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HomeMy WebLinkAboutCT 01-05; CALAVERA HILLS VILLAGE W; INTERIM RPT OF GEOTECH INV VILLAGE W-X-Y;INIERIM REPCKO' OF CTGOBCHNICAL INVESTIGBTICN CALfiVETtA HEIGHTS VXLLAOS W-X-Y TAMARACK AND CX3LLB^ BCXILEVARD CARLSBAD, CALIPCWNIA PREPARED FOR: Lyon Gonnunitu.es r Incorporated 4330 La Jolla Village Drive, Suite 130 San Diego, Califomia 92122 PREPARED BY: Southern Califomia Soil & Testing, Inc. Post Office Box 20627 6280 Riverdale Street San Diego, Califomia 92120 CT0/'06 SOUTHERN CALIFORNIA SOIL AND TESTING, INC. 62B0 RIVERDALE ST. SAN D.EGO, CALir. 9212D • TELE 2SD.43Z. • P.O. BOX 20627 SAN DIEGQ. CALIF. 92,20 e , B ENTERPRISE ST. E S C O N D . D O. C A L . r. , Z O Z S • TELE , - 6 - - 5 - - May 15, 1990 Lyon Canminities, Incorporated 4330 La Jolla Village Drive Suite 130 San Diego, Califomia 92122 SCS&T 9021049 Report Nb. 1 ATTENTION: Mr. George Haviar SUBJECT: Interim Report of Geotechnical Investigation, Calavera Heights Villages W-X-Y, Tamarack and College Boulevard, Carlsbad, Califomia. Gentlemen: In accordance with your request, we liave conpleted an interim geotechnical investigation for the subject project. Vfe are presenting herewith our findings eind recottmendations. In general, we found the site suitable for the proposed developnent provided the recomnnendations 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, SOOTHEWJ CAI/IFDRNIA^SOii/ & 'A 'ING, INC. Daniel B. Atiler, R.C.E. #36037 DBA:JRH:KAR:mw cc: (2) Submitted (4) Hunsaker and Associates (1) SCS&T, Escondido SOUTHERN CALIFDRNIA tohn R. High, C.E.G AND TESTING TABLE OF COMHWrS PPCE Introduction and Project Description 1 Project Scope Findings Site Description General Geology and Subsurface Conditions Geologic Setting and Soil Description 3 1) Basement Conplex-Jurassic Metavolcanics and Cretaceous Granitics (Jmv^/Kgr) 4 2) Santiago Formation {Es) 5 3) Older Quatemary (Pleistocene) Alluvium (Qoal) 5 4) Younger Quatemary (Holocene) Alluvium (Qyal) 5 Tectonic Setting "l Geologic Hazards ^ Groundshaking ° Seismic Survey and Rippability Characteristics 8 General • ^ Rippability Characteristic of Granodioritic Rock 12 Rippable Condition (0-4,500 Ft./Sec.) 12 Marginally Rippeible Condition (4,500 Ft./Sec.-5,500 Ft./Sec) 13 Nonrippable Condition (5,500 Ft./Sec. & Greater) 13 Rifpability 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 Conclusions and Reconmendations 1° General ^° Grading Site Preparation 1' Select Grading 1^ Cut/Fill Transition 1^ Inported Fill 1^ Rippability 18 Oversized Rock ^° Slope Construction 18 Surface Drainage 18 Subdrains 1^ Earthwork 1^ Slope Stability 19 Foundations 1^ General 1^ Reinforcement 20 Interior Concrete Slabs-on-Grade 20 Exterior Concrete Slabs-on-Grade 21 Special Lots 21 Expansive Characteristics 21 Settlenent Characteristics 21 Earth Retaining Walls 22 Peissive Pressure 22 Active Pressure. ,22 TABLE OF COMTENIS (continued) PAGE Backfill ll Factor of Safety Limitations _ , Review, Obseivation and Testing ^-i Uniformity of Conditions Change in Scope Time Limitations Professional Standard Client's Responsibility Field Explorations Laboratory Testing MTACHMENTS TABLES Table I Table II Table III Generalized Engineering Characteristics of Geologic Units, Page 6 The Maximum Bedrock Accelerations, Page 8 Seismic Traverse Sunmary, Pages 9 through 12 FIGURE Figure 1 Site Vicinity Map, Follows Page 1 FLAXES Plate 1 Plot Plan Plate 2 Unified Soil Classification Chart Plates 3-9 Trench Logs Plate 10 Grain Size Distribution Plate 11 Conpaction Test Results Expansion Test Results Plate 12 Direct Shear Summary Plate 13 Oversize Rock Disposal Plate 14 Canyon Subdrain Detail Plate 15 Slope Stability Calculations Plate 16 Vfeakened Plane Joint Detail Plate 17 Retaining Wall Subdrain Detail Plates 18-20 Seismic Line Traverses Plates 21-23 Catepillar Rippability Charts Reconmended Grading Specification and Special Provisions SOUTHERN CALIFORNIA SOIL AND TESTING, INC. S2S0 mVERDALE ST. SAN DIEGO. CALir. 92,20 • TELE2B0..32, • P.O. BOX 20627 SAN DIEGO CAL.r. 92,,a ENTERPRISE ST. ESCONO.OO, C . . . T. ,,C.S • TE.E , miERIM REPORT OF GBOIBCHNICAL INVESTIGATICN CALAVERA HEICSnS VILLAGES W-X-Y TAMARACK AND COLLEGE BOULEVARD CARLSBAD, CALIFORNIA INTRODOCnON AND PROJECT DESCRIPTICN 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 Nunter 1. It is our understanding that the site will be developed to receive a residential subdivision with associated paved streets. It is anticipated that the structures will be one and/or tvro stories high and of vrood frame construction. Shallow 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. Ito assist with the preparation of this report, ^ vere provided with a grading plan prepared by Hunsaker and Associates dated Decenber 6, 1989. In addition we reviewed our "Supplenental 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 CALIFORNIA SOIL AND TESTING, INC. •OUTHBRM CALIPORNIA SOIL A TBSTINQ,INC. CALAVERAS HEIGHTS-VILLAGE •OUTHBRM CALIPORNIA SOIL A TBSTINQ,INC. BV: KAR/EM DATI: 5-15-90 •OUTHBRM CALIPORNIA SOIL A TBSTINQ,INC. FIGURE #1 SCS&T 9021049 May 15, 1990 ^^9® 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 when 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 nentioned 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 perfomed in the referenced report was used to evaluate the pertinent engineering properties, including bearing capacities, expansive characteristics and settlement potential, of the anticipated materials which will influence the developnent of the proposed subject site. c) Describe the rippability characteristics of the existing rock. d) Define the general geology at the site including possible geologic hazards vAvLch could have an effect on the site developnent. e) Develop soil engineering criteria for site grading and provide recomtendations regarding the stability of proposed cut and fill slopes. f) Address potential constmction difficulties and provide reconmendations conceming these problems. SCS&T 9021049 May 15, 1990 Pag® 3 g) Reconmsnd an appropriate foundation system for the type of structures anticipated and develop soil engineering design criteria for the reconmended foundation design. FINDINGS STTE EESCRIPnCW 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 west. Topographically, the site is located in hilly terrain with veil developed, large, drainage courses with