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Home My WebLink AboutCT 83-19; CALAVERA HEIGHTS VILLAGES W,X,Y; INTERIM REPORT OF GEOTECHNICAL INVESTIGATION; 1990-05-15UTTERIM REPORT CF (3X7IECHNICRL INVESnGfiTICN CALAVERA HEIGHIS VILLftGES W-X-Y TAMARACK AND CQLLEQE BCOCBVARD CARLSBAD, CALIPCWNIA PREPARED FOR: Lyon (jcniiimitu.es. Incorporated 4330 La Jolla Village Drive, Suite 130 San Diego, Califomia 92122 PREPARED BY: Sou1±em Califomia Soil & Testing, Irx:. Post Office Box 20627 6280 Riverdale S1u?eet San Diego, Califomia 92120 SOUTHERN CALIFORNIA SOIL AND TESTING, INC. eZBD mVERDALE ST. SAN D.EGO. CAUF. 92,20 • TELE 280-4321 • P.O. BOX 20627 SAM O.EBO. CAUr. 921 20 e V B ENTERPRISE ST. ESCONDIDO. C A U , T. 9 2 Q Z 6 TELE May 15, 1990 Lyon Communities, Incorporated 4330 La Jolla Village Drive Suite 130 San Diego, Califomia 92122 ATTENTION: Mr. George Haviar SCS&T 9021049 Report No. 1 SUBJE(rr: Interim Report of Geotechnical Investigation, Calavera Heights Villages W-X-Y, Tamarack and College Boulevard, Carlsbad, Califomia. GentlCTien: In accordance with your request, we have completed an interim geotechnical investigation for the subject project. We are presenting herewith our findings and reccumendations. In general, we found the site suitable for the proposed developnent provided the reconrendations presented in the attached report are followed. If you have any questions after reviewing the contents contained in the attached report, please do not hesitate to contact this office. This opportunity to be of professional service is sincerely appreciated. Respectfully submitted,^--,^ "TA^SOH/& i-TfeSTING, INC SOUIHEFN PDRNIA.' Daniel B. Adler, R.C.E. #36037 DBA:JRH:KAR;inw cc: (2) Submitted (4) Hunsater and Associates (1) SCS&T, Escondido SOUTHERN CALIFQFJNIA TABLE OF CONlliNiS Introduction and Project Description 1 Project Scope 2 Findings ^ Site Description General Geology and Subsurface Conditions 3 Geologic Setting and Soil Description 3 1) Basenent Complex-Jurassic Metavolcanics and Cretaceous Ciranitics (Jmv/Kgr) 4 2) Santiago Fonnation (Es) 5 3) Older Quatemary (Pleist(x:ene) Alluvium (Qoal) 5 4) Younger Quatemary (Hoiocene) Alluvium (Qyal) 5 Tectonic Setting 7 (Geologic Hazards 7 Groundshaking 8 Seismic Survey and Rippability Characteristics 8 CSeneral 8 Rippability Characteristic of (5ranodioritic Rock 12 Rippable Condition (0-4,500 Ft./Sec.) 12 Marginally Rippable Condition (4,500 Ft./Sec.-5,500 Ft./Sec) 13 Nonrippable Condition (5,500 Ft./Sec. & Greater) 13 Rippability Characteristics of Metavolcanics and Associated Hypabyssal Rocks and Tonalitic Rocks 13 Rippable Condition (0-4,500 Ft. /Sec.) 13 Marginally Rippable Condition (4,500-5,500 Ft./Sec.) 14 Nonrippable Condition (5,500 Ft.Sec. & Greater) 14 Seismic Traverse Limitations 14 Groundwater ^5 Conclusions and Reconrnendations 16 (feneral 16 Grading 1^ Site Preparation 17 Select Cirading • 17 Cut/Fill Transition 17 Inported Fill 18 Rippability 18 Oversized Rock 18 Slope Construction 18 Surface Drainage 18 Subdrains 19 Ecirthwork 19 Slope Stability 19 Foundations 19 General 19 Reinforcement 20 Interior Concrete Slabs-on-(3rade 20 Exterior Concrete Slabs-on-Grade 21 Special Lots 21 Expansive Characteristics 21 Settlement Characteristics 21 Earth Retaining Walls 22 Passive Pressure 22 Active Pressure 22 TABI£ OF CXJTTEOTS (continued) PACT: Backfill 22 Factor of Safety 22 Limitations 23 Review, Observation and Testing 23 Uniformity of Conditions 23 Change in Scope 23 Time Limitations 24 Professional Standard 24 Client' s Responsibility 24 Field Explorations 25 Laboratory Testing 25 ATEACHMEWrS TABLES Table I Table II Table III (Generalized Engineering Characteristics of C^logic Units, Page 6 The Maximum Bedrock Accelerations, Page 8 Seismic Traverse Summary, Pages 9 through 12 FIGURE Figure 1 Site Vicinity Map, Follows Page 1 FIAEES Plate Plate Plates Plate Plate Plate Plate Plate Plate Plate Plate Plates Plates 1 Plot Plan 2 Unified Soil Classification Chart 3-9 Trench Logs 10 (Grain Size Distribution 11 Conpaction Test Results Expansion Test Results 12 Direct Shear Sunmary 13 Oversize Rock Disposal 14 Canyon Subdrain Detail 15 Slope Stability Calculations 16 Weakened Plane Joint Det:ail 17 Retaining Wall Subdrain Detail 18-20 Seismic Line Traverses 21-23 Catepillar Rippability CJiarts APPQCIX Recommended (Grading Specification and Special Provisions SOUTHERN CALIFORNIA SOIL AND TESTING, INC. 62B0 RIVERDALE ST. SAN DIEGO. CALIF. 92,20 • TELE 280-432, • P.O. BOX 20627 SAN DIEGO. CALIF. 92,20 6VB ENTERPRISE SI ESCONDIDO. CALIF, 92DZ5 • TELE 7«S-45AA UnERIM REPORT OF GBCTTBCHNICAL INVESTIGATION CALAVERA HEIGHTS VILLAGES W-X-Y TAMARACK AND COLLEGE BOULEVARD CARLSBAD, CALIFORNIA INTRODUCTION AND PROJECT CESGRIPTION This report presents the results of our interim report of geotechnical investigation for Calavera Heights Subdivision, Villages W-X-Y, Tamarack and College Boulevard, in the City of Carlsbad, Califomia. The site location is illustrated on the following Figure Nuirber 1. It is our understanding that the site will be developed to receive a residential subdivision with asscxriated paved streets. It is anticipated that the structures will be one and/or two stories high and of wood frame construction. Shall(3w foundations and conventional slab-on-grade floor systems are proposed. Grading will consist of cuts and fills up to approximately 40 feet and 35 feet deep, respectively. Cut and fill slopes up to approximately 35 feet high at a 2:1 (horizontal to vertical) are also anticipated. To assist with the preparation of this report, we were provided with a gradmg plan prepared by Hunsaker and Associates dated December 6, 1989. In addition we reviewed our "Supplemental Soil Investigation, Calavera Hills Subdivision," dated October 6, 1988, "Report of Geotechnical Investigation, Village Q and T, Calavera Hills Subdivision," dated January 10, 1984, and SOUTHERN CALIFDRNIA SOIL AND TESTING, INC I i I '>'^^^?-»—..~--i.t>i!» ;^fta'l><;rVTf.ar=;=ii;ill h T-l:^^. -1 ~ r "'??n >v-H: if! t -7 : •' ii 'li'x^' ' -{I'S ....... I. SITE .1 <*» tOMa.a r.,..,,..-- . .. - '. . ^ Ar»t L' I SOUTMIIIN CALIFORNIA ^^^^ SOIL A TBSTINQ,INC. CALAVERAS HEIGHTS-VILLAGE BV: KAR/EM DATi: 5-15-90 FIGURE #1 SCS&T 9021049 May 15, 1990 Page 2 our "Sunmary of Geotechnical Investigation, Lake Calavera Hills," dated August 6, 1984. The site configuration, topography and approximate locations of the subsurface explorations are shown on Plate Number 1. PROJECT SCOPE This interim report is based on the review of the aforementioned preliminary report for the Calavera Hills Subdivision. A site specific report will be prepared at a later date v^^en further field investigation and analysis of laboratory data has been completed. For the purpose of this report appropriate field investigation and laboratory test data was extracted from the previously mentioned report. More specifically, the intent of this study was to: a) Describe the subsurface conditions to the depths influenced by the proposed construction. b) The laboratory testing performed in the referenced report was used to evaluate the pertinent engineering properties, including bearing capacities, expansive characteristics and settlement potential, of the anticipated materials v^ich will influence the development of the proposed siabject site. c) Describe the rippability characteristics of the existing rock. d) Define the general geology at the site including possible geologic hazards which could have an effect on the site development. e) Develop soil engineering criteria for site grading and provide recommendations regarding the stability of proposed cut and fill slopes. f) Address potential construction difficulties and provide recomtendations conceming these problems. SCS&T 9021049 May 15, 1990 Page 3 g) Recommend an appropriate foundation system for the type of structures anticipated and develop soil engineering design criteria for the recommended foundation design. FINDINQS SriE DESCRIPTIGN The subject site is an irregular shaped parcel of land, designated as Villages W, X and Y within the Calavera Heights development in Carlsbad, Califomia. The subject site covers approximately one hundred acres and is bounded on the south, east and north by undeveloped land and by residential housing and undeveloped land on the vest. Topographically, the site is located in hilly terrain with well developed, large, drainage courses with steep-sided slopes. Elevations range from approximately 325 feet (MSL) at the central northem property boundary to 90 feet (MSL) at the eastem boundary. The inclinations of the natural slopes are generally on the order of 1.5 to 1, horizontal to vertical, or flatter. Drainage is acconplished via sheetflow and tJie well developed drainage courses in southerly, easterly and northeasterly directions. Vegetation is conprised of sparse to very dense chaparral on the hillsides and dense native shrubs and small trees within the large drainage courses. Overhead power lines traverse the site in a southwest to northeast direction. The site is undeveloped, with the exception of the pov^r lines. CTWERAL CTXJLOGY AND SUBSURFACE OCNDITICNS GBUILOGIC SETTIN5 AND SOIL DESCRIPTION: The subject site is located near the boundary between the Foothills Physiographic Province and the Coastal Plains Physiographic Province of San Diego County and is underlain by materials of igneous and sedimentary origin and surficial residuum. The site is underlain by the basement ccnplex rocks consisting of Jurassic-age metavolcanic rocks. Cretaceous-age granitic rocVs, as well as