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Home My WebLink AboutCT 00-02; CALAVERA HILLS PHASE II W-X-Y; INTERIM REPORT OF GEOTECHNICAL INV; 2000-08-11\o\VcfYi -^'^^^ INTERIM REPORT OF QBGTBCHNICAL IMVESnGATICN CALAVERA HEKJDS VILLBGES W-X-Y TAMARACK AND CQLLfXSE B0UU5VARD CARLSBAD, CALIFORNIA PREPARED FOR: Lyon Gcnnunitu.es, Incorporated 4330 La Jolla Village Drive, Suite 130 San Diego, Califomia 92122 PREPARED BY: Southem Califomia Soil & Testing, Inc. Post Office Box 20627 6280 Riverdale Stireet San Diego, Califomia 92120 R.ECFfVEj DIDO. CALIF. 92035 -746-4544. SOUTHERN CALIFORNIA SOIL AND TESTING, INC. 62B0 RIVERDALE ST. SAN DIEGO. CAUF. 92,20 • TELE 28-432, • P.O. BOX 20627 SAN D.EBO, CAUr. 92120 S7B ENTERPRISE ST. ESCON May 15, 1990 Lyon Communities, Incorporated 4330 La Jolla Village Drive Suite 130 San Diego, Califomia 92122 ATTEOTION: Mr. George Haviar SCS&T 9021049 Report No. 1 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 have conpleted an interim geotechnical investigation for the subject project. We are presenting herewith our findings and reconmendations. In general, we found the site suitable for the proposed development provided the reconnendations 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. Resp9qtf ully ^•ubmitted, SC ;STING, INC. Dani^ B. Adler, R.C.E. #36037 DBA:JRH:KAR:nw cc: (2) Sutmitted (4) Hunsaker and Associates (1) SCS&T, Escondido SOUTHERN CALIFORNIA ohn R. High, C.E.G AND TESTING. TABU: OF OONTEMTS PACE Introduction and Project Description 1 Project Scope ^ Findings Site Description ^ General Geology and Subsurface Conditions 3 Geologic Setting and Soil Description 3 1) Basenent 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 ^ Geologic Hazeuxls ^ Groundshaking ^ Seismic Survey and Rippability Characteristics 8 General ^ Rippability Characteristic of Granodioritic 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 1-4 Groundwater Conclusions and Reconmendations 16 General Grading Site Preparation ^7 Select Grading Cut/Fill Transition 17 Imported Fill 18 Rippability 1^ Oversized Rock 18 Slope Construction 18 Surface Drainage 18 Subdrains 19 Ecurthwork 19 Slope Stability 19 Foundations 19 General 19 Reinforcement 20 Interior Concrete Slabs-on-Grade 20 Exterior Concrete Slabs-on-Grade 21 Special Lots 21 Expansive Characteristics 21 Settlement Characteristics 21 Earth Retiaining Walls 22 Passive Pressure 22 Active Pressure 22 TABLE OF CdMrEMTS (continued) PA£3; 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 ATEBCHMENIS 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 PLATES 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 Weatened Plane Joint Detail 17 Retiaining Wall Subdrain Detail 18-20 Seismic Line Traverses 21-23 Catepillar Rippability Charts APPEM5IX Recomiended Grading Specification and Special Provisions SOUTHERN CAU.F-ORN.A SO.U AND TESTING. INC. S2B0 mVEROALE ST. SAN D.EGO, CAUr. 92,20 • TELE2B0.432, • P.O. BOX 20627 SAN 0,E30. CALT. 92, 20 EN.ERPR.SE ST. ESCON o.OO. C.L,.. ,.O.S • TELE , S.. DHERIM REPORT OF GEOTECHNICAL INVESTIGBTICN CALAVERA HEIGHTS VILLAGES W-X-Y TAMARACK AND COLLEGE BOULEVARD CARLSBAD, CALIFORNIA INTRDDOCnON 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 Number 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 tvo stories high and of vood 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. To assist with the preparation of this report, v^ were provided with a grading 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 CALIFORNIA SOIL AND TESTING. IN C SOUTHBRN CALIFORNIA CALAVERAS HEIGHTS-VILLAGE ^1^^ SOIL A TBSTINQ,INC. •T: KAR/EM DATI: 5-15-90 JOB NUMScn: 9021054 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 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 stibsurface 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 developnent of the proposed svibject site. c) Describe the rippability characteristics of the existing rock. d) Define the general geology at the site including possible geologic hazards v*iich could have an effect on the site development. e) Develop soil engineering criteria for site grading and provide recomtendations regarding the stability of proposed cut and fill slopes. f) Address potential construction difficulties and provide reconmendations conceming these problems. SCS&T 9021049 May 15, 1990 Page 3 g) Reconmend an appropriate foundation system for the type of structures anticipated and develop soil engineering design criteria for the reconmended foundation design. FINDIN3S SITE rascRipnoN The subject site is an irregular shaped parcel of land, designated as Villages W, X and Y within the Calavera Heights developnent in Carlsbad, Califomia. The subject site covers approximately one hundred acres and is bounded on the sout:h, east and north by undeveloped land and by residential housing and undeveloped land on the west. Topographically, the site is located in hilly terrain witJi well developed, large, drainage coxirses 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 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 shnjbs and small trees within the large drainage coxirses. Overhead power lines traverse the site in a southwest to northeast