesa Homes 89-81-165-01 Co~eeas~ Coeasu9$aa~4s VaaBseaa9 ~avu~6Q~, Figure No. B-2 O 4.0 w Tn x z w 2.0 x F (z 6 W x ~ .~ 2 O w x z w 1. a F a .0 .1 .2 .3 .4 .5 HORIZONTAL DEFORMATION IN INCH BDRING/SAMPLE BH-1/S-4 DEPTH (Pt) 24-25 DESCRIPTION :SANDSTONE STRENGTH INTERCEPT (ksf) .442 (PEAK STRENGTH) FRICTION ANGLE (degree) 42.6 (PEAK STRENGTH) MOISTURE DRY DENSTTY VOID NORMAL PEAK RESIDUAL SYMBOL CONTENT (sa) (pcf) RATIO STRESS (ksf) SHEAR (ksf) SHEAR (ksf) O 10.8 92.6 .805 .50 .87 .62 ^ 14.3 89.7 .864 1.00 1.41 1.15 0 2.9 97.9 .709 2.00 2.27 1.84 DIRECT SHEAR TEST O CAMPOS VERDES RESIDENTIAL DEVEL. Project No. For: Mesa Homes 89-81-165-01 Figure No. H-3 C®auv~ase Coaasu8$alo~$s ~~Val~o~ ~~uu~BP~ .0 2.0 4.0 6.0 8.0 10.0 NORMAL STRESS IN KSF ~, x z v~ w a m a w x w x z ., w a F U1 Q'. C' W x 4.( 2.0 .o z.1 v .0 .1 .2 .3 .4 .5 HORIZONTAL DEFORMATION IN INCH BORING/SAMPLE BH-3/S-6 DEPTH (ft) 39-40 DESCRIPTION :CLAYEY SILTSTONE STRENGTH INTERCEPT (ksf) 1.3fi6 (PEAK STRENGTH) FRICTION ANGLE (degree) 30.0 (PEAK STRENGTH) MOISTURE DRY DENSITY VOID NORMAL .PEAK RESIDUAL ~ SYMBOL CONTENT (sa) (pcf) RATIO STRESS (kst) SHEAR (ksf) SHEAR (ksf) O 12.7 118.5 .411 .50 1.69 1.08 ^ 12.2 118.2 .415 1.00 1.90 1.47 0 13.2 115.6 .447 2.00 2.53 2.02 DIRECT SHEAR TEST CAMPOS VERDES RESIDENTIAL DEVEL. Project No. For: Mesa Homes 89-81- 165-01 Figure No. H-4 C®nd~PSe Coa~suV$s~o$s Ve~6saaa9 Emru~iP~ - ..o O SO LOAD IN HIPS PER SQUARE FOOT v 2 F x w x z '" 4 W zs z d x U F z s W U a w a -----4---~- 8 BORING BH-5/S-2 DEPTH (ft) 9-10 SPEC. GRAVITY DESCRIPTION SAND(SP) MOISTURE DRY DENSITY PERCENT VOID CONTENT (~) (pcf) SATURATION RATIO INITIAL 12.9 120.7, 89 .394 FINAL 13.1 124.3 100 .353 Note: Solid circles indicate readings after addition of water ~2 .394 .366 .338 F C4 Q O .310 7 .262 .255 CONSOLIDATION TEST O CAMPOS VERDES RESIDENTIAL DEVEL. Project No. For: Mesa Homes 89-81-165-01 Figure No. B-5 C®E6H~PS~ CoavsuV$aaa4s ~euVsa~~ Ee~oQaaPe LOAD IN HIPS PER SQUARE FOOT 10' 1 10 lOZ a SSs 2 .561 F x ., w x z 4 .szs W o ~ z H a a x U q F ,7, 6 ~ .497 7 W U tz W a. g .465 10 .433 BORING BH-5/S-3 DESCRD?TION SILT(ML) DEPTH (ft) 19-20 SPEC. GRAVITY 0 MOISTURE DRY DENSiTP PERCENT VOID CONTENT (sa) (pcf) SATURATION RATIO INITIAL 13.7 116.3 69 .593 FINAL 18.4 119.6 100 .548 Note: Solid circles indicate readings after addition of water CONSOLIDATION TEST OAMPOS VERDES RESIDENTIAL DEVEL. Project No. For: Mesa Homes 89-81-185-01 ConN~PS~ ~OPISUO$S69$S ~POISPdf~ ~Pd9~IP~. Figure No. H-6 O O LOAD IN HIPS PER SQUARE FOOT 10' 1 10 1( 0 2 E x w x z '" 4 z a x U F W 6 U a w a. 8. to z .491 .462 432 O F a Q O .402 ~ .372 .342 BDR[NG BH-6/S-2 DESCRIPTION SILTY SAND(SM) DEPTH (ft) 9-10 SPEC. GRAVITY MOISTURE DRY DENSITY PERCENT VOID CONTENT (~) (pcf) SATURATION RATIO INITIAL 10.2 115.8 58 .491 FINAL 15.3 121.2 100 .426 Note: Solid circles indicate readings after addition of water CONSOLIDATION TEST O CAMPOS VERDES RESIDENTIAL DEVEL. Project No. For: Mesa Homes 89-81-165-01 COB9M~PS~ COfiSUS~aPB~S AP9~~P9~ ~8Y9~iP~ Figure No. H-7 LOAD IN HIPS PER SQUARE FOOT 10 ~ 1 10 lOZ o .sso z sts F x c~ w x z "" 4 .488 ~ O z ~ ~ x U C] E-' O W 6 .457 ~ U a w a 8 .426 10 .3B5 BORING BH-9 S-1 DESCRIPTION SILTY SAND(SM) DEPTH (ft) 4-5 SPEC. GRAVITY MOISTURE DRY DENSITY PERCENT VOID CONTENT (ss) (pcf) SATURATION RATIO INITIAL b.7 112.2 34 .550 FINAL 15.1 122.2 100 .423 Note: Solid circles indicate readings after addition of water CONSOLIDATION TEST CAMPOS VERDES RESIDENTIAL DEVEL. For: Mesa Homes Project No. 89-91-165-01 O Figure No. B-8 Q~®PBH~PS~ Q:OEBSIdB$SPfl$S VB9VSB9~ EP~~OP~ ~o O LOAD IN HIPS PER SQUARE FOOT 010 I 1 10 10 z F x w x z '" 4 W L3 z x c.1 F z s w U W - 0.. _ 8 10 z ssz .sso szs O F a a Q 0 .497 7 .465 .433 HOR[NG 13H-9 S-2 DESCRIPTION SILTY SAND(SM) DEPTH (ft) 9-10 SPEC. GRAVITY MOISTURE DRY DENSITY PERCENT VOID CONTENT (~) (pcf) SATURATION RATIO INITIAL 7.3 111.2 35 .592 FINAL 17.4 118.4 100 .495 Note: Solid circles -indicate readings after addition of water