steep-sided slopes. Elevations range from approxijnately 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 the 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 pover lines. GE2IERAL GEOUJSI AND SUBSURFACE OCNDITICNS CTCEOnC SETTIMG AM) SOIL raSCRIPTICN: The subject site is located near the boundary between the Foothills Physiographic Province and the Coastal Plains Pl^iographic Province of San Diego County and is underlain by materials of igneous and sedimentary origin and surficial residuum. "The site is underlain by the basenent conplex rocks consisting of Jurassic-age netavolcanic rocks. Cretaceous-age granitic rocks, as well as Tertiary-age Santiago Formation and Quatemary-age alluvium. A brief description of the materials on-site, in general decreasing order of age, is presented below. SCS&T 9021049 May 15, 1990 ^ 1) BASEMEOT CCMPLEX - JURASSIC METAVOLCANICS AND CRETTBCBOUS GRANITICS (Jimr/Kgr): 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 netavolcanics and are consequently older than the other intmsive rocks found at the site. Both the metavolcanics and the associated hypabyssal rtxrks 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-moving equipnent 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 intmded the older rocks and are, to a large degree, mixed with them. The granitic rocks at the project site appear to be both tonalitic and granodioritic in conposition. The tonalitic rocks are usually dark gray, fine to nedium grained rocks whereas 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 netavolcanic rocks but ripping may be difficult and tine consuming. 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 conrnonly contain areas which are rippable to SCS&T 9021049 Mav 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 basenent 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 basenent rock types are very irregular, therefore they were not differentiated on Plate Number 1. 2) SANTIAGO FC»RMATION (Es): The Eocene sediments 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 most of the Santiago Formation. 3) OLDER QU2flERNARy (PI£ISrOCENE) 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) YDCNC3ER CJUATERNARY (HC3L0CENE) ALLUVIUM (Qyal): Younger alluvial deposits consisting of unconsolidated, loose to medium dense deposits 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 subsoils 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 combined thickness. Table I presents sone of the pertinent engineering characteristics of the materials at the site. •TABLE I (3NERALIZED ENGINEERING CHARACTERISTICS OF MAIN GEOUXilC UNITS Unit Name and Symbol Rippability Amount of Oversize Material Slope Stability/ Erosion Conpress ibility Ej^sansive Potential Granitic Rocks- Kgr (Granodiorite) Granitic Rocks- Kgr (Tonalite) Metavolcanic and Hypabyssal Rocks-Jmv Santiago Formation-Es (Mudstone) Santiago Formation-Es (Sandstone and Siltstone) Older Alluvium-Qoal Generally Rippable to + 15 Feet Marginally Rijpable to Nonrippable Marginally Rippable to Nonrippable Rippable Rippable Rippable Low to Moderate Moderate to High Moderate to High Nominal Nominal Nominal Good Nominal Good Nominal Good Nominal Generally Poor Generally Good Low Low Moderately Erodible Moderate to High Nominal Nominal Nominal Moderate to High Low to Moderate Low to High SCS&T 9021049 May 15, 1990 Page 7 TBCICNIC 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 some 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 stmctural trend) and in a general northeasterly direction (subperpendicular to the regional stmctural 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 northwest trending faults that could possibly be classified as 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 Clenente Fault Zones to the vest, the Agua Bianca and San Miguel Fault Zones to the south, and the Elsinore and San Jacinto Fault Zones to the noi±heast. GBQLCXnC HAZARDS: The site is located in an area vrfiich is relatively free of potential geologic hazards. Hazards such as tsvinamis, seiches, liquefaction, and landsliding should be considered negligible or nonexistent. SCS&T 9021049 May 15, 1990 Page 8 GTOUNDSHAEONG: One of the most 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 vrould be attributed to a maximum probable earthquake occurring along the nearest portion of selected fault zones that could affect the site are summarized in the following Table II. -TABLE II Maximum Probable Bedrock Design r aux u ctLji vs Rose Canyon 8 miles 6.5 nagnitude 0. 36 g 0. 23 g Elsinore 20 miles 7.3 magnitude 0. 25 g 0. 17 g Coronado Banks 24 miles 7.0 magnitude 0. 18 g 0. 12 g San Jacinto 43 miles 7.8 magnitude 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 BanJcs, San Jacinto, or Elsinore Fault Zones. Ej^rience has shown that stmctures that are constmcted in accordance with the Uniform Building Code are fairly resistant to seismic related hazards. It is, therefore, our opinion that stmctural 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. SEiaaC SURVEY AND RIPPABnJTY CHARACIERISTICS GENERAL: The results of our seismic survey and exploratory trenches perfomed 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 sunnary of each seismic traverse is presented in Table III SCS&T 9021049 May 15, 1990 Page 9 below, and Plates Number 18 through 20. Our interpretation is based on the rippability characteristics of granitic and netavolcanic rock as described in Pages 12 through 15. •TABLE III Seismic Ttawerse No. S73-14 Proposed Cut: 48 Feet Geologic Unit: Metavolcanic Interpretation: 0'-15' Nonrippable Seismic Traverse No. SW-10 Proposed Cut: 50 Feet Geologic Unit: Metavolcanic Interpretation: 0'- 3' Rippable 3'-17' Rippable with Hardrock Floaters 17'-30' Nonrippable Seismic Traverse No. SW-IOR Proposed Cut: 50 Feet Geologic Unit: Metavolcanic Interpretation: 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'-2 7' Nonrippable Seismic Traverse Ho. SW-llR Proposed Cut: None Geologic Unit: Metavolcanic Interpretation: 0'- 6' Rifpable 6'-2 7' Nonrippable SCS&T 9021049 May 15, 1990 Page 10 TABLE III (continued) Seismic Traverse No. SW-12 Proposed Cut: 29 Feet Geologic Unit: Metavolcanic Interpretation: 0'- 6' Rippable 6'-21' Marginally Rippable with Hardrock Floaters + 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: 13 Feet Geologic Unit: Metavolcanic Interpretation: 0'- 4' Rippable 