direction. The site is undeveloped, with the exception of the power lines. GEa^ERAL GBOUOGI AND SUBSURFACE CONDITIONS GBQDUOGIC SEITING AND SOIL DESCRIPTION: The subject site is located near the boundary between the Foot±iills 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 conplex rocks consisting of Jurassic-age netavolcanic rocks. Cretaceous-age granitic roclcs, 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 Page 4 1) BASEMENT OWPLEX - JURASSIC METAVOLCANICS AND CRETEflCECOS GRANITICS (Jitiv/Kgr): The oldest rocks exposed at the site are the Jurassic metavolcanic 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 intrusive rocks found at the site. Both the netavolcanics and the associated hypabyssal rocks weather to dark, snooth 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 basenent conplex 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 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, nedium 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 ccfmrnonly contain areas v^ich 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 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 where given a dual classification. The boundaries between the basement rock types are very irregular, therefore they were not differentiated on Plate Nunter 1. 2) SANTIAGO PORMKnON (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 t±e Santiago Formation. 3) OLCER QUATERNARY (PUEISTOCENE) 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) TOUNCaaR QUMERNARY (HOLOCENE) 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 cont>ined thickness. Table I presents sone of the pertinent engineering characteristics of the materials at the site. TABLE I (3WERALIZED ENGINEERING CHARACTERISTICS OF MAIN GEOLOGIC UNITS Unit Name and Syntool Rippability Amount of Oversize Material Slope Stability/ Erosion Conpressibility Expansive Potential Granitic Rocks- Kgr (Granodiorite) Generally Rippable to + 15 Feet Low to Moderate Good Nominal Nominal Granitic Rocks- Kgr (Tonalite) Marginally Rijpable to Nonrippable Moderate to High Good Nominal Nominal Metavolcanic and Hypabyssal Rocks-Jmv Marginally Rippable to Nonrippable 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 Rifpable Nominal Moderately Erodible Moderate to Hiqh Low to Hiqh SCS&T 9021049 May 15, 1990 Page 7 TBCrCNIC SEmNG: 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 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 approxinately 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 v^st of the site. The Rose Canyon Fault Zone comprises 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 west, the Agua Bianca and San Miguel Fault Zones to the south, and the Elsinore and San Jacinto Fault Zones to the northeast. mjLOSLC HAZARDS: The site is located in an area v*uch is relatively free of potential geologic hazards. Hazards such as tsunamis, seiches, liquefaction, and landsliding should be considered negligible or nonexistent. SCS&T 9021049 May 15, 1990 Page 8 OOUNDSHAKING: One of the nost likely geologic hazards to affect the site is groundshaJcing 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 sunmarized in the following Table II. TABLE II Fault Zone Maximum Probable Distance Bedrock Design Acceleration Acceleration 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 nagnitude 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 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 RIPPABILITY CHARACTERISTICS GSaiERAL: 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 sunmary of each seismic traverse is presented in Table III SCS&T 9021049 ttoy 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: 50 Feet Geologic Unit: Metavolcanic Interpretation: 0'- 3' Rippable 3'-17' Rippable with Hardrock Floaters 17'-30' Nonrippable SeLsmic 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'-27' Nonrippable Seismic Traverse No. SW-IIR Proposed Cut: None Geologic Unit: Metavolcanic Interpretation: 0'- 6' Rippable 6'-27' Nonrippable SCS&T 9021049 May 15, 1990 Page 10 TAHLE 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 + 21' Nonrippable Seismic Traverse No. SW-12R Proposed Cut: Geologic Unit: Interpretation: 29 Feet Metavolcanic 0'- 5' Rippable 5'- 26' Rippable with Hardrock Floaters + 26' Nonrippable Seismic Traverse No. SW-13 Proposed Cut: Geologic Unit: Interpretation: 13 Feet Metavolcanic 0'- 4' Rippable 4'-15' Rippable with Hardrock Floaters + 15' Nonrippable Seismic Traverse No. SW-14 Proposed Cut: Geologic Unit: Interpretation: 38 Feet Metavolcanic 0'- 4' Rippable 4'-21' Rippable with Hardrock Floaters + 21' Nonrippable Seismic Traverse 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 Metavolcanic 0'- 6' Rippable 6'-15' Rippable with Hardrock Floaters + 15' Nonrippable Seismic Traverse No. SX-15R Proposed Cut; Geologic Unit: Interpretation: Unknown Metavolcanic O'-ll' Rippable + 11' Nonrippable Seismic Traverse No. SZl-16 Proposed Cut; None Geologic Unit: Granitic Interpretation: 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: Geologic Unit: Interpretation: Unknown Metavolcanic/Granitic 0'- 5' Rippable + 5' Nonrippable SCS&T 9021049 May 15, 1990 Page 12 TABLE III (continued) Seismic Traverse No. SZ2-17R