CONSOLIDATION TEST O CAMPOS VERDES RESIDENTIAL DEVEL. Project No. For: Mesa Homes 89-91-165-01 Figure No. B-9 Coa~dePSe CoaasuBfaaa~s VuaVsend ~atm~aeP~ CONVERSE ENVIROLAB 67 West Bellevue Orive Suite O Pasadena, Califnmia 911 OS-250'i Telephone: B1 B/79~8200 O ~~Vr-1 May 1, 1990 PROJECT/CLIENT MESA HOMES San Bernardino PROJECT NO. :89-61-165-01 PROJECT ENG./MGR. Quazi Hashmi Subject Analysis of Samples ENVIROLAB N0. :90-71-04-137 On April 13, 1990 one (1) soil sample was delivered to the laboratory O to be analyzed by ASTM methods for pH, chloride, soluble sulfates; and minimum resistivity. The sample was analyzed on April 26, 1990. The results which were obtained are listed in the attached table. ~~'`- ~ ., George Colovos, Ph.D Laboratory Director O 4CONVE RSE PROFE SSION4L GROUP CGMPnNv 0 PROJECT/CLIENT MESA HOMES REPORT DATE May. 1,1990 PROJECT N0. 89-81-165-01 DATE ANALYZED Apr. 26,1990 PROJECT ENG./MGR. Quazi Hashmi DATE RECEIVED Apr. 13,1990 ENVIROLAB N0. 90-71-04-137 RESULTS ANALYSIS OF SOIL SAMPLE TABLE 1 BH#6,BAG#1 ANALYTE @7'-8' UNITS pH 7.52 N/A Soluble Sulfates 41 mg/kg Soluble Chlorides 3.5 mg/kg Minimum Resistivity 4500 ohm.cm O -NA Not Applicable Reviewed by: ~C~~t - ~ZL~ ~ Shu-Teh Pan Organics Lab Manager O Approved by~.._. George Colovos,Ph.D Laboratory Director CONVE FISE ENVIROLAB ~. ~!~ ~ M Q ~ U W/~~/ Q YV ~ ~ 0 ~ ~ ~ ~ ~ N ~ m U a E LL = Q ~ 0 J ~_ a m O Z C U W ~pp d ~ ®om I si ~ e 6 O U o m m gal c m [[GG~~ m o"aX I`~ m< mLL p~~ a d L`~ m N Qfl ! m !!d 0 m m n > f0 m m m m m C m o m t 3 m m ~mr i m E ~ ^1 ' r m Y N E `~ ~ m ¢ m o \ a m 0 m m m T m c Q S ~ `7 C ' ~ =~. ~ J ~ ~ ~ 6 E ~ x /~ I ~C~ ,~~ h, U ~I ~~ S U 1 C ~i ~`~ r ~ ~\ n m C U - ^ \ J ~ !. ~ S ~o V ~ V ,, v i V~ ~ m ~ S ~~ _ ~ a E\ v a ~ 1 a 2~ ? l ~ ~o ~ m ~ - ~ `; ~ ~ s ~ m E L n ° m .:. ` U z' m E G v m r ~ m U N 1 p a ~' m n ~: r y 1 ~ ~ \ a~ . m ~ ` ~ .Q 1 ~ ~' x _ y n~ m v 1 ~ h °~ l ~ ~ ~ a m d I V~ E n r m m O' m E _~ m m a m c a m m n T a a T T a a T T c a T m Z ~ m J m ~ m E ~ m m ~ a a m m a a m n m ~ ~ ~ ~ ~ m 0 m 0 m o a m a .-- _ c ~ c ~ c ~ ~, a a a` m~ E J m ~ ~ m ¢ m ¢ m ¢ m ¢ m ¢ m ¢ 0 PROJECT/CLIENT MESA HOMES REPORT DATE May. 1,1990 PROJECT N0. 89-81-165-01 DATE ANALYZED Apr. 26,1990 PROJECT ENG./MGR., Quazi Hashmi DATE RECEIVED Apr. 13,1990 ENVIROLAB N0. 90-71-04-137 RESULTS ANALYSIS OF SOIL SAMPLE TABLE 1 BH#6,BAG#1 ANALYTE @7'-S' UNITS pH 7.52 N/A Soluble Sulfates 41 mg/kg Soluble Chlorides 3.5 mg/kg Minimum Resistivity 4500 ohm.cm o NA Not Applicable R4ev/iewed by: Shu-Teh Pan (~_ Organics Lab Manager O Approved by~.... °~"' ~ George Colovos,Ph.D Laboratory Director CONVE47SE EN VIR OLAB O APPENDIX C STABILITY ANALYSES O O 89-81-165-01 Converse Consultants Inland Empire APPENDIX C STABILITY ANALYSES O Stability analyses for deep-seated failure were performed for the proposed cut and fill slopes. Surficial stability was also checked. Geologic cross-sections used in the analyses are presented on Drawings 2 through 4. Stability evaluation were performed using Janbu's Method (stability. charts). Soil strength parameters used to determine surficial stability and deep-seated stability are presented below: SOIL STRENGTH COHESION FRICTION UNIT WEIGHT t. osf de ree 7. ocf 1 sut c ~ Su rf icial 300 35 130 e Deep-Seated 300 35 120 2. Fill Slopes • Surf icial 160 35 ~ , 130 e Deep-Seated 160 35 120 O Results of our analyses indicate that the slopes have adequate factor of safety against failure. O 89-81-165-01 Converse Consultants Inland Empire C-2 2:1 (HORIZOPITAL:VERTICAL) FILL SLOPE (40 FEET HIGH) O SURFICIAL STABILITY Assumption: yt = soaked unit weight = 1301b/ft~ 7b = buoyed unit weight = ryt - 62.a ~3 = depth of submergence = 3 feet ~ = slope angle =2656 ° ~ = 3S c = 160 psf Stability Analysis yb•~ cosh tangy + c F.S. _ -2r 7t sin ~ cosy = 67.6 • 3 • cosz26.56 • tan35° + 160 O 3 • 130 • Sin26.56 • COS26.56 __ 274 156 FS = t.76 O 89-81-165-01 Converse Consultants Inland Empire C-3 O 300 20C z 100 v E SC 2 T 2( N I( 0 V V ' I()(] 50 30 20 IS 10 B 6 4 2 I O g 0 ' I 2 3 4 5~ Slone Rollo 0=cot /3 . For c°0 _J F= ~ 61on d ' I i i i r _- r-- ' ~ ~ i i I 1 I __ { I. ~_~ ~~ l i i i ,_~_ J .