Tertiary-age Santiago Formation and Quaternary-age alluviian. A brief description of the materials on-site, in general decreasing order of age, is presented below. SCS&T 9021049 May 15, 1990 Page 4 1) BASEMENT CCMPLEX - JURASSIC MEEAVOLCANICS AND CRETACECOS GRANITICS {Jmr/Kgr)z The oldest rocks exposed at the site are the Jurassic netavolcanic and associated hypabyssal rocks. The metavolcanic rocks are generally andesite or dacite in composition and the associated hypabyssal rocks are their porphyritic equivalents (ie: diorite porphyry to granodiorite porphyry). The fine grained hypabyssal rocks are considered to be about the same age as the metavolcanics and are consequently older than the other intrusive rocks found at the site. Both the netavolcanics and the associated hypabyssal rocks weather to dark, smooth hills or jagged, angular outcrops with a clayey, rocky topsoil. The metavolcanic and hypabyssal rocks are generally rippable with conventional earth-noving equipment to depths of only a few feet. The other rocks in the basement complex are the granitic rocks of the Cretaceous Southem Califomia Batholith which have intruded the older rocks and are, to a large degree, mixed with them. The granitic rxxrks at the project site appear to be both tonalitic and granodioritic in composition. The tonalitic rocks are usually dark gray, fine to nedivim grained rocks v^ereas the granodioritic rocks are usually yellowish brown to grayish brown, medium to coarse grained rocks. The weathering and rippability characteristics of the tonalitic rocks appear to be somewhat similar to those of the netavolcanic/hypabyssal rocks. The tonalitic rocks may be rippable to greater depths than the metavolcanic rocks but ripping may be difficult and time consimiing. In addition, it should be noted that the material generated from the tonalitic rocks will have the appearance of the metavolcanic rocks rather than that of good quality "decomposed granite". In contrast to the weathering characteristics of the metavolcanic/hypabyssal rock and the tonalitic rocks, the granodioritic rocks commonly weather to rounded outcrops or boulders in a matrix of grus ("decomposed granite"). The granodioritic rocks are variable in their excavation characteristics but commonly contain areas v*iich are rippable to SCS&T 9021049 May 15, 1990 Page 5 depths of several feet or several tens of feet, yet include localized areas of boulders or unweathered rock which are not rippable with conventional heavy equipment. The areas underlain by the respective rock types in the basonent complex are intermixed and are not differentiated on the accompanying geologic map. It should be noted that since the different rock types are mixed, the areas on the map v^iere given a dual classification. The boundaries between the basement rock types are very irregular, therefore they vere not differentiated on Plate Number 1. 2) SAMTIAQO PORMATICIN (Es): The Eocene sedinents at the project site are represented by the sandstones, siltstones, and claystones of the Santiago Formation. The Santiago Formation at the site appears to be characterized largely by the grayish white sandstones and siltstones with lesser amounts of the dark greenish brown claystone. A well-developed, clayey topsoil is present on nost of the Santiago Formation. 3) QLOER QUATERNARY (PLEISTOCENE) ALLUVIUM (Qoal): Older alluvial deposits consisting of grayish brown to yellowish brown and greenish brown, medium dense, silty sands, clayey sands, and sandy silts were encountered at the southeastem portion of the project site. These deposits range in thickness from only a few feet to in excess of ten feet. Smaller, un-mapped areas may be encountered at other scattered locations. 4) YOUNGER QUATERNARY (HOLOCENE) ALLUVIUM (Qyal): Younger alluvial deposits consisting of unconsolidated, loose to medium dense d^X3sits of clay, silt, sand, and gravel are present in the modem drainage courses. These deposits range in thickness from less than a foot to over ten feet. Due to their ubiquitous occurrence, the younger alluvial deposits are not delineated on the geologic map except in the larger channels. SCS&T 9021049 May 15, 1990 Page 6 A relatively thin layer of loose topsoils and si±)Soils should be anticipated overlying the entire site. These deposits consist of varying mixtures of silts, sands and clays. It is estimated that these deposits do not exceed 3.5 feet in contoined thickness. Table I presents some of the pertinent engineering characteristics of the materials at the site. TABLE I GENERALIZED ENGINEERING CHARACTERISTICS OF MAIN GESJUOGIC UNITS Unit Name and Synfcol Amoxmt of Slope Oversize Stability/ Rippability Material Erosion Compressibility Expansive Potential Granitic Rocks- Kgr (Granodiorite) Granitic Rocks- Kgr (Tonalite) Generally Rippable to + 15 Feet Marginally Rippable to Nonrippable Low to Good Moderate Moderate to Good High Nominal Nominal Nominal Nominal Metavolcanic and Hypabyssal Rocks-Jmv Marginally Rippable to Nbrurippable Moderate to High Good Nominal Nominal Santiago Formation-Es (Mudstone) Rippable Nominal Generally Poor Low Moderate to High Santiago Formation-Es (Sandstone and Siltstone) Rippable Nominal Generally Good Low Low to Moderate Older Alluvium-Qoal Rippable Nominal Moderately Erodible Moderate to Hiqh Low to Hiqh SCS&T 9021049 May 15, 1990 Page 7 TECTONIC SETTING: A few small, apparently inactive faults have been mapped previously within the vicinity of the site. No evidence of faulting was noted in our exploratory trenches for the referenced reports but it is possible that future grading operations at the site may reveal seme of these faults. Due to their status of activity and geometry, these small faults should be only of minor consequence to the project. It should also be noted that several prominent fractures and joints which are probably related, at least in part, to the strong tectonic forces that dominate the Southem Califomia region are present within the vicinity of the site. These features are usually near-vertical and strike in both a general northwesterly direction (subparallel to the regional structural trend) and in a general northeasterly direction (subperpendicular to the regional structural trend). All cut slopes should be inspected by a qualified geologist to assess the presence of adverse jointing conditions in the final slopes. In addition, it should be recognized that much of Southem Califomia, is ageracterized by major, active fault zones that could possibly affect the subject site. The nearest of these is the Elsinore Fault Zone, located approximately 20 miles to the northeast. It should also be noted that the possible off-shore extension of the Rose Canyon Fault Zone is located approximately eight miles west of the site. The Rose Canyon Fault Zone conprises a series of northvest trending faults that could possibly be classified cis active based on recent geologic studies. It is anticipated that the Rose Canyon Fault will be classified as active in the near future. Recent seismic events along a small portion of the Rose Canyon Fault Zone have generated earthquakes of 4.0 or less magnitude. Other active fault zones in the region that could possibly affect the site include the Coronado Banks and San Clemente Fault Zones to the vest, the Agua Blanca and San Miguel Fault Zones to the south, and the Elsinore and San Jacinto Fault Zones to the northeast. GBCOXXnC HAZARDS; The site is located in an area v^ch is relatively free of potential geologic hazards. Hazards such as tsiinamis, seiches, liquefaction, and landsliding should be considered negligible or nonexistent. SCS&T 9021049 May 15, 1990 Page 8 GROUNDSHAKING: One of the nost likely geologic hazards to affect the site is groundshaking as a result of movement along one of the major, active fault zones nentioned above. The maximum bedrock accelerations that would be attributed to a maximum probable earthquake occurring along the nearest portion of selected fault zones that could affect the site are sunmarized in the following Table II. TABLE II Fault Zone Rose Canyon Elsinore Coronado Banks San Jacinto Distance Maximum Probable Earthquake Bedrock 8 miles 20 miles 24 miles 43 miles 6.5 magnitude 7.3 magnitude 7.0 nagnitude 7.8 magnitude Design Acceleration Acceleration 0.36 g 0.23 g 0.25 g 0.17 g 0.18 g 0.12 g 0.14 g 0.10 g Earthquakes on the Rose Canyon Fault Zone are expected to be relatively minor. Major seismic events are likely to be the result of movement along the Coronado Banks, San Jacinto, or Elsinore Fault Zones. Experience has shown that structures that are constructed in accordance with the Uniform Building Code are fairly resistant to seismic related hazards. It is, therefore, our opinion that structural damage is unlikely if such buildings are designed and constructed in accordance with the minimum standards of the most recent edition of the Uniform Building Code. SEISMIC SURVEY AND RIPPABIUTY CHARACTERISTICS GENERAL: The results of our seismic survey and exploratory trenches performed for the referenced reports indicate that blasting will be required to obtain proposed cuts. In addition, isolated boulders are anticipated within cut areas that may require special handling during grading operations. A svntmary of each seismic traverse is presented in Table III SCS&T 9021049 my 15, 1990 Page 9 below, and Plates Number 18 through 20. Our interpretation is based on the rippability characteristics of granitic and metavolcanic rock as described in Pages 12 through 15. TABLE III Seismic Traverse No. S73-14 Proposed Cut: 48 Feet Geologic Unit: Metavolcanic Interpretation: 0'-15' Nonrippable Seismic Traverse No. SW-10 Proposed Cut: Geologic Unit: Interpretation: 50 Feet Metavolcanic 0'- 3' Rippable 3'-17' Rippable with Hardrock Floaters 17'-30' Nonrippable Seismic Traverse No. S?f-10R Proposed Cut: Geologic Unit: Interpretation: 50 Feet Metavolcanic 0'- 3' Rippable 3'-17' Rippable with Hardrock Floaters 17'-30' Nonrippable Seismic Traverse No. SW-11 Proposed Cut: None Geologic Unit: Metavolcanic Interpretation: 0'- 6' Rippable 6'-27' Nonrippable Seismic Tcaverse No. SW-llR Proposed Cut: None Geologic Unit: Metavolcanic Interpretation: 0'- 6' Rippable 6'-27' Nonrippable SCS&T 9021049 May 15, 1990 Page 10 TABLE III (continued) Seismic Traverse No. SW-12 Proposed Cut: Geologic Unit: Interpretation: 29 Feet Metavolcanic 0'- 6' Rippable 6'-21' Marginally Rippable with Hardrock Floaters -I- 21' Nonrippable Seismic Traverse No. SW-12R Proposed Cut: 29 Feet Geologic Unit: Metavolcanic Interpretation: 0'- 5' Rippable 5'- 26' Rippable with Hardrock Floaters + 26' Nonrippable Seismic Traverse No. SW-13 Proposed Cut: Geologic Unit: Interpretation: 13 Feet Jfetavolccinic 0'- 4' Rippable 4'-15' Rippable with Hardrock Floaters + 15' Nonrippable Seismic Traverse No. SW-14 Proposed Cut; Geologic Unit: Interpretation: 38 Feet tfetavolcanic 0'- 4' Rippable 4'-21' Rippable with Hardrock Floaters + 21' Nonrippable Seismic Tcaverse No. SW-14R Proposed Cut: Geologic Unit: Interpretation: 38 Feet Metavolcanic 0'- 3' Rippable 3'-14' Rippable with Hardrock Floaters 14'-30' Marginally Rippable with Hardrock Floaters SCS&T 9021049 May 15, 1990 Page 11 TABLE III (continued) Seismic Traverse No. SX-15 Proposed Cut: Geologic Unit: Interpretation: Unknown tfetavolcanic 0'- 6' Rippable 6'-15' EUppable with Hardrock Floaters -I- 15' Nonrippable Seismic Traverse No. SX-15R Proposed Cut: Geologic Unit: Interpretation: Unknown Metavolcanic O'-ll' Rippable 4- 11' Nonrippable Seismic Traverse No. SZl-16 Proposed Cut: Geologic Unit: Interpretation: None Granitic 0'-16' Rippable 16'-27' Rippable with Hardrock Floaters -I- 27' Nonrippable Seismic Traverse No. SZ1-16R Proposed Cut: None Geologic Unit: Metavolcanic/Granitic Interpretation: 0'-20' Rippable with Hardrock Floaters -I- 20' Nonrippable Seismic Traverse No. SZ2-17 Proposed Cut: Unknown Geologic Unit: Metavolcanic/Qranitic Interpretation: 0'- 5' Rippable + 5' Nonrippable I I SCS&T 9021049 May 15, 1990 Page 13 Materials within the velocity range of from 3,500 to 4,000 fps are rippable with difficulty by backhoes and other light trenching equipment. MARGINALLY RIPPABLE CONDITION (4,500 FT./SEC.-5,500 FT./SEC.): This range is rippable with effort by a D-9 in only slightly weathered granitics. This velocity range may also include numerous floaters with the possibility of extensive areas of fractured granitics. Excavations may produce material that will partially break down into a coarse, slightly silty to clean sand, but containing a high percentage of + 1/4" material. Less fractured or veathered materials may be found in this velocity range that would require blasting to facilitate removal. Materials within this velocity range are beyond the capability of backhoes and lighter trenching equipment. Difficulty of excavation would also be realized by gradalls and other heavy trenching equipment. NONRIPPABUE CODITKll (5,500 PT./SEC. & GREATER): This velocity range includes nonrippable material consisting primarily of fractured granitics at lower velocities with increasing hardness at higher velocities. In its natural state, it is not desirable for building pad subgrade. Blasting will produce oversize material requiring disposal in areas of nonstiructural fill. This upper limit has been based on the Rippability Chart shown on Plates Nunter 18 through 20 utilized for this report. However, as noted in the Caterpillar Chart on Plates Number 21 through 23, this upper limit of rippability may sonetines be increased to 7,000 to 8,000 fps material using the D-9 mounted #9 Series D Ripper. RTPPARTT.-rry CHARACTERISTICS OF MEEAVOLCANICS AND ASSOCIATED HYPABYSSAL ROCKS AND TCNALmC ROCKS RIPPABai: aWDmCN (0-4,soo FT./SBC.): This velocity range indicates rippable materials vMch may vary from deccirposed metavolcanics at SCS&T 9021049 May 15, 1990 Page 14 lower velocities to only slightly decomposed, fractured rock at the higher velocities. Although rippable, materials may be produced by excavation that will not be useable in structural fills due to a lack of fines. E}^rience has shown that material within the range of 4,000 to 4,500 fps most often consists of severely to moderately fractured angular rock with little or no fines and sizeable quantities of + 1/4" material. For velocities between 3,500 to 4,500 fps, rippability will be difficult for backhoes and light trenching equipment. MARGINALLY RIPPABLE CONDITION (4,500-5,500 FT./SEC-): Excavations in this velocity range would be extreneiy time consuming and would produce fractured rock with little or no fines. The higher velocities could require blasting. Trenching equipment would not function. NONRIPPABLE CCNDITICN (5,500 FT./SEC. & GREATER): This velocity range may include moderately to slightly fractvured rock which would require blasting for removal. Material produced would consist of a high percentage of oversize and angular rock. Rippability of metavolcanics may be accomplished for higher velocities using the Caterpillar D-9 with the #9 D Series Ripper. Due to the fractured nature of some metavolcanics, ripping might be acconplished in as high as 8,000 fps material. SEISMIC TRAVERSE UMTEVTICNS The results of the seismic survey for this investigation reflect rippability conditions only for the areas of the traverses. However, the conditions of the various soil-rock units appear to be similar for the remainder of the site and may be assumed to possess similar characteristics. SCS&T 9021049 May 15, 1990 Page 15 Our reporting is presently limited in that refraction seismic surveys do not allow for prediction of a percentage of expectable oversize or hardrock floaters. Subsurface variations in the degree of weathered rock to fractured rock are not accurately predictable. The seismic refraction nethod requires that materials become increasingly dense with depth. In areas where denser, higher velocity materials are underlain by lower velocity materials, the lover velocity materials vrould not be indicated by our survey. All of the velocities used as upper limits for rippability are subject to fluctuation depending upon such local variations in rock conditions as: a) Fractures, Faults and Planes of Weakness of Any Kind b) Weathering and Degree of Deccnposition c) Brittleness and Crystalline Nature d) Grain Size Further, the range of rippability using Caterpillar equipment may be increased using different equipment. However, it should be noted that ripping of higher velocity materials may become totally dependent on the tine available and the economics of the project. Ripping of higher velocity materials can be achieved but it may beccne economically infeasible. GROUNDWATER: No groundwater was encountered during our subsurface explorations for the referenced reports. Even though no major groundwater problems are anticipated either during or after construction of the proposed development, seasonal groundwater from precipitation runoff may be encountered within the larger drainage swales during grading for the developnent. It is suggested that canyon stibdrains be installed within drainage swales which are to receive fill. It should be realized that groundwater problens may occur after developnent of a site even where none were present before development. These are usually minor phenomena and are often the result of an alteration of the permeability characteristics of the SCS&T 9021049 May 15, 1990 Page 16 soil, an alteration in drainage pattems and an increase in irrigation water. Based on the permeability characteristics of the soil and the anticipated usage of the development, it is our opinion that any seepage problems which may occur will be minor in extent. It is further our opinion that these problems can be most effectively corrected on an individual basis if and v^en they develop. OONCLUSICNS AND RBODMMENDATICNS GEHERAL In general, no geotechnical conditions were encountered which would preclude the development of the site as tentatively planned, provided the recommendations presented herein are followed. The main geotechnical condition that will affect the proposed site developnent include hard granitic, metavolcanic, and hypabyssal rock, vihich will require heavy ripping and blasting in order to make the proposed excavations. It is anticipated that the material generated from the cuts of the granitic, netavolcanic and hypabyssal rock will contain relatively low amounts of fine soils and large amounts of oversized material. Since rock fills require a percentage of fine soil, mining of the site, irtporting of fine materials or exporting excess rock may be necessary. Existing loose surficial deposits such as topsoils, subsoils, younger alluvium, and any veathered formational materials encountered are considered unsuitable for the support of settlement sensitive improvements, and will require removal and/or replacenent as conpacted fill. Ejqjansive soils vere also present within the subject area. Where possible, select grading is reconmended to keep nondetirinentally expai\sive soils within four feet from finish pad grade. In areas vihere this is not feasible, special foundation consideration will be necessary. However, it is anticipated