Proposed Cut; Unknown 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 approxinately 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 naterial 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 more fine naterial and to facilitate the mixing of soil and rock to be used as fill. RIPPABIUTY CHARACTERISTIC OF CSWNODIORITIC ROCK RIPPABLE CGNDinON (0-4,500 FT./SBC.): This velocity range indicates rippable materials which may consist of deconposed granitic rock possessing random hardrock floaters. These naterials will break down into slightly silty, well graded sand, whereas the floaters will require disposal in an area of nonstructural fill. Some areas containing nunerous hardrock floaters nay present utility trench problems. Further, large floaters exposed at or near finish grade may present additional problems of removal and disposal. 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 equipnent. MARGINALLY RIPPABLE CGNDITION (4,500 FT./SEC.-5,500 FT./SBC.): This range is rippable with effort by a D-9 in only slightly weathered granitics. This velocity range nay 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 equipnent. Difficulty of excavation would also be realized by gradalls and other heavy trenching equipment. NONRIPPABLE COHJITIGN (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 material requiring disposal in areas of nonstructural fill. This upper limit has been based on the Rippability Chart shown on Plates Nuntoer 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.TTY CHARACTERISTICS OF METAVOLCANICS AND ASSOCIATED HYPABYSSAL ROCKS AND TONALITIC ROCKS RIPPABLE CONDITION (0-4,500 FT./SBC.): This velocity range indicates rippable materials v^ich may vary from deconposed netavolcanics 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" 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./SBC.): Excavations in this velocity range would be extremely time consuming and would produce fractured rock with little or no fines. The higher velocities could require blasting. Trenching equipment would not function. NDNRIPPAHLE CONDITION (5,500 FT./SBC. & GREATER): This velocity range may include ntxierately to slightly fractured rock v^ich 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 LIMITATIONS 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 assuned to possess similar characteristics. SCS&T 9021049 May 15, 1990 P^g^ 1^ 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 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) Wfeathering 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 ripping of higher velocity materials may become totally dependent on the tiire available and the economics of the project. Ripping of higher velocity materials can be achieved but it nay becone 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 subdrains be installed within drainage swales which are to receive fill. It should be realized that groundwater problems may occur after development of a site even where 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 development, it is our opinion that any seepage problems which nay occur will be minor in extent. It is further ovu: opinion that these problems can be most effectively corrected on an individual basis if and v^en they develop. CONCLUSIONS AND RECOMMENDATIONS C3MERAL In general, no geotechnical conditions were encountered which vrould 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 development include hard granitic, metavolcanic, and hypabyssal rock, v*iich 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, importing of fine materials or exporting excess rock may be necessary. Existing loose surficial deposits such as topsoils, subsoils, younger alluvium, and any weathered formational naterials encountered are considered unsuitable for the support of settlement sensitive inprovements, and will require removal and/or replacement as conpacted fill. Expansive soils were also present within the subject area. Where possible, select grading is reconmended to keep nondet:rinentally expansive soils witJiin four feet from finish pad grade. In areas where this is not feasible, special foundation consideration will be necessary. However, it is anticipated that only minor amounts of expansive soils vdll be encountered. SCS&T 9021049 GRADING 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 detennined 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 improvements. SELECT C3»DI1IG: 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 more. Select material should consist of granular soil with an expansion index of less than 50. It is reconmended 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. COT/FILL TRAIBrnaN: It is anticipated that a transition line between cut and fill soils may run through sone 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 reconmend 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 minimim horizontal limits of these reconmendations should extend at least five feet outside of the proposed inprovements. IMPORrED FILL: All fill soil imported to the site should be granular and should have an expansion index of less that 50. Further, import 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. RIPPABILrTr: 