~1~ ' .. i I- I I ~ - F `Ncf pd ~ L - I I ~. --r Pr lan~ _ f ~ _ O Slope stability charts for ~ > 0 soils (after Janbu, 1960) o Stability Analysis ac ~ = Petan¢ _ t2o• ao • tanss° = 21.00 C t6o From the above chart, for a = 2t.00 and slope ratio of 2, the Critical Stability Number Ncf = ~ Factor of Safety, F = Ncf C = 60 • 160 = 2.0 Pd ao • tzo O DEEP-SEATED ANALYSIS 89-81-165-01 Converse Consultants Inland Empire C-4 2:1 (HORIZOIdTAL:VERTICAL) CUT SLOPE (40 FEET HIGH) SURFICIAL STABILITY Assumption: ryt = soaked unit weight = 1301b/ft3 ryb = buoyed unit weight = ryt - 62.4 ~ = depth of submergence = 3 feet ~ = slope angle = 26.SG ¢ = 3~ c = 300 psf Stability Analysis ryb•$ cosh F.S. _ tan ~ + c 3 ryt sin ~ cosh = 67.6 • 3 • cosz26.56 • tan35° +300 3 • 130 • sin?b.56 • cos2b.56 __ 413.6 155.98 FS = z.65 O O O 89-81-165-01 Converse Consultants Inland Empire C-5 O O DEEP-SEATED ANALYSIS 300 ZOC z IOC E 5C 2 a. D 2( l( u V irv, 0 O 0 5 0 3 i O s 0 N W 7 0 ' I 2 3 4 5 Slope Rotio b=cot (3 For c•0 i F= ~ b tan ~ ~ I i I i ~ i i ~ - __I r , _ _ _ r ~. i ..~ _ u i i ~ i i ~_~+_ =_ ~ i.. --•- I - J..~ _ i T r_~-- __ J- ~ T .. I .~_.~ __ i r~ ~. _ ~ C I' I I F `Ncf ~d , ' ` - ~ i _ I II ~ ~ I ~ , - P~lon~ ~'~d c - i ~ I Slope stability charts for ~ >0 soils (after Janbu, 1960) AssumQtion o Cohesion, C = 300 psf o Friction ¢ = 3S Unit weight, ry = 120 pcf Stability Analysis: o ac ~ = Petan~ = 120• 75 • tan35° = 11.2 C 300 From the above chart, for a~ = 11.2 and slope ratio = 2, the Critical Stability Number Ncf = 37 0 Factor of Safety, F = Ncf C = Pd =37X145 120 X 40 FS = 2.30 89-81-165-01 Converse Consultants Inland Empire 0 APPENDIX D RECOMMENDED EARTHWORK SPECIFICATIONS O 89-81-165-01 Converse Consultants Inland Empire APPENDIX D RECOMMENDED EARTHWORK SPECIFICATIONS O Gr din 1. Existing septic tanks and other underground storage tanks must be removed from the site prior to commencement of building, grading or fill operations. Underground tanks, including connecting drain fields and other lines, must be totally removed and the resulting depressions properly reconstructed and filled. Removal of underground tanks must be performed in accordance with the requirements of applicable regulatory agencies. Depressions left from tree removal shall also be properly filled and compacted. 2. Abandoned water wells on the site shall be capped according to the requirements of the appropriate regulatory agencies. The strength of the cap shall be at least equal to the adjacent soils. The final elevation of the top of the well casing must be a minimum of 36 inches below adjacent grade prior to grading or fill operations. Structure foundations should not be placed over the capped well. The locations of any abandoned wells should be accurately surveyed and shown on the as-built grading plans. O 3. The methods for removal of subsurface irrigation and utility lines will depend on the depth and location of the line. One of the following methods may be used: a. Remove the pipe and compact the soil in the trench according to the applicable portions of these grading recommendations. b. The pipe shall be crushed in the trench. The trench shall then be filled and compacted according to the applicable portions of these grading specifications. c. Cap the ends of the line with concrete to mitigate entrance of water. The length of the cap shall not be less than 5 feet. The concrete mix shall have a minimum shrinkage. 4. Subdrains shall be installed as discussed in Section 6.4. Clean-outs shall be observed by an Engineering Geologist or Soils Engineer prior to installation of Subdrains. O 89-81-165-01 Converse Consultants Inland Empire D-2 5. Areas to receive compacted fill shall be stripped of all vegetation, organics, and O debris. Any existing non-structured fill materials and other unsuitable soils shall be excavated as recommended by Converse Consultants Inland Empire (CCIE). All areas that are to receive compacted fill shall be observed by CCIE prior to placement of fill. 6. 