that only minor amounts of expansive soils will be encountered. SCS&T 9021049 May 15, 1990 Page 17 GRADING SITE PREPARKFICN: Site preparation should begin with the removal of any existing vegetation and deleterious matter from proposed inprovement areas. Removal of trees should include their root system. Any existing loose surficial deposits such as topsoils, subsoils, younger alluvium and any weathered formational materials, in areas to be graded should be removed to firm natural ground. The extent of the topsoils and subsoils will be approximately one to three and one half feet. Firm natural ground is defined as soil having an in-place density of at least 90 percent. Soils exposed in the bottom of excavations should be scarified to a depth of 12 inches, moisture conditioned and recompacted to at least 90 percent as determined in accordance with ASTM D 1557-78, Method A or C. The minimum horizontal limits of removal should include at least five feet beyond the perimeter of the structures, and all areas to receive fill and/or settlement-sensitive inprovements. SELECT GRADINS: Expansive soils should not be allowed within four feet from finish pad grade. In addition, expansive soils should not be placed within a distance from the face of fill slopes equal to ten feet or half the slope height, whichever is nore. Select material should consist of granular soil with an expansion index of less than 50. It is reconnended that select soils have relatively low permeability characteristics. In areas undercut for select grading purposes, the bottom of the excavation should be sloped at a minimum of three percent away from the center of the structure. Mininum lateral extent of select grading should be five feet away from the perimeter of settlement-sensitive inprovements. CUT/FILL UWNSinCN: It is anticipated that a transition line between cut and fill soils may run through some of the proposed building pads. Due to the different settlement characteristics of cut and fill soils, construction of a stmcture partially on cut and partially on fill is not recommended. Based on this, we recomrend that the cut portion of the building pads be undercut to a depth of at least three feet below finish grade, and the SCS&T 9021049 May 15, 1990 Page 18 materials so excavated replaced as uniformly compacted fill. The nunimum horizontal limits of these recomtendations should extend at least five feet outside of the proposed irtprovenents. IMPCanED FILL: All fill soil inported to the site should be granular and should have an expansion index of less that 50. Further, inport fill should be free of rock and lunps of soil larger than six inches in diameter and should be at least 40 percent finer than 1/4-inch. Any soil to be ijtported should be approved by a representative of this office prior to Importing. RIPPABnJTr: It is anticipated that the proposed cuts will require heavy ripping and blasting. Plates Nunter 18 through 20 contain the results of our seismic traverses. The results are simmarized within this report. This condition will be further evaluated during the preparation of the geotechnical investigation report. Additional seismic traverses will be perfomed in areas where deep cuts are proposed. OVERSIZED ROCK: Oversized rock is defined as material exceeding six inches in maximum dimension. It is anticipated that oversized material will be generated from proposed cuts. Oversized material may be placed in stmctural fills as described in Plate Nunter 13. SLOPE CONSTRUCTION: The face of all fill slopes should be conpacted by backrolling with a sheepsfoot compactor at vertical intervals no greater than four feet and should be track walked v^ien conpleted. Select grading should be performed to limit expansive soils within ten feet from face of fill slope or one half the slope height, whichever is greater. Recommendations contained within this report reflect a select grading condition. All cut slopes should be observed by our engineering geologist to verify stable geologic conditions. Should any unstable conditions be found, mitigating measures could be required. SURFACE DRAINAGE: It is recaimended that all surface drainage be directed away from the structures and the top of slopes. Ponding of water should not be allowed adjacent to the foundations. SCS&T 9021049 May 15, 1990 Page 19 SUBDRAINS: A subdrain should be installed in canyon areas to receive fill in excess of ten feet. A subdrain detail is provided in Plate Number 14. EARfflWCWK: All earthwork and grading contenplated for site preparation should be acconplished in accordance with the attached Recommended Grading Specifications and Special Provisions. All special site preparation reconrnendations presented in the sections above will supersede those in the Standard Recomtended Grading Specifications. All embankments, stmctural fill and fill should be conpacted to at least 90% relative conpaction at or slightly over optimum noisture content. Utility trench backfill within five feet of the proposed stmctiures and beneath asphalt pavements should be conpacted to minimum of 90% of its maximum dry density. The upper twelve inches of subgrade beneath paved areas should be compacted to 95% of its maximum dry density. This compaction should be obtained by the paving contractor just prior to placing the aggregate base material and should not be part of the mass grading requirements. The maximum dry density of each soil type should be determined in accordance with ASTM Test Method D-1557-78, Method A or C. SLOPE SraRTTiTTY Proposed cut and fill slopes should be constmcted at a 2:1 (horizontal to vertical) or flatter inclination. It is estimated that cut and fill slopes will extend to a maximum height of about 35 feet. It is our opinion that said slopes will possess an adequate factor of safety with respect to deep seated rotational failure and surficial failure (see Plate Number 15). The engineering geologist should observe all cut slopes during grading to ascertain that no adverse conditions are encountered. FOUNQAnONS (3MERAL: If the lots are capped with nondetrimentally expansive soils, conventional shallow foundations may be utilized for the support of the proposed structures. The footings should have a minimum depth of 12 inches SCS&T 9021049 May 15, 1990 Page 20 and 18 inches below lowest adjacent finish pad grade for one-and-two-story constmction, respectively. A minimum width of 12 inches and 18 inches is recomtended for continuous and isolated footings, respectively. A bearing capacity of 2000 psf may be assumed for said footings. This bearing capacity may be increased by one-third v^en considering wind and/or seismic forces. Footings located adjacent to or within slopes should be extended to a depth such that a minimum distance of six feet and seven feet exist between the footing and the face of cut slopes or fill slopes, respectively. Retaining walls in similar conditions should be individually reviewed by this office. If it is found to be unfeasible to cap the lots with nondetriitentally expansive soils as reconmended, special foundation and slab design will be necessary. This generally consists of deepened and more heavily reinforced footings, thicker, more heavily reinforced slabs. Recomtendations for expansive soil conditions will be provided after site grading v*ien the expansion index and depth of the prevailing foundation soils are known. REINPCWCEMEMr: Both exterior and interior continuous footings should be reinforced with at least one No. 4 bar positioned near the bottom of the footing and one No. 4 bar positioned near the top of the footing. This reinforcement is based on soil characteristics and is not intended to be in lieu of reinforcenent necessary to satisfy stmctiural considerations. If expansive soils exist within four feet of finish grade, additional reinforcing will be necessary. INTERIOR CONCRETE ON-GRADE SLABS: If the pads are capped with nondetrinentally expansive soils, concrete on-grade slabs should have a thickness of four inches and be reinforced with at least No. 3 reinforcing bars placed at 36 inches on center each way. Slab reinforcenent should be placed near the middle of t:he slab. As an altemative, the slab reinforcing may consist of 6"x6"-W1.4xW1.4 (6"x6"-10/10) welded wire mesh. However, it should be realized that it is difficult to maintain the proper position of wire nesh during placement of the concrete. A four-inch-thick layer of clean, coarse sand or crushed rock should be placed under the slab. This SCS&T 9021049 May 15, 1990 Page 21 layer should consist of material having 100 percent passing the one-half-inch screen; no more than ten percent passing sieve #100 and no more than five percent passing sieve #200. Where moisture-sensitive floor coverings are planned, the sand or rock should be overlain by a visqueen moisture barrier and a two-inch-thick layer of sand or silty sand should be provided above the visqueen to allow proper concrete curing. EXTERICai SLfiBS-<»-0»DE: For nonexpansive soil conditions, exterior slabs should have a minimum thickness of four inches. Walks or slabs five feet in width should be reinforced with 6"x6"-W1.4xW1.4 (6"x6"-10/10) velded wire mesh and provided with weakened plane joints. Any slabs between five and ten feet should be provided with longitudinal weakened plane joints at the center lines. Slabs exceeding ten feet in width should be provided with a weakened plane joint located three feet inside the exterior perimeter as indicated on attached Plate Number 16. Both traverse and longitudinal weakened plane joints should be constmcted as