4'-15' Rippable with Hardrock Floaters + 15' Nonrippable Seismic Traverse No. SW-14 Proposed Cut: 38 Feet Geologic Unit: Metavolcanic Interpretation: 0'- 4' Rippable 4'-21' Rippable with Hardrock Floaters + 21' Nonrippable Seismic Traverse No. SW-14R Proposed Cut: 38 Feet Geologic Unit: Metavolcanic Interpretation; 0'- 3' Rippable 3'-14' Rippable with Hardrock Floaters 14'-30' Marginally Rippable with Hardrock Floaters SCS&T 9021049 May 15, 1990 Page 11 TABL£ III (continued) Seismic Traverse No. SX-15 Proposed Cut: Geologic Unit: Interpretation: Unknown Metavolcanic 0'- 6' Rippable 6'-15' Rippable with Hardrock Floaters + 15' Nonrippable Seismic Traverse No. SX-15R Proposed Cut: Unknown Geologic Unit: Metavolcanic Interpretation: O'-ll' Rippable + 11' Nonrippable Seismic Traverse No. SZl-16 Proposed Cut: Geologic Unit: Interpretation: None Granitic 0'-16' 16'-27' + 27' Rippable Rippable with Hardrock Floaters Nonrippable Seismic Traverse No. SZ1-16R Proposed Cut: None Geologic Unit: Metavolcanic/Granitic Interpretation: 0'-20' Rippable with Hardrock Floaters + 20' Nonrippable Seismic Traverse No. SZ2-17 Proposed Cut: UnJarawn Geologic Unit: Mstavolcanic/Granitic Interpretation: 0'- 5' Rippable + 5' Nonrippable SCS&T 9021049 May 15, 1990 Page 12 TABL£ III (continued) Seismic Traverse No. SZ2-17R Proposed Cut: UnJoiown Geologic Unit: Metavolcanic/Granitic Interpretation: 0'-20' Rippable with Hardrock Floaters + 20' Nonrippable In general, our seismic survey indicated that areas underlain by granitic rock present rippable material to depths ranging up to approximately 27 feet, with nonrippable naterial below this depth. In areas underlain by netavolcanic and associated hypabyssal rock, nonrippable materials appear to be encountered at depths of approximately 0 feet to 21 feet. In addition, a variable zone of marginally rippable rock usually exists between the rippable and nonrippable rock. The generation of fine material during blasting and mining operations is essential due to the characteristics of the on-site rock material. Therefore, "pre-shooting" of nonrippable material before removing the overlying soils and rippable rock is suggested. This procedure often helps to generate nore fine naterial and to facilitate the mixing of soil and rock to be used as fill. RIPPABILrry CHARACTERISTIC OF (3W«CDI0RITIC ROCK RIPPABLB CCMDinCN (0-4,500 FT./SBC.): This velocity range indicates rippable materials which may consist of deconposed granitic rock possessing random hardrock floaters. These materials will break down into slightly silty, well graded sand, v*iereas the floaters will require disposal in an area of nonstmctural fill. Some areas containing nunerous hardrock floaters nay present utility trench problems. Further, large floaters ejqjosed at or near finish grade may present additional problems of removal and disposal. SCS&T 9021049 May 15, 1990 Pag® 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 RIPPAHLJE CONDITION (4,500 rT./SEC.-5,500 FT./SBC.): 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" naterial. Less fractured or v^athered 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. NONRIPPAHL£ CCTOmCN (5,500 FT./SBC. & 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 naterial requiring disposal in areas of nonstmctural fill. This upper limit has been based on the Rippability Chart shown on Plates Nuntaer 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 nay sonetines be increased to 7,000 to 8,000 fps material using the D-9 mounted #9 Series D Ripper. PTPPARTT.rry CHARACIERISTICS OF MErDWQLCANICS AND ASSGCIAaH) HYPABYSSAL ROCKS AND TONALITIC ROCKS RIPPABB^ CCMDITION (0-4,500 FT./SBC.): This velocity range indicates rippable naterials vdiich nay vary from deconposed 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. Experience 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" naterial. For velocities between 3,500 to 4,500 fps, rippability will be difficult for backhoes and light trenching equipment. MAKSINALLY RIPPABLE OONDITION (4,500-5,500 FT./SBC.): Excavations in this velocity range vrould be extrenely time consuming and vrould produce fractured rock with little or no fines. The higher velocities could require blasting. Trenching equipnent would not function. NONRIPPABLE OONDITION (5,500 FT./SBC. & GREATER): This velocity range nay include noderately to slightly fractured rock which vrould require blasting for removal. Material produced would consist of a high percentage of oveisize and cingular rock. Rippability of netavolcanics may be acconplished for higher velocities using the Caterpillar D-9 with the #9 D Series Ripper. Due to the fractured nature of sone netavolcanics, ripping might be accomplished in as high as 8,000 fps material. SEISMIC TRAVERSE LIMITKTICNS 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 nay be assuned 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 method requires that materials become increasingly dense with depth. In areas where denser, higher velocity materials are underlain by lower velocity materials, the lower 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 Deconposition 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 rijping of higher velocity materials may become totally dependent on the tine available and the econonics of the project. Ripping of higher velocity naterials can be achieved but it nay becone economically infeasible. OtOUNDWATER: No groundwater was encountered during our subsurface explorations for the referenced reports. Even though no najor groundwater problems are anticipated either during or after constmction of the proposed development, seasonal groundwater from precipitation mnoff may be encountered within the larger drainage swales during grading for the developnent. It is suggested that carbon subdrains be installed within drainage swales which are to receive fill. It should be realized that groundwater problems may occur after developnent of a site even v^iere none were present before developnent. These are usually minor phenomena and are often the result of an alteration of the pemeability 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 developnent, 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 when they develop. CONCLUSICNS AND RBCXMENDATICNS GEUEIRAL In general, no geotechnical conditions were encountered which vrould preclude the development of the site as