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HomeMy WebLinkAboutCT 04-02; LA COSTA RIDGE NEIGHBORHOODS 2.1 AND 2.2; UPDATE GEOTECHNICAL INVESTIGATION; 2001-08-27I .7 AM ON E UPDATE GEOTECHNICAL INVESTIGATION VILLAGES OF LA COSTA- THE RIDGE CARLSBAD, CALIFORNIA PREPARED FOR REAL ESTATES COLLATERAL MANAGEMENT COMPANY C/O MORROW DEVELOPMENT INCORPORATED CARLSBAD, CALIFORNIA AUGUST 27, 2001 GEOCON INCORPORATED GEOTECHNICAL CONSULTANTS Project No. 06105-12-05 August 27, 2001 Real Estates Collateral Management Company % Morrow Development Incorporated 1903 Wright Place, Suite 180 Carlsbad, Califomia 92008 Attention: Mr. Tim O'Grady Subject: VILLAGES OF LA COSTA—THE RIDGE CARLSBAD, CALIFORNIA UPDATE GEOTECHNICAL INVESTIGATION Gentlemen: In accordance with your authorization (Contract Number 350) and our proposal LG-01238 dated May 4, 2001, we have updated our supplemental geotechnical investigation of the subject site. This work complements previous soil and geologic investigations that have been conducted on the property during the period of 1988 to date. The purpose of this report is to compile all relevant previously generated data along with the results of tiie recent study into a single document presenting our conclusions and recommendations pertaining to the geotechnical aspects of developing the site as proposed. Significant geotechnical issues related to the rippability of the geological units, remedial gradmg of the unsuitable surficial materials and generation of capping materials have been identified in this report and will require consideration during planning and development of the property. However, it is our opinion that the site may be developed as proposed, provided the recommendations of this report are followed. If you should have any questions regarding this report, or if we may be of fiirther service, please do not hesitate to contact the undersigned at your convenience. Very truly yours, ICON INJ RCE 2252 AS:DFL:dlj (6) Addressee (3) Hunsaker & Associates Attention: Mr. Kurt Steimagle All Sadr •TEG 1778 6960 Flanders Drive • San Diego, California 92121-2974 • Telephone (858) 558-6900 • Fax (858) 558-6159 TABLE OF CONTENTS 1. PURPOSE AND SCOPE 1 2. SITE AND PROJECT DESCRIPTION 2 3. SOIL AND GEOLOGIC CONDITIONS 3 3.1 Stratigraphy 3 3.2 Santiago Peak Volcanics (Jsp) 3 3.3 Undifferentiated Metamorphic Rocks (Jm) 3 3.4 San Marcos Gabbro (Ksm) 3 3.5 Escondido Creek Granodiorite (Ke) 4 3.6 Alluvium (Qal) 4 3.7 Colluvium (Qc) 4 3.8 Topsoil (Unmapped) 4 3.9 Fill Material (Qudf) l..!*Z!!!!!Z!!ZZ!!!Z!"Z!"!!!Z!!!"!5 4. GROUNDWATER 5 5. GEOLOGIC STRUCTURE 5 6. GEOLOGIC HAZARDS 6 6.1 Faulting and Seismicity 6 6.2 Liquefaction 7 7. CONCLUSIONS AND RECOMMENDATIONS 8 7.1 General g 7.2 Geologic Hazards g 7.3 Groundwater g 7.4 Soil and Excavation Characteristics 9 7.5 Slope Stability ZZZZZZZ"ZZZl9 7.6 Grading n 7.7 Subdrains I3 7.8 Bulking and Shrinkage Factors I3 7.9 Foundation Recommendations 14 7.10 Retaining Walls and Lateral Loads 17 7.11 Slope Maintenance 1 g 7.12 Drainage I9 7.13 Plan Review I9 LIMITATIONS AND UNIFORMITY OF CONDITIONS MAPS AND ILLUSTRATIONS Figure 1, Vicinity Map Figures 2-5, Geologic Maps (Map Pocket) Figure 6, Fill Slope Stability Analysis Figure 7, Surficial Slope Stability Analysis Figure 8, Canyon Subdrain Detail TABLE OF CONTENTS (Continued) APPENDIX A FIELD INVESTIGATION Figures A-1 - A-11, Logs of Trenches Figures A-12 - A-28, Logs of Air-track Borings APPENDIX B LABORATORY TESTING Table B-I, Summary of Laboratory Expansion Index Test Results APPENDIX C SELECTED BORING AND TRENCH LOGS AND LABORATORY TESTING FROM NINYO & MOORE (1991) APPENDIX D RECOMMENDED GRADING SPECIFICATIONS UPDATE GEOTECHNICAL INVESTIGATION 1. PURPOSE AND SCOPE This report presents the consoUdated findings of current and previous geotechnical investigations for The Ridge of the Villages of La Costa in Carlsbad, Califomia (see Vicinity Map, Figure 1). This report is intended to present recommendations relative to geotechnical aspects of site development, including remedial grading, estimated rock rippability, slope stability, subsurface drainage, estimated bulking and shrmkage factors, and recommended grading specifications and preliminary foundation design criteria. It should be noted that the site was previously known as Rancheros. The scope of the investigation included a review of the following: 1. Preliminary Geotechnical Investigation, Villages of La Costa—The Oaks and Ridge, Carlsbad, California, prepared by Geocon Incorporated, dated January 10, 2000 (Project No. 06105-12-01). 2. Update Geotechnical Evaluation, Rancheros Subdivision, Carlsbad, Califomia, prepared by Ninyo and Moore, dated December 30, 1991 (Project No. 102219-01) 3. Geologic Maps of the Northwestern Part of San Diego County, California, DMG Open File Report 96-02. 4. Batholith and Associated Rocks of Corona, Elsinore and San Luis Rey Quadrangles, Southern California, Geological Society of America Memoir 29, 1948. 5. On the Manner of Deposition of the Eocene Strata in Northern San Diego County, San Diego Association of Geologists Guidebook, 1985. 6. Stratigraphy and Petrography of the Santiago Peak Volcanics East of Rancho Santa Fe, Califomia, unpublished M.S. thesis, by M. A. Adams, San Diego State University, 1979. 7. Geology and Mineral Resources of San Diego County, California, DMG County Report 3, 1963. 8. Unpublished reports, aerial photographs and maps on file with our firm. The scope of the most recent field investigation (January 2000) consisted of a site geologic reconnaiss£ince and the drilling of 16 hydraulic air-track borings and excavation of 11 exploratory trenches. Laboratory tests were performed on selected soil samples obtained at various depths in the exploratory excavations to evaluate pertinent physical properties. Details of the field exploration and laboratory testing programs are presented in Appendices A andB, respectively. Selected logs of Project No. 06105-12-05 - 1 - August 27,2001 exploratory excavations and seismic refi-action data extracted from the Ninyo and Moore report (Reference No. 2) are presented in Appendix C. The recommendations presented herein are based on analyses of the data obtained from our recent and previous exploratory excavations, laboratory tests and our experience with similar soil and geologic conditions. The base maps used for this study consisted of conceptual grading plans, 1 inch equals 100 feet (1" = 100') scale, entitled Mjr^^e/- Tentative Tract Map CT98-04/HDP 99-02, Villages of La Costa, city of Carlsbad Califomia, prepared by Hunsaker & Associates, undated (see Figures 2 through 5, map pocket). The results of the field investigation are compiled on Figures 2 through 5. 2. SITE AND PROJECT DESCRIPTION The Ridge is located southwest of El Fuerte Street and Alga Road intersection and northwest of San Marcos Creek. The ridge encompasses approximately 550 acres and consists of a single, roughly dome-shaped, mountain and a northeast-southwest- trending ridge separated by drainage canyons. Elevations range fi-om approximately 700 feet Mean Sea Level (MSL) at the knob at the northwest portion of the site to approximately 250 feet MSL within the canyon at the southem edge of the site. Lot 2.01 located east of Corintia Street, within the eastem portion of the site, is designated for multi- family residential site and is excluded from this report. A separate geotechnical report has been issued for this lot. The report is entitled Preliminary Geotechnical Investigation, Villages of La Costa, Multi-Family Residential Site, Carlsbad, California, prepared by Geocon Incorporated, dated July 12, 2001. Vegetation typically consists of thick chaparral and grasses through a majority of the site. The lower drainages feeding San Marcos Creek, however, have mature to old-age native stands of Valley Oak and Sycamore. Running water was observed in San Marcos Creek. Existing improvements on The Ridge include a water tank located at the knob at the northem portion of the site. A buried water line is aligned westward from the water tank to El Fuerte Street and to the north to Alga Road. A review of the 100-scale conceptual grading plans for The Ridge subdivision, prepared by Hunsaker & Associates, indicates that the site will be graded to create large sheet-graded pads. The sheet-graded pads within the project will eventually be regraded to construct residential units with associated roads and improvements. The grading will result in maximum fill and cut of approximately 35 and 40 feet, respectively. The cut and fill slopes planned for the project will consist of maximum heights of 40 and 65 feet, respectively, with 2:1 (horizontahvertical) inclination. Project No. 06105-12-05 - 2 - August 27, 2001 3. SOIL AND GEOLOGIC CONDITIONS 3.1 Stratigraphy Four surficial soil types and three geologic units were encountered during our investigation. The surficial deposits include undocumented fills, topsoils, colluvium and alluvium. Geologic formations include the Jurassic-aged Santiago Peak Volcanics, Jurassic metamorphic rocks, Cretaceous-aged Escondido Granodiorite and San Marcos Gabbro. Each of the soil types and geologic units encountered are described below, and their approximate mapped extent is depicted on Figures 2 through 5, Geologic Maps (map pocket). 3.2 Santiago Peak Volcanics (Jsp) The Jurassic-aged Santiago Peak Volcanics, with the exception of the north central portion of the site, comprise the majority of the underlying bedrock. These rocks were deposited as an alternating secession of volcanic flows, tuffs and breccias and typically have an andesite or dacite composition. Subsequently this sequence of rocks was folded, faulted and weakly metamorphosed (see reference by Adams, 1979). Where observed in test excavations, this unit is highly fractured and faulted along northwest-to-southeast zones. Closely spaced parallel fractures and joints form "sheeted" zones containing colorfiil alteration and/or oxidation minerals such as lunonite and hematite. Even though the majority of the Santiago Peak Volcanics appears to be highly fractured and altered, the zones typically have steeply dipping, tight clay-filled fractures. In addition, some of the highly fractured and altered portions of this unit excavate to a gravelly-clayey sand and very sandy clay. Discussion of theses areas as sources of suitable capping fines is presented in the concluding sections of this report. In general, however, hardrock areas will require special handling and pre-blasting considerations as presented in the concluding sections of this report. 3.3 Undifferentiated Metamorphic Rocks (Jm) An elongate body of very weathered, fractured, Jurassic-aged metasedimentary to metavolcanic rocks was encountered in the northern portion of the project (Figure 4 near Trench T-17). This unit excavates to a clayey, gravelly sand and a sandy gravel and may also provide suitable capping material fines. The unit is elongated north-south and approximately follows the contact between Santiago Peak Volcanics on the west and Escondido Creek Granodiorite on the east. It is also intruded by very fractured dikes of granodiorite. 3.4 San Marcos Gabbro (Ksm) The Cretaceous-aged San Marcos Gabbro was encountered on the project as an elliptical-shaped body approximately 1400 feet long and 700 feet wide. This unit typically exhibits a very weathered, fractured texture and is excavatable with moderate effort to depths ranging between 15 and 25 feet Project No. 06105-12-05 - 3 - August 27,2001 (see Trench Nos. T-21, T-22, T-23 and T-24). It excavates to a clayey sand and sandy fine gravel, and could provide a substantial source of capping material. 3.5 Escondido Creek Granodiorite (Ke) In the published literature this unit is described as a "leucogranodiorite" because ofthe overall light color, but averages of composition are typically granodiorite (Larsen, 1948). This Cretaceous-aged batholithic rock intrudes Santiago Peak Volcanics. Outcrops and exploratory trenches expose light brown to olive, very siliceous, blocky and very strong granitic rock, with little or no weathering. Although rippable m highly fractured areas, this unit will excavate to substantial amounts of oversize rock, or will require special handling or pre-blasting in hardrock areas, as discussed in the concluding sections of this report. 3.6 Alluvium (Qal) The alluvial deposits are typically composed of loose, porous, clay-sand mixtures with boulders that have accumulated along canyon bottoms. The average observed thickness was approximately 5 to 6 feet. These sediments are generally poorly consolidated and susceptible to settlement when subjected to an increase in vertical loads as might result from the placement of fill or structures. Hence, development within areas containing alluvial deposits will require remedial grading as discussed in the conclusions and recommendations portions of this report. 3.7 Colluvium (Qc) Colluvial soils occur along the canyon side-slopes, low areas, the base of natural slopes. These deposits are often indistinguishable from alluvium and thick topsoil deposits, therefore, only the thicker, or potentially thicker areas have been mapped separately on the Geologic Maps. In general, these deposits consist of poorly consolidated sandy clays to clayey sands and are potentially compressible. Development within areas underlain by colluvium will require remedial grading as recommended in the concluding sections of this report. 3.8 Topsoil (Unmapped) Topsoils of irregular thicknesses ranging from 1 to 2 feet blanket die majority ofthe site. The topsoils are characterized by dark brown to reddish-brown gravelly silty sands to sandy clays. These soils are both moderately to highly expansive, as well as potentially compressible. Recommendations with respect to the treatment of topsoils have been included under the conclusions and recommendations section of this report. Project No. 06105-12-05 - 4 - August 27,2001 3.9 Fill Material (Qudf) Fill materials encountered at the site are associated with the water tank, the water lines and the access roads. In addition, end dumps and trash were also observed at various locations, mostly near the adjacent streets. These materials are considered unsuitable for receiving additional fill or structures, and should be remediated if not removed by grading. 4. GROUNDWATER No seepage or groundwater table was detected within exploratory borings or trenches in proposed cuts. Due to the highly fractured nature of the underlying bedrock formations, the path of groundwater migration is impossible to predict. In addition, subsequent grading planned for The Ridge will change the land form and possibly alter future subsurface flow. During development of The Ridge, surface water control devices will be installed. These would include typical storm drain systems to collect water originating from the residential lots and streets and diverting it to controlled drainage systems. Brow ditches installed in slopes will also collect surface water and direct it to flow to controlled devices. At the toe of cut slopes located within materials where seepage is anticipated, cut-off drains will be installed to intercept groundwater seepage. During grading, fill slopes identified as potential seepage sources may have backdrains installed, and within canyon fills, subdrains will be installed prior to placing fill to collect and properly discharge groundwater migrating through the fill. San Marcos Creek is a perennial stream and surface water flow was noted durmg the field investigation. Observed groundwater levels in the surroundmg drainage area ranged between 3 and 5 feet below existing ground surface. 