detailed in Plate Number 16. Exterior slabs adjacent to doors and garage openings should be connected to the footings by dowels consisting of No. 3 reinforcing bars placed at 24-inch intervals extending 18 inches into the footing and the slab. SPECIAL LOTS: Special lots are defined as lots underlain by fill with differential thickness in excess of ten feet. The following increased foundation recommendations should be utilized for said lots. Footings should be reinforced with two No. 4 bars positioned near the bottom of the footing and two No. 4 bars positioned near the top of the footing. Concrete on grade slabs should be reinforced with at least No. 3 reinforcing bars placed at 18 inches on center each way. Lots with fill differentials in excess of thirty feet should be evaluated on an individual basis. EXPANSIVE CHARACTERISTICS: Metavolcanic rock generally weathers to a clayey subsoil, and its presence within four feet of finish pad grade will require special site preparation and/or foundation consideration. SETTLHlHfP CHBRACIERISnCS: The anticipated total and/or differential settlenents for the proposed stmctures may be considered to be witMn SCS&T 9021049 May 15, 1990 Page 22 tolerable limits provided the recomiendations presented in this report are followed. It should be recognized that minor hairline cracks on concrete due to shrinkage of constmction materials or redistribution of stresses are normal and may be anticipated. EARra RETAINING WALLS PASSIVE PRESSURE: The passive pressure for the prevailing soil conditions may be considered to be 450 pounds per square foot per foot of depth up to a maximum of 2000 psf. This pressure may be increased one-third for seismic loading. The coefficient of friction for concrete to soil may be assumed to be 0.35 for the resistance to lateral novement. When combining frictional and passive resistance, the former should be reduced by one-third. The upper 12 inches of exterior retaining wall footings should not be included in passive pressure calculations when landscaping abuts the bottom of the wall. ACTIVE PRESSURE: The active soil pressure for the design of unrestrained earth retaining stmctures with level backfills may be assumed to be equivalent to the pressure of a fluid weighing 35 pounds per ci±>ic foot. For 2:1 (horizontal to vertical) sloping backfills, 14 pcf should be added to the preceding values. These pressures do not consider any surcharge. If any are anticipated, this office should be contacted for the necessary increase in soil pressure. This value assumes a drained backfill condition. Waterproofing details should be provided by the project architect. A subdrain detail is provided on the attached Plate Number 17. BACKFIUJ: All backfill soils should be conpacted to at least 90% relative conpaction. Expansive or clayey soils should not be used for backfill material. The wall should not be backfilled until the masonry has reached an adequate st:rength. FflCTPOR OF SAFETY: The above values, with the exception of the allowable soil bearing pressure, do not include a factor of safety. Appropriate factors of safety should be incorporated into the design to prevent the walls from overtuming and sliding. SCS&T 9021049 May 15, 1990 Page 23 LIMITATIONS REVIEW, OBSERVAnCN 2VND TESTING The recomtendations presented in this report are contingent upon our review of final plans and specifications. Such plans and specifications should be made available to the geotechnical engineer and engineering geologist so that they may review and verify their compliance with this report and with Chapter 70 of the Uniform Building Code. It is reconnended that Southem Califomia Soil & Testing, Inc. be retained to provide continuous soil engineering services during the earthwork operations. This is to verify compliance with the design concepts, specifications or recomtendations and to allow design changes in the event that subsurface conditions differ from those anticipated prior to start of constmction. UNlJrXJKMlTY OF OdOrnCWS The reconmendations and opinions expressed in this report reflect our best estimate of the project requirements based on an evaluation of the subsurface soil conditions encountered at the subsurface exploration locations and on the assunption that the soil conditions do not deviate appreciably from those encountered. It should be recognized that the performance of the foundations and/or cut and fill slopes may be influenced by undisclosed or unforeseen variations in the soil conditions that may occur in the intermediate and unexplored areas. Any unusual conditions not covered in this report that nay be encountered during site development should be brought to the attention of the geotechnical engineer so that he may make modifications if necessary. CHANGE IN SGCIPE This office should be advised of any changes in the project scope or proposed site grading so that we may determine if the recommendations contained herein are appropriate. This should be verified in writing or nodified by a vnritten addendum. SCS&T 9021049 May 15, 1990 Page 24 TIME LIMITATICNS The findings of this report are valid as of this date. Changes in the condition of a property can, however, occur with the passage of time, v^ether they be due to natural processes or the vork of man on this' or adjacent properties. In addition, changes in the Standards-of-Practice and/or Govemnent Codes may occur. Due to such changes, the findings of this report may be invalidated wholly or in part by changes beyond our control. Therefore, this report should not be relied upon after a period of two years without a review by us verifying the suitability of the conclusions and reconmendations. PROFESSIONAL STANDARD In the perfomance of our professional services, we coitply with that level of care and skill ordinarily exercised by members of our profession currently practicing under similar conditions and in the same locality. The client recognizes tJiat subsurface conditions may vary from those encountered at the locations where our trenches, surveys, and explorations are made, and that our data, interpretations, and recomiendations are based solely on the information obtained by us. We will be responsible for those data, interpretations, and reconmendations, but shall not be responsible for the interpretations by others of the information developed. Our services consist of professional consultation and observation only, and no warranty of any kind whatsoever, express or implied, is made or intended in connection with the work performed or to be performed by us, or by our proposal for consulting or other services, or by our fumishing of oral or written reports or findings. CLIEKT'S RESPGNSIBILITy It is the responsibility of Lyon Communities Incorporated, or their representatives to ensure that the information and reconmendations contained herein are brought to the attention of the stmctural engineer and architect SCS&T 9021049 May 15, 1990 Page 25 for the project and incorporated into the project's plans and specifications. It is further their responsibility to take the necessary neasures to insure that the contractor and his subcontractors carry out such reconmendations during constmction. FIELD EXPLORATIONS Three subsurface trench explorations vere made at the locations indicated on the attached Plate Number 1 on December 21, 1982, and three on July 7, 1983, adjacent to or within the subject site (see Plates Nuitter 3 through 6). In addition. Plates Nunter 7 through 9 from the referenced reports contain additional trench excavations made in Decenter 15, 1982, of similar soils within the subject subdivision. These explorations consisted of trenches dug by the neans of a backhoe. One seismic traverse was performed on April 14, 1973 and eight were performed on January 11, 1983. The field work was conducted under the observation of our engineering geology personnel. The results are shown on Plates Number 18 through 20. The soils are described in accordance with the Unified Soils Classification System as illustrated on the attached sinplified chart on Plate 2. In addition, a verbal textural description, the wet color, the apparent moisture and the density or consistency are provided. The density of granular soils is given as either very loose, loose, medium dense, dense or very dense. The consistency of silts or clays is given as either very soft, soft, medium stiff, stiff, very stiff, or hard. LABORATORY TESTING Laboratory tests vere performed in accordance with the generally accepted American Society for Testing and Materials (ASTM) test methods or suggested procedures. A brief description of the tests performed is presented below: a) CLASSIFICATICN: Field classifications were verified in the laboratory by visual examination. The final soil classifications are in accordance with the Unified Soil Classification System. SCS&T 9021049 May 15, 1990 Page 26 b) WDISTURE-rauSITY: In-place moisture contents and dry densities were determined for representative soil sanples. This information was an aid to classification and permitted recognition of variations in material consistency with depth. The dry unit weight is determined in pounds per cubic foot, and the in-place noisture content is determined as a percentage of the soil's dry- weight. The results are simitarized in the trench logs. c) OUON SIZE DISTRIBUnCN: The grain size distribution was determined for representative sanples of the native soils in accordance with ASTM D422. The results of these tests are presented on Plate Nunter 10. d) CCMPJCTION TEST: The naximum dry density and optimum noisture content