tentatively planned, provided the reconnendations presented herein are followed. The main geotechnical condition that will affect the proposed site development include hard granitic, netavolcanic, and hypabyssal rock, which 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 anounts of fine soils and large amounts of oversized material. Since rock fills require a percentage of fine soil, mining of the site, inporting of fine naterials or exporting excess rock may be necessary. Existing loose surficial deposits such as topsoils, subsoils, younger alluvium, and any weathered formational materials encountered are considered unsuitable for the support of settlenent sensitive inprovenents, and will require reraoval and/or replacenent as conpacted fill. Expansive soils vere also present within the subject area. Where possible, select grading is reconnended to keep nondetrinentally expansive soils within four feet from finish pad grade. In areas where this is not feasible, special foundation consideration will be necessary. Hbwever, it is anticipated that only minor amounts of e^qjansive soils vtfill be encountered. SCS&T 9021049 OUTING Mav 15, 1990 Page 17 SITE PREPARKTICN: Site preparation should begin with the removal of any existing vegetation and deleterious matter from proposed improvement 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 reconpacted to at least 90 percent as determined in accordance with ASIM D 1557-78, Method A or C. The minimum horizontal limits of removal should include at least five feet beyond the perimeter of the stmctures, and all areas to receive fill and/or settlement-sensitive inprovenents. SELECT GRMSnCi Expansive soils should not be allowed vd.thin 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 more. Select material should consist of granular soil with an expansion index of less than 50. It is reconnended that select soils have relatively low pemeability 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. Minimum lateral extent of select grading should be five feet away from the perimeter of settlement-sensitive inprovenents. COT/FILL TRAiemCK: 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 settlenent characteristics of cut and fill soils, constmction of a stmcture partially on cut and partially on fill is not reconmended. Based on this, we reconnend 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 minimum horizontal limits of these reconnendations should extend at least five feet outside of the propxosed inprovenents. IMPORIED FHi: All fill soil imported 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 imported should be approved by a representative of this office prior to inporting. RIPPABILrnr: It is anticipated that the proposed cuts will require heavy ripping and blasting. Plates Number 18 through 20 contain the results of our seismic traverses. The results are sunmarized 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 vrtiere deep cuts are proposed. 0VEI6IZED HOCK: Oversized rock is defined as material exceeding six inches in maxirtum dinension. It is anticipated that oversized naterial will be generated from proposed cuts. Oversized naterial may be placed in stmctural fills as described in Plate Number 13. SLOPE CONSTROCnCN: The face of all fill slopes should be conpacted by backrolling with a sheepjsfoot conpactor at vertical intervals no greater than four feet and should be track walked when conpleted. Select grading should be perfomed 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 DRIUNAGE: It is reconnended that all surface drainage be directed away from the stmctures 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. EARfflWORK: All earthwork and grading contemplated for site preparation should be acconplished in accordance with the attached Reconnended Grading Specifications and Special Provisions. All special site preparation reconnendations presented in the sections above will supersede those in the Standard Reconnended Grading Specifications. All embankments, stmctural fill and fill should be conpacted to at least 90% relative conpaction at or slightly over optimum moisture content. Utility trench backfill within five feet of the proposed stmctures and beneath asphalt pavenents should be corapacted to mimmum of 90% of its maximum dry density. The upper tvelve inches of subgrade beneath paved areas should be conpacted 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 nass 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 STZVBILITy 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 naximum 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 Nuniber 15). The engineering geologist should observe all cut slopes during grading to ascertain that no adverse conditions are encountered. F0UM3ATI0NS GH^ERAL: If the lots are capped with nondetrinentally expansive soils, conventional shallow foundations may be utilized for the support of the proposed stmctures. The footings should have a mininum depth of 12 inches SCS&T 9021049 May 15, 1990 Page 20 and 18 inches below lowest adjacent finish pad grade for one-and-tvro-story constmction, respectively. A minjjnum width of 12 inches and 18 inches is reconnended 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 when 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 nondetrinentally 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. Reconnendations for expansive soil conditions will be provided after site grading when the expansion index and depth of the prevailing foundation soils are laiown. REINPOIOMEKr: 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 Nb. 4 bar positioned near the top of the footing. This reinforcenent is based on soil characteristics and is not intended to be in lieu of reinforcement necessary to satisfy stmctural considerations. If expansive soils exist within four feet of finish grade, additional reinforcing vrill be necesseuy- 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 reinforcement should be placed near the middle of the slab. As an altemative, the slab reinforcing nay consist of 6"x6"-W1.4xW1.4 (6"x6"-10/10) velded wire mesh. Hcwever, it should be realized that it is difficult to naintain the proper position of wire nesh during placement of the concrete. A four-inch-thick layer of clean, coarse sand or cmshed 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. EXTERIOR SUVBS-CN-GRADE: 