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 or slightly above 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 inplace soil density to the laboratory maximum dry density as determined by the ASTM D1557-78 test procedure. 7. 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. Each layer shall be compacted to at least a minimum relative compaction'of 90%, except fill placed 40 feet or more below final grade shall be compacted to 95% relative compaction. Pavement base material shall be compacted to at least 95% of the ASTM O D1557-78 laboratory maximum density. 8. Fill soils shall consist ofexcavated onsitenon-expansive'soils essentially cleaned of organic and deleterious material or imported soils approved by CCIE. All imported fill shall be granular and non-expansive with an Expansion index (EI) less than 20, as defined by the Uniform Building Code (UBC) Standard 29-2. Rocks larger than 6 inches in diameter shall not be used as fill unless they are sufficiently broken down. 9. When till material includes rock, large rocks will not be allowed to nest and voids must be carefully filled with small stones or earth and properly compacted, as discussed in Section 6.11. 10. CCIE shall. evaluate and/or test import materials for conformance with specifications prior to delivery to the site. The material used shall be free from organic matter and other deleterious material. The contractor shall notify CCIE at least two working days prior to importing fill to the site. O 89-81-165-01 Converse Consultants Inland Empire D-3 O 11. CCIE shall observe the placement of compacted fill and conduct inplace field density tests on the compacted fill to check for adequate moisture content and relative compaction as required by the project specification. 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 for the soils engineer to conduct field density tests on. The contractor shall provide safe and timely access for CCIE personnel throughout the grading site to allow continued monitoring and testing. 12. Earth-moving and working operations shall be controlled to prevent water from running into excavated areas. Excess water shall be promptly removed and the site kept dry. 13. Wherever, in the opinion of the Owner's or CCIE's Representatives, an unstable condition is being created, either by cutting or filling, the work shall not proceed in that area until an investigation has been made and the grading plan revised if found necessary. O 14. Fill material 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 CCIE indicate that the moisture content and density of the fill are as previously specified. 15. Whenever the words "supervision°, "inspection", or "control" appear they shall mean observation of the work and testing of the fill placement necessary by CCIE for substantial compliance with plans, specifications and design concepts. Erosion Control 1. 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. 2. 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 offsite. O 89-81-165-01 Converse Consultants Inland Empire D-4 3. A suitable proportion of slope plantings shall have root systems which will O 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. 4. Construction delays, climate/weather conditions, and plant growth rates may be such that additional short-term, non-plant erosion control measures may be needed including matting, netting, sprayed compounds, deep (5 feet) staking, etc. These measures shall be reviewed by CCIE. 5. Rodent burrowing, small concentration of uncontrolled surface/subsurface water, or poor compaction of utility trench backfill on slopes shall be repaired and controlled as soon as possible. 6. All possible precautions shall be taken to maintain moderate, uniform soil moisture. Slope irrigation systems shall be properly operated and maintained. 