5. GEOLOGIC STRUCTURE Fracturing within the Jurassic-age Santiago Peak Volcanics typically exhibit northwest-to-southeast linear trends, with associated less-intense northeast-to-southwest cross fracturing. A moderately developed "trellis" drainage pattern is imposed on many, small tributary drainages by the northwest-to-southeast trends. Typically, joints have steep (greater than 45 degrees) dips, but occasional low-angle dips of approximately 5 degrees have been noted. Project No. 06105-12-05 - 5 - August 27,2001 GEOLOGIC HAZARDS 6.1 Faulting and Seismicity It is our opinion, based on the site reconnaissance, evidence obtained in the exploratory excavations and a review of published and unpublished maps and reports, that the site is not located on any known active fault trace. The nearest known active faults are the Rose Canyon Fault and the Newport-Inglewood (offshore) located approximately 8 and 13 miles, respectively, to the west and Elsinore Fault Zone, which lies approximately 23 miles to the northeast. Maximum Credible and Maximum Probable Seismic events of Magnitude 6.9 and Magnitude 5.7, respectively, are postulated for the Rose Canyon Fault. The estimated Maximum Credible and Maxunum Probable Peak site acceleration are 0.28 g and 0.13g, respectively. Seismic parameters for the other regional faults capable of generating ground acceleration at the site are summarized on Table 6.1. TABLE 6.1 DETERMINISTIC SITE PARAMETERS FOR SELECTED FAULTS* Fault Distance from Site (miles) Maximum Credible Maximum Probable Fault Distance from Site (miles) Earthquake (Mag.) Peak Acceleration (g) Earthquake (Mag.) Site Acceleration (g) Rose Canyon 8 6.9 0.28 5.7 0.13 Newport-Inglewood (offshore) 13 6.9 0.20 5.8 0.10 Elsinore-Julian 23 7.1 0.13 6.4 0.08 Elsinore-Temecula 23 6.8 0.11 6.3 0.07 Coronado Bank 23 7.4 0.16 6.3 0.07 Elsinore-Glen Ivy 38 6.8 0.06 6.3 0.04 Palos Verdes 43 7.1 0.06 6.2 0.03 San Jacinto-Anza 46 7.2 0.06 6.9 0.05 *EQ Fault Computer Program, Blake, 1997. It is our opinion that the site could be subjected to moderate to severe ground shaking in the event of a major earthquake along any of the above-mentioned faults, however, the seismic risk at the site is not considered to be significantly different than that of the surrounding developments of similar geologic setting in Oceanside area. Project No. 06105-12-05 August 27,2001 6.2 Liquefaction The potential for liquefaction during a strong earthquake is limited to cohesionless soils which are in a relatively loose, unconsolidated condition and located below the groundwater level. Due to the dense nature of the formational units, the removal and recompaction of the surficial soils and the absence of a permanent groundwater table, the potential for seismically included soil liquefaction occurring at the site is considered to be very low. I I Project No. 06105-12-05 -7- August 27, 2001 7. CONCLUSIONS AND RECOMMENDATIONS 7.1 General 7.1.1 No soil or geologic conditions were encountered during the mvestigation performed by Geocon Incorporated or those of the previous studies which, in our opinion, would preclude the development of the property as presently planned, provided the recommendations of this study are followed. 7.1.2 The surficial soils consisting of alluvium, fill, topsoils and colluvium are not considered suitable for the support of fill or structural loads in their present condition and will require remedial grading. 7.1.3 The presence of oversize boulders and marginally rippable to nonrippable volcanic and granitic rocks will require special consideration during site development as recommended hereinafter. 7.1.4 Due to the expected presence of a large volume of rock, a selective grading operation with possible stockpiling of the soil material and rippable rock is recommended. Details of the recommended selective grading operation are presented under Section 7.6 Grading. 7.2 Geologic Hazards 7.2.1 It is our opinion, based on the site recormaissance, evidence obtained in the exploratory excavations and a review of published geologic maps and reports, that the site is not located on any known active fault trace. 7.2.2 It is our opinion that the site could be subjected to moderate to severe ground shaking in the event of a major earthquake along any of the active faults in the San Diego County area; however, the seismic risk at the site is not considered to be any greater than that of surrounding developments in the City of Carlsbad area. 7.3 Groundwater 7.3.1 The geologic units encountered on the site have permeability characteristics and/or fracture systems that could be susceptible under certain conditions to water seepage. Inasmuch as no springs, seeps, or groundwater occurrences were encountered within the formational soil units, it is our opinion that the seepage potential for the geologic units is relatively low. It is recommended, however, that periodic observations be made by the soil engineer or Project No. 06105-12-05 - 8 - August 27,2001 engineering geologist during grading and/or construction for the presence of groundwater. The recommendations that follow provide for the removal of colluvial, alluvial and undocumented fill soils and the placement of a "canyon" subdrain within the bottom of the removal areas to reduce the potential for groundwater buildup within the canyon fills. 7.4 Soil and Excavation Characteristics 7.4.1 The soil conditions encountered vary from low-expansive sands, generated from the decomposed bedrock, to highly expansive soil of colluvium and some of the other surficial soils. 7.4.2 In our opinion, the existing topsoils and alluvial/colluvial deposits can be excavated with light to moderate effort with conventional heavy-duty grading equipment. It is estimated that the proposed grading will encounter rippable rock to depths on the order of 10 to 15 feet below existing ground surface. Surface blasting will be required where highly resistant rocks are exposed. It is likely, however, that excavations greater than 15 feet within the major cut areas will encounter marginal to nonrippable rock conditions with a high percentage of "floater" boulders and bedrock "knobs" that will require blasting. Nonrippable "core stones" may also be encountered during excavation in otherwise rippable areas. Oversize rocks should be placed in accordance with the Recommended Grading Specifications presented in Appendix D. In addition, we recommend that consideration be given to placing the boulders in the open areas for landscaping purposes, or placement within excavations selectively mined for capping materials. 7.5 Slope Stability 7.5.1 Utilizing average drained shear strength parameters based on laboratory tests and experience with similar soil types in nearby areas, a slope stability analysis indicates that the proposed 2.0 to 1.0 (horizontal to vertical) fill slopes constructed of granular material will have calculated factors of safety in excess of 1.5 under static conditions for both deep- seated and shallow sloughing failures up to the design heights of 65 feet. Slope stability calculations and surficial stability calculations are presented on Figures 6 and 7, respectively. 7.5.2 All fill slopes should be constructed such that the materials, within a zone measured horizontally back from the face of slope for a distance equal to the height of slope, are generally comprised of granular soils and/or soil/rock fills with minimum equivalent strength parameters of 0' =32 degrees and C' =300 psf. However, the outer 15 feet of fill slopes will be restricted to materials composed of properly compacted granular "soil" fill to Project No. 06105-12-05 - 9 - August 27,2001 reduce the potential for surface sloughing. All fill slopes should be compacted by back- rolling at vertical intervals not to exceed 4 feet and should be track-walked (for slopes 2:1 or flatter) at the completion of each slope such that the fill soils are uniformly compacted to at least 90 percent relative compaction. As an altemative, fill slopes should be overbuilt a minimum of 5 feet horizontally and cut back to design finish grade. 7.5.3 Cut slopes excavated in the metavolcanic and plutonic rocks do not lend themselves to conventional stability analyses. However, the results of our field investigation, our experience in the general area and the examination of the existing slopes adjacent to the property mdicate that the proposed 2.0 to 1.0 (horizontal to vertical) cut slopes should be stable with respect to deep-seated failure and surficial sloughage up to the proposed maximum height of 50 feet. 7.5.4 Where cuts exceed the maximum depth of the weathered portion of the metavolcanic and plutonic rocks, heavy blastmg will be requhed to break the fresh, very hard rock. Overblasting of cut slopes should not be permitted. Loose rock and blasting debris should be removed from the faces of finish graded cut slopes. No loose rock fragments greater than 6 inches Ln maximum dimension should be left on the slope surface. Tops of cut slopes should be cleared of loose boulders and should be "rounded" within the exposed topsoil horizon. 7.5.5 In our opinion, the use of terrace drains on cut or fill slopes exceeding 30 feet m height is not necessary to maintain gross stability of the slopes. However, the proper installation and maintenance of terrace drains should measurably reduce surficial slope erosion, particularly fill slopes. If used, we recommend that terrace drains be constructed at a drainage gradient of at least 5 percent. In addition, the need to properly maintain the drains is important. Drains that are not periodically cleaned of vegetation and debris could result in significant slope distress and erosion. 7.5.6 It is recommended that all cut slopes be observed during grading by an engineering geologist to verify that soil and geologic conditions do not differ significantly from those anticipated. If adverse conditions are encountered, recommendations for mitigation can be presented at that time. 7.5.7 All slopes should be planted, drained and properly maintained to reduce erosion. Project No. 06105-12-05 - 10 - August 27,2001 7.6 Grading 7.6.1 Development of the site as proposed will generate a relatively large volume of oversize rock as well as shot rock. Earthwork considerations which need to be addressed within the development schedule are summarized as follows: • Grading and blasting operations should be designed to generate a sufficient quantity of granular material for use as low expansive capping material. Where this is not possible, rock crushing may be required. • Consideration should be given to stockpiling select materials to be utilized for capping. • Oversize rock should be placed in deeper fill areas in accordance with the Recommended Grading Specifications presented in Appendix D. • Appropriate remediation and/or backfilling of any old abandoned mines or prospect pits should be implemented during site development. 7.6.2 All grading should be performed in accordance with the attached Recommended Grading Specifications (Appendix D). Where the recommendations of this section conflict with Appendix D, the recommendations of this section take precedence. All earthwork should be observed and all fills tested for proper compaction by Geocon Incorporated. 7.6.3 Prior to commencing grading, a preconstruction conference should be held at the site with the owner or developer, grading contractor, civil engineer and geotechnical engineer in attendance. Special soil handling and/or the grading plans can be discussed at that tune. 7.6.4 Grading operations on the site should be scheduled so as to place the rock and expansive soils in the deeper fills and to "cap" the pads and fill slopes with granular soils with low expansion potential (Expansion Index of 50 or less, per UBC Table 18-I-B). 7.6.5 It is anticipated that, during the excavation of the major cut areas, a moderate quantity of surface and "floater" rocks in excess of 4 feet in size will be generated. In our opinion, these rocks are suitable for placement in the fill areas, provided the placement is accomplished in accordance with the recommendations presented in Appendix D. In addition, utilization of as many boulders as practical for landscape purposes should be considered. Excavation of the deeper bedrock units should produce a relatively lower quantity of large "floater" rocks, if an efficient blasting program is implemented. The proposed blasting program should also be planned to assist in the generation of "fines". If possible, the grading operation should attempt to reserve sufficient "soil" fill for use in capping the "rock" fills as discussed in Appendix D and to replace trench excavation material which is considered too rocky to be used as trench backfill. ProjectNo. 06105-12-05 - 11 - August27,2001 7.6.6 All potentially compressible topsoils and alluvium, and colluvium, not removed by planned grading should be removed to firm natural ground in areas of proposed development and properly compacted prior to placing additional fill. Where the thickness is less than 3 feet on sloping ground, it is anticipated that nonnal benching procedures for sloping ground surfaces will remove the unsuitable topsoils. Thicknesses greater than 3 feet or areas of numerous surface boulders will require complete removal prior to performing normal benching procedures. 7.6.7 The site should then be brought to final subgrade elevations with structural fill compacted in layers, in general, soils present on site are suitable for re-use as fill if free from vegetation, debris and other deleterious material. Layers of fill should be no thicker than will allow for adequate bounding and compaction. Includmg backfill and scarified ground surfaces, should be compacted to at least 90 percent of maximum dry density at near optimum moisture content, as determined in accordance with ASTM test procedure D 1557-91. Fill materials below optimum moisture content may be unacceptable and require additional moisture conditioning prior to placing additional fill. The project soils engineer/engineering geologist will determine actual moisture conditioning requirements during grading and as a function of soil type. 7.6.8 Consideration should be given to undercutting and replacing with compacted "soil fill" (no rocks greater than 12 inches in maximum dimension) any proposed cut areas located on the hard bedrock outcrops. The depth of undercutting should be at least 3 feet below the ultimate pad finish grade and 1 foot below the deepest utility lines, or, altematively, to sufficient depth such that underground utilities can be constructed without-the need for additional blasting or heavy ripping after the mass grading has been accomplished. Within rock cut areas where only landscaping is proposed, the project landscape architect should be consulted to determine an appropriate depth of undercut, if any. To reduce the potential for differential settlement, it is recommended that the cut portions of the cut/fill transition building pads be undercut at least 3 feet and replaced with properly compacted fill soils. The undercut should extend from the back of the pad to the street and be graded at a gradient of at least 1 percent toward the street. 7.6.9 Consideration should be given to capping street areas with a minimum of 3 feet of subgrade soils consisting of granular soils possessing relatively high R-Value characteristics. This will serve to reduce recommended pavement design sections. Project No. 06105-12-05 - 12 - August 27,2001 7.7 Subdrains 7.7.1 Subdrains should be installed in the canyons to be filled. A cross-section of the subdrain configuration is presented on Figure 8. The lower 20 feet of the subdrain installation should consist of nonperforated pipe with a concrete cutoff wall constructed immediately below the junction of the perforated pipe with the nonperforated pipe. The cutoff wall should extend at least 6 inches below the sides and bottom of the subdrain trench and 6 inches above the top of the pipe. 7.7.2 In order to maintam a drainage gradient within the canyon subdrain system, it may be necessary to extend the nonperforated outiet pipe beyond the limits of planned grading operations. As an alternative design, a properly compacted fill may be placed within the lower canyon bottom until the minimum drainage gradient is achieved. Two subdrains would then be installed along the fill/natural ground contacts. Where the natural slope gradient exceeds 5 percent, the perforated pipe may be deleted from the subdram system. 7.7.3 After installation of the subdrain, the project civil engineer should survey its location and prepare "as-built" plans of the subdrain location. The project civil engmeer should verify the proper outiet for the canyon subdrains and the contractor should ensure that the drain system outlet is free of obstructions. The recommended locations of the canyon subdrains will be finalized during a review of the final site grading and improvement plans. 7.8 Bulking and Shrinkage Factors 7.8.1 Estimates of embankment bulking and shrinkage factors are generally based on comparing laboratory compaction tests with the density of the material in its natural state as encountered in the chunk samples. It should be emphasized that variations in natural soil density, as well as in compacted fill density, render shrinkage value estimates very approximate. As an example, the compaction of fill soils can vary from 90% to approximately 100% and, hence, a 10% variation in shrinkage is possible. Based on the extent of work performed to date, the following shrinkage factors are recommended for evaluating eartliwork quantities. TABLE 7.8 SHRINKAGE/BULK FACTOR Soil Unit Shrink/Bulk Factor Alluvium, Topsoils, Fill, Colluvium 5 to 10 percent shrink Weathered Rippable Bedrock 10 to 15 percent bulk Nonrippable Bedrock 20 to 25 percent bulk ProjectNo. 