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 summarized 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 v*iere deep cuts are proposed. OVEIBIZED HOCK: Oversized rock is defined as material exceeding six inches in maximum dinension. It is anticipated that oversized naterial will be generated from proposed cuts. Oversized material nay be placed in stmctural fills as described in Plate Nuntoer 13. SLOPE CONSTRUCnCN: 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 perfonned 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 reconmended 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 Nuntoer 14. EARTHWCWK: All earthwork and grading contenplated for site preparation should be acconplished in accordance with the attached Reconmended Grading Specifications and Special Provisions. All special site preparation reconmendations 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 structures and beneath asphalt pavenents should be conpacted to minimum of 90% of its naximum 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 naterial and should not be part of the mass grading requirenents. 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 STABTT.TTY Proposed cut and fill slopes should be constructed 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 vdll possess an adequate factor of safety with respect to deep seated rotational failure and sxirficial failure (see Plate Number 15). The engineering geologist should observe all cut slopes during grading to ascertain that no adverse conditions are encountered. FOllCtKTIGNS (SKERAL: If the lots are capped with nondetrimentally expansive soils, conventional shallow foundations may be utilized for the support of the proposed st:mctures. 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-tvro-story construction, respectively. A minimum width of 12 inches and 18 inches is reconmended 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. Reconmendations for expansive soil conditions will be provided after site grading when the expansion index and depth of the prevailing foundation soils are known. REINPCW3EMENT: 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 reinforcenent is based on soil characteristics and is not intended to be in lieu of reinforcenent necessary to satisfy structural 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 reinforcement should be placed near the middle of the slab. As an altemative, the slab reinforcing may consist of 6"x6"-W1.4xW1.4 (6"x6"-10/10) velded wire mesh. Hovrefver, 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 crushed rock should be placed under the slab. This SCS&T 9021049 May 15, 1990 P^^e 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 pen:ent 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. EXIERIOR SLABS-ON-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 mesh and provided with weakened plane joints. Any slabs betv^n 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 constructed 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 LCrrS: Special lots are defined as lots underlain by fill with differential thickness in excess of ten feet. The following increased foundation reconmendations 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 vreathers to a clayey subsoil, and its presence within four feet of finish pad grade will require special site preparation and/or foundation consideration. SETTLEMENT CHMWCTERISnCS: The anticipated total and/or differential settlenents for the proposed stmctures may be considered to be within SCS&T 9021049 May 15, 1990 Page 22 tolerable limits provided the reconmendations 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 nomal and may be anticipated. EARffl REHMNING WALLS PASSIVE PRESSURE: The passive pressure for the prevailing soil conditions nay be considered to be 450 pounds per square foot per foot of depth up to a naximum of 2000 psf. This pressiire 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 movement. 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 structures with level backfills may be assumed to be equivalent to the pressure of a fluid weighing 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 Nunter 17. BACKFILL: All backfill soils shouid be conpacted to at least 90% relative conpaction. Expansive or clayey soils should not be used for backfill naterial. The wall should not be backfilled until the masonry has reached an adequate strength. FICKJR 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 uanTmoNS REVIEW, OBSERWAnCN AND TESTING The reconnendations presented in this report are contingent upon our review of final plans and specifications. Such plans and specifications should be nade available to the geotechnical engineer and engineering geologist so that they nay review and verify their conpliance 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 reconnendations and to allow design changes in the event that subsurface conditions differ from those anticipated prior to start of constmction. UNIFORMITY OF COHDITICNB 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 perfomance 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. CHPtfX, IN SCOPE 