of typical soils vere determined in the laboratory in accordance with ASTM Standard Test D-1557-78, Method A. The results of these tests are presented on the attached Plate Number 11. e) EXPANSION TEST: The expansive potential of clayey soils was determined in accordance with the following test procedure and the results of these tests appear on Plate Nunter 11. Allow the trimmed, undisturbed or remolded sample to air dry to a constant moisture content, at a temperature of 100 degrees F. Place the dried sanple in the consolidometer and allow to compress under a load of 150 psf. Allow noisture to contact the sample and measure its expansion from an air dried to saturated condition. f) DIRECT SHEAR TESTS: Direct shear tests vere perfomed to determine the failiure envelope based on yield shear st:rength. The shear box was designed to accommodate a ssmple having a SCS&T 9021049 May 15, 1990 Page 27 dianeter of 2.375 inches or 2.50 inches and a height of 1.0 inch. Sanples vere tested at different vertical loads and a saturated moisture content. The shear stress was applied at a constant rate of strain of approxinately 0.05 inches per minute. The average shear strength values for granitic and netavolcanic rock are presented on attached Plate Number 12. SUBSURFACE EXPLORATION LEGEND UNIFIED SOIL CLASSIFICATION CHART SOIL DESCRIPTION GROUP SYMBOL TYPICAL NAMES I. COARSE GRAINED, more than half of material is larger than No. 200 sieve size. GRAVELS CLEAN GRAVELS GW Well graded gravels, gravel- More tnan half of sand mixtures, little or no coarse fraction is fines. larger than No. 4 GP Poorly graced gravels, gravel sieve size but sand mixtures, little or no smaller than 3". fines. GRAVELS WITH FINES GM Silty gravels, poorly graded (Appreciable amount gravel-sand-silt mixtures. of fines) GC Clayey gravels, poorly graded gravel-sand, clay mixtures. SANDS CLEAN SANDS SW Well graded sand, gravelly More than half of sands, little or no fines. coarse fraction is SP Poorly graded sands, gravelly smaller than No. 4 sands, little or no fines. sieve size. SANDS WITH FINES SM Silty sands, poorly graded (Appreciable amount sand and silty mixtures. of fines) SC Clayey sands, poorly graded sand and clay mixtures. II. FINE GRAINED, more than half of material is smaller than No. 200 sieve size. SILTS AND CLAYS ML Inorganic silts and very fine sands, rock flour, sandy silt or clayey-silt-sand mixtures with slight plas- ticity. Liquid Limit CL Inorganic clays of low to less than 50 medium plasticity, gravelly clays, sandy clays, silty clays, lean clays. OL Organic silts and organic silty clays or low oiasticity. SILTS AND CLAYS MH Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts. Liquid Limit CH Inorganic clays of high greater than 50 plasticity, fat clays. OH Organic clays of medium to high plasticity. HIGHLY ORGANIC SOILS PT Peat and other highly organic soils. — Water level at time of excavation or as indicated US — Undisturbed, driven ring sample or tube sample CK — Undisturbed chunk sample BG — Bulk sample SP — Standard penetration sample SOUTHERN CALIFORNIA SOIL A TESTINQ, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y SOUTHERN CALIFORNIA SOIL A TESTINQ, INC. BY: KAR/EM DATE: 5-03-90 SOUTHERN CALIFORNIA SOIL A TESTINQ, INC. JOB NUMBER: 9021049 Plate No. 2 I I I I I Class TRENCH :;o. rT-50 Descriucion SM Gray-brown, Moist, Dense co Very Dense, Siltv Sand (Decomposed Granine) Trench Ended ac 4 Feet y/\ SOUTHERN CALIFORNIA XSUS SOIL & TESTING , INC. SAN oiaaa, CAUIPORNIA ••IBO CALAVERA HEIGHTS -VILLAGE W-X-Y BY CRB DATE 12-21-82 JOB NO. 9021049 Plate No. 3 1 •/• SC CL LO Claver . Red-brov.Ti, ...;isc. .-eaium jense. 3 c i i ',' Veilov;-broi>m , .'.^ia-b rown. J rav-orc^^m. ;!oisc, Ilediuui Dense. Clavev Silcv Sand, Porous (Older .llluvium) Sandv Clav/Clavev Sand Trencn Endea ac 10 Feec 113. 3.0 107.8 15.5 I SOUTHERN CALIFORNIA SOIL & TESTING , INC. • AN OiaaO, CAkiraMNIA ••IBO CALAVERA HEIGHTS-VILLAGE W-X-Y BY :RB JOB NO. 9021049 DATE 12-21-82 Plate 'Jo. 4 1 I I I ass e s c ri m c n S".'/ r.ec-orown. :'.cisc. -'.laaiurr. j^inse. ; ^ 1 S .ina i " :nsoi i ) SM ^avev :e^±ow ana urav-bro\m, i.jisc. Dense co Verv Dense, Silcy Sand vCecomnosed Cranice) Trench Ended ac 3 Feet [<^X SOUTHERN CALIFORNIA SL2S SOIL & TESTING , INC. 1 •••B HIVaNOAi.^ •TMBBT SAM OIKlia, CAklPOMNIA ••IBO CALAVERA HEIGHTS-VILLAGE W-X-Y BY CRB DATE ^, 12-21-82 JOB NO. 9021049 Plate No. 5 LU Q. < z o < -1 o o t to TRENCH NUMBER TX-77 ELEVATION • ESCRIPTION H Ul K t- < W a. — Q. O < z £ ^ t lU <0 0= ,« =^ «r UJ a O o o CO z _ UJ — > cc Q Ui C 3 H M O z IU Z o o UJ > z o o < a. Z o o GM BROWN SANDY GRAVEL (TOPSOIL) HUMID/ MOIST MEDIUM DENSE 2_ GM GRAY BROWN SANDY GRAVEL (METAVOLCANIC ROCK) HUMID VERY DENSE REFUSAL AT 2.5' TX-78 CL BROWN SILTY CLAY (TOPSOIL) MOIST STIFF GM GRAY BROWN SANDY GRAVEL (METAVOLCANIC ROCK) HUMID VERY DENSE REFUSAL AT 3' TRENCH NUMBER X-79 CL BROWN SILTY CLAY (TOPSOIL) MOIST STIFF GM GRAY BROWN SANDY GRAVEL (METAVOLCANIC ROCK) HUMID VERY DENSE REFUSAL AT 3' SUBSURFACE EXPLORATION LOG LOGGED BY: DATE LOGGED:^ , 7-18-83 JOB NUMBER: 9021049 Plate No. 6 SOUTHERN CALiFORNIA SOIL &TESTiNG,INC. I TRENCH NUMBER 2. I 2 < < I O I • EECHIPTICN oc < tf) Q. — X O < Z X < a. < al 05 Z '±1 a y) c O '•ft z _ UJ — Q u X Q i 3: 5 z z o u Ui o o < a. Z o u :SM/Sa RED BROWN. CLAYEY SILTY i SAND (TOPSOIL) RED, BROWN. GRAY, SANDY CLAY (WEATHERED DECOMPOSED GRANITE) YELLOW BROWN, SILTY GRAVELY SAND (DECOMPOSED GRANITE) MOIST TO WET WET MOIST MEDIUM DENSE MEDIUM STIFF DENSE TO VERY DENSE REFUSAL AT 3' TRENCH NUMBER TQ-2 SM/SL BROWN CLAYEY SILTY SAND (TOPSOIL) MOIST ML GREEN BROWN, SANDY SILT MOIST MEDIUM DENSE STIFF 4-'SM/ML BG YELLOW. RED, BROWN, SILTY SAND (WEATHERED DECOMPOSED GRANITE) MOIST MEDIUM DENSE SM 6- YELLOW BROWN, SILTY SAND (DECOMPOSED GRANITE) MOIST MEDIUM DENSE TO DENSE 121 .9 12.1 VERY DENSE TRENCH ENDED AT 8' SOUTHERN CALIFORNIA SOIL ATESTING,INC. SUBSURFACE EXPLORATION LOG LOGGED BY: CRB DATE LOGGED: 12-15-82 JOB NUMBER: 9021049 Plate No. 7 — ( f TRENCH NUMBER < I w i a. UJ C - 15 ; ; E^EVAT;-N 2 I < I < • ES'ZP.l — cc JJ — X Z < « Q. — a. O < S < a. a. < z C OJ tf) tf) a O o cn z _ Ul — >- X a CO 5 z z o UJ > Ui X z O a z o o [ 2 3 4 J BAGSM/SC c;< I RED BROWN. CLAYEY SILTY SAND (TOPSOIL) MOIST MEDIUM DENSE CK SM 6. 7 CK YELLOW BROWN, SILTY SAND (DECOMPOSED GRANITE) MOIST DENSE TO VERY DENSE 118.2 10.8 0-( TRENCH ENDED AT 8' TRENCH NUMBER ~0-7 1-CK SM RED BROWN. SILTY SAND (TOPSOIL) MOIST MEDIUM DENSE — 2^ SM DARK GRAY, GRAVELY SILTY SAND (DECOMPOSED GRANITE) MOIST DENSE TO VERY DENSE — TRENCH ENDED AT 2' — — - /Q^ SOUTHERN CALIFORNIA SOIL A TESTING,INC. SUBSURFACE EXPLORATION LOG /Q^ SOUTHERN CALIFORNIA SOIL A TESTING,INC. LOGGED BY: DATE LOGGED: 12-15-82 /Q^ SOUTHERN CALIFORNIA SOIL A TESTING,INC. JOB NUMBER: 9021049 Plate No. 8 -I i I I 1 - ll 2-! s f r: ^ ! T R ENC H NUMBER z- . - ; < . , U 2 : • - r ! _ _ 1 X i ; 1 3 - • A , < tf) ; i < ! ! ! ! ^ ^ ' ^ i OEECRiPTlCN 1 > 01 al (/) <= ^ ^ < 'JJ X « a < s § CJ DRY DENSIIY Ipcll MOISTURE CONTENT I'v-I RELATIVE COMPACIlOrJlM SM/ 1 RED BROWN. CLAYEY SILTY SC I SAND (TOPSOIL) MOIST MEDIUM DENSE — GM 1 BAGI 1 4 GRAY, SANDY GRAVEL (METAVOLCANIC ROCK) MOIST DENSE TO VERY DENSE - TRENCH ENDED AT 5' TRENCH NUMBER TQ-9 SM/ SC CL SM CK BAg RED BROWN, CLAYEY SILTY SAND (TOPSOIL) GRAY BROWN, SANDY CLAY (WEATHERED DECOMPOSED GRANITE) MOIST MEDIUM DENSE MOIST STIFF YELLOW BROWN, SILTY SAND (DECOMPOSED GRANITE) MOIST DENSE TO VERY DENSE 128.1 10.1 TRENCH ENDED AT 6' SOUTHERN CALIFORNIA SOIL A TESTING,INC. SUBSURFACE EXPLORATION LOG LOGGED BY: DATE LOGGED: ^ 2-1 5-82 JOB NUMBER: 9021049 Plate No.. 9 o > z (/) N m o m c H O z vo o ro • o Ol rt- n> o o I 00 o 2 5 o I— •< m CD LO I > I X I -< 36- loorj-r 90 so 70 § 60 so S 40 u t 30 20 10 1000 18" 24* IZ' 6" 4 S 84 i6o US Standard Sieves y |- Kz" •lO "20 *»0 1 21 1 4 S Hydromet er (Minutas) ?3y. .!!.sq_ "IOO _»20Q_ 12* M 440 / 3l> tl » > »« ? « I Grain Size (mm) t»7« $41 2 |44U t lOu 94 ? a 1 4 1 2 1)0 80 70 ^ 3 20 — f. b 10 — <> o PARTICLE SIZE LIMITS 1 BOULDER!COBBLES 1 GRAVEL SANO SILT OR CLAY 1 BOULDER!COBBLES 1 Coon* 1 Fin* Coart* 1 Madium | Fln« SILT OR CLAY (12 in.) 3 in. 3/4 in. U. S. No.4 No.lO STANDARD No.40 SIEVE SIZE TQ-2 @ 3' —— TQ-2 0 4'-5' — . . TQ-8 0 4'-5' -I- I MAXIMUM DENSITY & OPTIMUM MOISTURE CONTENT ASTM D1557-73 METHOD A ri •-.AMPLE DESCRIPTION Maximum Density (pcti Optimum Moisture Cont (•/.) J>1 3 2'-3' Yellow Brown, Silty Gravelly Sand 114.8 13.8 TG-2 '$ 2'-3' Green Brown, Sandy Silty Clay 114.0 15.0 |3-2 @ 4'-5' 1 Yellow/Reddish Brown, Silty Sand 112.6 14.8 -3-3 0 3'-4' j Grey, Silty Sandy Gravel 128.4 11.7 1 I I It EXPANSION TEST RESULTS I SAMPLE TQ-: L-) 2'-3' TQ-2 @ 3'-4' CONDITION Remolded Remolded NITIAL "^.C.C/.) lu.l 14.8 t NITIAL 2ZNSITY CPCH 101. 101.8 INAL M.C. (•/.) 30.5 26.0 E T I I NORMAL STRESS (PSF) .50 150 EXPANSION % SOUTHERN CALIFORNIA CALAVERA HEIGHTS-VILLAGE W-X-Y 1^^^ SOIL A TESTING, INC. BY: KAR DATE: 1-10-84 1^^^ SOIL A TESTING, INC. JOB NUMBER: 9021049 Plate No. 11 t DIRECT SHEAR SUMMARY I CO CO (n Ul s H < UJ X (O 2 3 2M L 2L NORMAL STRESS, KSF SAMPLE OESCRlPTION ANQLE OF INTERNAL FRICTION (•) COHESION INTERCEPT TQ-8@3'-4' Remolded to 90% 38 200 f |yV SOUTHERN CALIFORNIA CALAVERA HEIGHl rS-VILLAGE W-X-Y 1^^^ SOIL A TESTINQ,INC. •T: KAR OATE: 5-01-90 1^^^ SOIL A TESTINQ,INC. JOBNUMSBR: 9021049 Plate No. 12 I O r H m H Z O z o (A o c H Z Pi 31 O > r O 9 u CB O • z c s • kTAR o m kTAR > a r-H 1 f 1 AVI vo m o ro i» I—• o ZC m vo tn n: vo tn n: —1 o CO > 1 la H < la m 1—( r+ m 1— n> LA CD o CJl m 1 O s: 1—' OO 1 CJ 1 vo X o -< ( Siruclurul Soil - Rock fill ) P/L ^ ' Si h^S^ ZONE D • ^ T 3 min. urr P . 