06105-12-05 - 13 - August 27,2001 7.9 Foundation Recommendations 7.9.1 The following foundation recommendations are for one-and/or two-story residential structures and are based upon the assumption that the soil conditions within 4 feet of finish pad subgrade consist of granular "low" expansive soil (Expansion Index less than 50). The recommendations are separated into categories dependent upon the depth and geometry of fill underlying a particular building pad and/or lot. Final foundation design recommendations for each building will be presented in the final compaction report after the grading for the mdividual building pads has been completed. 7.9.2 Foundations for either Category I, II, or III, as described in Table 7.9.1, may be designed for an allowable soil bearing pressure of 2,000 pounds per square foot (psf) (dead plus live load). This bearing pressure may be increased by one-third for transient loads such as wind or seismic forces. 7.9.3 The use of isolated footings that are located beyond the perimeter of the building and support structural elements connected to the building is not recommended for Category III. Where this condition cannot be avoided, the isolated footings should be connected to the building foundation system with grade beams. 7.9.4 For Foundation Category III, the structural slab design should consider using ulterior stiffening beams and connecting isolated footings and/or increasing the slab thickness. In addition, consideration should be given to connecting patio slabs, which exceed 5 feet in width, to the building foundation to reduce the potential for future separation to occur. 7.9.5 No special subgrade preparation is deemed necessary prior to placing concrete, however, the exposed foundation and slab subgrade soils should be sprinkled, as necessary, to maintain a moist soil condition as would be expected in any such concrete placement. However, where drying of subgrade soils has occurred, reconditioning of surficial soils will be required. This recommendation applies to foundations as well as exterior concrete flatwork. Project No. 06105-12-05 - 14 - August 27, 2001 TABLE 7.9.1 FOUNDATION RECOMMENDATIONS BY CATEGORY Foundation Category Minimum Footing Depth (inches) Continuous Footing Reinforcement Interior Slab Reinforcement I 12 One No. 4 bar top and bottom 6 x 6 -10/10 welded wire mesh at slab mid-point n 18 Two No. 4 bars top and bottom No. 3 bars at 24 inches on center, both directions III 24 Two No. 5 bars top and bottom No. 3 bars at 18 inches on center, both directions CATEGORY CRITERIA Category!: Maximum fill thickness is less than 20 feet and Expansion Index is less than or equal to 50. Category n: Maximum fill thickness is less than 50 feet and Expansion Index is less than or equal to 90, or variation in fill thickness is between 10 feet and 20 feet. Category HI: Fill thickness exceeds 50 feet, or variation in fill thickness exceeds 20 feet, or Expansion Index exceeds 90, but is less than 130. Notes: 1. All footings should have a minimum width of 12 inches. 2. Footing depth is measured from lowest adjacent subgrade (including topsoil, if planned). These depths apply to both exterior and interior footings.. 3. All interior living area concrete slabs should be at least 4 inches thick for Categories I and II and 5 inches thick for Category III. This apphes to both building and garage slabs-on-grade. 4. All interior concrete slabs should be underlain by at least 4 inches (3 inches for 5-mch-thick slab) of clean sand or crushed rock. 5. All slabs expected to receive moisture sensitive floor coverings or used to store moisture sensitive materials should be underlain by a vapor barrier covered wiSi at least 2 inches of the_clean sand recommended in No. 4 above. 7.9.6 Where buildings or other unprovements are planned near the top of a slope steeper than 3:1 (horizontahvertical), special foundations and/or design considerations are recommended due to the tendency for lateral soil movement to occur. • For fill slopes less than 20 feet high, building and wall footings should be deepened such that the bottom outside edge of the footing is at least 7 feet horizontally from the face of the slope. • Where the height of the fill slope exceeds 20 feet, the mmimum horizontal distance should be increased to H/3 (where H equals the vertical distance from the top of the slope to the toe) but need not exceed 40 feet. For composite (fill over cut) slopes, H equals the vertical distance from the top of the slope to the bottom of the fill portion of the slope. An acceptable altemative to deepening the footings would be the use of a post-tensioned slab and foundation system or increased footing and slab reinforcement. Specific design parameters or recommendations for either of these altematives can be provided once the building location and fill slope geometry have been determined. ProjectNo. 06105-12-05 -15-August 27, 2001 7.9.7 • For cut slopes in dense formational materials, or fill slopes inclined at 3:1 (hori- zontahvertical) or flatter, the bottom outside edge of building and wall footings should be at least 7 feet horizontally from the face of the slope, regardless of slope height. • Swimming pools located within 7 feet of the top of cut or fill slopes are not recommended. Where such a condition caimot be avoided, it is recommended that the portion of the swimming pool wall withm 7 feet of the slope face be designed assummg that fhe adjacent soil provides no lateral support. This recommendation applies to fill slopes up to 30 feet in height, and cut slopes regardless of height. For swimming pools located near the top of fill slopes greater than 30 feet in height, additional recommendations may be required and Geocon Incorporated should be contacted for a review of specific site conditions. • Although other improvements that are relatively rigid or brittle, such as concrete flatwork or masonry walls, may experience some distress if located near the top of a slope, it is generally not economical to mitigate this potential. It may be possible, however, to incorporate design measures that would permit some lateral soil movement without causing extensive distress. Geocon Incorporated should be consulted for specific recommendations. As an altemative to the foundation recommendations for each category, consideration should be given to the use of post-tensioned concrete slab and foundation systems for the support of the proposed structures. The post-tensioned systems should be designed by a structural engineer experienced in post-tensioned slab design and design criteria of the Post-Tensioning Institute (UBC Section 1816). Although this procedure was developed for expansive soils, it is understood that it can also be used to reduce the potential for foundation distress due to differential fill settlement. The post-tensioned design should mcorporate the geotechnical parameters presented on the following table entitled Post- Tensioned Foundation System Design Parameters for the particular Foundation Category designated. TABLE 7.9.2 POST-TENSIONED FOUNDATION SYSTEM DESIGN PARAMETERS Post-Tensioning Institute (PTI) Design Parameters Foundation Cateeorv Post-Tensioning Institute (PTI) Design Parameters I II m 1. Thomthwaite Index -20 -20 -20 2. Clay Type - Montmorillonite Yes Yes Yes 3. Clay Portion (Maximum) 30% 50% 70% 4. Depth to Constant Soil Suction 7.0 ft. 7.0 ft. 7.0 ft. 5. Soil Suction 3.6 fl. 3.6 ft. 3.6 ft. 6. Moisture Velocity 0.7 in./mo. 0.7 in./mo. 0.7 in./mo. 7. Edge Lift Moisture Variation Distance 2.6 ft. 2.6 ft. 2.6 ft. 8. Edge Lift 0.41 in. 0.78 in. L15 in. 9. Center Lift Moisture Variation Distance 5.3 ft. 5.3 ft. 5.3 ft. 10. Center Lift 2.12 in. 3.21 in. 4.74 in. ProjectNo. 06105-12-05 16-August27,2001 7.9.8 UBC Section 1816 uses interior stiffener beams in its structural design procedures. If the structural engineer proposes a post-tensioned foundation design method other than UBC Section 1816, it is recommended that interior stiffener beams be used for Foundation Categories II and III. The depth of the perimeter foundation should be at least 12 inches for Foundation Category I. Where the Expansion Index for a particular building pad exceeds 50 but is less than 91, the perraieter footing depth should be at least 18 inches; and where it exceeds 90 but is less than 130, the perimeter footing depth should be at least 24 inches. Geocon Incorporated should be consulted to provide additional design parameters as required by the structural engineer. 7.9.9 The recommendations of this report are intended to reduce the potential for cracking of slabs due to expansive soils (if present), differential settlement of deep fills or fills of varying thicknesses. However, even with the incorporation of the recommendations presented herein, foundations, stucco walls, and slabs-on-grade placed on such conditions may still exhibit some cracking due to soil movement and/or shrinkage. The occurrence of concrete shrinkage cracks is independent of the supportmg soil characteristics. Their occurrence may be reduced and/or controlled by limitmg the slump of the concrete, proper concrete placement and curing, and by the placement df crack control joints at periodic intervals, in particular, where re-entry slab comers occur. 7.10 Retaining Walls and Lateral Loads 7.10.1 Retaining walls not restrained at the top and having a level backfill surface should be designed for an active soil pressure equivalent to the pressure exerted by a fluid density of 30 pounds per cubic foot (pcf). Where the backfill will be inclined at no steeper than 2.0 to 1.0, an active soil pressure of 40 pcf is recommended. These soil pressures assume that the backfill materials within an area bounded by the wall and a 1:1 plane extending upward from the base of the wall possess an Expansion Index of less than 50. For those lots with finish grade soils having an Expansion Index greater than 50 and/or where backfill materials do not conform to the above criteria, Geocon Incorporated should be consulted for additional recommendations. 7.10.2 Unrestrained walls are those that are allowed to rotate more than 0.00 IH at the top of the wall. Where walls are restrained from movement at the top, an additional uniform pressure of 7H psf (where H equals the height of the retaining wall portion of the wall in feet) should be added to the above active soil pressure. 7.10.3 All retaining walls should be provided with a drainage system adequate to prevent the buildup of hydrostatic forces and should be waterproofed as required by the project Proj ect No. 06105-12-05 - 17 - August 27,2001 architect. The use of drainage openings through the base of the wall (weep holes, etc.) is not recommended where the seepage could be a nuisance or otherwise adversely impact the property adjacent to the base of the wall. The above recommendations assume a properly compacted granular (Expansion Index less than 50) backfill material with no hydrostatic forces or imposed surcharge load. If conditions different than those described are anticipated, or if specific drainage details are desired, Geocon Incorporated should be contacted for additional recommendations. 7.10.4 In general, wall foundations having a minimum depth and width of one foot may be designed for an allowable soil bearing pressure of 2,000 psf, provided the soil within 3 feet below the base of the wall has an Expansion Index of less than 90. The proximity of the foundation to the top of a slope steeper than 3:1 could impact the allowable soil bearing pressure. Therefore, Geocon Incorporated should be consulted where such a condition is anticipated. The location of wall footings, however, should comply with the recommendations presented in Section 7.9.6. 7.10.5 For resistance to lateral loads, an allowable passive earth pressure equivalent to a fluid density of 300 pcf is recommended for footings or shear keys poured neat agauist properly compacted granular fill soils or undisturbed natural soils. The allowable passive pressure assumes a horizontal surface extendmg at least 5 feet or three tunes the surface generating the passive pressure, whichever is greater. The upper 12 inches of material not protected by floor slabs or pavement should not be mcluded in the design for lateral resistance. An allowable friction coefficient of 0.4 may be used for resistance to sliding between soil and concrete. This friction coefficient may be combined with the allowable passive earth pressure when determining resistance to lateral loads. 7.10.6 The recommendations presented above are generally applicable to the design of rigid concrete or masonry retaining walls having a maximum height of 8 feet. In the event that walls higher than 8 feet or other types of walls are planned, such as crib-type walls, Geocon Incorporated should be consulted for additional recommendations. 7.11 Slope Maintenance 7.11.1 Slopes that are steeper than 3:1 (horizontahvertical) may, under conditions which are both difficuh to prevent and predict, be susceptible to near surface (surficial) slope instability. The instability is typically lunited to the outer three feet of a portion of the slope and usually does not directly impact the improvements on the pad areas above or below the slope. The occurrence of surficial instability is more prevalent on fill slopes and is generally preceded by a period of heavy rainfall, excessive irrigation, or the migration of Project No. 06105-12-05 - 18 - August 27,2001 subsurface seepage. The disturbance and/or loosening of the surficial soils, as might resuh from root growtii, soil expansion, or excavation for irrigation lines and slope planting, may also be a significant contributing factor to surficial mstability. It is, therefore, recom- mended that, to the maximum extent practical: (a) disturbed/loosened surficial soils be either removed or properly recompacted, (b) irrigation systems be periodically inspected and maintained to eliminate leaks and excessive irrigation, and (c) surface drains on and adjacent to slopes be periodically maintamed to preclude ponding or erosion. It should be noted that although the incorporation of the above recommendations should reduce the potential for surficial slope instability, it will not eliminate the possibility, and, therefore, it may be necessary to rebuild or repair a portion of the project's slopes in the future. 7.12 Drainage 7.12.1 Establishing proper drainage is imperative to reduce the potential for differential soil movement, erosion and subsurface seepage. Positive measures should be taken to properly finish grade the buildmg pads after structures and other improvements are in place, so that drainage water from the building pads and adjacent properties is directed to streets away from foundations and tops of slopes. Experience has shown that even with these provisions, a shallow groundwater or subsurface condition can and may develop in areas where no such condition existed prior to site development. This is particularly true where a substantial mcrease in surface water infiltration results from an increase in landscape irrigation. 7.13 Plan Review 7.13.1 The geotechnical engineer and engineering geologist should review the grading and foundation plans prior to finalization to verify their compliance with the recommendations of this report and determine the necessity for additional comments, recommendations and/or analysis. ProjectNo. 06105-12-05 - 19- August 27,2001 LIMITATIONS AND UNIFORMITY OF CONDITIONS 1. The recommendations of this report pertain only to the site investigated and are based upon the assumption that the soil conditions do not deviate from those disclosed in the investigation. If any variations or undesirable conditions are encountered during construction, or if the proposed construction will differ from that anticipated herein, Geocon Incorporated should be notified so that supplemental recommendations can be given. The evaluation or identification of the potential presence of hazardous or corrosive materials was not part of the scope of services provided by Geocon Incorporated. 2. This report is issued with tiie understanding that it is the responsibility of the owner, or of his representative, to ensure that the information and recommendations contained herein are brought to the attention of the architect and engineer for the project and mcorporated into the plans, and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations in the field. 