7. If completion of new slopes occurs during the rainy season, contingency plans shall be developed to provide prompt temporary protection against major O erosion/sloughing. Offsite improvement shall be protected from site runoff. 8. Any erosion damage which occurs prior to the completion of the project shall be repaired by the Contractor. O 89-81-165-01 Converse Consultants Inland Empire ~\ • ." •' PROPOSED COMPACTED FILL :. •' ' ~ _ ~ - i NOTES: .~.. ~a • • NATURAL GRADE •,.~, ~' ~ '. '~•~ ~ ~ UNSUITABLE MATERIAL • . ~ •: .. .1~. • •~~... . • \ `• •• J TYPICAL BENCHING SEE DETAIL BELOW 0 • ~ - MINIMUM CLEARANCE . - _~~ ,' , , .DIMENSIONS •' Pipe shall be a minimum of 4 inches diameter and runs oT 500 feet or more shall use 8-inch diameter pipe, or as recommended by the soil engineer ~ - 0 r 0 0 i O ° a °oo° ° O (~ O Z O ~ Q e ~ > ~ p° c a Q 6 p Depth and Bedding ° U ~ ~ May Vary with ° p ° ° Pipe and Load ~ ° 0 e Characteristics. 6' MIN. 6' MIN. 3' Feet Typical p a ° O O o 0 ° Z a o o o ° D o Q ~ ~ Q po~ ° ° o o p 18' MIN. Feet TYPIC COMPETENT MATERIAL ' • ..ice. FILTER MATERIAL -Minimum of nine cubic feet per foot of pipe.See Figure tb for filter material gradation ALTERNATE: In lieu of filter material nine cubic feet of gravel per foot of pipe may be .encased in filter fabric. See Figure 1 b for gravel specifications.Filtei fabric shall be Mirafi 140 or equivalent. Filter fabric shall be lapped a minimum of 12 inches'on all joints. Minimum 4-inch-diameter, PVC SCIi 40 or ABS Class SDR-35 with a crushing strength of et least 1000 pounds, with a minimum of Buniformly-spaced pertoratlona per foot of pipe, installed with perforations on bottom of PIPe• TYPICAL CAllIYO1~1 SUBDRAIRI DETAIL CAMPOS VERDES RESIDENTIAL DEVELOPMENT Project NO. Temecula, California- 139-81-165-01 for: Mesa Homes Figure No. ~:®~F9~PS~ ~®QO$tEV$~B9$S VPOVSIP9@~ ~ITSh1~UQ~ D-1a i• • - ~ •/ . i . ~~ •~~ .'~yi ~',' •'.• ~ NOTE: --~ Downstream 20' of pipe at outlet shall be norperforated and backfilled with fine-grained material FRTER MATERIAL: Filter material shall be Class 2 permeable material (Caltrans Standard Specification 68-1.025) or approved alternate. Class 2 grading as follows: PERFORATED 6° MIN. SUBDRAIN ALTERNATE A: Perforated Pipe Surrounded with Filter Material 40 FILTER FABRIC o 0o at OVED EQUIVALENT ~ co ~0 0 ~ ~ \\ 1-1/2° MIN. GRAVEL OR APPROVED EQUIVALENT NOTE: In addition to the wrapped gravel, outlet portion of the subdrain should ' t>a equipped with a minimum of 10 feet long perforated pipe connected to a nonperforated pipe having a minimum of 5 feet in length inside the wrapped gravel. SUBDRAIN ALTERNATE B: 1-1/2° Gravel Wrapped in Filter Fabric I • SIEVE SIZE PERCENT PASSING FILTER MATERIAL ' ~ '. • ' MIN. 9-CU. FT. . ~ ~ ie' MIN.. • . 100 1 o- PER LINEAL FT. ~ ~ --loo 3ie' ad \ ~ 1 B' ~y, 18' O No.4 25-40 No. S ~ 18-33 ~ MIN. ~ MIN. ~ ~ No.30 5-15 - ' ~ No. 60 0-7 ~ 8' MIN.'. ~. ~ D-3 No. 200 6° MIN. OVERLAP ~~ MIRAFI 1 OR APPR SUBDRAIN INSTALLATION - Subdrain pipe shall be installed with perforations down or, at locations designated by the geotechnical consultant. SUBDRAW TYPE - Sutxlrain type shall he ASTM C508 Asbestos Cement Pipe (ACP) or ASTM D2751, SDR 23.5, or ASTM D1527, Schedule 40 Acrylonitrfle Butadiene Styrene (AUS) or ASTM D3034, SDR 23.5, or ASTM D1785, Schedule 40 Potyvirryl Chloride Plastic (PVC) pipe or the approved equivalent. 0 0 z 'TYPICAL CANYON SUBDRAIIli DETAIL (continued) CAMPOS VERDES RESIDENTIAL DEVELOPMENT Proiec~NO. (/~ Temecula, California 89-81-165~s._. for: Mesa Homes ~~j~~ Figure No. t~~i ~®POH~P~S~ ~®PDSBEV$~Q9$S VP9V~PO~I ~P~t1~OP~ D-1tr of O a 0 0 a b a d 0 O 1:1 i ~ UNWEATHERED BEDROCK ncr~nv~ min COMPACTED FILL NATURAL GROUND _ V~- i i i 5. °+ 3' UNWEATHERED BEDROCK C~J'r-~@~L ~~~ (~PSPISIfIOPI~ NATURAL GROUND 1 i ~i i i ~ i ~ i i ~ ~ ~ ~/~ // 5' i / '~ / 3' COMPACTED FILL i i ~ / i ~ ~ ~ / ~ OVEREXCAVATE and ~ ~yV\uM' REPLACE with ~ ~ GO\'~ ~yOE' j / COMPACTED FILL UNWEATHERED ~OPSO\\" ~08EC / BEDROCK ~~p'~\~ER/ UNWEATHERED BEDROCK T'~f~IC~eL. 