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 nodi fied by a written addendum. SCS&T 9021049 TIME LIMITATIONS 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 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 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 reconmendations. PROFESSIONAL SIRM3ARD In the performance of our professional services, we comply 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 that subsurface conditions may vary from those encountered at the locations where our trenches, surveys, and explorations are nade, and that our data, interpretations, and reconmendations 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 oniy, and no warranty of any kind whatsoever, express or implied, is made or intended in connection with the work performed 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. CLIENT'S RESPOeiBILITY It is the responsibility of Lyon Communities Incorporated, or their representatives to ensure that the infomation 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 were 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 Number 3 through 6). In addition. Plates Nunter 7 through 9 from the referenced reports contain additional trench excavations made 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 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 simplified 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. LABC«ATORy TESTING Laboratory tests were performed in accordance with the generally accepted Anerican Society for Itesting and Materials (ASTM) test methods or suggested procedures. A brief description of the tests performed is presented below: a) CLASSIFICKTION: 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) fDISTURE-EENSITY: 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 naterial consistency with depth. The dry unit weight is determined in pounds per cubic foot, and the in-place moisture content is determined as a percentage of the soil's dry weight. The results are summarized in the trench logs. c) caiAIN SIZE DISTRIBOTICII: The grain size distribution was determined for representative samples of the native soils in accordance with ASTM D422. The results of these tests are presented on Plate Number 10. d) COMPACTION TEST: The naximum 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 Nunter 11. e) EXPANSION lEST: The expansive potential of clayey soils was detemiined in accordance with the following test procedure and the results of these tests appear on Plate Number 11. Allow the trinned, 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 moisture to contact the sanple and neasure its expansion from an air dried to saturated condition. f) DIRECT SHEAR TESTS: Dijrect shear tests vere performed to determine the failure envelope based on yield shear s1:rength. The shear box was designed to accommodate a sanple 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 were 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 metavolcanic rock are presented on attached Plate Number 12. SUBSURFACE EXPLORATION LEGEND UNIFIED SOIL CLASSIFICATION CHART SOIL DESCRIPTION I. 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 GU 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 AND CLAYS Liquid Limit less than 50 SILTS AND CLAYS Liquid Limit greater than 50 GP GM GC SW SP SM SC ML CL OL MH CH OH HIGHLY ORGANIC SOILS PT :YP!:AL NAMES Well graded gravels, gravel- sand mixtures, little or no fines. 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 oiasticity, 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 yv SOUTHERN CALIFORNIA SOIL A TESTING, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y yv SOUTHERN CALIFORNIA SOIL A TESTING, INC. BY: KAR/EM DATE: 5-03-90 yv SOUTHERN CALIFORNIA SOIL A TESTING, INC. JOB NUMBER: 9021049 Plate No. 2 Class TRENCH ::0. IT-50 Description I SM Gray-brown, Moist, Dense to Very Dense, Siltv Sand (Decomposed Granite) Trench Ended at 4 Feet yf\ SOUTHERN CALIFORNIA XSLS SOIL & TEBTINQ , INC. BAN oiana, CALIFORNIA ••^•O CALAVERA HEIGHTS-VILLAGE W-X-Y BY CRB DATE 12-21-82 JOB NO. 9021049 Piatt: No. 3 SOUTHERN CALIFORNIA SOIL & TESTING , INC. •••O RIV«ROAI.« •TR««T •AN Ol««0. CAUiPORNIA •«1«0 CALAVERA HEIGHTS-VILLAGE W-X-Y BY OATE 12-21-82 ll '•A A A. r.ed-brov.m, iiitv -:i:-iG !'.:ist. !ledium uense. s:i/ sc / ^sc/ CL 10 Vellov;-bro\<m , ...ia-'.irown. J i-av-oro\v.'n. Moist, :!ediun jense. Clavev Siltv riand. Porous (Older .Viluviun) Sandv Clav/Clavev Sand Trencn r.adea at 10 Feet 113.2 8.0 10 / .8 15.5 /V SOUTHERN CALIFORNIA ^fX SOIL & TESTINQ , INC. sX/ BAN oiaao, CAUiraRNiA ••^•o CALAVERA HEIGHTS-VILLAGE W-X-Y BY CRB OATE 12-21-82 JOB NO. 9021049 Plate :'o. 4 I UJ a > Ul -I a. Z < z o < o o t < GM GM TRENCH NUMBER ELEVATION TX-77 DESCRIPTION BROWN SANDY GRAVEL (TOPSOIL) GRAY BROWN SANDY GRAVEL (METAVOLCANIC ROCK) I REFUSAL AT 2.5' TX-78 CL BROWN SILTY CLAY (TOPSOIL) 2 - GM CL GM J GRAY BROWN SANDY GRAVEL I(METAVOLCANIC ROCK) REFUSAL AT 3' RENCH NUMBER X-79 BROWN SILTY CLAY (TOPSOIL) GRAY BROWN SANDY GRAVEL (METAVOLCANIC ROCK) REFUSAL AT 3' I- Ul 2 ec UJ 3 oc H < v> t o < z HUMID/ MOIST HUMID MOIST HUMID MOIST HUMID z Ui oc < a. a. < > Ul (A H Z U) UJ « o z c o o o MEDIUM DENSE VERY DENSE STIFF VERY DENSE STIFF VERY DENSE in z UJ a > tr o IU IC 3 U o s z UJ O o UJ > UJ OC z o O < a. 2 O o SOUTHERN CALIFORNIA SOIL ATESTIHG,INC. UBSURFACE gXPlORATION LOG D^^^ 7-18-83. S LOGGED BY CRB JOB NUMBER: 9021049 I i RENCH NUMBER 15 z 1 T < I C 1 _ ^ _ 2 V) < OESOF. iPTlCN SM/Sa RED BROWN. CLAYEY SILTY ' SAND (TOPSOIL) ^ oc X K < Ml a. — X O < Z MOIST TO WET UJ X < 0. a 2 _ Ol (A Z UJ a z O oc O z UJ a > X a MEDIUM DENSE UJ X t— M 5 s z UJ t-z o u UJ > UJ K O o < a. O (J RED, BROWN. GRAY, SANDY CLAY (WEATHERED DECOMPOSED GRANITE) WET MEDIUM STIFF — YELLOW BROWN, SILTY GRAVELY MOIST DENSE TO VERY DENSE — C 1 0 2 < TRENCH NUMBER -o < I - ^ ! 