3. The findings of this report are valid as of the present date. However, changes in the conditions of a property can occur with the passage of time, whether they be due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of three years. Project No. 06105-12-05 August 27,2001 SOURCE : 2001 THOMAS BROTHERS MAP SAN DIEGO COUNTY, CALIFORNIA REPRODUCED WITH PERMISSION GRANTED BY THOMAS BROTHERS MAPS. THIS MAP IS COPYRIGHTED BY THOMAS BROS. MAPS. IT IS UNLAWFUL TO COPY OR REPRODUCE Aa OR ANY PART THEREOF, WHETHER FOR PERSONAL USE OR RESALE, WITHOUT PERMISSION 4 M NO SCALE GEOCON O INCORPORATED GEOTECHNICAL CONSULTANTS 6960 FLANDERS DRIVE • SAN DIEGO, CALIFORNIA 92121 • 2974 PHONE 858 558-6900 - FAX 858 558-6159 VICINITY MAP GEOCON O INCORPORATED GEOTECHNICAL CONSULTANTS 6960 FLANDERS DRIVE • SAN DIEGO, CALIFORNIA 92121 • 2974 PHONE 858 558-6900 - FAX 858 558-6159 VILLAGES OF LA COSTA THE RIDGE CARLSBAD, CALIFORNIA AS/AML DSK/EOOOO DATE 08-27-2001 PROJECT NO. 06105 -12 - 05 FIGil VICINITY PROJECT NO. 06105-12-05 ASSUMED CONDITIONS: Slope Height Slope Inclination Total Unit Weight of Soil Angle of Internal Friction Apparent Cohesion No Seepage Forces ANALYSIS: H = 65 feet 2:1 (Horizontal:Vertical) Yt =130 pounds per cubic foot (j) = 32 degrees C = 300 pounds per square foot YHtan(|) c Equation (3-3), Reference 1 FS = NcfC Equation (3-2), Reference 1 YH \^ ~ 17.6 Calculated Using Eq. (3-3) Ncf = 50 Determined Using Figure 10, Reference 2 FS = 1.7 Factor of Safety Calculated Using Eq. (3-2) REFERENCES: (1) Janbu, N., Stability Analysis of Slopes with Dimensionless Parameters, Harvard Soil Mechanics, Series No. 46, 1954. (2) Janbu, N., Discussion of J. M. Bell, Dimensionless Parameters for Homogeneous Earth Slopes, Joumal of Soil Mechanics and Foundation Design, No. SM6, November 1967. FILL SLOPE STABILITY ANALYSIS VILLAGES OF LA COSTA—THE RIDGE CARLSBAD, CALIFORNIA FIGURE 6 J PROJECTNO. 06105-12-05 ASSUMED CONDITIONS: Slope Height H = Infinite Depth of Saturation Z = 3 feet Slope Inclination 2:1 (Horizontal :Vertical) Slope Angle i = 26.5 degrees Unit Weight of Water Yw = 62.4 pounds per cubic foot Total Unit Weight of Soil Yt = 130 pounds per cubic foot Angle of Intemal Friction <l> = 32 degrees Apparent Cohesion C = 300 pounds per square foot Slope saturated to vertical depth Z below slope face. Seepage forces parallel to slope face ANALYSIS: ¥S = C + (r^-rJZcos^itan</> YfZsmicosi = 5.7 REFERENCES: (1) Haefeii, R. The Stability of Slopes Acted Upon by Parallel Seepage, Proc. Second Intemational Conference, SMFE, Rotterdam, 1948, 1, 57-62. (2) Skempton, A. W., and F. A. Delory, Stability of Natural Slopes in London Clay, Proc. Fourth Mtemational Conference, SMFE, London, 1957, 2,378-81. SURFICIAL SLOPE STABILITY ANALYSIS VILLAGES OF LA COSTA—THE RIDGE CARLSBAD, CALIFORNIA FIGURE 7 APPROVED FILTER FABRIC 6" DIA. PERFORATED SUBDRAIN PIPE 1" MAX. OPEN-GRADED AGGREGATE 9 CUBIC FT./FT. MINIMUM NOTES: 1 SUBDRAIN PIPE SHOULD BE 6-INCH MINIMUM DIAMETER, PERFORATED, THICK WALLED SCHEDULE 40 PVC, SLOPED TO DRAIN AT 1 PERCENT MINIMUM AND CONNECTED TO STORM DRAIN SYSTEM OR APPROVED OUTLET 2 WHERE DRAIN EXCEEDS 500 FEET, PIPE DIAMETER SHOULD BE INCREASED TO 8 INCHES 3 FILTER FABRIC TO BE MIRAFI UON OR EQUIVALENT NO SCALE TYPICAL SUBDRAIN DETAIL GEOCON ^ INCORPORATED GEOTECHNICAL CONSULTANTS 6960 FLANDERS DRIVE • SAN DIEGO, CALIFORNIA 92121 - 2974 PHONE 858 558-6900 • FAX 858 558-6159 VILLAGES CFL A COSTA THE RIDGE CARLSBAD, CALIFORNIA AS/AML DSK/EOOOO DATE 08-27-2001 PROJECT NO. 06105-12-05 Fias SD/IXVIII/RSS Appendix A APPENDIX A FIELD INVESTIGATION The latest phase of field investigation was performed during the period of October 6 through October 14, 1999, and consisted of additional geologic mapping and excavation of 11 exploratory trenches and 16 hydraulic "air track" drill holes. The approximate locations of the trenches and borings are shown on the Geologic Maps, Figures 2 through 5. The exploratory trenches were excavated by means of a Caterpillar 350 Trackhoe, equipped with a 30-inch-wide bucket. An IngersoU-Rand 500 pneumatic percussion, 4-inch-diameter drill with hydraulic pull-down was used for the air-track holes at selected locations in order to gain additional information regarding the rippability characteristics of the underlying bedrock. During the excavations of trenches, the materials encountered were visually examined, classified, and logged. Logs ofthe exploratory trenches are presented on Figures A-1 through A-11. A graphical representation of each of the ak-track borings is presented on Figures A-12 through A-27. The graphs depict the rate (in seconds per foot) at which the drill penetrated each foot of depth examined. Project No. 06105-12-05 August 27, 2001 PROJECT NO. 06105-12-05 DEPTH IN FEET SAMPLE NO. > ID O _1 O SOIL CLASS (USCS) TRENCH T 16 ELEV. (MSL.) 620 EQUIPMENT _DATE COMPLETED CAT 350 30" BUCJOET 10/12/99 Ul Q a CJ MATERIAL DESCRIPTION 2 - - 4 - SM -t- -f-+ • + -h + + -f TOPSOIL Loose, dry, dark reddish-brown. Gravelly, Silty, medium SAND -Some clay ESCONDIDO CREEK GRANODIORITE Slighdy weathered, fractured, reddish-brown to gray, strong GRANITIC ROCK; jomt-fracmres spaced 6"-I- apart -Joints: N35E, vertical N30W, 75NE TRENCH TERMINATED AT 5 FEET REFUSAL Figure A-1, Log of Trench T 16 TORGE SAMPLE SYMBOLS ° """ ^'^""^'"^ UNSUCCESSFUL ^ ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PENETRATION TEST DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE I ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECT NO. 06105-12-05 DEPTH IN FEET SAMPLE NO. H SOIL CLASS (USCS) TRENCH T 17 ELEV. (MSL.) 540 EQUIPMENT DATE COMPLETED 10/12/99 CAT 350 30" BUCKET iUJ; 0} UJ go a CO UJ -o u - 0 MATERIAL DESCRIPTION VI- 4 - 6 - 8 - h 10 - 12 - - 14 - 16 - 18 - 20 - 22 - 24 H T17-1 T17-2 - 26 SC-CL ALLUVIUM Loose, humid, dark brown. Clayey, Gravelly fine SAND UNDIFFERENTIATED METAMORPfflC ROCK Very weathered, fractured, gray to olive, moderately strong METAMORPHIC ROCK -Numerous random to orthogonal joint-fractures -Disintegrates to a Clayey, Gravelly fme SAND Very weathered, fractured, reddish-brown, moderately strong GRANITIC ROCK -Steep to vertical dike -Disintegrates to Clayey SAND Very fractared, moderately weathered, gray to olive, strong METAMORPHIC ROCK -Excavates to Sandy GRAVEL with 4" to 6" chunks TRENCH TERMINATED AT 26 FEET Figure A-2, Log of Trench T 17 TORGE SAMPLE SYMBOLS ° ""' ^^""^'^^ UNSUCCESSFUL m ... DISTURBED OR BAG SAMPLE E. .. STANDARD PENETRATION TEST DRIVE SAMPLE (UNDISTURBED) .. CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECT NO. 06105-12-05 DEPTH IN FEET SAMPLE NO. > CD O _l O X SOIL CLASS (USCS) TRENCH T 18 ELEV. (MSL.) 550 EQUIPMENT DATE COMPLETED 10/12/99 CAT 350 30" BUCKET H jUj' mUJ ^0£ >6 a u MATERIAL DESCRIPTION - 4 - 6 - 8 - 10 Z2: •f -t- 4- •t- -t- -I- -I- -I-• + + + \- + + + + 4- • SC TOPSOIL Loose, humid, dark reddish-brown. Clayey, fine SAND with GRAVEL ESCONDIDO CREEK GRANODIORITE Very fractured, weathered, reddish-brown, strong GRANITIC ROCK -Disintegrates to Clayey SAND and excavates to 2-6" chunks TRENCH TERMINATED AT 10 FEET Figure A-3, Log of Trench T 18 TORGE D ... SAMPLING UNSUCCESSFUL SAMPLE SYMBOLS ^ ^.A^LINU uNsuuLtssruL ^ ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PENETRATION TEST DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE I ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECT NO. 06105-12-05 DEPTH IN FEET SAMPLE NO. OL >-UJ CD 1-O <E _l 3 o a X z h-H O _J Qi CD SOIL CLASS (USCS) TRENCH T19 ELEV. (MSL.) 555 EQUIPMENT DATE COMPLETED 10/12/99 CAT 350 30" BUCKET Zi.i^ H ;UJ' f cn§ zfS-J 5- Oi. a Ul Zi I-tn H LU -o u - 0 - 2 - 4 - - 6 ill MATERIAL DESCRIPTION -I- -I-+ + + + + + + + • + SM TOPSOIL Loose, dry, dark brown. Gravelly, Silty, coarse SAND ESCONDIDO CREEK GRANODIORITE Fractured, slightly weathered, light to olive, strong GRANITIC ROCK with jomt-fractures 2"-6" apart -Joints: E-W, 40S -Joint-fracmre > 10" apart TRENCH TERMINATED AT 8 FEET REFUSAL Figure A-4, Log of Trench T 19 TORGE SAMPLE SYMBOLS ° - '''''''' UNSUCCESSFUL ^ ... DISTURBED OR BAG SAMPLE E. B. .. STANDARD PENETRATION TEST DRIVE SAMPLE (UNDISTURBED) .. CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE NOTE; THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECTNO. 06105-12-05 DEPTH IN FEET SAMPLE NO. > CD O H SOIL CLASS (USCS) TRENCH T20 ELEV. (MSL.) 575 EQUIPMENT DATE COMPLETED 10/12/99 CAT 350 30" BUCKET CO' >- a uj$5 PI- CO MATERIAL DESCRIPTION - 2 - - 6 - 8 - 10 - - 12 + + -t- -)- -1- -1-+ + + + + + + + + + + + + + + + + • + + SM TOPSOIL Loose, dry, dark red-brown, Silty, medium-coarse SAND ESCONDIDO CREEK GRANODIORITE Highly fracmred, slightly weathered, light brown-olive, moderately strong GRANITIC ROCK -With orthogonal joint-fractures 1/2" to 5 ' apart -Disintegrates to a Silty, coarse SAND TRENCH TERMINATED AT 12 FEET NEAR-REFUSAL Figure A-5, Log of Trench T 20 TORGE „ . , r. o,r, ,T,^T o n ... SAMPLING UNSUCCESSFUL SAMPLE SYMBOLS „ m ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PENETRATION TEST DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECT NO. 06105-12-05 DEPTH IN FEET SAMPLE NO. >-CD O _l o X H H SOIL CLASS (USCS) TRENCH T 24 ELEV. (MSL.) 427 EQUIPMENT DATE COMPLETED 10/12/99 CAT 350 30" BUCKET cflR LU go Oi Q - 0 MATERIAL DESCRIPTION - 2 - - 4 - 6 - - 8 - - 10 - 12 14 - 16 18 - - 20 22 -f- + + -t- -I- -t- -f -I- I- + + -f • -f- -1- 4- • -I- -1- -I- h -f -I- -I- •f -f -1-+ + -I-+ -t- -f + • + -f + v + + + CL COLLUVIUM Stiff, moist, dark brown to olive, Sandy CLAY SAN MARCOS GABBRO Very fractured, reddish-brown to olive, moderately strong GRANITIC ROCK -Numerous random and preferred joint-fractures spaced 1/2 "-5" apart -Disintegrates to Gravelly, Clayey SAND -Joint spacing >5" TRENCH TERMINATED AT 22 FEET Figure A-9, Log of Trench T 24 TORGE SAMPLE SYMBOLS • ... SAMPLING UNSUCCESSFUL E.. . STANDARD PENETRATION TEST • .. . DRIVE SAMPLE (UNDISTURBED) @ ... DISTURBED OR BAG SAMPLE B.. . CHUNK SAMPLE z.. . WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECT NO. 06105-12-05 DEPTH IN FEET SAMPLE NO. > CD O _l O X I- H SOIL CLASS (USCS) TRENCH T25 ELEV. (MSL.) 660 EQUIPMENT DATE COMPLETED 10/14/99 CAT 350 30" BUCKET On • >- go a UJ5 PI- CA LU •O O MATERIAL DESCRIPTION - 2 - - 6 SM -I- + • + + + • + •f + • + + + TOPSOIL >^ Loose, dry, dark brown. Gravelly, Silty, coarse \ SAND ESCONDIDO CREEK GRANODIORITE Weathered, slightly fractured, light brown, strong GRANITIC ROCK -With joint-fractures > 12" apart, steep to vertical TRENCH TERMINATED AT 6 FEET REFUSAL Figure A-10, Log of Trench T 25 TORGE D ... SAMPLING UNSUCCESSFUL SAMPLE SYMBOLS LINO uNsuLLcssrut ^ ... DISTURBED OR BAG SAMPLE B.. B.. . STANDARD PENETRATION TEST DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. 06105-12-05 THE RIDGE 10/06/1999 ELEVATION 620 FEET 0) .0) I-a. m ,P 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 AIR TRACK BORING AT-1 Rippable R'PPable Non-Rippable Marginal to Non- GEOCON IMOORPOKATID 10 20 30 40 50 60 .70 80 90 100 110 DRILL RATE (seconds per foot) FIGURE A-12 06105-12-05 THE RIDGE 10/06/1999 ELEVATION 660 FEET a X t- CL UJ Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 AIR TRACK BORING AT-2 Rippable R'PP»ble Non-Rippable Marginal to Non- 1 10 20 30 40 50 60 70 80 DRILL RATE (seconds per foot) GEOCON INOOHPOXATID 90 100 110 FIGURE A-13 06105-12-05 THE RIDGE 10/06/1999 ELEVATION 627 FEET AIR TRACK BORING AT-3 Rippable R'PPable Non-Rippable Marginal to Non- 0.0 S 0) Q. UJ Q 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 GEOCON IM00RPORi.TIO 10 20 30 40 50 60 70 80 90 100 110 DRILL RATE (seconds per foot) FIGURE A-14 06105-12-05 THE RIDGE 10/06/1999 ELEVATION 635 FEET AIR TRACK BORING AT-4 Rippable R'PP^ble Non-Rippable Marginal to Non- 0) h- Q. LU Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 10 20 30 40 50 60 70 80 DRILL RATE (seconds per foot) GEOCON IMOORPOHATSD 90 100 110 FIGURE A-15 06105-12-05 THE RIDGE 10/06/1999 ELEVATION 680 FEET 0) X I- Q. LU Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 AIR TRACK BORING AT-5 Rippable ^iPPable Non-Rippable Marginal to Non- GEOCON IMOORPOKATID 10 20 30 40 50 60 70 80 DRILL RATE (seconds per foot) 90 100 110 FIGURE A-16 06105-12-05 THE RIDGE 10/06/1999 ELEVATION 623 FEET Marginal to Non- AIR TRACK BORING AT-6 Rippable ^'PPable Non-Rippable 0) X 1- Q. UJ Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 GEOCON INOORPORATBD 10 20 30 40 50 60 70 80 DRILL RATE (seconds per foot) 90 100 110 FIGURE A-17 06105-12-05 THE RIDGE 10/06/1999 ELEVATION 653 FEET Marginal to Non- AIR TRACK BORING AT-7 Rippable ^'PPable Non-Rippable GEOCON IMOORPOIiATBD 0) .9> X H Q. LU Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 10 20 30 40 50 60 70 80 90 100 110 DRILL RATE (seconds per foot) FIGURE A-18 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 665 FEET Marginal to Non- Rippable R'PPable Non-Rippable AIR TRACK BORING AT-8 X h- Q. UJ Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 GEOCON mOORPORATSS 10 20 30 40 50 60 70 80 90 100 110 DRILL RATE (seconds per foot) FIGURE A-19 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 690 FEET AIR TRACK BORING AT-9 Rippable ^^PP^ble Non-Rippable Marginal to Non- (U X I-Q. UJ Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 GEOCON INOORPORATBD 0 10 20 30 40. 50 60 70 80 90 100 110 DRILL RATE (seconds per foot) FIGURE A-20 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 668 FEET AIR TRACK ""Tn!"" BORING AT-10 Rippable J^PP»bIe Non-Rippable 0.0 f 0} JO X h- UJ Q 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 10 20 30 40 50 60 70 80 DRILL RATE (seconds per foot) GEOCON iiroonpoRAViD 90 100 110 FIGURE A-21 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 680 FEET 11 Is AIR TRACK BORING AT-11 Rippable ^iPPable Non-Rippable Marginal to Non- X I-Q. UJ Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 GEOCON IlfOORPORATID 0 10 20 30 40 50 60 70 80 90 100 110 DRILL RATE (seconds perfect) FIGURE A-22 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 678 FEET Marginal to Non- AIR TRACK BORING AT-12 Rippable R»PPable Non-Rippable 0) 0. LU O 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 GEOCON XirOORPORATBD 0 10 20 30 40 50 60 70 80 90 100 110 DRILL RATE (seconds per foot) FIGURE A-23 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 480 FEET AIR TRACK "^Tn!'*" BORING AT-13 Rippable ^iPPable Non-Rippable a X h- Q. UJ Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 GEOCON IHOOXPORATBD i i— 10 20 30 40 50 60 70 80 90 100 110 DRILL RATE (seconds per foot) FIGURE A-24 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 467 FEET 0) Q. UJ Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 AIR TRACK BORING AT-14 Rippable ^^'PPaWe Non-Rippable Marginal to Non- GEOCON mOORPORATBD 10 20 30 40 50 60 70 80 DRILL RATE (seconds per foot) 90 100 110 FIGURE A-25 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 470 FEET .03 CL UJ Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 AIR TRACK BORING AT-15 Rippable RiPPab'e Non-Rippable Marginal to Non- 10 20 30 40 50 60 70 80 DRILL RATE (seconds perfect) GEOCON IirOORPORATID 90 100 110 FIGURE A-26 06105-12-05 THE RIDGE 10/07/1999 ELEVATION 440 FEET JO CL m Q 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 Marginal to Non- AIR TRACK BORING AT-16 Rippable I^'PP»*»le Non-Rippable GEOCON IirOORPORATID 10 20 30 40 50 60 70 80 90 100 110 DRILL RATE (seconds per foot) FIGURE A-27 Appendix B APPENDIX B LABORATORY TESTING Laboratory tests were performed in accordance with generally accepted test methods of the American Society for Testing and Materials (ASTM) or other suggested procedures. Selected soil samples were tested for expansion potentials. The results of our laboratory tests are presented as follows in Table B-L TABLE B-1 SUMMARY OF LABORATORY EXPANSION INDEX TEST RESULTS Sample No. Moisture Content Dry Density pcf) Expansion Index Classification Sample No. Before Test (%) After Test (%) Dry Density pcf) Expansion Index Classification T17-1 9.6 25.3 111.2 61 Medium T17-2 7.0 16.1 122.9 15 Low ProjectNo. 06105-12-05 August 27, 2001 Appendix C APPENDIX C SELECTED BORING AND TRENCH LOGS AND LABORATORY TESTING FROM UPDATED GEOTECHNICAL EVALUATION RANCHEROS SUBDIVISION, CARLSBAD, CALIFORNIA, PREPARED BY NINYO & MOORE, DATED DECEMBER 30,1991 (PROJECT NO. 102219-01). FOR VILLAGES OF LA COSTA—THE RIDGE CARLSBAD, CALIFORNIA PROJECT NO. 06105-12-05 TEST PIT LOG Explanation of TosU Pit Log PROJECT NO. DATE UJ Ui a Ul Q Ui a. Z < Ul cc »- to 5 s u. o a >- tn 2 tu o >• cc a in ij in zi z o < o u. in tn < _i o DATE EXCAVATED. GROUND ELEVATION TEST PIT NO. LOGGED BY METHOD OF EXCAVATION LOCATION DESCRIPTION o c JO m SCALE Drive Tube tSensity sample Sand Cone density sample Bulk sample Seepage Ground water table TEST PIT LOG villages of La Costa Rancheros Subdivision Carlsbad/ California PROJECT NO DATE EXCAVATED 10/14/91 TEST PIT NO. GROUND ELEVATION 532'+/- MSL LOGGED BY PR METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION ALLUVIUM; Pale brown, damp, loose to medium dense, silty, very fine SAND; rootlet voids. Grades to olive brown, damp, stiff, sandy CLAY; trace of gravel. 04': Angular fragments of metavolcanic rock, up to 6 inches in maximum dimension. GRANITIC ROCK (Kqr); i Pale olive, yellow-brown, damp, decomposed GRANITE. 