'TFtAIlTSI'd'IORI II.®'T ®E'TAII. _ _ CAMPOS VERDES RESIDENTIAL DEVELOPMENT Prolec~NO. Temecula, California 89-81-165-01 for. Mesa Homes ._ Plgure No. C®Ptl!l~PS~ Q°sOQDS6d8$SP9{~S VP11V31POQI ~P9flQ90P~ D-2 . .~ ' ..COMPACTED FILL ~ ' NONPERFORATED~ ~ ~ •', •• OUTLET PIPE • • • ' ~ ~ •t~ ~ • .~ l ~~ T a PROJECTED PLANE 1 to 1 maximum from toe of slope to approved ground NATURAL GROUND '~i. ~ _~,. . y. y.~ ~: . . .. •~ -. , : 4' Typical REMOVE 1. :.,~ ~ . . .'. ~. :/•: .~ •• %. . 9 -~ 2' MIN. KEY DEPTH 16' MIN. LOWEST BENCH (Key) BENCH UNSUITABLE HEIGHT MATERIAL BACKDRAIN for SLOPES OVER 15 FEET In HEIGHT VUOTES: A n 0 a m o' LOWEST BENCH: Depth and width subject to field change based on consultant's inspection. SUBDRAINAGE: Back drains may be required at the discretion of the geotechnical consultant. FILE OVEl2-1~1A'TUFtAL SLOPE CAMPOS VERDES RESIDENTIAL DEVELOPMENT Proieci NO. Temecula, California 89-81-16~ fdr: Mesa Homes• ~1 FVqu~e No. C®~oe~PS~ C®au~tuV$~~o4s O~oU~~o~ f~P1ro~6Pe D-3 O PROPOSED SURCHARGE FILL-OVER-CUT SLOPE FORMER NATURAL PROFILE i i /// •.',PERMEABLE COMPACTED_FILL •. - . .. •, •~~ ~•~ `•.. >1 'BENCHED IF>5:1 SLOPE TYPICAL SUBDRAIN at HEEL of KEY(See Subdrain Detail below) EQUIPMENT-WIDTH KEY at 2-FOOT MINIMUM DEPTH and 296 FALL to HEEL 0 a' S n a 0 a v i; a O LOW PERMEABILITY BEDROCK FILTER MATEAIAL 3 ft3/ft. T-CONNECTION 5% MIN.ti OUTLET PIPE ~8" MIN. ~4" MIN. PERFORATED PIPE 4"{d MIN. ~ACaDRAIW DETAIL 9 FILTER MATERIAL Filter material shall be Class 2 permeable material per State of California Standard Specifications. or approved alternate. Class 2 grad'mg as follows APPROVED GEOTEXTILE NON PERFORATED OR EQUIVALENT OUTLET PIPE .; _ 4~ ;n i \~~ 1-1/2" PERFORATED OPEN GRAVEL COLLECTOR PIPE - AL'P. BACaDRA1W DETAIL 2 SIEVE SIZE PERCENT PASSING 1" 100 1/4" 90-100 3/8" 40-100 No. 4 25-40 No. 8 16-33 No. 30 5-15 No. 50 0-7 No. 200 0-3 D~~g~~G~ ~~.~~vx~T ®~T~g~. CAMPOS VERDES RESIDENTIAL DEVELOPMENT Proiecl NO. Temecula, California- - 89-81-165-01 fnr Mesa-Homes. C®~eePS~ C~e~suV~~eu$s Or~V~aodl EefIO~6P~ Figure No. D-4 CUTlFILL CONTACT SHOWN on GRADING PLAN COMPETENT MA a' c 0 V a 0 n 0 0 m 'o CUT/FILL CONTACT to be SHOWN on'AS-BUILT' NATURAL GRADE .~ CUT SLOPE - CUT SLOPE to be CONSTRUCTED PRIOR to PLACEMENT of FILL KEYWAY In COMPETENT MATERIAL MINIMUM WIDTH of 15 FEET or ea RECOMMENDED by the SOIL ENGINEER B' MI ~~. . COMPACTED FILL - -'.'--~'-~ 'MpT~-Rt AL "- " • • ' . SABLE. __ +/ARIABLE~- F~M~VE'' • ,-/ I' ~ 4' MIN. (~ MINIMUM HEIGHT of BENCHES le 4 FEET-or ea RECOMMENDED by BEDROCK or APPROVED COMPETENT MATERIAL the SOILS ENGINEER BACKDRAIN o} SLOPE le HIGHER THAN 25 FEET and BEDROCK la IMPERVIOUS MINIMUM 1' TILT TRACK or 2% SLOPE (whichever Ia greater) NONPERFORATED OUTLET PIPE TYPICAL FILL ABOVE CUT SLOPE CAMPOS VERDES RESIDENTIAL DEVELOPMENT P~oiectNO. f/~' Temecula, California $9-81-165/ for: Mesa Homes ~®B~H~PS~ ~®P9S6AB~~1P9~S Iaul~au~l E9~ilQ8IP~ Figure No. D-5 NOTES: ~ FILL BLANKET Fill blanket, back cut, key width and key depth ere aub)ect to field change, 30' MIN. per report/plane ~ ~•--15° MIN O a 0 V a a 0 a m 0 O Key heel aubdrain, blanket drain, or vertical drain may De required et the discretion of the geotechnicel consultant. BACKDRAIN INSTALLATION - Beckdrain pipe shell be installed with perforations down.~Backdraln outlets shall be nonpertorated pipe. The perforated collector should extend the length of the backdraln. BACKDRAIN PIPE - Backdreln pipe shall be ASTM C508 Asbestos Cement Pipe (ACP) or ASTM 02751, SDR 23.5 or ASTM D1527, Schedule 40 Acrylonitrlle Butadiene Styrene (ABS) or ASTM D3034 SDR 23.5 or ASTM D1785, Schedule 40 Polyvinyl Chloride Plastic (PVC) •.::'/. j. .. ,/ .. j /. BACK CUT ./ / 1:1 or FLATTER • ~ - '/•~~ BENCHING . -/. BACKDRAIN /. '. (See Detail Below) pipe or approved equivalent. . ~ ~ OUTLET PIPES - , KEY DEPTH 1"-' Nonperf orated Pipe, i00' mez. O.C. Horizontally,./' ' 30' mez. O.C. Vertically ./: ~:' . ~ `-~/~ 10' MIN. EA. SIDE PERFORATED PIPE -' '/; f'~ KEY WIDTH 2' MIN. Equipment size -generally 15 feet FILTER MATERIAL- 3 tt.'