5 I 1 CO , •EEC-i - a: JJ — X Z < V) a. — X O < 2 Ul X < a. CL < z dJ f— tf) z o u UJ a X O CO z _ Ul — ° 1 >- X o ^. z « UJ — O 2 z O z Ul o > — a. 2 o BAGSM/SC C;: I RED BROWN. CLAYEY SILTY SAND (TOPSOIL) MOIST MEDIUM DENSE SM 3- 4_ CK 6_ 7 8 CK YELLOW BROWN, SILTY SAND (DECOMPOSED GRANITE) MOIST DENSE TO VERY DENSE 118.2 10.8 TRENCH ENDED AT 8' TRENCH NUMBER 0-( 1 2 CK SM RED BROWN. (TOPSOIL) :LTY SAND -MOIST MEDIUM DENSE DARK GRAY, GRAVELY SILTY SAND (DECOMPOSED GRANITE) MOIST DENSE TO VERY DENSE TRENCH ENDED AT 2' y\. SOUTHERN CALIFORNIA SOIL & TESTING,INC. SUBSURFACE EXPLORATION LOG y\. SOUTHERN CALIFORNIA SOIL & TESTING,INC. LOGGED BY: ^j^g DATE LOGGED: 12-15-82 y\. SOUTHERN CALIFORNIA SOIL & TESTING,INC. JOB NUMBER: 9021049 Plate No. 8 TRENCH NUMBER ' :5 I •SI I — — X 'JJ — X K < w o. — X O < 2 K < a. 0. • ESCP.IPTIC N cn z o (rt z X O Crt z _ UJ — ° 1 X a Ul 1. X >- z (rt UJ 5 O O Ul > Ul X o < 2 O u SM/ I RED BROWN. CLAYEY SILTY SC I SAND (TOPSOIL) MOIST MEDIUM DENSE GM T BAG) 1 GRAY, SANDY GRAVEL (METAVOLCANIC ROCK) MOIST DENSE TO VERY DENSE TRENCH ENDED AT 5' TRENCH NUMBER TQ-9 1 t- SM/ SC CL SM CK BAq RED BROWN, CLAYEY SILTY SAND (TOPSOIL) MOIST 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 5' SOUTHERN CALIFORNIA SOIL&TESTING,INC. SUBSURFACE EXPLORATION LOG LOGGED BY: Q^Q DATE LOGGED: 12-15-82 JOB NUMBER: 9021049 Plate No.. 9 o 73 > N m o 70 CD C H O Z 5 TO 1 O I 00 0 Pi z E o r-3> m m t—4 CD Ln I tn I X I -< US Standard Sieves !• ^2' 'A- •to #20 »J0 Ko J 21 - -lil W, *> "H iCO Hydromet er (MinulasJ W ISO S « S 2 9a I s !, 4 I4<(1 / ill ,)., I - (tu :KI 6U 70 \ -Idl <.; O 20 I o o V u o — <» PARTICLE SIZE T— BOULDERiCOBBLES 1 GRAVEL SANO SILT OR CLAY T— BOULDERiCOBBLES 1 Coorit j Fina CoorM 1 Mtdlum | Fina SILT OR CLAY 3'" 3/41n. No.4 No.lO No.40 No. 200 U. S. STANDARD SIEVfc SIZE TQ-2 @ 3' • TQ-2 @ 4'-5' — • • TQ-8 0 4 '-5' I I I MAXIMUM DENSITY & OPTIMUM MOISTURE CONTENT .ASTM D1557-73 METHOD A lAMPLE DESCRIPTION Maximum | Density (pcti Optimum Moisture Cont (•/.) -3' i Yellow Brown, Silty Gravelly Sand 114.8 13.8 C-2 9 2' -3' Green Brown, Sandy Silty Clay 114.0 15.0 3-2 @ 4' 1-1 1 Yellow/Reddish Brown, Silty Sand 112.5 14.8 0-3 9 3' -4' { Grey, Silty Sandy Gravel 128.4 11.7 i EXPANSION TEST RESULTS SAMPLE TQ-2 2'-3' TQ-2 (3 3'-4' C3NDITION Remolded { Remolded | 1 1 •NITIAL M.C. (•/.) 1 16.1 \ U.8 1 1 iMTlAL ZEMSITY CPCF 101.3 101.8 I FiNAL M.C. (•/.) 30.5 26.0 ! NORMAL STRESS (PSF) 150 150 EXPANSION % lE.C O "? 0. o SOUTHERN CALIFORNIA CALAVERA HEIGHTS-VILLAGE W-X-Y ^ SOIL A TESTING, INC. BY: KAR DATE: 1-10-84 ^ SOIL A TESTING, INC. JOB NUMBER: 9021049 Plate No. 11 DIRECT SHEAR SUMMARY (O IU flC QC < UJ X (A 2 2M L 2L NORMAL STRESS, KSF SAMPLE DESCRIPTION ANQLE OP INTERNAL FRICTION (•) COHESION INTERCEPT (psf) TQ-8@3'-4' Remolded to 90% 38 200 I yv SOUTHERN CALIFORNIA SOIL A TESTINQ,INC. CALAVERA HEIGH •T: KAR JOB NUMBeR . 9021049 S-VILLAGE W-X-Y DATE: 5-01-90 Plate No. 12 o r P» H ill W H Z O z o (A o c H Z m a o > r O o m z c K • m VXD o ro I—• o ot fi-ro to 7^ 33 I O to I CXJ O o m > tn to > I X I -< .DVtfiSIZfL-fiQCK-i^lSRQSAL ( Slruclurul Soil - Rock Till ) P/L 4 min- ZONE D W "Bf' a • G 12' 'min ^ Co<v«Cttd toll fill Ihtll CMl«U It Iftit 40 ptrctnt tall tliat Hi>l«l )/4-l«ck ilata, {*>j •ilfht). tntf ba coaatcta^ la accar^taca «IU tyttUUtilMi for itrMCtartl fill. lackt a«ar 4 taat la atalMi <taaailoA not ptraltud la nil. 20NC A: CotipJCI«l toll fill, hu roct Inqmtnn over 6 Inchet In greitetl aiMextlon. lUNC I: Rockt 2 lo 4 feet In atilmua dt*«fltlon pltccd In cuaptcled toll rill conluralng lo {ONC A. IONC C: (a<ki i Inchet to 2 feel In attliaM diaenilon unlforaly dltlrlbu- • cd tnd M«ll iptced In coisitcled toll fill coafarala, le I0t( k. IONC 0: Haqulrcd for tll eililln, tlopet (:l tnd ticeptr, 90t alnlaua coivitcllon. lONt A. I. or C atlcrltl aty ba uted far IONC 0. CANYON SUBDRAIN DETAIL NATURAL/ GROUND NI,\/> BENCHING ^ '//;/////////////.'/////L //// COMPACTED FILL ' ' ' / /J'// i'////.