12' 'niin. * nns Coap«ct«d tell fill IMII CMIIIH tt Itot 40 ptrctnt soli llm H*><M IM-Uck ll*t«, (by atltlit). tntf ht cea^«ct*4 U •cc«r<««u xlU t^tciricttloni for itriicural fill. Itckl •*•< 4 fttt In atalM tftaMitlon not ptraltttd I* nil. Inchet In tjreiltil l(G(NO I0N£ 4; Comf>tcie<i toll fill, ho rock (rigmcnli over t diixni ion. IUN( I: Refill 2 lo 4 feci In aolnuM dlaentlon pitccd In CiMp«cled ioli rill conrtirMin, lo iONC A. lONC C: Rockt ( Indict lo t feet In m»i\mum Olawntlon uniforaly dlttrlbu- • cd ind MCll tp«<:cd In compicltd toll (III cotiforaing lo lOlt A. tONt 0: Ncqulrcd for «ll calilln, tlopet i:l 4nd ticeptr. 90t alnlnjin coi^i4Cllon. lONC A, B, or C atterUI aty bc utcd for ZONf 0. NATURAL/ GROUND > CANYON SUBDRAIN DETAIL 77^7777777777777//// / / / COMPACTED FILL / '/ / BENCHING ^ .^ZZi^'<^^/Vy/7/7///^^ • u:lO/////////^jl^ REMOVE UNSUITABLE MATERIAL SUBDRAIN TRENCH: SEE DETAIL AAB DETAIL A FILTER MATERIAL '6 CUBIC FEET/FOOT FILTER MATERIAL SHALL BE CLASS 2 PERMEABLE MATERIAL PER STATE OF CALIFORNIA STANDARD SPECIFICATIONS, AND APPROVED ALTERNATE. CLASS 2 FILTER MATERIAL SHOULD COMPLY WITH THE FOLLOWINQ LIMITS DETAIL A-1 PERFORATED PIPE 4 0 MINIMUM DETAIL A-2 PERFORATED PIPE SURROUNDED WITH FILTER MATERIAL SIEVE SIZE 1 3/4 3/S No. 4 No. 8 N«. 30 N«. 60 No. 200 % PASSING 100 90-100 40-100 2S-40 18-33 5-1B 0-7 O-S DETAIL B « MIN OVERLAP FILTER FABRIC (MIRAFI 140 OR APPROVED EQUIVALENT) DETAIL \ 1 1/2 MAX QRAVEL OR / DETAIL 8-1 APPROVED EQUIVALENT B-2 e CUBIC FEET/FOOT 1 1/2" QRAVEL WRAPPED IN FILTER FABRIC SUBDRAIN INSTALLATION:SUBDRAiN PIPE SHALL BE INSTALLED WITH PERFORATIONS DOWN SUBDRAIN PIPE'-SUBDRAIN PIPE SHALL BE PVC OR ABS, TYPE SDR 35 FOR FILLS UP TO 35 FEET DEEP, OR, TYPE SDR 21 FOR FILLS UP TO 100 FEET DEEP y\ SOUTHERN CALIFORNIA SOIL A TESTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y y\ SOUTHERN CALIFORNIA SOIL A TESTING, INC. BY: KAR DATE: 5-03-90 y\ SOUTHERN CALIFORNIA SOIL A TESTING, INC. JOB NUMBER: 9021049 Plate No. 14 SLOPE ETABILI'Y CALCULATIONS Janbu's Simolifiea Slooe Stability Method \C(?)zWH Tang) FS = Ncf(-C WH -} Assume Homogeneous Strength Parameters througnout the slooe ^ (°) C(psf) W.(pcf) Incl. H (ft) 38 200 130 2:1 35 2.2 Metavolcanic & Granitic Rock * Cut & Fill Slopes Average Shear Strength Values Where: .3' C W s H FS Angle of Internal Friction Cohesion (psf) Unit weight of Soil (pcf) Height of Slope (ft) Factor of Safety SOUTHERN CALIPORNIA ^^F^ SOIL A TESTINQ,INC. CALAVERA HEIGHTS - VILLAGE W-X-Y SOUTHERN CALIPORNIA ^^F^ SOIL A TESTINQ,INC. sv: KAR OATE: 5-03-90 SOUTHERN CALIPORNIA ^^F^ SOIL A TESTINQ,INC. JOB NUMBER: 9021054 Plate No. 15 RIPPABILITY NDEX NO RIPPING 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 VELOCITY, FT/SEC RESULTS S73-8 SOFT MEDIUM HARD BLASTING FTTl TRAVERSE NO. 573-9 / mj S73-1C S73-i;,573-1^ S73-i;'S73-l( / V I 'A a I & fl It? THE ABOVE RESULTS ATTEMPT TO SHOW DEPTHS TO HORIZONS OF VARYING DENSITY INDIFFERENT LOCATIONS OVER THE STUCV AREA. SEISMIC TRAVERSE NUMBERS^ REFER TO LOCATIONS PliOTED ON ATTACHED PLANS. THE*RIPRABIUTY INOEX'lS A MODIFICATION OF CHARTS BY THE CATERRLLAR CO. AND ARTICLE IN *ROADS AND STREETS; SEPT^ 1967. SOUTHERN CAUFORNIA TESTING r^C^ LABORATORY, INC. WUi^ 62S0 RIVEROALE STREET m^^JT SAN OlEQa CAUFORNIA 92120 714.2BM134 CALAVERA HEIGHTS-VILLAGE W-X-Y 1 SEISMIC RESULTS BY DBA OATE A-14-73 1 SEISMIC RESULTS JOB NO. 9021049 Plate No. 18 I WATERPROOF BACK OF WALL PER ARCHITECTS SPECIFICATIONS 3/4 INCH CRUSHED ROCK OR MARIDRAIN #000 OR EQUIVALENT GEOFABRIC BETWEEN ROCK ANO SOIL 4" DIAMETER PERFORATED PIPE •HOUSE ON QRADE SLAB HOUSE RETAINING WALL SUBDRAIN DETAIL NO SCALE SOUTHERN CALIPORNIA SOIL A TESTINQ,INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR DATE: 5-03-90 JOB NUMBER; 9021049 Plate No. 17 RIPPABiLiTY NDEX NO RIPPING SOFT MEDIUM HARD / kflT / BLASTING A A i ^ I I —i ' i—•• 1 ! T 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 / / / VELOCITY, FT/SEC. RESULTS TRAVERSE NO. 3PH nPKi.;,w^K.''n^L^S"'-^^ ATTEMPT TO SHOW DEPTHS TO HORIZONS OF VARYING DENSITY IN DIFFERENT LOCATIONS OVER THE STUCV AREA. SEISMIC TRAVERSE NUMBERS^ REFER TO LOCATIONS PIDTED ON ATTACHED PLANS THE RIPPABIUTY INDEX'IS A MODIFICATION OF CHARTS BY THE CATERPILLAR CO. AND ARTICLE IN 'ROADS AND STREETS; SEPT.^ 1967. CATERPILLAR SOUTHERN CALIFORNIA £OL-^ SOIL & TESTING LAB, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y • SEISMIC RESULTS BY DBA DATE 1-11-83 • SEISMIC RESULTS JOB NO. 9021049 Plate No. 19 1 I I I k I 3' WEAKENED PLANE JQNTS 10 THANSVERSE WEAKENED PLANE JOINTS 0- ON CENTER (MAXIMUM) SLABS IN EXCESS OF 10 FEET IN WIDTH w/2 W/2 ! ^"^^ i < \ 5'-'0' SLABS' 5 TO 10 FEET IN WIDTH PLAN NO SCALE n TOOLED JOINT r/2 — ' *- . (6'x6"-1 5 ^ 0/10) WELDED WIRE MESH WEAKENED PLANE JOINT DETAIL NO SCALE j^^K SOUTHERN CALIFORNIA Nnn^ SOIL 1 TESTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y j^^K SOUTHERN CALIFORNIA Nnn^ SOIL 1 TESTING, INC. BYi KAR OATEi.. 5-03-90 j^^K SOUTHERN CALIFORNIA Nnn^ SOIL 1 TESTING, INC. JOB NUMBERt 9021049 Plate No. 16 RIPPABILITY INDEX NO RIPPING SOFT MEDIUM HARD BLASTING 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 VELOCITY, FT/SEC. RESULTS TRAVERSE NO. GEDPH alb a jt? 9 lb fl I & fl it? CL UJ Q NOTE: THE ABOVE RESULTS ATTEMPT TO SHOW DEPTHS TO HORIZONS OF VARYING DENSITY IN DIFFERENT LOCATIONS OVER THE STUCY AREA. SEISMIC TRAVERSE NUMBERS ^ REFER TO LOCATIONS PiDTED ON ATTACHED PLANS. THE RIPPABIUTY INDEX'IS A MODIFICATION OF CHARTS BY THE CATERRLLAR CO. AND ARTICLE IN ROADS AND STREETS; SEPT^ 1967. SOUTHERN CALIFORNIA SOIL & TESTINC3 LAB, INC. SMO RIVBROAI.B BTRIKT BAN OIBOO, CAUIFORNIA BBIBO CALAVERA HEIGHTS-VILLAGE W-X-Y SEISMIC RESULTS •Y DBA JOB NO. 9021049 DATE 1-11-83 Plate No. 20 DSL CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 Seismic Velocity ^••t Par aaaoM i lOOO TOPSOIL CLAY IGNEOUS ROCKS SRANITE 3A8ALT SEDIMENTARY ROCKS 3HALE SANDSTONE SILTSTONE CLAYSTONE CONOLOMERATE METAMORPHIC ROCKS SCHIST SLATE i y / II 1/1/ ' • 1 i I 1 1 i / -I 1.^ RIPPABLE MAROINAL NON-RIPPABLE L DSL Ripper Performance • Multi or Single Shank No. 8 Ripper • Estimated by Seismic Wave Velocities SOUTHERN CALIFORNIA SOIL & TESTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021049 DATE: 5-03-90 Plate No. 21 ! 1 D9L CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 Seismic Velocity *••« ••oaw I 1000 TOPSOIL CLAY IGNEOUS ROCKS GRANITE 3ABALT SEDIMENTARY ROCKS 3HALE SANDSTONE SILTSTONE CLAYSTONE CONOLOMERATE METAMORPHIC ROCKS SCHIST SLATE RIPPABLE •0 n 12 13 14 15 D9L Ripper Performance • Multi or Single Shank No. 9 Ripper • Estimated by Seismic Wave Velocities SOUTHERN CALIFORNIA SOIL SL TESTING, INC. CALAVERA HEIGHTS-VILLARF W- BY: KAR jOB NUMBER: 9021049 X-Y DATE: 5-03-90 Plate No. 22 I I Dl IN CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 Seismic Velocity '••t Pw 'mmm m looo TOPSOIL CLAY IGNEOUS ROCKS QRANITE BASALT '/////] Dl 1 N Ripper Performance • Multi or Single Shank No. 9 Ripper • Estimated by Seismic Wave Velocities SOUTHERN CAUFORNIA SOIL 1 TESTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021049 DATE: 5-03-90 Plate No. 23 CALAVERA HEIGHTS VILLACaS W-X-Y, TAMARACK AND COLLEGE BCULEVARD, CARLSBAD REOOMMENEED (3»DING SPECIFICATIONS - (3WERAL PROVISICNS GQIERAL nUENT The intent of these specifications is to establish procedures for clearing, compacting natural ground, preparing areas to be filled, and placing and conpacting fill soils to the lines and grades shown on the accepted plans. The reconmendations contained in the preliminary geotechnical investigation report and/or the attached Special Provisions are a part of the Reconmended Grading Specifications and shall supersede the provisions contained hereinafter in the case of conflict. These specifications shall only be used in conjunction with the geotechnical report for which they are a part. No deviation from these specifications will be allowed, except where specified in the geotechnical report or in other written conmunication signed by the Geotechnical Engineer. 0BSERV7m:aN AIC TSSTISG Southern California Soil and Testing, Inc., shall be retained as the Geotechnical Engineer to observe and test the earthvrork in accordance with these specifications. It will be necessary that the Geotechnical Engineer or his representative provide adequate observation so that he may provide his opinion as to whether or not the vrork was acconplished as specified. It shall be the responsibility of the contractor to assist the Geotechnical Engineer and to keep him appraised of work schedules, changes and new infomation and data so thiat he may provide these opinions. In the event that any unusual conditions not covered by the special provisions or preliminary geotechnical report are encountered during the grading operations, the Geotechnical Engineer shall be contacted for further recommendations. (R-9/89) SCS&T 9021049 May 15, 1990 Appendix, Page 2 If, in the opinion of the Geotechnical Engineer, substandard conditions are encountered, such as questionable or unsuitable soil, unacceptable moisture content, inadequate conpaction, adverse v^eather, etc.; construction should be stopped until the conditions are remedied or corrected or he shall recommend rejection of this work. Tests used to determine the degree of conpaction should be performed in accordcince with the following Anerican Society for Testing and Materials test methods: Maximum Density & Optimum Jfoisture Content - ASTM D-1557-78. Density of Soil In-Place - ASTM D-1556-64 or ASTM D-2922. All densities shall be expressed