/tt. T-CONNECTION 555 MIN. OUTLET PIPE 8' MIN. 4' MIN. .PERFORATED PIPE 4'Ib MIN. BACKDRAIW DETAIL. 9 ALT BACKDRAIid DETAIL 2 FILTER MATERIAL SIEVE SIZE PERCENT PASSING Filter material shall be Class 2 1°. 100 permeable material per State of 1/4' 90-100 Califorhia Standard Specifications.. 3/B° 40=100 or approved alternate. No._4 25-40 Class 2 grad'mg as follows No. 8 18-33 No. 30 5-15 No. 50 0-7 No. 200 0-3 ~LJ'fTIZESS or S'I'P~I3II..IZP,'I'I®IV FILL ®E'TP~IL :.AMPOS VERDES RESIDENTIAL DEVELOPMENT Fmieci NO. Temecula, California 89-81-165-01 for: Mesa Homes i~ Ficure No. ~o~ob~rrse C®euseaB~aea~s I>~IB~o~I Ea~v~BP~ NONPERFORATED OUTLET PIPE CAP FOR ALT.. B T-CONNECTION APPROVED GEOTEXTILE NON PERFORATED OR EQUIVALENT OUTLET PIPE - -- ~_- - ~ - ~- ~ -~ 1-1/2' PERFORATED OPEN GRAVEL COLLECTOR PIPE D-6 FINISH GRADE S a _a D N J SLOPE FACE • 10' MIN.. • •. •• COMPACTED FILL ~;~ , ~ _ ' 4' MIN. .. . ' - '~ • ' ~ I'°- 16' MIN. -~-I - GRANULAR SOIL - . • - To fill voids, _ densified by flooding • ' - •`~ ~'=:- ~. - ®~~~0~ ItOCI{ ®ISPOSAI. ®E'I'AII. FOIE ISOI.A'I'E® I3~JI3Ie~I. CAMPOS VERDES RESIDENTIAL DEVELOPMENT Pro~ecr NO. Temecula, California 89-81-165 for: Mesa Homes ~, Figure No. ~®P9N~PS~ ~®OUS6E0$~911$S OPDV81P0~ ~P90~9P~ D-7 0 APPENDIX E STATISTICAL SEISMIC RISK EVALUATION o O 89-81-165-01 Converse Consultants Inland Empire APPENDIX E STATISTICAL SEISMIC RISK EVALUATION O Seismicity represents a measure of past seismic activity or the effects of same in the site region or at the site. Such measures include the recurrence of magnitude, intensity, and horizontal ground acceleration. In the case of relatively stiff structures, peak horizontal ground accelerations are useful indicators of the effects of ground shaking and are significant in engineering practice. The statistical recurrence or probability of occurrence of various levels of ground motion based on past seismic activity can be determined using available sources of earthquake data and various methods of analysis. No single source of data or method of calculation has gained wide acceptance in practice since each procedure has certain limitations. It is not yet possible to accurately predict the future occurrence of earthquakes in time or space from past records of seismic activity. Realizing all of these shortcomings, it is our opinion that statistical seismicity analyses provide the most rational basis for evaluating the degree of risk associated with most design level earthquakes corresponding to a particular level of ground shaking. The following sections discuss the seismic risk models and results of our evaluation O of the recurrence intervals and probabilities of exceeding various levels of horizontal ground acceleration in the site region and at the site. Analyses were performed using the earthquake data and geologic evidence discussed earlier. For each model, earthquakes were assumed to have a Poisson distribution. Earthquake Data Records: Three earthquake data records were assembled to provide a basis for probabilistic seismic analyses. It is generally accepted that the seismograph records of earthquakes, which have only been recorded since 1932, are not sufficiently long to develop suitable statistical analyses of seismicity in Southern California. Therefore, seismograph data is augmented with both historic data and available geologic evidence. Each of these three data sets is described below: o Instrumental Earthquake Data (1934-1987): Instrumental earthquake data for 54 years, from 1934 to 1987, were obtained from the comprehensive listing of the California Institute of Technology Seismological Laboratory. This list is complete and accurate and well suited for statistical analysis. It should be recognized that this 54-year record represents a very short time in