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) voided wire nesh 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 reconnendations 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. EKPANSIVE CHARflClERISnCS: 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. SETTUOIDIT ODWACEBRISnCS: The anticipated total and/or differential settlements for the proposed stmctures may be considered to be within SCS&T 9021049 May 15, 1990 Page 22 tolerable limits provided the reconnendations 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. EARTH 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 naximum of 2000 psf. This pressure may be increased one-third for seismic loading. The coefficient of friction for concrete to soil may be assuned to loe 0.35 for the resistance to lateral movenent. When combining frictional and passive resistance, the fomer should be reduced by one-third. The upper 12 inches of exterior retaining wall footings should not be included in passive pressure calculations v^en 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 veighing 35 pounds per cubic 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. BACKFILL: All backfill soils should be conpacted to at least 90% relative conpaction. E3q>ansive or clayey soils should not be used for backfill material. The wall should not be loackfilled until the masonry has reached an adequate strength. EftCTOR OF SAFEW: The above values, with the exception of the allowable soil bearing pressure, do not include a factor of safety. ji^ropriate 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 LIMITATICNS REVIEW, OBSERVZm:CN AND TESTING The reconnendations 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 reconmended 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 reconnendations and to allow design changes in the event that subsurface conditions differ from those anticipated prior to start of constmction. imPDRMrrr OF CCNDITICKS The reconnendations 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 assumption 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 intemediate and unexplored areas. Any unusual conditions not covered in this report that may be encountered during site development should be brought to the attention of the geotechnical engineer so that he may make modifications if necessary. CHNNGE IN SaOPE 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 modified by a voritten addendum. SCS&T 9021049 TIME LIMITATICNS May 15, 1990 Page 24 The findings of this report are valid as of this date. Changes in the condition of a property can, hovrever, occur with the passage of time, whether they be due to natural processes or the work 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 nay 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 recommendations. PROFESSIONAL STANDARD In the perfomance of our professional services, we conply with that level of care and skill ordinarily exercised by members of our profession currently practicing under similar conditions and in the sane locality. The client recognizes that subsurface conditions may vary from those encountered at the locations v^iere our trenches, surveys, and explorations are made, and that our data, interpretations, and recOTnendations are based solely on the information obtained by us. We will be responsible for those data, interpretations, and reconnendations, 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 vrork perfomed or to be perfomed by us, or by our proposal for consulting or other services, or by our fumishing of oral or written reports or findings. CLIEWr'S RESPCNSIBIUTY It is the responsibility of Lyon Commimities Incorporated, or their representatives to ensure that the information and reconnendations 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 measures to insure that the contractor and his subcontractors carry out such reconmendations during constmction. FIELD EXPLCWKTIONS Three subsurface trench explorations vere nade at the locations indicated on the attached Plate Nunfcer 1 on December 21, 1982, and three on July 7, 1983, adjacent to or within the subject site (see Plates Nunfcer 3 through 6). In addition. Plates Nunfcer 7 through 9 from the referenced reports contain additional trench excavations nade in December 15, 1982, of similar soils within the subject subdivision. These explorations consisted of trenches dug by the means of a backhoe. One seismic traverse was performed on i^ril 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 Nunfcer 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, nedium stiff, stiff, very stiff, or hard. LADCKMORY TESTING Laboratory tests were perfomed in accordance with the generally accepted Anerican Society for Testing and Materials (ASTM) test nethods or suggested procedures. A brief description of the tests perfomed is presented below: a) CLfiSSIFICKnCN: 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) M)ISTURE-DENSITY: In-place moisture contents and dry densities were determined for representative soil samples. 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 sunmarized in the trench logs. c) GRMN SIZE DISTRIBOTION: 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 Number 10. d) OCMPACnON TEST: The maximum dry density and optimum moisture content of typical soils were 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 Nunfcer 11. Allow the trimned, 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 conpress under a load of 150 psf. Allow noisture to contact the sanple and neasure its expansion from an air dried to saturated condition. f) DIRBCT SHEAR TESTS: Direct shear tests were perforned to detemiine the failure envelope based on yield shear strength. The shear box vras designed to accommodate a sanple having a SUBSURFACE EXPLORATION LEGEND UNIFIED SOIL CLASSIFICATION CHART SOIL DESCRIPTION COARSE GRAINED, more than half of material is larger than No. 200 sieve size. GRAVELS CLEAN GRAVELS More tnan half of coarse fraction is larger than No. 4 sieve size but GROUP SYMBOL GW smaller than 3" GRAVELS WITH FINES (Appreciable amount of fines) SANDS CLEAN SANDS More than half of coarse fraction is smaller than No. 4 sieve size. SANDS WITH FINES (Appreciable amount of fines) II. FINE GRAINED, more than half of material is smaller than No. 200 sieve size. SILTS ANO CLAYS Liquid Limit less than 50 SILTS ANO CLAYS Liquid Limit greater than 50 GP GM GC SW SP SM SC ML CL OL MH CH OH HIGHLY ORGANIC SOILS PT fYPK NAMES Well graded gravels, gravel- sand mixtures, little or no fi nes. Poorly graaed gravels, gravel sand mixtures, little or no fines. Silty gravels, poorly graded gravel-sand-silt mixtures. Clayey gravels, poorly graded gravel-sand, clay mixtures. Well graded sand, gravelly sands, little or no fines. Poorly graded sands, gravelly sands, little or no fines. Silty sands, poorly graded sand and silty mixtures. Clayey sands, poorly graded sand and clay mixtures. Inorganic silts and very fine sands, rock flour, sandy silt or clayey-silt-sand mixtures with slight plas- ticity. Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays. Organic silts and organic silty clays or low plasticity, Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts. Inorganic clays of high plasticity, fat clays. Organic clays of medium to high plasticity. Peat and other highly organic soils. US Water level at time of excavation or as indicated Undisturbed, driven ring sample or tube sample CK — Undisturbed chunk sample BG — Bulk sample SP — Standard penetration sample y/V SOUTHERN CALIFORNIA SOIL A TBSTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y y/V SOUTHERN CALIFORNIA SOIL A TBSTING, INC. BY: KAR/EM DATE: 5-03-90 y/V SOUTHERN CALIFORNIA SOIL A TBSTING, INC. JOB NUMBER: 9021049 Plate No. 2 I Class TRENCH ::o. Description •50 SM Gray-brovrn, Moist, Dense co Very Dense, Siltv Sand (Decomposed Granice) Trench Ended at 4 Feet y\ SOUTHERN CALIFORNIA XSCjS soil- & TEBTINQ, INC. ^yl^^ SAN OIMO, CALiranNIA ••^BO CALAVERA HEIGHTS-VILLAGE W-X-Y BY CRB DATE 12-21-82 JOB NO. 9021049 Plate Mo. 3 -'ISM/ sc / ^JTOOT Red-brov.Ti, ISC. ..eaium Jense. •?3Cii } Veilow-bro;m, ..ea-brown, Jrav-brcim. M.oist, llediurn Dense. Clavev Silcv Sand. Porous (Older .liiuvium') Sandv Clav/Clavev Sand Trench ^ndeQ ac iO Feet 113.: 8.0 i(y/.8 15.5 fl SOUTHERN CALIFORNIA \ SOIL & TESTIIMQ, INC. •AN Oirao, CALiranNIA ••^•a CALAVERA HEIGHTS--VILLAGE W-X-Y 1 BY CRB DATE 12-21-82 1 JOB NO. 9021049 Plate I'o. 4 .ass e s c r: SI'/ F.ec-brown. .''cisc. I'.ediurr. D<,inse, clayey S ilrv S.-ind (""•..•osoii) li SM Vej.iow ana urav-orouTv. ..Jisc, Dense co Ver\ Dense. SilCv Sand (Cecioir.Dosed Granite) Trench Ended ac i Feet 5i> SOUTHERN CALIFORNIA SOIL & TESTINQ , INC. •AN aiano, CAi.if>aNNiA ••^•a CALAVERA HEIGHTS--VILLAGE W-X-Y • CRB DATE 12-21-82 i JOB NO. 9021049 Plate No. 5 z Ol o Q. t-TY CA L E 5 u. a. Cfl cn < < cn TRENCH NUMBER TX-77 ELEVATION t- UJ Z tc < W a. — Q. O < z Z UJ c CL a. < •ESCRIPTION > O z UJ <A Z (A UJ « ° Z o o > I- o z _ UJ — ° 1 >-cc Q UJ ?5 tr I ^ 5 ^ 5 O o z o a Z o o GM BROWN SANDY GRAVEL (TOPSOIL) | HUMID/ MEDIUM MOIST I DENSE 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' SOUTHERN CALIFORNIA SOiL &TESTiNG,INC. SUBSURFACE EXPLORATION LOG LOGGED BY: CRB JOB NUMBER: 9021049 DATE LOGGED: 7-18-83 Plate No. 6 TRENCH NUMBER :_ = VAT;C: N DEEOP.IPTICN ac OJ —, X ^ < tn a. — 1 O < z E < Q. a. < 2 OJ CO 2 J5 <n z o o GC O I ^ 2 _ •JJ -° 1 >- S Q UJ i X 3 t-h- Z cn UJ i ^ * o u UJ > UJ c re o ^- < a Z o o SM/Sq RED BROWN. CLAYEY SILTY 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 •r BG CK SM/SL BROWN CLAYEY SILTY SAND (TOPSOIL) MOIST ML GREEN BROWN, SANDY SILT MOIST MEDIUM DENSE STIFF d_ SM/ML I BG 5 6-4 YELLOW. RED, BROWN. SILTY SAND (WEATHERED DECOMPOSED GRANITE) MOIST MEDIUM DENSE SM YELLOW BROWN, SILTY SAND (DECOMPOSED GRANITE) MOIST MEDIUM DENSE TO DENSE 121.9 12.1 VERY DENSE TRENCH ENDED AT 8' SOUTHERN CALIFORNIA SOIL A TESTING,INC. SUBSURFACE EXPLORATION LOG SOUTHERN CALIFORNIA SOIL A TESTING,INC. LOGGED BY: CRB DATE LOGGED: T 5.82 SOUTHERN CALIFORNIA SOIL A TESTING,INC. JOB NUMBER: 9021049 Plate No. 7 — ; DEPT DEPT < ,1 I \ TRENCH NUMBER a. I — CO < OEE'ZP.iPTi.Z N — a: JJ — X Z < cn Q. — 3. O < z Z 2 - UJ < o. < CA W z o u UJ GC o 10 z _ UJ — > sc Q 3 ^— tn 5 z - z o z UJ o > — < UJ E O < a. Z o u BAG^M/SC CK 1 RED BROWN. CLAYEY SILTY SAND (TOPSOIL) MOIST MEDIUM DENSE — SM 1 i YELLOW BROWN, SILTY SAND (DECOMPOSED GRANITE) MOIST DENSE TO VERY DENSE — CK I i — CK 118.2 10.8 — TRENCH ENDED AT 8* — ! i TRENCH NUMBER '3-7 — 3- 6. 7 O-l pM RED BROWN. SILTY SAND MOIST MEDIUM (TOPSOIL) DENSE 1 _ CK — SM DARK GRAY, GRAVELY SILTY MOIST DENSE TO — 2^ SAND (DECOMPOSED GRANITE) VERY DENSE TRENCH ENDED AT 2' - — SOUTHERN CALIFORNIA SOIL A TESTING,INC. SUBSURFACE EXPLORATION LOG SOUTHERN CALIFORNIA SOIL A TESTING,INC. LOGGED BY: DATE LOGGED: ] 2-15-82 SOUTHERN CALIFORNIA SOIL A TESTING,INC. JOB NUMBER: 9021049 Plate No. 8 - I '-^ -.1 < I < I - TRENCH NUMBER — (X 'JJ — X Z < cn Q. — 2. O < z Ol I X < 1 Q- 1 < DEEGPIPTICN cn r o cn 2 UJ 3 X O Cfl 2 _ UJ — ° 1 >- X a UJ X 1- cn O Z 2 O o UJ o > — I. K (J < < -J a SM/ I RED BROWN. CLAYEY SILTY SC I SAND (TOPSOIL) MOIST MEDIUM DENSE GM GRAY, SANDY GRAVEL (METAVOLCANIC ROCK) :r BAGI MOIST DENSE TO VERY DENSE TRENCH ENDED AT 5 TRENCH NUMBER TQ-9 ,1- SM/ SC CL SM RED BROWN, CLAYEY SILTY SAND (TOPSOIL) MOIST CK BAGI GRAY BROWN. SANDY CLAY (WEATHERED DECOMPOSED GRANITE) MOIST MEDIUM DENSE STIFF YELLOW BROWN, SILTY SAND (DECOMPOSED GRANITE) MOIST DENSE TO VERY DENSE 128.1 10.1 TRENCH ENDED AT 6' SUBSURFACE EXPLORATION LOG LOGGED BY: DATE LOGGED: 12-15-82 JOB NUMBER: 9021049 Plate No.. 9 SOUTHERN CALIFORNIA SOIL ATESTING,INC. lOOrrr 90 ao 70 I 60 50 S 40 u 20 10 36" 16- 24V 12" 0 IOOO 4 12 2* _ 1 'i. U.S Standard Sieves J^" tio •20 "Mo iHiL) »t > (t « i6o * • I 4 S 4 S I Groin Sue (m m) Hydrometer (Minutes) & JO ISO »t7« S 4 1 Ul 34 I S !. 4 S 44Q Ol' IOU ;)Ci 60 70 t li 'It; 40' li 3(1 u 3 2 0 «, 1 0 — « 0 PARTICLE SIZE LIMITS GRAVEL SAND SILT OR CLAY BOULDER COBBLES Cooria Fin* Coort* 1 Mtdlum | Fln« (12 in.) 3 in. 3/4 In. U. S. No.4 No.lO STANDARD SIEVE SIZE TQ-2 @ 3' —_ TQ-2 P 4'-5' — . . .— TQ-8 0 r-S' ASTM D1557-78 METHOD A •:.AMPLE DESCRIPTION Maximum | Density (pet) Optimum 1 Moisture 1 Conte/.) 1 3 2'-3' Yellow Brown, Silty Gravelly Sand 114.8 13.8 1 TG-2 3 2'-3' Green Brown, Sandy Silty Clay 114.0 15.0 1 • D-2 (3 4'-5' Yellow/Reddish Brown, Silty Sand 112.6 14.8 1 *0-8 ? 3'-4' Grey, Silty Sandy Gravel 128.4 11.7 1 MAXIMUM DENSITY & OPTIMUM MOISTURE CONTENT EXPANSION TEST RESULTS 1 SAMPLE TQ-2 LJ 2'-3' TQ-2 @ 3'-4' CONDITION Remolded ' Remolded j • 'NITIAL M.C. C"/.) 16.1 H.8 ' ! ^ 1 irJITlAL ZZNSITY (PCFl 101.3 101.8 i i 1 "FINAL M.C. (•/.) 30.5 26.0 • NORMAL STRESS (PSF) 150 150 EXPANSION % 15.0 0 *? 