05.5': Moderately to slightly weathered, hard digging. Total depth: 5.5 Feet Ground water not encountered. Backfilled 10-14-91 TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 O c 3) m CD I ^3 SCALE 1" = 2' • 5 10 11 CO UJ _i Q. < UJ cc i-o s. o Q. to z UI O >-CC a CO o CO < u. o SM DATE EXCAVATED 10/14/91 TEST PIT NO. GROUND ELEVATION 540'+/- MSL LOGGED BY PR METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Pale reddish brown, loose, damp, silty fine SAND; rootlet voids. Gradational contact. GRANITIC ROCK (Kqr); Pale olive gray and brown, damp, intensely weathered GRANITE. 03': Slightly weathered, refusal. Total Depth: 3 Feet Ground water not encountered. Backfilled 10-14-91 DATE EXCAVATED 10/14/91 TEST PIT NO. GROUND ELEVATION 530'+/- MSL LOGGED BY PR METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Pale reddish-yellow-brown, damp, loose, silty fine SAND with gravel and small boulders of granitic rock. GRANITIC ROCK (Kqr): Pale olive-gray to yellow-brown, damp, decomposed GRANITE. 05.5': Refusal on slightly weathered rock. Total Depth: 5.5 Feet Ground water not encountered. Backfilled 10-14-91 TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 T) o c m tu I SCALE 1" = 2' UJ u. X H a. UJ a 10 11 to m < to N UI CC I- to O R CT o Q. CO z ul o > CC Q tn tn ZD < o u. o SM DATE EXCAVATED 10/14/91 TEST PIT NO. GROUND ELEVATION 525'+/- MSL LOGGED BY PR METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Pale reddish-yellow-brown, damp, loose, silty, fine SAND with gravel and small boulders. Gradational contact GRANITIC ROCK (Kqr); Olive gray to pale yellow-brown, damp, intensely weathered GRANITE. 03': Rock fragments to 18 inches in maximum dimension. 04': Refusal on fractured, slightly weathered rock, fractures randomly oriented. Total Depth: 4 Feet Ground water not encountered. Backfilled 10-14-91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 SCALE 1" =• 2' - 1 (0 Ul < to 1 - 7 10 11 UJ CC rj h-to o 2 G? O CL to z UJ a > cc o to o CO o SM CL DATE EXCAVATED 10/14/91 TEST PIT NO. GROUND ELEVATION 650'+/- MSL LOGGED BY PR METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL: Reddish-brown, damp, loose, silty, fine SAND. Grades to reddish-olive-brown, damp, firm to stiff, sandy CLAY with some gravel. GRANITIC ROCK(Kqr): Reddish-olive-brown, damp, decomposed GRANITE. 010': Moderately weathered, slow digging. Total Depth; 10 Feet. Ground water not encountered. Backfilled 10-14-91. DATE EXCAVATED 10/14/91 TEST PIT NO. GROUND ELEVATDN 635'+/- MSL LOGGED BY PR METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Reddish-brown, damp, loose to medium dense, sandy SILT. 01': Olive-gray in color with red staining. Gradational contact. SANTIAGO PEAK VOLCANICS (Jsp): Olive to reddish brown, moderately weathered, intensely fractured, METAVOLCANIC ROCK; fresh fractures exposing dark gray andesitic rock. 05.5': Refusal Total Depth: 5.5 Feet. Ground water not encountered. Backfilled 10-14-91. DATE EXCAVATED 10/14/91 TEST PIT NO. GROUND ELEVATION 627'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Reddish-brown, dry to damp, loose to medium dense, sandy SILT with clay; scattered roots and rootlets. Gradational contact. SANTIAGO PEAK VOLCANICS (Jsp): Olive to reddish-brown, METAVOLCANIC ROCK; fresh faces show dark gray, andesitic rock. 011': Refusal Total Depth: 11 Feet. No ground water encountered. Backfilled 10-14-91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 3} CD C 33 m 03 t cn Ul cc to O 2 SCALE 1" ° 2' O to z UJ o >-cc Q to o CO g !< o u. to to s o CH DATE EXCAVATED 10/14/91 TEST PIT NO. 8 GROUND ELEVATION 625'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL: Reddish-brown, dry to damp, soft to firm, sandy CLAY; scattered roots and rootlets. Gradational contact. GRANITIC ROCK (Kqr): Reddish-olive-brown, decomposed GRANITE; fine to medium texture, moderately hard. 05': Very hard digging. Total Depth: 5 Feet. No ground water encountered. Backfilled 10-14-91. TESTPIT LOG villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 lU QC I- to o 2 O o. to z Ul o >-cc o CO to u. o DATE EXCAVATED 10/14/91 TEST PIT NO. GROUND ELEVATION 620'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LCXATION See Geotechnical Map DESCRIPTION o e 33 m OD I to ML TOPSOIL: Reddish brown, dry to damp, loose to medium dense, sandy SILT with some clay. Gradational contact. SANTIAGO PEAK VOLCANICS (Jsp): Olive to reddish brown, hard, METAVOLCANIC ROCK; fresh faces show dark gray andesitic rock. 06': Refusal Total Depth: 6 Feet. No ground water encountered. Backfilled 10-14-91. SCALE 1" = 2' TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 to UJ _i a. < to tu cc 3 H-to o 2 o a. to z Ul o >-cc Q CO to to CO o DATE EXCAVATED 10/14/91 TEST PIT NO. 10 GROUND ELEVATION 655'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION o c 3D m SCALE 1" = 2' 10 11 ML TOPSOIL: Reddish-brown, dry to damp, loose to medium dense, sandy SILT with some clay; scattered roots and rootlets. Gradational Contact GRANITIC ROCK (Kqr); Reddish olive-brown, damp, moderately hard, decomposed GRANITE; fine to medium texture. 08': Extremely hard digging. Total Depth: 8 Feet. No ground water encountered. Backfilled 10-14-91 TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 P Ul tu LL to lU _J Q- < to cc to o 2 GT O a. to z UI cn >- QC Q to CO s o DATE EXCAVATED 10/14/91 TEST PIT NO. 11 GROUND ELEVATION 660'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION 3 O c n m "P SCALE 1" = 2' 10 11 ML TOPSOIL: Reddish brown, dry to damp, loose Lo medium dense, sandy SILT with some clay; scattered roots and rootlets. Gradational contact. GRANITIC ROCK (Kqr): Reddish olive-brown, decomposed GRANITE; dry, moderately hard, fine to medium texture. 0 1.5': Very hard digging. Total Depth: 1.5 Feet. No ground water encountered. Backfilled 10-14-91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 tu to LU —I O. < to I UJ GC H to U. O QL to z UJ Q >-CC o to tj CO -< o o ML DATE EXCAVATED 10/14/91 TEST PIT NO. 12 GROUND ELEVATION 655'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket L(XATION See Geotechnical Map DESCRIPTION TOPSOIL; Reddish brown, dry to damp, loose to medium dense, sandy SILT with trace of clay; scattered roots and rootlets. Gradational contact. SANTIAGO PEAK VOLCANICS (Jsp); Olive to reddish-brown hard METAVOLCANIC ROCK; andesitic rock. 03.5': Refusal, Total Depth: 3.5 Feet. No ground water encountered. Backfilled 10-14-91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California P UJ LU to UJ -I CL < to o LU CC Z) H CO O 2 o OL to Z LU a CO CJ CO o LL DATE FXCAVATED 10/14/91 TEST PIT NO. 13 GROUND ELEVATION 695'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL: Reddish-brown, dry to damp, loose to medium dense, sandy SILT; scattered roots and rootlets. Gradational contact. SANTIAGO PEAK VOLCANICS (Jsp): Olive to reddish brown, hard METAVOLCANIC ROCK; fresh faces show dark gray to blue gray andesitic rock. 05': Refusal. Total Depth: 5 Feet. No ground water encountered. Backfilled 10-14-91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-14-91 CO lU —I CL < to LU CC Z) ^-to O 2 O CL CO z tu o >- QC to to < o u. CO CO DATE EXCAVATED 10/14/91 TEST PIT NO. 14 GROUND ELEVATION 637'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION o c 31 m SCALE 1" = 2' 10 11 ML TOPSOIL; Reddish-brown, dry to damp, loose to medium dense, sandy SILT. Gradational contact. GRANITIC ROCK (Kqr); Reddish olive-brown, damp, moderately hard, fine to medium texture, decomposed GRANITE. 02': Very hard digging. Total Depth: 2 Feet. No ground water encountered. Backfilled 10-14-91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-15-91 P LU lU U. to LU _l CL 2 < to CQ Ui CC f- to O 2 IL o CL CO z Ul Q >-CC o to d to < o LL o DATE EXCAVATED 10/14/91 TEST PIT NO. 15 GROUND ELEVATION 690'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION c •JS m SCALE 1" = 2' 1 10 11 ML TOPSOIL: Reddish-brown, dry to damp, loose to medium dense, sandy SILT; scattered roots and rootlets. Gradational contact. SANTIAGO PEAK VOLCANICS (Jsp): Olive to reddish-bronw, hard METAVOLCANIC ROCK; fresh faces show dark gray andesitic rock. 03' Refusal. Total Depth; 3 Feet. No ground water encountered. Backfilled 10-15-91. DATE EXCAVATED 10/14/91 TEST PIT NO. 16 GROUND ELEVATION 690'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Reddish-brown, dry to damp, loose to medium dense, silty, fine SAND; scattered roots and rootlets. Gradational contact. GRANITIC ROCK (Kqr); Reddish olive-brown, damp, fine to medium texture, decomposed GRANITE. 06': Very hard digging, Total Depth; 6 Feet. No ground water encountered. Backfilled 10-16-91. o c m TEST PIT LOG villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-16-91 SCALE 1" " 2' -- 2 CO UJ < to I 10 11 LU QC to O IL o 0. to z UI a >-oc a to o to o J8 3 o ML DATE FXCAVATED 10/14/91 TEST PIT NO. 17 GROUND ELEVATION 550'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL: Reddish-brown, dry to damp, loose to medium dense, sandy SILT; with scattered roots and rootlets. Gradational contact. GRANITIC ROCK (Kqr): Reddish olive-brown, damp, fine to to medium-texture, decomposed GRANITE, 03': Very hard digging. Total Depth; 3 Feet. No ground water encountered. Backfilled 10-16-91. to CO ZD o 18 o DATE EXCAVATED 10/14/91 TEST PIT NO. 22 GROUND ELEVATION 520'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION ML TOPSOIL: Reddish-brown, dry to damp, soft to firm, fine sandy SILT with clay; scattered roots, and rootlets. Gradational contact. CH Dark olive-gray to reddish-brown, damp, very stiff, fine, sandy CLAY with scattered cobbles and gravel. SANTIAGO PEAK VOLCANICS (Jsp): Reddish-brown, damp, hard METAVOLCANIC ROCK; fresh faces show dark gray, andesitic rock. 09': Refusal. Total Depth: 9 Feet. No ground water encountered. Backfilled 10-16-91. Ul QC to O CL O OL CO z UI Q >-CC o CO ci to < o 3 o DATE EXCAVATED 10/14/91 TEST PIT NO. 23 GROUND ELEVATION 520'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION ML TOPSOIL; Reddish-brown, dry to damp, loose,.fine sandy SILT with clay. Gradational contact with intermittent pockets of sandy clay. SANTIAGO PEAK VOLCANICS (Jsp); Reddish-brown, hard METAVOLCANIC ROCK; fresh faces show dark gray, andesitic rock. 08' Refusal Total Depth: 8 Feet. No ground water encountered. Backfilled 10-16-91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-16-91 to UJ '_! (L 2 < CO UJ QC CO i CL O CL CO z UJ o >-QC O CO ti CO 5 LL 3 o DATE FXCAVATFD 10/14/91 TEST PIT NO. 26 GROUND ELEVATION 590'+/- MSL LOGGED BY MS METHOD (DF EXCAVATION 710 Backho.:^ w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION c 13 m OD SCALE 1" I 10 11 ML TOPSOIL; Reddish-brown, dry to damp, loose to medium dense, fine sandy SILT with trace of clay; scattered roots and rootlets. Gradational contact. GRANITIC ROCK (Kqr); Reddish olive-brown, damp, moderately hard, fine to medium texture, decomposed GRANITE. 04': Very hard digging. Total Depth: 4 Feet. No ground water encountered. Backfilled 10/16/91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-16-91 o c D m •P ro SCALE 1" = 2' 10 11 CO Ul _i QL 2 < CO LU CC 13 H CO CL O CL CO z LU a >- QC Q CO cj CO J8 3 o ML DATF FXCAVATED 10/14/91 TEST PIT NO. 21 GROUND ELEVATION 590'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Reddish-brown, dry to damp, loose to medium dense, fine sandy SILT; scattered roots and rootlets. Gradational contact. SANTIAGO PEAK VOLCANICS (Jsp): Reddish olive-brown, damp, hard METAVOLCANIC ROCK; fresh faces show dark gray andesitic rock. 03': Very hard digging. Total Depth: 3 Feet. No ground water encountered. Backfilled 10/16/91. TEST PIT LOG Villages of La Costa Rancheros Subdivision Carlsbad, California PROJECT NO. 102219-01 DATE 10-16-91 CO LU _J CL 2 < to Ul to o 2 O CL CO z Ul o a CO CJ to ZD < o LL 3 o DATE EXCAVATED 10/14/91 TEST PIT NO. 28 GROUND ELEVATION 555'+/- MSL LOGGED BY MS METHOD OF EXCAVATION 710 Backhoe w/24" Bucket LOCATION See Geotechnical Map DESCRIPTION ML l_ TOPSOIL; Reddish-brown, dry to damp, loose to medium dense, fine sandy SILT with trace of clay. Gradational contact. CL Reddish olive-brown, damp, stiff, sandy CLAY with scattered cobbles and gravel. GRANITIC ROCK (Kqr): Reddish olive-brown, damp, fine to medium texture, decomposed GRANITE; gabbroic. 05.5': Very hard digging. Total Depth; 5.5 Feet. No ground water encountered. Backfilled 10-16-91. villages of La Costa December 30,1991 Project No. 102219-01 APPENDIX B TEST PIT LOGS FROM 1988 TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100490-ni DATE 11/13/87 a UJ O V) Ul -J a S < to UJ DC H W o 2 u. o a to z UJ Q >• GC Q O ^tO to z> DATE EXCAVATED 11/13/87 JEST PIT NO. T-1 GROUND ELEVATION 375 LOGGED BY MI.H/CO METHOD OF EXCAVATION Ford 555A Backhoci LOCATION See Geotechnical Map DESCRIPTION 3 o c m IS I SM-SC -14 SCALE: 1" = 2' A)COLLUVIUM/TOPSOIL; Brown to slight red-brown, moist, loose, silty tc slightly clayey sands: abundant angular cobble- size rock; porous from 1 to 1.5 feet. B)WEATHERED BEDROCK; Mottled olive brown and orancje-brown, moist, med ium stiff to stiff, silty clays to sandy clays U clayey sands in-filled in angular rock fragments (metavolcanics). In-filling generally several inches, becomes less with depth. C) BEDROCK; Becomes lightly weatiiered, metavolcanic rock. In-filling is monor, very hard digging - near refusal. Total Depth 3'. No Caving. No Seepage. Backfilled 11/13/87. HATE EXCAVATED 11/13/87 TEST PIT NO. T-2 GROUND ELEVATION 445 LOGGED DY . MLM/CO METHOD OF EXCAVATION Ford S55A nackliot: LOCATION Geotechnical Map DESCRIPTION o c tn m TOPSOIL; Red-brown, moist,'medium dense, silty SAND; por- ous, roots and rootlets, fine to medium grained sands with coarse sands and angular gravel. Light brown, damp to moist, hard, clayey, fine tt coarse grained SAND; roots, cobble and gravel- size rock fragments. BEDROCK; Light brown, weathered granitics, moderately excavates to sand, cobble, and boulder fragments: iron and manganese stained. Jointing; NlO*'w,vertical. Total Depth 4•. No Groundwater. No Caving. Backfilled 11/13/87. TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE 11/13/87 4) « U. X H a UJ o a lU OC Zi H Ui o u. o a r UJ a >-cc a z O to 3 !5 o DATE EXCAVATED 11/13/87 TEST PIT NO. T-3 GROUND ELEVATION 480 LOGGED DY M,l^/CO METHOD OF EXCAVATION Ford FiSSA Backhoe LOCATION See Geotechnical Map DESCRIPTION o c fn n _ 0 _ 2 _4 SCALE: 1" - 2" 11 TOPSOIL/COLLUVIUM; Red-brown, moist, medium dense, silty fine to coarse SAND; roots and rootlets. SM Yellow-brown, damp, medium dense, silty, fine to coarse grained sand with angular gravel fragments roots and rootlets, slightly porous. @ 1.0': Becomes more dense. WEATHERED BEDROCK: Gray to orange-brown, dense, weathered granite rock, moderately excavates to silty, medium to coarse SAND; and angular gravels: few cobble and boulder fragments, iron and manganese stain- ing. . Total Depth 4.5". No Groundwater. No Caving. Backfilled 11/13/97, TEST PIT LOG HATF EXCAVATED 11/13/87 TEST PIT NO. T-4 GROUND ELEVATION 473 LOGGED OY HL,H/CO— METHOD OF EXCAVATION Ford 555A Backhoe LOCATION Geotechnical Maj) DESCRIPTION a c m CD I COLLUVIUM; Dark brown, wet, loose to mcdiimi tlcnse, clayey SAND; slightly porous, roots and rootlets, mod- erate amount of angular gravel. SC-CL Mottled orange and gray, wet, medium dense, sandj' CLAY/clayey SAND; fine to coarse sand, angular gravels ami cobbles. VERY WEATHERED BEDROCK; Orange and gray, moist to wet, dense, clayey coarse grained SANDS of Very weathered metamor phics; rock breaks into coarse sand, highly mag- anese stained. Faint jointing trends NSS'W, 73 Leas weathered with depth, hard excavating. Total Depth 3.5*. No Groundwater. No Caving. Backfilled 11/13/87. TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100490-01 DATE 11/13/87 ta u. o a w z UJ o >- DC o z o to 'H DATE EXCAVATED 11/13/87 fEST PIT NO. T-5 GROUND ELEVATION 523 LOGGED BY _C(L METHOD OF EXCAVATION Ford 555A Backhoe LOCATION Geotechnical Map DESCRIPTION o c 33 rn CD I tn SCALE: 1" = 2' _ 5 6 •- , 7 SM TOPSOIL; Brown to dark brown, moist to wet, loose to med- ium dense, silty SAND; roots and rootlets. SC Red-brown, moist, medium dense to dense, clayey SAND; roots and rootlets. VERY WEATHERED Gl^VNITIC BEDROCK; Light yellow-brown, dry, dense to very dense, silty, coarse grained SAND; rootlets to 3 feet, Weathered boulders surrounded by coarse SAND; excavates easily into coarse sand. Jointing: NGO'E, 70° N. Total Depth 6.5'. No Groundwater. No Caving. Backfilled 11/13/87. Tl o c 3] m CO I TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE 11/13/87 I SCALE: 1" = 2' -0 .1 UJ CC I-tO O s u a CO z Ul a >-oc o z o o SM-ML DATE EXCAVATED __11Z13Z87_ TEST PIT NO. T-7 GROUND ELEVATION 533 LOGGED BY CQ METHOD OF EXCAVATION Ford 555A Bar.M.oc LOCATION See Geotechnical Map DESCRIPTION COT.T.UVIUM/TOPSOIL; Dark brown, moist, loose, sandy SILT/silty SAND; abundant gravel and cobble-size fragments, roots and rootlets. WEATHERED BEDROCK; Mottled brown and white, damp, silty sand filliiv^ between rock fractures; rootlets, rock fractures into gravel and cobble-size fragments. BEDROCK: Brown, manganese stained, lightly weathered meta volcanic rock, breaks into gravel and cobble-size fragments. Hard excavating. Jointing; Ji54."