Southern California geologic and seismic history. O 89-81-165-01 Converse Consultants Inland Empire E-2 o Non-Instrumental Earthquake Data (1800-19331: Non-instrumental earthquake O data for 134 years, from 1800 through 1933, were obtained from Wood and Heck as revised by Eppley (1966). This catalog must be regarded as inaccurate and incomplete in several respects. Many of the smaller, and probably several larger, earthquakes which have occurred are missing; maximum Modified Mercalli intensities were reported in lieu of instrumental measurements (Richter magnitude); and corresponding epicentral locations are very approximate. The main advantage of this 134-year non-instrumental record is that it represents a time period about 2 1/2 times as long as the 54-year instrumental catalog. , Probabilistic Fault Model: A seismic fault model based on geologic evidence was developed assuming the occurrence of geologically credible earthquake events on regional faults including those listed in Table 4-1 at estimated recurrence intervals. The magnitude recurrence relationships developed for these faults are approximately based on analyses of limited direct geologic evidence and regional tectonics. The use of such a biased record represents an attempt to take into account thousands of years of known geologic evidence including fault locations, lengths and displacement rates. Seismic Risk Models: Computer analyses were performed using each of the three earthquake records described above to evaluate the probabilistic ground motions at the site. These analyses were performed for bedrock ground acceleration. O Probabilistic ground motions in bedrock are plotted on Figure 4.3, "100-Year Period Horizontal Ground Acceleration". The various methods of analyses plotted on Figures 4.3 are described below: Site Region: The site region model was based on methods outlined by Marachi and Dixon (1972), and calculations were performed considering earthquakes of the instrumental and non-instrumental catalogs occurring within a circular area around the site. This model assumes the random occurrence of earthquakes in space, the independence of events, and acceleration attenuation with distance from the earthquake based on curves by Seed and Idriss (1982) for bedrock. Results of this analysis should be regarded as an average for the site region. L al ite: The local site model assumed the independence of seismic events, and calculations were performed using-all earthquakes of the instrumental and historic records within a circular area around the site. Accelerations at the site were calculated for each event using the magnitude, epicenter-site distance and attenuation curves from Seed and Idriss (1982) for bedrock. Results of this analysis are strongly dependent upon the specific site location and should be regarded as unique to the site. O 89-81-165-01 Converse Consultants Inland Empire E-3 O o Fault Model: The fault model included the major faults listed in Table 4-1. Seismic characteristics of the faults were estimated based on direct geologic evidence, judgement and experience. Earthquakes were assumed to occur uniformly along the faults at estimated recurrence intervals. Accelerations at the site were determined using the minimum fault rupture distance and attenuation curves from Seed and Idriss (1982) for bedrock. Results of this analysis are, as for the local site model, strongly dependent upon the project location and should be regarded as unique to the site. These analyses were plotted on one graph for bedrock material (Figure 4.3). The number of occurrences exceeding a particular level of acceleration are plotted against the maximum peak horizontal ground acceleration. Aline was drawn on Figure 4.3 representing an integration of the various methods of analyses and earthquake data records, depicting CCIE's best judgement as to the 100-year probable ground motion in bedrock material at this site. O O 89-81-165-01 Converse Consultants Inland Empire