0 . .J SOUTHERN CALIFORNIA SOIL A TESTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021049 DATE: 1-10-84 Plate No. 11 I I I I u. UJ £ )- CO s < UJ X 0) DIRECT SHEAR SUMMARY 2 2M L 2L NORMAL STRESS, KSF SAMPLE OESCRIPTION ANQLE OP INTERNAL FRICTION (•) COHESION INTERCEPT (psf) TQ-8@3'-4' Remolded to 90% 38 200 SOUTHBRN CALIPORNIA SOIL A TESTINQ,INC. CALAVERA HEIGH •T: KAR JOB NUMBtR . 9021049 S-VILLAGE W-X-Y DATE: 5-01-90 Plate No.12 o 0 z c Ul o H PI Ut H z o a 7^ (A o c H Z m o > r IB o o ro I—• o LO o o 3» m > Ln I _QY£flSlZ£_BQt:»^'^P-Q^'^^ ( blruclurul Soil - RocK Till ) P/L n> Ln I o OJ o X I -< •ons C0*V«Ctt4 toti nil IMII CMttlH it Ii4it 40 ptrcint tall lIlM Hl>(*l )/<-l«ck >Ut«, (b| •tight). 4nd k« co«^actH la accaratau MIU tfutricitloAi ror ilractaral fill. lacki a«ar • faat la aaalwa ^IMMIOA itot piraititd la rill. KCC MO lon A: Conpicled toll fill, hu rock trtqintnH over i Inchet In grtiitM diiwntlon. tONC I: ll<Klii I lo 4 fttt In mtttm^m diacfltlon pitced In >:iMP4Cled toll rill canruralnf lo IONC A. IONC C: laickt i Inthct lo t 'eel In mttlmtm diaenilon unUoraly dltlrlbu- Ifd 4nd well tptccd In coii««cltd toll MII conforalng la IOU «. IONC 0: Hequlred for tll eihling ilopei (:l «nd tlceper, 90( nlnlnu* cotytctlon, IONC A. I. or C ntlcrltl aty bc uted for IONC 0. NATURAL / GROUND BENCHINQ ^ CANYON SUBDRAIN DETAIL V/^ / ////// COMPACTED FILL //// /. />^J7^U/ / '/////////// /•/ /Jl" REMOVE UNSUITABLE MATERIAL SUBDRAIN TRENCH: SEE DETAIL AAB DETAIL A FILTER MATERIAL -e CUBIC FEET/FOOT FILTER MATERIAL SHALL BE CLASS 2 PERMEABLE MATERiAL PER STATE OF CALIFORNIA STANOARD SPECIFICATIONS. AND APPROVED ALTERNATE. CLASS 2 FILTER MATERIAL SHOULD COMPLY WITH THE FOLLOWING LIMITS PERFORATED PIPE 4 0 MINIMUM PERFORATED PIPE SURROUNDED WITH FILTER MATERIAL SIEVE SIZE 1 3/4 3/8 No. 4 Ntt. 8 Now 30 No. 60 No. 200 % PASSINQ 100 90-100 40-100 28-40 18-33 5-18 0-7 0-3 DETAIL B DETAIL OF CANYON SUBDRAIN TERMINAL 6 MIN OVERLAP DESIQN FINISH QRADE FILTER FABRIC (MIRAFI 140 OR APPROVED EOUIVALENT) 0 DETAIL \ 1 1/2 MAX QRAVEL OR / DETAIL B-1 APPROVED EQUIVALENT B-2 6 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 SOUTHERN CALIFORNIA CALAVERA HEIGHTS-VILLAGE W-X-Y y SOIL A TEI STING, INC. BY: KAR DATE: 5-03-90 \4/ JOB NUMBER: 9021049 Plate No. 14 SLOPE ST.-.BILI'Y CALCULATIONS Janbu's Simoiifiea Slooe Stability Method \C(p-WH Tend) FSrNcfC C ^ WH ' Assume Homoaeneous Strenath Parameters throuanout the slooe 38 Metavolcanic & Granitic Rock * Cut & Fill Slopes Cfpsf) W_(pcf) Incl H (ft) 200 130 2:1 35 2.2 Average Shear Strength Values Where: .fiT C W s H FS Angle of Internal Friction Cohesion (psf) Unit weight of Soil (pcf) Height of Slope (ft) Factor of Safety yv SOUTHBRN CALIPORNIA SOIL A TESTINQ,INC. CALAVERA HEIGHTS - VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021054 DATE: 5-03-90 Plate No. 15 TnANSVERSE WEAKENED PLANE JOINTS Q' ON CENTER (MAXIMUM) w w/2 w/2 ! \ -•0' SLABS IN EXCESS OF 10 FEET IN WIDTH SLABS' 5 TO 10 FEET IN WIDTH PLAN NO SCALE 2 I n TOOLED JOINT r/2 (6"X6--10/10> WELDED WIRE MESH \ WEAKENED PLANE JOINT DETAIL NO SCALE SOUTHERN CALIFORNIA SOIL L TESTINQ. INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BYi KAR JOB NUMBiRft 9021049 DATBi.. 5-03-90 Plate No. 16 WATERPROOF BACK OF WALL PER ARCHITECTS SPECIFICATIONS 3/4 INCH CRUSHED ROCK OR MARIDRAIN eooo OR EQUIVALENT QEOFABRIC BETWEEN ROCK ANO SOIL 4" DIAMETER PERFORATED PIPE HOUSE ON QRADE SLAB i HOUSE RETAINING WALL SUBDRAIN DETAIL NO SCALE i ^>/V SOUTHBRN CALIPORNIA i^E< SOIL A TESTINQ,INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021049 DATE: 5-03-90 Plate No. 17 RIPPABILITY iNDEX NO RIPPING SOFT MEDIUM HARD BLASTING 71 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 VELOCITY, FT./SEC. RESULTS TRAVERSE NO. S73-8 -PH. a b S73-9 rl. I I f I S73-1CS73-1:. ^ / h S73-1' S73-1 'h 'I \l S73-l( alb / 1 'OTE: THE ABOVE RESULTS ATTEMPT TO SHOW DEPTHS TO HORIZONS OF VARYING DENSITY IN DIFFERENT LOCATIONS OVER THE STUCf^ 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 *ROAOS AND STREETS; SEPT^ 1967. I^^W SOUTHERN CAUFORNIA TESTING LABORATORY. INC. • BpB^ C2S0 RIVEROALE STREET fl X^r tAN OtEOa CAUFORNIA 92120 • 714<aM134 CALAVERA HEIGHTS-VILLAGE W-X-Y 1 SEISMIC RESULTS BY DBA DATE ^-14-73 1 SEISMIC RESULTS JOBNO. 9021049 Plate No. 18 RIPPABILITY NDEX NO RIPPING SOFT MEDIUM HARD / PIT BLASTING / / FWPI A / / / 0 1000 2000 lO'OO 40b0 5000 6000 7000 BOOO 9000 10000 VELOCITY, FT/SEC. RESULTS TRAVERSE NO. OTE- THE ABOVE RESULTS ATTEMPT TO SHOW DEPTHS TO HORIZONS OF VARYING DENSITY IN DIFFERENT LOCATIONS OVER THE STUCTf AREA. SEISMIC TRAVERSE NUMBERS ^ REFER TO LOCATIONS PIDTED ON ATTACHED PLANS. THE RIPPABIUTY INOEX'lS A MODIFICATION OF CHARTS BY THE CATERPILLAR CO. AND ARTICLE IN 'ROADS AND STREETS; SEPT^ 1967. SOUTHERIM CALIFQRIMIA SOIL & TESTING LAB, INC. ••oo mvanoALB amMT •AN OIBOO, eAi.iranNiA aaiao CALAVERA HEIGHTS-VILLAGE W-X-Y I SEISMIC RESULTS •Y DBA X>B NO. 9021049 DATE 1-11-83 Plate No. 19 RIPPABILITY NDEX NO RIPPING SOFT MEDIUM HARD BLASTING 7- 2000 3000 4000 50 VELOCITY, 9000 10000 RESULTS TRAVERSE NO. GEDPH, a. Ul Q a Tb a I b a I b a I b a I & a It? NOTE: THE ABOVE RESULTS ATTEMPT TO SHOW DEPTHS TO HORIZONS OF VARYING DENSITY IN DIFFERENT LOCATIONS OVER THE STUDf AREA. SEISMIC TRAVERSE NUMBERS REFER TO LOCATIONS PiDTED ON ATTACHED PLANS. THE*RIPPABIUTY INDEX*IS A MODIFICATION OF CHARTS BY THE CATERPILLAR CO. ANO ARTICLE IN 'ROADS AND STREETS; SEPT. 1967. 1 SOUTHERN CALIFORNIA /LSEO SO"- &TESTINC3 LAB, INC. BAN OIBQO, CALIFORNIA BBIBO CALAVERA HEIGHTS -VILLAGE W-X-Y SEISMIC RESULTS BY DBA DATE 1-11-83 1 SEISMIC RESULTS JOB NO. 9021049 Plate No. 20 1 D8L CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 Seiamic Velocity DBL Ripper Performance • Multl 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 DSL CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 Seiamic Velocity TOPSOIL CLAY IGNEOUS ROCKS GRANITE 3A8ALT SEDIMENTARY ROCKS 3 HALE SANOBTONE 3ILTST0NE CLAYSTONE CONOLOMERATE METAMORPHIC ROCKS 3CHI8T SLATE RIPPABLE 14 15 DSL Ripper Performance • Multi or Single Shank No. 9 Ripper • Estimated by Seismic Wave Velocities SOUTHERN CALIFORNIA SOIL & TESTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BYi KAR JOB NUMBERt 9021049 DATE: 5-03-90 Plate No. 22 3aiamic Velocity • 1000 Dl 1N CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 3 J. 5 8 7 '0 11 12 13 14 TOPSOIL CLAY IGNEOUS ROCKS