£,M°.S.. Total Depth 3'. No Groundwater. No Caving. Backfilled 11/13/87. TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE 11/13/87 tn Ui -I a S << to o a >- t to z UJ a >-cc o z o p < o E to CO 3 u DATE EXCAVATED 11/13/87 TEST PIT NO. T-H GROUND ELEVATION 570 LOGGED BY . METHOD OF EXCAVATION Ford 555A Backhoe LOCATION See Geotechnical Map DESCRIPTION I c 3} m -4 SCALE: 1" = 2' COLLUVIUM/TOPSOIL; Brown, moist, medium dense, silty Cine to coarse SAND; with gravel, rootlets, slighty iJorous. Light red-brown, damp to moist, very dense, clayey SAND; with friable angular gravel and cobbles. VERY WEATHERED BEDROCK: Red-brown granitic rock; filling between frac- tures, breaks into gravel and cobble fragments with moderate excavation. BEDROCK; Gray-to-blue, very dense, granitic rock; clay filling in fractures, breaks into coarse sand and rock fragments with heavy excavating. Total Depth 3'. No Groundwater. No Caving. Backfilled 11/13/87, TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE SCALE: 1" i-0 -2 i: -4 u. O a CO z UJ a >-QC O z O P . < CO a o U. • CO => u SM DATE EXCAVATED _11Z13Z82_ TEST PIT NO. JLz5L GROUND ELEVATION 52i LOGGED BY CO- METHOD OF EXCAVATION Ford 555A Backhoe LOCATION See Geotechnical Map DESCRIPTION TOPSOIL: Brown, moist, loose to medium dense, silty SAND;j abundant gravel and cobble fragments, roots and rootlets. VERY WEATHERED BEDROCK; Light red-to-orange, very dense rock; fractures to coarse sand and gravel fragments, Sandy silt in-filled in fractures. BEDROCK; Orange-red and gray, lightly weathered, meta- morphic rpcka, fractures to sand and gravel fragments with heavy excavation. Total Depth 2.5'. No Groundwater. No Caving. Backfilled 11/13/87. TEST PIT LOG La Costa Ranch - Ranclieros Carlsbad, California PROJECT NO. 100498-01 DATE 11/13/87 to Ul _l CL s < CO UJ cc 3 H CO O s u. o a. >- H CO z Ul a >-cc a z o p . < CO S3 u DATE EXCAVATED 11/13/87 TEST PIT NO. T-10 GROUND ELEVATION 545 LOGGED BY t\hM/CO METHOD OF EXCAVATION Pord 555A Backhoe LOCATION See Geotechnical Map DESCRIPTION c 09 I SCALE: 1" SM TOPSOIL; Red-brown, loose, damp to moist, silty sands with abundant angular gravel and cobble frag- ments . BEDROCK; Moderate to light weathered metavolcanic rock; hard excavating. Becomes very.hard excavatintj; fractures to coLblt and small boulder fragments. Total Depth 3.5'. No Groundwater. No Caving. Backfilled 11/13/87. TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECTNO. 100498-01 | DATE 11/13/87 SCALE: 1" = 2' CO UJ -J a S < CO UJ cc =1 I-co o Z u. o a CO z UJ o >-oc o z o p < o or CO CO o n&TF FXCAVATED 11/13/07 TEST PIT NO. T-11 GROUND ELEVATION 500 LOGGED BY _MI.M METHOD OF EXCAVATION Ford 555 A Bac khoe LOCATION See Geotechnical Map DESCRIPTION c 7) m CD I -0 SM TOPSOIL; Red-brown, damp to moist, loose, very silty fine sands with angular gravel and cobble fragments; rootlets. WEATHERED BEDROCK; Gray-orange brown, weathered metavolcanic rock; fractures in-filled with silty sands, breaks to sand and cobble-size fragments, becomes larger witli depth, hard excavating in less weathered rock with depth. Total Depth 4'. No Groundwater. No Caving. Backfilled 11/13/87. TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE 11/21/87 •n o c 3} m ta I SCALE: Vertical: 1" a UJ o • 4 - 6 JLO to lU a < CO tu tr =» CO "o u. o CO z UJ o >-cc a z o p . MM to !^ CO 3 SM-SC T HATE EXCAVATED 11/21/87 TEST PIT NO. T-14 GROUND ELEVATION 580' LOGGED BY JJA METHOD OF EXCAVATION Cat 235 Trackhoe LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Brown, damp, loose., silty, sands with angular gravels and cobbles. ^ BEDROCK; Dark gray and. light brown weathered granitics. Jointing'N35»E 59»W; N70»W SCS, NSCE BO'E, N20"'V 76" E Becomes less weathered and jointed with depth. Very hard excavating. Refusal at 5.0 - 6.5' No Caving. • No Water. Backfilled 11/21/87 TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE 11/21/87 Ul cc ? CO o S u. o a >• H CO z Ul Q >-OC o z o Sco to ^ Ui 3 O n&TF EXCAVATED 11/21/87 TEST PIT NO. T-15 GROUND ELEVATION 645' LOGGED BY JJA METHOD OF FXC A VATION Cat 235 Trackhoe LOCATION Geotechnical Map DESCRIPTION SM-SC TOPSOIL; Dark gray-brown,'damp, loose, silty, sliglitly clayey, medium to coarse grained SAND with angu- lar gravels and cobbles. WEATHERED BEDROCK; Medium gray to tan, weathered granitics, mottled along Fracture Zone. Moderate to easy excava- ting. ______ BEDROCK; Dark gray and pink tan, fine to coarse grained lightly weathered granitics. Jointed, hard excavating. Refusal at 12'. No Caving. , No Water. Backfilled 11/21/87. TEST PIT LOG La Costa Ranch - Rancheros Carlijljad, California PROJECT NO. 100498-01 DATE 11/21/87 SCALE: Vertical; 1" = 4' 10 S. UJ cc I- co o S U. o a CO z Ui Q >• oc o z o 5co o SM-SC DATE EXCAVATED 11/21/^1 TEST PIT NO. T-IG 715 , nfif.izn nv MLM GROUND ELEVATION LOGGED DY METHOD OF EXCAVATION Cat 235 Trackhoe LOCATION See Geotechnical Map DESCRIPTION TOPSOIL: Grayrbrown, loose-, damp, silty, slightly clayey, medium and coarse grained SANDS; with angular gravel and cobble fragments composed of granitic! BEDROCK; Tan, light brown, lightly weathered granitic rock; joint spacing average 3-4 per foot with attitudes N20*'W, 70° NW, less jointing with depth Refusal at 3 - 5'. No Caving. No Water. Backfilled 11/21/87. TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE 11/21/87 SCALE: 1" = 4' u. O D. >- to z Ul a >-cc a z o p < o UL to to 3 u SM PATP PXP.AVATEn 11/21/87 TEST GROUND ELEVATION 652' PIT NO. T-17 LOGGED BY METHOD OF EXCAVATION Cat 235 Trackhoe LOCATION See Geotechnical Map DESCRIPTION TOPSOIL; Red-brown, loose', damp, silty, fine to coarse grained SAND; with sub-rounded to angular gravel up to 3 inches. BEDROCK; Red to tan, damp to moist, dense, very weathered granitic rock; breaks to sand, cobble and boul- der size fragments; fragments become larger with depth, moderate excavating. Light gray and cream, fine grained, lightly weathered granitic rock; hard excavating. Refusal at 9'. No Caving. No Water, Backfilled 11/21/87. TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California • PROJECT NO. HJ0498-01 DATE 11/21/87 « u. X H O. Ul O to Ul _J a S < tn Ul fiC K- to O s u. o a to z 111 Q >- CC o z o Sto 55 !^ to 3 < _J O HATE EXCAVATED 11/21/87 TEST PIT NO. T-18 GROUND ELEVATION 540' LOGGED BY JJA METHOD OF EXCAVATION Cat 2 35 Trackhoe LOCATION See Geotechnical Map DESCRIPTION o c JO m IB I'. SM SM SCALE! 1" = 4' @ TOPSOIL; Black, moist, loose, silty, fine, medium and coarse-grained sands, with angular fragments of granitics. ® SLOPEWASH; Dark gray, brown, moist, loose to mildly dense, silty sands; angular gravel to cobble-size frag- ments of medium to coarse grained granitic rock, easy excavating. © BEDROCK; Moderately weathered granitic rock fragments, excavated become larger with depth. Moderate excavating. Total Depth 12'. No Caving. No Water. Backfilled 11/21/87, TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE 11/21/07 « «> u. a UJ O to UJ _i a S < CO Ui cc 3 I-co o S U. u a CO z Ui a cc a z o ^tn DATE EXCAVATED 11/21/87 TEST PIT NO. T-19 GROUND ELEVATION 430' LOGGED BY METHOD OF EXCAVATION Cat 235 Trackhoe LOCATION See Geotechnical Map DESCRIPTION •n 5 3 •n fl a 01 8 JLO X2 SCALE: Vertical: 1" = 4' SM "1 TOPSOIL; Red brown-brown, moist, loose, silty, fine-med- ium grained SANDS; with abundant angular gravel and cobble fragments; roots common. BEDROCK; Red brown and gray blue, light to moderately weathered metavolcanic rock; moderate effort required for excavation, fragments to gravel size common. Excavation difficult, fractures to cobble size and larger. Refusal at 7.5'. No Caving. No Water. Backfilled 11/21/87. TEST PIT LOG La Costa Ranch - Rancheros Carlsbad, California PROJECT NO. 100498-01 DATE 11/21/87 Ui oc 3 I-CO 5 2 u. o a CO z Ul a >- DC O z o ^co o - IL CO u CO CO 3 DATE EXCAVATED 11/21/87 TEST PIT NO. T-21 GROUND ELEVATION 497' LOGGED DY METHOD OF EXCAVATION Cat 235 Trackhoe LOCATION Geotechnical Map DESCRIPTION _ 6 .10 12 .14 SCALE: Vertical: 1" = 4' SM TOPSOIL; Red brown, deunp,-loose, silty, sands with very abundant angular gravel and cobble size frag- ments of metavolcanics. BEDROCK; Blue gray to gray, pyrititic metamorphic rock, jointing set E-W 70°S @ 2 - 3 feet, other joint ing less common 0 NlO'E, 70''E; N20''W 85°W. Hard excavating. Refusal at 8.5'. No Caving. No Water. Backfilled 11/21/87. I I I Villages of La Costa December 30, 1991 Project No. 102219-01 APPENDIX C Rippability Seismic refraction traverses were conducteci on the site to evaluate the rippability of the bedrock. In general, compression wave velocities can be correlated to rock hardness. The relationship between rock rippability and seismic velocrity is empirical and assumes a homogenous rock mass. Localized areas of differing composition, texture, or structure may affect both the measured data and the actual rippability of the rock mass. The rippabUty of a rock mass is also dependent upon the excavation equipment used and the sldll and experience of the equipment operator The following rippability chart is based on our experience v^th similar materials on projects in southem Califomia. It assumes that a Caterpillar D-9 dozer ripping -with, a single shank is used. 0 to 2000 fVsec Easy Ripping' 2000 to 4000 ft/sec Moderate Ripping 4000 to 5500 a/sec Difficult Ripping, Possible Localized Blasting 5500 to 7000 ft/sec Very EXfficult Ripping, Probable Blasting Greater than 7000 fly'sec Blasting Generally Required Table C-1 lists the average velocities and depths calculated from the seismic traverses conducted during this evaluation. The seismic information collected in the 1988 evaluation has been re-formatted and is presented in Table C-2. Geologic layer profiles from the current sxorvey are also included in this appendix. Please note the vertical scale changes on the profiles. It should also be noted that as a general rule-of-thumb, the effective depth of a seismic traverse is approximately one-third of the line length. The length of the seismic lines for this survey and the 1988 survey are listed v^dth the interpretations. Villages of La Costa December 30,1991 Project No. 102219-01 TABLE C-1 Seismic Traverse Results (1991) Traverse NoTLength Velocity Feet/Second Depth in Feet FWD REV Rippabilty SLl 120 ft VI = 2,500 V2= 5,700 0-8 +8 0-5 +5 Easy to Moderate Very Difficult SL2 230 ft VI = 3,300 V2= 6,300 V3 = 10,000 0-14 14-34 +34 0-5 5-34 +34 Moderate Very Difficult Nonrippable SL3 230 ft VI = 1,900 V2 =s 5,600 V3 = 8,500 0-2 2-36 +36 0 - 7 7-25 +25 Easy Very Difficult Nonrippable SL4 230 ft VI = 1,100 V2 = 5,300 V3 = 10,100 0-2 2-47 +47 0-3 3-51 +51 Easy Difficult to Very Difficult ' Nonrippable SIS 120 ft VI = 1,100 V2 = 5,800 V3 = 10,700 0-4 4-21 +21 0-4 4-29 +29 Easy Very Difficult Nonrippable SL6 120 ft VI = 1,300 V2 = 12,000 0 - 3 +3 0-3 +3 Easy Nonrippable SL7 120 ft VI = 1,900 V2= 4,600 0-2 +2 0-4 +4 Easy Difficult SL8 120 ft VI = 1,300 V2 = 5,400 V3 = 9,500 0-2 2-20 +20 0-4 4-28 +28 East Difficult to Very Difficult Nonrippable SL9 120 ft VI = 1,100 V2 = 7,300 V3 = 14,400 0 - 3 3 - 27 +27 0-4 4-14 +14 Easy Nonrippable Nonrippable 100 ft VI = 1,300 V2 = 8,400 0-3.5 +3.5 0 - 2.5 +3.5 '•.•'Easy Nonrippable Villages of La Costa December 30, 1991 Project No. 102219-01 TABLE C-2 Seismic Traverse Results (1988) Traverse NoTLength Velocity Feet/Second Depth in Feet FWD REV Rippabilty STl 100 ft VI = 2,200 V2 = 5,200 0-3 +3 0-8 +8 Easy to Moderate Very Difficult . ST2 too ft VI = 2,500 V2 = 5,800 V3 = 15,000 0-6 6-39 +39 0-4 +4 Easy to Moderate Very Difficult Nonrippable ST3 100 ft VI = 2,300 V2 = 5,300 V3 = 15,000 0-2 +2 0-6 6-38 +38 Easy to Moderate Difficult to Very Difficult Nonrippable ST4 100 ft VI = 2,000 V2 = 5,000 V3 = 10,000 0 - 2 +8 0-7 7-27 +27 Easy to Moderate Difficult to Very Difficult Nonrippable ST5 100 ft Vi = 1,800 V2 = 4,300 V3 = 10,700 0 - 7 7-24 +24 0-5 +5 Easy Moderate Nonrippable ST6 165 ft VI = 2,900 V2 = 9,800 0-8 +8 0-6 . +6 / Easy Nonrippable ST7 165 ft VI = 2,400 V2 = 6,500 V3 = 12,500 0-3 3-5 +35 0- 5' 5 - 32 +32 Easy to Moderate Very Difficult Nonrippable ST8 165 ft VI = 2,600 V2 = 5,500 V3 = 10,000 0 - 3 3 - 17 +17 0 - 5 5 - 27 +27 Moderate Very Difficult Nonrippable ST9 100 ft VI = 4,500 V2 = 8,000 V3 = 15,000 0 - 7 7-26 +26 0-5 +5 Difficult Nonrippable Noiuippable STIO 100 ft VI = 2,500 V2 = 3,300 V3 = 5,000 0- 9 9 - 23 +23 0-2 2-15 +15 Easy to Moderate Moderate Difficult to Very Difficult ; m Geo Logic REFRACT 2.29 18 Nov 1991 Geologic model oarameters: N layers = 2 R velocity = 0 Forward files: VLC-1 Reverse files: VLC-IR GeoIogiD Lager Profile I> e P t h 3B 45 69 75 Distance fpoN Fopwai^ Shot 90 185 Geologic Model Profile for 2 Layers Fwd Shot Layer Velocity Dip Angle Depth Elev 1 2 2493 5736 0.00 1.39 8.4 -8.4 Averaging Interval 4- 118 Rev Shot Deoth Elev 4 . 5 -4.5 Geo Logic REFRACT 2.29 14 Nov 1991 Geologic model parameters: N layers = 3 R velocity = 0 Forward files: VLC-2 Reverse files: VLC-2R e P t h Geolosric Layer Fnfile SB 75 m 125 150 Distance fpon Forward Shot 175 280 225 Geologic Model Profile, for 3 Layers Fwd Shot Averaging Layer Velocity Dip Angle Depth Elev Interval Rev Shot Depth Elev 1 2 3 3269 6276 10013 -5.99 -2.96 -5.76 16.4 35. 1 -16.4 -35.1 11- 228 22- 205 4.4 34.4 -28.4 -58.4 Geo Logic REFRACT 2.29 13 Nov 1991 Geologic model parameters: N layers = 3 R velocity = 0 Forward files: VLC-3 Reverse filesi VLC-3R e P t h Geologic Laser Profile 58 75 108 125 150 Distance fron Forward Shot 175 280 225 Layer 1 2 3 Geologic Model Profile for 3 Layers Fwd Shot Velocity Dip Angle Depth Elev 1852 5563 8455 -4.74 -6.03 -1 .17 1.7 37 .0 -1.7 -37.0 Averaging Interval 1- 227 33- 215 Rev Shot Depth Elev 6 . 9 22. 3 -25.9 -41 .8 Geo Logic REFRACT 2.29 13 Nov 1991 Geologic model parameters: N layers = 3 R velocity = O Forward files: VLC-4 Reverse filesi VLC-4R Geologic Layer Profile e ? h 75 108 125 150 Distance froN Forward Shot Geologic Model Profile for 3 Layers Fwd Shot Averaging Layer Velocity Dip Angle Depth Elev Interval Rev Shot Depth Elev 1 2 3 1064 5262 10087 -1.87 -2.08 -3.06 2.0 46. 6 -2.0 -46 . 6 0- 229 27- 199 2.9 51 .4 -10.4 -58.9 Geo Logic REFRACT 2.29 13 Nov 1991 Geologic model parameters: N layers = 3 R velocity = 0 Forward files: VLC-5 Reverse files: VLC-5R n Geologic Layer Profile -20.«r7 W-////////////////7/7//////// :vN\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\Vs~^ Y77/p7777777777777777777777/y///yy/yy''/f^ ~6>F.W777/ ///////////// /.'/////////////////.'///////////////,'/ /////////trjTTi m//////7///////////// 10692 ///////7///7///////////////////////fA V7^/////A/////////////////^// 15 30 45 60 75 Distance froN Forward Shot 90 105 Geologic Model Profile for 3 Layers Layer 1 2 3 Fwd Shot Velocity Dip Angle Depth Elev 1099 5817 10692 4.54 4.05 •0.67 4.1 20. 5 -4.1 -20. 5 Averaging Interval 1- 119 9- 100 Rev Shot Depth Elev 5 . 1 31 .4 4.4 -21 .9 Geo Logic REFRACT 2.29 18 Nov 1991 Geologic model parameters: N layers = 2 R velocity = O Forward files: VLC-6 Reverse files VLC-6R 10.0 Geologic Layer Profile -20.ffi'v\'; A\\\ -25.0K^\\\\ .,.., .\\\\\ 12042 \\\\\\\\\\\\\ ,,., -30.0h^\\\\\V\A\\\\\\V\\^^^^ -40 15 30 45 60 75 Distance fron Forward Shot 90 185 Geologic Model Profile for 2 Layers Fwd Shot Averaging Layer Velocity Dip Angle Depth Elev Interval 1 2 Rev Shot Depth Elev 1316 12042 -2.39 -2.03 3.0 -3.0 0- 120 2.2 -7.2 Geo Looic REFRACT 2.29 IB Nov 1991 Geologic model parameters: N layers = 2 R velocity = 0 Forward files: VLC-7 Reverse files: VCL-7R Geologic Layer Profile D e ? h IS 30 45 6 0 75 Distance froN Forward Shot 1 2 Geologic Model Profile for 2 Layers Fwd Shot Layer Velocity Dip Angle Depth Elev 1923 4575 0.00 -1.43 1.5 -1.5 Averag ing Interval 1- 118 Rev Shot Depth Elev 4 . 5 -4.5 Geo Logic REFRACT 2.29 14 Nov 1991 Geologic model parameters: N layers = 3 R velocity = 0 Forward files: VLC-8 Reverse files: VLC-8R 4.8 Geologic Layer Profile ///;/////r//////-y//\i///yyy'////././///.'//'/,///'//////i 30 45 60 75 Distance froM Forward Shot Geologic Model Profile for 3 Layers Layer Velocity Fwd Shot Averaging Dip Angle Depth Elev Interval Rev Shot Depth Elev 1 2 3 1333 5381 9511 1.48 0.42 -4.25 1.9 18. 5 -1.9 -18.5 0- 119 10- 99 4 . 1 30 . 