^//////////l,''ff/y ^-^isr-yii'//. REMOVE UNSUITABLE MATERIAL SUBDRAIN TRENCH: SEE DETAIL AAB DETAIL A FILTER MATERIAL e CUBIC FEET/FOOT 4 BEDDING PERFORATED PIPE 4 0 MINIMUM PERFORATED PIPE SURROUNDED WITH FILTER MATERIAL 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 SIEVE SIZE 1 3/4 3/8 No. 4 No. 8 Now 30 No. 60 No. 200 % PASSING 100 90-100 40-100 2S-40 18-83 5-15 0-7 0-8 DETAIL B DETAIL OF CANYON SUBDRAIN TERMINAL e MIN OVERLAP FILTER FABRIC MIRAFI 140 OR APPROVED EQUIVALENT) DESIGN FINISH GRADE 0 •AQ 1 DETAIL \ B-1 1 1/2 MAX QRAVEL OR / OETAIL APPROVED EQUIVALENT B-2 6 CUBIC FEET/FOOT NON PERFORATED 4'MIN PIPE PERFORATED 4 MIN 1 1/2"QRAVEL WRAPPED IN FILTER FABRIC ISUBDRAIN INSTALLATION'-SUBDRAIN PIPE SHALLBE INSTALLED WITH PERFORATIONS DOWN ISUBDRAIN 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 SOIL & TESTING,INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021049 DATE: 5-03-90 Plate No. 14 SLOPE STABILITY CALCULATIONS Janbu's Simoiifiea Slooe Stability Method FSrNcf(-C WH •) Assume Homoaeneous Strenath Parameters throuanout the slooe -er (°) 38 Metavolcanic & Granitic Rock * Cut & Fill Slopes C(psf) W. (pcf) Incl H (ft) 200 130 2:1 35 2.2 * Average Shear Strength Values Where: .0' C w s H FS Angie of Internal Friction Cohesion (psf) Unit weight of Soil (pcf) Height of Slope (ft) Factor of Safety y^Nv SOUTHBRN CALIFORNIA SOIL A TESTINQ,INC. CALAVERA HEIGHTS - VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021054 DATE: 5-03-90 Plate No. 15 i TRANSVEnSE WEAKENED PLANE JOINTS Q' ON CENTER (MAXIMUM) WCAKCNCD PLANE jaNTS Iff W/2 w/2 ! i 1 1^ \ SLABS IN EXCESS OF 10 FEET IN WIDTH SLABS' 5 TO 10 FEET IN WIDTH PLAN NO SCALE n TOOLED JOINT i ,-V4l If ' ^ , (6"x6"-1 r/2 OnO) WELDED WIRE MESH v r: WEAKENED PLANE JOINT DETAIL NO SCALE SOUTHERN CALIFORNIA CALAVERA HEIGHTS-VILLAGE W-X-Y 1 SOUTHERN CALIFORNIA N^T^ SOIL L TESTINQ, INC. BYI KAR DATSt 5-•03-90 1 N^T^ SOIL L TESTINQ, INC. JOS NUMBERt 9021049 Plate No. 16 1 i i i i I- WATERPROOF BACK OF WALL PER ARCHITECTS SPECIFICATIONS 3/4 INCH CRUSHED ROCK OR MARIDRAIN 9000 OR EQUIVALENT QEOFABRIC BETWEEN ROCK AND SOIL 4" DIAMETER PERFORATED PIPE QRADE SLAB HOUSE RETAINING WALL SUBDRAIN DETAIL NO SCALE SOUTHERN CALIFORNIA I SOIL A TESTINQ, INC. CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR JOB NUMBER: 9021049 DATE: 5-03-90 Plate No. 17 DiPPARlMTY INDEX BLASTING 0 ' 10t)0 • 2o'oO ' lo'oO ' 4O00 ' SOIDO 6CO0 7000 8000 9000 IOOOO VELOCITY, FT./SEC- RESULTS TRAVERSE NO. 6 >PH Q. Ul I •nTP- THE ABOVE RESULTS ATTEMPT TO SHOW DEPTHS TO HORIZONS OF VARYING DENSITY .N m^E^^^TlONS OVER THE STUO. AREA. SEISMIC TRAVERSE NiiMBPRS REFER TO LOCATIONS PLDTED ON ATTACHED PLANS. TSI*R.^BII^Y INSEX'IS A MODIFICATION OF CHARTS BY THE CATERRLLAR CO. AND ARTICLE IN 'ROADS AND STREETS; SEPT, 1967. SOUTHERN CAUFORNIA TESTING LABORATORY. INC 62S0 RIVERDALE STRKT IAN OlCOa CAUFORNIA 92120 714-2SM134 SEISMIC RESULTS CALAVERA HEIGHTS-VILLAGE W-X-Y BY DBA JOB NO. 9021049 DATE 4-14-73 Plate No. 18 RIPPABiLlTY iNDEX NO RIPPING SOFT MEDIUM -!ARD BLASTING / / / / / A / PT / / / 1^ A 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 VELOCITY, FT./SEC. RESULTS TRAVERSE NO. 3PH a. LU .r ^'OTE: THE ABOVE RESULTS ATTEMPT TO SHOW DEPTHS TO HORIZONS OF VARYING DENSITY INDIFFERENT LOCATIONS OVER THE STUDf AREA. SEISMIC TRAVERSE NUMBERS^ REFER TO LOCATIONS PLDTED ON ATTACHED PLANS. THE*RIPPABIUTY INDEX'lS A MODIFICATION OF CHARTS BY THE CATERRLLAR CO. AND ARTICLE IN 'ROADS AND STREETS; SEPT 1967. SaUTHEHIM CALlFORiMIA "CSL-^S SOIL & TESTIMG LAB, IIMC. •••a nivaROAi.a •TnaiT SAN oiaoo. CACi^aniMiA Baiao CALAVERA HEIGHTS-VILLAGE W-X-Y SEISMIC RESULTS >Y DBA JOB NO. Qn?indQ OATE 1-11-83 RIPPABILITY NDEX SOFT MEDIUM HARD BLASTING 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 VELOCITY, FT./SEC. RESULTS TRAVERSE NO. GBOPH CL llJ Q a i& 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 PIJDTED ON ATTACHED PL^NS. THE*RIPPABIUTY INDEX*IS A MODIFICATION OF CHARTS BY THE CATERRLLAR CO. AND ARTICLE IN 'ROADS AND STREETS; SEPT, 1967. /V SOUTHEHM CALIFOPNIA XSQ\ SOIL & TESTING LAB, IIMC. 1 aaao RivanaAi.B arwaaT BAN oiaaa, CAUIFORNIA aa^sa CALAVERA HEIGHTS -VILLAGE W-X-Y SEISMIC RESULTS IY DBA DATE L-11-83 SEISMIC RESULTS JOB NO. nnoi nno Place No. 20 Seismic Velocity ••at Por aaooiMl « 1000 DSL CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 31 23458789 11 12 13 14 15 TOPSOIL CLAY IQNEOUS ROCKS anANiTE 3ABALT SEDIMENTARY ROCKS 3HALE SANDSTONE SILTSTONE CLAYSTONE CONOLOMERATE METAMORPHIC ROCKS SCHIST SLATE K / • : Y Bl 1 • \ A ^ v V \/ A .'' • 1 • \/\/ ' .• I / i \ I.- . i RIPPABLE MAROINAL L NON-RIPPABLE L DBL Ripper Pertormance • Multi or Single Shani^ No. a Ripper • Estimated by Seismic Wave Velocities ' y/Q^ SOUTHERN CALIFORNIA CALAVERA HEIGHTS-VILLAGE W-X-Y 1 Xp^ SOIL 1 TESTING, INC. BY: KAR DATE: 5-03-90 1 Xp^ SOIL 1 TESTING, INC. JOB NUMBER: 9021049 Plate No. 21 DSL CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 Seismic Velocity '••t Pt a.aoM I 1000 D9L Ripper Performance • Mu[t\ or Single Siiank No. 9 Ripper • Estimated by Seismic Wave Velocities SOUTHERN CALIFORNIA SOIL S. TESTING, INC. CALAVERA HEIGHTS-VILLAGEW-X-Y JOB NUMBER: 9021049 DATE: 5-03-90 Plate No. 22 Dl 1N CATERPILLAR PERFORMANCE HANDBOOK Edition 17 October 1986 Seismic Velocity '••t Pmf mmummm i iaoo •0 11 12 13 14 15 TOPSOIL CLAY IGNEOUS ROCKS QRAMTE 3ASALT SEDIMENTARY ROCKS 3 HALE SANDSTONE SLTSTONE CLAYSTONE CONOLOUERATE METAMORPHIC ROCKS SCHIST 3 LATE XZZZZZZZZZZZZZZL \/AX//x//. IZZZZZZZZZZZZL ^ZZZZZZZZZZZ. RIPPABLE MAROMAL MON-fl)PPABLE TZ7Z77 A Dl 1 N Ripper Performance • Multl or Single Shank No. 9 Ripper • Estimated by Seismic Wave Velocities CALAVERA HEIGHTS-VILLAGE W-X-Y BY: KAR DATE: 5-03-90 JOB NUMBER: 9021049 Plate No. 23 | SOUTHERN CALIFORNiA SOIL 