in terms of Relative Compaction as determined by the foregoing ASTM testing procedures. PREPARATION OF AREAS TO RECEIVE FILL All vegetation, brush and debris derived from clearing operations shall be removed, and legally disposed of. All areas disturbed by site grading should be left in a neat and finished appearance, free from unsightly debris. After clearing or benching the natural ground, the areas to be filled shall be scarified to a depth of 6 inches, brought to the proper moisture content, conpacted and tested for the specified minimum degree of conpaction. All loose soils in excess of 6 inches thick should be removed to firm natural ground vdiich is defined as natural soils which possesses an in-situ density of at least 90% of its maximum dry density. (R-9/89) SCS&T 9021049 May 15, 1990 Appendix, Page 3 When the slope of the natural ground receiving fill exceeds 20% (5 horizontal units to 1 vertical unit), the original ground shall be stepped or benched. Benches shall be cut to a firm conpetent formational soils. The lower bench shall be at least 10 feet wide or 1-1/2 times the the equipment width vvMchever is greater and shall be sloped back into the hillside at a gradient of not less than tw (2) percent. All other benches should be at least 6 feet wide. The horizontal portion of each bench shall be conpacted prior to receiving fill as specified herein for conpacted natural ground. Ground slopes flatter than 20% shall be benched v^en considered necessary by the Geotechnical Engineer. Any abandoned buried structures encountered during grading operations must be totally renoved. All underground utilities to be abandoned beneath any proposed structure should be renoved from within 10 feet of the structure and properly capped off. The resulting depressions from the above described procedures should be backfilled with acceptable soil that is conpacted to the requirenents of the Geotechnical Engineer. This includes, but is not limited to, septic tanks, fuel tanks, sewer lines or leach lines, storm drains and water lines. Any buried structures or utilities not to be abandoned should be brought to the attention of the Geotechnical Engineer so that he may determine if any special recommendation will be necessary. All water wells which will be abandoned should be backfilled and capped in accordance to the requirements set forth by the Geotechnical Engineer. The top of the cap should be at least 4 feet below finish grade or 3 feet below the bottom of footing v^chever is greater. The type of cap will depend on the diameter of the well and should be determined by the Geotechnical Engineer and/or a qualified Structiaral Engineer. (R-9/89) SCS&T 9021049 May 15, 1990 Appendix, Page 4 FILL MATERIAL Materials to be placed in the fill shall be approved by the Geotechnical Engineer and shall be free of vegetable matter and other deleterious substances. Granular soil shall contain sufficient fine material to fill the voids. The definition and disposition of oversized rocks and expansive or detrinental soils are covered in the geotechnical report or Special Provisions. Ejq^ansive soils, soils of poor gradation, or soils with low stirength characteristics may be thoroughly mixed with other soils to provide satisfactory fill material, but only with the explicit consent of the Geotechnical Engineer. Any import material shall be approved by the Geotechnical Engineer before being brought to the site. PLACING AND CCMPACTION OF FILL Approved fill material shall be placed in areas prepared to receive fill in layers not to exceed 6 inches in conpacted thickness. Each layer shall have a uniform noist\rce content in the range that will allow the conpaction effort to be efficiently applied to achieve the specified degree of compaction. Each layer shall be uniformly compacted to the specified minimum degree of compaction with equipment of adequate size to economically compact the layer. Conpaction equipment should either be specifically designed for soil conpaction or of proven reliability. The niinimum degree of conpaction to be achieved is specified in either the Special Provisions or the recommendations contained in the preliminary geotechnical investigation report. When the structural fill material includes rocks, no rocks will be allovi to nest and all voids must be carefully filled with soil such that the minimum degree of conpaction recommended in the Special Provisions is achieved. The maximum size and spacing of rock permitted in structural fills and in non-structural fills is discussed in the geotechnical report, when applicable. (R-9/89) SCS&T 9021049 May 15, 1990 Appendix, Page 5 Field observation and conpaction tests to estimate the degree of conpaction of the fill will be taken by the Geotechnical Engineer or his representative. The location and frequency of the tests shall be at the Geotechnical Engineer's discretion. When the conpaction test indicates that a particular layer is at less than the required degree of conpaction, the layer shall be reworked to the satisfaction of the Geotechnical Engineer and until the desired relative conpaction has been obtained. Fill slopes shall be conpacted by neans of sheepsfoot rollers or other suitable equipnent. Compaction by sheepsfoot rollers shall be at vertical intervals of not greater than four feet. In addition, fill slopes at a ratio of two horizontal to one vertical or flatter, should be trackrolled. Steeper fill slopes shall be over-built and cut-back to finish contours after the slope has been constructed. Slope conpaction operations shall result in all fill material six or nore inches inward from the finished face of the slope having a relative conpaction of at least 90% of maximum dry density or the degree of conpaction specified in the Special Provisions section of this specification. The conpaction operation on the slopes shall be continued imtil the Geotechnical Engineer is of the opinion that the slopes will be stable surficially stable. Density tests in the slopes will be made by the Geotechnical Engineer during construction of the slopes to determine if the required conpaction is being achieved. Where failing tests occur or other field problems arise, the Contractor will be notified that day of such conditions by written conmunication from the Geotechnical Engineer or his representative in the form of a daily field report. If the nethod of achieving the required slope conpaction selected by the Contractor fails to produce the necessary results, the Contractor shall rework or rebuild such slopes until the required degree of conpaction is obtained, at no cost to the Owner or Geotechnical Engineer. (R-9/89) SCS&T 9021049 May 15, 1990 Appendix, Page 6 COT SLOPES The Engineering Geologist shall inspect cut slopes excavated in rock or lithified formational material during the grading operations at intervals determined at his discretion. If any conditions not anticipated in the preliminary report such as perched water, seepage, lenticular or confined strata of a potentially adverse nature, unfavorably inclined bedding, joints or fault planes are encountered during grading, these conditions shall be analyzed by the Engineering Geologist and Soil Engineer to determine if mitigating measures are necessary. Unless otherwise specified in the geotechnical report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of the controlling govemmental agency. ENGINEERING OBSERVATICN Field observation by the Geotechnical Engineer or his representative shall be made during the filling and conpacting operations so that he can express his opinion regarding the conformance of the grading with acceptable standards of practice. Neither the presence of the Geotechnical Engineer or his representative or the observation and testing shall not release the Grading Contractor from his duty to compact all fill material to the specified degree of compaction. SEASCN LIMnS Fill shall not be placed during unfavorable weather conditions. When work is interrupted by heavy rain, filling operations shall not be resumed until the proper moisture content and density of the fill materials can be achieved. Damaged site conditions resulting from weather or acts of God shall be repaired before acceptance of vork. (R-9/89) SCS&T 9021049 May 15, 1990 Appendix, Page 7 RBOQMMENraD GRADING SPECIFICATIONS - SPBCI7VL PROVISIONS FEUSnVE CCMPACTION: The minimum degree of conpaction to be obtained in conpacted natural ground, conpacted fill, and conpacted backfill shall be at least 90 percent. For street and parking lot si±)grade, the upper six inches should be conpacted to at least 95% relative conpaction. EXPANSIVE SOILS: Detrimentally expansive soil is defined as clayey soil v^iich has an expansion index of 50 or greater when tested in accordance with the Uniform Building Code Standard 29-C. OVERSIZED MKEEEIEAL: Oversized fill material is generally defined herein as rocks or lunps of soil over 6 inches in diameter. Oversize materials should not be placed in fill unless reconmendations of placement of such material is provided by the geotechnical engineer. At least 40 percent of the fill soils shall pass through a No. 4 U.S. Standard Sieve. TRANSmCN LOIS: Where transitions between cut and fill occur within the proposed building pad, the cut portion should be undercut a minimum of one foot below the base of the proposed footings and reconpacted as structural backfill. In certain cases that would be addressed in the geotechnical report, special footing reinforcement or a confcination of special footing reinforcement and undercutting may be required. (R-9/89)