5 -1.0 -27.4 I Geo Logic REFRACT 2.29 13 Nov 1991 Geologic model parameters: N layers = 3 R velocity = 0 Forward files: VLC-9 Reverse files: VLC-9R Geologic Layer Profile D e ? h 15 30 45 68 75 Distance froH Forward Shot BeoloQic Made! Profile tar 3 Layers Layer 1 2 3 Fwd Shot Velocity Dip Angle Depth Elev 1111 7329 14444 -2.39 -3.01 6.45 2.9 31.7 -2.9 -31 .7 Averaging Interval 0- 119 21- 116 Rev Shot Depth Elev 4.2 13 .2 -9.2 -18.2 Geo Logic REFRACT 2.29 18 Nov 1991 Geologic model parameters: N layers = 2 R velocity = 0 Forward files: VLC-IOF Reverse files: VLC-IOF Geologic Layer Profile D e P t h 8 10 20 30 40 50 60 70 Distance froK Forward Shot 98 100 1 2 Geologic Model Profile for 2 Layers Fwd Shot Layer Velocity Dip Angle Depth Elev 1263 8415 10.37 10.34 3.5 •3.5 Averag ing Interval 1- 99 Rev Shot Depth Elev 3.6 14.4 I.* I. I i3 f i' tr r i r . •.••v.-;..-r-. • '-t^ #r'- 1 .e.-- ^VXrV'-''-! ifeV-. ••• •:• • y-^,:V:::^-:S::cffyi&^ •l;"<;••.•v'vaft«f^:^5feS^^ • , J...: . ..... . Villages of La Costa December 30, 1991 Project No. 102219-01 APPENDIX D Laboratory Testing Classification Soils were visually and texturaUy classified in the field in accordance with the Unified Soil Qassification System. Selected samples were evaluated in the laboratory for grain-size distribution in general accordance with ASTM D422-63, and for Atterberg limits testing in general accordance with ASTM D4318-84. These test results were utilized in evaluating the soil classifications in accordance with the Urufied Soil Qassification System. The soil dassifications are indicated on the logs of the exploratory excavations in Appendix B. The resxilts of the Atterberg limits testing and the grain-size distribution curves are shown on Figures D-1 through D-5. Consolidation Tests Consolidation tests were performed on selected samples remolded and compacted to 90 percent relative compaction in general accordance with ASTM D2435-80. The samples were satxirated during testing to represent adverse field conditions. The percent consolidation for each load cycle was recorded as a ratio of the amount of vertical compression to the original height of the sample. The results of the tests are summarized on Figures D-6 and-D-7. Direct Shear Tests Direct shear tests were performed on remolded samples, compacted to 90 percent relative density, in general accordance with ASTM D3080-72 to evaluate the shear strength characteristics of the proposed fill materials. The samples were inundated during shearing to represent adverse field conditions. Resvdts are shown on Figures D-8 through D-11. Expansion Index Tests The expansion potential of selected materials was evaluated in general accordance with the Expansion Index Test, U.B.C. Standard No. 29-2. Specimens were molded under a specified compactive energy at approximately 50 percent saturation (plus or minus 1 percent). The prepared 1-inch thick by 4-inch diameter specimens were loaded v\ith a surcharge of 144 Villages of La Costa December 30,1991 Project No. 102219-01 pounds per square foot and were inundated with tap water. Readings of voliametric swell were made for a period of 24 hours. The results of these tests are presented in the Table D-1. The results of the expansion index tests conducted in the 1988 investigation are also reproduced in Table D-1. Maximum Dry Densitv and Optimum Moisture Content Tests The maximum dry density and optimum moisture content of selected representative soil samples were evaluated in general accordance vnih. ASTM D1557-78. The results of the tests are summarized in Table D-2. Corrosivity Testing Corrosivity testing was conducted on two selected soil samples. The analysis was conducted ^1 by Quality Assurance Laboratory The results of their analyses is presented as Table D-3. u SYMBOL LOCATION DEPTH (FT.) 7. PASSING 200 LL (%) PL (%) PI (%) u.s.c.s.* • TP-5 1.0-2.0 52.3 41 16 25 CL O TP-8 1.5-2.0 81 56 25 31 CH • TP-16 0.0-1.0 44.8 22 20 2 SM 1 TP-21 0.5-1.5 70.5 26 22 4 ML * Enfire Sample 60 50 Q. X 40 UJ >- o I— CO 30 20 10 Y / CH o / CL » . A MH & OH A ML &• OL 10 20 30 40 50 60 70 LIQUID LIMIT (LL), % 80 PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 4318-84 ATTERBERG LIMITS TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. 102219-01 DATE 12/91 FIGURE D-1 dir*ct»h.dwg I I GRAVEL SAND FINES Coarse Fine Coarse Medium Fine Silt Clay 1 0.S 0.1 a.os CRAIN SIZE IN MiLUMCTCItS 0.01 0.005 0.OB1 0.OO0S Symbol Hole Number Depth (Feet) Liquid Umit Plostie Limit Plosticity Index Soil Type • TP-5 1.0-2.0 41 16 25 CL GRADATION TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. 102219-01 DATE 12/91 FIGURE D-2 RB»nTrTt mm GRAVEL SAND FINES Coarse Fine Coarse Medium Fine Silt Clay 100 so 80 S 70 oe u 2 90 30 20 10 0 U.S. STANDARO SCve NUMBERS 1-1/r i/e j/r « t i« M HYOROUETEII SO 100 200 10 S 0.S 0.1 o.os BRAIN SIZE IN UILUMETCRS 0.01 0.005 0.001 0.0005 Symbol Hole Number Depth (Feet) Liquid Limit Plastic Limit Plasticity Index Soil Type • TP-8 1.5-2.0 56 25 31 CH GRADATION TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CAUFORNIA PROJECT NO. 102219-01 nfftnTr^ nwn DATE 12/91 FIGURE D-3 i'i I 1:; I I I I GRA^ /EL SAND FINES Coarse Fine Coarse Medium Fine Silt Clay 100 «0 so 1 70 * oe UJ S 50 2 40 S 30 20 10 0 r 1-1/r r j/r U.S. STANDARD SKVC NUMBERS i/r 4 a i« HYDROUCTCR 30 SO 100 200 0.001 O.OO05 GRAIN SIZE IN UtOIUETERS Symbol Hole Number Depth. (Feet) Liquid Limit Plostie Limit Plasticity Index Soil Type • TP-16 0.0-1.0 22 20 2 SM GRADATION TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. 102219-01 DATE 12/91 FIGURE D-4 GRAVEL SAND FINES Coarse | Fine Coarse Medium Fine Silt 1 Clay 100 «0 so I 70 a w tr kj S 50 30 20 10 0 U.S. STANDARD SIEVE NUMBERS 1-1/r 1' 3/r s/r * » M HYDROuaER 50 100 200 10 5 0.5 o:i 0.05 CRAIN SIZE IN MILUUCrtRS 0.01 0.005 0.001 0.0O05 Symbol Hole Number Depth (Feet) Liquid Limit Plastic Limit Plosticity Index Soil Type • TP-21. 0.5-1.5 26 22 4 ML GRADATION TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. DATE 102219-01 12/91 FIGURE D-5 z S CA z < a X m CO CO lU z o z l- Ui < CO u. o H Z lU u cr u a I z S < 9 o CO z o u 0.0S STRESS IN KIPS PER SQUARE FOOT 0.5 1.0 SJO 50.0 -3.0 -2.0 -1.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 imuiniiuiiuiiM! iminnimimiiiiini iniiiiuiinMiiiiiiiii: rnniiiiiiniiiiiiiuii! luniuiiiiiiiiinuuii nuiuuiiiiuiunnni niDUBiiiiinmiinu nmiuumiiiiiiiiuiiiiuiuauminiiaii;; miiiuuiuuiiuiiiiiimiiiiir.nntninnniuniiiiii 11 n 1111M H It Mil iiiiMiiiiMiiBuiiiiuiinimiiiMniiiuiiiiiiaua; iMMijiiiiiininiimnniiiniErniminiainBiiiiiii •iniuniBiuiinnniiuiiiiiiiiiiuuiiaiiiniujiiiiii: —UHiuuHuminiinniiiiiiinmnimiiniimimiii •nmnmiimimmniiiiiiiii; imiiuiiimiiinixi •uuimmniiuiiiuiuuniBiaiiiiiinuiiiuauiii: •uniBiiiiiiniiniinitniimniiiinimiiniiimnii mnniiiiniiimimiiimmnnmnniimiiim mniiiuiiiiiuuiuiiBiffiBBmnaniiiffiairi ttT rn nil ihT IIM itTiiit' REMOLDED TO 90% RELATIVE COMPACTION Field Moisture Inundated Loading Rebound Seating Cycle Boring No. TP-6 Depth (Ft.) 2.0-3.0 Soil Type WL CONSOLIDATION TEST RESULTS VILUGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. DATE 102219-01 12/91 FIGURE D-6 STRESS IN KIPS PER SQUARE FOOT S CO z < CL X lU CO CO u z o 5c H lU < CO o H z u e & I < 9 -I o CO z o o 0.05 0.1 0.5 1.0 5.0 10.0 10.0 50.0 REMOLDED TO 90% RELATIVE COMPACTION Field Moisture Inundated Loading Rebound Seating Cycle Boring No. TP-11 Depth (Ft.) 0.5-1.5 Soil Type ML CONSOLIDATION TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. DATE 102219-01 12/91 FIGURE D-7 J 4000 u. in a. IT) V) UI Dl 3000 2000 < Ul X CO 1000 1000 2000 3000 NORMAL STRESS (PSF) 4000 REMOLDED TO 90% RELATIVE COMPACTION 5000 Description Symbol Boring Number Sample Number Depth (Feet) Cohesion (PSF) Friction Angle Soil Type Peak • TP-1 4.5-5.5 405 41» SM Yield • TP-1 4.5 - 5.5 200 4l' SM DIRECT SHEAR TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. :ATE FIGURE D-8 102219-01 12/91 FIGURE D-8 cn a. cn Ul oc I— oc < UJ X to 4000 3000 2000 1000 1000 2000 3000 NORMAL STRESS (PSF) 4000 5000 Description Symbol Boring Number Sample Number Depth (Feet) Cohesion (PSF) Friction Angle Soil Type Peak • TP-6 2.0-3.0 365 30» ML Yield • TP-6 2.0-3.0 300 26" ML REMOLDED TO 90% RELATIVE COMPACTION dir«et«h.tfwg DIRECT SHEAR TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. DATE 102219-01 12/91 FIGURE D-9 cn Q. CO cn Ul oc cn cc < UJ X tn 4000 3000 2000 1000 1000 2000 3000 NORMAL STRESS (PSF) 4000 5000 Description Symbol Boring Number Sample Number Depth (Feet) Cohesion (PSF) Friction Angle Soil Type Peak • TP-6 4.5-5.5 275 33° ML-GM Yield • TP-6 4.5-5.5 200 29° ML-GM REMOLDED TO 90% RELATIVE COMPACTION DIRECT SHEAR TEST RESULTS VILLAGES OF LA COSTA RANCHEROS SUBDIVISION CARLSBAD, CALIFORNIA PROJECT NO. DATE 102219-01 12/91 FIGURE D-10 Villages of La Costa December 30,1991 Project No. 102219-01 TABLE D-1 1991 EXPANSION INDEX TEST RESULTS Sample Location Expansion Index Expansion Potential. TP-5 @ 1.0' to 2.0' 46 Low TP-8 @ 1.5' to 2.0' 105 High TP-11 @ 0.5' to 1.5' 7 Very Low TP-16 @ 0.0' to 1.0' 7 Very Low TP-21 @ 0.5' to 1.5' 18 Very Low TP-22 @ 1.0' to 2.0' 109 Hgh 1988 EXPANSION INDEX TEST RESULTS Sample Location Expansion Index Expansion Potential T-1 @ 0.0' to 1.0' 5 Very Low T-3 (® 1.0' to 3.0' 1 Very Low T-6 @ 1.0' to 1.5' 14 Very Low m Villages of La Costa December 30, 1991 Project No. 102219-01 TABLE D-2 MAXIMUM DENSITY/OPTIMUM MOISTURE CONTENT TEST RESULTS Sample Location liiiiHilsiifilM^ Description j,::}:;Maad^^ Density Optimum Moisture TP-1 @ 4.5' Gray brown silty SAND with gravel* 128.1 10.1 TP-5 @ 9.0' Reddish brovm silty GRAVEL* 120.2 13.9 TP-6@2.0' Olive gray sandy SILT 111.8 16.5 TP-6 @ 4.5' Orange-brovm silty SAND vdth gravel* 115.2 13.8 TP-11 @ 0.5' Reddish brovm sandy SILT 113.5 15.0 * Excavated bedrock IV Appendix D APPENDIX D RECOMMENDED GRADING SPECIFICATIONS FOR VILLAGES OF LA COSTA—THE OAKS CARLSBAD, CALIFORNIA , PROJECT NO. 06105-12-05 ) RECOMMENDED GRADING SPECIFICATIONS 1. GENERAL l.L These Recommended Grading Specifications shall be used in conjunction with the Geotechnical Report for the project prepared by Geocon Incorporated. The recom- mendations contained in the text of the Geotechnical Report are a part ofthe earthwork and grading specifications and shall supersede the provisions contained hereinafter in the case of conflict. 1.2. Prior to the connmencement of grading, a geotechnical consultant (Consultant) shall be employed for the' purpose of observing earthwork procedures and testing the fills for substantial conformance with the recommendations of the Geotechnical Report and these specifications. It will be necessary that the Consultant provide adequate testing and observation services so that he may determine that, in his opinion, the work was performed in substantial conformance with these specifications. It shall be the responsibility of the Contractor to assist the Consultant and keep him apprised of work schedules and changes so that personnel may be scheduled accordingly. 1.3. It shall be the sole responsibility of the Contractor to provide adequate equipment and methods to accomplish the work in accordance with appUcable grading codes or agency ordinances, these specifications and the approved grading plans. If, in the opinion of the Consultant, unsatisfactory conditions such as questionable soil materials, poor moisture condition, inadequate compaction, adverse weather, and so forth, result in a quality of work not in conformance with these specifications, the Consultant will be empowered to reject the work and recommend to the Owner that construction be stopped until the unacceptable conditions are corrected. 2. DEFINITIONS 2.1. Owner shall refer to the owner of the property or the entity on whose behalf the grading work is being performed and who has contracted with the Contractor to have grading performed. 2.2. Contractor shall refer to the Contractor performing the site grading work. 2.3. Civil Engineer or Engineer of Work shall refer to the Califomia licensed Civil Engineer or consulting firm responsible for preparation of the grading plans, surveying and verifying as-graded topography. 01 rev. 8/98 2.4. Consultant shall refer to the soil engineering and engineering geology consulting firm retained to provide geotechnical services for tiie project. 2.5. Soil Engineer shall refer to a Califomia licensed Civil Engineer retained by the Owner, who is experienced in the practice of geotechnical engineering. The Soil Engineer shall be responsible for having qualified representatives on-site to observe and test the Contractor's work for conformance with these specifications. 2.6. Engineering Geologist shall refer to a Cahfornia Hcensed Engineering Geologist retained by the Owner to provide geologic observations and recommendations during the site grading. 2.7. Geotechnical Report shall refer to a soil report (including all addenda) which may include a geologic reconnaissance or geologic investigation tiiat was prepared specifically for the development of the project for which these Recommended Grading Specifications are intended to apply. 3. MATERIALS 3.1. Materials for compacted fill shall consist of any soil excavated from the cut areas or imported to the site that, in the opinion of the Consultant, is suitable for use in construction of fills. In general, fill materials can be classified as soil fills, soil-rock fills or rock fills, as defined below. 3.1.1. Soil fills are defined as fills containing no rocks or hard lumps greater than 12 inches in maximum dimension and containing at least 40 percent by weight of material smaller than 3/4 inch in size. 3.1.2. Soil-rock fills are defined as fills containing no rocks or hard lumps larger than 4 feet in maximum dimension and containing a sufficient matrix of soil fill to allow for proper compaction of soil fill around the rock fragments or hard lumps as specified in Paragraph 6.2. Oversize rock is defined as material greater than 12 inches. 3.1.3. Rock fills are defined as fills containing no rocks or hard lumps larger than 3 feet in maximum dimension and containing httle or no fmes. Fines are defined as material smaller than 3/4 inch in maximum dimension. The quantity of fines shall be less than approximately 20 percent ofthe rock fill quantity. Gl rev. 8/98 3.2. Material of a perishable, spongy, or otherwise unsuitable nature as determined by the Consultant shall not be used in fills. 3.3. Materials used for fill, either imported or on-site, shall not contain hazardous materials as defined by tiie Cahfornia Code of Regulations, Titie 22, Division 4, Chapter 30, Articles 9 and 10; 40CFR; and any other applicable local, state or federal laws. The Consultant shall not be responsible for the identification or analysis of the potential presence of hazardous materials. However, if observations, odors or soil discoloration cause Consultant to suspect the presence of hazardous materials, the Consultant may request from the Owner the termination of grading operations within tine affected area. Prior to resuming grading operations, the Owner shall provide a written report to the Consultant indicating that the suspected materials are not hazairdous as defined by applicable laws and regulations. 3.4. The outer 15 feet of soil-rock fill slopes, measured horizontally, should be composed of properly compacted soil fill materials approved by the Consultant. Rock fill may extend to the slope face, provided that the slope is not steeper than 2:1 (horizontahvertical) and a soil layer no thicker than 12 inches is track-walked onto the face for landscaping purposes. This procedure may be utilized, provided it is acceptable to the goveming agency. Owner and Consultant. 3.5. Representative samples of soil materials to be used for fill shall be tested in the laboratory by the Consultant to determine the maximum density, optimum moisture content, and, where appropriate, shear strength, expansion, and gradation characteristics of the soil. 3.6. During-grading, soil or groundwater conditions other than those identified in tiie Geotechnical Report may be encountered by the Contractor. The Consultant shall be notified immediately to evaluate the significance ofthe unanticipated condition 4. CLEARING AND PREPARING AREAS TO BE FILLED 4.1. Areas to be excavated and filled shall be cleared and grubbed. Clearing shall consist of complete removal above the ground surface of trees, stumps, brush, vegetation, man-made structures and similar debris. Grubbing shall consist of removal of stumps, roots, buried logs and other unsuitable material and shall be performed in areas to be graded. Roots and other projections exceeding 1-1/2 inches in diameter shall be removed to a depth of 3 feet below the surface of the ground. Borrow areas shall be grubbed to the extent necessary to . provide suitable fill materials. Gl rev. 8/98 4.2. Any asphalt pavement material removed during clearing operations should be properly disposed at an approved off-site facility. Concrete fragments which are free of reinforcing steel may be placed in fills, provided they are placed in accordance with Section 6.2 or 6.3 of this document. 