QRANITE BASALT SEDIMENTARY ROCKS SHALE SANDSTONE SLTSTONE CLAYSTONE CONOLOMERATE METAMORPHIC ROCKS SCHIST SLATE 15 TZZZZZZZ YZZZZZZZZZ TZZZZZZ2ZZZZZ RIPPABLE MAROMAL NON-RIPPABLE Dl 1 N Ripper Performance • Multl or Single Shank No. 9 Ripper • Estimated by Seismic Wave Velocities SOUTHERN CALIFORNIA SOIL S. -TESTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021049 DATE: 5-03-90 Plate No. 23 CALAVERA HEIOTTS VILLM^S W-X-Y, TAMARACK AND CXILLEX^E BOULEVARD, CARLSBAD RBCXHMENDED O^ING SPBCIFICATIONS - GENERAL PROVISIONS GOIERAL INlSfr The intent of these specifications is to establish procedures for clearing, conpacting natural ground, preparing areas to be filled, and placing and conpacting fill soils to the lines and grades shown on the accepted plans. The recomtendations contained in the preliminary geotechnical investigation report and/or the attached Special Provisions are a part of the Recommended 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 conminication signed by the Geotechnical Engineer. OBSERVATION AND TESTDC Southern California Soil and Testing, Inc., shall be retained as the Geotechnical Engineer to observe and test the earthwrk 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 accomplished 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 information and data so that 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 recomnendations. (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 weather, 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 accordance with the following American Society for Testing and Materials test methods: Maximum Density & Optiraum Moisture Content - ASIM 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 vM.ch is defined as natural soils which possesses an in-situ density of at leeist 90% of its naximum 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 competent formational soils. The lower bench shall be at least 10 feet wide or 1-1/2 times the the equipment width whichever is greater and shall be sloped back into the hillside at a gradient of not less than two (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 compacted natural ground. Ground slopes flatter than 20% shall be benched v*ien considered necessary by the Geotechnical Engineer. Any abandoned buried stjructures encountered during grading operations must be totally renoved. All underground utilities to be abandoned beneath any proposed structure should be removed 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 requirements 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 nay determine if emy special reconmendation will be necessary. All water wells v^ich 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 \4iichever 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 Structural 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 detrimental soils are covered in the geotechnical report or Special Provisions. Expansive soils, soils of poor gradation, or soils with low strength 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 GCMPACTION 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 moisture 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 conpact the layer. Conpaction equipment should either be specifically designed for soil conpaction or of proven reliability. The minimum degree of conpaction to be achieved is specified in either the Special Provisions or the reconnendations contained in the preliminary geotechnical investigation repoirt. When the structural fill material includes rocks, no rocks will be allov^ to nest and all voids must be carefully filled with soil such that the minimum degree of compaction recommended in the Special Provisions is achieved. The naximum size and spacing of rock permitted in structural fills and in non-structural fills is discussed in the geotechnical report, v*ien applicable. (R-9/89) SCS&T 9021049 May 15, 1990 Appendix, Page 5 Field observation and conpaction tests to estimate the degree of compaction 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 means of sheepsfoot rollers or other suitable equipment. Conpaction 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 traclcrolled. Steeper fill slopes shall be over-built and cut-back to finish contours after the slope has been constructed. Slope compaction operations shall result in all fill material six or more 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 compaction specified in the Special Provisions section of this specification. The conpaction operation on the slopes shall be continued until the Geotechnical Engineer is of the opinion that the slopes will be stable sttrficially stable. Density tests in the slopes will be made by the Geotechnical Engineer during construction of the slopes to determine if the irequired compaction is being achieved. Where failing tests occur or other field problCTis arise, the Contractor will be notified that day of such conditions by written comnunication from the Geotechnical Engineer or his representative in the form of a daily field report. If the method 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 nutigating measures are necessary. Unless otherwise specified in the geotechnical report, no cut slopes shall be excavated higher or steeper than that allovred by the ordinances of the controlling govemmental agency. ENGINEERING OBSERVKUGN 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 conpaction. SEASCK UMTES Fill shall not be placed during unfavorable veather conditions. When v\rork 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 RBOWMENraD C3«DING SPECIFICATIONS - SPECIAL PROVISIONS RELATIVE CCMP^CnON: 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 subgrade, the upper six inches should be conpacted to at least 95% relative conpaction. EXPAierVE SOILS: Detrimentally expansive soil is defined as clayey soil vAiich has an ejqjansion index of 50 or greater when tested in accordance with the Uniform Building Code Standard 29-C. OVERSIZED MKIERIAL: Oversized fill material is generally defined herein as rocks or lunps of soil over 6 inches in dianeter. 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. HUNSmON lOrrS: Where transitions betv^n 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 vrould be addressed in the geotechnical report, special footing reinforcement or a conbination of special footing reinforcement and undercutting may be required. (R-9/89)