3. TESTING, INC. CALAVERA HEIODS VILLflGES W-X-Y, TAMAWCK AND COLLEGE BOULEVARD, CARLSBAD REXXMMENDED GRADING SPECIFICKTIONS - GENERAL PROVISICNS OlIERAL INIENT 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 reconnendations 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. CBSERVKTICW AHJ TESTINS 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 work 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 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 recommendations. (R-9/89) SCS&T 9021049 May 15, 1990 ;>ppendix. Page 2 If, in the opinion of the Geotechnical Engineer, substandard conditions are encountered, such as questionable or unsuitable soil, unacceptable moisture content, inadequate compaction, adverse v^eather, etc.; construction should be stopped until the conditions are remedied or corrected or he shall reconirend rejection of this work. Itests used to determine the degree of compaction should be performed in accordance with the following American Society for Testing and Materials test metJiods: Maximum Density & Optimum Moisture 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. PREPARATIGN OF AREAS TO RECEIVE FILL All vegetation, brush and debris derived from clearing operations shall be renoved, 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 noisture 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 which 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 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 frm 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 when 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 compacted 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 reconitendation will be necessary. All water wells which will be abandoned should be backfilled and capped in accordance to the requirenents 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 whichever 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 detrinental soils are covered in the geotechnical report or Special Prtjvisions. 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 AM) OQMPACnON 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 noisture 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. Compaction equipment should either be specifically designed for soil compaction or of proven reliability. The minimum degree of compaction to be achieved is specified in either the Special Provisions or the recommendations contained in the preliminary geotechnical investigation report. When the structxrral fill material includes rocks, no rocks will be allowed 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 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 compaction tests to estimate the degree of compaction of the fill will be taken by the Geotechnical Engineer or his representative. The iocation 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 compaction has been obtained. Fill slopes shall be conpacted by means of sheepsfoot rollers or other suitable equipnent. 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 trackroUed. 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 conpaction 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 surficially stable. Density tests in the slopes will be nade 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 comnunication from the Geotechnical Engineer or his representative in the form of a daily field report. If the nethod of achieving the required slope compaction 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 CUT SLOPES May 15, 1990 Appendix, Page 6 The Engineering Geologist shall inspect cut slopes excavated in rock or lithified formational material during the grading operations at intervals determmed 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 neasures are necessary. unless otherwise specified in the geotechnical report, no cut slopes shall be excavated higher or steeper than that allov^ 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 Lmns Fill shall not be placed during unfavorable weather conditions. When vork 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) I SCS&T 9021049 May 15, 1990 Appendix, Page 7 RBCXWMENDED OIRDING SPBCIFICATIGNS - SPECIAL PROVISIONS RELKEIVE COMPPCnOUt The minimum degree of conpaction to be obtained in conpacted natural ground, conpacted fill, and compacted backfill shall be at least 90 percent. For street and parking lot si±igrade, the upper six inches should be conpacted to at least 95% relative conpaction. EXPAI6IVE SOUS: Detrimentally expansive soil is defined as clayey soil v^LLCh has an expansion index of 50 or greater when tested in accordance with the Uniform Building Code Standard 29-C. OVERSIZED MKEERIAL: Oversized fill material is generally defined herein as rocks or lumps of soil over 6 inches in diameter. Oversize materials should not be placed in fill unless reconnendations 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. TRANSmON UJIS: Where transitions betveen 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 structxiral backfill. In certain cases that would be addressed in the geotechnical report, special footing reinforcenent or a confcination of special footing reinforcement and undercutting may be required. (R-9/89)