4.3. After clearing and grubbmg of organic matter or other unsuitable material, loose or porous soils shall be removed to the depth recommended in the Geotechnical Report. The depth of removal and compaction shall be observed and approved by a representative of the Consultant. The exposed surface shall then be plowed or scarified to a minimum depth of 6 inches and until the surface is free from uneven features that would tend to prevent uniform compaction by the equipment to be used. 4.4. "Where the slope ratio of tiie original ground is steeper than 6:1 (horizontahvertical), or where recommended by the Consultant, the original ground should be benched in accordance with the following illustration. TYPICAL BENCHING DETAIL Finish Grade Remove All Unsuitable Material As Recommended By Soil Engineer Original Ground Finish Slope Surface Slope To Be Such That Sloughing Or Sliding Does Not Occur See Note 1 See Note 2" No Scale DETAIL NOTES: (1) Key width "B" should be a minimum of 10 feet wide, or sufficiently wide to permit complete coverage with the compaction equipment used. The base ofthe key should be graded horizontal, or inclined slightly into the natural slope. (2) The outside of the bottom key should be below the topsoil or unsuitable surficial material and at least 2 feet into dense formational material. Where hard rock is exposed in the bottom of the key, the depth and configuration of the key may be modified as approved by the Consultant. Gl rev. 8/98 4.5. After areas to receive fill have been cleared, plowed or scarified, the surface should be disced or bladed by the Contractor until it is uniform and free from large clods. The area should then be moisture conditioned to achieve the proper moisture content, and compacted as recommended in Section 6.0 of these specifications. 5. COMPACTION EQUIPMENT 5.1. Compaction of soil or soil-rock fill shall be accomplished by sheepsfoot or segmented-steel wheeled rollers, vibratory rollers, multiple-wheel pneumatic-tired rollers, or other types of acceptable compaction equipment. Equipment shall be of such a design that it will be capable of compactmg the soil or soil-rock fill to the specified relative compaction at the specified moisture content. 5.2. Compaction of rock fills shall be performed in accordance with Section 6.3. 6. PLACING, SPREADING AND COMPACTION OF FILL MATERIAL 6.1. Soil fill, as defined in Paragraph 3.1.1, shall be placed by the Conti-actor in accordance with the following recommendations: 6.1.1. Soil fill shall be placed by the Contractor in layers that, when compacted, should generally not exceed 8 inches. Each layer shall be spread evenly and shall be thoroughly mixed during spreading to obtain uniformity of material and moisture in each layer. The entire fill shall be constructed as a unit in nearly level hfts. Rock materials greater than 12 inches in maximum dimension shall be placed in accordance with Section 6.2 or 6.3 of these specifications. 6.1.2. In general, the soil fill shall be compacted at a moisture content at or above the optimum moisture content as determined by ASTM D1557-91. 6.1.3. When the moisture content of soil fill is below that specified by the Consultant, water shall be added by the Contractor until the moisture content is in the range specified. 6.1.4. When the moisture content of tiie soil fill is above the range specified by the Consultant or too wet to achieve proper compaction, the soil fill shall be aerated by the Contractor by blading/mixing, or other satisfactory methods until the moisture content is within the range specified. Gl rev. 8/98 6.1.5. After each layer has been placed, mixed, and spread evenly, it shall be tiioroughly compacted by the Contractor to a relative compaction of at least 90 percent. Relative compaction is defined as the ratio (expressed in percent) of the in-place dry density of tiie compacted fill to tiie maximum laboratory dry density as detennined in accordance with ASTM D1557-9L Compaction shall be continuous over the entire area, and compaction equipment shall make sufficient passes so that the specified minimum relative compaction has been achieved throughout the entire fill. 6.1.6. Soils having an Expansion Index of greater than 5 0 may be used in fills if placed at least 3 feet below finish pad grade and should be compacted at a moisture content generally 2 to 4 percent greater than the optimum moisture content for the material. 6.1.7. Properly compacted soil fill shall extend to the design surface of fill slopes. To achieve proper compaction, it is recommended that fill slopes be over-built by at least 3 feet and tiien cut to the design grade. This procedure is considered preferable to track-walking of slopes, as described in the following paragraph. 6.1.8. As an altemative to over-building of slopes, slope faces may be back-rolled with a heavy-duty loaded sheepsfoot or vibratory roller at maximum 4-foot fill height intervals. Upon completion, slopes should then be frack-walked with a D-8 dozer or similar equipment, such tiiat a dozer frack covers all slope surfaces at least twice. 6.2. Soil-zock fill, as defined in Paragraph 3.1.2, shall be placed by the Contractor m accordance with the following recommendations: 6.2.1. Rocks larger than 12 inches but less than 4 feet m maximum dimension may be incorporated into the compacted soil fill, but shall be limited to the area measured 15 feet minimum horizontally from the slope face and 5 feet below fmish grade or 3 feet below the deepest utility, whichever is deeper. 6.2.2. Rocks or rock fragments up to 4 feet in maximum dimension may either be individually placed or placed in windrows. Under certain conditions, rocks or rock fragments up to 10 feet in maximum dimension may be placed using similar methods. The acceptability of placing rock materials greater than 4 feet in maximum dimension shall be evaluated during grading as specific cases arise and shall be approved by the Consultant prior to placement. Gl rev. 8/98 6.2.3. For individual placement, sufficient space shall be provided between rocks to allow for passage of compaction equipment. 6.2.4. For windrow placement, the rocks should be placed in trenches excavated in properly compacted soil fill. Trenches should be approximately 5 feet wide and 4 feet deep in maximum dimension. The voids around and beneath rocks should be filled with approved granular soil having a Sand Equivalent of 30 or greater and should be compacted by flooding. Windrows may also be placed utilizing an "open-face" method in lieu of the trench procedure, however, this method should first be approved by the Consultant. 6.2.5. Windrows should generally be parallel to each other and may be placed eitiier parallel to or perpendicular to the face of the slope depending on the site geometry. The minimum horizontal spacing for windrows shall be 12 feet center-to-center with a 5-foot stagger or offset from lower courses to next overlying course. The minimum vertical spacing between windrow courses shall be 2 feet from the top of a lower windrow to the bottom of the next higher windrow. 6.2.6. All rock placement, fill placement and flooding of approved granular soil in the windrows must be continuously observed by the Consultant or his representative. 6.3. Rock fills, as defined in Section 3.1.3., shall be placed by the Contractor in accordance with tiie following recommendations: 6.3.1. The base of the rock fill shall be placed on a sloping surface (minimum slope of 2 percent, maximum slope of 5 percent). The surface shall slope toward suitable subdrainage outlet facilities. The rock fills shall be provided with subdrains during construction so that a hydrostatic pressure buildup does not develop. The subdrains shall be permanently connected to controlled drainage facilities to control post-constmction infiltration of water. 6.3.2. Rock fills shall be placed in lifts not exceeding 3 feet. Placement shall be by rock trucks traversing previously placed lifts and dumping at the edge of the cunently placed lift. Spreading of the rock fill shall be by dozer to facilitate seating of the rock. The rock fill shall be watered heavily during placement. Watering shall consist of water trucks traversing in front of the cunent rock lift face and spraying water continuously during rock placement. Compaction equipment with compactive energy comparable to or greater than that of a 20-ton steel vibratory roller or other compaction equipment providing suitable energy to achieve the Gl rev. 8/98 required compaction or deflection as recommended in Paragraph 6.3.3 shall be utilized. The number of passes to be made will be determined as described in Paragraph 6.3.3. Once a rock fill hft has been covered with soil fill, no additional rock fill lifts will be permitted over the soil fill. 6.3.3. Plate bearing tests, in accordance with ASTM Dl 196-64, may be performed in both the compacted soil fill and in the rock fill to aid in determining the number of passes of tiie compaction equipment to be performed. If performed, a minimum of three plate bearing tests shall be performed in the properly compacted soil fill (minimum relative compaction of 90 percent). Plate bearing tests shall then be performed on areas of rock fill having two passes, four passes and six passes of the compaction equipment, respectively. The number of passes required for the rock fill shall be determined by comparing the results of the plate bearing tests for the soil fill and the rock fill and by evaluating the deflection variation with number of passes. The required number of passes of the compaction equipment will be performed as necessary until the plate bearing deflections are equal to or less than that determined for tiie properly compacted soil fill. In no case will the required number of passes be less than two. 6.3.4. A representative of the Consultant shall be present during rock fill operations to verify that the minimum number of "passes" have been obtained, that water is being properly appUed and that specified procedures are being followed. The actual number of plate bearing tests will be determined by the Consultant during grading. In general, at least one test should be performed for each approximately 5,000 to 10,000 cubic yards of rocArfill placed." 6.3.5. Test pits shall be excavated by the Contractor so that the Consuhant can state that, in his opinion, sufficient water is present and that voids between large rocks are properly filled with smaller rock material. In-place density testing will not be required in the rock fills. 6.3.6. To reduce tiie potential for "piping" of fines into the rock fill from overlying soil fill material, a 2-foot layer of graded filter material shall be placed above the uppermost lift of rock fill. The need to place graded filter material below the rock should be detennined by the Consultant prior to commencing grading. The • gradation of the graded filter material will be determined at the time tiie rock fill is bemg excavated. Materials typical of the rock fill should be submitted to the Consuhant in a timely manner, to allow design of the graded filter prior to tiie commencement of rock fill placement. Gl rev. 8/98 6.3.7. All rock fill placement shall be continuously observed during placement by representatives of the Consultant. 7. OBSERVATION AND TESTING 7.1. The Consultant shall be the Owners representative to observe and perform tests during clearing, grubbing, filling and compaction operations. Li general, no more than 2 feet in vertical elevation of soil or soil-rock fill shall be placed without at least one field density test being performed witiiin tiiat interval. In addition, a minimum of one field density test shall be performed for every 2,000 cubic yards of soil or soil-rock fill placed and compacted. 7.2. The Consultant shall perform random field density tests of tiie compacted soil or soil-rock fill to provide a basis for expressing an opinion as to whether tiie fill material is compacted as specified. Density tests shall be performed in tiie compacted materials below any disturbed surface. When these tests indicate tiiat the density of any layer of fill or portion thereof is below tiiat specified, the particular layer or areas represented by the test shall be reworked until tiie specified density has been achieved. 7.3. During placement of rock fill, tiie Consultant shall verify that the minimum number of passes have been obtained per the criteria discussed in Section 6.3.3. The Consultant shall request tiie excavation of observation pits and may perform plate bearing tests on the placed rock fills. The observation pits will be excavated to provide a basis for expressing an opinion as to whether tiie rock fill is properly seated and sufficient moisture has been _ applied to the material. If performed, plate bearing tests will be performed randomly on tiie surface of tiie most-recently placed lift. Plate bearing tests will be performed to provide a basis for expressing an opinion as to whether the rock ftil is adequately seated. The maximum deflection in the rock fill detennined m Section 6.3.3. shall be less than the maximum deflection of tiie properly compacted soil fill. When any of the above criteria indicate that a layer of rock fill or any portion thereof is below tiiat specified, the affected layer or area shall be reworked until the rock fill has been adequately seated and sufficient moisture applied. 7.4. A setiilement monitoring program designed by the Consultant may be conducted in areas of rock fill placement. The specific design-of the monitoring program shall be as recommended in the Conclusions and Recommendations section of the project Geotechnical Report or in the final report of testing and observation services performed during grading. Gl rev. 8/98 7.5. The Consultant shall observe the placement of subdrains, to verify that the drainage devices have been placed and constructed in substantial conformance with project specifications. 7.6. Testing procedures shall conform to tiie following Standards as appropriate: 7.6.1. Soil and Soil-Rock Fills: 7.6.1.1. Field Density Test, ASTM D1556-82, Density of Soil In-Place By the Sand-Cone Method. 7.6.1.2. Field Density Test, Nuclear Metiiod, ASTM D2922-81, Density of Soil and Soil-Aggregate In-Place by Nuclear Methods (Shallow Depth). 7.6.1.3. Laboratory Compaction Test, ASTM D1557-91, Moisture-Density Relations of Soils and Soil-Aggregate Mixtures Using 10-Pound Hammer and 18-Inch Drop. 7.6.1.4. Expansion Index Test, Uniform Building Code Standard 29-2, Expansion Index Test. 7.6.2. Rock Fills 7.6.2.1. Field Plate Bearing Test, ASTM Dl 196-64 (Reapproved 1977) Standard Method for Nonrepresentative Static Plate Load Tests of Soils and Flexible Pavement Components, For Use in Evaluation and Design of Airport and Highway Pavements. 8. PROTECTION OF WORK 8.1. During construction, tiie Contractor shall properly grade all excavated surfaces to provide positive drainage and prevent ponding of water. Drainage of surface water shall be confrolled to avoid damage to adjoining properties or to finished work on the site. The Confractor shall take remedial measures to prevent erosion of freshly graded areas until such time as permanent drainage and erosion control featires have been installed. Areas subjected to erosion or sedimentation shall be properly prepared in accordance with the Specifications prior to placing additional fill or structures. 8.2. After completion of grading as observed and tested by the Consultant, no further excavation or filling shall be conducted except in conjunction witii the services of the Consultant. Gl rev. 8/98 9. CERTIFICATIONS AND FINAL REPORTS 9.1. Upon completion of the work, Confractor shall fumish Owner a certification by the Civil Engineer stating tiiat the lots and/or building pads are graded to within 0.1 foot vertically of elevations shown on the grading plan and that all tops and toes of slopes are within 0.5 foot horizontally of the positions shown on the grading plans. After installation of a section of subdrain, the project Civil Engineer should survey its location and prepare an as-built plan of the subdrain location.- The project Civil Engineer should verify the proper outiet for tiie subdrains and the Confractor should ensure that the drain system is free of obstmctions, 9.2. The Owner is responsible for furnishing a final as-graded soil and geologic report satisfactory to the appropriate govermng or accepting agencies. The as-graded report should be prepared and signed by a California Hcensed Civil Engineer experienced in geotechnical engineering and by a Califomia Certified Engineering Geologist, indicating that the geotechnical aspects of the grading were performed in substantial conformance with the Specifications or approved changes to the Specifications. Gl rev. 8/98